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1.
Semin Arthritis Rheum ; 49(1): 20-26, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30685064

RESUMO

OBJECTIVE: Treat-to-target in rheumatoid arthritis (RA) recommends targeting remission, with low disease activity (LDA) being an alternative goal. When deciding to target remission or LDA, important considerations are the likelihood of attaining them, and their impacts on function and health-related quality of life (HRQoL). We have addressed this by studying: (a) the frequency of remission and LDA/remission; (b) DAS28-ESR trends after remission; (c) ability of remission vs. LDA to identify patients with normal function (HAQ ≤ 0.5) and HRQoL (EQ-5D ≥ the normal population). METHODS: We studied 571 patients in two clinical trials, and 1693 patients in a 10-year routine care cohort. We assessed the frequency and sustainability of remission and LDA/remission, variability in DAS28-ESR after remission, and sensitivity/specificity of remission and LDA/remission at identifying patients with low disability levels and normal HRQoL using Receiver Operator Characteristic (ROC) curves. RESULTS: Point remission and remission/LDA were common (achieved by 35-58% and 49-74% of patients, respectively), but were rarely sustained (sustained remission and remission/LDA achieved by 5-9% and 9-16% of patients, respectively). Following attaining remission, DAS28-ESR levels varied substantially. Despite this, of those patients attaining point remission, the majority (53-61%) were in remission at study end-points. Whilst remission was highly specific at identifying patients with low disability (85-91%) it lacked sensitivity (51-57%); similar findings were seen for normal HRQoL (specificity 78-86%; sensitivity 52-59%). The optimal DAS28-cut-off to identify individuals with low disability and normal HRQoL was around the LDA threshold. CONCLUSIONS: Our findings support both the treat-to-target goals. Attaining remission is highly specific for attaining low disability and normal HRQoL, although many patients with more active disease also have good function and HRQoL. Attaining a DAS28-ESR ≤ 3.2 has a better balance of specificity and sensitivity for attaining these outcomes, with the benefit of being more readily achievable. Although sustaining these targets over time is rare, even attaining them on a one-off basis leads to better function and HRQoL outcomes for patients.


Assuntos
Artrite Reumatoide/diagnóstico , Avaliação da Deficiência , Qualidade de Vida , Adulto , Idoso , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Índice de Gravidade de Doença , Resultado do Tratamento
2.
BMC Rheumatol ; 2: 32, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30886982

RESUMO

Although treat-to-target has revolutionised the outcomes of patients with rheumatoid arthritis (RA) there is emerging evidence that attaining the target of remission is insufficient to normalise patients' quality of life, and ameliorate the extra-articular impacts of RA. RA has a broad range of effects on patient's lives, with four key "extra-articular" impacts being pain, depression and anxiety, fatigue and rheumatoid cachexia. All of these are seen frequently; for example, studies have reported that 1 in 4 patients with RA have high-levels of fatigue. Commonly used drug treatments (including simple analgesics, non-steroidal anti-inflammatory drugs and anti-depressants) have, at most, only modest benefits and often cause adverse events. Psychological strategies and dynamic and aerobic exercise all reduce issues like pain and fatigue, although their effects are also only modest. The aetiologies of these extra-articular impacts are multifactorial, but share overlapping components. Consequently, patients are likely to benefit from management strategies that extend beyond the assessment and treatment of synovitis, and incorporate more broad-based, or "holistic", assessments of the extra-articular impacts of RA and their management, including non-pharmacological approaches. Innovative digital technologies (including tablet and smartphone "apps" that directly interface with hospital systems) are increasingly available that can directly capture patient-reported outcomes during and between clinic visits, and include them within electronic patient records. These are likely to play an important future role in delivering such approaches.

3.
RMD Open ; 2(2): e000270, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27651924

RESUMO

OBJECTIVES: To establish if using intensive treatment to reduce synovitis and attain remission in active rheumatoid arthritis (RA) improves all aspects of health-related quality of life (HRQoL). METHODS: A secondary analysis of two randomised clinical trials (CARDERA and TACIT) was undertaken. CARDERA randomised 467 patients with early active RA to different disease-modifying antirheumatic drug (DMARD) regimens, including high-dose tapering corticosteroids. TACIT randomised 205 established patients with active RA to combination DMARDs (cDMARDs) or tumour necrosis factor-α inhibitors (TNFis). Short-Form 36 (SF-36) measured HRQoL across eight domains, generating physical (PCS) and mental (MCS) component summary scores. Linear regression evaluated 6-month intensive treatment impacts. Mean SF-36 scores, stratified by end point disease activity category, were compared with age/gender-matched population scores. RESULTS: In CARDERA, intensive corticosteroid treatment gave significantly greater improvements in PCS but not MCS scores relative to placebo. In TACIT, all eight SF-36 domains had improvements from baseline exceeding minimal clinically important differences with cDMARDs and TNFis. Significantly greater improvements with TNFi relative to cDMARDs were reported in PCS only (p=0.034), after adjusting for covariates. Remission provided the best SF-36 profiles, but scores in physical functioning, role physical and general health in both trials remained below normative values. Patient global assessment of disease activity had a greater association with HRQoL than other disease activity score (DAS28) components. CONCLUSIONS: Intensive corticosteroid treatment in early RA improves physical but not mental health, relative to placebo. In established RA, cDMARDs and TNFi provide similar improvements in HRQoL. As remission optimises but fails to normalise HRQoL, a focus on treatment strategies targeting HRQoL is required. TRIAL REGISTRATION NUMBERS: CARDERA was registered as ISRCTN 32484878. TACIT was registered as ISRCTN 37438295; pre-results.

