Echocardiographic assessment of left ventricular structure and function in hypertensive disorders of pregnancy at six months and two years postpartum

Purpose

Hypertensive disorders of pregnancy (HDP) are associated with longer term postpartum cardiovascular sequelae, including double the risk of ischaemic heart disease and cardiovascular mortality (1).

Transthoracic echocardiograms (TTE) were performed in women with pregnancies complicated by gestational hypertension and pre-eclampsia, or uncomplicated pregnancy, at six months and two years postpartum. The aim was to longitudinally assess cardiac structure and function in women with HDP and compare this to women who had a normotensive pregnancy. The six-month results have been previously reported, we now present the two-year data.

Methods

A prospective cohort study was conducted in a pre-specified subgroup of 126 patients within a single, tertiary referral centre as part of the P4 (Post Partum, Physiology, Psychology, and Paediatric Follow Up) study (2). 74 (59%) women had a normotensive pregnancy, and 52 (41%) had a pregnancy complicated by HDP.

Women with pre-existing hypertension were excluded from the study. The mean patient age at time of six-month postpartum TTE was 32 years (range 22–47 years). TTEs were performed by blinded experienced sonographers and reported by a single blinded imaging cardiologist.

Results

Six months postpartum. 126 women underwent TTE at six months postpartum. Although all results fell within normal ranges, compared to women with a normotensive pregnancy, those with HDP had increased left ventricle (LV) wall thickness, higher relative wall thickness, and increased LV mass. E/A ratio was lower, and E/E' ratios higher in the group with pregnancy complicated by HDP, indicating a trend towards poorer diastolic function (2,3).

Two years postpartum. 35 women completed a two year postpartum TTE (18 normotensive, 17 HDP). Measurements fell within normal ranges in both groups of women.

At two years postpartum, women with HDP had larger BSA (1.9 vs 1.71 m2 p=0.003), larger LV internal diastolic diameter (48.4 vs 45.5mm p=0.017) and increased inter-ventricular septum thickness (8.5 vs 7.7mm p=0.007) compared to those with normotensive pregnancy. LV mass was greater in women with HDP (98.1 vs 81.5g), as was LA volume indexed (25.4 vs 23.4 cm3/m3), however these differences did not reach significance (p=0.053 and 0.196 respectively). Compared to normotensive women, those with HDP had higher septal (8.7 vs 7.3 p=0.014) and lateral (6.6 vs 5.4 p=0.017) E/E' ratios, indicating a trend towards diastolic dysfunction.

Conclusion

Despite measurements falling within normal ranges, our results indicate that women with HDP have changes in cardiac structure and function that persist out to two years postpartum. Limitations exist due to incomplete follow up, leading to small sample size; this was partially due to restrictions on service provision in the context of the COVID-19 pandemic.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): The St George and Sutherland Research Foundation.Philanthropic donation from Emeritus Professor Richard Henry.

Distinctive gut microbiomes of ankylosing spondylitis and inflammatory bowel disease patients suggest differing roles in pathogenesis and correlate with disease activity

BACKGROUND

Multiple studies have confirmed dysbiosis in ankylosing spondylitis (AS) and inflammatory bowel disease (IBD); however, due to methodological differences across studies, it has not been possible to determine if these diseases have similar or different gut microbiomes.

RESULTS

In this study, faecal and intestinal biopsies were obtained from 33 Australian AS patients (including 5 with concomitant IBD, 'AS-IBD'), 59 IBD patients and 105 healthy controls. Stool samples were also obtained from 16 Italian AS patients and 136 Swedish AS patients. Focusing on the Australian cohort, AS, AS-IBD and IBD patients differed from one another and from healthy controls in both alpha and beta diversity. AS patients with and without clinical IBD could be distinguished from one another with moderate accuracy using stool microbiome (AUC=0.754). Stool microbiome also accurately distinguished IBD patients from healthy controls (AUC=0.757). Microbiome composition was correlated with disease activity measured by BASDAI and faecal calprotectin (FCP) levels. Enrichment of potentially pathogenic Streptococcus was noted in AS, AS-IBD and IBD patients. Furthermore, enrichment of another potentially pathogenic genus, Haemophilus, was observed in AS, AS-IBD, IBD, AS patients with increased BASDAI, and IBD patients with faecal calprotectin >100 μg/mg. Apart from these genera, no other taxa were shared between AS and IBD patients.

CONCLUSIONS

In conclusion, the distinct gut microbiome of AS and AS-IBD patients compared to IBD patients and healthy controls is consistent with immunological and genetic evidence suggesting that the gut plays a different role in driving AS compared with IBD. However, enrichment of two potentially pathogenic genera in both diseases suggests that the presence of a shared/common microbial trigger of disease cannot be discounted.

The P4 study: Subsequent pregnancy maternal physiology after hypertensive and normotensive pregnancies

OBJECTIVES

Hypertensive disorders of pregnancy are associated with subsequent increased risk of cardiometabolic disease. Adverse cardiometabolic measures are noted soon after hypertensive versus normotensive pregnancy (NP); to what degree these persist into a subsequent pregnancy (SP) is unknown. This study aimed to assess women's physiology early in SP after hypertensive pregnancy (HP: preeclampsia or gestational hypertension) or NP and compare SP to 6 months postpartum findings from the index pregnancy.

STUDY DESIGN

Prospective sub-study of the P4 (Postpartum, Physiology, Psychology and Paediatric) observational cohort. Measurements six months after NP versus HP, and the SP at 11-13 weeks gestation.

MAIN OUTCOME MEASURES

Blood pressure (BP), blood and urine tests (urine ACR, HOMA-IR, LDL cholesterol), body composition, and contribution of maternal characteristics and inter-pregnancy factors to BP and body fat (FM%) in SP.

RESULTS

49 women (34 NP, 15 HP). In the SP, post-HP women had higher BP (112/70 mmHg HP vs 102/64 mmHg NP; p < .001), with no significant drop from six months postpartum to early SP. On regression analysis, systolic and diastolic BP at 6-months were the major predictors for SP systolic (p < 0.001) and diastolic (p = 0.009) BP respectively in the SP. Longer interpregnancy interval and increased FM% 6-months postpartum were associated with higher SP FM% (p < 0.001).

CONCLUSIONS

BP and body fat six months postpartum were similar early in the SP for HP group, and postpartum BP and FM% were major predictors of their corresponding SP measurements. Postpartum/inter-pregnancy intervention programs to improve these cardiometabolic risk markers might help improve women's long-term health and require investigation.

Distinct chromatin modifications at the Il33 locus in mast cells contribute to sex dimorphic susceptibility to EAE, an autoimmune CNS demyelinating disease

Many autoimmune diseases, including multiple sclerosis (MS), exhibit a striking female bias, but the underlying mechanisms remain poorly understood. Using the SJL mouse model of MS, experimental autoimmune encephalomyelitis (EAE), which recapitulates this sex dimorphism, we previously demonstrated that preferential IL-33 expression contributes to male protection. IL-33 expression by mast cells in PLP139–151-immunized males activates type 2 innate lymphoid cells, which in turn drives a non-pathogenic Th2 response to myelin peptide. Testosterone directly activates Il33 in male but not female mast cells, but this male-specific response is also observed with other modes of activation, suggesting there are constraints on the chromatin landscape that limit Il33 expression in females. Here we use chromatin immunoprecipitation (ChIP) and ATAC-seq to examine chromatin modifications at the Il33 locus. At steady state, ChIP assays reveal activating H3K4me3 and H3K9ac histone modifications at the promoter and conserved non-coding sequences within the Il33 gene are most prevalent in male-derived cells, while H3K27me3 repressive marks dominate in females. Increased basal Il33 chromatin accessibility assessed by ATAC-seq is also evident in males. Together, these results indicate that while testosterone can directly stimulate IL-33 production, it also exerts effects on Il33 during development conferring a higher potential for expression in males by altering the chromatin landscape. RNAseq analyses of IgE-activated mast cells revealed a broad range of sex-biased gene expression, indicating that sex hormone influences during development drive epigenetic changes and may be a common mechanism to explain sex dimorphism in immunity.

