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1.
Clin Oncol (R Coll Radiol) ; 35(8): 524-532, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37357120

RESUMO

Radiation plays an important role in organ preservation for gastrointestinal malignancies, with a watch and wait strategy enabling surgery to be avoided in patients who are not suitable or who are refusing surgery. Brachytherapy boost allows the radiation dose to be escalated, which plays a pivotal role in the successful outcome of achieving organ preservation. Here we describe the role of brachytherapy in two common gastrointestinal malignancies (oesophagus and rectum). Their indications and how the brachytherapy procedures are carried out, together with the dose and fractionation commonly used are discussed. The use of brachytherapy needs to be included in the training curriculum at all academic centres so that its use is developed by the newer generation of radiation oncologists. Its current non-use due to bias, lack of training and availability is no longer justified, given the overwhelming published evidence for the role of brachytherapy to improve organ preservation for both radical treatment and palliation in gastrointestinal malignancies.


Assuntos
Braquiterapia , Neoplasias Gastrointestinais , Neoplasias Retais , Humanos , Neoplasias Retais/tratamento farmacológico , Reto , Terapia Neoadjuvante , Quimiorradioterapia , Braquiterapia/métodos , Neoplasias Gastrointestinais/radioterapia
2.
Clin Exp Immunol ; 198(1): 24-36, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30768780

RESUMO

Neutrophils are often exclusively considered as a first-line innate immune defence, able to rapidly kill or trap pathogens and causing in case of over-activation tissue damage. In the female reproductive tract, however, the presence and activity of neutrophils seems to be tightly regulated. Major players in orchestrating this regulation are cyclical steroid sex hormones present during the menstrual cycle and pregnancy. This review describes the role of sex hormones in regulating directly or indirectly the functionality of neutrophils, the role of neutrophils during fertilization and pregnancy and in controlling viral, fungal and bacterial infection. This review also discusses the consequence of overt neutrophil activation in pregnancy pathologies.


Assuntos
Citocinas/imunologia , Hormônios Esteroides Gonadais/imunologia , Ativação de Neutrófilo/imunologia , Neutrófilos/imunologia , Animais , Feminino , Humanos , Gravidez , Resultado da Gravidez
4.
BMJ Open ; 5(3): e007700, 2015 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-25795699

RESUMO

INTRODUCTION: Liver disease mortality and morbidity are rapidly rising and liver transplantation is limited by organ availability. Small scale human studies have shown that stem cell therapy is safe and feasible and has suggested clinical benefit. No published studies have yet examined the effect of stem cell therapy in a randomised controlled trial and evaluated the effect of repeated therapy. METHODS AND ANALYSIS: Patients with liver cirrhosis will be randomised to one of three trial groups: group 1: Control group, Standard conservative management; group 2 treatment: granulocyte colony-stimulating factor (G-CSF; lenograstim) 15 µg/kg body weight daily on days 1-5; group 3 treatment: G-CSF 15 µg/kg body weight daily on days 1-5 followed by leukapheresis, isolation and aliquoting of CD133+ cells. Patients will receive an infusion of freshly isolated CD133+ cells immediately and frozen doses at days 30 and 60 via peripheral vein (0.2×10(6) cells/kg for each of the three doses). Primary objective is to demonstrate an improvement in the severity of liver disease over 3 months using either G-CSF alone or G-CSF followed by repeated infusions of haematopoietic stem cells compared with standard conservative management. The trial is powered to answer two hypotheses of each treatment compared to control but not powered to detect smaller expected differences between the two treatment groups. As such, the overall α=0.05 for the trial is split equally between the two hypotheses. Conventionally, to detect a relevant standardised effect size of 0.8 point reduction in Model for End-stage Liver Disease score using two-sided α=0.05(overall α=0.1 split equally between the two hypotheses) and 80% power requires 27 participants to be randomised per group (81 participants in total). ETHICS AND DISSEMINATION: The trial is registered at Current Controlled Trials on 18 November 2009 (ISRCTN number 91288089, EuDRACT number 2009-010335-41). The findings of this trial will be disseminated to patients and through peer-reviewed publications and international presentations.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Terapia Baseada em Transplante de Células e Tecidos , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/métodos , Cirrose Hepática/terapia , Antígeno AC133 , Adolescente , Adulto , Idoso , Antígenos CD/análise , Medula Óssea , Glicoproteínas/análise , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/química , Humanos , Infusões Intravenosas , Lenograstim , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Pessoa de Meia-Idade , Peptídeos/análise , Proteínas Recombinantes/administração & dosagem , Projetos de Pesquisa , Transplante Autólogo , Adulto Jovem
5.
Placenta ; 35(11): 855-65, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25266889

