Sema3A secreted by sensory nerve induces bone formation under mechanical loads / 国际口腔科学杂志·英文版

Bone formation and deposition are initiated by sensory nerve infiltration in adaptive bone remodeling. Here, we focused on the role of Semaphorin 3A (Sema3A), expressed by sensory nerves, in mechanical loads-induced bone formation and nerve withdrawal using orthodontic tooth movement (OTM) model. Firstly, bone formation was activated after the 3rd day of OTM, coinciding with a decrease in sensory nerves and an increase in pain threshold. Sema3A, rather than nerve growth factor (NGF), highly expressed in both trigeminal ganglion and the axons of periodontal ligament following the 3rd day of OTM. Moreover, in vitro mechanical loads upregulated Sema3A in neurons instead of in human periodontal ligament cells (hPDLCs) within 24 hours. Furthermore, exogenous Sema3A restored the suppressed alveolar bone formation and the osteogenic differentiation of hPDLCs induced by mechanical overload. Mechanistically, Sema3A prevented overstretching of F-actin induced by mechanical overload through ROCK2 pathway, maintaining mitochondrial dynamics as mitochondrial fusion. Therefore, Sema3A exhibits dual therapeutic effects in mechanical loads-induced bone formation, both as a pain-sensitive analgesic and a positive regulator for bone formation.

Compresión percutánea del ganglio de Gasser y raíz trigeminal con balón en el tratamiento de la neuralgia del trigémino / Percutaneous compression of the Gasser ganglion and trigeminal root with balloon in the treatment of trigeminal neuralgia

Introducción: Introducción: La compresión percutánea con balón (CPB) es una de las técnicas estándar para el tratamiento de la neuralgia del trigémino. El objetivo de este estudio es evaluar la eficacia de la compresión percutánea con balón (CPB) del ganglio de Gasser y raíz trigeminal en el tratamiento de la neuralgia del trigémino (TN). Métodos: Se usó un estudio observacional analítico de cohorte prospectivo. Un total de 293 pacientes con neuralgia del trigémino fueron tratados con la CPB entre octubre de 2008 y octubre de 2019 en Lima, Perú. Los datos fueron obtenidos de los registros hospitalarios y entrevistas. La CPB se realizó bajo sedación con propofol y remifentanilo. Se administróoxígeno a través de cánula nasal y se monitorizó la frecuencia cardíaca y la presión arterial durante todo el procedimiento. Elprocedimiento se realizó usando fluoroscopia con arco en C para facilitar la introducción de la aguja 14 G hasta que se ingresaal agujero oval y la visualización del catéter Fogarty 4F inflado en el cavum de Meckel. En la posición correcta, generalmenteaparece claramente definido una forma de pera o de reloj de arena después de la inyección de 0.5-1 ml de material decontraste. Resultados: La edad media fue de 64.2 años (rango 27-90). Treinta y seis pacientes (12%) tuvieron otros procedimientosquirúrgicos previos. Doscientos sesenta y dos pacientes (89.4%) experimentaron un alivio inmediato de la neuralgia despuésdel procedimiento. Se obtuvo un balón con forma de pera en 162 casos (55.3%), reloj de arena 73 (24.9%) y oval 58 (19.8%). En 245 pacientes (83.6%) el balón se mantuvo inflado durante 60 - 90 segundos. Es crucial obtener una forma de pera o de reloj de arena porque este es probablemente el factor más importante para obtener un buen alivio del dolor y duradero. Todo el procedimiento dura unos 15 minutos. La hipoestesia hemifacial después del procedimiento fue moderada o severa en el 76.5% de los pacientes. A los tres meses, la mayoría de los pacientes tienen una recuperación significativa en la sensibilidad facial, que continúa recuperándose con el tiempo. Todos los pacientes tuvieron alguna dificultad transitoria para masticar en el lado afectado. Se observó recurrencia en 26 pacientes (9.2%) en un tiempo de seguimiento de 6 meses a 11 años (5.75 años). La forma más común de balón asociada con recurrencia fue la oval (65.4%).Conclusiones: La CPB es técnicamente simple, bien tolerada por los pacientes. La tasa de éxito de la operación es alta. Los pacientes con balón en forma de pera o de reloj de arena obtuvieron los mejores resultados.

