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1.
Biol Lett ; 19(8): 20230312, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37643644

RESUMO

The Lower Devonian (Lower Emsian, -400 Myr) roof slates of the Hunsrück in southeastern Germany have delivered a highly diverse and exceptionally preserved marine fauna that provides a unique snapshot into the anatomy and ecology of a wide range of Palaeozoic animals. Several of the described taxa, however, remain enigmatic in their affinity, at least until new pyritized features hidden under the surface of the slate are revealed using X-ray radiography or micro-computed tomography (µCT). Here, we redescribe such an enigmatic fossil, the putative anostracan crustacean Gilsonicaris rhenanus Van Straelen, 1943. Using µCT scanning, we unveil unprecedented details of its anatomy, including a ventral oral opening and four pairs of recalcitrant jaw elements. These jaws are morphologically consistent with the scolecodonts of eunicidan polychaetes, which along with the gross anatomy of the body and head unambiguously identifies G. rhenanus as a polychaete rather than an arthropod. While this discovery firmly discards the Early Devonian record of crown anostracans in the fossil record, it adds a new record of eunicidan soft tissues, which are surprisingly rare considering the abundant microfossil record of scolecodonts.


Assuntos
Artrópodes , Crustáceos , Animais , Microtomografia por Raio-X , Ecologia , Fósseis
2.
Nat Ecol Evol ; 6(8): 1095-1104, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35879540

RESUMO

Cnidarians are a disparate and ancient phylum, encompassing corals and jellyfish, and occupy both the pelagic and benthic realms. They have a rich fossil record from the Phanerozoic eon lending insight into the early history of the group but, although cnidarians diverged from other animals in the Precambrian period, their record from the Ediacaran period (635-542 million years ago) is controversial. Here, we describe a new fossil cnidarian-Auroralumina attenboroughii gen. et sp. nov.-from the Ediacaran of Charnwood Forest (557-562 million years ago) that shows two bifurcating polyps enclosed in a rigid, polyhedral, organic skeleton with evidence of simple, densely packed tentacles. Auroralumina displays a suite of characters allying it to early medusozoans but shows others more typical of Anthozoa. Phylogenetic analyses recover Auroralumina as a stem-group medusozoan and, therefore, the oldest crown-group cnidarian. Auroralumina demonstrates both the establishment of the crown group of an animal phylum and the fixation of its body plan tens of millions of years before the Cambrian diversification of animal life.


Assuntos
Cnidários , Animais , Evolução Biológica , Florestas , Filogenia , Reino Unido
3.
Sci Data ; 6(1): 161, 2019 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-31467271

RESUMO

Sustained, quantitative observations of nearshore waves and sand levels are essential for testing beach evolution models, but comprehensive datasets are relatively rare. We document beach profiles and concurrent waves monitored at three southern California beaches during 2001-2016. The beaches include offshore reefs, lagoon mouths, hard substrates, and cobble and sandy (medium-grained) sediments. The data span two energetic El Niño winters and four beach nourishments. Quarterly surveys of 165 total cross-shore transects (all sites) at 100 m alongshore spacing were made from the backbeach to 8 m depth. Monthly surveys of the subaerial beach were obtained at alongshore-oriented transects. The resulting dataset consists of (1) raw sand elevation data, (2) gridded elevations, (3) interpolated elevation maps with error estimates, (4) beach widths, subaerial and total sand volumes, (5) locations of hard substrate and beach nourishments, (6) water levels from a NOAA tide gauge (7) wave conditions from a buoy-driven regional wave model, and (8) time periods and reaches with alongshore uniform bathymetry, suitable for testing 1-dimensional beach profile change models.

4.
R Soc Open Sci ; 5(3): 180154, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29658961

RESUMO

[This corrects the article DOI: 10.1098/rsos.170833.].

