Single cell RNA-sequencing and RNA-tomography of the avian embryo extending body axis.

Introduction: Vertebrate body axis formation initiates during gastrulation and continues within the tail bud at the posterior end of the embryo. Major structures in the trunk are paired somites, which generate the musculoskeletal system, the spinal cord-forming part of the central nervous system, and the notochord, with important patterning functions. The specification of these different cell lineages by key signalling pathways and transcription factors is essential, however, a global map of cell types and expressed genes in the avian trunk is missing. Methods: Here we use high-throughput sequencing approaches to generate a molecular map of the emerging trunk and tailbud in the chick embryo. Results and Discussion: Single cell RNA-sequencing (scRNA-seq) identifies discrete cell lineages including somites, neural tube, neural crest, lateral plate mesoderm, ectoderm, endothelial and blood progenitors. In addition, RNA-seq of sequential tissue sections (RNA-tomography) provides a spatially resolved, genome-wide expression dataset for the avian tailbud and emerging body, comparable to other model systems. Combining the single cell and RNA-tomography datasets, we identify spatially restricted genes, focusing on somites and early myoblasts. Thus, this high-resolution transcriptome map incorporating cell types in the embryonic trunk can expose molecular pathways involved in body axis development.

Chromosome-level genome sequence of the Genetically Improved Farmed Tilapia (GIFT, Oreochromis niloticus) highlights regions of introgression with O. mossambicus.

BACKGROUND: The Nile tilapia (Oreochromis niloticus) is the third most important freshwater fish for aquaculture. Its success is directly linked to continuous breeding efforts focusing on production traits such as growth rate and weight. Among those elite strains, the Genetically Improved Farmed Tilapia (GIFT) programme initiated by WorldFish is now distributed worldwide. To accelerate the development of the GIFT strain through genomic selection, a high-quality reference genome is necessary. RESULTS: Using a combination of short (10X Genomics) and long read (PacBio HiFi, PacBio CLR) sequencing and a genetic map for the GIFT strain, we generated a chromosome level genome assembly for the GIFT. Using genomes of two closely related species (O. mossambicus, O. aureus), we characterised the extent of introgression between these species and O. niloticus that has occurred during the breeding process. Over 11 Mb of O. mossambicus genomic material could be identified within the GIFT genome, including genes associated with immunity but also with traits of interest such as growth rate. CONCLUSION: Because of the breeding history of elite strains, current reference genomes might not be the most suitable to support further studies into the GIFT strain. We generated a chromosome level assembly of the GIFT strain, characterising its mixed origins, and the potential contributions of introgressed regions to selected traits.

Norwich COVID-19 testing initiative pilot: evaluating the feasibility of asymptomatic testing on a university campus.

BACKGROUND: There is a high prevalence of COVID-19 in university-age students, who are returning to campuses. There is little evidence regarding the feasibility of universal, asymptomatic testing to help control outbreaks in this population. This study aimed to pilot mass COVID-19 testing on a university research park, to assess the feasibility and acceptability of scaling up testing to all staff and students. METHODS: This was a cross-sectional feasibility study on a university research park in the East of England. All staff and students (5625) were eligible to participate. All participants were offered four PCR swabs, which they self-administered over two weeks. Outcome measures included uptake, drop-out rate, positivity rates, participant acceptability measures, laboratory processing measures, data collection and management measures. RESULTS: 798 (76%) of 1053 who registered provided at least one swab; 687 (86%) provided all four; 792 (99%) of 798 who submitted at least one swab had all negative results and 6 participants had one inconclusive result. There were no positive results. 458 (57%) of 798 participants responded to a post-testing survey, demonstrating a mean acceptability score of 4.51/5, with five being the most positive. CONCLUSIONS: Repeated self-testing for COVID-19 using PCR is feasible and acceptable to a university population.

Deterioration in renal function associated with fibrate therapy.

BACKGROUND: Fibric acid derivatives (fibrates) are commonly used for the treatment of hyperlipidemia. A side-effect of these medications that is not well recognized is deterioration in renal function during therapy. This study reviewed a series of patients who showed such a deterioration. METHODS: The design was a retrospective chart review. Data extracted included creatinine, urea, cyclosporine levels, medical history, and medications. Charts were examined for other potential reasons for a change in creatinine. RESULTS: There were a total of 10 patients. All were males between the ages of 37 and 71. All had a history of renal insufficiency. Six had received a renal transplant and, of these, 5 were on cyclosporine. Reasons for underlying renal impairment included diabetes, hypertension, nephrosclerosis, and renal disease of unknown etiology. Most patients had risk factors for or the presence of vascular disease. The mean pre-treatment creatinine was 182 +/- 14 micromol/l (2.1 +/- 0.2 mg/dl) (mean +/- SE), compared to a peak creatinine on the medication of 247 +/- 16 micromol/l (2.8 +/- 0.2 mg/dl) (p < 0.001). The post-medication mean was 183 +/- 13 (2.1 +/- 0.1 mg/dl) (p < 0.001 vs maximum creatinine). Urea values also increased with therapy and decreased following discontinuation of the fibrate. Cyclosporine levels did not change with treatment. All recorded creatine kinase values were within the normal range. CONCLUSIONS: A group of 10 men showed a reversible deterioration in renal function while being treated with a fibrate for hyperlipidemia. The mechanism involved in the deterioration in renal function is not clear. The most plausible mechanism is one based on renal hemodynamics, given the rapid and complete reversibility that was noted and the finding that most patients had risk factors for vascular disease. If patients with pre-existing renal dysfunction are to receive a trial of fibrate therapy, this should be done with caution and

Bright stars in the sky?

