Women's Perspectives of Needs Surrounding Adverse Birth Outcomes: A Qualitative Assessment of the Neighborhood Impact of Adverse Birth Outcomes.

Objectives African Americans are two times more likely to suffer adverse birth outcomes (i.e., low birth weight, preterm birth, and infant mortality) when compared to all other ethnic groups and this pattern is no different for Douglas County, Nebraska, where the majority of African Americans in Nebraska reside. Our goal was to identify factors, as described by local women, that contribute to adverse birth outcomes in the predominantly African American community of Northeast Douglas County in Omaha, NE, to ensure that these women's voices were included in the development of interventions to improve their neighborhood's birth outcomes. The paper describes the results of a qualitative needs assessment of these women which will aid in the design and implementation of neighborhood-based solutions. Methods We brought together a group of women with varying levels of birthing experience, time spent living in the neighborhood, and overall community involvement. Individual in-depth, in person, and telephone interviews were used to collect participants' perceptions of birth outcomes, neighborhood resources for pregnant women, and neighborhood strengths and weaknesses. Results The needs assessment identified that, although women in this neighborhood have experience with adverse birth outcomes, these experiences are not discussed resulting in a lack of awareness of the wide spread racial disparities in birth outcomes and the efforts and resources to address this public health problem. Conclusions for Practice This study reveals the power of direct conversations with women impacted by adverse birth outcomes, as they must be primary partners in any efforts to improve birth outcomes.

NMDA receptor NR1 and NR2A/B subunit expression in trigeminal neurons during early postnatal development.

Trigeminal motoneurons (Mo5), mesencephalic trigeminal neurons (Me5), and supratrigeminal (Su5) and intertrigeminal (15) neurons are important constituents of the neural circuitry responsible for jaw movements observed during ingestive behaviors. In addition, in adult animals, N-methyl-D-aspartate (NMDA) receptors are a critical component of the brainstem circuitry responsible for reflex- and centrally activated jaw movements. However, little is known about the expression of this receptor in circuitry used to produce neonatal jaw movements. Receptor immunohistochemistry was used to describe changes in the expression of NMDA NR1 and NR2A/B receptor subunits in Mo5, Me5, Su5, and I5 neurons during postnatal development. Rats at postnatal days (P) 1, 3, 8, 15-16, 21-24, and 28-35 were used. An affinity-purified polyclonal antibody against the NR1 subunit and an affinity-purified polyclonal antibody that recognizes both NR2A and 2B subunits were used to depict the expression of these subunits. In Mo5, immunoreactivity was noted for both antibodies throughout the time frame sampled. NR1 expression in Me5 neurons emerged at P1. NR2A/B expression emerged at P3 in caudal and middle regions of Me5 and at P8 for rostral regions of the nucleus. NR1 immunoreactivity was present at P1 for neurons in I5 and at P3 for neurons in the Su5 region. NR2A/B subunit expression in Su5 and 15 neurons emerged at P8. These results provide evidence for NMDA receptor subunits in neonatal trigeminal neurons used in oral-motor circuitry and suggest a role for the NMDA receptor in synaptogenesis associated with these neurons during postnatal development.

AMPA receptor subunit expression in trigeminal neurons during postnatal development.

Trigeminal motoneurons (Mo5) and mesencephalic trigeminal neurons (Me5) are important constituents of the neural circuitry responsible for jaw movements. Non-N-methyl-D-aspartate (NMDA) glutamate receptors are a critical component of the brainstem circuitry responsible for reflex and centrally activated jaw movements; however, little is known about the expression of these receptors in neonatal oral-motor circuitry. Receptor immunohistochemistry using affinity-purified polyclonal antibodies directed against GluR1, GluR2/3/4c, and GluR4, respectively, and a monoclonal antibody directed against the GluR2 subunit, were used in rats at postnatal day (P)1, P3, P5, P10, P19-21, P32-35, and P60 to describe the expression of the alpha-amino-d-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor in Mo5 and Me5 neurons. In Mo5, immunoreactivity was noted for all antibodies throughout the time frame sampled. Neurons in caudal portions of Me5 displayed immunoreactivity to each antibody except at P60 when GluR2 immunoreactivity was absent. Neurons located in rostral Me5 displayed GluR2/3/4c and GluR4 immunoreactivity throughout the time frame, GluR1 immunoreactivity emerged at P3 and a transient expression of GluR2 expression was observed between P10 and P32-35. The lack of labeling of some neurons in both regions, coupled with differences in temporal expression, suggests that there are differences in the AMPA receptor phenotype within and between Mo5 and Me5 during postnatal development. Differences in AMPA subunit composition suggest a complex role for AMPA-mediated glutamatergic neurotransmission in brainstem circuits controlling jaw movements.

