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1.
Ultrasound Obstet Gynecol ; 55(6): 730-739, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31273862

RESUMO

OBJECTIVE: The Management of Myelomeningocele Study (MOMS) trial demonstrated the safety and efficacy of open fetal surgery for spina bifida aperta (SBA). Recently developed alternative techniques may reduce maternal risks without compromising the fetal neuroprotective effects. The aim of this systematic review was to assess the learning curve (LC) of different fetal SBA closure techniques. METHODS: MEDLINE, Web of Science, EMBASE, Scopus and Cochrane databases and the gray literature were searched to identify relevant articles on fetal surgery for SBA, without language restriction, published between January 1980 and October 2018. Identified studies were reviewed systematically and those reporting all consecutive procedures and with postnatal follow-up ≥ 12 months were selected. Studies were included only if they reported outcome variables necessary to measure the LC, as defined by fetal safety and efficacy. Two authors independently retrieved data, assessed the quality of the studies and categorized observations into blocks of 30 patients. For meta-analysis, data were pooled using a random-effects model when heterogeneous. To measure the LC, we used two complementary methods. In the group-splitting method, competency was defined when the procedure provided results comparable to those in the MOMS trial for 12 outcome variables representing the immediate surgical outcome, short-term neonatal neuroprotection and long-term neuroprotection at ≥ 12 months of age. Then, when raw patient data were available, we performed cumulative sum analysis based on a composite binary outcome defining successful surgery. The composite outcome combined four clinically relevant variables for safety (absence of extreme preterm delivery < 30 weeks, absence of fetal death ≤ 7 days after surgery) and efficacy (reversal of hindbrain herniation and absence of any neonatal treatment of dehiscence or cerebrospinal fluid leakage at the closure site). RESULTS: Of 6024 search results, 17 (0.3%) studies were included, all of which had low, moderate or unclear risk of bias. Fetal SBA closure was performed using standard hysterotomy (11 studies), mini-hysterotomy (one study) or fetoscopy by either exteriorized-uterus single-layer closure (one study), percutaneous single-layer closure (three studies) or percutaneous two-layer closure (one study). Only outcomes for standard hysterotomy could be meta-analyzed. Overall, outcomes improved significantly with experience. Competency was reached after 35 consecutive cases for standard hysterotomy and was predicted to be achieved after ≥ 57 cases for mini-hysterotomy and ≥ 56 for percutaneous two-layer fetoscopy. For percutaneous and exteriorized-uterus single-layer fetoscopy, competency was not reached in the 81 and 28 cases available for analysis, respectively, and LC prediction analysis could not be performed. CONCLUSIONS: The number of cases operated is correlated with the outcome of fetal SBA closure, and the number of operated cases required to reach competency ranges from 35 for standard hysterotomy to ≥ 56-57 for minimally invasive modifications. Our observations provide important information for institutions looking to establish a new fetal center, develop a new fetal surgery technique or train their team, and inform referring clinicians, potential patients and third parties. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Curvas de aprendizaje del cierre de la espina bífida fetal mediante cirugía abierta y endoscópica: revisión sistemática y metaanálisis OBJETIVO: El ensayo del Estudio sobre la Gestión del Mielomeningocele (MOMS, por sus siglas en inglés) demostró la seguridad y eficacia de la cirugía fetal abierta para la espina bífida aperta (EBA). Las técnicas alternativas recientemente desarrolladas pueden reducir los riesgos de la madre sin comprometer los efectos neuroprotectores del feto. El objetivo de esta revisión sistemática fue evaluar la curva de aprendizaje (CA) de diferentes técnicas de cierre de la EBA fetal. MÉTODOS: Se realizaron búsquedas en las bases de datos de MEDLINE, Web of Science, EMBASE, Scopus y Cochrane, así como en la literatura gris, para identificar artículos relevantes sobre cirugía fetal para la EBA, sin restricción de idioma, publicados entre enero de 1980 y octubre de 2018. Se examinaron sistemáticamente los estudios identificados y se seleccionaron los que informaban de todos los procedimientos consecutivos y con seguimiento postnatal ≥12 meses. Los estudios se incluyeron sólo si informaban sobre las variables de resultado necesarias para medir la CA, definidas por la seguridad y la eficacia para el feto. Dos autores recuperaron los datos de forma independiente, evaluaron la calidad de los estudios y clasificaron las observaciones en bloques de 30 pacientes. Para el metaanálisis, los datos se agruparon mediante un modelo de efectos aleatorios cuando fueron heterogéneos. Para medir la CA, se usaron dos métodos complementarios. En el método de división de grupos, la competencia se definió cuando el procedimiento proporcionó resultados comparables a los del ensayo MOMS para 12 variables de resultados que representaban el resultado quirúrgico inmediato, la neuroprotección neonatal a corto plazo y la neuroprotección a largo plazo a ≥12 meses de edad. Luego, cuando se dispuso de los datos brutos de los pacientes, se realizó un análisis de suma acumulada basado en un resultado binario compuesto que definió el éxito de la cirugía. El resultado compuesto combinó cuatro variables clínicamente relevantes en cuanto a la seguridad (ausencia de parto pretérmino extremo <30 semanas; ausencia de muerte fetal a ≤7 días después de la cirugía) y eficacia (reducción de la hernia del rombencéfalo y ausencia de cualquier tratamiento neonatal de dehiscencia o derrame de líquido cefalorraquídeo en el lugar del cierre). RESULTADOS: De los 6024 resultados de la búsqueda, se incluyeron 17 (0,3%) estudios, todos ellos con un riesgo de sesgo bajo, moderado o incierto. El cierre de la EBA fetal se realizó mediante histerotomía estándar (11 estudios), mini histerotomía (un estudio) o fetoscopia, ya fuera mediante el cierre exteriorizado del útero de una sola capa (un estudio), el cierre percutáneo de una sola capa (tres estudios) o el cierre percutáneo de dos capas (un estudio). Sólo se pudieron metaanalizar los resultados de la histerotomía estándar. En general, los resultados mejoraron significativamente con la experiencia. Se alcanzó la competencia después de 35 casos consecutivos para la histerotomía estándar y se predijo que se alcanzaría después de ≥57 casos para la mini histerotomía y ≥56 para la fetoscopia percutánea de dos capas. En el caso de las fetoscopias percutánea y exteriorizada del útero de una sola capa, no se alcanzó la competencia en los 81 y 28 casos disponibles para el análisis, respectivamente, y no se pudo realizar el análisis de predicción de la CA. CONCLUSIONES: El número de casos operados está correlacionado con el resultado del cierre de la EBA fetal, y el número de casos operados necesarios para alcanzar la competencia estuvo entre 35 para la histerotomía estándar y ≥56-57 para las operaciones con mínima agresividad. Las observaciones realizadas proporcionan información importante para las instituciones que buscan establecer un nuevo centro fetal, desarrollar una nueva técnica de cirugía fetal o entrenar a su equipo, e informar a los médicos que remiten a especialistas a los posibles pacientes y a terceros. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Fetoscopia/educação , Feto/cirurgia , Histerotomia/educação , Espinha Bífida Cística/cirurgia , Adulto , Feminino , Humanos , Curva de Aprendizado , Gravidez , Espinha Bífida Cística/embriologia
3.
Neuroimage ; 82: 273-83, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23707588

