289 research outputs found
Leaf diseases of wheat
Trial 90PE10
Strategic variety mixtures to reduce septoria diseases of wheat. Evaluation of wheat lines for suitability to mixing for septoria control.
Location: Mt. Barker Research Station
To determine components of partial resistance to both Septoria species to ensure that lines with components that are complimentary are chosen for evaluation as mixtures for Septoria control.
Trial 90MT12 and 90ME10
Assessing effects of a paired variety mixture to reduce Septoria.
Location: Borden and Mt Barker Research Station.
To assess the effects of a variety mixture on Septoria diseases.
Trial 90MT11 and 90JE9
Evaluating variety mixtures to reduce septoria, using a range of crossbreds.
Location: Mt. Barker Research Station
To identify varietal combinations from a range of genotypes for using in mixtures to reduce Septoria diseases.
Trial 90BA50 and 90MT60
Mixing varieties with a range of maturities for possible disease and agronomic benefits.
Location: Badgingarra Research Station and Mt Barker Research Station.
To evaluate disease control and other agronomic effects from growing varieties with different maturities as mixtures.
Glasshouse screening for resistance to S. nodorum in wheat (with R.E. Wilson)
During the year 16 sets of material were screened. Material comprised stage 1.2 and stage 2 lines as well as experimental Triticum tauschii material.
Tests were conducted on Triticum tauschii lines and synthetic hexaploid derivatives. Derivatives are called synthetic because their production imitates the natural cross of durum with the primitive grass species %. tauschii which in theory resulted in the first bread wheat.
Trial 90MT15 and 90E12
Time of planting and variety effects on septoria diseases of wheat. (with W. Smith, Esperance)
Location: Mt. Barker Research Station and Esperance Downs Research Station.
To establish earliest practical planting times for differing varieties to minimize the impact of Septoria diseases and maximize yield.
Trial 90BA15 (90ES20 was discontinued because of very severe Rhizoctonia and absence of leaf disease)
Location: Badgingarra Research Station.
To compare a range of new products for control of Septoria diseases with the current standard chemical - TILT.
Trial 90A4
Is seed infection a significant source of early inoculum of septoria nodorum?
Location: Avondale Research Station.
To evaluate the effect of seed borne infection of S. nodorum as early season inoculum.
Are ascospores a significant source of infection of septoria nodorum?
Location: Badgingarra and Mt Barker Research Station.
To determine the extent of ascospore dispersal of Leptosphaeria nodorwn from wheat stubble.
Unusual disease occurrence.
Leaf rust (Puccinia recondita) of wheat
Location: Esperance and Mt. Barker, Jerramungup
Leaf rust has occurred in Western Australia, perhaps for the first time in over 10 years. A late wheat leaf rust epidemic developed along the south coast between Esperance and Mt Barker.
It was first apparent at trace levels on early-sown crops in September around Esperance. Because rainfall was below average in many areas until October, the rust did not increase until late in the season. It reached yield-damaging levels in some later sown crops with severe epidemics observed in the Esperance and Jerramungup districts. The rust strain is new to Western Australia. Its mode of entry is unknown but is likely to have been by wind from South Australia and its appearance relatively early in 1990 suggests it reached Western Australia in 1989. It apparently remained undetected, surviving through a summer with favourable rains
A functional link between bone morphogenetic proteins and insulin-like peptide 3 signaling in modulating ovarian androgen production
Bone morphogenetic proteins (BMP) are firmly implicated as intra-ovarian regulators of follicle development and steroidogenesis. Here we report a microarray analysis showing that treatment of cultured bovine theca cells (TC) with BMP6 significantly (>2-fold; P<0.01) up- or down-regulated expression of 445 genes. Insulin-like peptide 3 (INSL3) was the most heavily down-regulated gene (-43-fold) with CYP17A1 and other key transcripts involved in TC steroidogenesis including LHCGR, INHA, STAR, CYP11A1 and HSD3B1 also down-regulated. BMP6 also reduced expression of NR5A1 encoding steroidogenic factor-1 known to target the promoter regions of the aforementioned genes. Real-time PCR confirmed these findings and also revealed a marked reduction in expression of INSL3 receptor (RXFP2). Secretion of INSL3 protein and androstenedione were also suppressed suggesting a functional link between BMP and INSL3 pathways in controlling androgen synthesis. RNAi-mediated knockdown of INSL3 reduced INSL3 mRNA and secreted protein level (75 and 94%, respectively) and elicited a 77% reduction in CYP17A1 mRNA level and 83% reduction in androstenedione secretion. Knockdown of RXFP2 also reduced CYP17A1 mRNA level (81%) and androstenedione secretion (88%). Conversely, treatment with exogenous (human) INSL3 increased androstenedione secretion ~2-fold. The CYP17 inhibitor abiraterone abolished androgen secretion and reduced expression of both INSL3 and RXFP2. Collectively, these findings indicate a positive autoregulatory role for INSL3 signaling in maintaining thecal androgen production, and visa versa. Moreover, BMP6-induced suppression of thecal androgen synthesis may be mediated, at least in part, by reduced INSL3-RXFP2 signaling
