Head-tail-head neural wiring underlies gut fat storage in Caenorhabditis elegans temperature acclimation.

Animals maintain the ability to survive and reproduce by acclimating to environmental temperatures. We showed here that Caenorhabditis elegans exhibited temperature acclimation plasticity, which was regulated by a head-tail-head neural circuitry coupled with gut fat storage. After experiencing cold, C. elegans individuals memorized the experience and were prepared against subsequent cold stimuli. The cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB) regulated temperature acclimation in the ASJ thermosensory neurons and RMG head interneurons, where it modulated ASJ thermosensitivity in response to past cultivation temperature. The PVQ tail interneurons mediated the communication between ASJ and RMG via glutamatergic signaling. Temperature acclimation occurred via gut fat storage regulation by the triglyceride lipase ATGL-1, which was activated by a neuropeptide, FLP-7, downstream of CREB. Thus, a head-tail-head neural circuit coordinated with gut fat influenced experience-dependent temperature acclimation.

Critical Review and Consensus Statement for Neural Monitoring in Otolaryngologic Head, Neck, and Endocrine Surgery.

BACKGROUND: Enhancing patient outcomes in an array of surgical procedures in the head and neck requires the maintenance of complex regional functions through the protection of cranial nerve integrity. This review and consensus statement cover the scope of cranial nerve monitoring of all cranial nerves that are of practical importance in head, neck, and endocrine surgery except for cranial nerves VII and VIII within the temporal bone. Complete and applied understanding of neurophysiologic principles facilitates the surgeon's ability to monitor the at-risk nerve. METHODS: The American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) identified the need for a consensus statement on cranial nerve monitoring. An AAO-HNS task force was created through soliciting experts on the subject. Relevant domains were identified, including residency education, neurophysiology, application, and various techniques for monitoring pertinent cranial nerves. A document was generated to incorporate and consolidate these domains. The panel used a modified Delphi method for consensus generation. RESULTS: Consensus was achieved in the domains of education needs and anesthesia considerations, as well as setup, troubleshooting, and documentation. Specific cranial nerve monitoring was evaluated and reached consensus for all cranial nerves in statement 4 with the exception of the spinal accessory nerve. Although the spinal accessory nerve's value can never be marginalized, the task force did not feel that the existing literature was as robust to support a recommendation of routine monitoring of this nerve. In contrast, there is robust supporting literature cited and consensus for routine monitoring in certain procedures, such as thyroid surgery, to optimize patient outcomes. CONCLUSIONS: The AAO-HNS Cranial Nerve Monitoring Task Force has provided a state-of-the-art review in neural monitoring in otolaryngologic head, neck, and endocrine surgery. The evidence-based review was complemented by consensus statements utilizing a modified Delphi method to prioritize key statements to enhance patient outcomes in an array of surgical procedures in the head and neck. A precise definition of what actually constitutes intraoperative nerve monitoring and its benefits have been provided.

Topography and morphology of the bovine cranial cervical ganglion and its branches / Topografía y morfología del ganglio cervical craneal bovino y sus ramos

A detailed submacroscopic anatomical study of the cranial cervical ganglion (CCG) and its branches with its adjoining structures was carried out by examining 14 halves of seven heads of Holstein cattle under a magnifying lens to provide comprehensive descriptions with color photographs of the location, relation to neighboring structures, morphometry, and morphology of CCG and its branches. Our results were compared with previously nerves including jugular nerve; internal and external carotid nerves extremely, obtained morphological data on CCG in other ungulates to clarify the detailed comparative anatomy of CCG among them. The morphology of CCG and its branches in bovine was significantly and tangibly different from that of in other reported ungulates, especially in the direction of the ventral and dorsal poles of CCG being caudodorsal and rostroventral respectively, being larger and slightly more rostral, covered laterally by the dorsal part of the stylohyoid bone and caudal stylopharyngeus muscle, close relation of CCG to the medial retropharyngeal lymph node, wider distributions of external carotid nerve and its plexus to the adjacent arteries and visceral structures, lacking a communicating branch with the cervical spinal nerve, although all typical branches including the jugular nerve, carotid sinus branch, internal and external carotid nerves, communicating branches to vagus, glossopharyngeal, hypoglossal, cranial laryngeal, pharyngeal branch of vagus nerves, and close relationship between CCG and the longus capitis muscle, vagus nerve, and internal carotid artery were almost consistently present among the ungulates. The site of origin and the number of the major nerves including jugular nerve, internal and external carotid nerves extremely differed among the ungulates.