RESUMO

INTRODUCTION: We performed a whole-transcriptome correlation analysis, followed by the pathway enrichment and testing of innate immune response pathway analyses to evaluate the hypothesis that transcriptional activity can predict cortical gray matter thickness (GMT) variability during normal cerebral aging. METHODS: Transcriptome and GMT data were available for 379 individuals (age range=28-85) community-dwelling members of large extended Mexican American families. Collection of transcriptome data preceded that of neuroimaging data by 17 years. Genome-wide gene transcriptome data consisted of 20,413 heritable lymphocytes-based transcripts. GMT measurements were performed from high-resolution (isotropic 800 µm) T1-weighted MRI. Transcriptome-wide and pathway enrichment analysis was used to classify genes correlated with GMT. Transcripts for sixty genes from seven innate immune pathways were tested as specific predictors of GMT variability. RESULTS: Transcripts for eight genes (IGFBP3, LRRN3, CRIP2, SCD, IDS, TCF4, GATA3, and HN1) passed the transcriptome-wide significance threshold. Four orthogonal factors extracted from this set predicted 31.9% of the variability in the whole-brain and between 23.4 and 35% of regional GMT measurements. Pathway enrichment analysis identified six functional categories including cellular proliferation, aggregation, differentiation, viral infection, and metabolism. The integrin signaling pathway was significantly (p<10(-6)) enriched with GMT. Finally, three innate immune pathways (complement signaling, toll-receptors and scavenger and immunoglobulins) were significantly associated with GMT. CONCLUSION: Expression activity for the genes that regulate cellular proliferation, adhesion, differentiation and inflammation can explain a significant proportion of individual variability in cortical GMT. Our findings suggest that normal cerebral aging is the product of a progressive decline in regenerative capacity and increased neuroinflammation.


Assuntos
Envelhecimento/genética , Envelhecimento/patologia , Córtex Cerebral/patologia , Transcriptoma , Adulto , Idoso , Idoso de 80 Anos ou mais , Córtex Cerebral/metabolismo , Perfilação da Expressão Gênica , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade
4.
Mol Psychiatry ; 16(11): 1096-104, 1063, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21483430

RESUMO

Although disrupted in schizophrenia 1 (DISC1) has been implicated in many psychiatric disorders, including schizophrenia, bipolar disorder, schizoaffective disorder and major depression, its biological role in these disorders is unclear. To better understand this gene and its role in psychiatric disease, we conducted transcriptional profiling and genome-wide association analysis in 1232 pedigreed Mexican-American individuals for whom we have neuroanatomic images, neurocognitive assessments and neuropsychiatric diagnoses. SOLAR was used to determine heritability, identify gene expression patterns and perform association analyses on 188 quantitative brain-related phenotypes. We found that the DISC1 transcript is highly heritable (h(2)=0.50; P=1.97 × 10(-22)), and that gene expression is strongly cis-regulated (cis-LOD=3.89) but is also influenced by trans-effects. We identified several DISC1 polymorphisms that were associated with cortical gray matter thickness within the parietal, temporal and frontal lobes. Associated regions affiliated with memory included the entorhinal cortex (rs821639, P=4.11 × 10(-5); rs2356606, P=4.71 × 10(-4)), cingulate cortex (rs16856322, P=2.88 × 10(-4)) and parahippocampal gyrus (rs821639, P=4.95 × 10(-4)); those affiliated with executive and other cognitive processing included the transverse temporal gyrus (rs9661837, P=5.21 × 10(-4); rs17773946, P=6.23 × 10(-4)), anterior cingulate cortex (rs2487453, P=4.79 × 10(-4); rs3738401, P=5.43 × 10(-4)) and medial orbitofrontal cortex (rs9661837; P=7.40 × 10(-4)). Cognitive measures of working memory (rs2793094, P=3.38 × 10(-4)), as well as lifetime history of depression (rs4658966, P=4.33 × 10(-4); rs12137417, P=4.93 × 10(-4)) and panic (rs12137417, P=7.41 × 10(-4)) were associated with DISC1 sequence variation. DISC1 has well-defined genetic regulation and clearly influences important phenotypes related to psychiatric disease.


