The maternal health behaviours of non-Irish nationals during pregnancy and the effect of time living in Ireland.

OBJECTIVES: Maternal health behaviours (MHBs) can influence pregnancy outcomes. Despite efforts internationally to encourage positive MHBs, women often fail to comply with pregnancy guidelines. International studies show differences in MHBs between nationalities and an effect of time spent in the host country. There is limited Irish data in this area, with no previous research relating to the effect of time in Ireland. STUDY DESIGN: This study is a cross-sectional analysis of the Growing Up in Ireland infant cohort, a nationally representative longitudinal study. METHODS: Examination of the MHBs of non-Irish nationals during pregnancy and the effect of time in Ireland on the said behaviours. RESULTS: An association was found between time spent in Ireland and increased alcohol consumption prevalence. Those living in Ireland for ≤5 years were 60.8% less likely to consume alcohol during pregnancy (0.000) and 29.3% less likely to take folic acid before conception (0.021). Those who smoked during pregnancy were 98.6% more likely to consume alcohol (0.000) and those who consumed alcohol were 95.2% more likely to smoke during pregnancy (0.000). CONCLUSIONS: The results demonstrate differences in MHBs and the influence of time living in Ireland. These findings are of relevance for policy and intervention planning to optimise pregnancy outcomes among non-nationals.

Characterization of copy number variants in a large multibreed population of beef and dairy cattle using high-density single nucleotide polymorphism genotype data.

Copy number variants (CNVs) are a form of genomic variation that changes the structure of the genome through deletion or duplication of stretches of DNA. The objective of the present study was to characterize CNVs in a large multibreed population of beef and dairy bulls. The CNVs were called on the autosomes of 5,551 cattle from 22 different beef and dairy breeds, using 2 freely available software suites, QuantiSNP and PennCNV. All CNVs were classified into either deletions or duplications. The median concordance between PennCNV and QuantiSNP, per animal, was 18.5% for deletions and 0% for duplications. The low concordance rate between PennCNV and QuantiSNP indicated that neither algorithm, by itself, could identify all CNVs in the population. In total, PennCNV and QuantiSNP collectively identified 747,129 deletions and 432,523 duplications; 80.2% of all duplications and 69.1% of all deletions were present only once in the population. Only 0.154% of all CNVs identified were present in more than 50 animals in the population. The distribution of the percentage of the autosomes that were composed of deletions, per animal, was positively skewed, as was the distribution for the percentage of the autosomes that were composed of duplications, per animal. The first quartile, median, and third quartile of the distribution of the percentage of the autosomes that were composed of deletions were 0.019%, 0.037%, and 0.201%, respectively. The first quartile, median, and third quartile of the distribution of the percentage of the autosomes that were composed of duplications were 0.013%, 0.028%, and 0.076%, respectively. The distributions of the number of deletions and duplications per animal were both positively skewed. The interquartile range for the number of deletions per animal in the population was between 16 and 117, whereas for duplications it was between 8 and 23. Per animal, there tended to be twice as many deletions as duplications. The distribution of the length of deletions was positively skewed, as was the distribution of the length of duplications. The interquartile range for the length of deletions in the population was between 25 and 101 kb, and for duplications the interquartile range was between 46 and 235 kb. Per animal, duplications tended to be twice as long as deletions. This study provides a description of the characteristics and distribution of CNVs in a large multibreed population of beef and dairy cattle.

Comparison of bone marrow component removal from processed femoral head bone from living and deceased donors: presence of geodes in living donor bone can prevent maximum removal of marrow components.

