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1.
BJOG ; 129(4): 619-626, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34529344

RESUMO

OBJECTIVE: To evaluate the association between maternal fructosamine levels at the time of delivery and stillbirth. DESIGN: Secondary analysis of a case-control study. SETTING: Multicentre study of five geographic catchment areas in the USA. POPULATION: All singleton stillbirths with known diabetes status and fructosamine measurement, and representative live birth controls. MAIN OUTCOME MEASURES: Fructosamine levels in stillbirths and live births among groups were adjusted for potential confounding factors, including diabetes. Optimal thresholds of fructosamine to discriminate stillbirth and live birth. RESULTS: A total of 529 women with a stillbirth and 1499 women with a live birth were included in the analysis. Mean fructosamine levels were significantly higher in women with a stillbirth than in women with a live birth after adjustment (177 ± 3.05 versus 165 ± 2.89 µmol/L, P < 0.001). The difference in fructosamine levels between stillbirths and live births was greater among women with diabetes (194 ± 8.54 versus 162 ± 3.21 µmol/L), compared with women without diabetes (171 ± 2.50 versus 162 ± 2.56 µmol/L). The area under the curve (AUC) for fructosamine level and stillbirth was 0.634 (0.605-0.663) overall, 0.713 (0.624-0.802) with diabetes and 0.625 (0.595-0.656) with no diabetes. CONCLUSIONS: Maternal fructosamine levels at the time of delivery were higher in women with stillbirth compared with women with live birth. Differences were substantial in women with diabetes, suggesting a potential benefit of glycaemic control in women with diabetes during pregnancy. The small differences noted in women without diabetes are not likely to justify routine screening in all cases of stillbirth. TWEETABLE ABSTRACT: Maternal serum fructosamine levels are higher in women with stillbirth than in women with live birth, especially in women with diabetes.


Assuntos
Frutosamina/sangue , Natimorto/epidemiologia , Adulto , Estudos de Casos e Controles , Causalidade , Feminino , Humanos , Nascido Vivo/epidemiologia , Gravidez , Curva ROC , Fatores de Risco , Estados Unidos/epidemiologia
2.
BJOG ; 128(2): 252-258, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32946651

RESUMO

OBJECTIVE: Approximately 10% of stillbirths are attributed to fetal anomalies, but anomalies are also common in live births. We aimed to assess the relationship between anomalies, by system and stillbirth. DESIGN: Secondary analysis of a prospective, case-control study. SETTING: Multicentre, 59 hospitals in five regional catchment areas in the USA. POPULATION OR SAMPLE: All stillbirths and representative live birth controls. METHODS: Standardised postmortem examinations performed in stillbirths, medical record abstraction for stillbirths and live births. MAIN OUTCOME MEASURES: Incidence of major anomalies, by type, compared between stillbirths and live births with univariable and multivariable analyses using weighted analysis to account for study design and differential consent. RESULTS: Of 465 singleton stillbirths included, 23.4% had one or more major anomalies compared with 4.3% of 1871 live births. Having an anomaly increased the odds of stillbirth; an increasing number of anomalies was more highly associated with stillbirth. Regardless of organ system affected, the presence of an anomaly increased the odds of stillbirth. These relationships remained significant if stillbirths with known genetic abnormalities were excluded. After multivariable analyses, the adjusted odds ratio (aOR) of stillbirth for any anomaly was 4.33 (95% CI 2.80-6.70) and the systems most strongly associated with stillbirth were cystic hygroma (aOR 29.97, 95% CI 5.85-153.57), and thoracic (aOR16.18, 95% CI 4.30-60.94) and craniofacial (aOR 35.25, 95% CI 9.22-134.68) systems. CONCLUSIONS: In pregnancies affected by anomalies, the odds of stillbirth are higher with increasing numbers of anomalies. Anomalies of nearly any organ system increased the odds of stillbirth even when adjusting for gestational age and maternal race. TWEETABLE ABSTRACT: Stillbirth risk increases with anomalies of nearly any organ system and with number of anomalies seen.