Introduction: Percutaneous balloon compression (PBC) is one of the standards techniques for the treatment of trigeminal neuralgia.The objective of this study is to evaluate the efficacy of PBC of the Gasserian ganglion and trigeminal rootlets as treatment for trigeminal neuralgia (TN). Methods: A prospective cohort analytical observational study was used. A total of 293 patients with trigeminal neuralgia were treated with PBC between october 2008 and October 2019 in Lima, Perú. The data were obtained from hospital records and interviews. PBC was performed under sedation with propofol and remifentanil. Oxygen was administered through nasal cannula and the heart rate and blood pressure were monitored throughout the procedure. The procedure is carried out with C-arm fluoroscopy to facilitate the introduction of the 14 G needle until the foramen oval is entered and the visualization of the inflated catheter Fogarty 4F in the Meckel ́s cave. Once in the right position, a clearly defined pear shape or hourglass is seen after injection of 0.5 ­ 1 mL of contrast material. Results: The mean age was 64.2 years (range, 27-90). Thirty-six patients (12%) had other previous surgical procedures. Two hundred sixty-two patients (89.4%) experienced immediate relief from neuralgia following the procedure. A pear-shaped balloon was obtained in 162 cases (55.3%), hourglass 73 (24.9%) and oval 58 (19.8%). In 245 patients (83.6%) the balloon is kept inflated for 60­90 seconds. It is crucial to obtain a pear shape or hourglass because this probably is the most significant factor for obtaining good, long-lasting pain relief. The whole procedure takes 15 minutes. Following the procedure, hemifacial hypoesthesia was moderate or severe in 76.5% of patients. Most patients have a significant recovery in facial sensitivity at three months post-procedure and continue to improve over time. All patients faced some transient difficulty chewing in the affected side. Recurrence was observed in 26 patients (9.2%) during a follow-up time of 6 months to 11 years (5.75 years). The most common form of balloon associated with recurrence was oval (65.4%).Conclusions: PBC is a technically simple, well tolerated by patients. The operation success rate is high. Patients with pear or hourglass shape balloon obtained the best results.

Termocoagulación por radiofrecuencia de ganglio de Gasser para el tratamiento de neuralgia trigeminal, resultados de 11 años / Gasser's ganglion radiofrequency thermocoagulation for the treatment of trigeminal neuralgia, 11-year results

Objetivos: Describir resultados de los últimos 11 años en el tratamiento de neuralgia del trigémino con termocoagulación por radiofrecuencia, analizar variables relacionadas a complicaciones y resultados. Material y Métodos: Estudio retrospectivo, descriptivo, longitudinal, comparativo y analítico. Se analizaron los resultados de los últimos 11 años de nuestro servicio evaluando las temperaturas de las lesiones armando dos grupos, de 65°C-70°C y 71°C-75°C para analizar su relación con resultados y complicaciones. Resultados: Se trataron 59 pacientes en los cuales se realizaron 74 procedimientos, la edad media fue 59.22 años (±13,45). Se observó recidiva en 23 procedimientos con una tasa global de 31%. El tiempo medio de recidiva fue de 28,19 meses (±26,21). El tiempo medio de seguimiento fue de 33,10 meses (±33,49). El tiempo medio de evolución del dolor, previo al primer procedimiento, fue de 5,35 años (±4,37). Analizando los grupos se observó que no existía relación significativamente estadística (p = 0,74) entre el grupo de pacientes de 65ºC-70ºC y el grupo de 71ºC-75ºC y recidiva. No se observó relación estadísticamente significativa entre el grupo de 65ºC-70ºC y el grupo de 71ºC-75ºC y tiempo de recidiva (p=0,12). Se observó más pacientes con hipoestesia inmediata en el grupo de pacientes de 65ºC-70ºC, sin significación estadística (p=0,47). Conclusión: La termocoagulación por radiofrecuencia de ganglio de Gasser es un procedimiento accesible, mínimamente invasivo que demostró buenos resultados y buen manejo del dolor con bajo índice de complicaciones.

Objectives: Describe results of the last 11 years in the treatment of trigeminal neuralgia with radiofrequency thermocoagulation, analyze variables related to complications and results. Methods: Retrospective, descriptive, longitudinal, comparative and analytical study. The results of the last 11 years of our service were analyzed by assessing the temperatures of the lesions by assembling two groups, 65° C-70° C and 71 ° C-75° C to analyze their relationship with results and complications. Results: 59 patients were treated in which 74 procedures were performed; the mean age was 59.22 years (± 13.45). Recurrence was observed in 23 procedures with an overall rate of 31%. The average recurrence time was 28.19 months (± 26.21). The average follow-up time was 33.10 months (± 33.49). The average time of pain evolution, prior to the first procedure, was 5.35 years (± 4.37). Analyzing the groups, it was observed that there was no significant statistical relationship (p = 0.74) between the group of patients from 65ºC-70ºC and the group from 71ºC-75ºC and recurrence. No statistically significant relationship was observed between the 65ºC-70ºC group and the 71ºC-75ºC group and recurrence time (p = 0.12). More patients with immediate hypoaesthesia were observed in the group of patients from 65ºC-70ºC, without statistical significance (p = 0.47). Conclusion: Gasser's ganglion radiofrequency thermocoagulation is an accessible, minimally invasive procedure that demonstrated good results and good pain management with a low complication rate

