Abstract: An extended area of northern Italy had experienced several West Nile virus (WNV) outbreaks during last years and the emergence of Usutu virus (USUV). Our aim is to study some factors that could explained disease patterns in the Trentino region, where circulation was detected in human sera and sentinel chickens, but no human or equine cases were reported. We collected Culex mosquito species (Diptera: Culicidae) in peridomestic environments. The specimens collected were analised for: a) its feeding behaviour b) the influence of temperature and rainfall on the abundance of mosquitoes c) the occurrence of flaviruses. Analysis of blood meals showed that Culex pipiens fed mainly on Blackbirds (Turdus merula) and House Sparrows (Passer domesticus), while Culex hortensis fed strictly on lizards. The abundance of Cx. pipiens females correlated positively with mean temperatures and negatively with rainfall (one to four weeks before capture). This negative relationship could be due to direct effect of flushing of habitats together with an indirect effect of oviposition repellency. The mean weekly temperature influenced the abundance of Cx. hortensis. No flavivirus were detected in the analysed Culex mosquitoes. These data suggest a silent cycle at low enzootic transmission levels in the area. Furthermore, we presented the first contribution to understanding the transmission role of Cx. pipiens mosquitoes in Italy, by identifying vertebrate hosts to species level.
Abstract: Surveillance, research and control of mosquito-borne diseases such as West Nile virus require efficient methods for sampling mosquitoes. We compared the efficacy of BG-Sentinel and CDC-CO2 traps in terms of the abundances of host-seeking and blood-fed female mosquitoes, and the origin of mosquito bloodmeals. Our results indicate that BGS traps that use CO2 and attractants are as effective as CDC-CO2 traps for Culex mosquito species, Oc. caspius and are also highly efficient at capturing Anopheles atroparvus host-seeking and blood-fed females with or without CO2. The CDC-CO2 trap is the least efficient method for capturing blood-fed females. BGS traps with attractants and CO2 were significantly better at capturing mosquitoes that had fed on mammals than the unbaited BGS traps and the CDC-CO2 traps in the cases of An. atroparvus and Cx. theileri. These results may help researchers to optimize trapping methods by obtaining greater sample sizes and saving time and money.
Abstract: The feeding patterns of haematophagous arthropods are of major importance in the amplification and transmission of infectious disease agents to vertebrate hosts, including humans. The establishment of new vector populations in nonnative range might alter transmission networks. The Asian tiger mosquito Aedes albopictus (Skuse) represents an example of how an invasive species can alter the risk of viral transmission to humans. Blood meal molecular identiÞcation from two sympatric mosquito species (the invasive Ae. albopictus and the native Culex pipiens) was carried out by polymerase chain reaction-based methods. Samples were collected in Barcelona metropolitan area, Spain, from June to October 2009 as part of a monitoring-control program. Blood meals were identified to the species level in 30 Ae. albopictus and 43 Cx. pipiens. Ae. albopictus acquired blood exclusively from human hosts (100%), whereas Cx. pipiens fed on a diversity of avian and mammalian hosts, including 35.7% of blood meals from humans. Based on mosquito diet, our results suggest that the Ae. albopictus invasion in Spain might increase the risk of virus transmission to humans and could support local outbreaks of imported tropical viruses such as dengue and chikungunya. However, in the studied
area, the presence of this invasive species would have a negligible effect on the transmission of zoonotic agents such as West Nile virus. However, Cx. pipiens could amplify and transmit West Nile
virus, but avian contribution to its diet was lower than that reported in North America. Feeding patterns of these mosquito species may help to understand the flavivirus outbreaks recently reported in southwestern Europe.
Abstract: Inland wetlands are worldwide distributed and have been heavily impacted in recent decades by human activities such as commerce, recreation, and food sources. The direct consequences of these activities on aquatic systems are changes in hydrology and salinity alterations, and the introduction of exotic species. Recent large-scale ecological and genetic studies across several countries and continents indicate that population structure, regional endemism, and geographic speciation patterns are common in passively dispersed aquatic invertebrates contradicting previous predictions of homogeneous genetic distribution. This essay discusses the main processes that shape these patterns and determine the biodiversity and geographic distribution of diapausing aquatic invertebrates in inland wetlands. Large-scale geographical studies to describe general patterns and to understand genetic and ecological processes determining the biogeography of cosmopolitan species are needed. Further knowledge of these issues should provide invaluable information allowing development of appropriate conservation management policies for inland waters across entire ecosystems, landscapes, and geographic regions.