Assuntos
Córtex Cerebral/anatomia & histologia , Cognição/fisiologia , Depressão/genética , Proteínas do Tecido Nervoso/genética , Transtorno de Pânico/genética , Polimorfismo Genético , Córtex Cerebral/química , Depressão/etnologia , Depressão/fisiopatologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Entrevista Psicológica , Linfócitos/química , Memória de Curto Prazo/fisiologia , Americanos Mexicanos/genética , Americanos Mexicanos/psicologia , Repetições de Microssatélites , Proteínas do Tecido Nervoso/fisiologia , Testes Neuropsicológicos , Transtorno de Pânico/etnologia , Transtorno de Pânico/fisiopatologia , Fenótipo , Polimorfismo de Nucleotídeo Único , RNA Mensageiro/biossíntese , Estudos de Amostragem , Texas/epidemiologia , Transcrição Gênica
5.
Acta Psychiatr Scand ; 126(2): 87-105, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22486607

RESUMO

OBJECTIVE: To develop effective interventions for people with coexisting mental disorders (MD) and substance use, it may be beneficial to understand their attitudes and perceptions of substances. METHOD: A systematic literature search regarding attitudes and perceptions towards tobacco, alcohol or cannabis among people with MD was conducted. Studies' methodological quality was assessed using the Newcastle-Ottawa Scale. RESULTS: Twenty-one papers were included in the review and found to have generally low methodological quality. Papers investigated reasons for substance use, substance use expectancies, substances' perceived effects and reasons for quitting. People with psychotic disorders reported using substances primarily for relaxation and pleasure. Among people with mood disorders, alcohol was used primarily for social motives and tobacco for negative affect reduction. CONCLUSION: For substance use interventions among people with MD to be more effective, it may be necessary to tailor interventions specifically for this population and customize by substance type. Gaps in the literature regarding attitudes and perceptions towards substance use among people with MD were identified, which future research should aim to address. These include designing and conducting methodologically rigorous research, investigating perceived harmfulness and knowledge of substances, and broadening recruitment of participants to include people with MD other than psychosis.


Assuntos
Atitude Frente a Saúde , Transtornos Mentais/psicologia , Transtornos Relacionados ao Uso de Substâncias/psicologia , Bebidas Alcoólicas , Alcoolismo/psicologia , Cannabis , Humanos , Abuso de Maconha/psicologia , Nicotiana , Tabagismo/psicologia
6.
Ultrasound Obstet Gynecol ; 40(3): 319-24, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22302774

RESUMO

OBJECTIVE: The application of radiofrequency ablation (RFA) termination procedures to complicated cases involving monochorionic twins offers the potential of a less invasive option when compared to endoscopic techniques. The purpose of this study was to compare outcomes between these two techniques. METHODS: A retrospective review was undertaken of all cases of complicated monochorionic twin gestations treated at the Children's Hospital of Philadelphia from July 1996 to December 2010. Cases were identified from the fetal treatment database and data extracted in a uniform fashion from the patients' charts. RESULTS: A total of 149 cases were identified with procedures performed on 146. Indications for selective termination of one fetus were twin reversed arterial perfusion sequence in 53, severe twin-to-twin transfusion syndrome in 43, discordance for fetal anomalies in 26 and selective intrauterine growth restriction in 24. Eighty-eight cases were managed with bipolar cord coagulation (BCC) and 58 with RFA. The procedures in all cases were technically successful in achieving selective termination. The mean gestational age at the time of the procedure was 20.9 ± 2.7 weeks in the BCC group vs 20.2 ± 2.2 weeks in the RFA group (P = 0.1). The median gestational age at delivery was 34.7 (interquartile range (IQR), 29.2-38.6) weeks for the BCC group vs 33.0 (IQR, 23.4-38.9) weeks in the RFA group (P = 0.073). Mean birth weight did not differ between the two groups. The procedure-to-delivery time was 87.1 ± 42.1 days for the BCC group vs 73.8 ± 47.2 days for the RFA group (P = 0.1). Overall survival was 85.2% in the BCC group vs 70.7% in the RFA group (P = 0.014). This was attributed primarily to a survival rate of 10.5% in the RFA group compared with 31.6% in the BCC group for cases where delivery occurred before 28 weeks' gestation (P = 0.01). Premature rupture of the membranes occurred in 27.3% in the BCC group vs 13.7% in the RFA group (P = 0.05). Preterm labor was more common in the BCC group than in the RFA group (22.4 vs 7%, respectively; P = 0.009). CONCLUSION: Despite the smaller caliber of the instrument, RFA is not associated with a decrease in the overall complication rate for selective termination procedures. The technique used for selective termination should still be determined by technical considerations but patients should be informed of the survival rate associated with each technique.