Immunohistochemical localization of glutamate and glutaminase in guinea pig trigeminal premotoneurons.

Previous electrophysiological experiments in guinea pigs from our laboratory [11,36,37] have suggested that synaptic transmission between last-order interneurons (premotoneurons) and trigeminal motoneurons during reflex activation or cortically induced rhythmical jaw movements is mediated by excitatory amino acids (EAAs). In the present study, we performed a series of double-labeling experiments in guinea pigs to determine the location of neurons which contain glutamate or glutaminase and project to the trigeminal motor nucleus (Mo5). This was accomplished by combining immunohistochemical staining and standard retrograde tract-tracing techniques. Injections of a retrograde tracer, colloidal-gold bound to inactivated WGA-HRP (gWGA-HRP), into the trigeminal motor nucleus labeled a column of neurons originating adjacent to Mo5, including the supratrigeminal nucleus, intertrigeminal nucleus and the mesencephalic nucleus of V. The column extended caudally into the parvocellular reticular formation and adjacent trigeminal sensory nucleus oralis and oralis gamma subdivision. In all of these regions, immunoreactivity to glutamate or glutaminase was observed co-localized with gWGA-HRP.

GABA(A) receptor beta2/beta3 subunit and GAD67 immunoreactivity in the trigeminal motor nucleus during early postnatal development.

GABA neurotransmission plays a role in brainstem circuitry responsible for jaw movements. We investigated the developmental relationship between terminals expressing GAD67 and GABA(A) receptor beta(2)/beta(3) subunit expression within the trigeminal motor nucleus. GAD67 immunoreactivity was intense throughout development. Neuropilar beta(2)/beta(3) immunoreactivity emerged during the 2nd postnatal week. Our data provide anatomical evidence for a GABAergic innervation of neonatal trigeminal motoneurons and suggest that beta(2)/beta(3) subunit expression is developmentally regulated in trigeminal motoneurons.

The Krox-20 null mutation differentially affects the development of masticatory muscles.

The Krox-20 null mutation results in a loss of rhombomeres 3 and 5, which give rise to neurons that are essential to oral motor behaviors. Thus, the Krox-20 null mutant is an excellent model to investigate the development of oral motor circuitry. Our morphological examination of embryonic and neonatal Krox-20 null mutants revealed that a significant reduction of anterior digastric and mylohyoid muscles, the primary jaw openers, occurs between embryonic days 15 and 19. There are no gross morphological alterations in other masticatory muscles. These findings demonstrate that Krox-20 expression is critical for the normal development of the primary jaw opener musculature and they help explain previous studies documenting a reduction in jaw opening in Krox-20 null mutants. Since jaw opening is the power stroke of suckling behavior, our data help explain the reduction of colostrum/milk ingestion in Krox-20 null mutant neonates.

Expression of group I and II metabotropic glutamate receptors in trigeminal neurons during postnatal development.

Trigeminal motoneurons (Mo5), mesencephalic trigeminal neurons (Me5), supratrigeminal neurons (Su5), and intertrigeminal neurons (I5) are important constituents of the neural circuitry responsible for jaw movements. Glutamate neurotransmission, mediated by ionotropic and metabotropic glutamate receptors (mGluRs), is critical for the production of jaw movements. To better understand the role of mGluR-mediated modulation of these neurons during early postnatal development, we conducted a series of experiments to illustrate the ontogeny of mGluRs 1, 5 (group I) and mGluRs 2, 3 (group II) in Mo5, Me5, Su5, and I5 neurons using receptor immunohistochemistry. Results demonstrate that the temporal expression of mGluRs is differentially regulated between, and within these trigeminal nuclei. The localization of group I and II mGluRs in these nuclei suggests a role for these receptors in mediating glutamatergic neurotransmission in brainstem circuits responsible for oral-motor behaviors.