Development of a scaffold displaying exoloops of RXFP1
Relaxin family peptide receptor 1 (RXFP1), the cognate receptor for relaxin, is a G-protein coupled receptor (GPCR) possessing a unique extracellular region consisting of a domain of 10 leucine rich repeats (LRRs) linked to an N-terminal low density lipoprotein Class A module. Relaxin binds to its receptor primarily by a high affinity interaction with the LRRs. An additional low-affinity interaction has been proposed to occur between relaxin and the the exoloops (ELs) of the transmembrane domain, however the molecular detail of this interaction remains undefined. While site directed mutagenesis and subsequent functional characterisation of these mutants traditionally allows identification of residues contributing to receptor function, in this case results are complicated by the presence of the high affinity binding site in the LRRs. To create a tool to investigate the low-affinity interaction, a protein scaffold system displaying exoloops 1 and 2 from RXFP1 was designed. This was achieved by inserting RXFP1 exoloops 1 and 2 into the native loops of a thermostabilised 6 kDa GB1 protein creating EL1/EL2-GB1. This protein has been expressed and purified in milligram quantities and used in conjunction with biophysical techniques such as NMR to explore relaxin binding to the exoloops of RXFP1
Realβtime examination of cAMP activity at relaxin family peptide receptors using a BRET βbased biosensor
INSL3 in the Ruminant: A Powerful Indicator of Gender- and Genetic-Specific Feto-Maternal Dialogue
The hormone Insulin-like peptide 3 (INSL3) is a major secretory product of the Leydig cells from both fetal and adult testes. Consequently, it is a major gender-specific circulating hormone in the male fetus, where it is responsible for the first phase of testicular descent, and in the adult male. In most female mammals, circulating levels are very low, corresponding to only a small production of INSL3 by the mature ovaries. Female ruminants are exceptional in exhibiting high INSL3 gene expression by the thecal cells of antral follicles and by the corpora lutea. We have developed a specific and sensitive immunoassay to measure ruminant INSL3 and show that, corresponding to the high ovarian gene expression, non-pregnant adult female sheep and cows have up to four times the levels observed in other female mammals. Significantly, this level declines during mid-pregnancy in cows carrying a female fetus, in which INSL3 is undetectable. However, in cows carrying a male fetus, circulating maternal INSL3 becomes elevated further, presumably due to the transplacental transfer of fetal INSL3 into the maternal circulation. Within male fetal blood, INSL3 is high in mid-pregnancy (day 153) corresponding to the first transabdominal phase of testicular descent, and shows a marked dependence on paternal genetics, with pure bred or hybrid male fetuses of Bos taurus (Angus) paternal genome having 30% higher INSL3 levels than those of Bos indicus (Brahman) paternity. Thus INSL3 provides the first example of a gender-specific fetal hormone with the potential to influence both placental and maternal physiology
The inter-relationship of symptom severity and quality of life in 2055 patients with primary biliary cholangitis
BackgroundAge at presentation with primary biliary cholangitis (PBC) is associated with differ-ential response to ursodeoxycholic acid (UDCA) therapy. Younger-presentingpatients are less likely to respond to treatment and more likely to need transplantor die from the disease. PBC has a complex impact on quality of life (QoL), withsystemic symptoms often having signiο¬cant impact.AimTo explain the impact of age at presentation on perceived QoL and the inter-related symptoms which impact upon it.MethodsUsing the UK-PBC cohort, symptoms were assessed using the PBC-40 and othervalidated tools. Data were available on 2055 patients.ResultsOf the 1990 patients reporting a global PBC-QoL score, 66% reported good/neutralscores and 34% reported poor scores. Each 10-year increase in age at presentationwas associated with a 14% decrease in risk of poor perceived QoL (OR = 0.86,95% CI: 0.75β0.98, P < 0.05). All sympto m domains were similarly age-associated(P < 0.01). Social dysfunction was the symptom factor with the greatest impa ct onQoL. Median (interquartile range) PBC-40 social scores for patient s with good per-ceived QoL were 18 (14β23) compared with 34 (29β39) for those with poor QoL.ConclusionThe majo rity of patients with primary biliary cholangitis do not feel their QoL isimpaired, although impairment is reported by a sizeable minority. Age at presenta-tion is associated with impact on per ceived QoL and the symptoms impairing it,with younger patients being more affected. Social dysfunction makes the greatestcontribution to QoL impairment, and it should be targeted in trials aimed atimproving life quality
