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1.
Sci Rep ; 12(1): 728, 2022 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-35031666

RESUMO

Quantifying the drivers of population size in reef sharks is critical for the development of appropriate conservation strategies. In north-west Australia, shark populations inhabit coral reefs that border growing centres of human population, industry, and tourism. However, we lack baseline data on reef sharks at large spatial scales (hundreds of km) that might enable managers to assess the status of shark populations in the face of future development in this region. Here, we examined the occurrence, abundance and behaviour of apex (Galeocerdo cuvier, Carcharhinus plumbeus) and reef (C. amblyrhynchos, C. melanopterus, Triaenodon obesus) sharks using > 1200 deployments of baited remote underwater stereo-video systems (stereo-BRUVs) across > 500 km of coastline. We found evidence for species-specific influences of habitat and fishing activities on the occurrence (probability of observation), abundance (MaxN) and behaviour of sharks (time of arrival to the stereo-BRUVs and likelihood of feeding). Although the presence of management zoning (No-take areas) made little difference to most species, C. amblyrhynchos were more common further from boat ramps (a proxy of recreational fishing pressure). Time of arrival for all species was also influenced by distance to boat ramp, although patterns varied among species. Our results demonstrate the capacity for behavioural metrics to complement existing measures of occurrence and abundance in assessing the potential impact of human activities on shark populations.


Assuntos
Comportamento Animal , Conservação dos Recursos Naturais , Recifes de Corais , Ecossistema , Densidade Demográfica , Tubarões/fisiologia , Animais , Austrália , Atividades Humanas , Humanos , Especificidade da Espécie
2.
J Assist Reprod Genet ; 36(1): 29-38, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30232643

RESUMO

PURPOSE: The objective was to investigate if the gonadotropin receptor variants N680S (N: asparagine, S: serine, rs6166) in the follicle-stimulating hormone receptor (FSHR) and N312S (rs2293275) in the luteinizing hormone/human chorionic gonadotropin receptor (LHCGR) predicted cumulative live birth rate after in vitro fertilization (IVF). METHODS: A total of 665 women were consecutively enrolled for IVF during the period 2007-2016. Inclusion criteria were < 40 years of age, body mass index < 30 kg/m2, non-smoking, regular menstruation cycle of 21-35 days, and bilateral ovaries. A blood sample was drawn for endocrine hormonal analysis and for DNA extraction with subsequent genotyping of the FSHR N680S and LHCGR N312S polymorphisms. Statistical analyses were done on all completed IVF cycles. RESULTS: Women homozygous for S in both receptors combined (4S) had significantly higher live birth rate compared to those with other receptor variants when combining the first three IVF cycles (OR = 2.00, 95% CI [1.02, 3.92], p = 0.043). Cumulatively higher chance of live birth rate, during all IVF cycles, was also evident (HR = 1.89, 95% CI [1.00, 3.57], p = 0.049). CONCLUSIONS: Gonadotropin receptor variants are promising candidates for the prediction of the possibility to have a baby to take home after IVF treatment.


Assuntos
Coeficiente de Natalidade , Fertilização in vitro , Polimorfismo Genético , Receptores do FSH/genética , Receptores do LH/genética , Adulto , Feminino , Humanos , Nascido Vivo , Gravidez , Taxa de Gravidez , Resultado do Tratamento
3.
Hum Reprod ; 31(3): 672-83, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26769719