Abstract: The genus Artemia comprises passively dispersed anostracan species with a distribution all around the world, except in Antarctica. We used both published and personal data to assess and update existing knowledge on the diversity and distribution of Artemia, in particular compiling also genetic and geographic information. Our results indicate there are three Artemia complexes, A. franciscana, A. tibetiana and A. salina, suggesting at least three undescribed, and one unidentified to date, highly isolated lineages, to be re-evaluated taxonomically. Additionally, at a global scale, our data set shows two large, poorly explored geographic regions in Central East Asia, which in future studies could provide interesting information on geographic speciation, the origin of parthenogenesis, and range expansion in this group. We also discuss the implications for conservation as derived from knowledge on the biodiversity (native and invasive species) and geographic distribution (i.e., identification of species/lineages, and regions occupied), which have major relevance for conservation management at the level of wetland ecosystems.
Abstract: Background:
Understanding the evolutionary origin and the phylogeographic patterns of asexual taxa can shed light on the origin and maintenance of sexual reproduction. We assessed the geographic origin, genetic diversity, and phylogeographic history of obligate parthenogen diploid Artemia parthenogenetica populations, a widespread halophilic crustacean.
Methodology/Principal Findings:
We analysed a partial sequence of the Cytochrome c Oxidase Subunit I mitochondrial gene from an extensive set of localities (including Eurasia, Africa, and Australia), and examined their phylogeographic patterns and the phylogenetic relationships of diploid A. parthenogenetica and its closest sexual relatives. Populations displayed an extremely low level of mitochondrial genetic diversity, with one widespread haplotype shared by over 79% of individuals analysed. Phylogenetic and phylogeographic analyses indicated a multiple and recent evolutionary origin of diploid A. parthenogenetica, and strongly suggested that the geographic origin of parthenogenesis in Artemia was in Central Asia. Our results indicate that the maternal sexual ancestors of diploid A. parthenogenetica were an undescribed species from Kazakhstan and A. urmiana.
Conclusions/Significance:
We found evidence for multiple origin of parthenogenesis in Central Asia. Our results indicated that, shortly after its origin, diploid A. parthenogenetica populations underwent a rapid range expansion from Central Asia towards the Mediterranean region, and probably to the rest of its current geographic distribution. This contrasts with the restricted geographic distribution, strong genetic structure, and regional endemism of sexual Artemia lineages and other passively dispersed sexual continental aquatic invertebrates. We hypothesize that diploid parthenogens might have reached their current distribution in historical times, with a range expansion possibly facilitated by an increased availability of suitable habitat provided by anthropogenic activities, such as the spread of solar saltworks, aided by their natural dispersal vectors (i.e. waterbirds).
Abstract: Emerging infectious diseases represent a challenge for global economies and public health. About one fourth of the last
pandemics have been originated by the spread of vector-borne pathogens. In this sense, the advent of modern molecular
techniques has enhanced our capabilities to understand vector-host interactions and disease ecology. However, host
identification protocols have poorly profited of international DNA barcoding initiatives and/or have focused exclusively on a
limited array of vector species. Therefore, ascertaining the potential afforded by DNA barcoding tools in other vector-host
systems of human and veterinary importance would represent a major advance in tracking pathogen life cycles and hosts.
Here, we show the applicability of a novel and efficient molecular method for the identification of the vertebrate host’s DNA
contained in the midgut of blood-feeding arthropods. To this end, we designed a eukaryote-universal forward primer and a
vertebrate-specific reverse primer to selectively amplify 758 base pairs (bp) of the vertebrate mitochondrial Cytochrome c
Oxidase Subunit I (COI) gene. Our method was validated using both extensive sequence surveys from the public domain
and Polymerase Chain Reaction (PCR) experiments carried out over specimens from different Classes of vertebrates
(Mammalia, Aves, Reptilia and Amphibia) and invertebrate ectoparasites (Arachnida and Insecta). The analysis of mosquito,
culicoid, phlebotomie, sucking bugs, and tick bloodmeals revealed up to 40 vertebrate hosts, including 23 avian, 16
mammalian and one reptilian species. Importantly, the inspection and analysis of direct sequencing electropherograms also
assisted the resolving of mixed bloodmeals. We therefore provide a universal and high-throughput diagnostic tool for the
study of the ecology of haematophagous invertebrates in relation to their vertebrate hosts. Such information is crucial to
support the efficient management of initiatives aimed at reducing epidemiologic risks of arthropod vector-borne
pathogens, a priority for public health.