Assuntos
Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/patologia , Doenças Fetais/epidemiologia , Doenças Fetais/patologia , Natimorto/epidemiologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Incidência , Nascido Vivo , Razão de Chances , Gravidez , Estudos Prospectivos , Fatores de Risco
3.
J Perinatol ; 39(2): 193-202, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30353080

RESUMO

OBJECTIVE: To compare neurodevelopmental outcomes in linear growth-restricted (LGR) infants born <29 weeks with and without weight gain out of proportion to linear growth. STUDY DESIGN: We compared 2-year neurodevelopmental outcomes between infants with and without LGR and between LGR infants with and without weight gain out of proportion to linear growth. The outcomes were Bayley-III cognitive, motor, and language scores, cerebral palsy, Gross Motor Function Classification System (GMFCS) level ≥ 2, and neurodevelopmental impairment. RESULT: In total, 1227 infants were analyzed. LGR infants were smaller and less mature at birth, had higher BMI, and had lower Bayley-III language scores (82.3 vs. 85.0, p < 0.05). Among infants with LGR, infants with high BMI had lower language scores compared with those with low-to-normal BMI (80.8 vs. 83.3, p < 0.05), and were more likely to have GMFCS level ≥2 and neurodevelopmental impairment. CONCLUSION: Among infants with LGR, weight gain out of proportion to linear growth was associated with poorer neurodevelopmental outcomes.


Assuntos
Lactente Extremamente Prematuro/crescimento & desenvolvimento , Testes Neuropsicológicos , Aumento de Peso , Paralisia Cerebral/diagnóstico , Transtornos Cognitivos/diagnóstico , Bases de Dados Factuais , Deficiências do Desenvolvimento/diagnóstico , Feminino , Humanos , Lactente , Recém-Nascido , Transtornos do Desenvolvimento da Linguagem/diagnóstico , Masculino , Transtornos Motores/diagnóstico , National Institute of Child Health and Human Development (U.S.) , Estudos Retrospectivos , Estados Unidos
4.
J Perinatol ; 37(11): 1220-1223, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28880260

RESUMO

OBJECTIVE: To analyze reasons for low enrollment in a randomized controlled trial (RCT) of the effect of hydrocortisone for cardiovascular insufficiency on survival without neurodevelopmental impairment (NDI) in term/late preterm newborns. STUDY DESIGN: The original study was a multicenter RCT. Eligibility: ⩾34 weeks' gestation, <72 h old, mechanically ventilated, receiving inotrope. Primary outcome was NDI at 2 years; infants with diagnoses at high risk for NDI were excluded. This paper presents an analysis of reasons for low patient enrollment. RESULTS: Two hundred and fifty-seven of the 932 otherwise eligible infants received inotropes; however, 207 (81%) had exclusionary diagnoses. Only 12 infants were randomized over 10 months; therefore, the study was terminated. Contributing factors included few eligible infants after exclusions, open-label steroid therapy and a narrow enrollment window. CONCLUSION: Despite an observational study to estimate the population, very few infants were enrolled. Successful RCTs of emergent therapy may require fewer exclusions, a short-term primary outcome, waiver of consent and/or other alternatives.


Assuntos
Cardiotônicos/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Hidrocortisona/uso terapêutico , Seleção de Pacientes , Estado Terminal/terapia , Método Duplo-Cego , Término Precoce de Ensaios Clínicos , Cardiopatias Congênitas/tratamento farmacológico , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Consentimento Livre e Esclarecido , Transtornos do Neurodesenvolvimento/prevenção & controle
6.
J Perinatol ; 36(12): 1116-1121, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27629374

RESUMO

OBJECTIVE: To compare neurodevelopmental outcomes in postnatal growth-restricted infants born <29 weeks with and without postnatal head-sparing (PHS). STUDY DESIGN: We analyzed developmental outcomes at 2 years of age among postnatally growth-restricted infants with and without head-sparing. The primary outcome was Bayley III cognitive composite score; secondary outcomes included Bayley III motor composite score, moderate/severe cerebral palsy, gross motor functional classification scale level⩾2, and presence or absence of neurodevelopmental impairment (NDI). RESULTS: Of 1098 infants evaluated at 18 to 22 months, 658 were postnatally growth restricted, of whom 301 had head-sparing. In the multivariate model including independent risk factors for poor growth and poor developmental outcome, infants with head-sparing had higher adjusted motor composite scores (mean difference 4.65, P<0.01), but no differences in other neurodevelopmental outcomes. CONCLUSION: PHS is associated with improved neurodevelopmental outcome in extremely preterm infants, specifically Bayley III motor scores, but whether beneficial effects of PHS persist later in life is unknown.


