Therapeutic effects of exendin-4 on spinal cord injury via restoring autophagy function and decreasing necroptosis in neuron.

AIMS: Necroptosis is one of programmed death that may aggravate spinal cord injury (SCI). We aimed to investigate the effect and mechanism of exendin-4 (EX-4) on the recovery of motor function and necroptosis after SCI. METHODS: The SD rats with left hemisection in the T10 spinal cord as SCI model were used. The behavior tests were measured within 4 weeks. The effects of EX-4 on necroptosis-associated proteins and autophagy flux were explored. In addition, the SHSY5Y cell model was introduced to explore the direct effect of EX-4 on neurons. The effect of lysosome was explored using mTOR activator and AO staining. RESULTS: EX-4 could improve motor function and limb strength, promote the recovery of autophagy flux, and accelerate the degradation of necroptosis-related protein at 3 d after injury in rats. EX-4 reduced lysosome membrane permeability, promoted the recovery of lysosome function and autophagy flux, and accelerated the degradation of necroptosis-related proteins by inhibiting the phosphorylation level of mTOR in the SHSY5Y cell model. CONCLUSION: Our results demonstrated that EX-4 may improve motor function after SCI via inhibiting mTOR phosphorylation level and accelerating the degradation of necroptosis-related proteins in neurons. Our findings may provide new therapeutic targets for clinical treatment after SCI.

Hemisection: A Paradigm Shift in Prolonging Tooth Viability.

Splitting a molar means removing or separating the root and the accompanying crown portion. Hemisection of a damaged tooth aids in preserving the tooth structure and the existing alveolar bone surrounding the preserved root while also enabling the installation of a fixed prosthesis. This case report defines hemisection as an effective modality for preserving carious mandibular first molars with periodontal and periapical pathology.

Hemisection: A Boon for the Hopeless Tooth.

If left untreated, an inflammatory periodontal disease eventually leads to attachment loss. This may have an impact on a multi-rooted tooth's bifurcation or trifurcation. The division of a tooth with two roots into two distinct parts is known as hemisection. Hemisection is the term used to describe the removal or separation of a two-rooted tooth's root and crown, most likely a mandibular molar. Compared to other treatment options, hemi-sectioning the affected tooth can help preserve the tooth's structure and alveolar bone. Careful selection of cases is essential for the long-term success of the procedure. In this case report, in contrast to the more common option of extracting the natural tooth, a treatment option is discussed for molars with extensive decay that threatens tooth loss. Therefore, this option should be discussed with patients when deciding on a course of treatment, and it may be a good substitute for extraction and implant therapy, particularly in cases of advanced endo-perio lesions.

Management options and long-term follow-ups for permanent double incisors: six to eleven-year case reports.

BACKGROUND: Double teeth are dental anomalies that can lead to aesthetic and orthodontic problems. CASE PRESENTATION: This report discusses two cases involving the multidisciplinary management of permanent maxillary left lateral incisors fused with a supernumerary tooth in two girls aged 9 and 10. Following intraoral and radiographic examinations, one was diagnosed with fusion, and the other was diagnosed with concrescence. The crown of the fused incisor was separated using a burs and extracted intraorally. The concrescent incisor was separated along its length using a laser and intentionally replanted extraorally. After a 6-year follow-up, no pathological signs were observed in the fused incisor. However, after an 11-year follow-up, external resorption was observed in the concrescent incisor. CONCLUSIONS: Both incisors remained asymptomatic throughout the observation period. This case report highlights two different and effective methods employed to preserve the natural function, form, and aesthetics of double incisors.

Finite element evaluation of dentin stress changes following different endodontic surgical approaches.

The aim was to compare the effect of different endodontic surgical treatments on the stress distributions in dentin of a simulated first mandibular molar tooth using the finite element analysis method. Three surgical endodontic procedures (apical resection, root amputation, and hemisection) were simulated in a first mandibular molar. Biodentine or mineral-trioxide-aggregate was used to repair the surgery site in apical resection and root amputation models; the remaining root canal spaces were filled with gutta-percha. Access cavities were restored using resin composite. In hemisection model, root canal was filled with gutta-percha, and coronal restoration was finished with a monolithic zirconia crown. A sound tooth model was created as a control model. An oblique force of 300 N angled at 45° to the occlusal plane was simulated. Maximum von Mises stresses were evaluated in dentin near the surgery regions and the entire tooth. Apical resection/Biodentine and apical resection/mineral-trioxide-aggregate models generated maximum von Mises stresses of 39.001 MPa and 39.106 MPa, respectively. The recorded maximum von Mises stresses in root amputation models were 66.491 MPa for root amputation/Biodentine and 73.063 MPa for root amputation/mineral-trioxide-aggregate models. The highest maximum von Mises stress value among all models was observed in the hemisection model, measuring 138.87 MPa. Hemisection induced the highest von Mises stresses in dentin, followed by root amputation and apical resection. In apical resection, Biodentine and mineral-trioxide-aggregate did not show a significant difference in stress distribution. Biodentine in root amputation may lead to lower stresses compared to mineral-trioxide-aggregate.

