RESUMEN
OBJECTIVES: To assess neonatal platelet counts by comparing alloimmunised pregnancies from a Norwegian screening and intervention study with subsequent pregnancies from the same women. DESIGN: Prospective observational follow-up study. SETTING: A university hospital. POPULATION: HPA-1a immunised women from a large Norwegian screening study that gave birth to one or more children after the screening study ended (2004-2012). METHODS: Follow-up of maternal anti-HPA-1a antibody levels and neonatal platelet counts from the screening pregnancies were compared with subsequent pregnancies. None of the women received antenatal intravenous immunoglobulin (IVIG) treatment and neonatal platelet counts were therefore comparable. MAIN OUTCOME MEASURES: Change in neonatal platelet counts from one HPA-1a incompatible pregnancy to the next. Maternal anti-HPA-a1 antibody levels from one HPA-1a incompatible pregnancy to the next. RESULTS: Forty-five incompatible subsequent pregnancies were identified. Overall, the neonatal platelet count in the subsequent pregnancy was improved (18%), unchanged (52%), or worse (30%), compared with the corresponding screening pregnancy. There was one case of fetal intracranial haemorrhage (ICH) identified in the screening (intrauterine fetal death detected at 30 weeks of gestation) and no ICH cases recorded for the subsequent pregnancies. In cases where the platelet count was lower in the subsequent pregnancy, the maternal anti-HPA-1a antibody level was higher compared with the screening pregnancy. In comparison, the maternal antibody level was lower in subsequent pregnancies where the platelet count improved. CONCLUSIONS: In contrast to what is often stated, we found that the neonatal platelet count was increased or unchanged in the majority of subsequent pregnancies of HPA-1a-immunised women.
Asunto(s)
Trombocitopenia Neonatal Aloinmune/etiología , Adulto , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido , Masculino , Modelos Estadísticos , Noruega/epidemiología , Embarazo , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Trombocitopenia Neonatal Aloinmune/diagnóstico , Trombocitopenia Neonatal Aloinmune/epidemiologíaRESUMEN
In this comparative cross-sectional study, possible associations between maternal anti-HLA class I antibodies and birth weight in neonatal thrombocytopenia are explored. Although commonly detected in pregnancies and generally regarded as harmless, it has been suggested that such antibodies might be associated with fetal and neonatal alloimmune thrombocytopenia (FNAIT). As a link between FNAIT due to human platelet antigen 1a-specific antibodies and reduced birth weight in boys has previously been demonstrated, we wanted to explore whether maternal anti-HLA class I antibodies might also affect birth weight. To examine this, suspected cases of FNAIT referred to the Norwegian National Unit for Platelet Immunology during the period 1998-2009 were identified. Pregnancies where the only finding was maternal anti-HLA class I antibodies were included. An unselected group of pregnant women participating in a prospective study investigating maternal-fetal hemodynamics at the University Hospital North Norway during the years 2006-2010 served as controls. Twenty-nine percent of controls had anti-HLA class I antibodies. The thrombocytopenic neonates had a significantly lower adjusted birth weight (linear regression, P=0.036) and significantly higher odds of being small for gestational age (OR=6.72, P<0.001) compared with controls. Increasing anti-HLA class I antibody levels in the mother were significantly associated with lower birth weight and placental weight among thrombocytopenic neonates, but not among controls. These results indicate that maternal anti-HLA class I antibodies in thrombocytopenic neonates are associated with reduced fetal growth. Further studies are needed to test if placental function is affected.
Asunto(s)
Antígenos de Histocompatibilidad Clase I/inmunología , Recién Nacido de Bajo Peso/inmunología , Isoanticuerpos/inmunología , Intercambio Materno-Fetal/inmunología , Placenta/inmunología , Trombocitopenia Neonatal Aloinmune/inmunología , Adulto , Estudios Transversales , Femenino , Antígenos de Histocompatibilidad Clase I/sangre , Humanos , Recién Nacido de Bajo Peso/sangre , Isoanticuerpos/sangre , Placenta/metabolismo , Embarazo , Estudios Retrospectivos , Trombocitopenia Neonatal Aloinmune/sangreRESUMEN
The implementation of an antenatal screening programme for neonatal alloimmune thrombocytopenia (NAIT) is currently under debate. We evaluated the detection rate for NAIT in a nonscreened population of 661,200 births where NAIT was diagnosed on clinical indication. We did a cross-sectional comparison with a population of 100,448 human platelet antigen 1a (HPA1a)-screened pregnancies from three of the five health regions in Norway. In a nonscreening situation, 7.5 cases of NAIT were detected per year compared with 53 cases when screening was applied. The detection rate of NAIT in Norway was therefore 14% of the expected rate.