Actions to improve the health of people in rural and remote areas are supported by people's ability as individuals and as a community to take part actively in the design, management and evaluation of their own health services. To do this successfully, people need information about their health, resources to support their actions and political support or legitimacy. This article focuses on the third requirement. At the beginning of 2000, there seems to be strong political interest in improving the status of rural communities and rural services overall, including rural health and health services. The constellation of events that contribute to this encouraging state of affairs includes the Regional Australia Summit that was held in October 1999, the existence of a strategic framework for rural health that was agreed on by all health jurisdictions (Healthy Horizons), improved clarity about the relative state of health and health service utilisation in rural and remote areas, and the Prime Minister's recent commitment to improve rural services. The next major national opportunity to convert these positive signs into action comes with the Federal Budget in May 2000, the content of which will be closely watched by people concerned about improving health in country areas.

Familial predisposition to breast cancer in a British population: implications for prevention.

The aims of this study were to estimate the familial relative risk of breast cancer according to the age of the at risk individual and the age at which the relative was affected, and to estimate the proportion of the general population in several breast cancer risk categories because of a family history and, thus estimate the potential to reduce the overall breast cancer burden using interventions targeted at women at increased risk because of family history. Familial relative risks were computed by comparing breast cancer incidence in relatives of 2809 breast cancer cases from a population based case series with that expected from general population incidence rates. The proportion of the general population in different categories of risk according to family history was estimated from the relative risk of breast cancer for that category and the proportion of cases in that category. 389 (13.8%) cases had at least 1 first degree relative with breast cancer. The relative risk of breast cancer in sisters of index cases was 1.90 (95% confidence interval (CI) 1.63-2.36) and that in mothers 1.73 (1.52-1. 97). The risk to mothers of cases diagnosed under 50 years of age tended to decrease in older mothers, but no age effect was seen for mothers of cases diagnosed >/=50 years of age. There was no evidence that relative risk to sisters declined with age. For women with 2 affected first degree relatives the relative risk was 2.85 (2.12-3. 76). From these data, we estimate that in the general population 6. 8% of women under the age of 50 years and 9.7% of women aged 50-65 years have at least 1 first degree relative affected with breast cancer. Two per cent of women under 50 years have a family history which confers an increased risk of at least 2.5-fold. An intervention targeted at this group that reduced breast cancer morbidity by 20% would reduce the total burden of breast cancer in this age group by 1.1% at most. A family history of breast cancer is quite common in the general population, but preventive interventions targeted at women at high risk of breast cancer because of family history will have limited impact on breast cancer morbidity as a whole.

No association between a polymorphism in the steroid metabolism gene CYP17 and risk of breast cancer.

A recent study showed an association between a single base substitution, T-->C, in the promotor region of the CYP17 gene, the risk of breast cancer and age at menarche in Asian, African-American and Latino women from California and Hawaii. The C allele was associated with increased risk of breast cancer, significantly so for patients presenting with advanced disease, whereas the TT genotype was associated with later age at menarche in control subjects. We attempted to confirm these findings in a large case-control study in East Anglia, England (835 cases and 591 control subjects). We found no evidence of an increased risk of breast cancer [odds ratio (OR) 1.10, confidence interval (CI) 0.89-1.37] or advanced breast cancer (OR 0.88, CI 0.38-2.01) in C allele carriers, nor any association between age at menarche and genotype. We conclude that these alleles do not significantly alter breast cancer risk in the English population.

How common is medical training in palliative care? A postal survey of general practitioners.

BACKGROUND: General practitioners (GPs) have a central role in palliative care, yet research continues to reveal room for improvement in symptom control at home. There is a need to evaluate how well-prepared GPs are for this task of caring for the dying at home. AIM: To evaluate the training in palliative care GPs have received throughout their careers. METHOD: Postal survey of 450 randomly selected East Anglian GP principals, investigating training in five areas of palliative care (pain control, control of other symptoms, communication skills, bereavement care, use of syringe driver), as clinical students, junior hospital doctors, GP trainees (registrars), and GP principals. RESULTS: A response rate of 86.7% was obtained. While GPs were clinical students, training was uncommon, (32% reported no training in pain control, and 58% no training in bereavement care), although there has been a significant increase in more recent years. Training as junior doctors was particularly uncommon (over 70% report no training in communication skills or bereavement care); there was some evidence of an increase in more recent years. During the GP trainee year, training was much more common. For GP principals, most areas had been covered, although over 20% reported no training in communication skills and bereavement care. During the community-based years as trainee and principal, training was significantly more common than during the hospital-based years of training as clinical student and junior doctor. CONCLUSIONS: There is a continuing need for medical education in palliative care. Particular attention should be paid to the basic medical education of clinical students and the training of junior doctors, especially regarding communication skills and bereavement care.

