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1.
Front Pediatr ; 11: 1225960, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38034827

RESUMEN

Background: A growing body of evidence suggests an association between a higher maternal pre-pregnancy body mass index (BMI) and adverse long-term neurodevelopmental outcomes for their offspring. Despite recent attention to the effects of maternal obesity on fetal and neonatal brain development, changes in the brain microstructure of preterm infants born to mothers with pre-pregnancy obesity are still not well understood. This study aimed to detect the changes in the brain microstructure of obese mothers in pre-pregnancy and their offspring born as preterm infants using diffusion tensor imaging (DTI). Methods: A total of 32 preterm infants (born to 16 mothers with normal BMI and 16 mothers with a high BMI) at <32 weeks of gestation without brain injury underwent brain magnetic resonance imaging at term-equivalent age (TEA). The BMI of all pregnant women was measured within approximately 12 weeks before pregnancy or the first 2 weeks of gestation. We analyzed the brain volume using a morphologically adaptive neonatal tissue segmentation toolbox and calculated the major white matter (WM) tracts using probabilistic maps of the Johns Hopkins University neonatal atlas. We investigated the differences in brain volume and WM microstructure between preterm infants of mothers with normal and high BMI. The DTI parameters were compared among groups using analysis of covariance adjusted for postmenstrual age at scan and multiple comparisons. Results: Preterm infants born to mothers with a high BMI showed significantly increased cortical gray matter volume (p = 0.001) and decreased WM volume (p = 0.003) after controlling for postmenstrual age and multiple comparisons. We found a significantly lower axial diffusivity in the uncinate fasciculus (UNC) in mothers with high BMI than that in mothers with normal BMI (1.690 ± 0.066 vs. 1.762 ± 0.101, respectively; p = 0.005). Conclusion: Our study is the first to demonstrate that maternal obesity impacts perinatal brain development patterns in preterm infants at TEA, even in the absence of apparent brain injury. These findings provide evidence for the detrimental effects of maternal obesity on brain developmental trajectories in offspring and suggest potential neurodevelopmental outcomes based on an altered UNC WM microstructure, which is known to be critical for language and social-emotional functions.

2.
Front Microbiol ; 14: 1148466, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37256051

RESUMEN

This study aimed to evaluate the difference in gut microbiomes between preterm and term infants using third-generation long-read sequencing (Oxford Nanopore Technologies, ONT) compared with an established gold standard, Illumina (second-generation short-read sequencing). A total of 69 fecal samples from 51 term (T) and preterm (P) infants were collected at 7 and 28 days of life. Gut colonization profiling was performed by 16S rRNA gene sequencing using ONT. We used Illumina to validate and compare the patterns in 13 neonates. Using bioinformatic analysis, we identified features that differed between P and T. Both T1 and P1 microbiomes were dominated by Firmicutes (Staphylococcus and Enterococcus), whereas sequentially showed dominant transitions to Lactobacillus (p < 0.001) and Streptococcus in T2 (p = 0.001), and pathogenic bacteria (Klebsiella) in P2 (p = 0.001). The abundance of beneficial bacteria (Bifidobacterium and Lactobacillus) increased in T2 (p = 0.026 and p < 0.001, respectively). These assignments were correlated with the abundance at the species-level. Bacterial α-diversity increased in T (p = 0.005) but not in P (p = 0.156), and P2 showed distinct ß-diversity clustering than T2 (p = 0.001). The ONT reliably identified pathogenic bacteria at the genus level, and taxonomic profiles were comparable to those identified by Illumina at the genus level. This study shows that ONT and Illumina are highly correlated. P and T had different microbiome profiles, and the α- and ß-diversity varied. ONT sequencing has potential for pathogen detection in neonates in clinical settings.