NHS Blood and Transplant Tissue and Eye Services banks and issues, cut, shaped and washed bone from deceased donors. The bone is cut/shaped prior to washing and then processed to remove up to 99.9% of blood, bone marrow and associated cells. The processed bone is then sterilised by gamma irradiation with or without a freeze-drying step. Removal of donor blood and bone marrow has been reported to aid incorporation of allograft bone without affecting the biomechanical properties of the bone. However, cut and shaped bone is not suitable for some orthopaedic procedures and some orthopaedic surgeons do not wish to use irradiated bone. Therefore, Tissue and Eye Services have also developed a method for washing intact femoral head bone, from living and deceased donors. We have observed that processing of intact femoral head bone does not always result in removal of 99% (or above) of marrow components and can be as low as 93% removal. We have examined washed femoral head bone and found the presence of internal fluid-filled cysts within subchondral cancellous bone in bone from living donors. The cysts have been identified as geodes and we suggest that these geodes may be responsible for the reduction in bone marrow component removal in living donor bone during processing.

Assessment of the permeability properties of cryopreservation outer bags used in NHSBT.

This study was carried out to investigate leakage/transport across the bag material of six outer cryopreservation bags in common use within NHS Blood and Transplant. In order to do this two different leak testing procedures; coloured dye and hydrogen tracer gas, were used. The data obtained show that a coloured dye cannot permeate through the materials both at room temperature and following storage at liquid nitrogen temperature (- 196 °C). In addition, when filled with the smallest elemental molecule, hydrogen, in the form of a tracer gas, all of the bags only allowed trace amounts of hydrogen to escape, either through the seal or the bag material. The data indicated that each of the bag materials tested would be capable of preventing bacterial or viral cross-contamination as long as the material remained intact.

In vitro biomechanical and hydrodynamic characterisation of decellularised human pulmonary and aortic roots.

BACKGROUND AND PURPOSE OF THE STUDY: The use of decellularised biological heart valves in the replacement of damaged heart valves offers a promising solution to reduce the degradation issues associated with existing cryopreserved allografts. The purpose of this study was to assess the effect of low concentration sodium dodecyl sulphate decellularisation on the in vitro biomechanical and hydrodynamic properties of cryopreserved human aortic and pulmonary roots. METHOD: The biomechanical and hydrodynamic properties of cryopreserved decellularised human aortic and pulmonary roots were fully characterised and compared to cellular human aortic and pulmonary roots in an unpaired study. Following review of these results, a further study was performed to investigate the influence of a specific processing step during the decellularisation protocol ('scraping') in a paired comparison, and to improve the method of the closed valve competency test by incorporating a more physiological boundary condition. RESULTS: The majority of the biomechanical and hydrodynamic characteristics of the decellularised aortic and pulmonary roots were similar compared to their cellular counterparts. However, several differences were noted, particularly in the functional biomechanical parameters of the pulmonary roots. However, in the subsequent paired comparison of pulmonary roots with and without decellularisation, and when a more appropriate physiological test model was used, the functional biomechanical parameters for the decellularised pulmonary roots were similar to the cellular roots. CONCLUSION: Overall, the results demonstrated that the decellularised roots would be a potential choice for clinical application in heart valve replacement.

Development and characterisation of a large diameter decellularised vascular allograft.

The aims of this study were to develop a biological large diameter vascular graft by decellularisation of native human aorta to remove the immunogenic cells whilst retaining the essential biomechanical, and biochemical properties for the ultimate benefit of patients with infected synthetic grafts. Donor aortas (n = 6) were subjected to an adaptation of a propriety decellularisation process to remove the cells and acellularity assessed by histological analysis and extraction and quantification of total DNA. The biocompatibility of the acellular aortas was determined using standard contact cytotoxicity tests. Collagen and denatured collagen content of aortas was determined and immunohistochemistry was used to determine the presence of specific extracellular matrix proteins. Donor aortas (n = 6) were divided into two, with one half subject to decellularisation and the other half retained as native tissue. The native and decellularised aorta sections were then subject to uniaxial tensile testing to failure [axial and circumferential directions] and suture retention testing. The data was compared using a paired t-test. Histological evaluation showed an absence of cells in the treated aortas and retention of histoarchitecture including elastin content. The decellularised aortas had less than 15 ng mg-1 total DNA per dry weight (mean 94% reduction) and were biocompatible as determined by in vitro contact cytotoxicity tests. There were no gross changes in the histoarchitecture [elastin and collagen matrix] of the acellular aortas compared to native controls. The decellularisation process also reduced calcium deposits within the tissue. The uniaxial tensile and suture retention testing revealed no significant differences in the material properties (p > 0.05) of decellularised aorta. The decellularisation procedure resulted in minimal changes to the biological and biomechanical properties of the donor aortas. Acellular donor aorta has excellent potential for use as a large diameter vascular graft.

