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1.
Ultrasound Obstet Gynecol ; 62(2): 248-254, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36971026

RESUMEN

OBJECTIVE: To examine the relationship between umbilical cord insertion site, placental pathology and adverse pregnancy outcome in a cohort of normal and complicated pregnancies. METHODS: Sonographic measurement of the cord insertion and detailed placental pathology were performed in 309 participants. Associations between cord insertion site, placental pathology and adverse pregnancy outcome (pre-eclampsia, preterm birth, small-for-gestational age) were examined. RESULTS: A total of 93 (30%) participants were identified by pathological examination to have a peripheral cord insertion site. Only 41 of the 93 (44%) peripheral cords were detected by prenatal ultrasound. Peripherally inserted cords were associated significantly (P < 0.0001) with diagnostic placental pathology (most commonly with maternal vascular malperfusion (MVM)); of which 85% had an adverse pregnancy outcome. In cases of isolated peripheral cords, without placental pathology, the incidence of adverse outcome was not statistically different when compared to those with central cord insertion and no placental pathology (31% vs 18%; P = 0.3). A peripheral cord with an abnormal umbilical artery (UA) pulsatility index (PI) corresponded to an adverse outcome in 96% of cases compared to 29% when the UA-PI was normal. CONCLUSIONS: This study demonstrates that peripheral cord insertion is often part of the spectrum of findings of MVM disease and is associated with adverse pregnancy outcome. However, adverse outcome was uncommon when there was an isolated peripheral cord insertion and no placental pathology. Therefore, additional sonographic and biochemical features of MVM should be sought when a peripheral cord is observed. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Placenta , Resultado del Embarazo , Cordón Umbilical , Femenino , Humanos , Recién Nacido , Embarazo , Placenta/patología , Nacimiento Prematuro , Arterias Umbilicales/diagnóstico por imagen , Cordón Umbilical/diagnóstico por imagen , Cordón Umbilical/patología
3.
Ultrasound Obstet Gynecol ; 57(1): 70-74, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33030756

RESUMEN

OBJECTIVE: To evaluate the feasibility of using umbilical artery (UA) Doppler waveforms to measure fetal heart rate (FHR) short-term variation (STV) across gestation. METHODS: This was a prospective longitudinal study, conducted at two study sites, of 195 pregnancies considered low risk. Pulsed-wave Doppler of the UAs was performed at 4-weekly intervals, between 14 and 40 weeks of gestation, using a standardized imaging protocol. Up to 12 consecutive UA Doppler waveforms were analyzed using offline processing software. FHR STV was calculated using average R-R intervals extracted from the waveforms and baseline corrected for FHR. RESULTS: Baseline-corrected FHR STV increased significantly with gestational age (conditional R2 = 0.37; P < 0.0001) and was correlated inversely with FHR (conditional R2 = 0.54; P < 0.0001). The STV ranged (median (interquartile range)) from 3.5 (2.9-4.1) ms at 14-20 weeks' gestation to 6.3 (4.8-7.7) ms at 34-40 weeks' gestation. The change in heart rate STV did not differ between study sites or individual sonographers. CONCLUSIONS: UA Doppler waveforms offer a robust and feasible method to derive STV of the FHR. It should be emphasized that the UA Doppler-derived STV is not interchangeable with measurements derived with computerized cardiotocography. Accordingly, further investigations are needed to validate associations with outcome, in order to determine the value of concurrent fetal cardiovascular and heart rate evaluations that are possible with the technique described here. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Retardo del Crecimiento Fetal/diagnóstico por imagen , Frecuencia Cardíaca Fetal , Arteria Cerebral Media/diagnóstico por imagen , Ultrasonografía Doppler/métodos , Arterias Umbilicales/diagnóstico por imagen , Adulto , Cardiotocografía/métodos , Femenino , Edad Gestacional , Humanos , Recién Nacido , Estudios Longitudinales , Masculino , Arteria Cerebral Media/embriología , Embarazo , Estudios Prospectivos , Ultrasonografía Prenatal
4.
Neurobiol Aging ; 36(2): 638-47, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25311279

RESUMEN

Murine models of Alzheimer's disease (AD) have been used to draw associations between atrophy of neural tissue and underlying pathology. In this study, the early-onset TgCRND8 mouse model of AD and littermate controls were scanned longitudinally with in vivo manganese-enhanced MRI (MEMRI) before and after the onset of amyloid plaque deposition at 12 weeks of age. Separate cohorts of mice were scanned at 1 week (ex vivo imaging) and 4 weeks (MEMRI) of age to investigate early life alterations in the brain. Contrary to our expectations, differences in neuroanatomy were found in early post-natal life, preceding plaque deposition by as much as 11 weeks. Many of these differences remained at all imaging time points, suggesting that they were programmed early in life and were unaffected by the onset of pathology. Furthermore, rather than showing atrophy, many regions of the TgCRND8 brain grew at a faster rate compared to controls. These regions contained the greatest density of amyloid plaques and reactive astrocytes. Our findings suggest that pathological processes as well as an alteration in brain development influence the TgCRND8 neuroanatomy throughout the lifespan.


