Coordination of the axonal cytoskeleton during the emergence of axon collateral branches

The formation of branches during development allows a single axon to make synaptic contacts with numerous target neurons,often in different parts of the nervous system,thereby allowing for the establishment of complex patterns of neuronal connectivity.

Localized regulation of the axon shaft during the emergence of collateral branches

The ability of the axon to form de novo collateral branches along its length is fundamental to the establishment of complex patterns of connectivity during development and is also a major response of many axonal populations following injury.The emergence of branches is under both positive and negative control by extracellular signals.

Acute celiac artery occlusion secondary to blunt trauma:Two case reports

BACKGROUND Acute celiac artery(CA)injuries are extremely rare but potentially life-threatening and are more often caused by a penetrating injury rather than a blunt injury.The clinical manifestation of CA injuries is usually atypical,which easily causes missed diagnosis and misdiagnosis.Currently,there are only a few reports of acute traumatic occlusion of CA.The CA artery gives off branches to dominate the liver,stomach.and spleen;however,occluded CA did not cause significant organ ischemia,and the compensatory blood flow from the superior mesenteric artery(SMA)played a pivotal role.CASE SUMMARY Herein,we report two cases of acute CA occlusion secondary to severe blunt trauma.Case one was a 19-year-old male,suffered from a motorcycle crash.He complained of dyspnea,and the closed drainage was performed soon after the hemopneumothorax was confirmed by ultrasound.Computed tomography(CT)scan revealed hemopneumothorax,multiple rib fractures,right scapular fracture,and liver rupture.Reexamination with contrast-enhanced CT suggested perihepatic fluid was significantly increased,and CA was occluded.Because the hepatic hemorrhage is associated with hepatic artery injury,the CA was retrogradely opened through the SMA,and then,the right hepatic artery was embolized with coils successfully through the conventional pathway.Stent implantation was not performed,and the CA occlusion was managed by conservative treatment.A follow-up CT scan 3 mo after discharge showed the origin of CA remained occluded.Case two was a 37-year-old man,suffered injury from fall from height.He complained of lower back and bilateral heel pain.Contrast-enhanced CT examination revealed multiple rib fractures,bilateral pneumothorax,fourth lumbar(L4)vertebral burst fracture,and pelvic fractures.Furthermore,a small high-density mass in a lesser peritoneal sac and in front of the abdominal aorta was detected.The reexamination 14 h after admission showed the CA was occluded.The patient was conservatively treated.The symptoms of nausea after meals disappeared about 4 wk later,and abdominal distension was significantly relieved after 6 wk.The abdominal CT angiography at 60 d showed that the CA thrombus was not recanalized.CONCLUSION Patients with CA occlusion will have different clinical manifestations,and the dominant organ will not have obvious ischemia.Conservative treatment is safe,and the patient’s symptoms will be improved with the establishment of collateral circulation.

Flow dynamics analyses of pathophysiological liver lobules using porous media theory

Blood flow inside the liver plays a key role in hepatic functions, and abnormal hemodynamics are highly correlated with liver diseases. To date, the flow field in an elementary building block of the organ, the liver lobule,is difficult to determine experimentally in humans due to its complicated structure, with radially branched microvasculature and the technical difficulties that derive from its geometric constraints. Here we established a set of 3D computational models for a liver lobule using porous media theory and analyzed its flow dynamics in normal, fibrotic,and cirrhotic lobules. Our simulations indicated that those approximations of ordinary flow in portal tracts（PTs） and the central vein, and of porous media flow in the sinusoidal network, were reasonable only for normal or fibrotic lobules.Models modified with high resistance in PTs and collateral vessels inside sinusoids were able to describe the flow features in cirrhotic lobules. Pressures, average velocities, and volume flow rates were profiled and the predictions compared well with experimental data. This study furthered our understanding of the flow dynamics features of liver lobules and the differences among normal, fibrotic, and cirrhotic lobules.

Can we be aware of both visceral and somatic sensations via a single neuronal pathway?

Sensory information arising from somatic and visceral area is thought to be respectively transmitted to the brain by two distinct sensory neuronal systems, the somatic and visceral sensory pathway. A novel and unique spinal sensory system, the spinosolitary tract-dorsal column postsynaptic neuronal system (SST-DCPS), was physiologically and anatomically identified. The spinal neurons project to both visceral (the solitary tract nucleus) and somatic sensory (the dorsal column nuclei) nuclei via their branched axons and receive both visceral and somatic sensory information ascending from periphery through dichotomized primary afferents and descending from their targets via their branched axons. The brain might thus be aware of both visceral and somatic sensation via a single SST-DCPS neuronal channel. The finding of SST-DCPS system, as an example, might be considered as an intersection or fuzzy set of the SST and DCPS system and the concept of dichotomy in classification of neurons and neuronal pathways