3.
J Hazard Mater ; 452: 131200, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-36958158

RESUMEN

The preeminence of sulfonamide drug resistance genes in food waste (FW) and the increased utilization of high-strength organic FW in anaerobic digestion (AD) to enhance methane production have raised severe public health concerns in wastewater treatment plants worldwide. In this regard, the dissemination patterns of different sulfonamide resistance genes (sul1 and sul2) and their impact on the digester core microbiota during AD of FW leachate (FWL) were evaluated. The presence of various sulfonamide antibiotics (SAs) in FWL digesters improved the final methane yield by 37 % during AD compared with FWL digesters without SAs. Microbial population shifts towards hydrolytic, acidogenic, and acetogenic bacteria in the phyla Actinobacteriota, Bacteroidota, Chloroflexi, Firmicutes, Proteobacteria, and Synergistota occurred due to SA induced substrate digestion and absorption through active transport; butanoate, propanoate, and pyruvate metabolism; glycolysis; gluconeogenesis; the citrate cycle; and pentose phosphate pathway. The initial dominance of Methanosaeta (89-96 %) declined to 47-53 % as AD progressed and shifted towards Methanosarcina (40 %) in digesters with the highest SA concentrations at the end of AD. Dissemination of sul1 depended on class 1 integron gene (intl1)-based horizontal gene transfer to pathogenic members of Chloroflexi, Firmicutes, and Patescibacteria, whereas sul2 was transmitted to Synergistota independent of intl1. Low susceptibility and ability to utilize SAs during methanogenesis shielded methanogenic archaea against selection pressure, thus preventing them from interacting with sul or intl1 genes, thereby minimizing the risk of antibiotic resistance development. The observed emergence of cationic antimicrobial peptide, vancomycin, and ß-lactam resistance in the core microbiota during AD of FWL in the presence of SAs suggests that multidrug resistance caused by bacterial transformation could lead to an increase in the environmental resistome through wastewater sludge treatment.


Asunto(s)
Chloroflexi , Microbiota , Eliminación de Residuos , Anaerobiosis , Alimentos , Microbiota/genética , Aguas del Alcantarillado/microbiología , Bacterias/metabolismo , Sulfanilamida , Antibacterianos/metabolismo , Firmicutes , Metano/metabolismo , Reactores Biológicos
4.
Sensors (Basel) ; 21(16)2021 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-34450887

RESUMEN

Accurate measurement of bladder volume is an important tool for evaluating bladder function. In this study, we propose a wearable bladder scanner system that can continuously measure bladder volume in daily life for urinary patients who need urodynamic studies. The system consisted of a 2-D array, which included integrated forward-looking piezoelectric transducers with thin substrates. This study aims to estimate the volume of the bladder using a small number of piezoelectric transducers. A least-squares method was implemented to optimize an ellipsoid in a quadratic surface equation for bladder volume estimation. Ex-vivo experiments of a pig bladder were conducted to validate the proposed system. This work presents the potential of the approach for wearable bladder monitoring, which has similar measurement accuracy compared to the commercial bladder imaging system. The wearable bladder scanner can be improved further as electronic voiding diaries by adding a few more features to the current function.


Asunto(s)
Vejiga Urinaria , Dispositivos Electrónicos Vestibles , Animales , Humanos , Porcinos , Ultrasonografía , Vejiga Urinaria/diagnóstico por imagen
5.
PLoS One ; 14(11): e0225302, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31756221

RESUMEN

Telomeric repeat-containing RNAs (TERRAs) are long noncoding RNAs transcribed from subtelomeres toward telomeric repeat tracts, which have been implicated in telomere protection and heterochromatin formation. Genotoxic stress leads to upregulation of TERRAs. However, the mechanism of DNA damage-mediated TERRA induction remains elusive. Here, we treated HeLa cells with etoposide, a DNA double-strand break-generating agent, for various times and monitored the levels of TERRAs. Etoposide treatment led to a gradual time-dependent increase in TERRAs. Etoposide-mediated induction was evident in many TERRAs arising from various chromosome loci, including 20q and XpYp. Chromatin immunoprecipitation assays revealed no significant changes in the occupancy of RNA polymerase II at telomeres upon etoposide treatment. Interestingly, TERRAs arising from 20q, XpYp, 10q, and 13q degraded at slower rates in cells treated with etoposide, while degradation rates of TERRAs from many loci tested were nearly identical in both etoposide- and mock-treated cells. Telomere damage occurred from early time points of etoposide treatment, but telomere lengths and abundance of telomeric repeat-binding factor 2 (TRF2) at telomeres remained unchanged. In summary, etoposide treatment led to telomere damage and TERRA accumulation, but telomere lengths and TRF2-mediated telomere integrity were maintained. Etoposide-mediated TERRA accumulation could be attributed partly to RNA stabilization. These findings may provide insight into the post-transcriptional regulation of TERRAs in response to DNA damage.


