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1.
Prenat Diagn ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38708840

RESUMO

OBJECTIVES: To determine the incremental yield of prenatal exome sequencing (PES) over standard testing in fetuses with an isolated congenital heart abnormality (CHA), CHA associated with extra-cardiac malformations (ECMs) and CHA dependent upon anatomical subclassification. METHODS: A systematic review of the literature was performed using MEDLINE, EMBASE, Web of Science and grey literature January 2010-February 2023. Studies were selected if they included greater than 20 cases of prenatally diagnosed CHA when standard testing (QF-PCR/chromosome microarray/karyotype) was negative. Pooled incremental yield was determined. PROSPERO CRD 42022364747. RESULTS: Overall, 21 studies, incorporating 1957 cases were included. The incremental yield of PES (causative pathogenic and likely pathogenic variants) over standard testing was 17.4% (95% CI, 13.5%-21.6%), 9.3% (95% CI, 6.6%-12.3%) and 35.9% (95% CI, 21.0%-52.3%) for all CHAs, isolated CHAs and CHAs associated with ECMs. The subgroup with the greatest yield was complex lesions/heterotaxy; 35.2% (95% CI 9.7%-65.3%). The most common syndrome was Kabuki syndrome (31/256, 12.1%) and most pathogenic variants occurred de novo and in autosomal dominant (monoallelic) disease causing genes (114/224, 50.9%). CONCLUSION: The likelihood of a monogenic aetiology in fetuses with multi-system CHAs is high. Clinicians must consider the clinical utility of offering PES in selected isolated cardiac lesions.

2.
J Child Health Care ; : 13674935231222943, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38174717

RESUMO

The Congenital Heart Disease Standards for England indicate that parents and children should have access to a 24-h telephone advice service, however, little is known about existing services. This paper presents phase two of a mixed-methods service evaluation, which aimed to evaluate staff experiences of telephone communication with these parents. All nursing and support staff in a single specialist children's cardiac surgical centre were invited to participate in an online survey during July-November 2019. Data were descriptively and thematically analysed. Participants (N = 39) were predominantly nurses (n = 32, 82%) with 64.1% (n = 25) working in the speciality >10 years. Positive experiences included: signposting and preventing further deterioration; supporting families to get expert advice quickly; providing reassurance. Challenging experiences included: offering advice without being able to see the child, dealing with telephone calls alongside busy workload; and parents running out of medications and telephoning out of hours. In conclusion, taking telephone calls were perceived to be time consuming and are potentially high risk. A standardised approach to assessment, intervention and documentation was deemed necessary. Implementation of an updated parental early warning tool was recommended, along with staff and parental education.

3.
Pediatr Surg Int ; 39(1): 12, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36441283

RESUMO

INTRODUCTION: Exomphalos is an anterior abdominal wall defect resulting in herniation of contents into the umbilical cord. Severe associated chromosomal anomalies and congenital heart disease (CHD) are known to influence mortality, but it is not clear which cardiac anomalies have the greatest impact on survival. METHODS: We performed a retrospective review of the treatment and outcome of patients with exomphalos over a 30-year period (1990-2020), with a focus on those with the combination of exomphalos major and major CHD (EMCHD). RESULTS: There were 123 patients with exomphalos identified, 59 (48%) had exomphalos major (ExoMaj) (defect > 5 cm or containing liver), and 64 (52%) exomphalos minor (ExoMin). In the ExoMaj group; 17% had major CHD (10/59), M:F 28:31, 29% premature (< 37 weeks, 17/59) and 14% had low birth-weight (< 2.5 kg, 8/59). In the ExoMin group; 9% had major CHD (6/64), M:F 42:22, 18% premature and 10% had low birth-weight. The 5-year survival was 20% in the EMCHD group versus 90% in the ExoMaj with minor or no CHD [p < 0.0001]. Deaths in the EMCHD had mainly right heart anomalies and all of them required mechanical ventilation (MV) for pulmonary hypoplasia prior to cardiac intervention. In contrast, survivors did not require mechanical ventilation prior to cardiac intervention. CONCLUSION: EMCHD is associated with high mortality. The most significant finding was high mortality in those with right heart anomalies in combination with pulmonary hypoplasia, especially if pre-intervention mechanical ventilation is required.