4.
Vet Immunol Immunopathol ; 169: 102-10, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26620077

RESUMO

This study compared in vivo lymph node gene expression levels between six young red deer that were either relatively resistant (R) or susceptible (S) to paratuberculosis following experimental challenge with Mycobacterium avium subsp. paratuberculosis. Intestinal lymph nodes were biopsied at 4, 12 and 50 weeks post challenge (pc) and parallel changes in histopathology, immunology and bacterial load monitored. SOLiD SAGE (serial analysis of gene expression) next generation sequencing of biopsied lymph node samples generated a total of 373 million transcript tags 26-28bp in length after filtering. A total of 36,632 unique transcripts were identified and 14,325 of these were able to be annotated. The copy number of each transcript was counted, averaged and compared for R and S animals (R-S). P values and False Discovery Rates (FDR) were calculated for each transcript. Genes differentially upregulated ≥2 fold (FDR<0.5) totalled 9, 40 and 32 in R animals (+ values) and 23, 164 and 47 in S animals (- values) at weeks 4, 12, and 50pc, respectively. Transcripts displaying greatest differential expression between R and S animals at each time point were IFIT2 (189 fold) and S100A8 (-32.7 fold) at week 4, LRR1 (52.7 fold), SERPINF2 (-214.6 fold) at week 12 and CEACAM8 (84.6 fold), and STK31 (-129.5 fold) at week 50, respectively. All 9 genes significantly upregulated at week 4 in R animals relate specifically to host defence and all involve Type I interferon stimulated genes. By contrast genes upregulated in S animals at week 4, relate predominantly to inflammation, but also involve adaptive immune responses, mitochondrial function and apoptosis regulation. At week 12, the genes differentially upregulated in R animals are linked predominantly to regulation of adaptive immunity and mucosal immunity, while many of the genes in S animals are associated with pro-inflammatory interleukins involved with innate and adaptive immunity. These correlated with greater lesion severity and higher MAP numbers in lymph nodes of S animals. By week 50 the number of upregulated genes declined in both groups. A number of genes upregulated in R animals appear to be associated with host resistance and regulation of adaptive immunity, especially CEACAM8. Genes upregulated in S animals involve antigen presentation (ENDOD1) and gut associated immune pathology (HSH2D). In conclusion, gene expression in jejunal lymph nodes of resistant and susceptible deer infer that the resistant phenotype is associated with pathways of adaptive immunity, while susceptibility is linked with upregulated non-protective pro-inflammatory responses, following experimental MAP infection.


Assuntos
Cervos/microbiologia , Jejuno/metabolismo , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/genética , Animais , Cervos/imunologia , Resistência à Doença/genética , Expressão Gênica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Predisposição Genética para Doença , Linfonodos/imunologia , Linfonodos/metabolismo , Paratuberculose/imunologia , Regulação para Cima
5.
Clin Exp Rheumatol ; 32(5 Suppl 85): S-7-12, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25365082

RESUMO

OBJECTIVES: Counting the number of tender and swollen joints is an important aspect of assessing patients with an inflammatory arthritis. We provide a comprehensive overview of joint counts in inflammatory arthritis. This spans how they are undertaken, their use in clinical and research settings, their limitations and standardisation and who can perform them. METHODS: We reviewed the literature surrounding joint counts in inflammatory arthropathies, with a specific focus on rheumatoid arthritis (RA). RESULTS: The current widely used joint count assesses 28 peripheral joints. In RA these are usually incorporated in a composite score of disease activity, termed the disease activity score on a 28-joint count (DAS28). Assessing 28 joints has a strong 'floor-effect' with most patients in routine practice having low swollen and tender joint counts. Marked between-observer variation exists in joint count scores; although the variation in tender joint counts can be reduced by standardised training its impact on swollen joint counts is uncertain. Fibromyalgia can have a marked impact on tender joint count scores, resulting in a disproportionately high tender joint count to swollen joint count ratio. Although there is evidence that patient-assessed tender joint counts correlate well with those undertaken by physicians, patients are limited assessors of synovitis. CONCLUSIONS: Although joint counts provide an important objective measure of disease activity in clinical practice, they have a number of limitations. Future research may provide a more robust clinical assessment for disease activity in inflammatory arthropathies, which overcomes these issues.


Assuntos
Artrite Reumatoide/diagnóstico , Articulações/patologia , Exame Físico , Artrite Reumatoide/patologia , Artrite Reumatoide/fisiopatologia , Humanos , Articulações/fisiopatologia , Variações Dependentes do Observador , Medição da Dor , Exame Físico/normas , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
6.
Best Pract Res Clin Rheumatol ; 25(4): 447-68, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22137917

RESUMO

Rheumatoid arthritis (RA) is considered to occur when genetic and environmental factors interact to trigger immunopathological changes and consequently an inflammatory arthritis. Over the last few decades, epidemiological and genetic studies have identified a large number of risk factors for RA development, the most prominent of which comprise cigarette smoking and the shared epitope alleles. These risks appear to differ substantially between anti-cyclic citrullinated peptide (ACPA)-positive and ACPA-negative disease. In this article, we will summarise the risk factors for RA development that have currently been identified, outlining the specific gene-environment and gene-gene interactions that may occur to precipitate and perpetuate autoimmunity and RA. We will also focus on how this knowledge of risk factors for RA may be implemented in the future to identify individuals at a high risk of disease development in whom preventative strategies may be undertaken.