Distinct chromatin modifications at the Il33 locus in mast cells contribute to sex dimorphic susceptibility to EAE, an autoimmune CNS demyelinating disease

Many autoimmune diseases, including multiple sclerosis (MS) exhibit a striking female bias, but the underlying mechanisms remain poorly understood. Using the SJL mouse model of MS, experimental autoimmune encephalomyelitis (EAE), which recapitulates this sex dimorphism, we previously demonstrated that preferential IL-33 expression contributes to male protection. IL-33 expression by mast cells in PLP139–151-immunized males activates type 2 innate lymphoid cells, which in turn drives a non-pathogenic Th2 response to myelin peptide. Testosterone directly activates Il33 in male but not female mast cells, but this male-specific response is also maintained with other modes of activation, including FcɛR1-crosslinking, suggesting there are constraints on the chromatin landscape that limit Il33 expression in females. Here we use ChIP and ATAC-seq to show that the dynamics of chromatin modifications at the Il33 locus is sex-dimorphic. At steady state, ChIP assays reveal activating H3K4me3 and H3K9ac histone modifications at the promoter and conserved non-coding sequences within the Il33 gene are most prevalent in male-derived cells, while H3K27me3 repressive marks dominate in females. This pattern is similar in IgE-DNP-activated mast cells. Increased basal Il33 chromatin accessibility assessed by ATAC-seq is evident in males. Together, these results indicate that while testosterone can directly stimulate IL-33 production, it also exerts effects on Il33 during development conferring a higher potential for expression in males.

Comparison of methods to construct a genetic risk score for prediction of rheumatoid arthritis in the population-based Nord-Trøndelag Health Study, Norway

Objectives

To evaluate selection methods among published single-nucleotide polymorphisms (SNPs) associated with RA to construct predictive genetic risk scores (GRSs) in a population-based setting.

Methods

The Nord-Trøndelag Health (HUNT) Study is a prospective cohort study among the whole adult population of northern Trøndelag, Norway. Participants in HUNT2 (1995–1997) and HUNT3 (2006–2008) were included (489 RA cases, 61 584 controls). The initial SNP selection from relevant genome-wide studies included 269 SNPs from 30 studies. Following different selection criteria, SNPs were weighted by published odds ratios. The sum of each person’s carriage of all weighted susceptibility variants was calculated for each GRS.

Results

The best-fitting risk score included 27 SNPs [weighted genetic risk score 27 (wGRS27)] and was identified using P-value selection criterion ≤5 × 10−8, the largest possible SNP selection without high linkage disequilibrium (r2 &lt; 0.8), and lasso regression to select for positive coefficients. In a logistic regression model adjusted for gender, age and ever smoking, wGRS27 was associated with RA [odds ratio 1.86 (95% CI 1.71, 2.04) for each s.d. increase, P &lt; 0.001]. The AUC was 0.76 (95% CI 0.74, 0.78). The positive and negative predictive values were 1.6% and 99.7%, respectively, and the positive predictive value was not improved in sensitivity analyses subselecting participants to illustrate settings with increased RA prevalences. Other schemes selected more SNPs but resulted in GRSs with lower predictive ability.

Conclusion

Constructing a wGRS based on a smaller selection of informative SNPs improved predictive ability. Even with a relatively high AUC, the low PPV illustrates that there was a large overlap in risk variants among RA patients and controls, precluding clinical usefulness.

Genomic characterization of a novel circovirus from a stranded Longman's beaked whale (Indopacetus pacificus)

Tissues from a juvenile Longman's beaked whale that stranded in Hawaii in 2010 were screened for viruses using a Next-Generation Sequencing (NGS) approach. From the NGS data, the full genome (1,849 bp) of a novel beaked whale circovirus (BWCV) was determined. Two open reading frames (ORF) were annotated, including ORF1 that encodes the capsid gene, ORF2 that encodes the replication-associated gene, and a 9-bp conserved nonamer on the apex of the open loop found in all circoviruses. Independent phylogenetic analyses based on amino acid sequence alignments of the two CV proteins supported the BWCV as a member of the genus Circovirus, branching as the sister species to the recently discovered canine circovirus. A sequence identity matrix generated from complete genome alignments revealed the BWCV displays between from 51.1 to 56.7% nucleotide identity to other circoviruses, which is lower than the 80% threshold proposed for species demarcation. Considering the genetic and phylogenetic analyses, we propose the formal species designation of beaked whale circovirus. An endpoint PCR assay targeting the BWCV genome confirmed the presence of the BWCV DNA in every tissue from which DNA was extracted, including spleen, muscle, left ventricle, left adrenal gland, liver, lung, cerebrum, cerebellum, and lymph node. An automated in situ hybridization assay utilizing RNAscope® technology and targeting the replication-associated gene resulted in labeling of individual cells morphologically resembling mononuclear leukocytes and cells of blood vessels in diaphragm, liver, lymph nodes, lung, pericardium, oral mucosa and tongue, adrenal gland, testis, aorta, intestine, stomach and heart. The clinical or pathologic significance of BWCV is undetermined, as are its host range, prevalence, and pathogenicity in cetaceans of Hawaiian waters and elsewhere.

Whole-exome sequencing for mutation detection in pediatric disorders of insulin secretion: Maturity onset diabetes of the young and congenital hyperinsulinism

BACKGROUND

To assess the utility of whole-exome sequencing (WES) for mutation detection in maturity-onset diabetes of the young (MODY) and congenital hyperinsulinism (CHI). MODY and CHI are the two commonest monogenic disorders of glucose-regulated insulin secretion in childhood, with 13 causative genes known for MODY and 10 causative genes identified for CHI. The large number of potential genes makes comprehensive screening using traditional methods expensive and time-consuming.

METHODS

Ten subjects with MODY and five with CHI with known mutations underwent WES using two different exome capture kits (Nimblegen SeqCap EZ Human v3.0 Exome Enrichment Kit, Nextera Rapid Capture Exome Kit). Analysis was blinded to previously identified mutations, and included assessment for large deletions. The target capture of five exome capture technologies was also analyzed using sequencing data from >2800 unrelated samples.

RESULTS

Four of five MODY mutations were identified using Nimblegen (including a large deletion in HNF1B). Although targeted, one mutation (in INS) had insufficient coverage for detection. Eleven of eleven mutations (six MODY, five CHI) were identified using Nextera Rapid (including the previously missed mutation). On reconciliation, all mutations concorded with previous data and no additional variants in MODY genes were detected. There were marked differences in the performance of the capture technologies.

CONCLUSIONS

WES can be useful for screening for MODY/CHI mutations, detecting both point mutations and large deletions. However, capture technologies require careful selection.

Assessment of the functional impact of germline BRCA1/2 variants located in non-coding regions in families with breast and/or ovarian cancer predisposition

PURPOSE

The molecular mechanism of breast and/or ovarian cancer susceptibility remains unclear in the majority of patients. While germline mutations in the regulatory non-coding regions of BRCA1 and BRCA2 genes have been described, screening has generally been limited to coding regions. The aim of this study was to evaluate the contribution of BRCA1/2 non-coding variants.

METHODS

Four BRCA1/2 non-coding regions were screened using high-resolution melting analysis/Sanger sequencing or next-generation sequencing on DNA extracted from index cases with breast and ovarian cancer predisposition (3926 for BRCA1 and 3910 for BRCA2). The impact of a set of variants on BRCA1/2 gene regulation was evaluated by site-directed mutagenesis, transfection, followed by Luciferase gene reporter assay.

RESULTS

We identified a total of 117 variants and tested twelve BRCA1 and 8 BRCA2 variants mapping to promoter and intronic regions. We highlighted two neighboring BRCA1 promoter variants (c.-130del; c.-125C > T) and one BRCA2 promoter variants (c.-296C > T) inhibiting significantly the promoter activity. In the functional assays, a regulating region within the intron 12 was found with the same enhancing impact as within the intron 2. Furthermore, the variants c.81-3980A > G and c.4186-2022C > T suppress the positive effect of the introns 2 and 12, respectively, on the BRCA1 promoter activity. We also found some variants inducing the promoter activities.