Se realizó un estudio anatómico submi-croscópico detallado del ganglio cervical craneal (GCC) y sus ramos, con las estructuras adyacentes, mediante el examen de 14 hemicabezas, correspondientes a siete cabezas de ganado Holstein, bajo aumento, para proporcionar descripciones completas; además se tomaron fotografías a color de la ubicación, su relación con estructuras vecinas y la morfometría y morfología del GCC y sus ramos. Se compararon los resultados obtenidos relacionados con los nervios, incluyendo las arterias carótidas interna y externa; los datos morfológicos obtenidos del GCC de otros ungulados tal vez aclaren la anatomía comparativa detallada del GCC entre los ungulados. Encontramos diferencia significativas en la morfología del GCC y sus ramos en comparación con otros ungulados reportados en la literatura, particularmente en la dirección de los polos ventral y dorsal del GCC, siendo estos caudodorsal y rostroventral respectivamente, presentándose más grande y ligeramente más rostral, cubierto lateralmente por la parte dorsal del hueso estilohioídeo y el músculo estilofaríngeo caudal. Se evidenció una estrecha relación del GCC con los nodos linfáticos retrofaríngeos mediales, con distribuciones más amplias del nervio carotídeo interno y el plexo adyacente a las arterias y estructuras viscerales, careciendo de un ramo comunicante con el nervio espinal cervical. En todos los ungulados se encontraron consistentemente todos los ramos nerviosos típicos, incluyendo el nervio yugular, el ramo del seno carotídeo, los nervios carotídeos interno y externos, los ramos comunicantes para el nervio vago, glosofaríngeo, hipogloso, laringeo craneal, ramo faríngea del nervio vago, y la estrecha relación entre el GCC y el músculo largo de la cabeza, el nervio vago y la arteria carótida interna. Se determinaron diferencias importantes en el sitio y origen de la mayoría de los nervios, incluyendo el nervio yugular y los nervios carotídeos interno y externos.

Superficial Head and Neck Anatomy for Dermatologic Surgery: Critical Concepts.

BACKGROUND: Thorough understanding of head and neck anatomy is useful and necessary for dermatologic surgery. OBJECTIVE: To highlight pertinent head and neck anatomic structures that are encountered during dermatologic surgery and correlate these with common surgical problems. METHODS: Important anatomic structures and regional cutaneous anatomy are discussed and illustrated. RESULTS: Several important anatomic structures exist within the head and neck that can influence surgical outcomes. CONCLUSION: Anatomic knowledge is helpful to the dermatologic surgeon to optimize reconstructive outcomes.

Do cutaneous nerves cross the midline?

Standard cutaneous innervation maps show strict midline demarcation. Although authors of these maps accept variability of peripheral nerve distribution or occasionally even the midline overlap of cutaneous nerves, this concept seems to be neglected by many other anatomists. To support the statement that such transmedian overlap exists, we performed an extensive literature search and found ample evidence for all regions (head/neck, thorax/abdomen, back, perineum, and genitalia) that peripheral nerves cross the midline or communicate across the midline. This concept has substantial clinical implications, most notably in anesthesia and perineural tumor spread. This article serves as a springboard for future anatomical, clinical, and experimental research.

Motor nerves of the head and neck that are susceptible to damage during dermatological surgery.

As the incidence of non melanoma skin cancer rises, dermatologists will increasingly be called upon to perform excisions in the head and neck region. Damage to the motor nerves of the head and neck represents an important adverse event for patients, and a source of litigation for surgeons. Understanding the anatomy of this region is key to counselling patients about the possibility of motor nerve injury associated with particular skin surgical procedures. We describe the anatomy of the motor nerves of the head and neck that are most vulnerable to injury during dermatological surgery. The consequences of injury are outlined, and the surface anatomy and anatomical landmarks that may be used to identify the relevant danger zones are described.