Abstract: The brine shrimp Artemia is a complex genus containing sexual species and parthenogenetic lineages. Artemia franciscana is native to America and its cysts (diapausing eggs) are used worldwide as a food source in aquaculture. As a consequence, this anostracan has become an invasive species in many hypersaline aquatic ecosystems of other continents. Parthenogenetic Artemia lineages occur only in the Old World. Ten and five microsatellite markers were developed to characterize two populations for A. franciscana and two populations for diploid parthenogenetic Artemia, respectively. For A. franciscana the number of alleles ranged from 11 to 58 per locus, while for parthenogens the number of alleles ranged from three to 10. The levels of heterozygosity in A. franciscana and in parthenogens ranged from 0.115 to 0.976 and from 0.000 to 0.971, respectively. These microsatellite loci showed a high population assignment power, which will be useful for future studies of population genetics and invasive processes in Artemia
Abstract: The meridional serotine bat Eptesicus isabellinus is found in North Africa and the Iberian Peninsula. We analyzed the genetic structure of E. isabellinus at two different geographic scales to reveal the historical and ecological patterns that have shaped its populations. The role of the Straits of Gibraltar as an isolating barrier between African and Iberian populations is evaluated and the degree of genetic structure and female-mediated gene flow was assessed at a local scale between neighboring colonies. Populations of E. isabellinus from Iberia and northern Morocco show little genetic divergence and share mtDNA haplotypes, indicating that the Straits of Gibraltar are neither an impediment to dispersal nor a cause of genetic differentiation. Our results also suggest that E. isabellinus may have dispersed from western Andalusia into northern Morocco after the last glacial period. At a smaller geographic scale, the colonies studied showed high variation in genetic variability and structure, indicating that no female-mediated gene flow is present. This pattern is consistent with a described pattern of independent endemic viral circulation of the bat rabies virus EBLV-1, which was found when studying rabies dynamics in the same serotine bat colonies
Abstract: There has been a recent appreciation of the ecological impacts of zooplanktonic species invasions. The North American brine shrimp Artemia franciscana is one such alien invader in hyper-saline water ecosystems at a global scale. It has been shown to outcompete native Artemia species, leading to their local extinction. We used partial sequences of the mitochondrial Cytochrome c Oxidase Subunit 1 (COI or cox1) gene to investigate the genetic diversity and phylogeography of A. salina, an extreme halophilic sexual brine shrimp, over its known distribution range (Mediterranean Basin and South Africa) and to assess the extent of local endemism, the degree of population structure and the potential impact of traditional human saltpan management on this species. We also examined the phylogenetic relationships in the genus Artemia using COI sequences. Our results show extensive regional endemism and indicate an early Pleistocene expansion of A. salina in the Mediterranean Basin. Subsequent population isolation in a mosaic of Pleistocene refugia is suggested, with two or three refugia located in the Iberian Peninsula. Two instances of longdistance colonization were also observed. Surprisingly, given its strong phylogeographical structure, A. salina showed a signature of correlation between geographical and genetic distance. Owing to strong ‘priority effects’, extensive population differentiation is retained, despite dispersal via migrant birds and human management of saltpans. The foreseeable expansion of A. franciscana is likely to be followed by substantial loss of genetic diversity in Mediterranean A. salina. Large genetic divergences between Mediterranean and South African A. salina suggest that the latter deserves species status
Abstract: The region around the Strait of Gibraltar is considered to be one of the most relevant ‘hot spots’ of biodiversity in the Mediterranean Basin due to its historical, biogeographical, and ecological features. Prominent among these is its role as a land bridge for the migration and differentiation of species during the Pleistocene, as a consequence of the lowering of sea level and climate changes associated with the Ice Ages. In the present study, we report a multilevel hierarchical investigation of the genetic diversity of Calicotome villosa, a common pioneer legume shrub, at the regional scale. The results of genetic analysis of progeny arrays are consistent with a predominantly outcrossing mating system in all the populations analysed. Geographically, a pattern of population isolation by distance was found, but the Strait accounted for only approximately 2% of the among-population genetic differentiation. Consequently, extensive historical gene flow appears to be the rule for this species in this area. According to the natural history traits of C. villosa (pollination, dispersal, and colonization ability), we hypothesize that gene flow must be strongly influenced by seed dispersal because pollen flow is very limited. Based on the history of trade and land use, cattle and human movements across the Strait must have strongly favoured seed dispersal. We review and discuss these results and compare them with those of other reported studies of genetic and phylogenetic differentiation across the Strait of Gibraltar. It is stressed that colonization ability, which depends upon seed dispersal and life form, can be a more critical factor in gene flow than pollination