RESUMO

INTRODUCTION: The dysregulation of maternal-fetal immune tolerance is one of the proposed mechanisms leading to preeclampsia. Galectins are key regulator proteins of the immune response in vertebrates and maternal-fetal immune tolerance in eutherian mammals. Previously we found that three genes in a Chr19 cluster encoding for human placental galectin-13 (PP13), galectin-14 and galectin-16 emerged during primate evolution and may confer immune tolerance to the semi-allogeneic fetus. MATERIALS AND METHODS: This study involved various methodologies for gene and protein expression profiling, genomic DNA methylation analyses, functional assays on differentiating trophoblasts including gene silencing, luciferase reporter and methylation assays. These methods were applied on placental specimens, umbilical cord blood cells, primary trophoblasts and BeWo cells. Genomic DNA sequences were analyzed for transposable elements, transcription factor binding sites and evolutionary conservation. RESULTS AND DISCUSSION: The villous trophoblastic expression of Chr19 cluster galectin genes is developmentally regulated by DNA methylation and induced by key transcription factors of villous placental development during trophoblast fusion and differentiation. This latter mechanism arose via the co-option of binding sites for these transcription factors through promoter evolution and the insertion of an anthropoid-specific L1PREC2 transposable element into the 5' untranslated region of an ancestral gene followed by gene duplication events. Among placental Chr19 cluster galectin genes, the expression of LGALS13 and LGALS14 is down-regulated in preterm severe preeclampsia associated with SGA. We reveal that this phenomenon is partly originated from the dysregulated expression of key transcription factors controlling trophoblastic functions and galectin gene expression. In addition, the differential DNA methylation of these genes was also observed in preterm preeclampsia irrespective of SGA. CONCLUSIONS: These findings reveal the evolutionary origins of the placental expression of Chr19 cluster galectins. The complex dysregulation of these genes in preeclampsia may alter immune tolerance mechanisms at the maternal-fetal interface.


Assuntos
Cromossomos Humanos Par 19 , Evolução Molecular , Galectinas/genética , Pré-Eclâmpsia/metabolismo , Trofoblastos/metabolismo , Regiões 5' não Traduzidas , Diferenciação Celular , Regulação para Baixo , Epigênese Genética , Feminino , Galectinas/metabolismo , Humanos , Família Multigênica , Gravidez , Fatores de Transcrição/metabolismo , Trofoblastos/citologia
6.
QJM ; 107(6): 417-21, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24453286

RESUMO

The liver has a unique capacity to repair following injury, which is largely achieved by proliferation of hepatocytes. However, in situations of chronic or overwhelming liver injury, additional repair mechanisms, namely liver progenitor or oval cells, are activated. These cells, located in the canals of Hering, express markers for both hepatocytes and biliary cells and have the capacity to differentiate down both hepatocyte and biliary lineages. Previous work has suggested that the administration of autologous or allogeneic cell therapies such as haematopoietic or mesenchymal stem cells can augment liver repair by either stimulating endogenous repair mechanisms or by suppressing ongoing damage. A better understanding of how cell therapies can promote liver regeneration will lead to the refinement of these therapeutic approaches and also develop new pharmacological agents for liver repair.