CONCLUSION

In this study, we highlighted some variants among many, modulating negatively the promoter activity of BRCA1 or 2 and thus having a potential impact on the risk of developing cancer. This selection makes it possible to conduct future validation studies on a limited number of variants.

Indications for delivery in pre-eclampsia

OBJECTIVE

Examine the frequency with which the most accepted indicators for delivery in pre-eclampsia are used in a population with predominantly late-onset (birth > 32 weeks) pre-eclampsia (PE).

METHODS

Retrospective cohort study using the St George Public Hospital (SGH) Hypertension in Pregnancy database. Demographic, pregnancy, and outcome details were extracted and verified by comparison with data collection sheets.

RESULTS

From 2001 to 2013, 908 women (970 babies) with PE were included, of which a subgroup of 303 women (33%) had clearly delineated delivery triggers available. This subgroup of women had similar demographic and outcome characteristics to the total PE population. In this group, the most common maternal trigger for delivery apart from gestational age 37+ weeks was difficult to control/severe hypertension (114 cases, 38%) and the most common fetal trigger intrauterine growth restriction (IUGR: 14 cases, 4%). 78 (35%) of term women had no specific delivery trigger other than gestation. A primary maternal trigger and/or associated complication was slightly more common in those delivering <37 weeks vs 37+ weeks (52 vs 38%, p = .03), while a fetal or combined maternal/fetal complication was over four times more common in preterm women (25 vs 6%, p < .001).

CONCLUSION

In our population of predominantly late-onset PE, maternal triggers for delivery (predominantly severe hypertension) far outweigh fetal triggers (predominantly IUGR). Fetal and mixed indicators for delivery were relatively more common in women delivering preterm, possibly reflecting the severity of placental dysfunction in this subgroup.

Effects of tail docking on the expression of genes related to lipid metabolism in Lanzhou fat-tailed sheep

To evaluate stearoyl-CoA desaturase (SCD), hormone-sensitive lipase (HSL), lipoprotein lipase (LPL), and peroxisome proliferator-activated receptor (PPARγ) expression in Lanzhou fat-tailed sheep (with and without docked tails), 18 rams were randomly divided into two equal groups (docked group, LT; control group, LC). These data were also used to increase the understanding of sheep fat deposition and metabolism. All animals were harvested at the age of 18 months, and expression was determined for 10 tissues. The results indicated that the fat weight of each tissue in LT was higher than in LC (P < 0.05). SCD expression in semitendinosus, omentum majus fat (OF), subcutaneous fat, kidney fat (KF), and subcutaneous rump fat was higher in LT than in LC rams (P < 0.05). Trends (P < 0.10) associated with higher HSL expression of LC in comparison to that of LT rams in intestinal fat, OF, and KF tissues were detected. Numerically, LPL expression was the highest in KF, OF, and kidney tissues, but there were few differences (P > 0.10). PPARγexpression was greater in LT than in LC rams in liver tissues (P < 0.05), but there were few differences in other tissues. No significant differences were found with regard to the regression analysis of expression and adipose tissue weights, but the two indices exhibited the same trend. The results indicated that changes in fatty deposits may be due to the common control of docking management and the minor effects associated with the regulation of SCD, HSL, LPL, and PPARγexpression.

Photoelectron spectrometer for attosecond spectroscopy of liquids and gases

A new apparatus for attosecond time-resolved photoelectron spectroscopy of liquids and gases is described. It combines a liquid microjet source with a magnetic-bottle photoelectron spectrometer and an actively stabilized attosecond beamline. The photoelectron spectrometer permits venting and pumping of the interaction chamber without affecting the low pressure in the flight tube. This pressure separation has been realized through a sliding skimmer plate, which effectively seals the flight tube in its closed position and functions as a differential pumping stage in its open position. A high-harmonic photon spectrometer, attached to the photoelectron spectrometer, exit port is used to acquire photon spectra for calibration purposes. Attosecond pulse trains have been used to record photoelectron spectra of noble gases, water in the gas and liquid states as well as solvated species. RABBIT scans demonstrate the attosecond resolution of this setup.

Carcass parameters and meat quality in meat-goat kids finished on chicory, birdsfoot trefoil, or red clover pastures

This study was conducted during the 2009 and 2010 grazing seasons to assess carcass parameters and chevon (goat meat) quality when meat-goat kids (n=72) were finished on pastures of red clover (Trifolium pratense L.; RCL), birdsfoot trefoil (Lotus corniculatus L.; BFT), or chicory (Cichorium intybus L.; CHIC). Final live weight (P<0.05) and carcass weight (P=0.10) were greater when goats were finished on RCL compared to CHIC with BFT being intermediate. Ribeye area, backfat thickness, body wall thickness, internal fat score, and leg score were not different (P>0.10) among treatments when adjusted for the covariate of carcass weight. Finishing meat-goat kids on RCL, BFT, or CHIC impacted concentrations of fatty acids (FAs) 18:1 trans-10, 18:1 cis-11, 18:2, 18:3 polyunsaturated fatty acids (PUFAs), omega-6, omega-3, and PUFA:saturated fatty acid ratio in longissimus lumborum samples. Finishing meat-goat kids on CHIC, RCL, or BFT pastures produced carcass weights acceptable for most ethnic markets in the USA.

Relationships of milk yield and quality from six breed groups of beef cows to preweaning average daily gain of their calves

Milk yield and quality influence calf preweaning growth and ultimately the sale value of the calf at weaning. This study was conducted to evaluate the relationships of milk production and quality of beef cows to calf preweaning ADG in beef cows sired by Bonsmara, Brangus, Charolais, Gelbvieh, Hereford, and Romosinuano and from Brangus dams to determine whether the relationships were homogeneous across cow breed group. Approximately 50 cows/yr were milked monthly for 6 mo in each of the 7 yr of this study. Milk traits were included in models as linear and quadratic covariates along with interactions of the covariates with sire breed. Tests for curvilinearity and homogeneity of regression coefficients indicated the relationship of calf preweaning ADG to milk yield and quality was quadratic and homogeneous across Charolais and Gelbvieh; linear and homogeneous across Bonsmara, Brangus, and Romosinuano; and linear and different from other sire breeds in Herefords (P < 0.05). Exceptions to this were in the regression of calf preweaning ADG on the natural logarithm of somatic cell count (SCC) and milk urea nitrogen (MUN). The relationship of calf preweaning ADG to SCC was quadratic in Brangus (P < 0.05) and linear in Gelbvieh (P < 0.05) with little evidence (P > 0.05) of a relationship in Bonsmara, Charolais, Hereford, or Romosinuano. There was little evidence (P > 0.05) of a relationship of calf preweaning ADG to MUN in any of the sire breed groups. Results from this study confirmed the importance of the influence of milk yield and quality on calf preweaning growth but indicated this influence can depend on the breed composition of the cow. Furthermore, results suggest that breed origin or adaptation may have influenced the relationships of calf preweaning ADG to cow milk yield and quality.

