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Plant-parasitic nematodes conduct a series of sophisticated behaviors to complete their life cycles. Among these, locomotion behaviors, including finding the host and migrating to the feeding site, directly affect the success of parasitism. Thus, disrupting locomotion behaviors has the potential to control these parasites. γ-Aminobutyric acid (GABA) is the prominent inhibitory neurotransmitter in nematodes. GABA-immunoreactive neurons are mostly found in motor neurons, where they regulate behaviors in the model nematode C. elegans. However, the GABA system in most stylet-bearing nematodes has received little attention. Using immunohistochemistry, we found variation in the pattern of GABA-immunoreactivity among two major plant-parasites and a fungal feeder. Some of these GABA-immunoreactive neurons lack clear homologs to C. elegans. Pharmaceutical assays showed that applying GABA, its agonist, and its antagonist, can disrupt the locomotion behaviors of these nematodes, although sensitivity to a given compound varied between species. Our data suggest that the GABA system is a potential target for the control of plant-parasitic nematodes.

Assigning behavioral functions to neural structures has long been a central goal in neuroscience and is a necessary first step toward a circuit-level understanding of how the brain generates behavior. Here, we map the neural substrates of locomotion and social behaviors for Drosophila melanogaster using automated machine-vision and machine-learning techniques. From videos of 400,000 flies, we quantified the behavioral effects of activating 2,204 genetically targeted populations of neurons. We combined a novel quantification of anatomy with our behavioral analysis to create brain-behavior correlation maps, which are shared as browsable web pages and interactive software. Based on these maps, we generated hypotheses of regions of the brain causally related to sensory processing, locomotor control, courtship, aggression, and sleep. Our maps directly specify genetic tools to target these regions, which we used to identify a small population of neurons with a role in the control of walking.

Background: Injuries of the acromioclavicular joint (ACJ) are common shoulder injuries that often lead to pain and dysfunction of the affected shoulder. Regardless of operative or nonoperative treatment, a relatively large number of patients remain symptomatic and experience pain. However, the specific source of persistent pain in the ACJ remains ambiguous. Purpose: To investigate the presence of sensory nerve fibers or pain-generating neurotransmitters within the intra-articular disk of the ACJ to determine its potential role as an independent pain generator in ACJ disorders. Study Design: Descriptive laboratory study. Methods: Twelve paired ACJs from 6 fresh human cadavers (mean age, 56 years; range, 41-82 years) were harvested and freed from surrounding soft tissues, leaving only the ACJ capsule intact. The specimens were placed in 4.5% formaldehyde fixative for a minimum of 48 hours. Coronal plane sections were obtained and demineralized in EDTA for a week, embedded in paraffin for 12 hours, and dehydrated overnight. With a rotation microtome, 2-μm sections were cut and stained with hematoxylin and eosin to investigate tissue architecture and confirm the presence of a fibrocartilaginous intra-articular disk. The sections were immunohistochemically stained with antisera against S100, neuropeptide Y (NPY), and substance P (SP) to detect for neural tissue. Additionally, a nerve fiber count per 10 high-power fields representing an area of 0.2 mm2 was conducted for S100 stains. All sections were examined for the presence of positive immunoreactivity to S100, NPY, and SP. Results: The presence of a fibrocartilaginous intra-articular disk could be observed in all 12 examined ACJs. In all specimens, an immunoreactivity to S100, NPY, and SP could be observed within the superior peripheral region of the intra-articular disk. High-power field nerve counts of the S100 stains revealed a mean ± SD of 7.9 ± 2.28 nerves per 10 high-power fields (range, 4-12). Conclusion: The documented immunoreactivity to S100, NPY, and SP indicates the presence of somatic and autonomic nerve fibers within the intra-articular disk of the ACJ. Clinical Relevance: Confirming the presence of nerve fibers within the intra-articular disk of the ACJ suggests that the disk itself could be an independent source of pain after injury and thus a possible explanation for recalcitrant pain after treatment. [ABSTRACT FROM AUTHOR]

Study Design: Experimental in-vivo animal study.Objective: The aim of this study was to evaluate an Artificial Intelligence (AI)-enabled ultrasound imaging system's ability to detect, segment, classify, and display neural and other structures during trans-psoas spine surgery.Summary Of Background Data: Current methodologies for intraoperatively localizing and visualizing neural structures within the psoas are limited and can impact the safety of lateral lumbar interbody fusion (LLIF). Ultrasound technology, enhanced with AI-derived neural detection algorithms, could prove useful for this task.Methods: The study was conducted using an in vivo porcine model (50 subjects). Image processing and machine learning algorithms were developed to detect neural and other anatomic structures within and adjacent to the psoas muscle while using an ultrasound imaging system during lateral lumbar spine surgery (SonoVision,™ Tissue Differentiation Intelligence, USA). The imaging system's ability to detect and classify the anatomic structures was assessed with subsequent tissue dissection. Dice coefficients were calculated to quantify the performance of the image segmentation.Results: The AI-trained ultrasound system detected, segmented, classified, and displayed nerve, psoas muscle, and vertebral body surface with high sensitivity and specificity. The mean Dice coefficient score for each tissue type was >80%, indicating that the detected region and ground truth were >80% similar to each other. The mean specificity of nerve detection was 92%; for bone and muscle, it was >95%. The accuracy of nerve detection was >95%.Conclusion: This study demonstrates that a combination of AI-derived image processing and machine learning algorithms can be developed to enable real-time ultrasonic detection, segmentation, classification, and display of critical anatomic structures, including neural tissue, during spine surgery. AI-enhanced ultrasound imaging can provide a visual map of important anatomy in and adjacent to the psoas, thereby providing the surgeon with critical information intended to increase the safety of LLIF surgery.Level of Evidence: N/A. [ABSTRACT FROM AUTHOR]