True and 'choke' anastomoses between perforator angiosomes: part i. anatomical location.

BACKGROUND: Reports of more than two cutaneous perforator angiosome territories being raised successfully in distally based sural flaps are appearing in the literature. Previous anatomical studies have noted that cutaneous arteries, connected by true anastomosis without change in caliber, frequently parallel cutaneous nerves. METHODS: Twenty-four (48 sides) total body lead oxide cadaver injection studies, including seven arterial and two venous neurovascular, were examined, and the results were compared with clinical thermography in Part II. RESULTS: Long branches of cutaneous perforators, connected in a series by true anastomoses, paralleled at variable distances the main trunks of cutaneous nerves in the head, neck, torso, and upper and lower extremities. Specifically, in the leg, an average of 3.2 true anastomoses (range, 1 to 5) connected perforators that paralleled the sural nerve on the back of the calf; and 2.5 (range, 1 to 4) connected perforators on the medial side of the leg. These vascular freeways were paralleled by the short and long saphenous veins, respectively. CONCLUSIONS: True anastomoses frequently connect skin perforators that course in parallel with cutaneous nerves and veins. They provide an explanation for the long viable flaps noted in the leg, and it will be shown in Part II that they can be detected preoperatively with thermography.

Effective sensory modality activating an escape triggering neuron switches during early development in zebrafish.

Developing nervous systems grow to integrate sensory signals from different modalities and to respond through various behaviors. Here, we examined the development of escape behavior in zebrafish [45-170 h postfertilization (hpf)] to study how developing sensory inputs are integrated into sensorimotor circuits. Mature fish exhibit fast escape upon both auditory/vestibular (AV) and head-tactile stimuli. Newly hatched larvae, however, do not respond to AV stimuli before 75 hpf. Because AV-induced fast escape in mature fish is triggered by a pair of hindbrain neurons known as Mauthner (M) cells, we studied functional development of the M-cell circuit accounting for late acquisition of AV-induced escape. In fast escape elicited by head-directed water jet, minimum onset latency decreased throughout development (5 ms at 45-59 hpf, 3 ms after 75 hpf). After 75 hpf, lesioning the otic vesicle (OV) to eliminate AV input resulted in loss of short-latency (<5 ms) fast escape, whereas ablation of the sensory trigeminal ganglion (gV) to block head-tactile input did not. Before 75 hpf, however, fast escape persisted after OV lesion but disappeared after gV ablation. Laser ablation of the M-cell and Ca²âº imaging of the M-cell during escape demonstrated that M-cell firing is required to initiate short-latency fast escapes at every developmental stage and further suggest that head-tactile input activates the M-cell before 75 hpf, but that after this point AV input activates the M-cell instead. Thus, a switch in the effective sensory input to the M-cells mediates the acquisition of a novel modality for initiating fast escape.

Focused local anesthesia and analgesia for head and neck surgery.

Facility in the use of head and neck regional blocks will provide excellent perioperative analgesia and patient satisfaction. The scope of ambulatory surgical care for head and neck surgery will undoubtedly increase as expertize in these blocks expand in the face of strict criteria for patient selection. Supplemental sedation will be more precise with the intended result of less hangover and nausea and vomiting.

An inherited episodic head tremor syndrome in Doberman pinscher dogs.

Episodic head tremor anecdotally occurs in the Doberman pinscher dog breed, but it is not described in sufficient detail in the literature. We evaluated 87 Doberman pinschers affected with episodic head tremor and appropriate controls. The data analyzed were collected through detailed questionnaires, elaborate telephone interviews, and video recordings. Affected dogs underwent clinical, neurological, and laboratory examination, and a detailed diagnostic workup was conducted in 5 affected dogs. Pedigrees of affected dogs were collected and reviewed. The affected dogs expressed individual phenotypes of either horizontal or vertical head movements, but rarely did a dog exhibit head movements in both directions. There was considerable variation in duration (10 seconds to 3 hours; median: 3 minutes), frequency of occurrence (1-20 episodes/day; median: 2/day) of head tremor and length of the period without head tremor (1-1,800 days; median: 60 days). Subtle dystonic posturing of the head and neck during head tremor was evident on video recordings of 5 dogs. Certain exceptional conditions such as illness, surgery, some medications, heat, pseudopregnancy, or pregnancy triggered episodes. Two main important forms of episodic head tremor were identified: a familial early-onset form (age < 1 year) that affected littermates and a sporadic form. Affected dogs were traced back to 1 common sire, also including sporadic cases. Episodic head tremor is an inherited, paroxysmal movement disorder that affects the Doberman pinscher breed. Identification of the causative genes in the future will allow us to obtain a more detailed description of the syndrome.