Asunto(s)
Antineoplásicos Fitogénicos/efectos adversos , Daño del ADN , Etopósido/efectos adversos , ARN Largo no Codificante/genética , Telómero/genética , Supervivencia Celular/efectos de los fármacos , Cromosomas Humanos Par 20/genética , Cromosomas Humanos X/genética , Cromosomas Humanos Y/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HeLa , Humanos , Estabilidad del ARN , ARN Largo no Codificante/química , Telómero/efectos de los fármacos , Proteína 2 de Unión a Repeticiones Teloméricas
7.
Dig Dis Sci ; 64(3): 781-791, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30421375

RESUMEN

BACKGROUND: Injecting MSCs via blood vessel is most commonly used method, which has a major drawback of safety. The aim of our study was to evaluate efficacy using scaffold-loaded MSCs in acute liver failure model. METHOD: Acute liver failure was induced in mice using thioacetamide (TAA) (200 mg/kg, i.p) once a day for two consecutive days. The animals were divided in four acute liver failure groups: (1) TAA; (2) empty scaffold; (3) MSCs injected through tail vein; (4) MSC + Scaffold, scaffold loaded with MSCs, to evaluate the mortality and changes in liver function. Polylactic-co-glycolic acid scaffold alone and loaded with human MSCs was implanted on mice dorsum. RESULTS: TAA dose was titrated until one-third mortality rate was achieved. TAA (200 mg/kg) once daily for two consecutive days was injected to establish the acute liver failure model. The mortality of TAA and scaffold groups was 55.9% and 63.2%, respectively. Although, mortality of MSC-TV group decreased 14.7% as compared to TAA group (p = 0.200), MSC + Scaffold group had the lowest mortality (31.4%) (p = 0.013). Cells implanted in PLGA biomaterial were survived until 3 weeks, and their function was increased. Area of hepatic inflammation and necrosis was significantly reduced in MSC-TV and MSC + Scaffold groups; but there was no difference between the two groups. Gene expressions related to inflammation were significantly decreased in MSC-TV and MSC + Scaffold groups compared to TAA group. In MSC + Scaffold group, no migration of stem cells to liver tissue was observed. Although, not all cells in scaffold were stained, some of them were differentiated into hepatocyte-like cells which stained positive for PAS and CYP2E1 antibody. CONCLUSION: Scaffold loaded with MSCs showed protective effects via paracrine signaling on acute liver failure model.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/cirugía , Fallo Hepático Agudo/cirugía , Regeneración Hepática , Hígado/metabolismo , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/metabolismo , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Andamios del Tejido/química , Animales , Biomarcadores/metabolismo , Diferenciación Celular , Movimiento Celular , Proliferación Celular , Células Cultivadas , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Citocromo P-450 CYP2E1/metabolismo , Modelos Animales de Enfermedad , Humanos , Hígado/patología , Fallo Hepático Agudo/inducido químicamente , Fallo Hepático Agudo/metabolismo , Fallo Hepático Agudo/patología , Ratones Endogámicos C57BL , Necrosis , Comunicación Paracrina , Fenotipo , Tioacetamida
8.
J Korean Med Sci ; 33(43): e272, 2018 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-30344462