5.
Int J Cosmet Sci ; 40(2): 148-156, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29355981

RESUMO

OBJECTIVE: Examination of the skin barrier repair/wound healing process using a living skin equivalent (LSE) model and matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) to identify lipids directly involved as potential biomarkers. These biomarkers may be used to determine whether an in vivo wound is going to heal for example if infected. METHODS: An in vitro LSE model was wounded with a scalpel blade and assessed at day 4 post-wounding by histology and MALDI-MSI. Samples were sectioned at wound site and were either formalin-fixed paraffin-embedded (FFPE) for histology or snapped frozen (FF) for MSI analysis. RESULTS: The combination of using an in vitro wounded skin model with MSI allowed the identification of lipids involved in the skin barrier repair/wound healing process. The technique was able to highlight lipids directly in the wound site and distinguish differences in lipid distribution between the epidermis and wound site. CONCLUSION: This novel method of coupling an in vitro LSE with MSI allowed in-depth molecular analysis of the skin barrier repair/wound healing process. The technique allowed the identification of lipids directly involved in the skin barrier repair/wound healing process, indicating these biomarkers may be potentially be used within the clinic. These biomarkers will help to determine, which stage of the skin barrier repair/wound healing process the wound is in to provide the best treatment.


Assuntos
Pele/fisiopatologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Cicatrização , Biomarcadores/metabolismo , Análise Discriminante , Humanos , Técnicas In Vitro , Inclusão em Parafina , Análise de Componente Principal
6.
Br J Pharmacol ; 174(10): 1002-1014, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27590257

RESUMO

The peptide hormone relaxin regulates the essential maternal haemodynamic adaptations in early pregnancy through direct actions on the renal and systemic vasculature. These vascular actions of relaxin occur mainly through endothelium-derived NO-mediated vasodilator pathways and improvements in arterial compliance in small resistance-size arteries. This work catalysed a plethora of studies which revealed quite heterogeneous responses across the different regions of the vasculature, and also uncovered NO-independent mechanisms of relaxin action. In this review, we first describe the role of endogenous relaxin in maintaining normal vascular function, largely referring to work in pregnant and male relaxin-deficient animals. We then discuss the diversity of mechanisms mediating relaxin action in different vascular beds, including the involvement of prostanoids, VEGF, endothelium-derived hyperpolarisation and antioxidant activity in addition to the classic NO-mediated vasodilatory pathway. We conclude the review with current perspectives on the vascular remodelling capabilities of relaxin. LINKED ARTICLES: This article is part of a themed section on Recent Progress in the Understanding of Relaxin Family Peptides and their Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.10/issuetoc.


Assuntos
Endotélio Vascular/metabolismo , Óxido Nítrico/metabolismo , Relaxina/metabolismo , Animais , Humanos
7.
Br J Pharmacol ; 173(6): 1005-17, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26660642

RESUMO

BACKGROUND AND PURPOSE: In the RELAX-AHF trial, a 48 h i.v. serelaxin infusion reduced systemic vascular resistance in patients with acute heart failure. Consistent with preclinical studies, serelaxin augments endothelial vasodilator function in rat mesenteric arteries. Little is known about the contribution of endothelium-derived relaxing factors after a longer duration of continuous serelaxin treatment. Here we have assessed vascular reactivity and mechanistic pathways in mesenteric arteries and veins and the aorta after 48 or 72 h continuous i.v. infusion of serelaxin. EXPERIMENTAL APPROACH: Male rats were infused with either placebo or serelaxin (13.3 µg·kg(-1) ·h(-1) ) via the jugular vein using osmotic minipumps. Vascular function was assessed using wire myography. Changes in gene and protein expression and 6-keto PGF1α levels were determined by quantitative PCR, Western blot and ELISA respectively. KEY RESULTS: Continuous i.v. serelaxin infusion augmented endothelium-dependent relaxation in arteries (mesenteric and aorta) but not in mesenteric veins. In mesenteric arteries, 48 h i.v. serelaxin infusion increased basal NOS activity, associated with increased endothelial NOS (eNOS) expression. Interestingly, phosphorylated-eNOS(Ser1177) , eNOS and basal NOS activity were reduced in mesenteric arteries following 72 h serelaxin treatment. At 72 h, serelaxin treatment improved bradykinin-mediated relaxation through COX2-derived PGI2 production. CONCLUSIONS AND IMPLICATIONS: Continuous i.v. serelaxin infusion enhanced endothelial vasodilator function in arteries but not in veins. The underlying mediator at 48 h was NO but there was a transition to PGI2 by 72 h. Activation of the PGI2 -dependent pathway is key to the prolonged vascular response to serelaxin treatment.