Assessment of a closed wash system developed for processing living donor femoral heads.

NHS Blood and Transplant Tissue and Eye Services (TES) and Scottish National Blood Transfusion Services Tissues and Cells Directorate (TCD) currently bank whole, frozen femoral head bone from living donors who are undergoing primary hip replacement surgery. When required, the bone is issued to a surgeon still frozen on dry ice (- 79 °C). Consequently, the femoral head bone is not processed, is not sterilised and at the time of issue, it contains donor blood, bone marrow and associated cells. We have previously shown that, cut, shaped and washed bone from deceased donors can be processed to remove up to 99.9% of blood, bone marrow and associated cells (Eagle et al. 2015). However, cut and shaped bone is not suitable for some orthopaedic procedures and some orthopaedic surgeons do not wish to use irradiated bone; therefore in this report, a method has been developed in which whole femoral heads can be washed to remove donor blood and bone marrow components. Processing results in excess of 99% bone marrow component removal-soluble protein, haemoglobin and DNA; the procedure is performed inside a closed system, thereby eliminating the need for terminal sterilisation by irradiation. In addition, uniaxial testing demonstrated no difference in compressive strength between washed and unwashed bone. We suggest that this washed bone may be capable of improving incorporation after grafting without disturbing biomechanical properties of the graft.

The efficacy and sterilisation of human decellularised dermal allografts with combinations of cupric ions and hydrogen peroxide.

Decellularised tissue allografts have been used in reconstructive surgical applications and transplantation for many years. Some of the current methods of sterilisation have a detrimental effect on the tissue graft structure and function. The anti-microbial activity of cupric ions and hydrogen peroxide (H2O2) are well known however their combined application is not currently utilised as a decontamination agent in the tissue banking world sector. The aim of this study was to determine the combined concentrations of copper chloride (CuCl2) and H2O2 that have the optimal bactericidal and sporicidal activity on decellularised (dCELL) human dermis. The first part of this study established the decimal reduction time (D-value) of CuCl2 (0.1 mg/L and 1 mg/L) together with H2O2 (0.01, 0.1, 0.5 and 1%) for Staphylococcus epidermidis, Escherichia coli and Bacillus subtilis spores. The second part of this study identified the most effective CuCl2 and H2O2 concentration that decontaminated dCELL human dermis inoculated with these pathogens. Of all the concentrations tested, 0.1 mg/L CuCl2 in combination with 1% H2O2 had the shortest D-value; S. epidermidis D = 3.15 min, E. coli D = 2.62 min and B. subtilis spores D = 18.05 min. However when adsorbed onto dCELL dermis, S. epidermidis and E. coli were more susceptible to 1 mg/L CuCl2 together with 0.5% H2O2. These studies show promise of CuCl2-H2O2 formulations as potential sterilants for decellularised dermal allografts.

Inference of population structure of purebred dairy and beef cattle using high-density genotype data.