RESUMEN

BACKGROUND: In Korea, the breastfeeding (BF) rate of infants aged 6 months or more is drastically decreasing, and this phenomenon is particularly worrisome for the future health of the population. The present study aimed to identify an antenatal strategy for initiation and continuation of human BF, and to identify how Baby-Friendly Hospitals (BFHs) may positively influence the intention to breastfeed. METHODS: A total of 414 pregnant Korean antenatal women were surveyed using questionnaires to determine current knowledge of the benefits of human breast milk, whether they planned to breastfeed after delivery, to continue BF after reinstatement in the workforce, are willing to abide by rooming-in care for infants, and plan to give birth at BFHs. RESULTS: We found that planning room-in care, greater awareness of BF benefits for infant and mother, participation in antenatal education programs, and provision of BF facilities in the workplace were positively associated with plans for exclusive breastfeeding (EBF) and longer BF duration. The mothers who planned to give birth at BFHs also desired to breastfeed immediately after birth, implement in-room care, continue BF at their workplace, participate in antenatal BF educational programs, and were more aware of the benefits of BF. CONCLUSION: If the beneficial effects of BFHs were well known to individuals, these would enhance the success rate of BF in Korea. Antenatal education and consequent acquisition of better knowledge of the benefits of BF are important for increasing the rate of BF practices.


Asunto(s)
Lactancia Materna/estadística & datos numéricos , Madres/psicología , Adulto , Femenino , Hospitales , Humanos , Lactante , Estudios Longitudinales , Oportunidad Relativa , Embarazo , Atención Prenatal , Encuestas y Cuestionarios , Lugar de Trabajo , Adulto Joven
9.
J Matern Fetal Neonatal Med ; 31(1): 7-13, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27334257

RESUMEN

OBJECTIVE: There is little follow-up data in preterm infants from mothers with systemic lupus erythematosus (SLE). The aim of this study was to determine maternal outcomes and compare neonatal outcomes in preterm and term infants born to mothers with SLE. METHODS: This study is a prospective study in a tertiary medical care center and clinical research center for rheumatoid arthritis. Demographic data, clinical features, laboratory findings, treatment and complications in 77 pregnant SLE patients were prospectively evaluated from 2007 to 2013. RESULTS: Ninety-two infants (44 males and 48 females including four sets of twins) from 77 mothers with SLE were enrolled. Multivariate logistic analysis indicated that flares were significantly associated with antiphospholipid antibodies of lupus anticoagulant during pregnancy (p = 0.009) and preterm birth (p = 0.017). Compared with term infants, preterm infants had significantly higher antinuclear antibodies (ANA) positivity (p = 0.001) at 12 months of age in multivariate logistic analysis. CONCLUSION: Preterm birth is associated with maternal flares and persistent ANA positivity at 12 months of life in infants born to mothers with SLE.


Asunto(s)
Anticuerpos Antinucleares/sangre , Inhibidor de Coagulación del Lupus/sangre , Lupus Eritematoso Sistémico/complicaciones , Nacimiento Prematuro/inmunología , Adulto , Femenino , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/inmunología , Masculino , Embarazo , Nacimiento Prematuro/sangre , Estudios Prospectivos , Brote de los Síntomas
10.
Early Hum Dev ; 93: 47-55, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26789556

RESUMEN

BACKGROUND: Despite previous efforts to explain the general advantages of female fetuses over males regarding health, sex-related differences in the dynamics or complexity of fetal heart rate (FHR) variability and FHR maturation patterns have not yet been identified. AIM: To make linear and nonlinear comparisons of antepartum FHR indices, dynamics, complexity, and reactivity to the non-stress test (NST) and vibroacoustic-stimulation test (VAST) in male and female fetuses. STUDY DESIGN: A total of 3835 singleton term deliveries without maternal and fetal complications were divided into female (n=1849) and male (n=1986) groups, and subjected to comparison and analyses. SUBJECTS: Linear FHR indices, approximate entropy (ApEn), sample entropy (SampEn), short-term/long-term exponents (α1/α2), correlation dimension (CD), NST and VAST criteria, and modified nonlinear reactive criteria (MNRC) were used to evaluate outcomes. RESULTS: ApEn was consistently higher in female fetuses than in male ones. ApEn in female fetuses was maximal at 29-30 gestational weeks, while the increase in ApEn was delayed in male fetuses but more rapid, reaching its peak at 31-32 gestational weeks. In both sexes, CD increased up to term, and α2 rapidly decreased up to 31-32weeks in an analogous manner. The two sexes differed significantly in response to VAST at <31 gestational weeks and there was a structural difference in reactive patterns under MNRC. CONCLUSIONS: Female fetuses exhibit greater heart rate dynamics in early gestational periods, suggesting that their cardiovascular system matures earlier than that of males. Male fetuses undergo a compensatory period of rapid change to catch up with females at term.