Assuntos
Hepatopatias/terapia , Regeneração Hepática/fisiologia , Transplante de Células-Tronco/métodos , Células-Tronco/fisiologia , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Transplante de Células-Tronco Mesenquimais/métodos
7.
Placenta ; 34(4): 360-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23453248

RESUMO

INTRODUCTION: We found isolated or clustered trophoblasts in the chorionic connective tissue of the extraplacental membranes, and defined this novel histologic feature as the "trophoblast islands of the chorionic connective tissue" (TICCT). This study was conducted to determine the clinical significance of TICCT. METHODS: Immunohistochemistry for cytokeratin-7 was performed on the chorioamniotic membranes (N = 2155) obtained from singleton pregnancies of 1199 uncomplicated term and 956 preterm deliveries. The study groups comprised 1236 African-American and 919 Hispanic women. Gestational age ranged from 24(+0) weeks to 41(+6) weeks. Multiple logistic regression analysis was performed to investigate the magnitude of association between patient characteristics and the presence of TICCT. RESULTS: The likelihood of TICCT was significantly associated with advancing gestational age both in term (OR: 1.29, 95% CI: 1.16-1.45, p < 0.001) and preterm deliveries (OR: 1.19, 95% CI: 1.07-1.32, p = 0.001) . Hispanic women were less likely than African-American women to have TICCT across gestation in term (OR: 0.23, 95% CI: 0.18-0.31, p < 0.001) and preterm pregnancies (OR: 0.41, 95% CI: 0.29-0.58, p < 0.001). Women with a female fetus were significantly more likely to have TICCT than women with a male fetus, in both term (OR: 1.64, 95% CI: 1.28-2.11, p < 0.001) and preterm gestations (OR: 2.04, 95% CI: 1.46-2.85, p < 0.001). TICCT was 40% less frequent in the presence of chronic placental inflammation [term (OR: 0.60, 95% CI: 0.45-0.81, p = 0.001) and preterm gestations (OR: 0.58, 95% CI: 0.40-0.84, p = 0.003)] and in parous women at term (OR: 0.60, 95% CI: 0.44-0.81, p = 0.001). CONCLUSIONS: Our findings suggest that the duration of pregnancy, fetal sex, and parity may influence the behavior of extravillous trophoblast and placental mesenchymal cells.


Assuntos
Córion/patologia , Doenças Placentárias/patologia , Trofoblastos/patologia , Negro ou Afro-Americano , Chile , Feminino , Hispânico ou Latino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Queratina-7/análise , Masculino , Michigan , Paridade , Placenta/patologia , Gravidez , Nascimento Prematuro/patologia , Fatores Sexuais , População Branca
8.
Placenta ; 34 Suppl: S6-10, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23253784

RESUMO

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2012 there were twelve themed workshops, four of which are summarized in this report. These workshops related to various aspects of placental biology: 1) epigenetics and imprinting in the placenta; 2) growth factors and villous trophoblast differentiation; 3) role of the placenta in regulating fetal exposure to xenobiotics during pregnancy; 4) infection and the placenta.


Assuntos
Epigênese Genética/fisiologia , Impressão Genômica/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Placenta/fisiologia , Complicações Infecciosas na Gravidez/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Trofoblastos/fisiologia , Xenobióticos/efeitos adversos , Diferenciação Celular/fisiologia , Feminino , Humanos , Placenta/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia
9.
Placenta ; 32 Suppl: S21-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20541258