Assuntos
Artrite Reumatoide , Autoimunidade/fisiologia , Exposição Ambiental , Interação Gene-Ambiente , Predisposição Genética para Doença , Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Feminino , Humanos , Masculino , Fatores de Risco
7.
Anim Reprod Sci ; 125(1-4): 138-47, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21497465

RESUMO

Reproductive failure of rising-two-year-old (R(2)) hinds and seasonal misalignment between calving and pastoral feed production are two factors limiting reproductive productivity of farmed red deer hinds in New Zealand. This study aimed to better understand processes around female puberty and breeding seasonality by describing the potential breeding season (i.e., oestrous cyclicity) of three red deer genotypes. A total of 27 hinds born in December 2005, representing Eastern European (Cervus elaphus hippelaphus), Western European (C.e. scoticus) and F1 crossbred (C.e. hippelaphus×scoticus) red deer, were blood sampled thrice-weekly for 7-8 months (February-September/October) across two years spanning the potential breeding seasons as R(2)'s in 2007 (i.e., puberty) and as adults in 2008. Plasma progesterone profiles were used to construct breeding cycle histories for each hind. Four R(2) hinds failed to initiate oestrous cycles (i.e., puberty failure). The remaining R(2) hinds, including all F1 hinds, exhibited between two and seven oestrous cycles. F1 hinds were significantly earlier to initiate, and later to terminate, cyclic activity, resulting in a longer mean pubertal breeding season (139 days) than for Eastern (86 days) and Western hinds (86 days). However, the data for R(2) hinds are confounded by live-weight, with the F1 hinds being significantly heavier than other genotypes. There were significant correlations between live-weight and seasonality parameters in 2007. All hinds were cyclic as adults in 2008, exhibiting between four and nine oestrous cycles, and a mean breeding season duration of between 132 (Western) and 137 (F1) days. For adult hinds there were no significant genotype differences in cyclic onset and cessation timing, and no observable relationships between live-weight and any reproductive parameter. However, the mean dates for the onset of the breeding season for all genotypes in 2008 were 2-3 weeks later than normally expected for adult hinds in New Zealand. The reasons for this are unclear but may relate to chronic stress of frequent animal handling. The study has demonstrated that puberty in red deer hinds is associated with a shorter potential breeding season than for adult hinds, and that perturbation of breeding activity appears to be quite common, leading to incidences of puberty failure and possibly other aberrant cyclic events. Live-weight×genotype interactions may influence puberty but do not appear to be strongly expressed in adults. However, the relatively late onset of oestrous cyclicity in the adult hinds may be an artefact of the study that has masked genetic influences on seasonal breeding patterns.


Assuntos
Cervos/fisiologia , Ciclo Estral/fisiologia , Maturidade Sexual/fisiologia , Fatores Etários , Animais , Peso Corporal/fisiologia , Cruzamentos Genéticos , Cervos/sangue , Cervos/genética , Ciclo Estral/genética , Feminino , Genótipo , Nova Zelândia , Progesterona/sangue , Análise de Regressão , Estações do Ano , Maturidade Sexual/genética
8.
Anim Reprod Sci ; 123(3-4): 202-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21190800

RESUMO

A study was conducted to test the hypotheses that exogenous melatonin treatment of 11-13 month-old red deer hinds: (1) advances the timing of first ovulation, (2) increases the proportion of individuals attaining puberty at ∼16 months of age, and (3) reduces the live-weight threshold for attainment of first pregnancy. A total of 3901 rising-2-year-old (R2) hinds within two herds (A and B) across two years either received single melatonin implants on two occasions in summer (n=1399) or were untreated controls (n=2502). Hinds were joined with stags from mid January to mid May, and were subjected to real-time rectal ultrasonography in early June to assess pregnancy status (proxy for puberty attainment) and foetal age for conception date assignment. Live-weights were recorded for each hind in January (12 months of age) as a proxy for weight at puberty. Melatonin treatment of hinds was associated with a significant advancement in mean conception dates in both herds in both years (P<0.05), with a cohort difference in mean dates between treated and control hinds ranging from 9 to 17 days. Analysis of the temporal distribution of conception dates for each cohort revealed bi-modal or tri-modal patterns of conception indicative of conceptions to first or subsequent ovulations (oestrous cycles). Across all cohorts, melatonin treatment was associated with higher conception rates to first ovulation (P<0.05) resulting in greater overall synchrony of conceptions. Regression analysis demonstrated a significant negative slope for conception date against live-weight (P<0.001), but there was no evidence that this slope varied with treatment, herd or year (P>0.05); for every 10kg increase in live-weight conception date was advanced by an average of 1.3 days. In Herd A, melatonin treatment was associated with significantly higher pregnancy rates in both years (90.3% vs. 78.0% in Year 1 and 84.4% vs. 57.1% in Year 2; P<0.05). The principle effect of melatonin treatment was to increase the pregnancy rate of hinds of low body-mass. In Year 1, at 60kg live-weight a logit regression model indicated a pregnancy rate of 52% for untreated hinds and 83% for treated hinds. At 105kg the rate for both cohorts was 90%. In Herd B, melatonin treatment was associated with higher conception rates in both years but these differences were not significant following correction for slight differences in mean live-weight (P>0.05). The study has demonstrated that factors influencing puberty attainment in R2 red deer hinds can vary between populations. In Herd A, in which body mass of hinds immediately prior to their first potential breeding season may have been the principle limiting factor, melatonin treatment appears to have instigated the pubertal process in hinds that would otherwise be of insufficient body mass.