Information on the genetic diversity and population structure of cattle breeds is useful when deciding the most optimal, for example, crossbreeding strategies to improve phenotypic performance by exploiting heterosis. The present study investigated the genetic diversity and population structure of the most prominent dairy and beef breeds used in Ireland. Illumina high-density genotypes (777 962 single nucleotide polymorphisms; SNPs) were available on 4623 purebred bulls from nine breeds; Angus (n=430), Belgian Blue (n=298), Charolais (n=893), Hereford (n=327), Holstein-Friesian (n=1261), Jersey (n=75), Limousin (n=943), Montbéliarde (n=33) and Simmental (n=363). Principal component analysis revealed that Angus, Hereford, and Jersey formed non-overlapping clusters, representing distinct populations. In contrast, overlapping clusters suggested geographical proximity of origin and genetic similarity between Limousin, Simmental and Montbéliarde and to a lesser extent between Holstein, Friesian and Belgian Blue. The observed SNP heterozygosity averaged across all loci was 0.379. The Belgian Blue had the greatest mean observed heterozygosity (HO=0.389) among individuals within breed while the Holstein-Friesian and Jersey populations had the lowest mean heterozygosity (HO=0.370 and 0.376, respectively). The correlation between the genomic-based and pedigree-based inbreeding coefficients was weak (r=0.171; P<0.001). Mean genomic inbreeding estimates were greatest for Jersey (0.173) and least for Hereford (0.051). The pair-wise breed fixation index (F st) ranged from 0.049 (Limousin and Charolais) to 0.165 (Hereford and Jersey). In conclusion, substantial genetic variation exists among breeds commercially used in Ireland. Thus custom-mating strategies would be successful in maximising the exploitation of heterosis in crossbreeding strategies.

Ultra-low-density genotype panels for breed assignment of Angus and Hereford cattle.

Angus and Hereford beef is marketed internationally for apparent superior meat quality attributes; DNA-based breed authenticity could be a useful instrument to ensure consumer confidence on premium meat products. The objective of this study was to develop an ultra-low-density genotype panel to accurately quantify the Angus and Hereford breed proportion in biological samples. Medium-density genotypes (13 306 single nucleotide polymorphisms (SNPs)) were available on 54 703 commercial and 4042 purebred animals. The breed proportion of the commercial animals was generated from the medium-density genotypes and this estimate was regarded as the gold-standard breed composition. Ten genotype panels (100 to 1000 SNPs) were developed from the medium-density genotypes; five methods were used to identify the most informative SNPs and these included the Delta statistic, the fixation (F st) statistic and an index of both. Breed assignment analyses were undertaken for each breed, panel density and SNP selection method separately with a programme to infer population structure using the entire 13 306 SNP panel (representing the gold-standard measure). Breed assignment was undertaken for all commercial animals (n=54 703), animals deemed to contain some proportion of Angus based on pedigree (n=5740) and animals deemed to contain some proportion of Hereford based on pedigree (n=5187). The predicted breed proportion of all animals from the lower density panels was then compared with the gold-standard breed prediction. Panel density, SNP selection method and breed all had a significant effect on the correlation of predicted and actual breed proportion. Regardless of breed, the Index method of SNP selection numerically (but not significantly) outperformed all other selection methods in accuracy (i.e. correlation and root mean square of prediction) when panel density was ⩾300 SNPs. The correlation between actual and predicted breed proportion increased as panel density increased. Using 300 SNPs (selected using the global index method), the correlation between predicted and actual breed proportion was 0.993 and 0.995 in the Angus and Hereford validation populations, respectively. When SNP panels optimised for breed prediction in one population were used to predict the breed proportion of a separate population, the correlation between predicted and actual breed proportion was 0.034 and 0.044 weaker in the Hereford and Angus populations, respectively (using the 300 SNP panel). It is necessary to include at least 300 to 400 SNPs (per breed) on genotype panels to accurately predict breed proportion from biological samples.

Evaluation of developed low-density genotype panels for imputation to higher density in independent dairy and beef cattle populations.