Asunto(s)
Corazón Fetal/fisiología , Frecuencia Cardíaca , Adulto , Femenino , Corazón Fetal/crecimiento & desarrollo , Humanos , Masculino , Embarazo , Factores Sexuales
11.
Placenta ; 36(12): 1474-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26602608

RESUMEN

INTRODUCTION: We analyzed fetal heart rate (FHR) parameters, dynamics, and outcomes in pregnancies with asymptomatic partial placental abruption (PPA) compared with those in normal pregnancies. METHODS: We examined nonstress test (NST) data acquired from 2003 to 2012 at our institution. Normal pregnancies (N = 170) and PPA cases (N = 17) were matched for gestational age, fetal sex, and mean FHR. NSTs were performed at 33-42 weeks of gestation. FHR parameters obtained from the NST and perinatal outcomes were analyzed using linear methods. Nonlinear indices, including approximate entropy (ApEn), sample entropy (SampEn), short-term and long-term scaling exponents (α1 and α2), and correlation dimension (CD), were used to interpret FHR dynamics and system complexity. The area under a receiver operating characteristic curve (AUC) was used to evaluate the nonlinear indices. RESULTS: There were no significant differences in general characteristics and FHR parameters between the PPA and control groups. However, gestational age at delivery, birth weight, 5-min Apgar scores, ApEn, SampEn, and CD were significantly lower in the PPA group than in the control group (P < 0.05). The long-term scaling exponent (α2) and crossover index (α2/α1) of the PPA fetuses were significantly higher than those of the controls (P < 0.01). A multiple regression model showed better performance in predicting PPA (AUC, 0.92; sensitivity 82.35%; specificity, 94.12%). DISCUSSION: Nonlinear dynamic indices of FHR in asymptomatic PPA were qualitatively different from those in normal pregnancies, whereas the conventional FHR parameters were not significantly different.


Asunto(s)
Desprendimiento Prematuro de la Placenta/fisiopatología , Frecuencia Cardíaca Fetal/fisiología , Adulto , Femenino , Edad Gestacional , Humanos , Masculino , Dinámicas no Lineales , Embarazo , Adulto Joven
12.
PLoS One ; 10(9): e0138460, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26383864

RESUMEN

Directed methods for differentiating human embryonic stem cells (hESCs) into dopaminergic (DA) precursor cells using stromal cells co-culture systems are already well established. However, not all of the hESCs differentiate into DA precursors using these methods. HSF6, H1, H7, and H9 cells differentiate well into DA precursors, but CHA13 and CHA15 cells hardly differentiate. To overcome this problem, we modified the differentiation system to include a co-culturing step that exposes the cells to noggin early in the differentiation process. This was done using γ-irradiated noggin-overexpressing CF1-mouse embryonic fibroblasts (MEF-noggin) and MS5 stromal cells (MS5-noggin and MS5-sonic hedgehog). After directed differentiation, RT-PCR analyses revealed that engrailed-1 (En-1), Lmx1b, and Nurr1, which are midbrain DA markers, were expressed regardless of differentiation stage. Moreover, tyrosine hydroxylase (Th) and an A9 midbrain-specific DA marker (Girk2) were expressed during differentiation, whereas levels of Oct3/4, an undifferentiated marker, decreased. Immunocytochemical analyses revealed that protein levels of the neuronal markers TH and TuJ1 increased during the final differentiation stage. These results demonstrate that early noggin exposure may play a specific role in the directed differentiation of DA cells from human embryonic stem cells.