Assuntos
Desenvolvimento Infantil , Deficiências do Desenvolvimento/diagnóstico , Lactente Extremamente Prematuro/crescimento & desenvolvimento , Estudos de Casos e Controles , Pré-Escolar , Feminino , Retardo do Crescimento Fetal/terapia , Humanos , Lactente , Recém-Nascido de Baixo Peso , Deficiência Intelectual/diagnóstico , Masculino , Destreza Motora , Estudos Prospectivos
7.
HIV Med ; 17(3): 206-15, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26354678

RESUMO

BACKGROUND: Since September 2014, zidovudine (ZDV)-based therapy for HIV has been the preferred second-line WHO regimen in Cameroon, but its use is limited by the risk of anaemia at standard dosage. We assessed the safety of a reduced vs. standard dose of ZDV to decrease the risk of anaemia in treatment-naïve, HIV-infected individuals. METHODS: In a prospective, randomized, open-label trial in an HIV clinic in Cameroon, 142 eligible adults (CD4 count < 350 cells/µL) were randomized to receive 24 weeks of a regimen comprising lamivudine plus nevirapine with either a reduced (400 mg) or standard dose (600 mg) of ZDV. The primary endpoint was the proportion of participants with new/worsening anaemia. RESULTS: Median age was 35 years; 58.5% were women; median body mass index was 23.2 kg/m(2) . At baseline, median haemoglobin was 11.6 g/dL, median CD4 cell count was 163 cells/µL, and median plasma HIV-1 RNA load was 5.4 log10 copies/mL. The proportion of participants with new/worsening anaemia was 37.5% (400 mg ZDV) and 32.9% (600 mg ZDV) (P = 0.563). Ten patients with severe anaemia required a switch from ZDV to tenofovir (11.4% in standard-dose arm vs. 2.8% in low-dose arm; P = 0.054). At 24 weeks, there was no significant difference between treatment groups, including median CD4 T-cell count increases. CONCLUSIONS: No significant difference was observed in the overall rate of anaemia between HIV-infected individuals starting a ZDV-based treatment according to a standard- or reduced-dose regimen. Severe anaemia and treatment switches related to study drug, however, were more frequent with 600 mg than 400 mg ZDV.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/efeitos adversos , Infecções por HIV/tratamento farmacológico , Zidovudina/administração & dosagem , Zidovudina/efeitos adversos , Adulto , Anemia/induzido quimicamente , Anemia/epidemiologia , Camarões , Relação Dose-Resposta a Droga , Quimioterapia Combinada/métodos , Feminino , Humanos , Lamivudina/administração & dosagem , Lamivudina/uso terapêutico , Masculino , Nevirapina/administração & dosagem , Nevirapina/uso terapêutico , Estudos Prospectivos , Resultado do Tratamento
8.
J Perinatol ; 34(11): 842-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24901452

RESUMO

OBJECTIVE: The use of inhaled nitric oxide (iNO) in preterm infants remains controversial. In October 2010, a National Institutes of Health consensus development conference cautioned against use of iNO in preterm infants. This study aims (1) to determine the prevalence and variability in use of iNO in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NICHD NRN) before and after the consensus conference and (2) separately, to examine associations between iNO use and severe bronchopulmonary dysplasia (BPD) or death. STUDY DESIGN: The NICHD NRN Generic Database collects data including iNO use on very preterm infants. A total of 13 centers contributed data across the time period 2008 to 2011. Infants exposed or not to iNO were compared using logistic regression, which included factors related to risk as well as their likelihood of being exposed to iNO. RESULT: A total of 4885 infants were assessed between 2008 and 2011; 128 (2.6%) received iNO before day 7, 140 (2.9%) between day 7 and 28, and 47 (1.0%) at >28 days. Center-specific iNO use during 2008 to 2010 ranged from 21.9 to 0.4%; 12 of 13 sites reduced usage and overall NRN iNO usage decreased from 4.6 to 1.6% (P<0.001) in 2011. The use of iNO started between day 7 and day 14 was more prevalent among younger infants with more severe courses in week 1 and associated with increased risk of severe BPD or death (odds ratio 2.24; 95% confidence interval 1.23 to 4.07). CONCLUSION: The variability and total use of iNO decreased in 2011 compared with 2008 to 2010. iNO administration started at ⩾ day 7 was associated with more severe outcomes compared with infants without iNO exposure.


Assuntos
Displasia Broncopulmonar/terapia , Óxido Nítrico/administração & dosagem , Administração por Inalação , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Modelos Logísticos , Masculino , Pontuação de Propensão
9.
J Perinatol ; 34(4): 301-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24503912

RESUMO

OBJECTIVE: To examine changes in arterial blood pressure (ABP) after birth in extremely preterm infants. STUDY DESIGN: Prospective observational study of infants 23(0/7) to 26(6/7) weeks gestational age (GA). Antihypotensive therapy use and ABP measurements were recorded for the first 24 h. RESULT: A cohort of 367 infants had 18 709 ABP measurements recorded. ABP decreased for the first 3 h, reached a nadir at 4 to 5 h and then increased at an average rate of 0.2 mm Hg h(-1). The rise in ABP from hour 4 to 24 was similar for untreated infants (n=164) and infants given any antihypotensive therapy (n=203), a fluid bolus (n=135) or dopamine (n=92). GA-specific trends were similar. ABP tended to be lower as GA decreased, but varied widely at each GA. CONCLUSION: ABP increased spontaneously over the first 24 postnatal hours for extremely preterm infants. The rate of rise in ABP did not change with antihypotensive therapy.