Assuntos
Cardiopatias Congênitas , Hérnia Umbilical , Nascimento Prematuro , Humanos , Feminino , Hérnia Umbilical/terapia , Aberrações Cromossômicas , Respiração Artificial
4.
Artigo em Inglês | MEDLINE | ID: mdl-30249685

RESUMO

Carbapenem-resistant Enterobacteriaceae (CRE) represent a health threat, but effective control interventions remain unclear. Hospital wastewater sites are increasingly being highlighted as important potential reservoirs. We investigated a large Klebsiella pneumoniae carbapenemase (KPC)-producing Escherichia coli outbreak and wider CRE incidence trends in the Central Manchester University Hospital NHS Foundation Trust (CMFT) (United Kingdom) over 8 years, to determine the impact of infection prevention and control measures. Bacteriology and patient administration data (2009 to 2017) were linked, and a subset of CMFT or regional hospital KPC-producing E. coli isolates (n = 268) were sequenced. Control interventions followed international guidelines and included cohorting, rectal screening (n = 184,539 screens), environmental sampling, enhanced cleaning, and ward closure and plumbing replacement. Segmented regression of time trends for CRE detections was used to evaluate the impact of interventions on CRE incidence. Genomic analysis (n = 268 isolates) identified the spread of a KPC-producing E. coli outbreak clone (strain A, sequence type 216 [ST216]; n = 125) among patients and in the environment, particularly on 2 cardiac wards (wards 3 and 4), despite control measures. ST216 strain A had caused an antecedent outbreak and shared its KPC plasmids with other E. coli lineages and Enterobacteriaceae species. CRE acquisition incidence declined after closure of wards 3 and 4 and plumbing replacement, suggesting an environmental contribution. However, ward 3/ward 4 wastewater sites were rapidly recolonized with CRE and patient CRE acquisitions recurred, albeit at lower rates. Patient relocation and plumbing replacement were associated with control of a clonal KPC-producing E. coli outbreak; however, environmental contamination with CRE and patient CRE acquisitions recurred rapidly following this intervention. The large numbers of cases and the persistence of blaKPC in E. coli, including pathogenic lineages, are of concern.


Assuntos
Infecção Hospitalar/epidemiologia , Surtos de Doenças , Infecções por Escherichia coli/epidemiologia , Escherichia coli/genética , Klebsiella pneumoniae/genética , beta-Lactamases/genética , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Infecção Hospitalar/transmissão , DNA Bacteriano/genética , Reservatórios de Doenças/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Escherichia coli/patogenicidade , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/transmissão , Expressão Gênica , Transferência Genética Horizontal , Genótipo , Hospitais Universitários , Humanos , Controle de Infecções/métodos , Klebsiella pneumoniae/patogenicidade , Resíduos de Serviços de Saúde , Filogenia , Prevalência , Reino Unido/epidemiologia , Águas Residuárias/microbiologia
6.
Gen Comp Endocrinol ; 192: 191-203, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23722201

RESUMO

Prolactin (PRL) cells of the Mozambique tilapia, Oreochromis mossambicus, are osmoreceptors by virtue of their intrinsic osmosensitivity coupled with their ability to directly regulate hydromineral homeostasis through the actions of PRL. Layered upon this fundamental osmotic reflex is an array of endocrine control of PRL synthesis and secretion. Consistent with its role in fresh water (FW) osmoregulation, PRL release in tilapia increases as extracellular osmolality decreases. The hyposmotically-induced release of PRL can be enhanced or attenuated by a variety of hormones. Prolactin release has been shown to be stimulated by gonadotropin-releasing hormone (GnRH), 17-ß-estradiol (E2), testosterone (T), thyrotropin-releasing hormone (TRH), atrial natriuretic peptide (ANP), brain-natriuretic peptide (BNP), C-type natriuretic peptide (CNP), ventricular natriuretic peptide (VNP), PRL-releasing peptide (PrRP), angiotensin II (ANG II), leptin, insulin-like growth factors (IGFs), ghrelin, and inhibited by somatostatin (SS), urotensin-II (U-II), dopamine, cortisol, ouabain and vasoactive intestinal peptide (VIP). This review is aimed at providing an overview of the hypothalamic and extra-hypothalamic hormones that regulate PRL release in euryhaline Mozambique tilapia, particularly in the context on how they may modulate osmoreception, and mediate the multifunctional actions of PRL. Also considered are the signal transduction pathways through which these secretagogues regulate PRL cell function.