Sensory systems in sawfishes. 2. The lateral line.

The lateral line system allows elasmobranchs to detect hydrodynamic movements in their close surroundings. We examined the distribution of pit organs and lateral line canals in 4 species of sawfish (Anoxypristis cuspidata, Pristis microdon, P. clavata and P. zijsron). Pit organs could only be located in A. cuspidata, which possesses elongated pits that are lined by dermal denticles. In all 4 pristid species, the lateral line canals are well developed and were separated into regions of pored and non-pored canals. In all species the tubules that extend from pored canals form extensive networks. In A. cuspidata, P. microdon and P. clavata, the lateral line canals on both the dorsal and ventral surfaces of the rostrum possess extensively branched and pored tubules. Based on this morphological observation, we hypothesized that these 3 species do not use their rostrum to search in the substrate for prey as previously assumed. Other batoids that possess lateral line canals adapted to perceive stimuli produced by infaunal prey possess non-pored lateral line canals, which also prevent the intrusion of substrate particles. However, this hypothesis remains to be tested behaviourally in pristids. Lateral line canals located between the mouth and the nostrils are non-pored in all 4 species of sawfish. Thus this region is hypothesized to perceive stimuli caused by direct contact with prey before ingestion. Lateral line canals that contain neuromasts are longest in P. microdon, but canals containing neuromasts along the rostrum are longest in A. cuspidata.

Electromyographic (EMG) neuromonitoring in otolaryngology-head and neck surgery.

Intraoperative neuromonitoring (IONM) is a relatively recent advance in electromyography (EMG) applied to otolaryngology-head and neck surgery. Its purpose is to allow real-time identification and functional assessment of vulnerable nerves during surgery. The nerves most often monitored in head and neck surgery are the motor branch of the facial nerve (VII), the recurrent or inferior laryngeal nerves (X), the vagus nerve (X), and the spinal accessory nerve (XI), with other cranial lower nerves monitored less frequently. Morbidity from trauma to these nerves is significant and obvious, such as unilateral facial paresis. Although functional restorative surgery is usually considered to repair the effects of such an insult, the importance of preventing nerve injury in head and neck surgery is obvious. This article focuses on the anesthetic considerations pertinent to IONM of peripheral cranial nerves during otolaryngologic-head and neck surgery. The specific modality of IONM is EMG, both spontaneous and evoked.

[Regional anaesthesia for head and neck surgery]. / Anesthésie locorégionale pour la chirurgie esthétique de la face et du cou.

Plastic surgery is more and more developing. Facial blocks are adapted to surgical procedures performed in this setting. They are easy to perform and may prolong postoperative analgesia. Facial blocks may be used in ambulatory surgery as a single technique or combined with general anaesthesia or intravenous sedation. After a reminding of facial nerve anatomy, facial and cervical blocks are described with their indications. Guidelines for performance and monitoring are also indicated.

The petrosal nerves: anatomy, pathology, and surgical considerations.

The literature lacks a comprehensive review of the petrosal nerves, which often have a complicated course and nomenclature. The medical literature was reviewed comprehensively for information regarding the anatomy, pathology, and surgery of the petrosal nerves. The terminology and anatomy of the petrosal nerves are often complicated. Our review found multiple nomenclatures used in the description of these structures. Information regarding the petrosal nerves may assist those who observe or operate at or near the skull base. To our knowledge, this is the first comprehensive review of these structures.