Assuntos
Cervos , Melatonina/administração & dosagem , Prenhez , Maturidade Sexual/efeitos dos fármacos , Animais , Cervos/fisiologia , Implantes de Medicamento , Sincronização do Estro/efeitos dos fármacos , Sincronização do Estro/fisiologia , Feminino , Fertilização/efeitos dos fármacos , Incidência , Melatonina/farmacologia , Gravidez , Taxa de Gravidez , Caracteres Sexuais , Maturidade Sexual/fisiologia , Fatores de Tempo
9.
Clin Exp Dermatol ; 34(1): 49-51, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18681870

RESUMO

A 33-year-old man with recessive dystrophic epidermolysis bullosa presented with a 3-month history of an enlarging mass within scarring on the posterior aspect of the right shoulder. The clinical appearance of the mass with an almost cobbled, verrucous surface, and its rapid evolution suggested the development of a squamous cell carcinoma (SCC) in a chronically scarred site. Histopathological examination of a biopsy taken from the lesion subsequently revealed it to be a verruciform xanthoma. This case shows that benign phenomena can mimic SCC and underlines the need for a biopsy to be taken promptly.


Assuntos
Epidermólise Bolhosa Distrófica/complicações , Xantomatose/complicações , Adulto , Epidermólise Bolhosa Distrófica/genética , Epidermólise Bolhosa Distrófica/patologia , Genes Recessivos , Humanos , Masculino , Ombro , Xantomatose/patologia
10.
J Clin Pathol ; 61(5): 681-3, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18441161

RESUMO

Spinal cord compression from extramedullary haemopoiesis within the spinal epidural space is a rare complication of myelofibrosis and polycythaemia rubra vera (PRV). A 69-year-old male with PRV (later transforming to myelofibrosis) who developed this complication is described here. Due to the uncertainty over its optimal treatment, previous case reports were systematically reviewed to define its presentations, treatments and outcomes. Including the present case this complication has been reported in 21 patients with myelofibrosis and PRV: 17 were male and the mean symptom duration was 7.6 months. Neurological improvement occurred in 14 patients and 12 survived. Seventy-five per cent of patients receiving combined treatment (irradiation with laminectomy or chemotherapy) showed neurological improvement and 100% survived. In contrast, 67% of those receiving single treatments exhibited improved neurology and only 33% survived. It is concluded that spinal cord compression in myelofibrosis and PRV has a high mortality, with combined treatment providing a better prognosis.


Assuntos
Policitemia Vera/complicações , Mielofibrose Primária/complicações , Compressão da Medula Espinal/etiologia , Adulto , Idoso , Terapia Combinada , Feminino , Hematopoese Extramedular , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Compressão da Medula Espinal/diagnóstico , Compressão da Medula Espinal/terapia
11.
Anim Reprod Sci ; 109(1-4): 206-17, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18178346

RESUMO

Recent studies have demonstrated that gestation length of red deer (Cervus elaphus) is highly variable and influenced by various environmental factors, and this may confer survival advantages for neonates. The current study investigated the relationship between conception date and gestation length to test the hypothesis that within-herd synchrony of red deer births is facilitated by a 'push/pull' control over gestation length, such that hinds conceiving early and late in the breeding season have longer and shorter gestation periods, respectively. In Study 1, data on conception and calving dates were obtained for 393 naturally cycling hinds across two herds. In Study 2, conception and calving dates were obtained from 91 hinds in which oestrus/conception were artificially synchronised across a 4-week range of dates spanning the natural rut. Gestation length for each population was analysed by linear regression, fitting conception day followed by terms for the fixed effect which included hind age (pubertal vs. adult), hind genotype (Cervus elaphus scoticus vs. Cervus elaphus hippelaphus and their crossbreds), calf sex, sire genotype (Study 1 only), birth weight and year. In Study 1, both populations of naturally cycling hinds exhibited highly significant (P<0.001) negative slopes (-0.36, -0.49) for the regression of gestation length against conception date, with indications of a significant hind genotype effect favouring shorter overall gestation lengths for crossbred hinds. Other effects for hind age, calf sex, birth weight, sire genotype and year were not significant. In Study 2, in which conception dates were artificially induced, there was a highly significant negative slope (-0.19), with a notable but non-significant effect of hind age favouring shorter overall gestation length for primiparous (pubertal) hinds (P>0.05). Other effects for hind live weight, calf sex and calf birth weight were not significant. All data sets support the hypothesis, and indicate that for every 10 days difference in conception date there was a change in gestation length of 1.9-4.9 days. This hints at the adaptive importance of optimisation of birth date in wild populations of red deer but the precise physiological mechanisms remain to be resolved. It is postulated that variation in fetal age during the latter stages of pregnancy, when feed quality and voluntary feed intake cycles are in a state of flux, may drive differential growth trajectories for early and late conceived fetuses, leading to nutritional control over fetal maturation and induction of parturition. However, consideration is also given to a putative direct effect of prevailing photoperiod on control of parturition processes in red deer.


Assuntos
Cervos/fisiologia , Fertilização/fisiologia , Prenhez/fisiologia , Animais , Animais Domésticos/fisiologia , Animais Selvagens/fisiologia , Ecossistema , Meio Ambiente , Estro , Feminino , Desenvolvimento Fetal , Feto/anatomia & histologia , Feto/fisiologia , Genótipo , Masculino , Gravidez , Prenhez/genética , Análise de Regressão , Fatores de Tempo
12.
Anim Reprod Sci ; 90(3-4): 287-306, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16298276

