The enigmatic fetal subplate compartment forms an early tangential cortical nexus and provides the framework for construction of cortical connectivity.

Atlas of clinical gross anatomy

Prior studies have identified two anatomically and neurochemically distinct cellular compartments within the mammalian striatum, termed striosomes and matrix, which express μ-opioid receptors (μOR) and EphA4, respectively. Here we identify and characterize an additional compartment in the rat striatum composed of neurons that express EphA7. In situ hybridization and immunohistochemical data indicate that neurons expressing EphA7 mRNA and protein are arranged in a banded "matrisome-like" pattern confined to the matrix in the dorsal striatum. Within the ventral striatum, EphA7-positive (+) neurons have a less organized mosaic pattern that partially overlaps areas expressing μOR. Immunolabeling data demonstrate that EphA7+ striatofugal axons form distinct fascicles leaving the striatum. Within the globus pallidus, EphA7+ axons terminate primarily within ventromedial areas of the nucleus and along its striatal border. EphA7+ axons avoid regions containing dopamine neurons within the substantia nigra and preferentially innervate areas near the rostral and caudal margins of the nucleus. Within both nuclei, EphA7+ axons have similar but more restricted terminal fields than the entire population of EphA4+ matrix axons, indicating that EphA7+ axons comprise a subpopulation of matrix axons. Ligand binding data demonstrate that ephrin-A5 selectively binds areas of the striatum, globus pallidus, and substantia nigra containing EphA7+ neurons and axons, but not areas expressing only EphA4. Our findings demonstrate that EphA7 expression identifies a novel "matrisome" compartment within the matrix that binds ephrin-A5 and possesses unique axonal projections. Our findings also suggest that EphA7 and ephrin-A5 may participate in the formation of this matrisome subcompartment and its striatofugal projections.

EphA7 expression identifies a unique neuronal compartment in the rat striatum.

We present a project that focused on creating a wearable medical device that uses photoplethysmography and pulse oximetry technology. The pulse oximeter sensor holder was designed to be mounted on the chest using adhesive tape and a threaded holder that the cover turns into to increase pressure on the sensor. Our holder can apply a pressure range of 0-51 mmHg. The range for greatest PPG amplitudes from the chest is 10-30 mmHg. The reflectance type pulse oximeter housed in the holder was able to read pulse rate to within approximately ±1.35 BPM compared to the EKG heart rate signal. Industry standards for finger pulse oximeters read pulse rate with ±3 BPM accuracy. The device was not tested for oxygen saturation due to time constraints and IRB approved testing.

A Reflectance Sensor Holder for PPG Measurements from the Chest

Background Emerging evidence suggests older adults may experience subtle hemothoraces that progress over several days. Delayed progression and delayed development of traumatic hemothorax (dHTX) have not been well characterized. We hypothesized dHTX would be infrequent but associated with factors that may aid prediction. Methods We retrospectively reviewed adults aged ≥50 years diagnosed with dHTX after rib fractures at two level 1 trauma centers (March 2018 to September 2019). dHTX was defined as HTX discovered ≥48 hours after admission chest CT showed either no or ‘minimal/trace’ HTX. Two blinded, board-certified radiologists reviewed inpatient chest imaging and classified injury patterns according to Chest Wall Injury Society (CWIS) taxonomy. Descriptive analysis was performed for demographic and hospitalization characteristics. Results We identified 14 patients with pooled dHTX rate of 1.3%. After initial chest CT negative for concerning hemothoraces, the patients did not undergo follow-up imaging until new symptoms (shortness of breath, chest pain) developed: eight (57%) were not diagnosed until after discharge from initial hospitalization (mean (range): 9 (2–20) days after discharge). Aspirin and/or anticoagulants were involved in fewer than half of cases (43%). According to CWIS taxonomy, all patients had a series of posterolateral fractures with at least one offset or displaced fracture, and an average of six consecutive rib fractures. All patients underwent tube thoracostomy and six patients (42%)—all aged Discussion Preliminary data suggest older adults with rib fractures may be at risk of experiencing delayed progression of trace hemothoraces or a delayed presentation of hemothoraces. Asymptomatic progression or readmission to other services/hospitals likely occurs and true dHTX rates are likely higher. Our preliminary findings suggest a possible anatomic explanation for severe chest wall injury patterns’ association with dHTX. Further characterization and capturing the true incidence of dHTX first requires wider recognition of this complication.

https://tsaco.bmj.com/content/tsaco/6/1/e000626.full.pdf

Complication to consider: delayed traumatic hemothorax in older adults.