Assuntos
Ablação por Cateter/métodos , Parto Obstétrico/métodos , Redução de Gravidez Multifetal/métodos , Gravidez de Gêmeos , Cordão Umbilical/cirurgia , Feminino , Idade Gestacional , Humanos , Philadelphia , Gravidez , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
7.
AJNR Am J Neuroradiol ; 43(7): 978-983, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35772803

RESUMO

BACKGROUND AND PURPOSE: Diagnosing spontaneous intracranial hypotension and associated CSF leaks can be challenging, and additional supportive imaging findings would be useful to direct further evaluation. This retrospective study evaluated whether there was a difference in the prevalence of calvarial hyperostosis in a cohort of patients with spontaneous intracranial hypotension compared with an age- and sex-matched control population. MATERIALS AND METHODS: Cross-sectional imaging (CT of the head or brain MR imaging examinations) for 166 patients with spontaneous intracranial hypotension and 321 matched controls was assessed by neuroradiologists blinded to the patient's clinical status. The readers qualitatively evaluated the presence of diffuse or layered calvarial hyperostosis and measured calvarial thickness in the axial and coronal planes. RESULTS: A significant difference in the frequency of layered hyperostosis (31.9%, 53/166 subjects versus 5.0%, 16/321 controls, P < .001, OR = 11.58) as well as the frequency of overall (layered and diffuse) hyperostosis (38.6%, 64/166 subjects versus 13.2%, 42/321 controls, P < .001, OR = 4.66) was observed between groups. There was no significant difference in the frequency of diffuse hyperostosis between groups (6.6%, 11/166 subjects versus 8.2%, 26/321 controls, P = .465). A significant difference was also found between groups for calvarial thickness measured in the axial (P < .001) and coronal (P < .001) planes. CONCLUSIONS: Layered calvarial hyperostosis is more prevalent in spontaneous intracranial hypotension compared with the general population and can be used as an additional noninvasive brain imaging marker of spontaneous intracranial hypotension and an underlying spinal CSF leak.


Assuntos
Hiperostose , Hipotensão Intracraniana , Estudos de Casos e Controles , Vazamento de Líquido Cefalorraquidiano , Anormalidades Craniofaciais , Humanos , Hiperostose/diagnóstico por imagem , Hipotensão Intracraniana/complicações , Hipotensão Intracraniana/diagnóstico por imagem , Hipotensão Intracraniana/epidemiologia , Imageamento por Ressonância Magnética/métodos , Mielografia/métodos , Estudos Retrospectivos
8.
Mol Hum Reprod ; 17(7): 439-46, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21355050

RESUMO

The etiology of preeclampsia is complex, with susceptibility being attributable to multiple environmental factors and a large genetic component. Although many candidate genes for preeclampsia have been suggested and studied, the specific causative genes still remain to be identified. Catechol-O-methyltransferase (COMT) is an enzyme involved in catecholamine and estrogen degradation and has recently been ascribed a role in development of preeclampsia. In the present study, we have examined the COMT gene by genotyping the functional Val108/158Met polymorphism (rs4680) and an additional single-nucleotide polymorphism, rs6269, predicting COMT activity haplotypes in a large Norwegian case/control cohort (n(cases)= 1135, n(controls)= 2262). A low COMT activity haplotype is associated with recurrent preeclampsia in our cohort. This may support the role of redox-regulated signaling and oxidative stress in preeclampsia pathogenesis as suggested by recent studies in a genetic mouse model. The COMT gene might be a genetic risk factor shared between preeclampsia and cardiovascular diseases.


Assuntos
Catecol O-Metiltransferase/genética , Haplótipos/genética , Pré-Eclâmpsia/genética , Feminino , Predisposição Genética para Doença , Humanos , Noruega , Gravidez , População Branca
9.
Heredity (Edinb) ; 106(1): 78-87, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20424639

RESUMO

Reliable population DNA molecular markers are difficult to develop for molluscs, the reasons for which are largely unknown. Identical protocols for microsatellite marker development were implemented in three gastropods. Success rates were lower for Gibbula cineraria compared to Littorina littorea and L. saxatilis. Comparative genomic analysis of 47.2 kb of microsatellite containing sequences (MCS) revealed a high incidence of cryptic repetitive DNA in their flanking regions. The majority of these were novel, and could be grouped into DNA families based upon sequence similarities. Significant inter-specific variation in abundance of cryptic repetitive DNA and DNA families was observed. Repbase scans show that a large proportion of cryptic repetitive DNA was identified as transposable elements (TEs). We argue that a large number of TEs and their transpositional activity may be linked to differential rates of DNA multiplication and recombination. This is likely to be an important factor explaining inter-specific variation in genome stability and hence microsatellite marker development success rates. Gastropods also differed significantly in the type of TEs classes (autonomous vs non-autonomous) observed. We propose that dissimilar transpositional mechanisms differentiate the TE classes in terms of their propensity for transposition, fixation and/or silencing. Consequently, the phylogenetic conservation of non-autonomous TEs, such as CvA, suggests that dispersal of these elements may have behaved as microsatellite-inducing elements. Results seem to indicate that, compared to autonomous, non-autonomous TEs maybe have a more active role in genome rearrangement processes. The implications of the findings for genomic rearrangement, stability and marker development are discussed.