RESUMO

Low reproductive productivity of young red deer (Cervus elaphus) hinds on New Zealand deer farms appears to reflect high incidences of puberty failure at 16 months of age. This is despite the general attainment of average liveweights 15-25 kg in excess of the accepted minimum threshold for puberty in subspecies of western European origin (scoticus, elaphus and hippelaphus) that form the basis of the national herd. The present study tests the hypotheses that introgression of the larger North American wapiti subspecies (nelsoni, manitobensis and roosevelti) into breeding herds (1) can be assessed from morphological features of individuals, (2) that there is a relationship between the level of wapiti parentage and non-pregnancy rate at 18 months of age (a proxy for puberty failure) and (3) that minimum liveweight thresholds for puberty increase with increasing levels of wapiti parentage. A total of 4329 18-month-old hinds across four "red" deer farms in southern New Zealand were scanned for pregnancy status. Each hind was assigned a wapiti score (WS) as a subjective assessment of the obviousness of wapiti features. Various body measurements were additionally recorded for each hind. A hair sample was collected for DNA analysis (14 markers) to objectively assign subspecies pedigree (i.e. "Elkmeter") on a subset of 1258 individuals. A total of 506 (11.7%) hinds were not pregnant at 18 months of age with rates varying between 4.1 and 37.3% between farms and years. Mean WS differed significantly between farms and reflected the genetic management policy of each farm. WS was positively correlated to Elkmeter for each farm/year (<0.05) although regression slopes varied significantly. WS was able to be adjusted for these differences to assign a corrected WS (CWS) for all 4329 individuals that estimated the proportion wapiti parentage. Discriminant analysis of morphological variables relative to Elkmeter supported the first hypothesis and showed that shoulder height and body length were good indicators of the degree of wapiti parentage within individuals. This enabled the development of an objective estimate of wapiti parentage (EWP). The actual level of such parentage within herds ranged from <5 to >55%. There was a significant negative association between wapiti parentage and pregnancy, which was strongly influenced by liveweight, supporting the second and third hypotheses. This was manifest as marked displacement of pregnancy probability curves in relation to liveweight between genotype groups, particularly for those groups with >20% wapiti parentage. For example, predicted threshold liveweights required to achieve a 90% pregnancy rate for EWP values that represent 0, 10, 20, 30, 40 and 50% wapiti parentage were 81, 81, 85, 106, 127 and approximately 137 kg, respectively. Within the study herds, the majority of hinds of 0-20% wapiti parentage exceeded the predicted 90% threshold liveweights for their genotype cohort. However, hinds with higher levels of wapiti parentage generally fell below the predicted threshold for their genotype group. The data strongly suggest that under liveweight performance levels measured for red deer, hinds with >20% wapiti parentage are at high risk of puberty failure.


Assuntos
Cervos/genética , Cervos/fisiologia , Reprodução/genética , Reprodução/fisiologia , Maturidade Sexual , Envelhecimento , Animais , Biometria , Cruzamento , DNA/análise , Feminino , Genótipo , Cabelo , Nova Zelândia , Linhagem , Gravidez
13.
Anim Reprod Sci ; 86(3-4): 261-83, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15766805

RESUMO

The present study aimed to relate feed intake of red deer hinds during late pregnancy to dam body condition, foetal development and calf growth. Across 3 years, multiparous (n=33) or primiparous (n=18) hinds with known conception dates were housed in individual pens from days 150-220 of pregnancy, during which time they were each offered one of three daily allowances of pelletised rations (11 MJME/kg DM; 16% CP): high (H; ad libitum), medium (M; approximately 30% less; multiparous hinds only) and low (L; approximately 50% less). Restricted intake levels were retrospectively calculated from the mean intake of H hinds in the previous week. Hinds were returned to pasture at day 220 and calving was closely monitored. Liveweights, body condition score (BCS), and lactation score (LS) of hinds were recorded weekly from day 130 of pregnancy until calves were weaned at 12 weeks of age. Calves were tagged and weighed at birth, and subsequently weighed at 7 and 12 weeks of age. Additionally, hinds in the first year of study underwent CT scans on days 150 and 215 of pregnancy to assess compositional changes of the dam and conceptus. Mean daily ad libitum intakes of H hinds increased from 1.8 to 2.0 kg DM (0.6-0.7 MJME/kg0.75) at around day 150 to 2.8-3.2 kg DM (0.8-0.9 MJME/kg0.75) by day 220. Those of M and L hinds peaked at 1.8 and 1.6 kg DM, respectively, by day 220. This was reflected in significant treatment effects on liveweight gain and change in BCS and LS by the time of calving. CT scans indicated a significant treatment effect by day 215 on the mass of hind tissues (fat and lean) and a non-significant trend on conceptus/foetal weights. Despite apparent differences in foetal growth trajectories, there were no discernable treatment effects on sex-adjusted birth weights. However, there was an unexpectedly wide spread in calving dates that reflected considerable variation in gestation length. Furthermore, gestation length was negatively correlated with change in hind liveweight (but not BCS) between days 150 and 220 of pregnancy for all groups of hinds (P<0.05). Of three neonatal calf mortalities, none were related to overweight (dystocia) or underweight (non-viability) calves. Subsequent growth rates (g/day) of surviving calves did not reflect prior treatment of their dams, although variation in birth date influenced weights on specific dates. It is concluded from this study that while variation in nutrition to hinds during the last trimester may strongly influence foetal development, under conditions of modest feed imbalance, variation in gestation length compensates to ensure optimisation of birth weight.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Cervos/fisiologia , Paridade , Reprodução/fisiologia , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Peso ao Nascer , Composição Corporal , Peso Corporal , Ingestão de Alimentos , Sincronização do Estro , Feminino , Desenvolvimento Fetal , Idade Gestacional , Lactação/fisiologia , Gravidez , Tomografia Computadorizada por Raios X/veterinária , Desmame
14.
Anim Reprod Sci ; 86(3-4): 285-96, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15766806