Asunto(s)
Antígenos de Plaqueta Humana/sangre , Diagnóstico Prenatal/métodos , Trombocitopenia Neonatal Aloinmune/diagnóstico , Estudios Transversales , Diagnóstico Precoz , Femenino , Humanos , Recién Nacido , Integrina beta3 , Noruega/epidemiología , Reacción en Cadena de la Polimerasa , Embarazo , Trombocitopenia Neonatal Aloinmune/epidemiologíaRESUMEN
OBJECTIVES: Evaluation of a new surface treatment method to obtain a good bond strength between a luting composite and several ceramics. METHODS: Specimen preparation and test procedure were done according to ISO 10477 Amendment 1. The surfaces of Empress II, InCeram-Alumina, InCeram-Zirconia and Frialit (ZrO2) were ground under water-cooling with 400 grit grinding paper, afterwards polished with 800 grit and air-dried. Each ceramic material investigated was divided into three groups of 10 specimens each. Group 1 was flame-treated with the PyrosilPen for 2.5 s, group 2 for 5 s and group 3 for 10 s/cm(2). After the flame treatment, a methacryl silane was applied followed by a luting composite. Prior to measuring shear bond strength, the specimens were thermocycled 5,000 times in a water-bath between +5 and +55 degrees C. Furthermore, SEM- and Fourier-transform infrared spectrophotometer (FT-IR)-investigations were done. As a control, Empress II etched and silaned was used. RESULTS: Shear bond strength measurements indicated that the optimal treatment time was 5 s/cm(2). Regarding this time the following bond strength values between the luting composite and the various ceramics were obtained: Empress II 23 (5)MPa, InCeram-Alumina 23 (5)MPa, InCeram-Zirconia 13 (8)MPa, and Frialit 16 (6)MPa. The control achieved 27 (6)MPa. On all surfaces of the flamed specimens Si could be detected by FT-IR.Significance. The PyrosilPen-Technology is an easy and effective method for surface-treating silicate, aluminum oxide and zirconium oxide ceramics to obtain good bonding to luting composites.
Asunto(s)
Recubrimiento Dental Adhesivo/instrumentación , Recubrimiento Dental Adhesivo/métodos , Porcelana Dental , Óxido de Aluminio , Instrumentos Dentales , Análisis del Estrés Dental , Compuestos de Litio , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Cementos de Resina , Resistencia al Corte , Silanos , Espectroscopía Infrarroja por Transformada de Fourier , CirconioRESUMEN
Batch cultures of photoautotrophic cell suspensions of Chenopodium rubrum L., growing in an inorganic medium on CO2 under a daily balanced light-dark regime of 16: 8 h could be maintained for approximately 100 d without subcultivation. The long-lived cultures showed an initial cell division phase of 4 weeks, followed by a stationary phase of another 4 weeks, after which ageing and progressive cell death reduced the number of living cells and the cultures usually expired after another 3-4 weeks. These developmental phases of the cell culture were characterised with respect to photosynthetic performance, dark respiration, content of phytohormones and capacity of cell division. Cell division of the majority of the cells finished in the G1- or G0-phase of the cell cycle, caused by a pronounced decline in the endogenous levels of auxin and cytokinins. Supply of these growth factors to resting cells resulted in resumption of cytokinesis, at least by some of the cells. However, responsiveness to the phytohormones declined during the stationary phase, and subcultivation was no longer possible beyond day 60 when the phases of ageing and death commenced. Ageing was characterised by a further decline in the photosynthetic capacity of the cells, by a climacteric enhancement of dark respiration, but also by a slight increase in the level of IAA and cytokinins concomitant with a decrease in ethylene. Similarities and differences between the development of batch-cultured photoautotrophic cells of C. rubrum and that of a leaf are discussed with respect to using the cell culture as a model for a leaf.