Assuntos
Gastrópodes/crescimento & desenvolvimento , Gastrópodes/genética , Variação Genética , Repetições de Microssatélites/genética , Animais , Hibridização Genômica Comparativa , Marcadores Genéticos/genética , Especificidade da Espécie
10.
Mol Hum Reprod ; 16(12): 960-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20643876

RESUMO

Variation in the Storkhead box-1 (STOX1) gene has previously been associated with pre-eclampsia. In this study, we assess candidate single nucleotide polymorphisms (SNPs) in STOX1 in an independent population cohort of pre-eclamptic (n = 1.139) and non-pre-eclamptic (n = 2.269) women (the HUNT2 study). We also compare gene expression levels of STOX1 and its paralogue, Storkhead box-2 (STOX2) in decidual tissue from pregnancies complicated by pre-eclampsia and/or fetal growth restriction (FGR) (n = 40) to expression levels in decidual tissue from uncomplicated pregnancies (n = 59). We cannot confirm association of the candidate SNPs to pre-eclampsia (P > 0.05). For STOX1, no differential gene expression was observed in any of the case groups, whereas STOX2 showed significantly lower expression in deciduas from pregnancies complicated by both pre-eclampsia and FGR as compared with controls (P = 0.01). We further report a strong correlation between transcriptional alterations reported previously in choriocarcinoma cells over expressing STOX1A and alterations observed in decidual tissue of pre-eclamptic women with FGR.


Assuntos
Proteínas de Transporte/genética , Decídua/metabolismo , Pré-Eclâmpsia/metabolismo , Adulto , Proteínas de Transporte/metabolismo , Proteínas de Transporte/fisiologia , Estudos de Coortes , Feminino , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/metabolismo , Expressão Gênica , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Pré-Eclâmpsia/genética , Gravidez
11.
Osteoarthritis Cartilage ; 18(11): 1536-43, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20863899

RESUMO

OBJECTIVE: The present study examined whether local administration of the cannabinoid-2 (CB(2)) receptor agonist GW405833 could modulate joint nociception in control rat knee joints and in an animal model of osteoarthritis (OA). METHOD: OA was induced in male Wistar rats by intra-articular injection of sodium monoiodo-acetate with a recovery period of 14 days. Immunohistochemistry was used to evaluate the expression of CB(2) and transient receptor potential vanilloid channel-1 (TRPV1) receptors in the dorsal root ganglion (DRG) and synovial membrane of sham- and sodium mono-iodoacetate (MIA)-treated animals. Electrophysiological recordings were made from knee joint primary afferents in response to rotation of the joint both before and following close intra-arterial injection of different doses of GW405833. The effect of intra-articular GW405833 on joint pain perception was determined by hindlimb incapacitance. An in vitro neuronal release assay was used to see if GW405833 caused release of an inflammatory neuropeptide (calcitonin gene-related peptide - CGRP). RESULTS: CB(2) and TRPV1 receptors were co-localized in DRG neurons and synoviocytes in both sham- and MIA-treated animals. Local application of the GW405833 significantly reduced joint afferent firing rate by up to 31% in control knees. In OA knee joints, however, GW405833 had a pronounced sensitising effect on joint mechanoreceptors. Co-administration of GW405833 with the CB(2) receptor antagonist AM630 or pre-administration of the TRPV1 ion channel antagonist SB366791 attenuated the sensitising effect of GW405833. In the pain studies, intra-articular injection of GW405833 into OA knees augmented hindlimb incapacitance, but had no effect on pain behaviour in saline-injected control joints. GW405833 evoked increased CGRP release via a TRPV1 channel-dependent mechanism. CONCLUSION: These data indicate that GW405833 reduces the mechanosensitivity of afferent nerve fibres in control joints but causes nociceptive responses in OA joints. The observed pro-nociceptive effect of GW405833 appears to involve TRPV1 receptors.


Assuntos
Indóis/farmacologia , Articulação do Joelho/efeitos dos fármacos , Morfolinas/farmacologia , Osteoartrite do Joelho/complicações , Dor/tratamento farmacológico , Receptor CB2 de Canabinoide/agonistas , Animais , Canabinoides/análise , Modelos Animais de Doenças , Eletrofisiologia , Gânglios Espinais/metabolismo , Imuno-Histoquímica , Injeções Intra-Articulares , Articulação do Joelho/fisiologia , Masculino , Fibras Nervosas/efeitos dos fármacos , Fibras Nervosas/fisiologia , Osteoartrite do Joelho/metabolismo , Dor/etiologia , Ratos , Ratos Wistar , Membrana Sinovial/metabolismo , Canais de Cátion TRPV/análise
12.
Ultrasound Obstet Gynecol ; 36(6): 682-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20503245