Disease-associated polymorphisms in ERAP1 do not alter endoplasmic reticulum stress in patients with ankylosing spondylitis

The mechanism by which human leukocyte antigen B27 (HLA-B27) contributes to ankylosing spondylitis (AS) remains unclear. Genetic studies demonstrate that association with and interaction between polymorphisms of endoplasmic reticulum aminopeptidase 1 (ERAP1) and HLA-B27 influence the risk of AS. It has been hypothesised that ERAP1-mediated HLA-B27 misfolding increases endoplasmic reticulum (ER) stress, driving an interleukin (IL) 23-dependent, pro-inflammatory immune response. We tested the hypothesis that AS-risk ERAP1 variants increase ER-stress and concomitant pro-inflammatory cytokine production in HLA-B27(+) but not HLA-B27(-) AS patients or controls. Forty-nine AS cases and 22 healthy controls were grouped according to HLA-B27 status and AS-associated ERAP1 rs30187 genotypes: HLA-B27(+)ERAP1(risk), HLA-B27(+)ERAP1(protective), HLA-B27(-)ERAP1(risk) and HLA-B27(-)ERAP1(protective). Expression levels of ER-stress markers GRP78 (8 kDa glucose-regulated protein), CHOP (C/EBP-homologous protein) and inflammatory cytokines were determined in peripheral blood mononuclear cell and ileal biopsies. We found no differences in ER-stress gene expression between HLA-B27(+) and HLA-B27(-) cases or healthy controls, or between cases or controls stratified by carriage of ERAP1 risk or protective alleles in the presence or absence of HLA-B27. No differences were observed between expression of IL17A or TNF (tumour necrosis factor) in HLA-B27(+)ERAP1(risk), HLA-B27(+)ERAP1(protective) and HLA-B27(-)ERAP1(protective) cases. These data demonstrate that aberrant ERAP1 activity and HLA-B27 carriage does not alter ER-stress levels in AS, suggesting that ERAP1 and HLA-B27 may influence disease susceptibility through other mechanisms.

Ankylosing spondylitis is associated with the anthrax toxin receptor 2 gene (ANTXR2)

OBJECTIVES

ANTXR2 variants have been associated with ankylosing spondylitis (AS) in two previous genome-wide association studies (GWAS) (p∼9×10(-8)). However, a genome-wide significant association (p<5×10(-8)) was not observed. We conducted a more comprehensive analysis of ANTXR2 in an independent UK sample to confirm and refine this association.

METHODS

A replication study was carried out with 2978 cases and 8365 controls. Then, these were combined with non-overlapping samples from the two previous GWAS in a meta-analysis. Human leukocyte antigen (HLA)-B27 stratification was also performed to test for ANTXR2-HLA-B27 interaction.

RESULTS

Out of nine single nucleotide polymorphisms (SNP) in the study, five SNPs were nominally associated (p<0.05) with AS in the replication dataset. In the meta-analysis, eight SNPs showed evidence of association, the strongest being with rs12504282 (OR=0.88, p=6.7×10(-9)). Seven of these SNPs showed evidence for association in the HLA-B27-positive subgroup, but none was associated with HLA-B27-negative AS. However, no statistically significant interaction was detected between HLA-B27 and ANTXR2 variants.

CONCLUSIONS

ANTXR2 variants are clearly associated with AS. The top SNPs from two previous GWAS (rs4333130 and rs4389526) and this study (rs12504282) are in strong linkage disequilibrium (r(2)≥0.76). All are located near a putative regulatory region. Further studies are required to clarify the role played by these ANTXR2 variants in AS.

COL1A1 C-propeptide cleavage site mutation causes high bone mass, bone fragility and jaw lesions: a new cause of gnathodiaphyseal dysplasia?

Gnathodiaphyseal dysplasia (GDD) is a rare autosomal dominant condition characterized by bone fragility, irregular bone mineral density (BMD) and fibro-osseous lesions in the skull and jaw. Mutations in Anoctamin-5 (ANO5) have been identified in some cases. We aimed to identify the causative mutation in a family with features of GDD but no mutation in ANO5, using whole exome capture and massive parallel sequencing (WES). WES of two affected individuals (a mother and son) and the mother's unaffected parents identified a mutation in the C-propeptide cleavage site of COL1A1. Similar mutations have been reported in individuals with osteogenesis imperfecta (OI) and paradoxically increased BMD. C-propeptide cleavage site mutations in COL1A1 may not only cause 'high bone mass OI', but also the clinical features of GDD, specifically irregular sclerotic BMD and fibro-osseous lesions in the skull and jaw. GDD patients negative for ANO5 mutations should be assessed for mutations in type I collagen C-propeptide cleavage sites.

Association study of genes related to bone formation and resorption and the extent of radiographic change in ankylosing spondylitis

OBJECTIVE

To identify genetic associations with severity of radiographic damage in ankylosing spondylitis (AS).

METHOD

We studied 1537 AS cases of European descent; all fulfilled the modified New York Criteria. Radiographic severity was assessed from digitised lateral radiographs of the cervical and lumbar spine using the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS). A two-phase genotyping design was used. In phase 1, 498 single nucleotide polymorphisms (SNPs) were genotyped in 688 cases; these were selected to capture >90% of the common haplotypic variation in the exons, exon-intron boundaries, and 5 kb flanking DNA in the 5' and 3' UTR of 74 genes involved in anabolic or catabolic bone pathways. In phase 2, 15 SNPs exhibiting p<0.05 were genotyped in a further cohort of 830 AS cases; results were analysed both separately and in combination with the discovery phase data. Association was tested by contingency tables after separating the samples into 'mild' and 'severe' groups, defined as the bottom and top 40% by mSASSS, adjusted for gender and disease duration.

RESULTS

Experiment-wise association was observed with the SNP rs8092336 (combined OR 0.32, p=1.2×10(-5)), which lies within RANK (receptor activator of NFκB), a gene involved in osteoclastogenesis, and in the interaction between T cells and dendritic cells. Association was also found with the SNP rs1236913 in PTGS1 (prostaglandin-endoperoxide synthase 1, cyclooxygenase 1), giving an OR of 0.53 (p=2.6×10(-3)). There was no observed association between radiographic severity and HLA-B*27.

CONCLUSIONS

These findings support roles for bone resorption and prostaglandins pathways in the osteoproliferative changes in AS.

Combined sulfur K-edge XANES-EXAFS study of the effect of protonation on the sulfate tetrahedron in solids and solutions

Sulfur K-edge X-ray absorption spectroscopy (XAS) has been used to distinguish between aqueous and solid sulfates and to investigate changes in their speciation. Data have been collected for tetrahedrally coordinated S in K2SO4 and KHSO4 solids and aqueous solutions. With a first qualitative analysis of the X-ray absorption near-edge structure (XANES) spectra, it has been observed that those for solids are much more structured and distinguishable from those of aqueous solutions. The protonation state has a strong effect on the white line of sulfates and has been assigned to the different charge delocalization in the samples, the effect of the solvating water molecules and multiple scattering effects. In the extended X-ray absorption fine structure (EXAFS) spectra, the backscattering from the first O shell dominated the EXAFS fine structure function, χ(k), but the nonlinear multiple scattering contributions occurring in the first coordination shell are significant and must be considered in the EXAFS analysis. The intensity of these contributions strongly depend on the symmetry of the system. For a distorted tetrahedron, the intensity of the multiple scattering contributions is less than that found in a regular tetrahedron. The FEFF code has been used to model the contributions of the multiple-scattering processes. The observed experimental evidence in the XAS data can be used to distinguish between sulfates in solids and liquids. This is applicable to many chemical, geochemical, and biological systems.

Fatty acid composition differences between adipose depot sites in dairy and beef steer breeds

The objective of the study was to compare fatty acid composition of longissimus dorsi (LD) and kidney fat (KF) in Holstein steers (HS), Simmental steers (SS) and Chinese LongDong Yellow Cattle steers (CLD). All steers received the same nutrition and management but in different locations. Cattle were harvested at approximately 550 kg and fatty acid composition of longissimus dorsi and kidney fat was analyzed in samples taken after 3 days of aging. There was evidence (P < 0.05) that C18:3n6 was greater in KF than LD in CLD cattle but not in HS or SS cattle. Percentage C18:1n9, C18:2n6, C18:3n3, and n6 fatty acids were greater in LD than KF for all breeds (P < 0.05), but the difference between fat sources for n6 in CLD cattle was smaller than the other two breeds. The LD had greater percentage of polyunsaturated fatty acids (PUFA), monounsaturated fatty acids (MUFA), and a greater ratio of n6:n3 PUFAs compared to the KF in each breed (P < 0.05). The △(9)-desaturase catalytic activity index was greater in LD than in KF in each breed group (P < 0.05). Percentage cis-9, trans-11 CLA was greater in KF than LD in HS (P < 0.05) but not SS or CLD cattle. These results indicate fatty acid percentages generally differed between longissimus dorsi fat and kidney fat. Further, there was some indication that some of these differences between fatty acid deposition sites were not consistent across breed group.