Assuntos
Prolactina/genética , Angiotensina II/metabolismo , Animais , Hormônio Liberador de Gonadotropina/metabolismo , Peptídeo Natriurético Tipo C/metabolismo , Concentração Osmolar , Hormônio Liberador de Prolactina/metabolismo , Somatomedinas/metabolismo , Somatostatina/metabolismo , Tilápia
7.
Ultrasound Obstet Gynecol ; 41(5): 589-91, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23288807

RESUMO

The ductus venosus (DV) connects the portal venous system to the inferior vena cava. Rarely, the umbilical venous drainage is anomalous, either connecting to the portal sinus within the liver or having an extrahepatic connection, bypassing the liver and draining to one of a variety of sites, including to the heart directly. Prenatally, there is a recognized association of anomalous umbilical venous drainage with aneuploidy and other structural malformations. The fetus may also develop right heart failure because of unregulated volume loading. We report the postnatal development of diaphragmatic hernia in three fetuses with absent DV and umbilical venous drainage to the right atrium directly in two cases and to the coronary sinus in the third. In all fetuses, the abnormality was well-tolerated in pregnancy, with only a modest degree of right heart dilatation. All three neonates underwent repair of the diaphragmatic hernia and made a good recovery.


Assuntos
Feto/anormalidades , Hérnia Diafragmática/etiologia , Veias Umbilicais/anormalidades , Humanos , Lactente
9.
Ultrasound Obstet Gynecol ; 40(1): 47-54, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22461316

RESUMO

OBJECTIVES: Isolated fetal coarctation of the aorta (CoA) has high false-positive diagnostic rates by cardiologists in tertiary centers. Isthmal diameter Z-scores (I), ratio of isthmus to duct diameters (I:D), and visualization of CoA shelf (Shelf) and isthmal flow disturbance (Flow) distinguish hypoplastic from normal aortic arches in retrospective studies, but their ability to predict a need for perinatal surgery is unknown. The aim of this study was to determine whether these four sonographic features could differentiate prenatally cases which would require neonatal surgery in a prospective cohort diagnosed with CoA by a cardiologist. METHODS: From 83 referrals with cardiac disproportion (January 2006 to August 2010), we identified 37 consecutive fetuses diagnosed with CoA. Measurements of I and I:D were made and the presence of Shelf or Flow recorded. Sensitivity, specificity and areas under receiver-operating characteristics curves, using previously reported limits of I < - 2 and I:D < 0.74, as well as Shelf and Flow were compared at first and final scan. Associations between surgery and predictors were compared using multivariable logistic regression and changes in measurements using ANCOVA. RESULTS: Among the 37 fetuses, 30 (81.1%) required surgery and two with an initial diagnosis of CoA were revised to normal following isthmal growth, giving an 86% diagnostic accuracy at term. The median age at first scan was 22.4 (range. 16.6-7.0) weeks and the median number of scans per fetus was three (range, one to five). I < - 2 at final scan was the most powerful predictor (odds ratio, 3.6 (95% CI, 0.47-27.3)). Shelf was identified in 66% and Flow in 50% of fetuses with CoA. CONCLUSION: Incorporation of these four sonographic parameters in the assessment of fetuses with suspected CoA at a tertiary center resulted in better diagnostic precision regarding which cases would require neonatal surgery than has been reported previously.


Assuntos
Coartação Aórtica/diagnóstico por imagem , Ecocardiografia , Ultrassonografia Pré-Natal , Adulto , Coartação Aórtica/embriologia , Coartação Aórtica/fisiopatologia , Reações Falso-Negativas , Feminino , Idade Gestacional , Humanos , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos , Sensibilidade e Especificidade
10.
Ultrasound Obstet Gynecol ; 40(3): 310-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22262371