RESUMO

BACKGROUND: The involvement of the placenta in the pathogenesis of preeclampsia and HELLP syndrome is well established, and placental lesions are also similar in these two syndromes. Here we aimed to examine the placental transcriptome and to identify candidate biomarkers in early-onset preeclampsia and HELLP syndrome. METHODS: Placental specimens were obtained at C-sections from women with early-onset preeclampsia and HELLP syndrome, and from controls who delivered preterm or at term. After histopathological examination, fresh-frozen placental specimens were used for microarray profiling and validation by qRT-PCR. Differential expression was analysed using log-linear models while adjusting for gestational age. Gene ontology and pathway analyses were used to interpret gene expression changes. Tissue microarrays were constructed from paraffin-embedded placental specimens and immunostained. RESULTS: Placental gene expression was gestational age-dependent among preterm and term controls. Out of the 350 differentially expressed genes in preeclampsia and 554 genes in HELLP syndrome, 224 genes (including LEP, CGB, LHB, INHA, SIGLEC6, PAPPA2, TREM1, and FLT1) changed in the same direction (elevated or reduced) in both syndromes. Many of these encode proteins that have been implicated as biomarkers for preeclampsia. Enrichment analyses revealed similar biological processes, cellular compartments and biological pathways enriched in early-onset preeclampsia and HELLP syndrome; however, some processes and pathways (e.g., cytokine-cytokine receptor interaction) were over-represented only in HELLP syndrome. CONCLUSION: High-throughput transcriptional and tissue microarray expression profiling revealed that placental transcriptomes of early-onset preeclampsia and HELLP syndrome largely overlap, underlying a potential common cause and pathophysiologic processes in these syndromes. However, gene expression changes may also suggest a more severe placental pathology and pronounced inflammatory response in HELLP syndrome than in preeclampsia.


Assuntos
Perfilação da Expressão Gênica , Síndrome HELLP/genética , Análise em Microsséries , Placenta/metabolismo , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/genética , Adulto , Estudos de Casos e Controles , Diagnóstico Precoce , Feminino , Expressão Gênica/fisiologia , Perfilação da Expressão Gênica/métodos , Idade Gestacional , Síndrome HELLP/diagnóstico , Síndrome HELLP/metabolismo , Síndrome HELLP/patologia , Humanos , Recém-Nascido , Análise em Microsséries/métodos , Placenta/química , Placenta/patologia , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/patologia , Gravidez
10.
Ultrasound Obstet Gynecol ; 35(2): 155-62, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20101637

RESUMO

OBJECTIVES: To examine the relationship between abnormalities in uterine (UtA) and/or umbilical artery (UA) Doppler velocimetry and maternal plasma concentrations of soluble endoglin (sEng) in patients with pre-eclampsia (PE). METHODS: A cross-sectional study was conducted in 135 normal pregnant women and 69 patients with PE. Patients with PE were subclassified into four groups: those who had Doppler abnormalities in both the UtA and UA, patients who had Doppler abnormalities in the UtA alone, those who had Doppler abnormalities in the UA alone, and patients without Doppler abnormalities in either vessel. Plasma concentrations of sEng were determined by enzyme-linked immunosorbent assay. RESULTS: Among patients with PE, those with abnormal UtA and UA Doppler velocimetry had the highest median plasma concentration of sEng compared with any other group (P < 0.001, Kruskal-Wallis test). Women with PE with normal Doppler velocimetry in both vessels had the lowest median plasma concentration of sEng. There was a significant relationship between plasma concentrations of sEng and mean UtA resistance index (Spearman Rho = 0.5, P < 0.001) as well as UA pulsatility index (Spearman Rho = 0.4, P = 0.002). Multiple regression analysis suggested that Doppler abnormalities in the UtA and UA as well as gestational age at blood sampling contributed to plasma sEng concentrations (P < 0.001). CONCLUSIONS: Abnormalities of impedance to blood flow in the UtA and UA are associated with an excess of sEng in the circulation of mothers with PE. These findings suggest that the 'antiangiogenic state' in PE is partially reflected in abnormalities of Doppler velocimetry.