Assuntos
Aorta Abdominal/efeitos dos fármacos , Epoprostenol/fisiologia , Artérias Mesentéricas/efeitos dos fármacos , Óxido Nítrico/fisiologia , Relaxina/farmacologia , Animais , Aorta Abdominal/fisiologia , Infusões Intravenosas , Masculino , Artérias Mesentéricas/fisiologia , Veias Mesentéricas/efeitos dos fármacos , Veias Mesentéricas/fisiologia , Ratos Wistar , Proteínas Recombinantes/sangue , Proteínas Recombinantes/farmacologia , Relaxina/sangue , Transdução de Sinais , Vasodilatação/efeitos dos fármacos
8.
Sci Total Environ ; 527-528: 530-9, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26003614

RESUMO

Peatlands are important sources of fluvial carbon. Previous research has shown that riverine dissolved organic carbon (DOC) concentrations are largely controlled by soil type. However, there has been little work to establish the controls of riverine DOC within blanket peatlands that have not undergone major disturbance from drainage or burning. A total of 119 peatland catchments were sampled for riverine DOC and water colour across three drainage basins during six repeated sampling campaigns. The topographic characteristics of each catchment were determined from digital elevation models. The dominant vegetation cover was mapped using 0.5m resolution colour infrared aerial images, with ground-truthed validation revealing 82% accuracy. Forward and backward stepwise regression modelling showed that mean slope was a strong (and negative) determinant of DOC and water colour in blanket peatland river waters. There was a weak role for plant functional type in determining DOC and water colour. At the basin scale, there were major differences between the models depending on the basin. The dominance of topographic predictors of DOC found in our study, combined with a weaker role of vegetation type, paves the way for developing improved planning tools for water companies operating in peatland catchments. Using topographic data and aerial imagery it will be possible to predict which tributaries will typically yield lower DOC concentrations and which are therefore more suitable and cost-effective as raw water intakes.

10.
Oncogene ; 32(7): 883-93, 2013 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-22469981

RESUMO

Although significant progress has been made in understanding the importance of Wnt signaling in the initiation of colorectal cancer, less is known about responses that accompany the reversal of oncogenic Wnt signaling. The aim of this study was to analyze in vivo and in vitro responses to an 'ideal' Wnt pathway inhibitor as a model for the therapeutic targeting of the pathway. A tetracycline-inducible transgenic mouse model expressing truncated ß-catenin (ΔN89ß-catenin) that exhibited a strong intestinal hyperplasia was analyzed during the removal of oncogenic ß-catenin expression both in 3D 'crypt culture' and in vivo. Oncogenic Wnt signaling was rapidly and completely reversed. The strongest inhibition of Wnt target gene expression occurred within 24 h of doxycycline removal at which time the target genes Ascl2, Axin2 and C-myc were downregulated to levels below that in the control intestine. In vitro, the small molecule Wnt inhibitor CCT036477 induced a response within 4 h of treatment. By 7 days following doxycycline withdrawal, gene expression, cell proliferation and tissue morphology were undistinguishable from control animals.In conclusion, these results demonstrate that the reversal of Wnt signaling by inhibitors should ideally be studied within hours of treatment. The reversible system described, involving medium throughput in vitro approaches and rapid in vivo responses, should allow the rapid advance of early stage compounds into efficacy models that are more usually considered later in the drug discovery pipeline.