Assuntos
Pressão Arterial/fisiologia , Lactente Extremamente Prematuro/fisiologia , Pressão Arterial/efeitos dos fármacos , Feminino , Humanos , Hipotensão/tratamento farmacológico , Recém-Nascido , Masculino , Estudos Prospectivos
10.
J Perinatol ; 34(3): 203-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24370654

RESUMO

OBJECTIVE: Severe intracranial hemorrhage (ICH) is an important prognostic variable in extremely preterm (EPT) infants. We examined imaging and clinical variables that predict outcomes in EPT infants with severe ICH. STUDY DESIGN: Retrospective analysis of 353 EPT infants with severe ICH. Outcomes were compared by examining: (i) unilateral vs bilateral ICH; and (ii) presence vs absence of hemorrhagic parenchymal infarction (HPI). Regression analyses identified variables associated with death or neurodevelopmental impairment (NDI). RESULT: Bilateral ICH and HPI had higher rates of adverse outcomes and were independently associated with death/NDI. HPI was the most important variable for infants of lower birth weight, and bilateral ICH for larger infants. For infants surviving to 36 weeks, shunt placement was most associated with death/NDI. CONCLUSION: Bilateral ICH and the presence of HPI in EPT infants with severe ICH are associated with death/NDI, though the importance depends on birth weight and survival to 36 weeks.


Assuntos
Infarto Cerebral/complicações , Lactente Extremamente Prematuro , Doenças do Prematuro/mortalidade , Hemorragias Intracranianas/complicações , Infarto Cerebral/mortalidade , Paralisia Cerebral/etiologia , Humanos , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Recém-Nascido , Deficiência Intelectual/etiologia , Hemorragias Intracranianas/mortalidade , Hemorragias Intracranianas/patologia , Modelos Logísticos , Estudos Retrospectivos
11.
J Perinatol ; 34(1): 64-70, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24135709

RESUMO

OBJECTIVE: To determine if extremely low birth weight infants with surgical necrotizing enterocolitis have a higher risk of death or neurodevelopmental impairment and neurodevelopmental impairment among survivors (secondary outcome) at 18-22 months corrected age compared with infants with spontaneous intestinal perforation and infants without necrotizing enterocolitis or spontaneous intestinal perforation. STUDY DESIGN: Retrospective analysis of the Neonatal Research Network very low birth weight registry, evaluating extremely low birth weight infants born between 2000 and 2005. The study infants were designated into three groups: (1) spontaneous intestinal perforation without necrotizing enterocolitis; (2) surgical necrotizing enterocolitis (Bell's stage III); and (3) neither spontaneous intestinal perforation nor necrotizing enterocolitis. Multivariate logistic regression analysis was performed to evaluate the association between the clinical group and death or neurodevelopmental impairment, controlling for multiple confounding factors including center. RESULT: Infants with surgical necrotizing enterocolitis had the highest rate of death before hospital discharge (53.5%) and death or neurodevelopmental impairment (82.3%) compared with infants in the spontaneous intestinal perforation group (39.1 and 79.3%) and no necrotizing enterocolitis/no spontaneous intestinal perforation group (22.1 and 53.3%; P<0.001). Similar results were observed for neurodevelopmental impairment among survivors. On logistic regression analysis, both spontaneous intestinal perforation and surgical necrotizing enterocolitis were associated with increased risk of death or neurodevelopmental impairment (adjusted odds ratio 2.21, 95% confidence interval (CI): 1.5, 3.2 and adjusted OR 2.11, 95% CI: 1.5, 2.9, respectively) and neurodevelopmental impairment among survivors (adjusted OR 2.17, 95% CI: 1.4, 3.2 and adjusted OR 1.70, 95% CI: 1.2, 2.4, respectively). CONCLUSION: Spontaneous intestinal perforation and surgical necrotizing enterocolitis are associated with a similar increase in the risk of death or neurodevelopmental impairment and neurodevelopmental impairment among extremely low birth weight survivors at 18-22 months corrected age.