Infecção latente pelo herpesvírus bovino tipo 1 em búfalos (Bubalus bubalis) no Rio Grande do Sul / Bovine herpesvirus type 1 latent infection in buffalo (Bubalus bubalis) in Rio Grande do Sul

Apesar dos bovinos serem considerados os hospedeiros naturais do BoHV-1, estudos sorológicos têm sugerido que búfalos podem ser suscetíveis ao BoHV-1 e a outros alfa-herpesvírus geneticamente relacionados. O objetivo deste estudo foi detectar a presença de DNA viral de BoHV-1 em 202 amostras de gânglios trigêmeos de búfalos, pela técnica de semi-nested PCR, para detecção de um segmento do gene codificante da glicoproteína D (gD) do BoHV-1. Além disso, 242 amostras de soro foram analisadas pela técnica de soroneutralização (SN) para a detecção de anticorpos neutralizantes contra BoHV-1, BoHV-5 e BuHV. Todas as amostras clínicas foram coletadas em um matadouro na cidade de Pelotas, RS, Brasil. O DNA de BoHV-1 foi detectado em 61 (30,1%) gânglios, e os resultados da SN demonstraram que 27,6% dos animais apresentaram anticorpos contra, pelo menos, um dos vírus testados. O sequenciamento genômico e a análise de 14 amplicons confirmaram a presença do DNA do BoHV-1 nos tecidos analisados. Em resumo, os resultados indicam que o BoHV-1 está distribuído em rebanhos bubalinos provenientes da região Sul do Brasil. Entretanto, são necessárias investigações adicionais, no sentido de elucidar o papel exato dos búfalos na epidemiologia das infecções pelo BoHV-1.(AU)

Although bovines are natural hosts for BoHV-1, serologic studies in several countries have suggested that buffaloes (Bubalus bubalis) may be susceptible to BoHV-1 and other genetically related alphaherpesvirus. This study aimed to investigate the presence of BoHV-1 DNA in trigeminal ganglia from 202 buffaloes by a semi-nested PCR to amplify partially the glycoprotein D (gD) gene of BoHV-1. Additionally, 242 serum samples were tested by serum neutralization (SN) for the detection of antibodies against BoHV-1, BoHV-5 and BuHV. All clinical samples were collected in a slaughterhouse located in Pelotas, RS, Brazil. BoHV-1 DNA was detected in 61 (30.1%) of the samples and SN revealed 27.6% of the animals with neutralizing antibodies against at least one of the tested viruses. Nucleotide sequencing of 15 amplicons followed by BLAST analysis confirmed the presence of BoHV-1 DNA in the analyzed tissues. Taken together, these data indicate that BoHV-1 infection is distributed in buffaloes in southern Brazil. However, the role of buffaloes in the BoHV-1 epidemiology needs further investigation.(AU)

Role of neuron and non-neuronal cell communication in persistent orofacial pain

It is well known that trigeminal nerve injury causes hyperexcitability in trigeminal ganglion neurons, which become sensitized. Long after trigeminal nerve damage, trigeminal spinal subnucleus caudalis and upper cervical spinal cord (C1/C2) nociceptive neurons become hyperactive and are sensitized, resulting in persistent orofacial pain. Communication between neurons and non-neuronal cells is believed to be involved in these mechanisms. In this article, the authors highlight several lines of evidence that neuron-glial cell and neuron macrophage communication have essential roles in persistent orofacial pain mechanisms associated with trigeminal nerve injury and/or orofacial inflammation.