Asunto(s)
Enfermedad de Alzheimer/patología , Encéfalo/crecimiento & desarrollo , Encéfalo/patología , Envejecimiento/metabolismo , Envejecimiento/patología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/fisiopatología , Animales , Atrofia , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Imagen por Resonancia Magnética/métodos , Ratones Transgénicos , Placa Amiloide/metabolismo , Placa Amiloide/patología
5.
J Phys Chem B ; 110(14): 7171-7, 2006 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-16599482

RESUMEN

High-resolution solid-state (7)Li NMR was used to characterize the structure and dynamics of lithium ion transport in monoclinic Li(3)V(2)(PO(4))(3). Under fast magic-angle spinning (MAS) conditions (25 kHz), three resonances are clearly resolved and assigned to the three unique crystallographic sites. This assignment is based on the Fermi-contact delocalization interaction between the unpaired d-electrons at the vanadium centers and the lithium ions. One-dimensional variable-temperature NMR and two-dimensional exchange spectroscopy (EXSY) are used to probe Li mobility between the three sites. Very fast exchange, on the microsecond time scale, was observed for the Li hopping processes. Activation energies are determined and correlated to structural properties including interatomic Li distances and Li-O bottleneck sizes.

6.
Kennedy Inst Ethics J ; 11(3): 221-38, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11700680

RESUMEN

The commercialization of biotechnology, especially research and development by transnational pharmaceutical companies, is already excessive and is increasingly dangerous to distributive justice, human rights, and access of marginal populations to basic human goods. Focusing on gene patenting, this article employs the work of Margaret Jane Radin and others to argue that gene patenting ought to be more highly regulated and that it ought to be regulated with international participation and in view of concerns about solidarity and the common good. The mode of argument called for on this issue is more pragmatic than logical, emphasizing persuasion based on evidence about the reality and effects of control of genetic research by profit-driven biotech companies.


Asunto(s)
Biotecnología , Comercio , Mercantilización , Investigación Genética , Genética , Internacionalidad , Patentes como Asunto , Justicia Social , Catolicismo , Países en Desarrollo , Industria Farmacéutica , Genoma Humano , Humanos , Plantas Modificadas Genéticamente , Sujetos de Investigación , Valores Sociales
7.
J Relig Ethics ; 29(1): 25-33, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11837289

RESUMEN

In response to Gilbert Meilaender's innovative interpretation of Augustine and of Roman Catholic teaching, the author suggests (1) that Meilaender attributes to Augustine a more positive view of sexual pleasure than the texts will support, (2) that modern Roman Catholic teaching suggests that love should have priority over procreation as a meaning of sex; and (3) that the moral logic of Meilaender's argument does not require a rejection of all reproductive technologies. Nonetheless, the author agrees that a more critical attitude should be adopted toward the reasons for which technologically assisted reproduction is promoted and undertaken, as well as toward its social impact.


Asunto(s)
Catolicismo , Técnicas Reproductivas Asistidas , Sexualidad , Humanos
9.
Womens Health Issues ; 10(3): 131-5, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10828549

RESUMEN

United States debates over stem cell research too often take the status of the embryo as the only decisive ethical issue, assume that if the embryo cannot be shown to be a person its destruction for a good cause is justified, and are insufficiently critical of economic incentives to legitimate and fund such research. Even if stem cell research ought not be banned, it could be situated and controlled on a spectrum of other health care needs through limited funding policies; aggressive peer review; regulatory and legal oversight applying to all research, however funded; and stringent patenting criteria.


Asunto(s)
Biotecnología/economía , Embrión de Mamíferos , Ética Médica , Investigación , Células Madre , Política de Salud , Humanos , Principios Morales , Apoyo a la Investigación como Asunto/legislación & jurisprudencia , Estados Unidos
14.
Hofstra Law Rev ; 27(3): 487-501, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-12650145

RESUMEN

This Essay addresses the negative impact of human cloning on the family, and argues further that market incentives to develop and implement cloning techniques exploit and exacerbate socioeconomic inequities. It suggests that cloning should be prohibited internationally and examines possible routes to that aim. To begin with, it offers some reflections on the nature of moral argument, and on the role of religion in public debate.


Asunto(s)
Clonación de Organismos/ética , Relaciones Familiares , Niño , Clonación de Organismos/economía , Mercantilización , ADN , Femenino , Financiación Gubernamental , Humanos , Masculino , Religión , Técnicas Reproductivas Asistidas , Padres Solteros , Justicia Social
19.
J Med Philos ; 14(5): 497-522, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2691613

RESUMEN

The Vatican Instruction on reproductive technologies and the OTA report, Infertility, both use "rights" language to advance quite different views of the same subject matter. The former focuses on the rights and welfare of the embryo, and the protection of the family, while the latter stresses the freedom and rights of couples. This essay uses the work of Alasdair MacIntyre and Jeffrey Stout to consider the different traditions grounding these definitions of rights. It is proposed that a potentially effective mediating language could be that of "human nature", and argued that donor methods raise more serious moral objections than homologous ones.


Asunto(s)
Diversidad Cultural , Análisis Ético , Ética , Lenguaje , Principios Morales , Técnicas Reproductivas , Catolicismo , Teoría Ética , Ética Médica , Regulación Gubernamental , Humanos , Obligaciones Morales , Donación de Oocito , Autonomía Personal , Justicia Social , Espermatozoides , Estados Unidos , United States Office of Technology Assessment , Valor de la Vida , Derechos de la Mujer/legislación & jurisprudencia
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