RESUMO

STUDY QUESTION: Can gonadotrophin receptor variants separately or in combination, be used for the prediction of pregnancy chances in in vitro fertilization (IVF) trials? SUMMARY ANSWER: The luteinizing hormone/human chorionic gonadotrophin receptor (LHCGR) variant N312S and the follicle-stimulating hormone receptor (FSHR) variant N680S can be utilized for the prediction of pregnancy chances in women undergoing IVF. WHAT IS KNOWN ALREADY: The FSHR N680S polymorphism has been shown to affect the ovarian response in response to gonadotrophin treatment, while no information is currently available regarding variants of the LHCGR in this context. STUDY DESIGN, SIZE, DURATION: Cross-sectional study, duration from September 2010 to February 2015. Women undergoing IVF were consecutively enrolled and genetic variants compared between those who became pregnant and those who did not. The study was subsequently replicated in an independent sample. Granulosa cells from a subset of women were investigated regarding functionality of the genetic variants. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women undergoing IVF (n = 384) were enrolled in the study and genotyped. Clinical variables were retrieved from medical records. For replication, an additional group of n = 233 women was utilized. Granulosa cells from n = 135 women were isolated by flow cytometry, stimulated with Follitropin alpha or Menotropin, and the downstream targets 3',5'-cyclic adenosine monophosphate (cAMP) and inositol 1,4,5-trisphosphate (IP3) measured with enzyme-linked immunosorbent assay. MAIN RESULTS AND THE ROLE OF CHANCE: Women homozygous for serine (S) in both polymorphisms displayed higher pregnancy rates than women homozygous asparagine (N) (OR = 14.4, 95% CI: [1.65, 126], P = 0.016). Higher pregnancy rates were also evident for women carrying LHCGR S312, regardless of FSHR variant (OR = 1.61, 95% CI: [1.13, 2.29], P = 0.008). These women required higher doses of FSH for follicle recruitment than women homozygous N (161 versus 148 IU, P = 0.030). When combining the study cohort with the replication cohort (n = 606), even stronger associations with pregnancy rates were noted for the combined genotypes (OR = 11.5, 95% CI: [1.86, 71.0], P = 0.009) and for women carrying LHCGR S312 (OR = 1.49, 95% CI: [1.14, 1.96], P = 0.004). A linear significant trend with pregnancy rate and increasing number of G alleles was also evident in the merged study population (OR = 1.34, 95% CI: [1.10, 1.64], P = 0.004). A lower cAMP response in granulosa cells was noted following Follitropin alpha stimulation for women homozygous N in both polymorphisms, compared with women with other genotypes (0.901 pmol cAMP/mg total protein versus 2.19 pmol cAMP/mg total protein, P = 0.035). LIMITATIONS, REASONS FOR CAUTION: Due to racial differences in LHCGR genotype distribution, these results may not be applicable for all populations. WIDER IMPLICATIONS OF THE FINDINGS: Despite that >250 000 cycles of gonadotrophin stimulations are performed annually worldwide prior to IVF, it has not been possible to predict neither the pregnancy outcome, nor the response to the hormone with accuracy. If LHCGR and FSHR variants are recognized as biomarkers for chance of pregnancy, more individualized and thereby more efficient treatment modalities can be developed. STUDY FUNDING, COMPETING INTERESTS: This work was supported by Interreg IV A, EU (grant 167158) and ALF governments grant (F2014/354). Merck-Serono (Darmstadt, Germany) supported the enrollment of the subjects. The authors declare no conflict of interest.


Assuntos
Fertilização in vitro , Polimorfismo Genético , Receptores do FSH/genética , Receptores do LH/genética , Estudos de Coortes , Estudos Transversais , Feminino , Genótipo , Humanos , Gravidez , Taxa de Gravidez , Resultado do Tratamento
4.
Mol Hum Reprod ; 21(3): 255-61, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25403644

RESUMO

The most pronounced effects of FSH signalling are potentially displayed in the follicle fluid, which acts as a reservoir for FSH-induced granulosa cell (GC) secreted hormones. This study investigates the effects of two common polymorphisms of FSHR, FSHR 307 (rs6165) and FSHR 680 (rs6166), by evaluating the hormone and gene expression profiles of human small antral follicles collected under physiological conditions in connection with fertility preservation. In total 69 women at various time during the menstrual cycle were included in this study. The intrafollicular hormone content of 179 follicular fluid samples and the gene expression levels of 85 GC samples were correlated to the genotype of both FSHR polymorphisms. The following parameters were evaluated: follicle diameter, levels of Anti-Müllerian hormone (AMH), progesterone, estradiol, testosterone and androstenedione and gene expression levels of FSHR, luteinizing hormone receptor (LHR), androgen receptor, aromatase cytochrome p450 (CYP19A1), AMH and AMH receptor II (AMHR2). There was 100% concordance between the FSHR 307 and the FSHR 680 genotypes: A/A (p.307Thr/Thr and p.680Asn/Asn), A/G (p.307Thr/Ala and p.680Asn/Ser) and G/G (p.307Ala/Ala and p.680Ser/Ser). Considering all follicles, compared with the other genotypes the G/G genotype was associated with significantly elevated gene expression levels for LHR, while AMHR2 gene expression levels were significantly reduced. In follicles 3-6 mm in diameter LHR gene expression was significantly increased, whereas AMH gene expression was significantly reduced for the G/G genotype. In follicles >6 mm, estradiol and CYP19A1 gene expression levels were significantly higher for the G/G genotype. In conclusion, significant changes were observed between the FSHR 307/680 polymorphisms in human small antral follicles collected under physiological FSH conditions.