Assuntos
Antígenos CD/sangue , Troca Materno-Fetal/fisiologia , Pré-Eclâmpsia/fisiopatologia , Receptores de Superfície Celular/sangue , Artérias Umbilicais/fisiopatologia , Artéria Uterina/fisiopatologia , Adolescente , Adulto , Biomarcadores/sangue , Velocidade do Fluxo Sanguíneo/fisiologia , Estudos Transversais , Endoglina , Feminino , Idade Gestacional , Humanos , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/diagnóstico por imagem , Gravidez , Fluxo Sanguíneo Regional/fisiologia , Estudos Retrospectivos , Ultrassonografia Pré-Natal , Artérias Umbilicais/diagnóstico por imagem , Artéria Uterina/diagnóstico por imagem , Adulto Jovem
11.
Growth Horm IGF Res ; 18(2): 174-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17910928

RESUMO

OBJECTIVE: Placental growth hormone (PGH) is produced by trophoblast. This hormone becomes detectable in maternal serum during the first trimester of pregnancy. Its concentration increases as term approaches and becomes undetectable within one hour of delivery. PGH has important biological properties, including somatogenic (growth promotion), lactogenic, and lipolytic activity. Recently, PGH has been detected in amniotic fluid (AF) of midtrimester pregnancies. The purpose of this study was to determine whether PGH concentrations in AF change with advancing gestational age and in labor at term. DESIGN: AF was assayed for PGH concentrations in samples obtained from patients undergoing genetic amniocentesis between 14 and 18 weeks of gestation (n=67), normal patients at term not in labor (n=24), and pregnant women at term in labor (n=51). PGH concentrations were determined by ELISA. Non-parametric statistics were used for analysis. RESULTS: (1) PGH was detected in all AF samples; (2) patients in the midtrimester had a higher median concentration of PGH in AF than those at term (midtrimester: median: 3140.5 pg/ml; range: 1124.2-13886.5 vs. term: median: 2021.1pg/ml; range: 181.6-8640.8; p<0.01); (3) there was no difference in the median concentration of PGH between women at term, not in labor, and those in labor (term not in labor: median: 2113.4pg/ml; range: 449.3-8640.8 vs. term in labor: median: 2004.1pg/ml; range: 181.6-8531.5; p=0.73). CONCLUSIONS: (1) PGH is detectable in AF at both mid- and third trimesters; (2) the median AF concentration of PGH is significantly lower at term when compared to the second trimester; (3) labor at term is not associated with changes in the AF concentration of PGH. The role of this unique placental hormone now found in the fetal compartment requires further investigation.


Assuntos
Líquido Amniótico/metabolismo , Idade Gestacional , Hormônio do Crescimento/metabolismo , Trabalho de Parto/fisiologia , Hormônios Placentários/metabolismo , Adulto , Amniocentese , Líquido Amniótico/química , Estudos Transversais , Feminino , Hormônio do Crescimento/análise , Hormônio do Crescimento/sangue , Humanos , Hormônios Placentários/análise , Hormônios Placentários/sangue , Gravidez , Complicações na Gravidez/sangue , Complicações na Gravidez/metabolismo , Segundo Trimestre da Gravidez/metabolismo , Terceiro Trimestre da Gravidez/metabolismo
12.
Placenta ; 29 Suppl A: S83-5, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18061661

RESUMO

Understanding the mechanisms of disease responsible for the syndrome of preeclampsia as well as early risk assessment is still a major challenge. The concentrations of circulating proteins in maternal blood such as placental growth factor, soluble vascular endothelial growth factor receptor-1 and soluble endoglin are altered weeks before the onset of clinical symptoms of the syndrome. Recently, other proteins in maternal serum, such as activin A, inhibin A, PAPP-A, and PP13 have been suggested to be of value in first trimester risk assessment. Since preeclampsia is a syndrome, it seems unlikely that a single test will predict all forms of preeclampsia. This realization has led to the formulation of a new conceptual framework suggesting that a combination of markers (biochemical and/or biophysical) may be required to conduct comprehensive risk assessment for the syndrome.