At present, there have not been any detailed studies examining the size relationships of the intercostal arteries. This study was carried out to investigate the relationship between the vessel lumenal diameter of ipsilateral, paired anterior and posterior IC arteries, as well as with the length of the IC space supplied by each artery. Samples were collected from the second-sixth anterior and posterior IC arteries near their site of origin, and the lengths of the corresponding IC spaces were measured in 42 cadavers. Lumenal diameters of both the anterior and posterior IC arteries at consecutive IC space closely followed second degree polynomial regression models (R2 = 0.9655, and R2 = 0.9741, respectively), and reached maximum size at the fifth IC space, which was found to be the longest of the IC spaces. No direct relationship was observed between diameters of the paired anterior and posterior IC arteries, although there was a trend for the larger anterior IC arteries to be paired with the larger posterior IC arteries. The calculated rate of blood flow at each IC artery was approximately two-fold greater in males than in females. These results suggest that the length of the IC space, and hence the extent of the thoracic wall supplied, is a major factor in determining the diameter of both anterior and posterior IC arteries. Since COPD is such a prevalent disease, this study also examined its influence on the IC arteries, and found that the posterior IC arteries are significantly larger among afflicted subjects. Clin. Anat. 28:219–226, 2015. © 2014 Wiley Periodicals, Inc.

Factors influencing the diameter of human anterior and posterior intercostal arteries.

Several Eph receptors, prominently EphA4 and EphA7, and their corresponding ligands are known to influence neocortical development, including topographic sorting of thalamocortical axons within primary somatosensory cortex (SI). This study investigated postnatal expression of a ligand that can bind to these receptors, ephrin-A2. Quantitative methods revealed that expression of ephrin-A2 mRNA in SI reached maximum levels on postnatal day (P) 4 and dropped thereafter to background by P18. Ephrin-A2 mRNA expression assessed by in situ hybridization qualitatively revealed a similar time course and localized the expression pattern primarily in two broad laminae in SI, comprising the supragranular and infragranular layers, and with additional expression in the subplate. This expression pattern was investigated in greater detail using immunohistochemistry for ephrin-A2 protein. Immunoreactivity generally showed the same laminar distribution as seen with in situ hybridization, except that it persisted longer, lasting to approximately P14. Expression in the cortical plate was low or absent within presumptive layer IV, and it remained so as cortical lamination progressed. Double-labeling immunohistochemistry with confocal microscopy revealed that cortical neurons were the principal elements expressing ephrin-A2 protein. These findings are consistent with possible involvement of ephrin-A2, in concert with one or more Eph receptors, in influencing arbor development of thalamocortical axons at cortical layer IV boundaries.

https://anatomypubs.onlinelibrary.wiley.com/doi/pdf/10.1002/ar.21485

Laminar expression of ephrin-A2 in primary somatosensory cortex of postnatal rats.

Cortex?Circuits Within the Somatosensory Neonatal Forelimb Amputation Influence Development Does Reorganization in the Cuneate Nucleus Following

Influence Development of Anomalous Circuits Within the Somatosensory Cortex? Does Reorganization in the Cuneate Nucleus Following Neonatal Forelimb Amputation

Richard D. Lane

Papers

Factors influencing the diameter of human anterior and posterior intercostal arteries.

Laminar expression of ephrin-A2 in primary somatosensory cortex of postnatal rats.

Cortex?Circuits Within the Somatosensory Neonatal Forelimb Amputation Influence Development Does Reorganization in the Cuneate Nucleus Following

Influence Development of Anomalous Circuits Within the Somatosensory Cortex? Does Reorganization in the Cuneate Nucleus Following Neonatal Forelimb Amputation