Asunto(s)
Proteínas Portadoras/metabolismo , Diferenciación Celular/genética , Neuronas Dopaminérgicas/metabolismo , Fibroblastos/metabolismo , Células Madre Embrionarias Humanas/metabolismo , Células del Estroma/metabolismo , Animales , Proteínas Portadoras/genética , Técnicas de Cocultivo , Neuronas Dopaminérgicas/citología , Factor 8 de Crecimiento de Fibroblastos/genética , Factor 8 de Crecimiento de Fibroblastos/metabolismo , Fibroblastos/citología , Canales de Potasio Rectificados Internamente Asociados a la Proteína G/genética , Canales de Potasio Rectificados Internamente Asociados a la Proteína G/metabolismo , Células Madre Embrionarias Humanas/citología , Humanos , Proteínas con Homeodominio LIM/genética , Proteínas con Homeodominio LIM/metabolismo , Ratones , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Células del Estroma/citología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Tirosina 3-Monooxigenasa/genética , Tirosina 3-Monooxigenasa/metabolismo
13.
J Perinat Med ; 43(6): 741-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25178901

RESUMEN

AIM: To examine how complex and irregular fetal heart rate (FHR) dynamics differ between fetuses of normal pregnancies and those of pregnancies complicated by maternal anemia (MA), and to place this in the context of high-risk pregnancies. METHODS: Our study population consisted of 97 pregnant women affected by MA, 118 affected by pregnancy-induced hypertension (PIH), 88 affected by gestational diabetes mellitus (GDM), 53 with preterm premature rupture of membranes (pPROM), and 356 normal pregnancies as controls. We calculated approximate entropy (ApEn), sample entropy (SampEn), and correlation dimension (CD) to quantify irregularity and the chaotic dynamics of each FHR time series. RESULTS: The ApEn in the fetuses of the MA and PIH groups was significantly lower than that of the normal controls (P<0.05). The SampEn was significantly lower in the high-risk groups, except for the pPROM group, than in the normal controls (P<0.05). The CD in the PIH and severe MA groups was significantly lower than that of the normal controls (P<0.05, respectively). In the MA group, the dynamic indices showed a highly significant positive correlation with hemoglobin (Hb) levels (P<0.0001). CONCLUSION: The decreased complexity and/or irregularity in the FHR from pregnancies with MA may reflect abnormalities in the complex, integrated cardiovascular control. The irregularity and complexity of the FHR increased together with Hb levels in pregnancies with MA. Our data suggest that the integrity of the nervous system in the fetuses compromised by severe MA might result directly in adverse outcomes.


Asunto(s)
Anemia/fisiopatología , Frecuencia Cardíaca Fetal/fisiología , Complicaciones Hematológicas del Embarazo/fisiopatología , Embarazo de Alto Riesgo/fisiología , Adulto , Estudios de Casos y Controles , Diabetes Gestacional/fisiopatología , Femenino , Rotura Prematura de Membranas Fetales/fisiopatología , Humanos , Hipertensión Inducida en el Embarazo/fisiopatología , Masculino , Embarazo
14.
Blood Cells Mol Dis ; 53(1-2): 1-10, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24594313

RESUMEN

Reticulocytes contain both RNA and micro-organelles and represent the last stage of erythropoiesis before full maturation to red blood cells (RBCs). Even though there is continuing synthesis of hemoglobin and membrane-bound proteins in reticulocytes, the small amount of RNA that they contain has been regarded as non-functional residual material. Here we show that this residual RNA is both functional and essential for further reticulocyte maturation. Reticulocytes from which the remnant RNA had been removed by exposure to RNase did not survive or mature into RBCs in either humans or mice. Conversely, reticulocytes treated with an RNase Inhibitor were able to form normal biconcave cells. Similarly, poor survival was also seen in reticulocytes in which protein synthesis had been blocked. To identify the signaling pathways involved we isolated RNAs in reticulocytes versus those present in fully matured erythroblasts cultured from hematopoietic stem cells. RNAs found in erythroblasts were related to exocytosis, metabolism, and signal transduction all of which are critical for maturation through reticulocyte and into a fully mature, biconcave erythrocyte. Our results suggest that the mRNA in reticulocytes has to be translated into novel proteins that act to preserve mitochondria and maintain cell membrane integrity as reticulocytes mature. These results enhance our understanding of the final stage of erythropoiesis and may clarify why in vitro-generated reticulocytes for transfusion purposes survive poorly.