Solution structure and novel insights into the determinants of the receptor specificity of human relaxin-3
Relaxin- 3 is the most recently discovered member of the relaxin family of peptide hormones. In contrast to relaxin- 1 and - 2, whose main functions are associated with pregnancy, relaxin- 3 is involved in neuropeptide signaling in the brain. Here, we report the solution structure of human relaxin- 3, the first structure of a relaxin family member to be solved by NMR methods. Overall, relaxin- 3 adopts an insulin- like fold, but the structure differs crucially from the crystal structure of human relaxin- 2 near the B- chain terminus. In particular, the B- chain C terminus folds back, allowing Trp(B27) to interact with the hydrophobic-core. This interaction partly blocks the conserved RXXXRXXI motif identified as a determinant for the interaction with the relaxin receptor LGR7 and may account for the lower affinity of relaxin- 3 relative to relaxin for this receptor. This structural feature is likely important for the activation of its endogenous receptor, GPCR135
Does a SLAP lesion affect shoulder muscle recruitment as measured by EMG activity during a rugby tackle?
Background: The study objective was to assess the influence of a SLAP lesion on onset of EMG activity in shoulder muscles during a front on rugby football tackle within professional rugby players.
Methods: Mixed cross-sectional study evaluating between and within group differences in EMG onset times. Testing was carried out within the physiotherapy department of a university sports medicine clinic. The test group consisted of 7 players with clinically diagnosed SLAP lesions, later verified on arthroscopy. The reference group consisted of 15 uninjured and full time professional rugby players from within the same playing squad. Controlled tackles were performed against a tackle dummy. Onset of EMG activity was assessed from surface EMG of Pectorialis Major, Biceps Brachii, Latissimus Dorsi, Serratus Anterior and Infraspinatus muscles relative to time of impact. Analysis of differences in activation timing between muscles and limbs (injured versus non-injured side and non injured side versus matched reference group).
Results: Serratus Anterior was activated prior to all other muscles in all (P = 0.001-0.03) subjects. In the SLAP
injured shoulder Biceps was activated later than in the non-injured side. Onset times of all muscles of the noninjured shoulder in the injured player were consistently earlier compared with the reference group. Whereas, within
the injured shoulder, all muscle activation timings were later than in the reference group.
Conclusions: This study shows that in shoulders with a SLAP lesion there is a trend towards delay in activation time of Biceps and other muscles with the exception of an associated earlier onset of activation of Serratus anterior, possibly due to a coping strategy to protect glenohumeral stability and thoraco-scapular stability. This
trend was not statistically significant in all cases
Hip abduction weakness in elite junior footballers is common but easy to correct quickly: a prospective sports team cohort based study
Background: Hip abduction weakness has never been documented on a population basis as a common finding in a healthy group of athletes and would not normally be found in an elite adolescent athlete. This study aimed to show that hip abduction weakness not only occurs in this group but also is common and easy to correct with an unsupervised home based program. Methods: A prospective sports team cohort based study was performed with thirty elite adolescent under-17 Australian Rules Footballers in the Australian Institute of Sport/Australian Football League Under-17 training academy. The players had their hip abduction performance assessed and were then instructed in a hip abduction muscle training exercise. This was performed on a daily basis for two months and then they were reassessed.Results: The results showed 14 of 28 athletes who completed the protocol had marked weakness or a side-to-side difference of more than 25% at baseline. Two months later ten players recorded an improvement of β₯ 80% in their recorded scores. The mean muscle performance on the right side improved from 151 Newton (N) to 202 N (p<0.001) while on the left, the recorded results improved from 158 N to 223 N (p<0.001). Conclusions: The baseline values show widespread profound deficiencies in hip abduction performance not previously reported. Very large performance increases can be achieved, unsupervised, in a short period of time to potentially allow large clinically significant gains. This assessment should be an integral part of preparticipation screening and assessed in those with lower limb injuries. This particular exercise should be used clinically and more research is needed to determine its injury prevention and performance enhancement implications
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