Assuntos
Biomarcadores , Marcadores Genéticos , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/epidemiologia , Educação , Feminino , Humanos , Pré-Eclâmpsia/genética , Valor Preditivo dos Testes , Gravidez , Fatores de Risco
13.
Ultrasound Obstet Gynecol ; 30(5): 706-14, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17712870

RESUMO

OBJECTIVES: To determine the clinical significance of the presence of amniotic fluid (AF) 'sludge' among asymptomatic patients at high risk for spontaneous preterm delivery. METHODS: This retrospective case-control study included 281 patients with (n = 66) or without (n = 215) AF 'sludge', who underwent transvaginal ultrasound examination between 13 and 29 completed weeks of gestation. Patients with threatened preterm labor, multiple gestation, fetal anomalies, placenta previa or uterine contractions were excluded. RESULTS: The prevalence of AF 'sludge' in the study population was 23.5% (66/281). The rates of spontaneous preterm delivery at < 28 weeks, < 32 weeks, < 35 weeks and < 37 weeks of gestation were 14.7% (29/197), 21.3% (46/216), 28.7% (62/216) and 42.1% (91/216), respectively. Patients with 'sludge' had: (1) a higher rate of spontaneous preterm delivery at < 28 weeks (46.5% (20/43) vs. 5.8% (9/154); P < 0.001), < 32 weeks (55.6% (25/45) vs. 12.3% (21/171); P < 0.001) and < 35 weeks (62.2% (28/45) vs. 19.9% (34/171); P < 0.001); (2) a higher frequency of clinical chorioamnionitis (15.2% (10/66) vs. 5.1% (11/215); P = 0.007), histologic chorioamnionitis (61.5% (40/65) vs. 28% (54/193); P < 0.001) and funisitis (32.3% (21/65) vs. 19.2% (37/193); P = 0.03); (3) a higher frequency of preterm prelabor rupture of membranes (PROM) (39.4% (26/66) vs. 13.5% (29/215); P < 0.001), lower gestational age at preterm PROM (median 24.7 (interquartile range (IQR), 22.3-28.1) weeks vs. 32.3 (IQR, 27.7-34.8) weeks; P < 0.001); and (4) shorter median ultrasound-to-delivery interval ('sludge' positive 127 days (95% CI, 120-134 days) vs. 'sludge' negative 161 days (95% CI, 153-169 days); P < 0.001) and ultrasound-to-preterm PROM interval ('sludge' positive 23 days (95% CI, 7-39 days) vs. 'sludge' negative 57 days (95% CI, 38-77 days); P = 0.003) than those without 'sludge'. AF 'sludge' was an independent explanatory variable for the occurrence of spontaneous preterm delivery at < 28 weeks, < 32 weeks and < 35 weeks, preterm PROM, microbial invasion of the amniotic cavity (MIAC) and histologic chorioamnionitis. Moreover, the combination of a cervical length < 25 mm and 'sludge' conferred an odds ratio of 14.8 and 9.9 for spontaneous preterm delivery at < 28 weeks and < 32 weeks, respectively. CONCLUSIONS: AF 'sludge' is an independent risk factor for spontaneous preterm delivery, preterm PROM, MIAC and histologic chorioamnionitis in asymptomatic patients at high risk for spontaneous preterm delivery. Furthermore, the combination of 'sludge' and a short cervix confers a higher risk for spontaneous preterm delivery at < 28 weeks and < 32 weeks than a short cervix alone.