Asunto(s)
ARN/genética , ARN/metabolismo , Reticulocitos/metabolismo , Adulto , Anciano , Animales , Transporte Biológico , Diferenciación Celular , Separación Celular , Supervivencia Celular/efectos de los fármacos , Endorribonucleasas/metabolismo , Eritrocitos/citología , Eritrocitos/metabolismo , Eritrocitos/ultraestructura , Eritropoyesis , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Mitocondrias/metabolismo , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Reticulocitos/citología , Reticulocitos/ultraestructura , Transducción de Señal
16.
Early Hum Dev ; 89(2): 101-6, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22959071

RESUMEN

BACKGROUND: It has been reported that breech fetuses have inferior neurological outcomes regardless of mode of delivery, raising the possibility that in utero neurological impairment is more frequent in breech fetuses, possibly contributing to malpresentation. AIMS: To assess differences between the cardiovascular autonomic nervous systems (ANSs) of breech and cephalic fetuses using nonlinear dynamic indices of fetal heart rate (FHR) variability. STUDY DESIGN AND SUBJECTS: This study included 86 fetuses with breech presentation and 173 fetuses with cephalic presentation, with no other maternal or fetal problems. We analyzed FHR variability and spectral indices as markers of ANS behavior. We used nonlinear dynamic indices to represent the complexity of heart rate regulation, as well as correlation dimension as a chaotic index of the cardiovascular control system. RESULTS: One of FHR parameters (Mean minute range) was significantly lower in breech than cephalic fetuses (p=0.0294). However, there were no other significant differences in any linear or nonlinear indices, nor in clinical outcomes, between breech and cephalic fetuses. CONCLUSION: Our data suggest that breech fetuses have neither more active ANS nor less active complexity control systems than do cephalic fetuses. This indicates that the neurologic maturation of breech fetuses is not inferior to cephalic ones. The practical implication of these findings is that the nervous system integrity of breech fetuses may not result directly in neonatal complications.


Asunto(s)
Presentación de Nalgas/fisiopatología , Frecuencia Cardíaca Fetal , Dinámicas no Lineales , Sistema Nervioso Autónomo/fisiopatología , Estudios de Casos y Controles , Femenino , Corazón Fetal/inervación , Humanos , Embarazo
17.
Taiwan J Obstet Gynecol ; 51(3): 397-401, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23040924

RESUMEN

OBJECTIVE: This study was conducted to assess the relative significance of the amplitude versus the duration of accelerations in non-stress test (NST) analysis. MATERIALS AND METHODS: A total of 3055 normal fetal heart rate (FHR) tracings at 30-42 weeks' gestation were analyzed by automated FHR analyzing software. Accelerations were classified as one of four combinations of amplitude and duration: 15 bpm-15 seconds (Acc15-15), 15 bpm-10 seconds (Acc15-10), 10 bpm-15 seconds (Acc10-15) and 10 bpm-10 seconds (Acc10-10). We estimated the correlation among the FHR acceleration combinations using correlation analysis based on linear regression models. RESULTS: Linear regression models demonstrated statistically significant linear associations between Acc15-15 and Acc15-10 (r(2) = 0.998, p < 0.0001) and between Acc10-10 and Acc10-15 (r(2) = 0.989, p < 0.0001). There was significant association based on amplitude and relatively low correlation based on duration (Pearson correlation coefficient = 0.99 between Acc10-10 and Acc10-15, and 0.99 between Acc15-15 and Acc15-10). In the relationships of the FHR-work values, amplitude was a more important component of FHR acceleration than duration [Acc10-10 (1.67 beat) < Acc10-15 (2.50 beats) = Acc15-10 (2.50 beats) < Acc15-15 (3.75 beats)]. CONCLUSION: Amplitude was a more significant component of FHR acceleration than duration in the computerized analysis of NST.


Asunto(s)
Aceleración , Monitoreo Fetal/métodos , Frecuencia Cardíaca Fetal/fisiología , Procesamiento Automatizado de Datos , Femenino , Edad Gestacional , Humanos , Modelos Lineales , Embarazo , Factores de Tiempo
18.
Kaohsiung J Med Sci ; 28(8): 423-8, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22892163