Assuntos
Modelos Teóricos , Terapia de Alvo Molecular , Via de Sinalização Wnt/genética , beta Catenina/genética , Animais , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Técnicas de Cultura de Células , Células Cultivadas , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Genes Reporter/genética , Genes Reporter/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Terapia de Alvo Molecular/métodos , Estrutura Terciária de Proteína/genética , Proteínas Recombinantes de Fusão/genética , Via de Sinalização Wnt/fisiologia , beta Catenina/química
11.
Biochem Biophys Res Commun ; 413(1): 24-9, 2011 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-21867687

RESUMO

In mammals, the GCN2/ATF4 pathway has been described as the main pathway involved in the regulation of gene expression upon amino acid limitation. This regulation is notably conferred by the presence of a cis-element called Amino Acid Response Element (AARE) in the promoter of specific genes. In vivo, the notion of amino acid limitation is not limited to nutritional context, indeed several pathological situations are associated with alteration of endogenous amino acid availability. This is notably true in the context of tumour in which the alteration of the microenvironment can lead to a perturbation in nutrient availability. P8 is a small weakly folded multifunctional protein that is overexpressed in several kinds of cancers and whose expression is induced by different stresses. In this study we have demonstrated that amino acid starvation was also able to induce p8 expression. Moreover, we brought the evidence, in vitro and in vivo, that the GCN2/ATF4 pathway is involved in this regulation through the presence of an AARE in p8 promoter.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Aminoácidos/deficiência , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica , Proteínas de Neoplasias/genética , Proteínas Serina-Treonina Quinases/metabolismo , Elementos Reguladores de Transcrição , Animais , Leucina/deficiência , Camundongos , Células NIH 3T3
12.
Neurogastroenterol Motil ; 22(11): 1209-16, e317, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20626789

RESUMO

BACKGROUND: Vasoactive intestinal peptide (VIP) submucosal neurons, the main regulators of gut secretion, display inhibitory postsynaptic potentials mediated by somatostatin (SOM) acting on SST(1) and SST(2) receptors (SSTR(1), SSTR(2)) in the guinea-pig small intestine. We investigated the implications of this for neurally-evoked mucosal secretion. METHODS: Mucosal-submucosal preparations from guinea-pig jejunum were mounted in Ussing chambers to measure Cl(-) secretion, measured by short circuit current (I(sc)). All drugs were added serosally. Veratridine (1 µmol L(-1)) was used to stimulate neurons and provide a robust secretory response for pharmacological testing.5-hydroxytrptamine (5-HT, 300 nmol L(-1)) was used to specifically activate non-cholinergic secretomotor neurons, while 1,1-dimethyl-4-phenylpiperazinium (DMPP, 10 µmol L(-1)) was used to stimulate all secretomotor neurons. KEY RESULTS: Somatostatin (50 nmol L(-1)) induced a tetrodotoxin (TTX, 1 µmol L(-1))-sensitive decrease in secretion. Somatostatin also reduced the veratridine-induced increase in I(sc). The effects of SOM were significantly reduced by blocking SSTR(1) and SSTR(2) individually or together. Blocking SSTR(1) abolished the inhibition produced by SOM. Quantitative PCR demonstrated that SSTR(1) and SSTR(2) were much more highly expressed in the submucosa than the mucosa. Submucosal SSTR(1) expression was several fold higher than SSTR(2). Responses to DMPP (biphasic) and 5-HT (monophasic) were TTX-sensitive. Somatostatin significantly reduced the 5-HT-induced increase in I(sc), and the second, more sustained phase evoked by DMPP. CONCLUSIONS & INFERENCES: These data suggest that SOM exerts its antisecretory effects by suppressing firing of VIP secretomotor neurons, rather than via a direct action on mucosal enterocytes.