Assuntos
Líquido Folicular/metabolismo , Regulação da Expressão Gênica , Hormônios Gonadais/genética , Células da Granulosa/metabolismo , Polimorfismo de Nucleotídeo Único , Receptores do FSH/genética , Adolescente , Adulto , Androstenodiona/metabolismo , Hormônio Antimülleriano/genética , Hormônio Antimülleriano/metabolismo , Aromatase/genética , Aromatase/metabolismo , Tamanho Celular , Estradiol/metabolismo , Feminino , Líquido Folicular/química , Perfilação da Expressão Gênica , Genótipo , Hormônios Gonadais/metabolismo , Células da Granulosa/citologia , Humanos , Ciclo Menstrual/fisiologia , Progesterona/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Receptores do FSH/metabolismo , Receptores do LH/genética , Receptores do LH/metabolismo , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Testosterona/metabolismo
5.
Am J Physiol Regul Integr Comp Physiol ; 305(10): R1093-101, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24089370

RESUMO

Prenatal hypoxia leads to an increased risk of adult cardiovascular disease. We have previously demonstrated a programming effect of prenatal hypoxia on the cardiac ß-adrenergic (ßAR) response. The aim of this study was to determine 1) whether the decrease in ßAR sensitivity in prenatally hypoxic 5-wk old chicken hearts is linked to changes in ß1AR/ß2ARs, Gαi expression and cAMP accumulation and 2) whether prenatal hypoxia has an effect on heart function in vivo. We incubated eggs in normoxia (N, 21% O2) or hypoxia from day 0 (H, 14% O2) and raised the posthatchlings to 5 wk of age. Cardiac ß1AR/ß2ARs were assessed through competitive binding of [(3)H]CGP-12177 with specific ß1AR or ß2AR blockers. Gαs and Gαi proteins were assessed by Western blot and cAMP accumulation by ELISA. Echocardiograms were recorded in anesthetized birds to evaluate diastolic/systolic diameter and heart rate and tissue sections were stained for collagen. We found an increase in relative heart mass, ß1ARs, and Gαs in prenatally hypoxic hearts. cAMP levels after isoproterenol stimulation and collagen content was not changed in H compared with N, but in vivo echocardiograms showed systolic contractile dysfunction. The changes in ßAR and G protein subtypes may be indicative of an early compensatory stage in the progression of cardiac dysfunction, further supported by the cardiac hypertrophy and systolic contractile dysfunction. We suggest that it is not the changes in the proximal part of the ßAR system that causes the decreased cardiac contractility, but Ca(2+) handling mechanisms further downstream in the ßAR signaling cascade.


Assuntos
Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Oxigênio/metabolismo , Receptores Adrenérgicos beta/metabolismo , Transdução de Sinais/fisiologia , Antagonistas Adrenérgicos beta , Animais , Metabolismo Basal , Embrião de Galinha , AMP Cíclico/metabolismo , Fibrose/etiologia , Fibrose/veterinária , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Cardiopatias/etiologia , Hipóxia , Receptores Adrenérgicos beta/genética
6.
Poult Sci ; 90(1): 126-35, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21177452

RESUMO

Genetic selection programs have imposed large phenotypic changes in domesticated chicken breeds that are also apparent during embryonic development. Broilers, for example, have a faster growth rate before hatching in comparison with White Leghorns, indicating that the allocation of resources toward different functions already begins before hatching. Therefore, we hypothesized that embryonic organ growth would follow different developmental trajectories and would be differentially affected by an oxygen shortage during incubation. Heart, brain, and liver growth were studied in broiler, White Leghorn, and Red Junglefowl embryos at embryonic (E) ages E11, E13, E15, E18, and E20, and the results were fitted to growth allometric equations to determine the degree of organ stunting or sparing caused by low oxygen during incubation. Hypoxia caused a 3-fold larger mortality in Red Junglefowl than in the domesticated breeds, with a similar impairment of embryonic growth of 18%, coupled with a reduction in yolk utilization of 56%. Relative brain size was not affected by hypoxia in any breed, but a substantial stunting effect was observed for the liver and heart at late embryonic ages, with marked differences between breeds. In Red Junglefowl, only the heart was stunted. In White Leghorns, only the liver was stunted, and in broilers, both organs were stunted. These results can be explained in terms of the selection pressure on long-term production traits (reproductive effort) in White Leghorns, requiring a more efficient lipid metabolism, compared with the selection pressure on shorter-term production traits (growth) in broilers, requiring overall metabolic turnover and convective nutrient delivery to all tissues. At the same time, a remarkable sparing of the heart was observed in broilers and Red Junglefowl between E11 and E15, which suggests that cardiac growth can be manipulated during embryonic development. This result could be relevant for manipulating the phenotype of the heart for management purposes at a developmental stage when the bird is most versatile and phenotypically malleable.