RESUMO

OBJECTIVES: To investigate whether prenatal screening is effective in the detection of total anomalous pulmonary venous connection (TAPVC) and to identify common prenatal features. METHODS: This was a retrospective collaborative study involving 19 pediatric cardiac centers in the UK, Ireland and Sweden. Cases with TAPVC born between January 1, 1998 and December 31, 2004, and prenatally diagnosed cases whose estimated dates of delivery were within this time frame, were identified. Cases with functionally univentricular circulation or atrial isomerism were excluded. All available data and stored images were reviewed. RESULTS: Four-hundred and twenty-four cases with TAPVC were identified prenatally or postnatally, of whom eight (1.9%) had a prenatal diagnosis of TAPVC. Median gestational age at fetal diagnosis was 26 + 6 (range, 22 + 4 to 32 + 0) weeks. Six further fetuses with TAPVC had an abnormality diagnosed on prenatal ultrasound, but not the TAPVC. This included other congenital heart defects (four cases) and isolated pleural effusion (two cases). Seventeen (4.0%) of the 422 liveborn infants had a first-degree relative with congenital heart disease; and six of 17 had a sibling with TAPVC. Two died in utero. Of the liveborn infants diagnosed prenatally with TAPVC, none required urgent intervention for pulmonary venous obstruction and all were alive and well at a median of 2.3 (range, 1.0-7.0) years after surgical repair. CONCLUSION: Prenatal diagnosis of TAPVC is infrequent using current screening methods. Where there is a family history of TAPVC, specialized fetal echocardiography at 20 and 28 weeks' gestation may be indicated.


Assuntos
Ecocardiografia/métodos , Cardiopatias Congênitas/diagnóstico por imagem , Diagnóstico Pré-Natal/métodos , Síndrome de Cimitarra/diagnóstico por imagem , Feminino , Humanos , Irlanda , Gravidez , Estudos Retrospectivos , Síndrome de Cimitarra/epidemiologia , Suécia , Reino Unido
11.
Gen Comp Endocrinol ; 176(3): 354-60, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22036842

RESUMO

Osmoregulation is essential to life in vertebrates and osmoreception is a fundamental element in osmoregulation. Progress in characterizing the mechanisms that mediate osmoreception has been made possible by using a uniquely accessible cell model, the prolactin (PRL) cell of the euryhaline tilapia, Oreochromis mossambicus. In addition to a brief historical overview, we offer a summary of our recent progress on signal transduction and osmosensitivity in the tilapia PRL cell model. Prolactin is a central regulator of hydromineral balance in teleosts in freshwater (FW). Consistent with its essential role in FW osmoregulation, PRL release in tilapia is inversely related to extracellular osmolality, both in vivo and in vitro. Osmotically-driven changes in PRL cell volume control PRL release. A decrease in extracellular osmolality increases cell volume, leading to a rapid influx of Ca(2+) through stretch-activated channels followed by a sharp rise in PRL release. Our recent studies also suggest that cAMP is involved in the osmotic signal transduction, and that acclimation salinity can modulate PRL cell osmosensitivity. Prolactin cells from FW tilapia show a larger rise in PRL release after a reduction in medium osmolality than those from SW fish. Paradoxically, hyposmotically-induced increase in PRL mRNA was observed only in cells from SW fish. Our studies have revealed differences in the abundance of the water channel, aquaporin 3 (AQP3), and the stretch activated Ca(2+) channel, transient receptor potential vanilloid 4 (TRPV4) in PRL cells of FW and SW fish that may explain their differing osmosensitivity and osmoreceptive output in differing acclimation salinities.


Assuntos
Hipófise/fisiologia , Prolactina/fisiologia , Transdução de Sinais/fisiologia , Tilápia/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Animais , Aquaporina 3/fisiologia , Água Doce , Salinidade , Canais de Cátion TRPV/fisiologia
12.
J Endocrinol ; 209(2): 237-44, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21330335

RESUMO

We identified and investigated the changes in expression of two gill Na(+), K(+)-ATPase α-subunit isoforms (α-1a and α-1b) in relationship with salinity acclimation in a cichlid fish, Mozambique tilapia. Transfer of freshwater (FW)-acclimated fish to seawater (SW) resulted in a marked reduction in α-1a expression within 24 h and a significant increase in α-1b expression with maximum levels attained 7 days after the transfer. In contrast, transfer of SW-acclimated fish to FW induced a marked increase in α-1a expression within 2 days, while α-1b expression decreased significantly after 14 days. Hypophysectomy resulted in a virtual shutdown of α-1a mRNA expression in both FW- and SW-acclimated fish, whereas no significant effect was observed in α-1b expression. Replacement therapy by ovine prolactin (oPrl) fully restored α-1a expression in FW-acclimated fish, while cortisol had a modest, but significant, stimulatory effect on α-1a expression. In hypophysectomized fish in SW, replacement therapy with oPrl alone or in combination with cortisol resulted in a marked increase in α-1a mRNA to levels far exceeding those observed in sham-operated fish. Expression of α-1b mRNA was unaffected by hormone treatment either in FW-acclimated fish or in SW-acclimated fish. The mRNA expression of fxyd-11, a regulatory Na(+), K(+)-ATPase subunit, was transiently enhanced during both FW and SW acclimation. In hypophysectomized fish in FW, oPrl and cortisol stimulated fxyd-11 expression in a synergistic manner. The clear Prl dependence of gill α-1a expression may partially explain the importance of this hormone to hyperosmoregulation in this species.