Assuntos
Jejuno/inervação , Jejuno/metabolismo , Receptores de Somatostatina/efeitos dos fármacos , Animais , Cloretos/metabolismo , Cultura em Câmaras de Difusão , Iodeto de Dimetilfenilpiperazina/farmacologia , Fenômenos Eletrofisiológicos , Feminino , Expressão Gênica/genética , Expressão Gênica/fisiologia , Cobaias , Jejuno/efeitos dos fármacos , Masculino , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Agonistas Nicotínicos/farmacologia , RNA/biossíntese , RNA/genética , Receptores de Somatostatina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serotonina/farmacologia , Somatostatina/farmacologia , Tetrodotoxina/farmacologia , Veratridina/farmacologia
13.
Med Sci Law ; 49(3): 179-84, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19787989

RESUMO

In the U.K., cases of sudden unexpected death in infancy are under the jurisdiction of the Coroner and consent for a post-mortem is not required. Prior to the Human Tissue Act 2006 (HTA) there was also no requirement to request retention of tissue (blocks and slides). The HTA stipulates that parental/ guardian consent is mandatory to retain or dispose of all tissues after the Coroners' purposes have been fulfilled. In 2007, in order to avoid confusion with the consent needed for hospital post-mortems, a new form was introduced by Sheffield Children's Hospital NHS Foundation Trust (SCH) called Record of parents'/guardians'wishes regarding samples taken at a Coroner's post mortem. This version specifically asks if blocks and slides may be retained as part of the medical record, or are to be disposed of, and for parental agreement (or not) for the frozen tissue, blocks and slides to be used for education, audit, quality control and medical research. One hundred and nineteen Coroners' postmortems covering the years 2006-2007 were reviewed. All parents/guardians (P/G) were contacted and the outcomes of P/G wishes recorded by SCH staff, Coroners' Officers (CO) and Police Family Liaison Officers (PFLO) were analysed and compared (44% from CO were outstanding at the time of audit). Any delay in recording P/G wishes by these three groups was also compared. In 2006, parental agreement to the use of blocks and slides for education, audit, quality control and medical research was 94%, 77% and 75% for SCH, CO and PFLO, respectively. In 2007 it was 84%, 37% and 100% for the same groups. Permission for the retention of frozen tissue given to SCH, CO and PFLO was 90%, 62% and 100% in 2006 and 90%, 44% and 100% in 2007, respectively. Cases where parents did not wish for the retention or use of tissue (including blocks and slides) were 3%, 15% and 0% in 2006 for SCH, CO and PFLO respectively, and 0% for all groups in 2007. Training of staff in all aspects of post-mortem and bereavement care is essential for ascertaining parental wishes. Families should be provided with the knowledge that allows them to make informed choices. The analysis of the results of the audit supports this view.


Assuntos
Autopsia/legislação & jurisprudência , Tutores Legais , Pais , Morte Súbita do Lactente , Obtenção de Tecidos e Órgãos/legislação & jurisprudência , Atitude Frente a Saúde , Humanos , Lactente , Consentimento Livre e Esclarecido/legislação & jurisprudência , Auditoria Médica , Estudos Retrospectivos , Reino Unido
14.
Clin Exp Allergy ; 39(5): 760-70, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19226276