RESUMO

OBJECTIVE: Lower urinary tract obstruction (LUTO) with massive bladder distension impacts on a variety of developing organ systems with consequent morbidity and mortality. The impact of LUTO on the fetal cardiovascular system has not previously been investigated. We hypothesize that a giant, distended bladder within the pelvis may cause vascular compression with observable consequences. METHODS: Fetal echocardiography was performed in 42 fetuses with LUTO and compared with 35 normal controls matched for gestational age. Parameters investigated included cardiothoracic ratio, presence or absence of ventricular hypertrophy and pericardial effusion. Doppler echocardiographic examination of mitral and tricuspid valve inflow and the ductus venosus was performed. To assess arterial vascular impedance, pulsatility indices (PIs) were calculated for segments of the descending aorta and right and left iliac arteries (RIA and LIA). RESULTS: In the LUTO group an increased cardiothoracic ratio was seen in nine (21%), ventricular hypertrophy in 12 (29%) and small pericardial effusion in 15 (36%). Filling characteristics of the right ventricle in the LUTO group demonstrated greater dependency upon atrial contraction, and ductus venosus flow demonstrated higher downstream impedance to filling, than in controls, suggesting altered compliance. The LUTO group also had lower distal descending aorta PI (1.53 ± 0.38 vs. 1.76 ± 0.44, P = 0.04), lower RIA-PI (1.31 ± 0.29 vs. 1.76 ± 0.44, P < 0.001) and lower LIA-PI (1.41 ± 0.44 vs. 1.73 ± 0.31, P < 0.01) than controls, suggesting vascular compression and increased impedance to flow. CONCLUSIONS: LUTO with giant urinary bladder compresses the iliac arteries, which may lead to increased afterload. Further study is warranted to examine the impact of fetal treatment such as bladder drainage on these cardiovascular parameters.


Assuntos
Doenças Cardiovasculares/diagnóstico por imagem , Coração Fetal/diagnóstico por imagem , Obstrução Uretral/diagnóstico por imagem , Doenças da Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo/fisiologia , Doenças Cardiovasculares/embriologia , Doenças Cardiovasculares/etiologia , Ecocardiografia Doppler , Feminino , Coração Fetal/fisiopatologia , Idade Gestacional , Humanos , Gravidez , Ultrassonografia Pré-Natal , Obstrução Uretral/complicações , Obstrução Uretral/embriologia , Bexiga Urinária/irrigação sanguínea , Bexiga Urinária/embriologia , Doenças da Bexiga Urinária/embriologia , Doenças da Bexiga Urinária/fisiopatologia
13.
Ultrasound Obstet Gynecol ; 36(1): 48-51, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20201111

RESUMO

OBJECTIVE: To determine pregnancy outcomes of patients who present with Stage I twin-to-twin transfusion syndrome (TTTS). METHODS: This was a retrospective review of all patients with TTTS referred to our institution between January 2005 and December 2006. Quintero criteria were used for staging. Laser ablation was not offered to patients with Stage I disease. RESULTS: A total of 155 twin pregnancies were evaluated for TTTS during this period. Forty-two met the criteria for Stage I and were included in the analysis. The overall survival to discharge was 82%. The mean gestational age at the time of consultation was 20.9 +/- 0.4 weeks. A total of 23 cases (54.8%) underwent amnioreduction. Progression of TTTS requiring invasive therapy occurred in four cases. The mean gestational age at delivery was 32.5 +/- 0.62 weeks. When divided according to use of amnioreduction, there were no statistically significant differences between the groups for gestational age at delivery or for birth weight. Those Stage I cases with a CHOP cardiovascular score of 5 or higher delivered almost 3 weeks earlier than the remainder of the cohort. CONCLUSIONS: Progression of TTTS beyond Stage I occurred in only 9.5% of the cohort. Mean gestational age at delivery and survival to discharge did not differ between Stage I patients and those treated with placental laser ablation for more advanced stages of TTTS.


Assuntos
Transfusão Feto-Fetal/mortalidade , Resultado da Gravidez , Adulto , Peso ao Nascer , Progressão da Doença , Feminino , Transfusão Feto-Fetal/diagnóstico por imagem , Transfusão Feto-Fetal/patologia , Idade Gestacional , Humanos , Gravidez , Estudos Retrospectivos , Índice de Gravidade de Doença , Taxa de Sobrevida , Gêmeos , Ultrassonografia
14.
Ultrasound Obstet Gynecol ; 36(4): 465-70, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20499409

RESUMO

OBJECTIVES: To review our experience with the prenatal diagnosis of hypoplastic left heart syndrome (HLHS). Our goal was to establish the benchmark for perinatal and early surgical outcome in the current era, from a center with an aggressive surgical approach and a cohort with a high level of intention-to-treat. METHODS: Outcome was assessed in fetuses with HLHS following stratification into high-risk and standard-risk categories. High risk was defined as the presence of any of the following: extracardiac, genetic or chromosomal anomalies; prematurity of < 34 weeks' gestation; additional cardiac findings such as intact or highly restrictive atrial septum, severe degree of tricuspid regurgitation or severe ventricular dysfunction. Standard risk was defined as absence of these risk factors. RESULTS: Of 240 fetuses evaluated over 5 years, 162 (67.5%) were in the standard-risk group and 78 (32.5%) were in the high-risk group. Of the 240 sets of parents, 38 (15.8%) chose termination or non-intervention at birth at initial prenatal counseling and 185 of the neonates (77.1%) underwent first-stage Norwood surgery with 155 surviving and 30 deaths, giving an overall Norwood operative survival of 83.8%. Breakdown by risk class reveals a significant Norwood operative survival advantage for the standard-risk group (92.8%) over the high-risk group (56.5%) (P < 0.001). CONCLUSIONS: Following prenatal diagnosis of HLHS, families should be strongly encouraged to undertake comprehensive prenatal evaluation in order to obtain an accurate prognosis. One-third have additional risk factors that limit survival outcome, however two-thirds do not and have an excellent chance of early survival.