Trigeminal Neuralgia Resulting from Delayed Cervical Cord Compression after Acute Traumatic Fracture of Odontoid Process / 대한신경손상학회지

Trigeminal neuralgia is caused by compression of trigeminal nerve root and it leads to demyelination gradually. It was almost idiopathic and occurred unexpected. The upper cervical spinal cord contains the spinal trigeminal tract and nucleus. Fibers with cell bodies in the trigeminal ganglion enter in the upper pons and descend caudally to C2 level. We experienced a rare patient with facial pain, which was paroxysmal attack with severe pain after a clear event, cervical spinal injury (C2). So, this case reminds us of a possible cause of trigeminal neuralgia after a trauma of the head and neck.

Accuracy analysis of robotic assistant needle placement for trigeminal gasserian ganglion / 北京大学学报(医学版)

OBJECTIVE@#To evaluate the accuracy and feasibility of a custom robot system guided by optical navigation for needle puncture on trigeminal gasserian ganglion.@*METHODS@#A synthetic human skull model was used, with plasticine placed around the skull base to imitate the human soft tissue. Cone beam CT (CBCT) scanning was performed before the operation. With image data transferred to the graphical user interface of the computer workstation, the oval foramen was selected as the target and the "skin entry point" was also determined by the surgeon on the surgical planning software. Thus the needle trajectory was eventually planned. The skull model was fixed firmly to the trial table with a head clamp and relative size of the trial table was the same as a standard operating table. Following point-based registration, the data were sent to the robot control unit. Only after the surgeon's confirmation, the needle was automatically inserted into the intended target by the robot guided by optical navigation. When the procedure was completed, the instantaneous data of the needle tip orientation acquired by navigation system was sent back to the computer workstation for accuracy verification by calculating the geometric distance between the needle tip and the planning target after matrix transformation. Subsequently, after the needle had been released, CBCT scanning was also acquired to make image fusion of the preoperative skull and the postoperative skull. The data of the needle tip orientation was acquired on the postoperative image and the accuracy was re-verified by calculating the geometric distance between the needle tip and the planning target after matrix transformation. IBM SPSS Statistics 20 was used for statistical analysis and the paired t-test was used to compare the differences in the accuracy measured by the intraoperative navigation and postoperative image fusion.@*RESULTS@#All 20 interventions were successfully located in oval foramen at the first needle insertion. The mean deviation of the needle tip was (0.56±0.07) mm (measured by the navigation system) and (1.49±0.14) mm (measured by the image fusion), respectively (P<0.001).@*CONCLUSION@#The experimental results show the robot system is efficient and reliable. The navigation accuracy is one of the most significant factors in robotic procedures.

Involvement of intrathecal activation of MrgC receptor in pathological pain and morphine tolerance / 生理学报

Rodent MrgC receptor (Mas-related G-protein-coupled receptor subtype C) shares 65% sequence homology and similarities in terms of expression pattern and binding profile with human Mas-related gene X receptor 1 (hMrgX1). Therefore, researchers generally explore the role of hMrgX1 by studying the function of MrgC receptor. Murine MrgC receptor is uniquely expressed in small-diameter neurons of dorsal root ganglia (DRG) and trigeminal ganglia (TG), which is closely related to the transmission process of pain. This review summarizes the analgesic effects of intrathecal activation of MrgC receptors in pathological pain and morphine tolerance.

Transient receptor potential Vanilloid 1-based gene therapy alleviates orthodontic pain in rats / 国际口腔科学杂志·英文版

Orthodontic pain that is induced by tooth movement is an important sequela of orthodontic treatment and has a significant effect on patient quality of life. Studies have shown that the high expression of transient receptor potential vanilloid 1 (TRPV1) in trigeminal ganglions plays a vital role in the transmission and modulation of orofacial pain. However, little is known about the role of TRPV1 in orthodontic pain. In this study, male Sprague-Dawley rats were randomly assigned to six groups to study the role of TRPV1 in the modulation of tooth-movement pain. The expression levels of TRPV1 mRNA and protein were determined by real-time PCR and western blot, respectively. Moreover, pain levels were assessed using the rat grimace scale (RGS). The role of TRPV1 in modulating tooth-movement pain was examined by injecting a TRPV1 antagonist into the trigeminal ganglia of rats. A lentivirus containing a TRPV1 shRNA sequence was constructed and transduced into the rats' trigeminal ganglia. The results showed that the expression levels of TRPV1 protein and mRNA were elevated following tooth-movement pain. Pain levels increased rapidly on the 1 day, peaked on the 3 day and returned to baseline on the 14 day. The TRPV1 antagonist significantly reduced tooth-movement pain. The lentivirus containing a TRPV1 shRNA sequence was able to inhibit the expression of TRPV1 and relieved tooth-movement pain. In conclusion, TRPV1-based gene therapy may be a treatment strategy for the relief of orthodontic pain.