RESUMO

BACKGROUND: As a complex molecule requiring post-translational processing, it has been difficult to produce the Der p 1 major allergen from the Dermatophagoides pteronyssinus house dust mite in a recombinant form. OBJECTIVE: Here, we tested whether transgenic tobacco plants are suitable to express Der p 1, either as a wild-type molecule or as variants lacking N-glycosylation sites (Gly(-)) and/or cysteine protease activity (Enz(-)). Methods Using Agrobacterium tumefaciens-based transformation, pro Der p 1 molecules bearing mutations within either the N-glycosylation sites (N34Q, N150Q) and/or the cysteine protease-active site (C132V) were expressed in tobacco plants. After purification by ion exchange chromatography, allergens were characterized using immunoblotting, circular dichroism (CD), as well as basophil and T lymphocyte stimulation assays. RESULTS: Four forms of recombinant Der p 1 (i.e. wild-type Gly(+)/Enz(+), as well as Gly(-)/Enz(+), Gly(+)/Enz(-) or Gly(-)/Enz(-) variants) were successfully expressed in tobacco leaves as pro Der p 1 molecules. Spontaneous cleavage of the pro-peptide was observed in tobacco leaf extracts for all forms of recombinant Der p 1 (r Der p 1). CD confirmed that all r Der p 1 molecules, with the exception of the Gly(-)/Enz(-) variant, exhibited secondary structures comparable to the natural protein. A cysteine protease activity was associated only with the Gly(+)/Enz(+) form. All these molecules exhibit a profile similar to natural Der p 1 with respect to IgE immunoreactivity, basophil activation and T cell recognition. CONCLUSION: A tobacco plant expression system allows the production of various forms of mature Der p 1, which could be used for diagnostic or immunotherapeutic purposes.


Assuntos
Antígenos de Dermatophagoides/biossíntese , Clonagem Molecular , Nicotiana/genética , Antígenos de Dermatophagoides/genética , Antígenos de Dermatophagoides/imunologia , Proteínas de Artrópodes , Basófilos/imunologia , Basófilos/metabolismo , Linhagem Celular , Cisteína Endopeptidases , Humanos , Diester Fosfórico Hidrolases/imunologia , Diester Fosfórico Hidrolases/metabolismo , Folhas de Planta/genética , Plantas Geneticamente Modificadas , Pirofosfatases/imunologia , Pirofosfatases/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
15.
Proc Natl Acad Sci U S A ; 104(47): 18555-60, 2007 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-18003934

RESUMO

Biodiversity loss from deforestation may be partly offset by the expansion of secondary forests and plantation forestry in the tropics. However, our current knowledge of the value of these habitats for biodiversity conservation is limited to very few taxa, and many studies are severely confounded by methodological shortcomings. We examined the conservation value of tropical primary, secondary, and plantation forests for 15 taxonomic groups using a robust and replicated sample design that minimized edge effects. Different taxa varied markedly in their response to patterns of land use in terms of species richness and the percentage of species restricted to primary forest (varying from 5% to 57%), yet almost all between-forest comparisons showed marked differences in community structure and composition. Cross-taxon congruence in response patterns was very weak when evaluated using abundance or species richness data, but much stronger when using metrics based upon community similarity. Our results show that, whereas the biodiversity indicator group concept may hold some validity for several taxa that are frequently sampled (such as birds and fruit-feeding butterflies), it fails for those exhibiting highly idiosyncratic responses to tropical land-use change (including highly vagile species groups such as bats and orchid bees), highlighting the problems associated with quantifying the biodiversity value of anthropogenic habitats. Finally, although we show that areas of native regeneration and exotic tree plantations can provide complementary conservation services, we also provide clear empirical evidence demonstrating the irreplaceable value of primary forests.


Assuntos
Biodiversidade , Agricultura Florestal , Clima Tropical
16.
J Neuroendocrinol ; 16(4): 398-402, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15089981

RESUMO

The oxytocin receptor is an important contractile-associated protein, up-regulated at term in the myometrium in many mammalian species. We conducted studies in a novel animal model to challenge the general view that gonadal steroids are a major regulatory factor of uterine oxytocin receptors. Female marsupials have separate uteri and, in monovular species such as the tammar wallaby, the conceptus is present in one uterus whereas the contralateral uterus is empty. A marked increase in myometrial oxytocin receptors occurs only in the gravid uterus. Fetectomy experiments demonstrated that local embryo-derived factors stimulate this gravid uterus-specific increase in oxytocin receptors, and that uterine distension is probably not a key component in this regulatory pathway. Unilateral ovariectomy has no significant effect on uterine oxytocin receptors, emphasizing the impact of the conceptus on oxytocin receptor regulation and the minimal influence of gonadal steroids on parturition in this species. Our data highlight that regulation of uterine oxytocin receptor expression is multifactorial, and does not necessarily rely on gonadal steroids.