Assuntos
Líquido Amniótico/diagnóstico por imagem , Trabalho de Parto Prematuro/etiologia , Complicações Infecciosas na Gravidez/diagnóstico por imagem , Adulto , Líquido Amniótico/microbiologia , Estudos de Casos e Controles , Colo do Útero/anormalidades , Feminino , Idade Gestacional , Humanos , Gravidez , Complicações Infecciosas na Gravidez/prevenção & controle , Estudos Retrospectivos , Fatores de Risco , Ultrassonografia
15.
BJOG ; 113 Suppl 3: 118-35, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17206980

RESUMO

High-dimensional biology (HDB) refers to the simultaneous study of the genetic variants (DNA variation), transcription (messenger RNA [mRNA]), peptides and proteins, and metabolites of an organ, tissue, or an organism in health and disease. The fundamental premise is that the evolutionary complexity of biological systems renders them difficult to comprehensively understand using only a reductionist approach. Such complexity can become tractable with the use of "omics" research. This term refers to the study of entities in aggregate. The current nomenclature of "omics" sciences includes genomics for DNA variants, transcriptomics for mRNA, proteomics for proteins, and metabolomics for intermediate products of metabolism. Another discipline relevant to medicine is pharmacogenomics. The two major advances that have made HDB possible are technological breakthroughs that allow simultaneous examination of thousands of genes, transcripts, and proteins, etc., with high-throughput techniques and analytical tools to extract information. What is conventionally considered hypothesis-driven research and discovery-driven research (through "omic" methodologies) are complementary and synergistic. Here we review data which have been derived from: 1) genomics to examine predisposing factors for preterm birth; 2) transcriptomics to determine changes in mRNA in reproductive tissues associated with preterm labour and preterm prelabour rupture of membranes; 3) proteomics to identify differentially expressed proteins in amniotic fluid of women with preterm labour; and 4) metabolomics to identify the metabolic footprints of women with preterm labour likely to deliver preterm and those who will deliver at term. The complementary nature of discovery science and HDB is emphasised.


Assuntos
Genômica/métodos , Trabalho de Parto Prematuro/etiologia , Diagnóstico Pré-Natal/métodos , Proteômica/métodos , Biomarcadores/análise , Feminino , Expressão Gênica , Predisposição Genética para Doença , Humanos , Trabalho de Parto Prematuro/genética , Trabalho de Parto Prematuro/metabolismo , Linhagem , Polimorfismo Genético , Gravidez , Transcrição Gênica
17.
Am J Kidney Dis ; 45(2): 372-80, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15685516

RESUMO

BACKGROUND: Previous comparisons of peritonitis rates between continuous ambulatory peritoneal dialysis (CAPD) and continuous cycling peritoneal dialysis (CCPD) have produced varying results. METHODS: Using United States Renal Data System data, the authors evaluated peritonitis rates in 1994 through 1997 incident CAPD (n = 9,190) and CCPD (n = 2,785) Medicare patients. Patients were characterized during a 6-month entry period (months 4 through 9) and followed for a maximum of 2 years (months 10 through 33). Medicare claims data provided the date of the first peritonitis episode during the follow-up period. The time to first peritonitis after 9 months of PD was compared by the log-rank test, and then by Cox regression with adjustment for peritoneal dialysis modality, age, sex, race, primary end-stage renal disease (ESRD) diagnosis, number of entry-period hospital days, peritonitis during the entry period, hematocrit value, and congestive heart failure. RESULTS: For CAPD and CCPD, the adjusted average months to first peritonitis after 9 months of PD were 17.1 and 16.1, respectively. The probabilities of remaining without a peritonitis episode after 1 year of follow-up were 0.53 and 0.50, respectively ( P = 0.008). The risk of peritonitis was lower for CAPD than for CCPD (relative risk, 0.939; 95% confidence interval, 0.883 to 0.998). Other significant risk factors included age or=36% had lower risk of peritonitis. CONCLUSION: Compared with CCPD, CAPD is associated with a slightly but significantly lower risk for development of a first peritonitis episode after 9 months of peritoneal dialysis therapy.