Study of descendent course of buccal nerve in adults individuals / Estudio del trayecto descendente del nervio bucal en individuos adultos

The knowledge of the buccal nerve anatomy is of fundamental importance not only for the anesthesia but also for a safe intervention in the retromolar area. The aim of this work was to study its trajectory, in the area where it is related to the anterior margin of the ramus of the mandible, therefore providing important data for a safe intervention in the region. In this study we used 10 hemi-heads from male and female adults, from different ethnic groups. They were fixed in formol, and belong to the Anatomy Laboratory at the Faculty of Dentistry in Araraquara UNESP. These hemi-heads were dissected by lateral access, preserving the buccal nerve in its trajectory related to the anterior margin of the ramus of the mandible until its penetration in the buccinator muscle. Next, we desinserted the masseter muscle so that all the ramus of the mandible were exposed. Then, the following measurements were carried out: from the base of the mandible until the buccal nerve and from the base of the mandible until the apices of the mandibular coronoid process. These measurements were accomplished with a Mitutoyo CD-6'' CS digital paquimeter. The following average values were obtained: 32.26 mm (to the left side) and 32.04 mm (to the right side), from the base of the mandible until the buccal nerve and 59.09 mm (to the left side) and 58.95 mm (to the right side) from the base of the mandible until the apices of the coronoid process. We have concluded that normally, the buccal nerve crosses the anterior margin of the ramus of the mandible in an area which is above the superior half of the ramus of the mandible and also that the interventions in the retromolar region do not offer great risks of injury in the buccal nerve.

El conocimiento de la anatomía del nervio bucal es de importancia fundamental no sólo para la anestesia, sino también para una intervención segura en la zona retromolar. El objetivo de este trabajo fue estudiar la trayectoria del nervio bucal, en la zona en que se relaciona con el margen anterior de la rama de la mandíbula, proporcionando datos importantes para una intervención segura en la región. En este estudio fueron utilizadas 10 hemi-cabezas de hombres y mujeres adultos, de diferentes grupos étnicos. Las cabezas fueron fijadas en formol, y pertenecen al Laboratorio de Anatomía de la Facultad de Odontología de Araraquara UNESP. Las hemi-cabezas fueron disecadas por medio de un acceso lateral, preservando al nervio bucal en su trayectoria en relación con el margen anterior de la rama de la mandíbula hasta su penetración en el músculo buccinador. A continuación, el músculo masetero fue desinsertado de modo que toda la rama de la mandíbula fue expuesta. A continuación, se llevaron a cabo las siguientes mediciones: desde la base de la mandíbula hasta el nervio bucal y de la base de la mandíbula hasta los ápices de los procesos coronoides mandibular. Estas mediciones se realizaron con un caliper digital CD-6'' CS Mitutoyo. Los siguientes valores promedio fueron obtenidos: 32,26 mm (a la izquierda) y 32,04 mm (a la derecha) de la base de la mandíbula hasta el nervio bucal y 59,09 mm (a la izquierda) y 58,95 mm (a la derecha) de la base de la mandíbula hasta los ápices de los procesos coronoides. En conclusión, normalmente, el nervio bucal cruza el margen anterior de la rama de la mandíbula en una zona que está por encima de la media superior de la rama de la mandíbula, y también que las intervenciones en la región retromolar no ofrecen grandes riesgos de lesiones en el nervio bucal.

Electrophysiological and immunofluorescence characterization of Ca(2+) channels of acutely isolated rat sphenopalatine ganglion neurons.