Assuntos
Benchmarking , Procedimentos Cirúrgicos Cardíacos/mortalidade , Síndrome do Coração Esquerdo Hipoplásico/mortalidade , Procedimentos Cirúrgicos Cardíacos/normas , Feminino , Humanos , Síndrome do Coração Esquerdo Hipoplásico/diagnóstico por imagem , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Gravidez , Resultado da Gravidez , Diagnóstico Pré-Natal , Prognóstico , Fatores de Risco , Análise de Sobrevida , Ultrassonografia
15.
Disabil Rehabil Assist Technol ; 15(5): 537-544, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31012752

RESUMO

Purpose: Given the scarcity of service dogs to help individuals with mobility impairments in the community, it is crucial to identify facilitators and obstacles to the acquisition and use of service dogs in order to optimize their use and have a positive impact on the lives of individuals with disabilities. The goal of this study was to describe perceived facilitators and barriers influencing the acquisition and use of service dog by owners and rehabilitation providers, including those who had and had not recommended service dogs.Method: We conducted a phenomenological qualitative study involving in-depth interviews with nine service dog owners and 13 rehabilitation professionals in Canada. Our questionnaires were based on the Theoretical Domains Framework and the data were analyzed using a thematic content approach.Results: Knowledge, beliefs about consequences, and environmental context and resources were the domains most frequently mentioned by both dog owners and rehabilitation professionals. While service dog owners placed greater importance on their belief in their capacity to get and use service dogs, rehabilitation professionals focussed more on their role and identity within the process.Conclusion: Improving the knowledge of the availability and process of acquiring service dogs would be important for rehabilitation professions to improve the quality of life and functional capabilities of persons with disabilities.Implications for rehabilitationIdentifying determinants of service dog acquisition and use can support proposed strategies to optimize the use of this assistive technology;Determinants of service dog acquisition and use are are different for dog owners and rehabilitation professionals, which suggest the need of tailored knowledge translation strategies;Knowledge, beliefs about consequences, and environmental context and resources were the categories of determinants perceived as being more influential on the process.


Assuntos
Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Pessoas com Deficiência/reabilitação , Animais de Trabalho , Adulto , Animais , Cães , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Pesquisa Qualitativa , Qualidade de Vida , Inquéritos e Questionários
16.
Mol Hum Reprod ; 15(3): 195-204, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19126782

RESUMO

Pre-eclampsia is a common serious disorder of human pregnancy, which is associated with significant maternal and perinatal morbidity and mortality. The suspected aetiology of pre-eclampsia is complex, with susceptibility being attributable to multiple environmental factors and a large genetic component. Recently, we reported significant linkage to chromosome 2q22 in 34 Australian/New Zealand (Aust/NZ) pre-eclampsia/eclampsia families, and activin A receptor type IIA (ACVR2A) was identified as a strong positional candidate gene at this locus. In an attempt to identify the putative risk variants, we have now comprehensively re-sequenced the entire coding region of the ACVR2A gene and the conserved non-coding sequences in a subset of 16 individuals from these families. We identified 45 single nucleotide polymorphisms (SNPs), with 9 being novel. These SNPs were genotyped in our total family sample of 480 individuals from 74 Aust/NZ pre-eclampsia families (including the original 34 genome-scanned families). Our best associations between ACVR2A polymorphisms and pre-eclampsia were for rs10497025 (P = 0.025), rs13430086 (P = 0.010) and three novel SNPs: LF004, LF013 and LF020 (all with P = 0.018). After correction for multiple hypothesis testing, none of these associations reached significance (P > 0.05). Based on these data, it remains unclear what role, if any, ACVR2A polymorphisms play in pre-eclampsia risk, at least in these Australian families. However, it would be premature to rule out this gene as significant associations between ACVR2A SNPs and pre-eclampsia have recently been reported in a large Norwegian (HUNT) population sample.


Assuntos
Receptores de Activinas Tipo II/genética , Predisposição Genética para Doença/genética , Pré-Eclâmpsia/genética , Estudos de Coortes , Feminino , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , Gravidez
17.
J Cell Biol ; 97(4): 1038-42, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6194160

RESUMO

Our goal was to elucidate the pathway of newly synthesized phospholipid into the growing neurite. This was accomplished in pulse-chase studies with the phospholipid precursor [3H]glycerol, using sprouting explant cultures of rat superior cervical ganglion as an experimental system. After the pulse with the precursor and various chase periods, we separated perikarya and neurites microsurgically and extracted their phospholipids. The phospholipid extract from the perikarya exhibited a steep rise followed by a rapid decline in specific radioactivity. In contrast, an increase in neuritic specific radioactivity of phospholipid was observed only after a lag period of approximately 60 min. Nearly quantitative transfer of newly synthesized phospholipid from the perikarya into the neurites could be demonstrated. Both the decline in perikaryal specific radioactivity and the increase in its neuritic counterpart, i.e., the proximodistal transfer, could be blocked with the microtubule drug colchicine and the metabolic uncoupler, 2,4-dinitrophenol. These observations indicate preferential export of newly synthesized phospholipid from the perikaryon (the major or exclusive site of synthesis) into the growing neurites, most likely by rapid axoplasmic transport of formed elements.