Neurinomas del Trigemino: resección con abordaje endonasal transeptoesfenoidal convencional / Trigeminal neuromas: resection with a conventional transeptosphenoidal endonasal approach

Introducción: Los Neurinomas del nervio trigémino (NNT) son los segundos más comunes después de los neurinomas vestibulares, constituyendo cerca del 10% de los neurinomas intracraneales y menos del 0.5% de los tumores intracraneales. Los NNT pueden ocurrir en cualquier parte del curso del ganglio trigeminal y raíces del nervio trigémino. La mayor incidencia es entre los 30 y 40 años, siendo más frecuentemente en mujeres. Por sus características benignas el objetivo del manejo quirúrgico es con fines curativos, habiéndose propuesto diferentes técnicas quirúrgicas, lo que provoca que la elección de una en particular sea motivo de controversia. El propósito es presentar nuestra experiencia quirúrgica con abordaje endonasal transeptoesfenoidal convencional con el uso de espéculos asimétricos endoscópicamente asistidos en el manejo de NNT. Materiales y métodos: Se hizo el seguimiento de 3 pacientes diagnosticados con NNT en quienes se realizó resección por abordaje endonasal transeptoesfenoidal convencional (RETC), durante el periodo entre 2014 y 2015, en el Instituto Nacional de Cancerología, Bogotá D. C., Colombia. Se describen variables demográficas, clínicas, radiológicas y quirúrgicas. Resultados: Dos de ellos fueron hombres y una mujer, la edad media fue 48.3 años (32-60 a). El principal síntoma fue hipoestesia en hemicara. La localización en los 3 casos fue en la fosa craneal media y posterior derechas. Se realizó la resección quirúrgica siguiendo el abordaje propuesto, obteniendo buena visualización del tumor con resección total del tumor en 2 casos y subtotal en 1 caso, con resolución de sintomatología, menos complicaciones, menor estancia hospitalaria posoperatoria consecuente al abordaje menos invasivo respecto a otros tipos de abordaje, sin recidiva tumoral a 1 año de seguimiento. Conclusiones: Por medio de un abordaje endonasal transeptoesfenoidal convencional se proporciona una adecuada exposición de NNT, siendo posible resecarlos adecuadamente, por lo que este enfoque ofrece una excelente alternativa para el manejo de NNT con una baja morbimortalidad.

Introduction: Ten percent of intracranial neuromas and fewer than 0.5% of intracranial tumors are trigeminal nerve neuromas (TNN), which may occur anywhere along the course of the trigeminal nerve. They are most frequent in women between 30 and 40 years old. Since these tumors are characteristically benign tumors, the aim of surgical treatment is to be curative. Different surgical techniques have been described; however, which choice to employ remains controversial. This paper reports our surgical experience with the conventional trans-septosphenoidal endonasal approach, using endoscopically-assisted asymmetric specula, to resect TNN. Methods and materials: We reviewed three patients with a TNN who underwent tumor resection employing a conventional trans-septosphenoidal endonasal approach between 2014 and 2015 at the National Cancer Institute, Bogotá D.C., Colombia. Demographic, clinical, radiological, and surgical characteristics are described. Results: Two of our three patients were men and one a woman; the mean age was 48,3 (32- 60) years old. The main symptom was facial hypo-aesthesia. In all three patients, the tumor was located in the right mid and posterior cranial fossa. Surgical resection was performed with the proposed approach, obtaining good visualization of the tumor. Total tumor resection was achieved in two patients, and subtotal in one. We observed the complete resolution of symptoms, as well as fewer complications, and shorter postoperative hospital stays with our less-invasive approach relative to other more-invasive approaches described in the literature. No tumor recurrence was noted in the two patients who underwent total resection at one year of follow-up; the other patient remained asymptomatic. Conclusions: Utilizing a conventional trans-septosphenoidal endonasal approach, adequate exposure and resection of trigeminal nerve neuromas can be achieved. As such, this approach offers an excellent alternative to more-invasive techniques for managing TNN, being associated with low morbidity and mortality.