High-resolution SNP microarray investigation of copy number variations on chromosome 18 in a control cohort

Copy number variations (CNVs) as described in the healthy population are purported to contribute significantly to genetic heterogeneity. Recent studies have described CNVs using lymphoblastoid cell lines or by application of specifically developed algorithms to interrogate previously described data. However, the full extent of CNVs remains unclear. Using high-density SNP array, we have undertaken a comprehensive investigation of chromosome 18 for CNV discovery and characterisation of distribution and association with chromosome architecture. We identified 399 CNVs, of which loss represents 98%, 58% are less than 2.5 kb in size and 71% are intergenic. Intronic deletions account for the majority of copy number changes with gene involvement. Furthermore, one-third of CNVs do not have putative breakpoints within repetitive sequences. We conclude that replicative processes, mediated either by repetitive elements or microhomology, account for the majority of CNVs in the healthy population. Genomic instability involving the formation of a non-B structure is demonstrated in one region.

Characteristics of hypertensive disorders in twin versus singleton pregnancies

OBJECTIVE

To determine the characteristics of hypertensive disorders of pregnancy in twin compared with singleton pregnancies.

STUDY DESIGN

Analysis of a prospectively recorded database of 4976 hypertensive pregnancies.

MAIN OUTCOME MEASURES

Comparison of progression to pre-eclampsia and maternal and neonatal outcomes.

RESULTS

There were 3942 singleton and 214 twin pregnancies. De novo hypertension in twin pregnancy was diagnosed earlier (p<0.001). In singleton pregnancies with de novo hypertension (n=3161), 60% had an initial diagnosis of gestational hypertension (GH) and 40% had pre-eclampsia (PE). In twin pregnancies with de novo hypertension (n=199), 35% of women were initially diagnosed with GH and 65% with PE (p<0.001). At delivery, 46% of the singletons had GH and 54% had PE, compared with twin pregnancies where 23% had GH and 77 % had PE (p<0.001). The progression from GH to PE for twins was twice that of singleton pregnancies (p<0.001). There were 781 singleton and 15 twin pregnancies with chronic hypertension (CH). Twin pregnancies complicated by CH were more likely to progress to PE than singletons (p<0.01). The gestation at delivery was earlier for twin pregnancies (p<0.001) and there were more twins that were smaller for gestational age (p<0.001). There were no differences in maternal outcomes.

CONCLUSION

Women carrying twins with de novo hypertension are more likely to present earlier, have initial PE and to subsequently progress from GH to PE. Neonatal outcomes are worse in such pregnancies.

A new species of Isospora (Apicomplexa: Eimeriidae) from the greenfinch Carduelis chloris (Passeriformes: Fringillidae)

A new species of isosporan (Apicomplexa: Eimeriidae) is reported from the greenfinch, Carduelis chloris (Passeriformes: Fringillidae), in England. Oocysts of Isospora daszaki n.sp. are spherical to subspherical, 18.8 × 20.3 (16.8-22.4 × 16.8-25.2) μm, with a shape index (length/width) of 1.08 (1.07-1.1). Micropyle, polar granules and oocyst residuum are absent. Sporocysts are 9.4 × 14.8 (8.4-11.2 × 12.6-18.2) μm, a shape index of 1.6, with Stieda and substieda bodies. Gamogony was seen in the ileum, and merozoites were present in blood lymphocytes.

Genome-wide association study to identify genetic determinants of severe asthma

BACKGROUND

The genetic basis for developing asthma has been extensively studied. However, association studies to date have mostly focused on mild to moderate disease and genetic risk factors for severe asthma remain unclear.

OBJECTIVE

To identify common genetic variants affecting susceptibility to severe asthma.

METHODS

A genome-wide association study was undertaken in 933 European ancestry individuals with severe asthma based on Global Initiative for Asthma (GINA) criteria 3 or above and 3346 clean controls. After standard quality control measures, the association of 480 889 genotyped single nucleotide polymorphisms (SNPs) was tested. To improve the resolution of the association signals identified, non-genotyped SNPs were imputed in these regions using a dense reference panel of SNP genotypes from the 1000 Genomes Project. Then replication of SNPs of interest was undertaken in a further 231 cases and 1345 controls and a meta-analysis was performed to combine the results across studies.

RESULTS

An association was confirmed in subjects with severe asthma of loci previously identified for association with mild to moderate asthma. The strongest evidence was seen for the ORMDL3/GSDMB locus on chromosome 17q12-21 (rs4794820, p=1.03×10((-8)) following meta-analysis) meeting genome-wide significance. Strong evidence was also found for the IL1RL1/IL18R1 locus on 2q12 (rs9807989, p=5.59×10((-8)) following meta-analysis) just below this threshold. No novel loci for susceptibility to severe asthma met strict criteria for genome-wide significance.

CONCLUSIONS

The largest genome-wide association study of severe asthma to date was carried out and strong evidence found for the association of two previously identified asthma susceptibility loci in patients with severe disease. A number of novel regions with suggestive evidence were also identified warranting further study.

Plasma uric acid remains a marker of poor outcome in hypertensive pregnancy: a retrospective cohort study

OBJECTIVE

To examine the relationship between hyperuricaemia, haemoconcentration and maternal and fetal outcomes in hypertensive pregnancies.

DESIGN

Retrospective analysis of a database of hypertensive pregnancies.

SETTING

St George Hospital, a major obstetric unit in Australia.

POPULATION

A cohort of 1880 pregnant women without underlying hypertension or renal disease, referred for management of pre-eclampsia or gestational hypertension.

METHODS

Demographic, clinical and biochemical data at time of referral and delivery were collected for each pregnancy. Women were grouped according to diagnosis (pre-eclampsia or gestational hypertension) and logistic regression analysis was used to determine the relationship between uric acid, haemoglobin, haematocrit and adverse outcomes; an α level of P < 0.01 was used for statistical significance.

MAIN OUTCOME MEASURES

Composites of adverse maternal and fetal outcomes.

RESULTS

In women with 'benign' GH (without proteinuria or any other maternal clinical feature of pre-eclampsia) gestation-corrected hyperuricaemia was associated with increased risk of a small-for-gestational-age infant (OR 2.5; 95% CI 1.3-4.8) and prematurity (OR 3.2; 95% CI 1.4-7.2), but not with adverse maternal outcome. In the whole cohort of hypertensive pregnant women (those with pre-eclampsia or gestational hypertension) the risk of adverse maternal outcome (OR 2.0; 95% CI 1.6-2.4) and adverse fetal outcome (OR 1.8; 95% CI 1.5-2.1) increased with increasing concentration of uric acid. Hyperuricaemia corrected for gestation provided additional strength to these associations. Haemoglobin and haematocrit were not associated with adverse pregnancy outcome.

CONCLUSIONS

Hyperuricaemia in hypertensive pregnancy remains an important finding because it identifies women at increased risk of adverse maternal and particularly fetal outcome; the latter, even in women with gestational hypertension without any other feature of pre-eclampsia.

'Sink or swim': an evaluation of the clinical characteristics of individuals with high bone mass

SUMMARY

High bone mineral density on routine dual energy X-ray absorptiometry (DXA) may indicate an underlying skeletal dysplasia. Two hundred fifty-eight individuals with unexplained high bone mass (HBM), 236 relatives (41% with HBM) and 58 spouses were studied. Cases could not float, had mandible enlargement, extra bone, broad frames, larger shoe sizes and increased body mass index (BMI). HBM cases may harbour an underlying genetic disorder.

INTRODUCTION

High bone mineral density is a sporadic incidental finding on routine DXA scanning of apparently asymptomatic individuals. Such individuals may have an underlying skeletal dysplasia, as seen in LRP5 mutations. We aimed to characterize unexplained HBM and determine the potential for an underlying skeletal dysplasia.