Assuntos
Transporte Axonal , Axônios/metabolismo , Neurônios/metabolismo , Fosfolipídeos/metabolismo , 2,4-Dinitrofenol , Animais , Transporte Axonal/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Membrana Celular/metabolismo , Colchicina/farmacologia , Dinitrofenóis/farmacologia , Gânglios Simpáticos , Cinética , Neurônios/citologia , Ratos
18.
Science ; 179(4076): 893-5, 1973 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-17832770

RESUMO

Regression analyses to determine plant species number are repeated for the Galápagos Islands with new data. The multiple curvilinear regression gives the best prediction of species number, with island area making the only significant contribution. The proportion of species endemic to the Galápagos is highest in the arid, transition zone and on small islands, and lowest in the littoral and mesic zones. This is explained in terms of zone-specific immigration and extinction rates and the very recent appearance of moist upland climates in the archipelago.

19.
Nat Plants ; 5(8): 879-889, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31332310

RESUMO

Prochlorococcus is a major contributor to primary production, and globally the most abundant photosynthetic genus of picocyanobacteria because it can adapt to highly stratified low-nutrient conditions that are characteristic of the surface ocean. Here, we examine the structural adaptations of the photosynthetic thylakoid membrane that enable different Prochlorococcus ecotypes to occupy high-light, low-light and nutrient-poor ecological niches. We used atomic force microscopy to image the different photosystem I (PSI) membrane architectures of the MED4 (high-light) Prochlorococcus ecotype grown under high-light and low-light conditions in addition to the MIT9313 (low-light) and SS120 (low-light) Prochlorococcus ecotypes grown under low-light conditions. Mass spectrometry quantified the relative abundance of PSI, photosystem II (PSII) and cytochrome b6f complexes and the various Pcb proteins in the thylakoid membrane. Atomic force microscopy topographs and structural modelling revealed a series of specialized PSI configurations, each adapted to the environmental niche occupied by a particular ecotype. MED4 PSI domains were loosely packed in the thylakoid membrane, whereas PSI in the low-light MIT9313 is organized into a tightly packed pseudo-hexagonal lattice that maximizes harvesting and trapping of light. There are approximately equal levels of PSI and PSII in MED4 and MIT9313, but nearly twofold more PSII than PSI in SS120, which also has a lower content of cytochrome b6f complexes. SS120 has a different tactic to cope with low-light levels, and SS120 thylakoids contained hundreds of closely packed Pcb-PSI supercomplexes that economize on the extra iron and nitrogen required to assemble PSI-only domains. Thus, the abundance and widespread distribution of Prochlorococcus reflect the strategies that various ecotypes employ for adapting to limitations in light and nutrient levels.


Assuntos
Complexo de Proteína do Fotossistema I/metabolismo , Prochlorococcus/metabolismo , Membrana Celular/química , Membrana Celular/metabolismo , Luz , Espectrometria de Massas , Microscopia de Força Atômica , Fotossíntese , Complexo de Proteína do Fotossistema I/química , Conformação Proteica
20.
AJNR Am J Neuroradiol ; 40(11): 1855-1863, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31649155

RESUMO

BACKGROUND AND PURPOSE: Despite the frequent use of unenhanced head CT for the detection of acute neurologic deficit, the radiation dose for this exam varies widely. Our aim was to evaluate the performance of lower-dose head CT for detection of intracranial findings resulting in acute neurologic deficit. MATERIALS AND METHODS: Projection data from 83 patients undergoing unenhanced spiral head CT for suspected neurologic deficits were collected. Cases positive for infarction, intra-axial hemorrhage, mass, or extra-axial hemorrhage required confirmation by histopathology, surgery, progression of findings, or corresponding neurologic deficit; cases negative for these target diagnoses required negative assessments by two neuroradiologists and a clinical neurologist. A routine dose head CT was obtained using 250 effective mAs and iterative reconstruction. Lower-dose configurations were reconstructed (25-effective mAs iterative reconstruction, 50-effective mAs filtered back-projection and iterative reconstruction, 100-effective mAs filtered back-projection and iterative reconstruction, 200-effective mAs filtered back-projection). Three neuroradiologists circled findings, indicating diagnosis, confidence (0-100), and image quality. The difference between the jackknife alternative free-response receiver operating characteristic figure of merit at routine and lower-dose configurations was estimated. A lower 95% CI estimate of the difference greater than -0.10 indicated noninferiority. RESULTS: Forty-two of 83 patients had 70 intracranial findings (29 infarcts, 25 masses, 10 extra- and 6 intra-axial hemorrhages) at routine head CT (CT dose index = 38.3 mGy). The routine-dose jackknife alternative free-response receiver operating characteristic figure of merit was 0.87 (95% CI, 0.81-0.93). Noninferiority was shown for 100-effective mAs iterative reconstruction (figure of merit difference, -0.04; 95% CI, -0.08 to 0.004) and 200-effective mAs filtered back-projection (-0.02; 95% CI, -0.06 to 0.02) but not for 100-effective mAs filtered back-projection (-0.06; 95% CI, -0.10 to -0.02) or lower-dose levels. Image quality was better at higher-dose levels and with iterative reconstruction (P < .05). CONCLUSIONS: Observer performance for dose levels using 100-200 eff mAs was noninferior to that observed at 250 effective mAs with iterative reconstruction, with iterative reconstruction preserving noninferiority at a mean CT dose index of 15.2 mGy.


Assuntos
Encefalopatias/diagnóstico por imagem , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada Espiral/métodos , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Adulto Jovem
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