Assuntos
Estrogênios/metabolismo , Macropodidae/metabolismo , Progesterona/metabolismo , Receptores de Ocitocina/metabolismo , Útero/metabolismo , Animais , Feminino
17.
Colorectal Dis ; 6(2): 92-6, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15008905

RESUMO

OBJECTIVE: To assess the anal function of women who have suffered a third degree perineal tear during parturition. PATIENTS: Fifty-three consecutive women who sustained a third degree tear, between January 1998 and March 2000, at the Princess Anne Maternity Unit, Royal Bolton Hospital were assessed. METHODS: Women were assessed at 3 months post partum using the Cleveland Clinic Incontinence Score, digital assessment of anal sphincter and endo-anal ultrasound scan. RESULTS: At 3 months post partum 75% of the participants had no symptoms of anal incontinence, 18% had mild symptoms and 7% had more severe symptoms. Anal endosonography demonstrated normal anal sphincters in 66% of participants, an abnormality in the external sphincter in 29% and a defect in both sphincters in 2%. There was poor correlation between symptoms and scan defects. CONCLUSION: The incidence of anal incontinence following repair of a third degree tear was not high and it is unlikely that we are missing a hidden pool of symptomatic women. No major change in management policy is required. The routine assessment of anal function in women who had sustained a third degree tear was appreciated by the women and enabled us to identify the small portion of women with significant symptoms.


Assuntos
Canal Anal/lesões , Doenças do Ânus/etiologia , Parto Obstétrico/efeitos adversos , Canal Anal/diagnóstico por imagem , Canal Anal/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Endossonografia/métodos , Feminino , Humanos , Recuperação de Função Fisiológica , Resultado do Tratamento
18.
Dis Aquat Organ ; 54(3): 175-86, 2003 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-12803381

RESUMO

Between 1995 and 1998, marine fish from around the coast of the UK were collected and samples analysed for viral haemorrhagic septicaemia virus (VHSV) using cell culture isolation methods. In 1997 and 1998 the samples were also analysed for VHSV by reverse transcription PCR (RT-PCR). A total of 1867 fish of 11 species were tested, but VHSV was isolated on only 1 occasion, from herring Clupea harengus, in 1996. However, despite VHSV not being isolated in 1997 and 1998, in both years samples of herring from the west and south coasts of England produced positive signals in the RT-PCR, and in 1997 cod from the east coast of England also produced positive signals in the RT-PCR. These results are believed to be true indications of the presence of VHSV nucleic acid in the fish. In 1997, birnaviruses from Serogroup B1 were isolated from herring (a previously unrecorded host for the virus) and cod Gadus morhua, and a birnavirus from Serogroup A2 was also isolated from cod. In 1998, an aquareovirus was isolated from haddock Melanogrammus aeglefinus, a previously unrecorded host for the virus.


Assuntos
Septicemia Hemorrágica Viral/epidemiologia , Novirhabdovirus/isolamento & purificação , Animais , Sequência de Bases , Birnaviridae/isolamento & purificação , Infecções por Birnaviridae/epidemiologia , Infecções por Birnaviridae/veterinária , Linhagem Celular , Ensaio de Imunoadsorção Enzimática/veterinária , Peixes , Dados de Sequência Molecular , Novirhabdovirus/genética , RNA Viral/química , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Água do Mar , Alinhamento de Sequência/veterinária , Homologia de Sequência do Ácido Nucleico , Reino Unido/epidemiologia , Microbiologia da Água
19.
Hum Mol Genet ; 10(25): 2899-905, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11741833