Abstract: Here we study genetic differentiation and changes over time in genetic variability in the rare pine marten Martes martes. Samples from three isolated geographic regions: Jutland and Sealand (Denmark) and southern Scania (southernmost Sweden), were genotyped by sequencing the hypervariable domain of the mitochondria control region. Both recent and museum samples were analysed in order to evaluate any temporal loss of genetic variability. Eight haplotypes were found. Two were main haplotypes shared by individuals from all three regions, and in all localities unique haplotypes were found. When comparing the data with previous haplotype analysis, our results suggest that at least three different haplotype groups exist in central and Northern Europe, with the samples from southern Scania being differentiated from samples previously analysed from central Sweden, and the genotypic data for Jutland and Sealand suggest a recent independent evolutionary history for the Danish pine marten
Abstract: We describe the application of a simple, low-cost, and effective method of DNA extraction (hot sodium hydroxide and Tris, HotSHOT) to the diapausing propagules of continental aquatic invertebrates for its use in PCR amplification. We illustrate the use of the technique in cladocerans, rotifers, anostracans, notostracans, and copepod diapausing eggs. We compare the performance of the HotSHOT technique to the currently most widely used method for DNA extraction of zooplankton eggs and individuals, the chelating resin (or Chelex) technique. The HotSHOT technique overcomes several of the problems posed by Chelex and permits easy optimization for its use with 96-well plates for high-throughput DNA extraction and subsequent genetic characterization. We foresee a wide use of this technique in the future from DNA barcoding of diapausing stages to the genetic characterization of the diapausing egg banks of continental aquatic invertebrates
Abstract: A spatio-temporal study of genetic variation in the Danish pine marten (Martes martes) populations from the Jutland peninsula and from the island of Sealand was performed using 11 microsatellite markers. Samples obtained from 1892 to 2003 were subdivided into historical (prior to 1970) and recent (from 1970) groups. As compared with the historical samples, there was a significant loss of genetic variation in the recent Jutland population, but not in Sealand. Effective population sizes were estimated using Bayesian-based software (TMVP). Historical effective population sizes were 5897 (90% highest probability density, HPD, limits: 1502–6849) in Jutland and 1300 (90% HPD limits: 224–5929) in Sealand, whereas recent effective population sizes were 14.7 (90% HPD limits: 10.9–23.5) in Jutland and 802 (90% HPD limits: 51.8–5510) in Sealand. Significant genetic differentiation (FST) was found between the two historical samples, between the two recent samples, and between the historical and the recent sample in Jutland; whereas the FST value between the historical and the recent sample in Sealand was not significant. The significant genetic differentiation between the historical and the recent samples indicates changes in the genetic compositions over time, and the higher FST values between the two recent samples, as compared with the two historical samples, indicates that the populations in Sealand and Jutland have drifted apart within a short time span. No deviation from Hardy–Weinberg equilibrium was found within populations, indicating no further substructuring
Abstract: We describe 12 new polymorphic dinucleotide microsatellite loci and multiplex Polymerase Chain Reaction conditions from the loggerhead sea turtle Caretta caretta. Levels of polymorphism were assessed in 50 individuals from the nesting population of the Cape Verde Islands. Number of alleles ranged from 3 to 13 (average of 7.33) and the values of observed heterozygosities from 0.32 to 0.80 (average of 0.61). Cross-species amplification on three other marine turtles, Chelonia mydas, Eretmochelys imbricata and Dermochelys coriacea, revealed polymorphism and variability at eight, eleven and three loci,respectively
Abstract: Recent papers mention ideas on the topics of biodiversity conservation strategies and priorities (Redford et al. 2003; Lamoreux et al. 2006; Rodrı´guez et al. 2006), the current status of biodiversity (Loreau et al. 2006), the obligations of conservation biologists regarding management policies (Chapron 2006; Schwartz 2006), and the main threats to biodiversity (including invasive species) (Bawa 2006). I suggest, however, that these articles do not really deal with biodiversity. Rather, they all focus on a few obviously charismatic groups (mammals, birds, some plants, fishes, human culture). Mammals and birds have traditionally been proposed as umbrella or flagship species (‘‘species that needs such large tracts of habitat that saving it will automatically save many other species’’––Simberloff 1998), to identify areas suitable as nature reserves (Kerr 1997; Sergio et al. 2005). In the following I give an example where the strategy of using umbrella species (normally a charismatic large vertebrate) can fail in the conservation of many uncharismatic groups and endemic species. It is recognized that the systematic and conservation status of invertebrates are not well documented, and that yet they are in more severe danger than other groups in nature. As the World Conservation Union (IUCN) indicates: ‘‘Most animal species in nature are invertebrates, and the overwhelming majority of threatened species are likely to be invertebrates. But very little has been assessed on this group to infer about its conservation status’’