Assuntos
Deficiências do Desenvolvimento/etiologia , Enterocolite Necrosante/complicações , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Perfuração Intestinal/complicações , Desenvolvimento Infantil , Enterocolite Necrosante/cirurgia , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Gravidez , Estudos Retrospectivos , Fatores Socioeconômicos , Esteroides/uso terapêutico , Adulto Jovem
12.
J Anim Sci ; 91(10): 4713-29, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23942716

RESUMO

At birth, the newborn mammal undergoes a transition from a sterile uterine environment with a constant nutrient supply, to a microbe-rich environment with intermittent oral intake of complex milk nutrients via the gastrointestinal tract (GIT). These functional challenges partly explain the relatively high morbidity and mortality of neonates. Preterm birth interrupts prenatal organ maturation, including that of the GIT, and increases disease risk. Exemplary is necrotizing enterocolitis (NEC), which is associated closely with GIT immaturity, enteral feeding, and bacterial colonization. Infants with NEC may require resection of the necrotic parts of the intestine, leading to short bowel syndrome (SBS), characterized by reduced digestive capacity, fluid loss, and dependency on parenteral nutrition. This review presents the preterm pig as a translational model in pediatric gastroenterology that has provided new insights into important pediatric diseases such as NEC and SBS. We describe protocols for delivery, care, and handling of preterm pigs, and show how the immature GIT responds to delivery method and different nutritional and therapeutic interventions. The preterm pig may also provide a sensitive model for postnatal adaptation of weak term piglets showing high mortality. Attributes of the preterm pig model include close similarities with preterm infants in body size, organ development, and many clinical features, thereby providing a translational advantage relative to rodent models of GIT immaturity. On the other hand, the need for a sow surgical facility, a piglet intensive care unit, and clinically trained personnel may limit widespread use of preterm pigs. Studies on organ adaptation in preterm pigs help to identify the physiological basis of neonatal survival for hypersensitive newborns and aid in defining the optimal diet and rearing conditions during the critical neonatal period.


Assuntos
Animais Recém-Nascidos , Trato Gastrointestinal/crescimento & desenvolvimento , Recém-Nascido Prematuro/fisiologia , Nascimento Prematuro , Suínos/fisiologia , Animais , Feminino , Trato Gastrointestinal/fisiologia , Humanos , Gravidez
13.
J Anim Sci ; 91(5): 1991-2000, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23729782

RESUMO

Bile acids have historically been considered to mainly function in cholesterol homeostasis and facilitate fat digestion in the gastrointestinal tract. Recent discoveries show that bile acids also function as signaling molecules that exert diverse endocrine and metabolic actions by activating G protein-coupled bile acid receptor 1 (GPBAR1/G-protein-coupled bile acid receptor 1 or TGR5), a membrane G protein-coupled receptor, and farnesoid X receptor (FXR), a member of the nuclear hormone receptor superfamily. These bile acid sensing receptors are expressed in intestinal epithelial cells, TGR5 in enteroendocrine cells and FXR in enterocytes, which line the mucosa of gut lumen. A dominant effect of intestinal FXR activation by bile acids is secretion of fibroblast growth factor (FGF) 19, a novel enterokine that functions as a central enterohepatic signal to maintain bile acid homeostasis in the liver. Activation of TGR5 on enteroendocrine cells stimulates secretion of glucagon-like peptides (GLP)-1 and -2, which function, respectively, as the major incretin hormone involved in glucose homeostasis and key trophic hormone in intestinal adaptation and growth in response to food ingestion. The biological actions induced by bile acid activation of intestinal FXR and TGR5 have important therapeutic implications for the pathogenesis and treatment of several metabolic diseases, such as cholestasis and diabetes. This review highlights these new developments in the biology of intestinal bile acid sensing and metabolic function and discusses the potential implications for the health and agricultural production of domestic swine.


Assuntos
Ácidos e Sais Biliares/metabolismo , Homeostase , Intestinos/fisiologia , Transdução de Sinais , Suínos/fisiologia , Animais , Células Epiteliais/fisiologia , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Peptídeo 2 Semelhante ao Glucagon/metabolismo , Humanos , Camundongos/fisiologia , Ratos/fisiologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
14.
J Perinatol ; 33(8): 613-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23370608

RESUMO

OBJECTIVE: Sepsis in older children and adults modifies immune system function. We compared serotype-specific antibody responses to heptavalent pneumococcal conjugate vaccine (PCV7) in very low birth weight infants (<1500 g,VLBWs) with and without blood stream infection (BSI) during their birth hospitalization. STUDY DESIGN: Retrospective analysis of prospectively collected data for the Neonatal Research Network study of PCV7 responses among VLBWs. Infants received PCV7 at 2, 4 and 6 months after birth with blood drawn 4 to 6 weeks after third dose. Serotype antibodies were compared between infants with or without a history of BSI. Regression models were constructed with BW groups and other confounding factors identified in the primary study. RESULT: In all, 244 infants completed the vaccine series and had serum antibody available; 82 had BSI. After adjustment, BSI was not associated with reduced odds of serum antibody 0.35 µg ml(-1). CONCLUSION: BSI was not associated with reduced odds of World Health Organization-defined protective PCV7 responses in VLBWs.