Introduction: In this study we provide detailed quantification of upper extremity nerve and fascicular anatomy. The purpose is to provide values and trends in neural features useful for clinical applications and neural interface device design.Methods: Nerve cross-sections were taken from 4 ulnar, 4 median, and 3 radial nerves from 5 arms of 3 human cadavers. Quantified nerve features included cross-sectional area, minor diameter, and major diameter. Fascicular features analyzed included count, perimeter, area, and position.Results: Mean fascicular diameters were 0.57 ± 0.39, 0.6 ± 0.3, 0.5 ± 0.26 mm in the upper arm and 0.38 ± 0.18, 0.47 ± 0.18, 0.4 ± 0.27 mm in the forearm of ulnar, median, and radial nerves, respectively. Mean fascicular diameters were inversely proportional to fascicle count.Conclusion: Detailed quantitative anatomy of upper extremity nerves is a resource for design of neural electrodes, guidance in extraneural procedures, and improved neurosurgical planning. Muscle Nerve 56: 463-471, 2017. [ABSTRACT FROM AUTHOR]

Quantitative methods for assessing neural anatomy have rapidly evolved in neuroscience and provide important insights into brain health and function. However, as new techniques develop, it is not always clear when and how each may be used to answer specific scientific questions posed. Dendritic spines, which are often indicative of synapse formation and neural plasticity, have been implicated across many brain regions in neurodevelopmental disorders as a marker for neural changes reflecting neural dysfunction or alterations. In this Perspective we highlight several techniques for staining, imaging, and quantifying dendritic spines as well as provide a framework for avoiding potential issues related to pseudoreplication. This framework illustrates how others may apply the most rigorous approaches. We consider the cost-benefit analysis of the varied techniques, recognizing that the most sophisticated equipment may not always be necessary for answering some research questions. Together, we hope this piece will help researchers determine the best strategy toward using the ever-growing number of techniques available to determine neural changes underlying dendritic spine morphology in health and neurodevelopmental disorders.

The anterolateral thigh (ALT) flap is one of the commonly used sensate flaps for intra-oral, hand, and foot reconstruction. The objective of this study was to describe the anatomic location of the sensory nerves supplying the ALT flap in relation to the surface landmarks and with the vascular pedicles. The dissections were carried out in 28 embalmed specimens. An axial line from the anterior superior iliac spine to the superolateral border of the patella and two circles with radii of 5 and 10 cm centered on the midpoint of the former line were used for the surface landmarks. At the intersection point of the axial line and the 10-cm circle, the main lateral femoral cutaneous nerve (LFCN) and its anterior branch were located within 1 and 2.4 cm, respectively. At the intersection point of the axial line and the 5-cm circle, the anterior branch of the LFCN was located within 2.8 cm. The anterior branch of the LFCN can be detected within 3 cm from the central perforator pedicle in all specimens. The posterior branch of the LFCN, superior perforator nerve, and median perforator nerve were found in more variable locations. The findings from our study provide additional information for clinical use in the planning of sensate ALT flap harvest. [ABSTRACT FROM AUTHOR]

The DaVinci Robot (Intuitive Surgical, Sunnyvale California) with its magnified 3-D vision and multi-jointed wristed instruments enabled us to perform radical prostatectomy with consideration for the pelvic anatomy. In the present paper, we review the pelvic autonomic neuroanatomy with respect to robotic prostatectomy and demonstrate the procedures and critical points of nerve-sparing robotic radical prostatectomy based on novel anatomic concepts. Microscopic and macroscopic data were acquired from 30 fresh and 25 fixed male cadavers. A video study of 205 surgeries was performed for establishing the anatomy relevant to robotic prostatectomy. From a practical standpoint, we could group the relevant neural tissue into three broad zones: (1) proximal neurovascular plate (PNP), (2) predominant neurovascular bundles (PNB), (3) accessory distal neural pathways (ANP). Autonomic ganglion cells existed widely not only in nerve components but also along the viscera. The critical areas of nerve sparing surgery were the distal end of PNP, the entire PNB, and the circumference of the apex. Interindividual differences of cell counts were evident in all sites. Based on these concepts, we established the Athermal Robotic Technique (ART) for nerve sparing prostatectomy. Surgical and oncological outcomes were not mature but feasible. These tri-zonal and ganglion cell concepts may be of benefit to new surgeons undertaking nerve-sparing robotic radical prostatectomy. [ABSTRACT FROM AUTHOR]