Assuntos
Brânquias/enzimologia , Prolactina/metabolismo , Salinidade , ATPase Trocadora de Sódio-Potássio/metabolismo , Tilápia/metabolismo , Aclimatação , Animais , Proteínas de Peixes/metabolismo , Hipofisectomia , Isoenzimas/metabolismo , Masculino
15.
Heart ; 95(23): 1944-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19737738

RESUMO

OBJECTIVE: To describe clinical features, morphology, management and outcome of pulmonary vein stenosis (PVS) in childhood. DESIGN AND SETTING: Retrospective international collaborative study involving 19 paediatric cardiology centres in the UK, Ireland and Sweden. PATIENTS: Cases of PVS presenting between 1 January 1995 and 31 December 2004 were identified. Cases where pulmonary veins connected to a morphological left atrium were included. Functionally univentricular hearts and total anomalous pulmonary venous connection were excluded. All available data and imaging were reviewed. RESULTS: 58 cases were identified. In 22 cases (38%) there was premature delivery. 46 (79%) had associated cardiac lesions; 16 (28%) had undergone previous cardiac surgery before PVS diagnosis. 16 children (28%) had a syndrome or significant extracardiac abnormality. 36 presented with unilateral disease of which 86% was on the left. Where there was adequate sequential imaging, disease progression was shown with discrete stenosis leading to diffusely small pulmonary veins. Collateral vessels often developed. 13 patients had no intervention. Initial intervention was by catheter in 17 and surgery in 28. Overall 3-year survival was 49% (95% CI 35% to 63%) with patients undergoing initial surgical intervention having greater freedom from death or re-intervention (hazard ratio 0.44, 95% CI 0.2 to 0.99, p = 0.023). CONCLUSIONS: PVS is a complex disease of uncertain cause and frequently associated with prematurity. Early intervention may be indicated to deter irreversible secondary changes.


Assuntos
Doenças do Prematuro/patologia , Doenças do Prematuro/terapia , Pneumopatia Veno-Oclusiva/patologia , Pneumopatia Veno-Oclusiva/terapia , Adolescente , Criança , Pré-Escolar , Constrição Patológica/mortalidade , Constrição Patológica/patologia , Constrição Patológica/terapia , Progressão da Doença , Feminino , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/mortalidade , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/mortalidade , Irlanda , Estimativa de Kaplan-Meier , Masculino , Veias Pulmonares/anormalidades , Veias Pulmonares/patologia , Pneumopatia Veno-Oclusiva/etiologia , Estudos Retrospectivos , Suécia , Resultado do Tratamento , Reino Unido
16.
Ultrasound Obstet Gynecol ; 29(6): 628-33, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17476706

RESUMO

OBJECTIVE: Prenatal diagnosis of isolated coarctation of the aorta suffers from high false positive and false negative rates. The aim of our study was to develop Z-scores for the aortic isthmus in normal fetuses as a reference for fetuses with suspected coarctation. METHODS: The aortic isthmal diameter, immediately proximal to the insertion of the arterial duct, was measured prospectively in the transverse (three vessel and trachea) and sagittal views in 221 normal fetuses at 18 to 37 weeks' gestation. The ductal diameter was measured immediately before it entered the descending aorta in the same view. All measurements were repeated three times by a single investigator and averaged. A second investigator re-measured the images of 50 cases to assess interobserver variability. Z-scores were created relating isthmal and ductal diameters to femur length and gestational age. The ratio between the isthmal and ductal diameters was calculated. RESULTS: The formula used to calculate Z-scores for the three diameters was: [ln(measured isthmal diameter) - (m ln(femur length or gestational age) + c)]/root MSE, where c is the intercept, m is a multiplier and MSE is the mean squared error. The ratio between isthmal and ductal diameters was close to a constant value of 1 (95% CI 0.97-1.01), regardless of the value of femur length or gestational age. CONCLUSION: We have defined Z-scores for the fetal aortic isthmus and arterial duct measured in the three vessels and trachea view and for the isthmus in the sagittal plane. In suspected coarctation, these Z-scores and the isthmal to ductal ratio may help in longitudinal assessment of the aortic arch and aid in the prenatal diagnosis of coarctation.