RESUMO

Critical functions of hamartin and tuberin, encoded by the TSC1 and TSC2 genes, are likely to be closely linked. The proteins interact directly with one another and mutations affecting either gene result in the tuberous sclerosis phenotype. However, the regions of hamartin and tuberin that interact have not been well defined, and the relationship between their interaction and the pathogenesis of tuberous sclerosis has not been explored. To address these issues a series of hamartin and tuberin constructs were used to assay for interaction in the yeast two-hybrid system. Hamartin (amino acids 302-430) and tuberin (amino acids 1-418) interacted strongly with one another. A region of tuberin encoding a putative coiled-coil (amino acids 346-371) was necessary but not sufficient to mediate the interaction with hamartin, as more N-terminal residues were also required. A region of hamartin (amino acids 719-998) predicted to encode coiled-coils was capable of oligermerization but was not important for the interaction with tuberin. Subtle, non-truncating mutations identified in patients with tuberous sclerosis and located within the putative binding regions of hamartin (N198_F199delinsI;593-595delACT) or tuberin (G294E and I365del), abolished or dramatically reduced interaction of the proteins as assessed by yeast two-hybrid assays and by co-immunoprecipitation of the full-length proteins from Cos7 cells. In contrast, three non-pathogenic missense polymorphisms of tuberin (R261W, M286V, R367Q) in the same region as the disease-causing TSC2 mutations did not. These results indicate a requirement for interaction in critical growth suppressing functions of hamartin and tuberin.


Assuntos
Mutação/genética , Proteínas/genética , Proteínas Repressoras/genética , Esclerose Tuberosa/genética , Animais , Sítios de Ligação , Células COS/citologia , Eletroforese em Gel de Poliacrilamida , Deleção de Genes , Genes Supressores de Tumor/fisiologia , Humanos , Immunoblotting , Técnicas Imunoenzimáticas , Ativação Linfocitária , Chaperonas Moleculares , Mutagênese Sítio-Dirigida , Fosforilação , Plasmídeos , Ligação Proteica , Proteínas/metabolismo , Proteínas Repressoras/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Esclerose Tuberosa/metabolismo , Proteína 1 do Complexo Esclerose Tuberosa , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor , Técnicas do Sistema de Duplo-Híbrido
20.
Br J Cancer ; 85(8): 1226-30, 2001 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-11710839

RESUMO

The genetic events involved in the aetiology of non-clear-cell renal cell carcinoma (RCC) and a proportion of clear cell RCC remain to be defined. Germline mutations of the TSC1 and TSC2 genes cause tuberous sclerosis (TSC), a multi-system hamartoma syndrome that is also associated with RCC. We assessed 17 sporadic clear cell RCCs with a previously identified VHL mutation, 15 clear-cell RCCs without an identified VHL mutation and 15 non-clear-cell RCCs for loss of heterozygosity (LOH) at chromosomes 9q34 and 16p13.3, the chromosomal locations of TSC1 and TSC2. LOH was detected in 4/9, 1/11 and 3/13 cases informative at both loci. SSCP analysis of the whole coding region of the retained allele did not reveal any cases with a detectable intragenic second somatic mutation. Furthermore, RT-PCR analysis of TSC1 and TSC2 on total RNA from 8 clear-cell RCC cell lines confirmed expression of both TSC genes. These data indicate that biallelic inactivation of TSC1 or TSC2 is not frequent in sporadic RCC and suggests that the molecular mechanisms of renal carcinogenesis in TSC are likely to be distinct.


Assuntos
Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Proteínas/genética , Proteínas Repressoras/genética , Alelos , Humanos , Perda de Heterozigosidade , Polimorfismo Conformacional de Fita Simples , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína 1 do Complexo Esclerose Tuberosa , Proteína 2 do Complexo Esclerose Tuberosa , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor
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