Preemptive application of QX-314 attenuates trigeminal neuropathic mechanical allodynia in rats

The aim of the present study was to examine the effects of preemptive analgesia on the development of trigeminal neuropathic pain. For this purpose, mechanical allodynia was evaluated in male Sprague-Dawley rats using chronic constriction injury of the infraorbital nerve (CCI-ION) and perineural application of 2% QX-314 to the infraorbital nerve. CCI-ION produced severe mechanical allodynia, which was maintained until postoperative day (POD) 30. An immediate single application of 2% QX-314 to the infraorbital nerve following CCI-ION significantly reduced neuropathic mechanical allodynia. Immediate double application of QX-314 produced a greater attenuation of mechanical allodynia than a single application of QX-314. Immediate double application of 2% QX-314 reduced the CCI-ION-induced upregulation of GFAP and p-p38 expression in the trigeminal ganglion. The upregulated p-p38 expression was co-localized with NeuN, a neuronal cell marker. We also investigated the role of voltage-gated sodium channels (Navs) in the antinociception produced by preemptive application of QX-314 through analysis of the changes in Nav expression in the trigeminal ganglion following CCI-ION. Preemptive application of QX-314 significantly reduced the upregulation of Nav1.3, 1.7, and 1.9 produced by CCI-ION. These results suggest that long-lasting blockade of the transmission of pain signaling inhibits the development of neuropathic pain through the regulation of Nav isoform expression in the trigeminal ganglion. Importantly, these results provide a potential preemptive therapeutic strategy for the treatment of neuropathic pain after nerve injury.

Effect of carbamazepine on tetrodotoxin-resistant Na⁺ channels in trigeminal ganglion neurons innervating to the dura

Migraine is a neurological disorder characterized by recurrent and disabling severe headaches. Although several anticonvulsant drugs that block voltage-dependent Na⁺ channels are widely used for migraine, far less is known about the therapeutic actions of carbamazepine on migraine. In the present study, therefore, we characterized the effects of carbamazepine on tetrodotoxin-resistant (TTX-R) Na⁺ channels in acutely isolated rat dural afferent neurons, which were identified by the fluorescent dye DiI. The TTX-R Na⁺ currents were measured in medium-sized DiIpositive neurons using the whole-cell patch clamp technique in the voltage-clamp mode. While carbamazepine had little effect on the peak amplitude of transient Na⁺ currents, it strongly inhibited steady-state currents of transient as well as persistent Na⁺ currents in a concentration-dependent manner. Carbamazepine had only minor effects on the voltage-activation relationship, the voltage-inactivation relationship, and the use-dependent inhibition of TTX-R Na⁺ channels. However, carbamazepine changed the inactivation kinetics of TTX-R Na⁺ channels, significantly accelerating the development of inactivation and delaying the recovery from inactivation. In the current-clamp mode, carbamazepine decreased the number of action potentials without changing the action potential threshold. Given that the sensitization of dural afferent neurons by inflammatory mediators triggers acute migraine headaches and that inflammatory mediators potentiate TTX-R Na⁺ currents, the present results suggest that carbamazepine may be useful for the treatment of migraine headaches.

Description of an in vivo oral mucosa HSV-1 infection model in mice

In this work, we established an in vivo murine model of herpes simplex virus type 1 (HSV1) infection involving inoculation by scarification of the oral mucosain order to study its dissemination towards the trigeminal ganglion (TG). Both viral DNA and infectious virions were detected on the third day postinfection (p.i.). Viral proteins revealed by immunohistochemistry were mainly found at seven days p.i., when the latencyassociated transcript (LAT) was also detected. This model simulated the dissemination process of HSV1, which could be used to study herpes pathogenesis starting in the oral mucosa (AU)

Con el propósito de estudiar la dispersión de del Herpes Simplex Virus tipo 1 (HSV1) desde la mucosa oral hasta los ganglios trigeminales, en el presente trabajo se estableció un modelo de infección en ratones, haciendo inoculación por escarificación en la mucosa oral. Tanto ADN viral como viriones infecciosos se detectaron en los ganglios trigeminales al dia 3 postinfección (p.i.). Las proteínas virales se detectaron principalmente al día 7 p.i. cuando los transcritos asociados a latencia también fueron encontrados. El modelo de infección simula adecuadamente el proceso de dispersión del HSV1 y puede ser usado para el estudio de la patogénesis por herpes después de la infección primaria en la mucosa oral (AU)

Effects of tetramethylpyrazine on trigeminal neuralgia induced by chronic constriction injury of infraorbital nerve in rats / 生理学报