Assuntos
Aorta Torácica/diagnóstico por imagem , Ecocardiografia/normas , Coração Fetal/diagnóstico por imagem , Cardiopatias Congênitas/diagnóstico por imagem , Ultrassonografia Pré-Natal/normas , Aorta Torácica/embriologia , Canal Arterial/diagnóstico por imagem , Feminino , Idade Gestacional , Cardiopatias Congênitas/embriologia , Humanos , Gravidez , Diagnóstico Pré-Natal/normas , Estudos Prospectivos , Valores de Referência , Reprodutibilidade dos Testes
17.
Gen Comp Endocrinol ; 145(3): 222-31, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16242686

RESUMO

In most teleost fishes, prolactin (PRL) plays a key role in freshwater (FW) adaptation, whereas growth hormone (GH) is involved in seawater (SW) adaptation in salmonids and certain euryhaline species including the tilapia, Oreochromis mossambicus. Consistent with its osmoregulatory activity, PRL release increases in response to physiologically relevant reductions in extracellular osmolality. When dispersed PRL and GH cells from FW-acclimatized fish were incubated in media of varying osmolalities, PRL release increased significantly in response to a 12% reduction in medium osmolality during 1 and 4h of exposure. By contrast, cells from SW-acclimatized fish responded only to a 24% reduction in osmolality. Growth hormone release on the other hand increased whether medium osmolality was reduced or raised. Cell volume increased together with PRL release during the perifusion of dispersed PRL cells in direct proportion to the reduction in medium osmolality. Growth hormone release increased whether GH cell volume increased or decreased. In in vivo studies, circulating PRL levels increased as early as 1h after the transfer of fish from SW to FW, whereas GH levels remained unchanged during 24h of acclimatization. These results indicate that while PRL and GH cells are osmosensitive, the PRL cells respond to reductions in extracellular osmolality in a manner that is consistent with PRL's physiological role in the tilapia. While the rise in GH release following the reduction in osmolality is of uncertain physiological significance, the rise in GH release with the elevation of medium osmolality may be connected to its role in SW adaptation.


Assuntos
Hormônio do Crescimento/metabolismo , Hipófise/metabolismo , Prolactina/metabolismo , Tilápia/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Animais , Cálcio/metabolismo , Tamanho Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Proteínas de Peixes/sangue , Proteínas de Peixes/metabolismo , Hormônio do Crescimento/sangue , Soluções Hipertônicas/farmacologia , Soluções Hipotônicas/farmacologia , Masculino , Concentração Osmolar , Hipófise/citologia , Hipófise/efeitos dos fármacos , Prolactina/sangue
18.
Heart ; 92(6): 815-20, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16278274

RESUMO

OBJECTIVE: To determine the safety and effectiveness of cutting balloon angioplasty for pulmonary vein stenosis (PVS). DESIGN AND SETTING: Retrospective review of case notes and cardiac catheterisation data at the Royal Brompton Hospital. MAIN OUTCOME MEASURES: Diameter of pulmonary vein, tricuspid regurgitant jet velocity on echocardiogram, and percutaneous oxygen saturation before and after cutting balloon angioplasty. RESULTS: Three patients had congenital PVS and three had PVS associated with total anomalous pulmonary venous drainage. A total of 27 PVSs were treated during 12 catheterisation procedures. Median patient age at the time of procedure was 12.5 months (range 1.5-36 months) and weight was 7.1 kg (range 2.8-11.1 kg). Minimum pulmonary vein diameter increased significantly on angiography after cutting balloon angioplasty, from mean (SD) 2.3 (0.7) mm to 4.2 (1.9) mm, mean of differences 1.9 mm (95% confidence interval (CI) 0.9 to 2.9 mm, p = 0.0013). Mean (SD) oxygen saturation rose from 79.6 (12.9)% to 83.9 (9.0)%, mean of differences 4.3% (95% CI 0.7% to 8.0%, p = 0.0238). All children's symptoms improved subjectively. Tricuspid regurgitant jet velocity did not change significantly. The longest time interval before repeat intervention was six months. There were no acute deaths; one patient had a small pulmonary haemorrhage and developed a small aneurysm adjacent to the site of angioplasty. CONCLUSION: Cutting balloon angioplasty is safe in the palliation of PVS in children. It gives some acute relief but often needs to be repeated, as improvement is rarely sustained.