Abstract: The Andalusian hemipode (Turnix sylvatica sylvatica) (Order: Turniciformes, Family: Turnicidae), formerly distributed in several Mediterranean countries, is a critically endangered bird, if not already extinct. Subspecies of the T. sylvatica complex, in turn composed by nine subspecies are widely distributed in Africa and southern Asia. The last free-ranging Andalusian hemipodes were shot by hunters near Don˜ ana National Park (Spain) in 1981. Therefore, this species could be the last bird species getting extinct in Iberia and Europe in the XXth century. This investigation deals with the phylogenetic relationships of the Andalusian hemipode with the supposedly congeneric T. varia, T. tanki, T. suscitator and T. pyrrhothorax, and with the supposedly conspecific T. sylvatica lepurana, which is the geographically nearest buttonquail population (occurring in central and southern Africa). A 606 bp long fragment of the cytochrome b gene (approx. 1140 bp) of the mitochondrial DNA was sequenced, using both museum skins (the only available source for T. s. sylvatica) or blood/tissue samples from contemporary individuals (remaining species and subspecies). Seven haplotypes were found: two each for T. varia and T. s. lepurana, and one each for T. tanki, T. suscitator, T. pyrrhothorax, and T. s. sylvatica. Sequence divergence values obtained from pairwise distances between the T. sylvatica group haplotypes and the other species, ranged from 19.4 to 25.9%. The low genetic divergence between T. s. sylvatica and T. s. lepurana (0.00–0.01%) confirmed that the current classification based on morphological characters is correct, and that these two taxa may should be considered as subspecies. This close relationship would permit an introduction T. sylvatica where the species was last seen in Spain (i.e., Doñana National Park). This area is now strictly protected and human persecution is no longer a problem
Abstract: Long-eared bats of the genus Plecotus are widespread and common over most of the western Palaearctic. Based on recent molecular evidence, they proved to represent a complex of several cryptic species, with three new species being described from Europe in 2002. Evolutionary relationships among the different lineages are still fragmentary because of the limited geographic coverage of previous studies. Here we analyze Plecotus mitochondrial DNA sequences from the entire Mediterranean region and Atlantic Islands. Phylogenetic reconstructions group these western Palaearctic Plecotus into two major clades which split at least 5 Myr ago and that are each subdivided into further subgroups. An auritus group includes the traditional P. auritus species and its sister taxon P. macrobullaris (=P. alpinus) plus related specimens from the Middle East. P. auritus and P. macrobullaris have broadly overlapping distributions in Europe, although the latter is apparently more restricted to mountain ranges. The other major clade, the austriacus group, includes the European species P. austriacus and at least two other related taxa from North Africa (including P. teneriffae from the Canary Islands), the Balkans and Anatolia (P. kolombatovici). The sister species of this austriacus group is P. balensis, an Ethiopian endemic. Phylogenetic reconstructions further suggest that P. austriacus reached Madeira during its relatively recent westwards expansion through Europe, while the Canary Islands were colonized by a North African ancestor. Although colonization of the two groups of Atlantic Islands by Plecotus bats followed very distinct routes, neither involved lineages from the auritus group. Furthermore, the Strait of Gibraltar perfectly segregates the distinct lineages, which confirms its key role as a geographic barrier. This study also stresses the biogeographical importance of the Mediterranean region, and particularly of North Africa, in understanding the evolution of the western Palaearctic biotas
Abstract: We use two mitochondrial DNA fragments with different substitution rates (cytochrome b gene and the control region) to address the following phylogeographic questions about western Palaearctic populations of the barbastelle bat (Barbastella barbastella): 1) Do the Iberian populations of barbastelles show any genetic discontinuity associated with its present fragmented distribution?, 2) Is the Gibraltar Strait an effective barrier to gene flow for barbastelle) and 3) Is the subspecies from the Canary Islands genetically distinct from continental barbastelle? Our molecular survey shows that there is only a shallow genetic structure among populations of the Iberian Peninsula and Morocco, and probably, even across Europe until Thrace, although this last point needs to be confirmed. The Gibraltar Strait has not played any significant role as a biogeographic barrier to prevent the recent passage of European barbastelles to Morocco (or vice versa). Our phylogenetic reconstructions also confirm the taxonomic distinction of B. barbastellus guanchae as an endemic subspecies confined to the Canary Islands. The precise origin of this Canarian taxon is, nevertheless, still unclear as its mitochondrial lineage is distinct from any lineage found so far in Morocco and Iberia. This important genetic distinctness suggests either a relatively ancient colonization of the Canary Islands or that the source population of the founders have not yet been identified.