The objective of this study was to develop, using alternative algorithms, low-density SNP genotyping panels (384 to 12,000 SNP), which can be accurately imputed to higher-density panels across independent cattle populations. Single nucleotide polymorphisms were selected based on genomic characteristics (i.e., linkage disequilibrium [LD], minor allele frequency [MAF], and genomic distance) in a population of 1,267 Holstein-Friesian animals genotyped on the Illumina Bovine50 Beadchip (54,001 SNP). Single nucleotide polymorphism selection methods included 1) random; 2) equidistant location; 3) combination of SNP MAF and LD structure while maintaining relatively equal genomic distance between adjacent SNP; 4) a combination of high MAF, genomic distance between selected and candidate SNP, and correlation between genotypes of selected and candidate SNP; and 5) a machine learning algorithm. The panels were validated separately in 1) a population of 750 Holstein-Friesian animals with masked genotypes to reflect the lower-density SNP densities under investigation (1,249 animals with complete genotypes included in reference population) and 2) a population of 359 Limousin and Charolais cattle with high (777,962 SNP)-density genotypes (1,918 animals with complete genotypes included in the reference population). Irrespective of SNP selection method, imputation accuracy in both populations improved at a diminishing rate as the number of SNP included in the lower-density genotype panel increased. Additionally, the variability in mean imputation accuracy per individual decreased as the panel density increased. The SNP selection method had a major impact on the mean allele concordance rate, although its impact diminished as the panel density increased. Imputation accuracy for SNP selected using a combination of high SNP MAF, LD structure, and relatively equal genomic distance between SNP outperformed all other selection methods in densities < 12,000 SNP. Using this method of SNP selection, the correlation between the imputed and actual genotypes for the 3,000 SNP panel was 0.90 and 0.96 when applied to the beef and dairy populations, respectively; the respective correlations for the 6,000 SNP panel were 0.95 and 0.98. It is necessary to include between 3,000 and 6,000 SNP in a low-density panel to achieve adequate imputation accuracy to either medium density (approximately 50,000 SNP in the dairy population) or high density (approximately 700,000 SNP in the beef population) across diverse and independent populations.

Late effects in patients with Fanconi anemia following allogeneic hematopoietic stem cell transplantation from alternative donors.

Hematopoietic stem cell transplantation (HSCT) is curative for hematological manifestations of Fanconi anemia (FA). We performed a retrospective analysis of 22 patients with FA and aplastic anemia, myelodysplastic syndrome or acute myelogenous leukemia who underwent a HSCT at Memorial Sloan Kettering Cancer Center and survived at least 1 year post HSCT. Patients underwent either a TBI- (N=18) or busulfan- (N=4) based cytoreduction followed by T-cell-depleted transplants from alternative donors. Twenty patients were alive at time of the study with a 5- and 10-year overall survival of 100 and 84% and no evidence of chronic GvHD. Among the 18 patients receiving a TBI-based regimen, 11 (61%) had persistent hemochromatosis, 4 (22%) developed hypothyroidism, 7 (39%) had insulin resistance and 5 (27%) developed hypertriglyceridemia after transplant. Eleven of 16 evaluable patients (68%), receiving TBI, developed gonadal dysfunction. Two patients who received a TBI-based regimen died of squamous cell carcinoma. One patient developed hemochromatosis, hypothyroidism and gonadal dysfunction after busulfan-based cytoreduction. TBI appears to be a risk factor for malignant and endocrine late effects in the FA host. Multidisciplinary follow-up of patients with FA (including cancer screening) is essential for early detection and management of late complications, and improving long-term outcomes.

EVALUATION OF DMSO TRANSPORT IN HUMAN ARTICULAR CARTILAGE: VEHICLE SOLUTIONS AND EFFECTS ON CELL FUNCTION.

Osteochondral allografting techniques are limited by the availability of suitable donor tissue; there is an urgent need for effective cryopreservation. A fundamental requirement is the need to establish initial conditions of exposure to cryoprotectant that the chondrocytes will tolerate and that load the tissue with an adequate concentration of cryoprotectant. Three vehicle solutions to transport DMSO into the tissue were studied. Knee joints were obtained from deceased donors with appropriate consent. Whole condyles were treated with 20% w/w DMSO in each of three vehicle solutions and chondrocyte function and tissue CPA content measured. The results showed that exposure to 20% DMSO in each vehicle solution for 2 hours at 0 degrees C was tolerated without loss of GAG synthetic activity. It was observed that penetration of DMSO increased little after 1 hour of CPA exposure at 0 degrees C but the final tissue concentration of CPA was markedly lower than that in the medium.