RESUMO

The present study aimed to relate feed intake of red deer hinds in the later stages of gestating wapitixred deer crossbred foetuses on dam body condition, gestation length, birth weight and calf growth. Multiparous hinds (N=18) conceiving at known dates to either wapiti (n=12) or red deer (n=6) sires were housed in individual pens from days 150-220 of pregnancy, during which time they were offered either ad libitum access to pelletised rations (n=6 crossbred-bearing hinds [HH] and n=6 red deer-bearing hinds [RH]) or a restricted offer (n=6 crossbred-bearing hinds [HL]) set at 70% of the average ad libitum intake of HH hind in the previous week. Hinds were returned to pasture at day 220 and calving was closely monitored. Liveweights, body condition score (BCS), and lactation score (LS) of hinds were recorded weekly from day 130 of pregnancy until calves were weaned at 12 weeks of age. Calves were tagged and weighed at birth, and subsequently weighed at 7 and 12 weeks of age. HH and RH hinds exhibited similar patterns and levels of MEI/kg0.75, which peaked at 7.8 MJME/kg0.75 at day 220. HL hinds peaked at approximately 5 MJME/kg0.75 and showed significantly lower rates of liveweight gain during pregnancy. Interestingly, both crossbred-bearing groups initiated mammary development in advance of the RH hinds. While there were significant effects of foetal genotype on mean gestation length (239 days versus 234 days for crossbred versus red deer) and mean birth weight (14.5 kg versus 10 kg), the nutritional contrast for gestation length of crossbred-bearing hinds (i.e. HH versus HL) was not significant but approached significance for birth weight (14.5 kg versus 11.9 kg; P=0.06). Regression analysis revealed weak relationships between changes in hind liveweight and gestation length (P>0.05) but a significant relationship with birth weight (P<0.05). However, change in hind BCS was significantly related to both gestation length and birth weight. Crossbred calves reared by HH hinds were 30% heavier at 7 and 12 weeks of age than the red deer calves. However, those reared by HL hinds were significantly lighter than their genotype contemporaries and only marginally heavier than the red deer calves. These results generally contrast with the previous studies on red deer hinds gestating red deer foetuses [Asher, G.W., Mulley, R.C., O'Neill, K.T., Scott, I.C., Jopson, N.B., Littlejohn, R. 2004. Influence of level of nutrition during late pregnancy on reproductive productivity of red deer, (1) Adult and primiparous hinds gestating red deer calves. Anim. Reprod. Sci., in press] and indicate that the genetically determined higher growth requirements of crossbred foetuses may override any mechanism of compensatory control of gestation length at the expense of calf birth weight. Furthermore, there were marked carryover effects of late gestational feeding on crossbred calf growth and their dam's BCS that highlight the high nutritional demands of lactation.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Cruzamentos Genéticos , Cervos/fisiologia , Reprodução/fisiologia , Envelhecimento , Animais , Peso ao Nascer , Composição Corporal , Cruzamento , Ingestão de Alimentos , Feminino , Idade Gestacional , Lactação , Masculino , Gravidez , Análise de Regressão , Fatores de Tempo , Desmame , Aumento de Peso
15.
J Biol Chem ; 276(25): 22537-43, 2001 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-11313359

RESUMO

Lysyl oxidase catalyzes the final enzymatic step required for collagen and elastin cross-linking in extracellular matrix biosynthesis. Pro-lysyl oxidase is processed by procollagen C-proteinase activity, which also removes the C-propeptides of procollagens I-III. The Bmp1 gene encodes two procollagen C-proteinases: bone morphogenetic protein 1 (BMP-1) and mammalian Tolloid (mTLD). Mammalian Tolloid-like (mTLL)-1 and -2 are two genetically distinct BMP-1-related proteinases, and mTLL-1 has been shown to have procollagen C-proteinase activity. The present study is the first to directly compare pro-lysyl oxidase processing by these four related proteinases. In vitro assays with purified recombinant enzymes show that all four proteinases productively cleave pro-lysyl oxidase at the correct physiological site but that BMP-1 is 3-, 15-, and 20-fold more efficient than mTLL-1, mTLL-2, and mTLD, respectively. To more directly assess the roles of BMP-1 and mTLL-1 in lysyl oxidase activation by connective tissue cells, fibroblasts cultured from Bmp1-null, Tll1-null, and Bmp1/Tll1 double null mouse embryos, thus lacking BMP-1/mTLD, mTLL-1, or all three enzymes, respectively, were assayed for lysyl oxidase enzyme activity and for accumulation of pro-lysyl oxidase and mature approximately 30-kDa lysyl oxidase. Wild type cells or cells singly null for Bmp1 or Tll1 all produced both pro-lysyl oxidase and processed lysyl oxidase at similar levels, indicating apparently normal levels of processing, consistent with enzyme activity data. In contrast, double null Bmp1/Tll1 cells produced predominantly unprocessed 50-kDa pro-lysyl oxidase and had lysyl oxidase enzyme activity diminished by 70% compared with wild type, Bmp1-null, and Tll1-null cells. Thus, the combination of BMP-1/mTLD and mTLL-1 is shown to be responsible for the majority of processing leading to activation of lysyl oxidase by murine embryonic fibroblasts, whereas in vitro studies identify pro-lysyl oxidase as the first known substrate for mTLL-2.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Embrião de Mamíferos/enzimologia , Precursores Enzimáticos/metabolismo , Metaloendopeptidases/metabolismo , Processamento de Proteína Pós-Traducional , Proteína-Lisina 6-Oxidase/metabolismo , Animais , Proteína Morfogenética Óssea 1 , Células Cultivadas , Embrião de Mamíferos/citologia , Ativação Enzimática , Fibroblastos/citologia , Fibroblastos/enzimologia , Humanos , Camundongos , Proteínas Recombinantes/metabolismo
16.
Nature ; 410(6827): 475-8, 2001 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-11260715