The sphenopalatine ganglion (SPG) is the main parasympathetic ganglion that is involved in regulating cerebral vascular tone and gland secretion. SPG neurons have been implicated in some types of migraine headaches but their precise role has yet to be determined. In addition, very little information is available regarding ion channel modulation by neurotransmitters that are involved in the parasympathetic drive of SPG neurons. In this study, acute isolation of adult rat SPG neurons was developed in order to begin the electrophysiological characterization of this ganglion. Under our dissociation conditions, the average number of neurons obtained per ganglion was greater than 1200. Immunofluorescence imaging results showed positive labeling with acetylcholinesterase (AChE), confirming the parasympathetic nature of SPG neurons. On the other hand, weak tyrosine hydroxylase immunostaining was observed in these neurons. Whole-cell patch-clamp recordings revealed that most of the Ca(2+) current is carried by N-type (53%) and SNX-482 resistant R-type (30%) Ca(2+) channels. In addition, Ca(2+) currents were inhibited in a voltage-dependent manner following exposure to oxotremorine-M (Oxo-M), norepinephrine and ATP via muscarinic acetylcholine receptor 2 (M(2) AChR) subtype, adrenergic and P2Y purinergic receptors, respectively. The peptides VIP and angiotensin II failed to modulate Ca(2+) currents, suggesting that these receptors are not present on the SPG soma or do not couple to Ca(2+) channels. In summary, our data suggest that the Ca(2+) current inhibition mediated by Oxo-M, NE and ATP in adult rat SPG neurons plays an integral part in maintaining parasympathetic control of cranial functions.

Landmarks for the identification of the cutaneous nerves of the occiput and nuchal regions.

Although surgical procedures are often performed over the posterior head and neck, surgical landmarks for avoiding the cutaneous nerves in this region are surprisingly lacking in the literature. Twelve adult cadaveric specimens underwent dissection of the cutaneous nerves overlying the posterior head and neck, and mensuration was made between these structures and easily identifiable surrounding bony landmarks. All specimens were found to have a third occipital nerve (TON), lesser occipital nerve (LON), and greater occipital nerve (GON), and we found that the TON was, on average, 3 mm lateral to the external occipital protuberance (EOP). Small branches were found to cross the midline and communicate with the contralateral TON inferior to the EOP in the majority of sides. The mean diameter of the main TON trunk was 1.3 mm. This trunk became subcutaneous at a mean of 6 cm inferior to the EOP. The GON was found to lie at a mean distance of 4 cm lateral to the EOP. On all but three sides, a small medial branch was found that ran medially from the GON to the TON approximately 1 cm superior to a horizontal line drawn through the EOP. The GON was found to pierce the semispinalis capitis muscle on average 2 cm superior to the intermastoid line. The mean diameter of the GON was 3.5 mm. The GON was found to branch into medial and lateral branches on average 0.5 cm superior to the EOP. The LON was found to branch into a medial and lateral component at approximately the midpoint between a horizontal line drawn through the EOP and the intermastoid line. The main LON trunk was found on average 7 cm lateral to the EOP. In specimens with a mastoid branch of the great auricular nerve (GAN), this branch was found at a mean of 9 cm lateral to the EOP. The main trunk of this branch of the GAN was found to lie on average 1 cm superior to the mastoid tip. Easily identifiable bony landmarks for identification of the cutaneous nerves over the posterior head and neck can aid the surgeon in more precisely identifying these structures and avoiding complications. Although the occipital nerves were found to freely communicate with one another, avoiding the main nerve trunks could lessen postoperative or postprocedural morbidity. Moreover, clinicians who need to localize the occipital nerves for the treatment of occipital neuralgia could do so more reliably with better external landmarks.

Precraniate origin of cranial motoneurons.

The craniate head is innervated by cranial sensory and motor neurons. Cranial sensory neurons stem from the neurogenic placodes and neural crest and are seen as evolutionary innovations crucial in fulfilling the feeding and respiratory needs of the craniate "new head." In contrast, cranial motoneurons that are located in the hindbrain and motorize the head have an unclear phylogenetic status. Here we show that these motoneurons are in fact homologous to the motoneurons of the sessile postmetamorphic form of ascidians. The motoneurons of adult Ciona intestinalis, located in the cerebral ganglion and innervating muscles associated with the huge "branchial basket," express the transcription factors CiPhox2 and CiTbx20, whose vertebrate orthologues collectively define cranial motoneurons of the branchiovisceral class. Moreover, Ciona's postmetamorphic motoneurons arise from a hindbrain set aside during larval life and defined as such by its position (caudal to the prosensephalic sensory vesicle) and coexpression of CiPhox2 and CiHox1, whose orthologues collectively mark the vertebrate hindbrain. These data unveil that the postmetamorphic ascidian brain, assumed to be a derived feature, in fact corresponds to the vertebrate hindbrain and push back the evolutionary origin of cranial nerves to before the origin of craniates.