Assuntos
Galinhas/crescimento & desenvolvimento , Galinhas/genética , Desenvolvimento Embrionário/genética , Óvulo/crescimento & desenvolvimento , Oxigênio/farmacologia , Animais , Animais Domésticos , Encéfalo/crescimento & desenvolvimento , Embrião de Galinha/fisiologia , Relação Dose-Resposta a Droga , Gema de Ovo , Desenvolvimento Embrionário/efeitos dos fármacos , Hipóxia , Fígado/crescimento & desenvolvimento
7.
J Physiol Pharmacol ; 61(5): 619-28, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21081806

RESUMO

The reactivity of human fetoplacental arteries is regulated by humoral and local factors of maternal and fetal origin. The chorioallantoic (CA) arteries of bird embryos are homologous to fetoplacental arteries and fulfill the same gas-exchange purpose without maternal influences, but their reactivity has not been studied in detail. In the present study we hypothesized that CA arteries would respond to vasoactive factors similarly to fetoplacental arteries and the response would change during development between maximal vascular CA expansion (15 of the 21 days incubation period) and prior to hatching. Therefore, we analyzed the reactivity of third order arteries (≈200 µm) from the CA membrane of 15 and 19 day chicken embryos. CA arteries contracted in response to K(+), the thromboxane A(2) mimetic U46619, endothelin-1, acetylcholine and acute hypoxia, but showed no reaction to α-adrenergic stimulation (phenylephrine). The nitric oxide donor sodium nitroprusside, the adenylyl cyclase agonist forskolin, and the ß-adrenergic agonist isoproterenol relaxed CA arteries pre-contracted with K(+) or U46619. The contraction evoked by acetylcholine and the relaxations evoked by sodium nitroprusside and isoproterenol decreased with incubation age. In conclusion, CA arteries share many characteristics with human fetoplacental arteries, such as pronounced relaxation to ß-adrenergic stimuli and hypoxic vasoconstriction. Our study will be the foundation for future studies to explain disparate and common responses of the CA and fetoplacental vasculature.


Assuntos
Artérias/fisiologia , Membrana Corioalantoide/irrigação sanguínea , Circulação Placentária/fisiologia , Vasoconstrição , Vasodilatação , Animais , Artérias/embriologia , Embrião de Galinha , Galinhas , Relação Dose-Resposta a Droga , Feminino , Humanos , Hipóxia/induzido quimicamente , Modelos Animais , Óxido Nítrico/metabolismo , Gravidez , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/administração & dosagem , Vasodilatação/efeitos dos fármacos , Vasodilatadores/administração & dosagem
8.
J Vet Dent ; 26(4): 213-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20192019

RESUMO

Several disturbances can occur in enamel formation. Amelogenesis imperfecta is an inherited enamel malformation that has not previously been reported in dogs. The aims of this study were to investigate amelogenesis imperfecta-like tooth discoloration in standard poodle dogs by histopathological characterization of discolored teeth from affected dogs, investigating whether these dogs have a common genetic background, and assessing how common this problem is in the breed. Histologically, a defect of enamel mineralization was documented. Affected enamel contained a large residual amount of organic matrix, showing that the enamel was not fully mineralized. In some sections, the enamel appeared intact, but with excessively well-defined enamel prisms which is an additional sign of poor mineralization. The abnormal enamel was identical to that seen in humans with amelogenesis imperfecta. Five of 27 standard poodle dogs present at a dog show had discolored teeth. A four-generation pedigree was available containing an example of parents also having discolored teeth one of which had amelogenesis imperfecta confirmed histologically. In all subsequent litters from these dogs, there was at least one dog with discolored teeth, and two histologically confirmed cases of amelogenesis imperfecta four generations later. Histological examination and the apparent familial occurrence indicates that amelogenesis imperfecta is a common cause of discolored teeth in standard poodle dogs in Sweden.