Assuntos
Doenças do Prematuro/imunologia , Recém-Nascido de muito Baixo Peso/imunologia , Vacinas Pneumocócicas/imunologia , Sepse/imunologia , Feminino , Vacina Pneumocócica Conjugada Heptavalente , Humanos , Recém-Nascido , Masculino , Estudos Retrospectivos
15.
J Anim Sci ; 89(12): 4093-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21821812

RESUMO

Cysteine is a semi-indispensable AA in neonates and is synthesized from the indispensable AA, methionine, by transsulfuration. We previously showed that the gastrointestinal tract (GIT) is a metabolically important site of methionine transsulfuration to cysteine, yet the metabolic fate of dietary cysteine in the GIT has not been established. Cysteine use by gut epithelial cells may play an important role for maintenance of glutathione synthesis and cellular redox function. Our aim was to quantify the extent of gastrointestinal first-pass cysteine metabolism in young pigs. Four-week-old weanling pigs (n = 10) were fed a liquid milk-replacer diet and given an intragastric and intravenous [1-(13)C]cysteine infusion on 2 separate days in a crossover design. Arterial and portal blood samples were collected for cysteine isotopic enrichment by gas chromatography-mass spectrometry and for (13)CO(2) enrichment by isotope ratio mass spectrometry. Our results indicated that dietary cysteine is metabolized during its first-pass splanchnic metabolism, accounting for about 40% of dietary cysteine intake. We also showed that intestinal absorption was the major metabolic fate of dietary cysteine, representing about 75% of intake, indicating that the GIT utilizes 25% of the dietary cysteine intake. Thus, utilization by the GIT represents about one-half (approximately 53%) of the first-pass, splanchnic uptake of dietary cysteine. Moreover, a substantial proportion of dietary splanchnic cysteine metabolism was consumed by the GIT via nonoxidative pathways. We conclude that the gut utilizes 25% of the dietary cysteine intake and that synthesis of mucosal epithelial proteins, such as glutathione and mucin, are a major nonoxidative metabolic fate for cysteine.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Cisteína/farmacocinética , Proteínas Alimentares , Circulação Esplâncnica/fisiologia , Suínos/metabolismo , Ração Animal/análise , Animais , Estudos Cross-Over , Cisteína/administração & dosagem , Cisteína/metabolismo , Dieta/veterinária , Nutrição Enteral , Feminino , Injeções Intravenosas , Substitutos do Leite , Desmame
16.
Rev Sci Instrum ; 80(7): 074501, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19655969

RESUMO

We discuss the design, operation, and performance of a vacuum setup constructed for use in zero (or reduced) gravity conditions to initiate collisions of fragile millimeter-sized particles at low velocity and temperature. Such particles are typically found in many astronomical settings and in regions of planet formation. The instrument has participated in four parabolic flight campaigns to date, operating for a total of 2.4 h in reduced-gravity conditions and successfully recording over 300 separate collisions of loosely packed dust aggregates and ice samples. The imparted particle velocities achieved range from 0.03 to 0.28 m s(-1) and a high-speed, high-resolution camera captures the events at 107 frames/s from two viewing angles separated by either 48.8 degrees or 60.0 degrees. The particles can be stored inside the experiment vacuum chamber at temperatures of 80-300 K for several uninterrupted hours using a built-in thermal accumulation system. The copper structure allows cooling down to cryogenic temperatures before commencement of the experiments. Throughout the parabolic flight campaigns, add-ons and modifications have been made, illustrating the instrument flexibility in the study of small particle collisions.


