Resurrection of a Bull by Cloning from Organs Frozen without Cryoprotectant in a −80°C Freezer for a Decade

Frozen animal tissues without cryoprotectant have been thought to be inappropriate for use as a nuclear donor for somatic cell nuclear transfer (SCNT). We report the cloning of a bull using cells retrieved from testicles that had been taken from a dead animal and frozen without cryoprotectant in a −80°C freezer for 10 years. We obtained live cells from defrosted pieces of the spermatic cords of frozen testicles. The cells proliferated actively in culture and were apparently normal. We transferred 16 SCNT embryos from these cells into 16 synchronized recipient animals. We obtained five pregnancies and four cloned calves developed to term. Our results indicate that complete genome sets are maintained in mammalian organs even after long-term frozen-storage without cryoprotectant, and that live clones can be produced from the recovered cells

B-cell lymphoma in retrieved femoral heads: a long term follow up

<p>Abstract</p> <p>Background</p> <p>A relatively high incidence of pathological conditions in retrieved femoral heads, including a group of patients having low grade B-cell lymphoma, has been described before. At short term follow up none of these patients with low-grade B-cell lymphoma showed evidence of systemic disease. However, the long term follow up of these patients is not known.</p> <p>Methods</p> <p>From November 1994 up to and including December 2005 we screened all femoral heads removed at the time of primary total hip replacement histopathologically and included them in the bone banking protocol according to the guidelines of the American Associations of Tissue Banks (AATB) and the European Association of Musculo-Skeletal Transplantation (EAMST). We determined the percentage of B-cell lymphoma in all femoral heads and in the group that fulfilled all criteria of the bone banking protocol and report on the long-term follow-up.</p> <p>Results</p> <p>Of 852 femoral heads fourteen (1.6%) were highly suspicious for low-grade B-cell lymphoma. Of these 852 femoral heads, 504 were eligible for bone transplantation according to the guidelines of the AATB and the EAMST. Six femoral heads of this group of 504 were highly suspicious for low-grade B-cell lymphoma (1.2%). At long term follow up two (0.2%) of all patients developed systemic malignant disease and one of them needed medical treatment for her condition.</p> <p>Conclusion</p> <p>In routine histopathological screening we found variable numbers of low-grade B-cell lymphoma throughout the years, even in a group of femoral heads that were eligible for bone transplantation. Allogenic transmission of malignancy has not yet been reported on, but surviving viruses are proven to be transmissible. Therefore, we recommend the routine histopathological evaluation of all femoral heads removed at primary total hip arthroplasty as a tool for quality control, whether the femoral head is used for bone banking or not.</p

Sterilization of allograft bone: effects of gamma irradiation on allograft biology and biomechanics

Gamma irradiation from Cobalt 60 sources has been used to terminally sterilize bone allografts for many years. Gamma radiation adversely affects the mechanical and biological properties of bone allografts by degrading the collagen in bone matrix. Specifically, gamma rays split polypeptide chains. In wet specimens irradiation causes release of free radicals via radiolysis of water molecules that induces cross-linking reactions in collagen molecules. These effects are dose dependent and give rise to a dose-dependent decrease in mechanical properties of allograft bone when gamma dose is increased above 25 kGy for cortical bone or 60 kGy for cancellous bone. But at doses between 0 and 25 kGy (standard dose), a clear relationship between gamma dose and mechanical properties has yet to be established. In addition, the effects of gamma radiation on graft remodelling have not been intensively investigated. There is evidence that the activity of osteoclasts is reduced when they are cultured onto irradiated bone slices, that peroxidation of marrow fat increases apoptosis of osteoblasts; and that bacterial products remain after irradiation and induce inflammatory bone resorption following macrophage activation. These effects need considerably more investigation to establish their relevance to clinical outcomes. International consensus on an optimum dose of radiation has not been achieved due to a wide range of confounding variables and individual decisions by tissue banks. This has resulted in the application of doses ranging from 15 to 35 kGy. Here, we provide a critical review on the effects of gamma irradiation on the mechanical and biological properties of allograft bone

Invasive plants and their escape from root herbivory: a worldwide comparison of the root-feeding nematode communities of the dune grass Ammophila arenaria in natural and introduced ranges

Invasive plants generally have fewer aboveground pathogens and viruses in their introduced range than in their natural range, and they also have fewer pathogens than do similar plant species native to the introduced range. However, although plant abundance is strongly controlled by root herbivores and soil pathogens, there is very little knowledge on how invasive plants escape from belowground enemies. We therefore investigated if the general pattern for aboveground pathogens also applies to root-feeding nematodes and used the natural foredune grass Ammophila arenariaas a model. In the late 1800s, the European A. arenariawas introduced into southeast Australia (Tasmania), New Zealand, South Africa, and the west coast of the USA to be used for sand stabilization. In most of these regions, it has become a threat to native vegetation, because its excessive capacity to stabilize wind-blown sand has changed the geomorphology of coastal dunes. In stable dunes of most introduced regions, A. arenaria is more abundant and persists longer than in stabilized dunes of the natural range. We collected soil and root samples and used additional literature data to quantify the taxon richness of root-feeding nematodes on A.?arenaria in its natural range and collected samples from the four major regions where it has been introduced. In most introduced regions A. arenaria did not have fewer root-feeding nematode taxa than the average number in its natural range, and native plant species did not have more nematode taxa than the introduced species. However, in the introduced range native plants had more feeding-specialist nematode taxa than A. arenaria and major feeding specialists (the sedentary endoparasitic cyst and root knot nematodes) were not found on A. arenaria in the southern hemisphere. We conclude that invasiveness of A. arenaria correlates with escape from feeding specialist nematodes, so that the pattern of escape from root-feeding nematodes is more alike escape from aboveground insect herbivores than escape from aboveground pathogens and viruses. In the natural range of A. arenaria, the number of specialist-feeding nematode taxa declines towards the margins. Growth experiments are needed to determine the relationship between nematode taxon diversity, abundance, and invasiveness of A. arenaria. [KEYWORDS: Ammophila arenaria ; Ammophila breviligulata ; biotic resistance hypothesis ; enemy escape hypothesis ; feeding specialist ; invasive plant ; root herbivore ; soil pathogen]