METHODS

Two hundred fifty-eight individuals with unexplained HBM (defined as L1 Z-score ≥ +3.2 plus total hip Z-score ≥ +1.2, or total hip Z-score ≥ +3.2) were recruited from 15 UK centres, by screening 335,115 DXA scans. Unexplained HBM affected 0.181% of DXA scans. Next 236 relatives were recruited of whom 94 (41%) had HBM (defined as L1 Z-score + total hip Z-score ≥ +3.2). Fifty-eight spouses were also recruited together with the unaffected relatives as controls. Phenotypes of cases and controls, obtained from clinical assessment, were compared using random-effects linear and logistic regression models, clustered by family, adjusted for confounders, including age and sex.

RESULTS

Individuals with unexplained HBM had an excess of sinking when swimming (7.11 [3.65, 13.84], p < 0.001; adjusted odds ratio with 95% confidence interval shown), mandible enlargement (4.16 [2.34, 7.39], p < 0.001), extra bone at tendon/ligament insertions (2.07 [1.13, 3.78], p = 0.018) and broad frame (3.55 [2.12, 5.95], p < 0.001). HBM cases also had a larger shoe size (mean difference 0.4 [0.1, 0.7] UK sizes, p = 0.009) and increased BMI (mean difference 2.2 [1.3, 3.1] kg/m(2), p < 0.001).

CONCLUSION

Individuals with unexplained HBM have an excess of clinical characteristics associated with skeletal dysplasia and their relatives are commonly affected, suggesting many may harbour an underlying genetic disorder affecting bone mass.

Evidence of genetic association between TNFRSF1A encoding the p55 tumour necrosis factor receptor, and ankylosing spondylitis in UK Caucasians

OBJECTIVES

To replicate the possible genetic association between ankylosing spondylitis (AS) and TNFRSF1A.

METHODS

TNFRSF1A was re-sequenced in 48 individuals with AS to identify novel polymorphisms. Nine single nucleotide polymorphisms (SNPs) in TNFRSF1A and 5 SNPs in the neighbouring gene SCNN1A were genotyped in 1604 UK Caucasian individuals with AS and 1019 matched controls. An extended study was implemented using additional genotype data on 8 of these SNPs from 1400 historical controls from the 1958 British Birth Cohort. A meta-analysis of previously published results was also undertaken.

RESULTS

One novel variant in intron 6 was identified but no new coding variants. No definite associations were seen in the initial study but in the extended study there were weak associations with rs4149576 (p=0.04) and rs4149577 (p=0.007). In the meta-analysis consistent, somewhat stronger associations were seen with rs4149577 (p=0.002) and rs4149578 (p=0.006).

CONCLUSIONS

These studies confirm the weak genetic associations between AS and TNFRSF1A. In view of the previously reported associations of TNFRSF1A with AS, in Caucasians and Chinese, and the biological plausibility of this candidate gene, replication of this finding in well powered studies is clearly indicated.

Risedronate in adults with osteogenesis imperfecta type I: increased bone mineral density and decreased bone turnover, but high fracture rate persists

Bisphosphonates can increase bone mineral density (BMD) in children with osteogenesis imperfecta (OI). In this study of adults with OI type I, risedronate increased BMD at lumbar spine (but not total hip) and decreased bone turnover. However, the fracture rate in these patients remained high.

INTRODUCTION

Intravenous bisphosphonates given to children with OI can increase BMD and reduce fracture incidence. Oral and/or intravenous bisphosphonates may have similar effects in adults with OI. We completed an observational study of the effect of risedronate in adults with OI type I.

METHODS

Thirty-two adults (mean age, 39 years) with OI type I were treated with risedronate (total dose, 35 mg weekly) for 24 months. Primary outcome measures were BMD changes at lumbar spine (LS) and total hip (TH). Secondary outcome measures were fracture incidence, bone pain, and change in bone turnover markers (serum procollagen type I aminopropeptide (P1NP) and bone ALP). A meta-analysis of published studies of oral bisphosphonates in adults and children with OI was performed.

RESULTS

Twenty-seven participants (ten males and seventeen females) completed the study. BMD increased at LS by 3.9% (0.815 vs. 0.846 g/cm(2), p = 0.007; mean Z-score, -1.93 vs. -1.58, p = 0.002), with no significant change at TH. P1NP fell by 37% (p = 0.00041), with no significant change in bone ALP (p = 0.15). Bone pain did not change significantly (p = 0.6). Fracture incidence remained high, with 25 clinical fractures and 10 major fractures in fourteen participants (0.18 major fractures per person per year), with historical data of 0.12 fractures per person per year. The meta-analysis did not demonstrate a significant difference in fracture incidence in patients with OI treated with oral bisphosphonates.

CONCLUSIONS

Risedronate in adults with OI type I results in modest but significant increases in BMD at LS, and decreased bone turnover. However, this may be insufficient to make a clinically significant difference to fracture incidence.

Effects of forage type, body condition and single-nucleotide polymorphisms in the bovine cytochrome P450 regulatory region on cow productivity

Single-nucleotide polymorphisms (SNP) in the coding sequence of cytochrome p450 (CYP3A28) have been associated with milk yield and composition, and calving traits in cows. In this study, we aimed to determine whether (i) the CYP3A28 regulatory region was polymorphic and (ii) SNP genotype, forage type, body condition and their interactions affect cow productivity. Primers for CYP3A28 promoter were designed to amplify a 483-bp segment by PCR. Amplicon sequences revealed seven SNP (T-318C, T-113A, C-189T, T-78G, A6G, G17A and T21C) in Brahman (38 cows), Brahman x Angus reciprocal crosses (47 cows) and crossbreds (98 cows). Angus cows (n = 41) appeared to be fixed at those SNP locations. Genotype and forage {endophyte-infected tall fescue [KY+; Lolium arundinaceum (Schreb.) S. J. Darbyshire] vs. bermudagrass [Cynodon dactylon (L.) Pers.]} effects on lifetime (8-years) calving rate, and calf weaning weights and heights were determined in Herd 1 (126 cows); genotype and BC (low vs. moderate) effects on calving date and calving percent were determined in Herd 2 (98 cows). Four SNP (T-318C, T-113A, A06G and T21C) appeared to be related to cattle productivity, CC cows at T-318C having a lower (p < 0.05) lifetime calving rate than TC or TT cows (65%, 85% and 81% respectively). Cows that grazed KY+ and were TT at T-318C produced calves that tended (p < 0.07) to weigh less than their contemporaries. Moreover, calves of TT cows were shorter (p < 0.05) at weaning than calves of CC or TC cows. In Herd 2, moderate-BC cows that were TT or AA at T-318C, T-113A, T-78G, A6G and T21C had greater (p < 0.05) calving rates (74-80%) than heterozygous cows (46-60%), and low-BC cows that were AA at G17A calved at least 6 days earlier (p < 0.05) than heterozygous cows. Our findings suggest that SNP in the CYP3A28 regulatory region of Brahman-influenced cows are associated with cattle productivity.

Effects of bovine cytochrome P450 single-nucleotide polymorphism, forage type and body condition on production traits in cattle

Relating single-nucleotide polymorphisms (SNP) to cows with acceptable productivity could benefit cattle breeders in areas where tall fescue is the predominant forage. This study aimed to (i) identify SNPs in bovine cytochrome P450 3A28 (CYP3A28) and (ii) determine the associations between SNP genotype, forage and cow body condition (BC). Genotype (CC, CG or GG) and forage [Kentucky-31 wild-type endophyte-infected tall fescue (KY+) vs. bermudagrass] effects on milk volume and quality were determined in Herd 1 cows (123 cows); in Herd 2 (99 cows), genotype and BC (low vs. moderate) effects on ovarian follicle size, calving date and calving per cent were determined; and in Herd 3 (114 cows), effects of genotype and fescue cultivar [KY+ vs. non-toxic endophyte-infected tall fescue (HiMag4)] were related to calving per cent, calving date and weaning weights of both cow and her calf. A cytosine (C) to guanine (G) transversion at base 994 (C994G) in CYP3A28 was identified. There was a genotype × forage type interaction (p < 0.05) on milk protein in Herd 1 cows; CC cows grazing bermudagrass had greater milk protein percentage in relation to other cows in the herd. In Herd 2, BC and genotype × BC tended (p < 0.10) to influence follicle size and Julian calving date respectively. Diameter of the largest follicle tended to be larger in moderate BC than in low-BC cows; whereas, CC and CG cows in moderate BC and homozygous (CC and GG) cows in low BC tended to calve 14 days earlier in relation to CG cows in low BC. In Herd 3, there was a genotype × forage type interaction (p < 0.05) on calving per cent, Julian calving date and calf weaning weight. In this study, genetic alterations (G allele at C994G) coupled with nutritional factors (low BC and toxic tall fescue) resulted in overall lower productivity in cows.