A liquidus tracking approach to the cryopreservation of human cartilage allografts.

In the "liquidus tracking" (LT) approach to cryopreservation both the temperature and the concentration of cryoprotectant (CPA) are controlled such that solution composition "tracks" the liquidus (melting point) line for that system. Ice crystal formation is prevented but the tissue is not exposed to CPA concentrations exceeding those experienced by cells during conventional cryopreservation. This approach is particularly appropriate for articular cartilage because chondrocytes in situ are exquisitely susceptible to damage by the crystallisation of ice. This project aimed to develop a suitable process for tissue to be used in the surgical repair of damaged human knee joints. A high proportion of the chondrocytes should be alive. Human articular cartilage was obtained from deceased donors and dimethyl sulphoxide (DMSO) was used as the CPA, cooling was at 0.14°C/min and warming at 0.42°C/min. The vehicle solution was CPTes2. A program of increasing DMSO concentration was developed for cooling and this gave satisfactory tissue concentrations but reduction of DMSO concentration during warming was inadequate, resulting in higher tissue concentrations than required. Biomechanical testing indicated a compressive modulus of 9.5±1.3 MPa in LT-processed cartilage, with control values of 11.6±0.8 MPa (p>0.05, Student's t-test). Measurement of GAG synthesis sometimes approached 65% or 85% of control, but the variability of replicate data prevented firm conclusions. Ideally allograft tissue should score 1A or above on the Noyes scale and the donor age should be less than 46 years but the cartilage used in this study did not meet these standards.

Validation of cold chain shipping environment for transport of allografts as part of a human tissue bank returns policy.

Human tissue is shipped to surgeons in the UK in either a freeze-dried or frozen state. To ensure quality and safety of the tissue, frozen tissue must be shipped in insulated containers such that tissue is maintained at an appropriate temperature. UK Blood Transfusion Service regulations state "Transportation systems must be validated to show maintenance of the required storage temperature" and also state that frozen, non-cryopreserved tissue "must be transported… at -20 °C or lower" (Guidelines for the Blood Transfusion Services in the United Kingdom, 8th Edn. 2013). To maintain an expiry date for frozen tissue longer than 6 months, the tissue must be maintained at a temperature of -40 °C or below. The objective of this study was to evaluate and validate the capability of a commercially available insulated polystyrene carton (XPL10), packed with dry ice, to maintain tissue temperature below -40 °C. Tissue temperature of a single frozen femoral head or a single frozen Achilles tendon, was recorded over a 4-day period at 37 °C, inside a XPL10 carton with dry ice as refrigerant. The data demonstrate that at 37 °C, the XPL10 carton with 9.5 kg of dry ice maintained femoral head and tendon tissue temperature below -55 °C for at least 48 h; tissue temperature did not rise above -40 °C until at least 70 h. Data also indicated that at a storage temperature lower than 37 °C, tissue temperature was maintained for longer periods.

Development of a terminally sterilised decellularised dermis.

Many of the decellularised dermis products on the market at present are aspectically produced. NHS Blood and Transplant Tissue Services have developed a method of producing a dCELL human dermis which has been terminally sterilised by gamma irradiation. The terminally sterilised decellularised dermis was compared with cellular tissue and examined for histology, residual DNA content, biomechanical and biochemical properties, in vitro cytotoxicity and in vivo implantation in a mouse model. No alterations in morphology as viewed by light microscopy were observed and DNA removal was 99%. There were no significant changes in ultimate tensile stress or evidence for collagen denaturation or cytotoxicity. The in vivo studies did not indicate any adverse tissue reactions in the mouse model and demonstrated incorporation of dCELL human dermis into the host. Decellularisation, followed by terminal sterilisation with gamma irradiation, is an appropriate method to produce a human dermis allograft material suitable for transplantation.