Abstract: During heart surgery, myocardial dysfunction may occasionally appear when extracorporeal circulation is discontinued, causing serious haemodynamic disorders. Many mechanisms are involved in this hypoxia-reoxygenation syndrome. The aim of this experimental study was to characterize the vasomotor disorders that take place in the isolated porcine coronary artery during in vitro hypoxia-reoxygenation and to analyse the effect of nifedipine on them. Rings of porcine coronary artery were placed in an organ chamber connected to a system that recorded isometric forces. The vascular rings were divided into two groups: control group (no nifedipine) and study group (nifedipine, 10-6 mol/l). The vascular rings were precontracted with 30 mmol/l KCl and then hypoxia-reoxygenation was induced. Control arterial rings showed important changes in coronary vasomotor tone: severe hypoxic contraction (from 14.48-1.16 g of stable contraction to 17.6-0.44 g after the imposition of hypoxia), and transient vasodilation during reoxygenation (69.9-10.1% of the maximum contraction achieved). The nifedipine group experienced a slow, progressive, vasodilation throughout the whole experiment (73-3.5% of the maximum contraction). Neither hypoxic vasospasm nor fluctuations of the coronary vascular tone occurred. Thus, at the end of the hypoxia, the control vessels presented a degree of contraction similar to the initial level. However, in the rings treated with nifedipine, the percentage of dilation was 73-3.5% (P<0.05). In the isolated porcine coronary artery with intact endothelium undergoing a situation of hypoxia-reoxygenation, we have detected transient vasoconstriction during the first period of hypoxia, followed by vasodilation during reoxygenation. The intracoronary administration of nifedipine prior to the imposition of hypoxia prevents hypoxic contraction, achieving a greater and more stable degree of coronary vasorelaxation during the complete process of hypoxia-reoxygenation.
Abstract: Background:
We studied the alterations produced in left ventricular systolic and diastolic function after applying a protocol of cryopreservation at subzero temperatures. Isolated rabbit hearts were used for the study with 5% polyethylene glycol (PM 4000) being the cryoprotective agent.
Material and method:
The cryoprotectant solution CP-16 was used on the explanted heart in three phases: induction, storage and thawing. After 60 minutes at –1.6 °C and thawing at 2.7 °C/min, the heart was connected to a Langendorff system and perfused anterogradely with Krebs-Henseleit buffer. We analyzed the systolic and diastolic parameters before and after cryopreservation, thereby establishing a comparative statistical study.
Results:
Following cryopreservation we found a statistically significant increase (p < 0.05) in the peak and developed pressure of the left ventricle with an upward, left displacement of the ventricular function curve. This is indicative of improvement in systolic function. However, the diastolic function showed worsening, with a statistically significant increase (p < 0.05) in mean stiffness, decrease in differential stiffness (p < 0.05) and upward, left displacement of the diastolic pressure-volume curve.
Conclusions:
On the basis of our results we concluded that: a) PM 4000 polyethylene glycol maintains the heart biological viability during cryopreservation at subzero temperatures, and b) after an cryopreservation left ventricular diastolic function worsens with an increase in systolic function
Abstract: Background:
We have studied the alterations produced in the diastolic function of the left ventricle after applying a protocol of cryopreservation at subzero temperatures.
Methods:
Isolated rabbit hearts and 5% polyethylene glycol (PM 4000) as the cryoprotective agent were used for the study.
Results-Conclusions:
Following cryopreservation we found a statistically significant increase in systolic function. However, the diastolic function shows worsening, with a statistically significant increase (p < 0.05) in mean stiffness, decrease in differential stiffness, (p < 0.05) and upward and leftward displacement of the diastolic pressurevolume curve