Elucidating the chromosome 9 association with AS; CARD9 is a candidate gene

Ankylosing spondylitis (AS) is polygenic with contributions from the immunologically relevant genes HLA-B*27, ERAP1 and IL23R. A recent genome-wide association study (GWAS) identified associations (p~0.005) with the non-synonymous single nucleotide polymorphisms (nsSNPs), rs4077515 and rs3812571, in CARD9 and SNAPC4 on chromosome 9q that had previously been linked to AS. We replicated these associations in a study of 730 AS patients compared to 2879 historic disease controls, (rs4077515 p = 0.0004 odds ratio (OR) (95% confidence interval) = 1.2 (1.1-1.4); rs3812571 p = 0.0003 OR = 1.2 (1.1-1.4)). Meta-analysis revealed strong associations of both SNPs with AS, rs4077515 p = 0.000005 OR = 1.2 (1.1-1.3) and rs3812571 p = 0.000006 OR = 1.2 (1.1-1.3). We then typed 1604 AS cases and 1020 controls for 13 tagging SNPs; 6 showed at least nominal association, 5 of which were in CARD9. We imputed genotypes for 13 additional SNPs but none was more strongly associated with AS than the tagging SNPs. Finally, interrogation of an mRNA expression database revealed that the SNPs most strongly associated AS (or in strong linkage disequilibrium) were those most associated with CARD9 expression. CARD9 is a plausible candidate for AS given its central role in the innate immune response.

Interaction of breed type and endophyte-infected tall fescue on milk production and quality in beef cattle

Decreased milk production of beef cattle grazing endophyte-infected (EI) tall fescue (TF), an important cool season grass in the southeastern United States, can affect calf growth. The objective was to determine whether a thermal or heat-tolerant Bos taurus breed of cattle, Romosinuano (RO), would tolerate EI TF toxins relative to Angus (AN) cattle. Milk production and quality were examined on AN and RO cows grazing endophyte-free (EF; variety K-31; n = 36) or EI TF (variety K-31; n = 37) along with growth of their Charolais-sired calves in 2007 and 2008 in west central Arkansas. Cows calved between early February and late March (spring). Milk yield and quality, BW, rectal temperature, and serum prolactin were determined at 57.1 +/- 2.6 d postpartum and every 28 d thereafter between April and August. Milk yield was greater in AN compared with RO cows (P < 0.001), but not influenced by forage type (P > 0.88). Percent milk fat was greater in cows grazing EF TF in April, but greater for cows grazing EI TF in July (forage x month, P < 0.001). Percent milk fat was greater for RO than AN cows (P < 0.001). Percent milk protein (P < 0.001) was greater and somatic cell counts (log-transformed; P < 0.001) were less in RO than AN cows. Milk lactose was greater for RO compared with AN cows in June through August (breed x month, P = 0.004). Adjusted weaning BW of calves was similar between EF and EI TF in 2007, but greater for calves from EF than EI TF in 2008 (forage x year, P = 0.03). Rectal temperature was similar between RO cows grazing EF and EI TF, but greater in AN cows grazing EI compared with EF TF in most months (forage x breed x month x year, P < 0.001). Serum prolactin was reduced in both breeds of cows grazing EI TF between April and July of both years and greatest in RO cows grazing EF TF (breed, P < 0.001; forage x month, P < 0.001). These data suggest that RO cows were more thermal-tolerant, but still susceptible to toxins in EI TF as shown by a reduction in serum concentrations of prolactin. However, milk production was not influenced by EI TF as previously observed, but milk fat percent was decreased in early lactation in this group of cows. Milk yield and quality were different between AN and RO cows during the period of lactation observed.

Striving for the impossible dream: a community-based multi-practice collaborative model of diabetes management

AIMS

In 1994 the Centre for Diabetes and Endocrinology (CDE) based in Johannesburg, South Africa established a novel community-based capitation and risk-sharing model for diabetes management. We here describe the model and present a recent survey of the performance/outcomes of this unique diabetes care programme.

METHODS

Data on 17 043 patients managed by the CDE Diabetes Management Programme at its Centre and its 262 affiliated Centres were analysed from its national database. From this total cohort, 1520 Type 1 and 8026 Type 2 diabetes patients have been in the Programme for > 5 years. The 5-year outcome data on hospital admission rates, glycaemic control (HbA(1c)), and microvascular complication rates were assessed in this subgroup of patients.

RESULTS

Major reductions in hospital admission rates for both acute metabolic emergencies and all causes (40% overall) were achieved in patients enrolled onto the Diabetes Management Programme. The mean HBA(1c) on enrolment was 9.2% for subjects with Type 1 and 8.8% for those with Type 2 diabetes. After 1 year, mean HbA(1c) fell to 7.6% and 7.3% for the Type 1 and Type 2 subjects, respectively. At 5 years the HbA(1c) remained similar at 7.7% for the Type 1 subjects and 7.4% for the Type 2 subjects, demonstrating sustained improvement. Progression of microvascular complications appears to have been delayed.

CONCLUSIONS

This managed care model of diabetes care in the context of the South African Private Health Care System achieved long-term improvement in glycaemic control and all-cause hospital admission rates. This may be due to the cost-containment being in the hands of the treating doctor, supported by an annual training programme. This programme is based on an individualized and holistic approach encompassing intensive patient education to facilitate self-empowerment and including prompting for the management of risk factors.

Predominant association of HLA-B*2704 with ankylosing spondylitis in Chinese Han patients

The HLA-B27 subtypes have a varied racial and ethnic prevalence throughout the world. However, the association of B27-subtypes with ankylosing spondylitis (AS) in the mainland China is unknown. To determine the association of B27-subtypes with AS in the Mainland Chinese Han population, a total of unrelated 153 patients with AS were enrolled in a large case-control association study, and 1545 unrelated, healthy, ethnically matched blood donors were included as controls. The genotyping of B27 and its subtypes was performed using the polymerase chain reaction with sequence specific primers (PCR-SSP). A total of 130 (84.97%) AS patients and 61 (3.95%) healthy controls were B27 positive. Three B27-subtypes, B*2704, B*2705 and B*2710, were further identified, of which both B*2704 and B*2705 were strongly AS associated. B*2710 was only detected in one AS patient and two other healthy controls. Considering only B27-positive cases and controls, a statistically different frequency of B27-subtypes was observed, with an over-representation of B*2704 (P = 0.018). B*2704 was clearly more strongly associated than B*2705 with AS [odds ratio (OR ) = 2.4, P = 0.011]. Furthermore, a combined analysis including three previous studies of B27-subtype distributions in Chinese AS cases confirmed the stronger association of B*2704 with AS than B*2705 (OR = 2.5, P = 0.00094).

Association of IL23R and ERAP1 genes with ankylosing spondylitis in a Portuguese population

OBJECTIVE

Association between ankylosing spondylitis (AS) and two genes, ERAP1 and IL23R, has recently been reported in North American and British populations. The population attributable risk fraction for ERAP1 in this study was 25%, and for IL23R, 9%. Confirmation of these findings to ERAP1 in other ethnic groups has not yet been demonstrated. We sought to test the association between single nucleotide polymorphisms (SNPs) in these genes and susceptibility to AS among a Portuguese population. We also investigated the role of these genes in clinical manifestations of AS, including age of symptom onset, the Bath Ankylosing Spondylitis Disease Activity, Metrology and Functional Indices, and the modified Stoke Ankylosing Spondylitis Spinal Score.