RESUMEN

The objectives of this study were to provide new parameters to better understand labor curves, and to provide a model to predict the time to full cervical dilation (CD). We studied labor curves using the retrospective records of 594 nulliparas, including at term, spontaneous labor onset, and singleton vertex deliveries of normal birth weight infants. We redefined the parameters of Friedman's labor curve, and applied a three-parameter model to the labor curve with a logistic model using the genetic algorithm and the Newton-Raphson method to predict the time necessary to reach full CD. The genetic algorithm is more effective than the Newton-Raphson method for modeling labor progress, as demonstrated by its higher accuracy in predicting the time to reach full CD. In addition, we predicted the time (11.4 hours) to reach full CD using the logistic labor curve using the mean parameters (the power of CD = 0.97 cm/hours, a midpoint of the active phase = 7.60 hours, and the initial CD = 2.11 cm). Our new parameters and model can predict the time to reach full CD, which can aid in the forecasting of prolonged labor and the timing of interventions, with the end goal being normal vaginal birth.


Asunto(s)
Algoritmos , Primer Periodo del Trabajo de Parto , Modelos Logísticos , Adulto , Femenino , Humanos , Recién Nacido , Embarazo , Estudios Retrospectivos
19.
J Korean Med Sci ; 27(7): 794-8, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22787377

RESUMEN

The purpose of this study was to investigate the feasibility of different fetal heart rate (FHR) ranges in the nonstress test (NST) and to better understand the meaning of mild bradycardia and/or tachycardia without non-reassuring patterns. We employed the heredity to show that mild bradycardia (100-119 beats per minute, bpm) and mild tachycardia (161-180 bpm) regressed to the normal FHR range (120-160 bpm). We used linear regression to analyze FHR data from FHR tracings recorded 10 min before (NST, as the predictor) and 10 min after vibroacoustic stimulation testing (as the dependent variable). Acceleration for 15 bpm-15 seconds (Acc1515) and deceleration for 15 bpm-15 seconds (Dec1515) in the NST were also analyzed for each group. The slope of the best-fit line was the largest in the mild bradycardia group and the smallest in the normal range group. Dec1515 was most prominent in mild tachycardia and both the mild bradycardia and tachycardia groups regressed towards the mean FHR range. Therefore, we propose that both mild bradycardia and tachycardia of FHR in non-acute situations (range between 100 and 180 bpm) are not regarded a pathologic signal for clinical use.


Asunto(s)
Monitoreo Fetal , Frecuencia Cardíaca Fetal/fisiología , Estimulación Acústica , Bradicardia/fisiopatología , Femenino , Humanos , Embarazo , Tercer Trimestre del Embarazo , Análisis de Regresión , Taquicardia/fisiopatología
20.
J Obstet Gynaecol Res ; 38(2): 358-63, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22176493

RESUMEN

AIM: The purpose of the present study was to compare and analyze differences in antepartal fetal heart rate (FHR) parameters during pregnancy and pregnancy outcomes in normal fetuses and fetuses with nuchal cord (NC). MATERIAL AND METHODS: We surveyed all non-stress test (NST) data acquired using a computerized FHR analysis system at Hanyang University Hospital between 2005 and 2008, and selected 150 cases that had NC. NSTs were performed between 37 and 42 weeks of gestation. Subjects were divided into three groups by the number of NCs: no NC and normal (n = 300), single (n = 124) and multiple NCs (n = 26). Neonatal outcomes were compared, and FHR parameters analyzed using computerized fetal monitoring system. RESULTS: FHR variability, with respect to amplitude (AMP) and mean minute range (MMR), was lower in the multiple NCs group than in the normal group (18.04 ± 0.38 vs 14.54 ± 1.10 bpm, P = 0.0207; 55.69 ± 1.22 vs 44.35 ± 3.41 ms, P = 0.0145, respectively). There were no other statistically significant differences of FHR parameters between the three groups. Baby weight was significantly lower in the multiple NCs group than in the normal group (3317 ± 24 vs 3054 ± 55; P = 0.0008), and there were no other significant differences between the groups. CONCLUSION: Computerized analysis of FHR would be helpful to assess fetal status, especially in cases of multiple NCs. Multiple NCs may be a subliminal risk factor for the babies even though they present no complications at delivery.


Asunto(s)
Frecuencia Cardíaca Fetal , Cordón Nucal/fisiopatología , Femenino , Humanos , Embarazo , Estudios Retrospectivos , Factores de Riesgo
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