Assuntos
Angioplastia com Balão/métodos , Pneumopatia Veno-Oclusiva/terapia , Angioplastia com Balão/efeitos adversos , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Estudos Retrospectivos , Resultado do Tratamento
19.
Am J Physiol Cell Physiol ; 284(5): C1280-9, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12540379

RESUMO

In the tilapia (Oreochromis mossambicus), as in many euryhaline teleost fish, prolactin (PRL) plays a central role in freshwater adaptation, acting on osmoregulatory surfaces to reduce ion and water permeability and increase solute retention. Consistent with these actions, PRL release is stimulated as extracellular osmolality is reduced both in vivo and in vitro. In the current experiments, a perfusion system utilizing dispersed PRL cells was developed for permitting the simultaneous measurement of cell volume and PRL release. Intracellular Ca(2+) was monitored using fura 2-loaded cells under the same conditions. When PRL cells were exposed to hyposmotic medium, an increase in PRL cell volume preceded the increase in PRL release. Cell volume increased in proportion to decreases of 15 and 30% in osmolality. However, regulatory volume decrease was clearly seen only after a 30% reduction. The hyposmotically induced PRL release was sharply reduced in Ca(2+)-deleted hyposmotic medium, although cell volume changes were identical to those observed in normal hyposmotic medium. In most cells, a rise in intracellular Ca(2+) concentration ([Ca(2+)](i)) during hyposmotic stimulation was dependent on the availability of extracellular Ca(2+), although small transient increases in [Ca(2+)](i) were sometimes observed upon introduction of Ca(2+)-deleted media of the same or reduced osmolality. These results indicate that an increase in cell size is a critical step in the transduction of an osmotic signal into PRL release and that the hyposmotically induced increase in PRL release is greatly dependent on extracellular Ca(2+).


Assuntos
Cálcio/metabolismo , Espaço Extracelular/metabolismo , Hipófise/citologia , Hipófise/metabolismo , Prolactina/metabolismo , Tilápia/metabolismo , Animais , Tamanho Celular , Membranas Intracelulares/metabolismo , Oscilometria , Concentração Osmolar
20.
Am J Physiol Cell Physiol ; 284(5): C1290-6, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12540380

RESUMO

Prolactin (PRL) plays a central role in the freshwater osmoregulation of teleost fish, including the tilapia (Oreochromis mossambicus). Consistent with this action, PRL release from the tilapia pituitary increases as extracellular osmolality is reduced both in vitro and in vivo. Dispersed tilapia PRL cells were incubated in a perfusion chamber that allowed simultaneous measurements of cell volume and PRL release. Intracellular Ca(2+) concentrations were measured from fura 2-loaded PRL cells treated in a similar way. Gadolinium (Gd(3+)), known to block stretch-activated cation channels, inhibited hyposmotically induced PRL release in a dose-related manner without preventing cell swelling. Nifedipine, an L-type Ca(2+) channel blocker, did not prevent the increase in PRL release during hyposmotic stimulation. A high, depolarizing concentration of KCl induced a transient and marked increase of intracellular Ca(2+) and release of PRL but did not prevent the rise in intracellular Ca(2+) and PRL release evoked by exposure to hyposmotic medium. These findings suggest that a decrease in extracellular osmolality stimulates PRL release through the opening of stretch-activated ion channels, which allow extracellular Ca(2+) to enter the cell when it swells.


Assuntos
Canais Iônicos/fisiologia , Hipófise/fisiologia , Transdução de Sinais/fisiologia , Tilápia/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Animais , Cálcio/metabolismo , Tamanho Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Gadolínio/farmacologia , Membranas Intracelulares/metabolismo , Nifedipino/farmacologia , Concentração Osmolar , Estimulação Física , Hipófise/citologia , Hipófise/efeitos dos fármacos , Potássio/administração & dosagem , Prolactina/metabolismo
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