METHODS

The study was conducted on 358 AS cases and 285 ethnically matched Portuguese healthy controls. AS was defined according to the modified New York Criteria. Genotyping of IL23R and ERAP1 allelic variants was carried out with TaqMan allelic discrimination assays. Association analysis was performed using the Cochrane-Armitage and linear regression tests of genotypes as implemented in PLINK for dichotomous and quantitative variables respectively. A meta-analysis for Portuguese and previously published Spanish IL23R data was performed using the StatsDirect Statistical tools, by fixed and random effects models.

RESULTS

A total of 14 nsSNPs markers (8 for IL23R, 5 for ERAP1, 1 for LN-PEP) were analysed. Three markers (2 for IL23R and 1 for ERAP1) showed significant single-locus disease associations, confirming that the association of these genes with AS in the Portuguese population. The strongest associated SNP in IL23R was rs1004819 (OR=1.4, p=0.0049), and in ERAP1 was rs30187 (OR=1.26, p=0.035). The population attributable risk fractions in the Portuguese population for these SNPs are 11% and 9.7% respectively. No association was seen with any SNP in LN-PEP, which flanks ERAP1 and was associated with AS in the British population. No association was seen with clinical manifestations of AS.

CONCLUSION

These results show that IL23R and ERAP1 genes are also associated with susceptibility to AS in the Portuguese population, and that they contribute a significant proportion of the population risk for this disease.

Genetics of ankylosing spondylitis and rheumatoid arthritis: where are we at currently, and how do they compare?

Both ankylosing spondylitis (AS) and rheumatoid arthritis (RA) are common, highly heritable conditions, the pathogenesis of which are incompletely understood. Gene-mapping studies in both conditions have over the last couple of years made major breakthroughs in identifying the mechanisms by which these diseases occur. Considering RA, there is an over-representation of genes involved in TNF signalling and the NFKappaB pathway that have been shown to influence the disease risk. There is also considerable sharing of susceptibility genes between RA and other autoimmune diseases such as systemic lupus erythematosus, type 1 diabetes, autoimmune thyroid disease and celiac disease, with thus far little overlap with AS. In AS, genes involved in response to IL12/IL23, and in endoplasmic reticulum peptide presentation, have been identified, but a full genomewide association study has not yet been reported.

Analysis of killer immunoglobulin-like receptor genes in ankylosing spondylitis

OBJECTIVES

To assess the possible association of killer immunoglobulin-like receptor (KIR) genes, specifically KIR3DL1, KIR3DS1 and KIR3DL2, with ankylosing spondylitis (AS).

METHODS

14 KIR genes were genotyped in 200 UK patients with AS and 405 healthy controls using multiplex polymerase chain reaction. Sequence-specific oligonucleotide probes were used to subtype 368 cases with AS and 366 controls for 12 KIR3DL2 alleles. Differences in KIR genotypes and KIR3DL2 allele frequencies were assessed using the chi(2) test.

RESULTS

KIR3DL1 and KIR3DS1 gene frequencies were very similar in cases with AS and controls (odds ratio = 1.5, 95% confidence interval 0.8 to 3.0, and odds ratio = 1.02, 95% confidence interval 0.2 to 5.3, respectively). KIR3DL2 allele frequencies were not significantly different between cases with AS and controls.

CONCLUSIONS

Neither the KIR gene content of particular KIR haplotypes nor KIR3DL2 polymorphisms contribute to AS.

Fine mapping of the MHC Class III region demonstrates association of AIF1 and rheumatoid arthritis

OBJECTIVES

The heritability of RA has been estimated to be approximately 55%, of which the MHC contributes about one-third. HLA-DRB1 alleles are strongly associated with RA, but it is likely that significant non-DRB1 MHC genetic susceptibility factors are involved. Previously, we identified two three-marker haplotypes in a 106-kb region in the MHC class III region immediately centromeric to TNF, which are strongly associated with RA on HLA-DRB1*0404 haplotypes. In the present study, we aimed to refine these associations further using a combination of genotyping and gene expression studies.

METHODS

Thirty-nine nucleotide polymorphisms (SNPs) were genotyped in 95 DRB1*0404 carrying unrelated RA cases, 125 DRB1*0404-carrying healthy controls and 87 parent-case trio RA families in which the affected child carried HLA-DRB1*04. Quantitative RT-PCR was used to assess the expression of the positional candidate MHC class III genes APOM, BAT2, BAT3, BAT4, BAT5, AIF1, C6orf47, CSNK2beta and LY6G5C, and the housekeeper genes, hypoxanthine-guanine phosphoribosyltransferase (HPRT) and beta(2)-microglobulin (B2M) in 31 RA cases and 21 ethnically, age- and sex-matched healthy controls. Synovial membrane specimens from RA, PsA and OA cases were stained by an indirect immunoperoxidase technique using a mouse-anti-human AIF1 monoclonal antibody.

RESULTS

Association was observed between RA and single markers or two marker haplotypes involving AIF1, BAT3 and CSNK. AIF1 was also significantly overexpressed in RA mononuclear cells (1.5- to 1.9-fold difference, P = 0.02 vs HPRT, P = 0.002 vs B2M). AIF1 protein was clearly expressed by synovial macrophages in all the inflammatory synovial samples in contrast to the non-inflammatory OA samples.

CONCLUSIONS

The results of the genotyping and expression studies presented here suggest a role for AIF1 in both the aetiology and pathogenesis of RA.

Engaging recreational fishers in management and conservation: global case studies

Globally, the number of recreational fishers is sizeable and increasing in many countries. Associated with this trend is the potential for negative impacts on fish stocks through exploitation or management measures such as stocking and introduction of non-native fishes. Nevertheless, recreational fishers can be instrumental in successful fisheries conservation through active involvement in, or initiation of, conservation projects to reduce both direct and external stressors contributing to fishery declines. Understanding fishers' concerns for sustained access to the resource and developing methods for their meaningful participation can have positive impacts on conservation efforts. We examined a suite of case studies that demonstrate successful involvement of recreational fishers in conservation and management activities that span developed and developing countries, temperate and tropical regions, marine and freshwater systems, and open- and closed-access fisheries. To illustrate potential benefits and challenges of involving recreational fishers in fisheries management and conservation, we examined the socioeconomic and ecological contexts of each case study. We devised a conceptual framework for the engagement of recreational fishers that targets particular types of involvement (enforcement, advocacy, conservation, management design [type and location], research, and monitoring) on the basis of degree of stakeholder stewardship, scale of the fishery, and source of impacts (internal or external). These activities can be enhanced by incorporating local knowledge and traditions, taking advantage of leadership and regional networks, and creating collaborations among various stakeholder groups, scientists, and agencies to maximize the probability of recreational fisher involvement and project success.

Synthesis of PbTe nanowire arrays using lithographically patterned nanowire electrodeposition

We describe the preparation by electrodeposition of arrays of lead telluride (PbTe) nanowires using the lithographically patterned nanowire electrodeposition (LPNE) method. PbTe nanowires had a rectangular cross-section with adjustable width and height ranging between 60-400 nm (w) and 20-100 nm (h). The characterization of these nanowire arrays using X-ray diffraction, transmission electron microscopy and electron diffraction, scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy (XPS) is reported. PbTe nanowires were electrodeposited using a cyclic electrodeposition-stripping technique that produced polycrystalline, stoichiometric, face-centered cubic PbTe with a mean grain diameter of 10-20 nm. These nanowires were more than 1 mm in length and two additional processing steps permitted their suspension across 25 microm air gaps microfabricated on these surfaces. The LPNE synthesis of lithographically patterned PbTe nanowires was carried out in unfiltered laboratory air. Nanowires with lengths of 70-100 microm showed an electrical resistivity comparable to bulk PbTe. XPS reveals that exposure of PbTe nanowires to air causes the formation on the nanowire surface of approximately one monolayer of a mixed lead oxide and tellurium oxide within a few minutes.