Trigeminal neuralgia (TN) is a kind of recurrent transient and severe pain that is limited to the trigeminal nerve in one or more branches. The clinical incidence of TN is high, which seriously affects the quality of life of the patients and is difficult to cure. The present study investigated the effects of tetramethylpyrazine (TMP) on TN induced by chronic constriction injury of the infraorbital nerve (ION-CCI) in rats. Adult male Sprague-Dawley rats were randomly assigned to four groups: sham, sham treated with TMP (Sham+TMP), TN model (TN), and TN treated with TMP (TN+TMP). The rat TN model was established by ION-CCI and TMP (50 mg/kg) was injected intraperitoneally once a day for 2 weeks after operation. The mechanical response threshold was tested by the electronic von Frey filaments. The expression of CGRP in the trigeminal ganglia (TGs) of rats on the operative side was detected by RT-PCR, immunohistochemical staining and Western blot. In 15 days after operation, TN group showed a robust decrease in mechanical response threshold as compared with sham group. From day 9 to day 15 after operation, TMP treatment significantly suppressed the TN-induced mechanical hyperalgesia (P < 0.05). On day 15 after operation, RT-PCR, immunohistochemical staining and Western blot analysis showed an obvious increase in expression level of CGRP in TGs of TN group compared with sham group, which was downregulated by TMP treatment (P < 0.05). These results suggested that TMP might have a therapeutic potential for the treatment of TN through regulating CGRP expression in the TGs.

The effect of capsaicin on expression patterns of CGRP in trigeminal ganglion and trigeminal nucleus caudalis following experimental tooth movement in rats

ABSTRACT Objectives The aim of this study was to explore the effect of capsaicin on expression patterns of calcitonin gene-related peptide (CGRP) in the trigeminal ganglion (TG) and trigeminal subnucleus caudalis (Vc) following experimental tooth movement. Material and Methods Male Sprague-Dawley rats were used in this study and divided into small-dose capsaicin+force group, large-dose capsaicin+force group, saline+force group, and no force group. Closed coil springs were used to mimic orthodontic forces in all groups except for the no force group, in which springs were inactivated. Capsaicin and saline were injected into periodontal tissues. Rats were euthanized at 0 h, 12 h, 1 d, 3 d, 5 d, and 7 d following experimental tooth movement. Then, TG and Vc were obtained for immunohistochemical staining and western blotting against CGRP. Results Immunohistochemical results indicated that CGRP positive neurons were located in the TG, and CGRP immunoreactive fibers were distributed in the Vc. Immunohistochemical semiquantitative analysis and western blotting analysis demonstrated that CGRP expression levels both in TG and Vc were elevated at 12 h, 1 d, 3 d, 5 d, and 7 d in the saline + force group. However, both small-dose and large-dose capsaicin could decrease CGRP expression in TG and Vc at 1 d and 3 d following experimental tooth movement, as compared with the saline + force group. Conclusions These results suggest that capsaicin could regulate CGRP expression in TG and Vc following experimental tooth movement in rats.

The evaluation of curative effect of radiofrequency thermocoagulation on semilunar ganglion of aged patients with recurrent trigeminal neuralgia / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate curative effect and importance of radiofrequency thermocoagulation onsemilunar ganglion of aged patients with recurrent trigeminal neuralgia.@*METHOD@#112 cases with recurrent trigeminal neuralgia were performed with radiofrequency thermocoagulation on semilunar ganglion by puncture through skin under local anesthesia.@*RESULT@#The maintaining effective duration in 112 cases was 7.3 ± 1.3 years after primary therapy. After the first thermocoagulation, 89.28% (100/112) patients got the relief from pain immediately, 8 (7.14%) cases also recieved the same effect after twice treatment. However two cases (2.6%) had no effects. The total effective rate was 98.21%. During five follow-up years, VAS scores, dose of carbamazepine and satisfaction were better than those before the treatment. The effective rate was still over 57.5% within three years after the treatment. The recurrent risk increased obviously from 40 months after the treatment by Kaplan-Meier method.@*CONCLUSION@#Semilunar ganglion of radiofrequency thermocoagulation was an ideal option for old-age patients with trigeminal neuralgia. It can be performed repeatedly.