Assuntos
Temperatura Baixa , Aceleradores de Partículas/instrumentação , Ausência de Peso , Desenho Assistido por Computador , Cobre , Poeira , Desenho de Equipamento , Gelo , Movimento (Física) , Vácuo
17.
J Perinatol ; 29(1): 57-62, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18716628

RESUMO

OBJECTIVE: To determine the association between human milk (HM) intake and risk of necrotizing enterocolitis (NEC) or death among infants 401 to 1000 g birth weight. STUDY DESIGN: Analysis of 1272 infants in the National Institute of Child Health and Human Development Neonatal Network Glutamine Trial was performed to determine if increasing HM intake was associated with decreased risk of NEC or death. HM intake was defined as the proportion of HM to total intake, to enteral intake and total volume over the first 14 days. Known NEC risk factors were included as covariates in Cox proportional hazard analyses for duration of survival time free of NEC. RESULT: Among study infants, 13.6% died or developed NEC after 14 days. The likelihood of NEC or death after 14 days was decreased by a factor of 0.83 (95% confidence interval, CI 0.72, 0.96) for each 10% increase in the proportion of total intake as HM. Each 100 ml kg(-1) increase in HM intake during the first 14 days was associated with decreased risk of NEC or death (hazard ratio, HR 0.87 (95% CI 0.77, 0.97)). There appeared to be a trend towards a decreased risk of NEC or death among infants who received 100% HM as a proportion to total enteral intake (HM plus formula), although this finding was not statistically significant (HR 0.85 (95% CI 0.60, 1.19)). CONCLUSION: These data suggest a dose-related association of HM feeding with a reduction of risk of NEC or death after the first 2 weeks of life among extremely low birth weight infants.


Assuntos
Enterocolite Necrosante/prevenção & controle , Mortalidade Infantil , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Leite Humano , Nutrição Enteral , Feminino , Humanos , Recém-Nascido , Masculino , Fatores de Risco
18.
J Perinatol ; 27(6): 359-64, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17443198

RESUMO

OBJECTIVE: To examine the association between weight loss during the first 10 days of life and the incidence of death or bronchopulmonary dysplasia (BPD) in small for gestational age (SGA) and appropriate for gestational age (AGA) extremely low-birth-weight infants. DESIGN/METHODS: This is a retrospective analysis of a cohort of ELBW (birth weight <1000 g) infants from the NICHD Neonatal Research Network's database. The cohort consisted of 9461 ELBW infants with gestational age of 24-29 weeks, admitted to Network's participating centers during calendar years 1994-2002 and surviving at least 72 h after birth. The cohort was divided into two groups, 1248 SGA (with birth weight below 10th percentile for gestational age) and 8213 AGA (with birth weight between 10th and 90th percentile) infants. We identified infants with or without weight loss during the first 10 days of life, which we termed as 'early postnatal weight loss' (EPWL). Univariate analyses were used to predict whether EPWL was related to the primary outcome, death or BPD, within each birth weight/gestation category (SGA or AGA). BPD and death were also analyzed separately in relation to EPWL. Logistic regression analysis was done to evaluate the risk of death or BPD in SGA and AGA groups, controlling for maternal and neonatal demographic and clinical factors found to be significant by univariate analysis. RESULTS: SGA ELBW infants had a lower prevalence of EPWL as compared with AGA ELBW infants (81.2 vs 93.7%, respectively, P<0.001). In AGA infants, univariate analysis showed that death or BPD rate was lower in the group of infants with EPWL compared with infants without EPWL (53.4 vs 74.3%, respectively, P<0.001). The BPD (47.2 vs 64%, P<0.001) and death (13.8 vs 32.9%, P<0.001) rate were similarly lower in the EPWL group. The risk-adjusted odds ratios (ORs) showed that EPWL was associated with lower rate of death or BPD (OR 0.47, 95% CI: 0.37-0.60). In SGA infants, on univariate analysis, a similar association between EPWL and outcomes was seen as shown in AGA infants: death or BPD (55.9 vs 75.2%, P<0.001), BPD rate (48.3 vs 62.1%, P=0.002) and rate death (19 vs 40.8%, P<0.001) for those with or without EPWL, respectively. Multiple logistic regression showed that as in AGA ELBW infants, EPWL was associated with lower risk for death or BPD (OR 0.60, 95% CI: 0.41-0.89) among SGA infants. CONCLUSIONS: SGA infants experienced less EPWL when compared with their AGA counterparts. EPWL was associated with a lower risk of death or BPD in both ELBW AGA and SGA infants. These data suggest that clinicians who consider the association between EPWL and risk of death or BPD should do so independent of gestation/birth weight status.