Adolescent milk, dairy product and fruit consumption and testicular cancer.

There is an association between dairy product consumption and the incidence of testicular cancer in different countries. To test the hypothesis that milk and dairy products are risk factors, a case-control study was performed in East Anglia, UK. All the cases were men with testicular cancer and for each of the 200 cases there were four controls, two cancer controls and two population controls. The response rate of those eligible subjects who received a questionnaire was: cases 73%, cancer controls 65% and population controls 57%. All responding subjects completed a dietary questionnaire including questions on current and adolescent milk, dairy product and fruit and vegetable consumption. The answers were corroborated when possible by the subjects' mothers using a separate questionnaire. Cases consumed significantly more milk in adolescence than population controls, but this difference did not apply to other dairy products or fruit. The consumption of milk by cancer controls was intermediate between cases and population controls. Cancer controls with non-epithelial cancers had a milk consumption similar to cases, whereas subjects with epithelial cancers had a consumption similar to population controls. In a multivariate analysis the odds ratio between cases and population controls for the association of undescended testis and testicular cancer was 7.19 (95% CI 2.36-21.9) and for each extra quarter pint of milk consumed it was 1.39 (95% CI 1.19-1.63).

Transplantation of human endothelial cell monolayer on artificial vascular prosthesis: the effect of growth-support surface chemistry, cell seeding density, ECM protein coating, and growth factors.

The failure rates of synthetic vascular grafts, when placed in low blood flow environments in humans, are not acceptable. Thus, endothelial cell (EC) seeding technology of vascular grafts was developed to prepare prostheses lined with a human monolayer expressing optimal thromboresistant properties. In a clinical setting, endothelialization of a graft can be achieved using higher cell seeding densities, or by creating a surface on which EC can adhere and grow to confluence. But, human endothelial cells show little or no proliferation on the currently available graft materials. In this study, surface modification of PTFE and ePTFE by ammonia plasma treatment was carried out to enhance its interactions with ECM protein, EC growth factors, and with EC harvested from human umbilical vein (HUVEC), and from human saphenous veins (HSVEC). Our data shows that various vascular graft materials generated from ammonia plasma treated PTFE and ePTFE exhibited statistically significant improvements in HUVEC and HSVEC growth when compared to their respective controls (p values < 0.001). Growth of HSVEC on ammonia plasma treated ePTFE without ECM protein coating was also found to be statistically significant in comparison to that on fibronectin coated ePTFE (p < 0.001). The final HSVEC cell densities found on various ePTFE surfaces prepared from ammonia plasma treated ePTFE, suggests that transplantation of HSVEC monolayers on vascular prostheses can be established within clinically relevant times. Ammonia plasma treatment process provides an unique opportunity to surface modify prosthetic materials of various construct to transplant mammalian cells including those that have undergone ex vivo gene transfer, and to deliver angiogenic molecules to a target area for tissue development.

Rates of admission to hospital for asthma.

OBJECTIVE: To describe trends in hospital admission rates for asthma in England and Wales (1976-85), the East Anglian region (from 1976 to 1991-2), and Wales (1980-90). DESIGN: Descriptive study. SETTING: Hospitals in England and Wales; hospitals in the East Anglian Regional Health Authority; hospitals in Wales. MAIN OUTCOME MEASURES: Hospital admissions for asthma as principal diagnosis in England and Wales (Hospital In-patient Enquiry, 1976-85), for the East Anglian region (Hospital In-patient Enquiry, 1976-7; Hospital Activity Analysis, 1978-86; Regional Information System, 1987-8 to 1991-2), and for Wales (Hospital Activity Analysis, 1980-90). RESULTS: Rates for England and Wales as a whole showed a steady upward trend throughout the period examined. Rates in East Anglia, though they were similar to the national trends in the early years, showed a peak in 1985 (for males and females) with some indication of a decline in rates thereafter. Rates for Wales showed an upward trend until 1988 (for both males and females) after which they showed a decline. CONCLUSIONS: Interpretation of the East Anglian trends is made more difficult by the change in England in 1987 of the system for the collection of hospital admission data. The fact that the rates for the East Anglian region seem to decline before this change and other considerations suggest that the observed trends, although partly reflecting the disruption of the coding during the changeover in systems, may not be entirely artefactual. The possible roles of diagnostic transfer and changes in the delivery of care, asthma treatment, admission and readmission policies, and the severity and prevalence of asthma in changing admission rates are considered. The changing trends in admission rates for East Anglia and Wales reflect recently published trends for mortality from asthma in England.