Incidence of pterygospinous and pterygoalar bridges in dried skulls of Koreans / 대한해부학회지

Understanding of morphological structures such as the sphenoid spine and pterygoid processes is important during lateral transzygomatic infratemporal fossa approach. In addition, osseous variations such as pterygospinous and pterygoalar bridges are significant in clinical practice because they can produce various neurological disturbances or block the passage of a needle into the trigeminal ganglion through the foramen ovale. Two hundred and eighty-four sides of Korean adult dry skulls were observed to carry out morphometric analysis of the lateral plate of the pterygoid process, to investigate, for the first time among Koreans, the incidence of the pterygospinous and pterygoalar bony bridges, to compare the results with those available for other regional populations, and to discuss their clinical relevance as described on literatures. The mean of maximum widths of the left and right lateral plates of the pterygoid process were 15.99 mm and 16.27 mm, respectively. Also, the mean of maximum heights of the left and right lateral plates were 31.02 mm and 31.01 mm, respectively. The ossified pterygospinous ligament was observed in 51 sides of the skulls (28.0%). Ossification of the pterygospinous ligament was complete in four sides (1.4%). In 47 sides (16.6%), the pterygospinous bridge was incomplete. The ossified pterygoalar ligament was observed in 24 sides of the skulls (8.4%). Ossification was complete in eight sides (2.8%) and incomplete in 16 sides (5.6%). This detailed analysis of the lateral plate of the pterygoid process and related ossification of ligaments can improve the understanding of complex clinical neuralgias associated with this region.

Cannabinoids increase mechanosensitivity of trigeminal ganglion neurons innervating the inner walls of rat anterior chambers via activation of TRPA1 / 华中科技大学学报（医学）（英德文版）

Our previous study found that some trigeminal ganglion (TG) nerve endings in the inner walls of rat anterior chambers were mechanosensitive, and transient receptor potential ankyrin 1 (TRPA1) was an essential mechanosensitive channel in the membrane. To address the effect of cannabinoids on the mechanosensitive TG nerve endings in the inner walls of anterior chambers of rat eye, we investigated the effect of the (R)-(+)-WIN55, 212-2 mesylate salt (WIN), a synthetic cannabinoid on their cell bodies in vitro. Rat TG neurons innervating the inner walls of the anterior chambers were labeled by 1,1'-dilinoleyl-3,3,3',3'-tetramethylindocarbocyanine, 4-chlorobenzenesulfona (FAST DiI). Whole cell patch clamp was performed to record the currents induced by drugs and mechanical stimulation. Mechanical stimulation was applied to the neurons by buffer ejection. WIN evoked inward currents via TRPA1 activation in FAST DiI-labeled TG neurons. WIN enhanced mechanosensitive currents via TRPA1 activation in FAST DiI-labeled TG neurons. Our results indicate that cannabinoids can enhance the mechanosensitivity of TG endings in the inner walls of anterior chambers of rat eye via TRPA1 activation.

Trigeminal purinergic P2X4 receptor involved in experimental occlusal interference-induced hyperalgesia in rat masseter muscle / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To explore the expression of purinergic p2X4 receptor (P2X4R) in trigeminal ganglion of rats after occlusal interference. Investigation of peripheral receptor mechanism of occlusal interference-induced masticatory muscle pain will aid the development of drug intervention against this condition.</p><p><b>METHODS</b>Experimental occlusal interference was established by application of 0.4 mm metal crown to the upper right first molar of male Sprague-Dawley rats. Real-time PCR assay was used to investigate P2X4R mRNA level in trigeminal ganglion in rats with occlusal interference for 3, 7, 10 and 14 days and in control rats without occlusal interference (n=5 in each). Retrograde labelling combining immunofluorescence was performed to evaluate the percentage of P2X4R-positive cells in masseter afferent neurons (n=5 in each group). Graded concentrations of P2XR antagonist TNP-ATP (0.1, 10, 125, 250, 500 μmol/L) or saline (n=5 in each group) was administrated in right masseter and the mechanical sensitivity of bilateral masseters was measured before occlusal interference application, before the injection, and 30 min as well as 60 min after the injection.</p><p><b>RESULTS</b>Compared with control rats (P2X4R mRNA: right side: 1.00±0.26, left side: 0.94± 0.21; percentage of P2X4R-positive masseter afferents: right side: [64.3±6.3]%, left side: [67.7±5.8]%), the level of P2X4R mRNA in bilateral trigeminal ganglia (right side: 5.98±3.56; left side: 5.06±2.88) of rats with occlusal interference for 7 days up-regulated (P<0.01) and the percentage of P2X4R-positive masseter afferent neurons(right side: [81.7±1.5]%; left side: [82.9±2.3]%) increased (P<0.05). Local administration of 10, 125, 250, 500 μmol/L TNP-ATP increased the mechanical withdrawal threshold in masseter 30 min after injection, compared with those before injection (P<0.05).</p><p><b>CONCLUSIONS</b>Increased expression of trigeminal P2X4R involves in the development of occlusal interference-induced masseter hyperalgesia.</p>