Assuntos
Displasia Broncopulmonar/epidemiologia , Recém-Nascido Pequeno para a Idade Gestacional , Recém-Nascido de muito Baixo Peso , Redução de Peso , Displasia Broncopulmonar/etiologia , Displasia Broncopulmonar/mortalidade , Estudos de Coortes , Bases de Dados Factuais , Feminino , Idade Gestacional , Humanos , Incidência , Mortalidade Infantil , Recém-Nascido , Masculino , Prevalência , Estudos Retrospectivos , Estados Unidos/epidemiologia
19.
J Anim Sci ; 84 Suppl: E60-72, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16582093

RESUMO

The splanchnic bed comprises the liver and the portal-drained viscera (PDV). The PDV, which include the stomach, intestines, pancreas, and spleen, represent 4 to 6% of BW, yet they account for 20 to 35% of whole-body protein turnover and energy expenditure. Because the PDV are the first to be exposed to the diet, their nutrient needs are met first. Consequently, the extraction of dietary nutrients, especially AA, by the intestine will have a critical influence on their availability to peripheral tissues and therefore, on whole body requirements. Moreover, the systemic availability of dietary AA is a key determinant of lean body growth rate. A complicating factor in the measurement of intestinal nutrient use is that the intestinal epithelial cells receive nutrients from 2 sources: the diet and the arterial circulation. However, combining measurements of the net portal balance with those of isotopic enrichments from enterally and intravenously administered stable isotope-labeled AA provides an in vivo model that can be used to determine the proportion of AA extracted by the intestine from either source. Using this technique in fed animals demonstrated that the PDV contribute significantly to the use of essential (>60% of threonine) and nonessential (>90% of glutamate) AA provided by the diet. The relative use by the PDV of individual AA from the diet and arterial inputs varies widely, and dietary AA are the preferred fuel over dietary glucose. Stable isotope-labeled AA also enable the determination of the metabolic fate of individual AA. Using this technique, studies have shown that an insufficient protein supply or the mode of feeding affects AA use by the PDV, and consequently, may affect whole-body growth.


Assuntos
Aminoácidos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Marcação por Isótopo/veterinária , Aminoácidos/biossíntese , Aminoácidos/fisiologia , Animais , Mucosa Gástrica/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Intestinos/microbiologia , Marcação por Isótopo/métodos , Fígado/metabolismo , Pâncreas/metabolismo , Biossíntese de Proteínas/fisiologia , Proteínas/metabolismo , Baço/metabolismo , Suínos
20.
Am J Physiol Gastrointest Liver Physiol ; 290(2): G293-300, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16166344

RESUMO

Premature infants receiving chronic total parenteral nutrition (TPN) due to feeding intolerance develop intestinal atrophy and reduced nutrient absorption. Although providing the intestinal trophic hormone glucagon-like peptide-2 (GLP-2) during chronic TPN improves intestinal growth and morphology, it is uncertain whether GLP-2 enhances absorptive function. We placed catheters in the carotid artery, jugular and portal veins, duodenum, and a portal vein flow probe in piglets before providing either enteral formula (ENT), TPN or a coinfusion of TPN plus GLP-2 for 6 days. On postoperative day 7, all piglets were fed enterally and digestive functions were evaluated in vivo using dual infusion of enteral ((13)C) and intravenous ((2)H) glucose, in vitro by measuring mucosal lactase activity and rates of apical glucose transport, and by assessing the abundances of sodium glucose transporter-1 (SGLT-1) and glucose transporter-2 (GLUT2). Both ENT and GLP-2 pigs had larger intestine weights, longer villi, and higher lactose digestive capacity and in vivo net glucose and galactose absorption compared with TPN alone. These endpoints were similar in ENT and GLP-2 pigs except for a lower intestinal weight and net glucose absorption in GLP-2 compared with ENT pigs. The enhanced hexose absorption in GLP-2 compared with TPN pigs corresponded with higher lactose digestive and apical glucose transport capacities, increased abundance of SGLT-1, but not GLUT-2, and lower intestinal metabolism of [(13)C]glucose to [(13)C]lactate. Our findings indicate that GLP-2 treatment during chronic TPN maintains intestinal structure and lactose digestive and hexose absorptive capacities, reduces intestinal hexose metabolism, and may facilitate the transition to enteral feeding in TPN-fed infants.


Assuntos
Peptídeos Semelhantes ao Glucagon/uso terapêutico , Hexoses/metabolismo , Síndromes de Malabsorção/prevenção & controle , Nutrição Parenteral Total/efeitos adversos , Algoritmos , Animais , Animais Recém-Nascidos , Dióxido de Carbono/metabolismo , DNA/biossíntese , DNA/genética , Peptídeo 2 Semelhante ao Glucagon , Glucose/administração & dosagem , Glucose/metabolismo , Transportador de Glucose Tipo 2/metabolismo , Íleo/metabolismo , Infusões Intravenosas , Jejuno/metabolismo , Cinética , Lactase/metabolismo , Consumo de Oxigênio/fisiologia , Transportador 1 de Glucose-Sódio/metabolismo , Suínos , Distribuição Tecidual
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