Assuntos
Amelogênese Imperfeita/veterinária , Doenças do Cão/genética , Amelogênese Imperfeita/genética , Amelogênese Imperfeita/patologia , Animais , Doenças do Cão/patologia , Cães , Feminino , Predisposição Genética para Doença , Masculino , Linhagem , Inquéritos e Questionários , Suécia
9.
J Neurol Neurosurg Psychiatry ; 77(5): 590-5, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16354737

RESUMO

OBJECTIVE: To determine prevalence and intensity of pain after stroke, focusing on patients' perspectives. METHODS: During a one year period, 416 first-ever stroke patients were included in the population based Lund Stroke Register. After 4 and 16 months (median), 297 patients (98% of survivors) were followed up. Worst pain intensity during the previous 48 hours was assessed on a visual analogue scale (VAS), range 0 to 100: a score of 0 to 30 was defined as no or mild pain; 40 to 100 as moderate to severe pain. NIH stroke scale (NIHSS) score and HbA1c were assessed at baseline. At 16 months, screening for depression was done using the geriatric depression scale (GDS-20), and cognition with the mini-mental state examination (MMSE). Predictors of pain were determined by multivariate analyses. RESULTS: Moderate to severe pain was reported by 96 patients (32%) after four months (VAS median=60). Predictors of pain were younger age (p=0.01), female sex (p=0.006), higher NIHSS score (p<0.001), and raised HbA1c (p=0.001) at stroke onset. At 16 months, only 62 patients (21%) had moderate to severe pain, but pain intensity was more severe (median VAS score=70; p<0.016). Higher pain intensity correlated with female sex, worse GDS-20 score, better MMSE score, and raised HbA1c. Pain was persistent in 47%, disturbed sleep in 58%, and required rest for relief in 40% of patients. CONCLUSIONS: Although prevalence of pain after stroke decreased with time, after 16 months 21% had moderate to severe pain. Late pain after stroke was on average more severe, and profoundly affected the patients' wellbeing.


Assuntos
Infarto Cerebral/epidemiologia , Medição da Dor , Dor/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infarto Cerebral/classificação , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Dor/classificação , Manejo da Dor , Fatores Sexuais , Resultado do Tratamento
10.
Ann Rheum Dis ; 59(3): 236-8, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10700436

RESUMO

This case report describes a young woman with systemic lupus erythematosus starting at 16 years of age and giving rise to severe neurological complications including bilateral opticus neuritis and transverse myelitis. Despite heavy immunosuppression her condition steadily aggravated. At this point it was decided to perform autologous stem cell transplantation. Haematopoietic stem cells were mobilised with cyclophosphamide and granulocyte colony stimulating factor. Enrichment of CD34(+)cells was followed by depletion of peripheral T and B cells. The post-transplantation course was uneventful, and all the neurological deficits improved promptly during the 15 months of follow up. This is the first description of successful autologous stem cell transplantation in a case of life threatening central nervous system lupus.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Vasculite Associada ao Lúpus do Sistema Nervoso Central/terapia , Adolescente , Feminino , Humanos , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico , Imageamento por Ressonância Magnética
12.
Phys Rev Lett ; 76(17): 3092-3095, 1996 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-10060873
14.
Phys Rev Lett ; 76(2): 204-207, 1996 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-10061042
19.
Neurology ; 43(11): 2189-92, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8232927

RESUMO

After obtaining informed consent, we randomized 78 patients with severe hemiparesis of the left or right side within 10 days of stroke onset: 40 to a control group receiving daily physiotherapy and occupational therapy, and 38 to a group that, in addition, we treated with sensory stimulation (acupuncture) twice a week for 10 weeks. The median age was 76 years for both groups. Motor function, balance, and ADL (Barthel's Index) were assessed before the start of treatment and at 1 and 3 months after stroke onset; ADL was also assessed after 12 months. We assessed the quality of life (QL) using the Nottingham Health Profile 3, 6, and 12 months after stroke onset. Patients given sensory stimulation recovered faster and to a larger extent than the controls, with a significant difference for balance, mobility, ADL, QL, and days spent at hospitals/nursing homes. Whether acupuncture per se is responsible for the differences requires further study.


Assuntos
Terapia por Acupuntura , Transtornos Cerebrovasculares/terapia , Atividades Cotidianas , Idoso , Transtornos Cerebrovasculares/complicações , Transtornos Cerebrovasculares/fisiopatologia , Feminino , Hemiplegia/etiologia , Humanos , Masculino , Movimento/fisiologia , Qualidade de Vida , Resultado do Tratamento
20.
Phys Rev A ; 48(4): 2772-2778, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9909926
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