Assuntos
Bases de Dados Factuais , Diálise Peritoneal/efeitos adversos , Diálise Peritoneal/métodos , Peritonite/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Vigilância da População/métodos , Estados Unidos
18.
Placenta ; 26(1): 34-46, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15664409

RESUMO

Full-length cDNAs of placental protein 20 (PP20) were cloned by screening a human placental cDNA library, which encode a 243 amino acid protein, identical to human thiamin pyrophosphokinase (hTPK) as confirmed by protein sequence analysis. Genomic alignment showed that the PP20/hTPK gene contains 9 exons. It is abundantly expressed in placenta, as numerous EST clones were identified. As thiamine metabolism deficiencies have been seen in placental infarcts previously, these indicate that PP20/hTPK may have a role in placental diseases. Analysis of the 1kb promoter region showed numerous putative transcription factor binding sites, which might be responsible for the ubiquitous PP20/hTPK expression. This may also be in accordance with the presence of the protein in tissues responsible for the regulation of the exquisite balance between cell division, differentiation and survival. TPK activity of the purified and recombinant protein was proved by mass spectrometry with electrospray ionization. By Western blot, PP20/hTPK was found in all human normal and tumorous adult and fetal tissues in nearly equal amounts, but not in sera. By immunohistochemical and immunofluorescent confocal imaging methods, diffuse labelling in the cytoplasm of the syncytiotrophoblasts and weak staining of the trophoblasts were observed, and the amount of PP20/hTPK decreased from the first trimester to the end of gestation. A 3D model of PP20/hTPK was computed (PDB No.: 1OLY) by homology modelling. A high degree of structural homology showed that the thiamin binding site was highly similar to that of the mouse enzyme, but highly different from the bacterial ones. Comparison of the catalytic centre sequences revealed differences, raising the possibility of designing new drugs which specifically inhibit bacterial and fungal enzymes without affecting PP20/hTPK and offering the possibility for safe antimicrobial therapy during pregnancy.


Assuntos
Clonagem Molecular , Biblioteca Gênica , Proteínas da Gravidez/química , Tiamina Pirofosfoquinase/química , Adulto , Sequência de Aminoácidos , Animais , Sequência de Bases , Carcinoma/sangue , Carcinoma/química , Feminino , Idade Gestacional , Células HeLa , Humanos , Camundongos , Modelos Químicos , Dados de Sequência Molecular , Neoplasias/sangue , Neoplasias/química , Gravidez , Proteínas da Gravidez/genética , Análise de Sequência de Proteína , Tiamina Pirofosfoquinase/genética , Trofoblastos/química
19.
J Clin Pathol ; 58(1): 72-6, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15623487

RESUMO

An extremely high alkaline phosphatase (AP) concentration (3609 IU/litre) was found in a 20 year old primigravida at 37 week's gestation, prompting an examination of its histological and cellular origin. Immunohistochemistry and western blots using antibodies against AP, Ki-67, phospho-protein kinase B (Akt), phospho-p44/42 mitogen activated protein kinase/extracellular signal regulated kinase 1/2 (MAPK/Erk1/2), phospho-glycogen synthase kinase-3beta (GSK-3beta), phospho-stress activated protein kinase/c-Jun N-terminal kinase, total-Akt, total-GSK-3beta, and phospho-p38-MAPK were carried out on index and control placental samples of the same gestational age. Compared with controls, staining of the index placenta showed minimal AP labelling of the brush border and remarkable positivity of the intervillous space. Cytotrophoblastic proliferation was 8-10% in the index placenta compared with 1-2% in controls. The index placenta also had raised concentrations of protein kinases with important roles in cell differentiation. The proliferation and differentiation rates of the cytotrophoblasts were found to be five times higher in index samples than in controls. It is hypothesised that loss of syncytial membranes in immature villi led to increased AP concentrations in the maternal circulation and decreased AP staining of the placenta. Loss of the syncytium might also stimulate increased proliferation of villous cytotrophoblasts, which would then fuse and maintain the syncytium.


Assuntos
Fosfatase Alcalina/sangue , Gravidez/sangue , Trofoblastos/enzimologia , Adulto , Western Blotting , Diferenciação Celular , Divisão Celular , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Placenta/enzimologia , Trofoblastos/citologia
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