RESUMO

Twisted gastrulation (TSG) is involved in specifying the dorsal-most cell fate in Drosophila embryos, but its mechanism of action is poorly understood. TSG has been proposed to modify the action of Short gastrulation (SOG), thereby increasing signalling by the bone morphogenetic protein (BMP) Decapentaplegic. SOG, an inhibitor of BMP signalling, is in turn inactivated by the protease Tolloid. Here we identify Tsg gene products from human, mouse, Xenopus, zebrafish and chick. Expression patterns in mouse and Xenopus embryos are consistent with in vivo interactions between Tsg, BMPs and the vertebrate SOG orthologue, chordin. We show that Tsg binds both the vertebrate Decapentaplegic orthologue BMP4 and chordin, and that these interactions have multiple effects. Tsg increases chordin's binding of BMP4, potentiates chordin's ability to induce secondary axes in Xenopus embryos, and enhances chordin cleavage by vertebrate tolloid-related proteases at a site poorly used in Tsg's absence; also, the presence of Tsg enhances the secondary axis-inducing activity of two products of chordin cleavage. We conclude that Tsg acts as a cofactor in chordin's antagonism of BMP signalling.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas de Drosophila , Gástrula/metabolismo , Glicoproteínas , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas/metabolismo , Proteínas/fisiologia , Transdução de Sinais , Sequência de Aminoácidos , Animais , Proteína Morfogenética Óssea 4 , Proteínas Morfogenéticas Ósseas/antagonistas & inibidores , Embrião de Galinha , Mapeamento Cromossômico , Cromossomos Humanos Par 18 , Perfilação da Expressão Gênica , Humanos , Camundongos , Dados de Sequência Molecular , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , Proteínas/química , Proteínas/genética , Proteínas Recombinantes/metabolismo , Xenopus , Proteínas de Xenopus , Peixe-Zebra , Proteínas de Peixe-Zebra
17.
J Biol Chem ; 275(39): 30504-11, 2000 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-10896944

RESUMO

Bone morphogenetic protein-1 (BMP-1) is a metalloprotease that plays important roles in regulating the deposition of fibrous extracellular matrix in vertebrates, including provision of the procollagen C-proteinase activity that processes the major fibrillar collagens I-III. Biglycan, a small leucine-rich proteoglycan, is a nonfibrillar extracellular matrix component with functions that include the positive regulation of bone formation. Biglycan is synthesized as a precursor with an NH(2)-terminal propeptide that is cleaved to yield the mature form found in vertebrate tissues. Here, we show that BMP-1 cleaves probiglycan at a single site, removing the propeptide and producing a biglycan molecule with an NH(2) terminus identical to that of the mature form found in tissues. BMP-1-related proteases mammalian Tolloid and mammalian Tolloid-like 1 (mTLL-1) are shown to have low but detectable levels of probiglycan-cleaving activity. Comparison shows that wild type mouse embryo fibroblasts (MEFs) produce only fully processed biglycan, whereas MEFs derived from embryos homozygous null for the Bmp1 gene, which encodes both BMP-1 and mammalian Tolloid, produce predominantly unprocessed probiglycan, and MEFs homozygous null for both the Bmp1 gene and the mTLL-1 gene Tll1 produce only unprocessed probiglycan. Thus, all detectable probiglycan-processing activity in MEFs is accounted for by the products of these two genes.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Metaloendopeptidases/metabolismo , Precursores de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Proteoglicanas/metabolismo , Animais , Biglicano , Proteína Morfogenética Óssea 1 , Decorina , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular , Homozigoto , Humanos , Metaloproteases , Camundongos , Camundongos Mutantes , Precursores de Proteínas/genética , Proteínas/genética , Proteínas/metabolismo , Proteoglicanas/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Metaloproteases Semelhantes a Toloide
18.
Anim Reprod Sci ; 59(1-2): 43-59, 2000 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-10804275

RESUMO

This study compared the onset and duration of the breeding season of female red deer (Cervus elaphus scoticus) and its hybrids with either wapiti (Cervus elaphus nelsoni) or Père David's (PD) deer (Elaphurus davidianus). In Trial 1 (1995), adult red deer (n=9), F1 hybrid wapiti x red deer (n=6) and maternal backcross hybrid PD deer x red deer (i.e., 14 PD; n=9) were maintained together in the presence of a vasectomised red deer stag for 12 months. They were blood-sampled daily or three times weekly so that concentration profiles of plasma progesterone could be used to identify the initiation, duration and cessation of luteal events. There was clear evidence of luteal cyclicity between April and September, with the transition into breeding associated with an apparent silent ovulation and short-lived corpus luteum (i.e., 6-12 days) in every hind. A significant genotype effect occurred in the mean time to first oestrus (P<0.05), with wapiti hybrids and 14 PD hybrids being 9 and 5 days earlier than red deer. Between six and nine oestrous cycles were exhibited by each hind, with no difference in mean cycle length (19.5-19.6 days) between genotypes (P0.10). The overall length of the breeding season was significantly longer for wapiti hybrids (143 days) than for either red deer (130 days) and 14 PD hybrids (132 days, P<0.05). In Trial 2 (1998), adult red deer (n=5), 14 PD hybrids (n=5) and F(1) PD x red deer hybrid (n=5) hinds were maintained together from mid-February (late anoestrus) to early May, in the presence of a fertile red deer stag from 1 April. Thrice-weekly blood sampling yielded plasma progesterone profiles indicative of the onset of the breeding season. Again, there was a significant genotype effect on the mean time to first oestrus (P<0. 05), with F(1) PD hybrids and 14 PD hybrids being 13 and 5 days earlier than red deer. However, conception dates were influenced by the timing of stag joining, and were not significantly different between genotypes. The results indicate genetic effects on reproductive seasonality. However, seasonality observed for PD x red deer hybrids more closely approximated that of red deer than PD deer.


Assuntos
Cervos/genética , Fase Luteal/genética , Reprodução/genética , Estações do Ano , Animais , Cervos/sangue , Feminino , Genótipo , Progesterona/sangue , Prolactina/sangue , Radioimunoensaio/veterinária
19.
Anim Reprod Sci ; 59(1-2): 61-70, 2000 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-10804276

RESUMO

This study evaluated the influences of seasons and genotype on the superovulatory response to a standardised oFSH regimen in red deer (Cervus elaphus scoticus) and its hybrids with either wapiti (C.e. nelsoni) or Père David's (PD) deer (Elaphurus davidianus). Adult red deer (n=9), F(1) hybrid wapiti x red deer (n=6), and maternal backcross hybrid PD x red deer (i.e., 14 PD hybrid; n=9) were kept together in the presence of a vasectomised stag for 13 months. At 6 weekly intervals, all hinds received a standardised treatment regimen used routinely to induce a superovulatory response in red deer hinds, with 10 consecutive treatments spanning an entire year. This involved synchronisation with intravaginal progesterone devices and delivery of multiple injections of oFSH (equivalent to 72 units NIH-FSH-S(1)). Laparoscopy to assess ovarian response was performed 6-7 days after the removal of the devices. Both season and genotype had significant effects on ovulation rate (OR) and total follicular stimulation (TFS) (P<0.05). For all the three genotypes, ovarian responses were highest from March to November (breeding season) and lowest in the period from December to January, inclusive. Mean OR for red deer hinds ranged from 3.7 to 1.8 during the breeding season, with no observable trend. All red deer hinds were anovulatory during December and January. A similar pattern occurred for 14 PD hybrids, although mean OR during the breeding seasons were twofold lower than for the red deer. For F(1) wapiti hybrids, the first two treatments in March and April resulted in the highest mean OR observed (15.6 and 11.7, respectively). Thereafter, mean values ranged between 6.3 and 4.7 for the remainder of the breeding season. Furthermore, mean OR of 3.0 and 0.5 were recorded in December and January, respectively. For the red deer and F(1) wapiti hybrids, between-hind variation in OR was not randomly distributed across the treatment dates, indicating that the individuals varied significantly in their ability to respond to oFSH, at least within a given season.In conclusion, the study has shown that relative to red deer, F(1) wapiti hybrid hinds exhibit a higher sensitivity to oFSH, whereas 14 PD hybrid hinds have a lower sensitivity. However, individual variation within genotype was very marked. A seasonal effect was apparent for all genotypes, although some F(1) wapiti hybrid hinds exhibited ovulatory responses throughout the year.


Assuntos
Cervos/genética , Hormônio Foliculoestimulante/farmacologia , Estações do Ano , Superovulação/efeitos dos fármacos , Superovulação/genética , Administração Intravaginal , Criação de Animais Domésticos , Animais , Feminino , Genótipo , Progesterona/administração & dosagem , Progesterona/farmacologia
20.
J Biol Chem ; 275(30): 22728-35, 2000 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-10806203

RESUMO

Epithelial cells maintained in culture medium containing low calcium proteolytically process laminin 5 (alpha3beta3gamma2) within the alpha3 and gamma2 chains (). Experiments were designed to identify the enzyme(s) responsible for the laminin 5 processing and the sites of proteolytic cleavage. To characterize the nature of laminin 5 processing, we determined the N-terminal amino acid sequences of the proteolytic fragments produced by the processing events. The results indicate that the first alpha3 chain cleavage (200-l65 kDa alpha3) occurs within subdomain G4 of the G domain. The second cleavage (l65-l45 kDa alpha3) occurs within the lIla domain, 11 residues N-terminal to the start of domain II. The gamma chain is cleaved within the second epidermal growth factor-like repeat of domain Ill. The sequence cleaved within the gamma2 chain matches the consensus sequence for the cleavage of type I, II, and III procollagens by bone morphogenetic protein-1 (BMP-1), also known as type I procollagen C-proteinase (). Recombinant BMP-1 cleaves gamma2 in vitro, both within intact laminin 5 and at the predicted site of a recombinant gamma2 short arm. alpha3 is also cleaved by BMP-1 in vitro, but the cleavage site is yet to be determined. These results show the laminin alpha3 and gamma2 chains to be substrates for BMP-1 in vitro. We speculate that gamma2 cleavage is required for formation of the laminin 5-6 complex and that this complex is directly involved in assembly of the interhemidesmosomal basement membrane. This further suggests that BMP-1 activity facilitates basement membrane assembly, but not hemidesmosome assembly, in the laminin 5-rich dermal-epidermal junction basement membrane in vivo.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Laminina/metabolismo , Metaloendopeptidases/metabolismo , Processamento de Proteína Pós-Traducional , Animais , Sequência de Bases , Proteína Morfogenética Óssea 1 , Bovinos , Células Cultivadas , Primers do DNA , Humanos , Hidrólise , Queratinócitos/citologia , Queratinócitos/metabolismo , Ligação Proteica , Proteínas Recombinantes/metabolismo
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