Hemisección radicular, alternativa terapéutica en fracturas radiculares verticales. Presentación de un caso / Root Hemisection, Therapeutic Alternative in Vertical Root Fractures. A Case Report

Las fracturas radiculares verticales son los traumatismos de peor pronóstico para el diente, por constituir la exodoncia su tratamiento convencional. Se presenta un paciente masculino de 57 años de edad, acude a consulta de urgencia de la Clínica Estomatológica Artemio Mastrapa Rodríguez, de Holguín, con dolor a la masticación en 14, al examen clínico fractura vertical entre las cúspides que separa las raíces, dolor a la percusión y movilidad del fragmento palatino. Se realizó hemisección de la raíz palatina, tratamiento de conducto de la raíz vestibular del 14, luego tallado y restauración final de cúspide vestibular con resina fotopolimerizable. En este caso la hemisección de la raíz palatina del 14 mantuvo la estética en un paciente completamente dentado sin usar otras aparatologías ni producir alteraciones al equilibrio bucofacial. Al año mostró evolución satisfactoria, comprobada con exámenes clínicos y radiográficos. Se concluyó que la hemisección radicular puede ser una alternativa conservadora en casos de fracturas radiculares verticales en premolares superiores.

The vertical root fractures are the traumatisms of worse prognosis for the tooth, since the conventional treatment is constituted by exodontia. We report a case of a 57-year-old male patient who attended the emergency room of the Artemio Mastrapa Rodríguez Stomatological Clinic, Holguin with pain at chewing in 14, to the clinical examination vertical fracture between the cusps that separates the roots, pain to percussion and mobility of the palatal fragment. Hemisection of the palatal root was performed, treatment of vestibular root canal of 14, then carving and final restoration of vestibular cusp with photopolymerisable resin. After surgery, the vestibular cuspid was carved and received a definite restoration with light cure resin. In this case, the hemisection of the palatal root of 14 maintained aesthetics in a completely dentate patient without using other appliances or producing alterations in the orofacial balance. The radicular hemisection can be a conservative alternative in cases of upper premolars with verticals roots fractures. It was concluded that radicular hemisection can be a conservative alternative in cases of vertical root fractures in upper premolars.

Brown-Sequard, a restless mind / Brown-Sequard, uma mente inquieta

Brown-Séquard, a remarkable medical personality of the 19 th century, was born in a small island of the Indian Ocean. He travelled over the world exerting his skills: a successful physician, and an innovative researcher, with a very ample range of interests. His favored subject was the nervous system. The spinal cord was studied extensively, with novel and important discoveries on the sensory pathways. He identified cases with spinal cord hemisection, and described the clinical presentation corresponding to a syndrome which bears his name (Brown-Séquard syndrome), for which he is best known among neurologists. Regarding the brain, he proposed nine mental and physical functions (organs) related to dynamically interconnected cell clusters, in harmony with the “ réseau de cellules anastomosées ”, “ activités dynamogeniques et inhibitrices ”, and “ action à distance ” concepts. Finally, he is considered by some as the “father” of endocrinology, due to his studies on glands and their secretions.

Brown-Séquard, notável personalidade médica do século 19, nasceu em uma pequena ilha do Oceano Índico. Viajou pelo mundo exercendo suas habilidades: médico de sucesso e pesquisador ousado, com gama muito extensa de interesses. Seu assunto favorito era o sistema nervoso. A medula foi estudada de modo amplo, com descobertas novas e importantes sobre as vias sensitivas. Identificou casos com hemisseção medular e descreveu o quadro clínico correspondente a uma síndrome que leva seu nome (síndrome de Brown-Séquard), motivo pelo qual é melhor conhecido entre os neurologistas. Considerando o cérebro, propôs nove funções (órgãos) mentais e físicas relacionadas de modo dinâmico a conglomerados celulares, em harmonia com seus conceitos de “ réseau de cellules anastomosées ”, “ activités dynamogeniques et inhibitrices ” e “ action à distance ”. Finalmente, ele é considerado por alguns como “pai” da endocrinologia, devido seus estudos sobre glândulas e suas secreções.

Brown-Séquard, um pesquisador itinerante - De uma pequena ilha do Oceano Índico para o mundo / Brown-Séquard, a wandering researcher - From a small island of the Indian Ocean to the world

Brown-Séquard, pesquisador e médico, foi uma das mais extraordinárias personalidades do século XIX. Nascido em uma pequena ilha no meio do Oceano Índico, viajou pelo mundo exercendo suas habilidades de médico respeitável, além de pesquisador inovador, experimental e clínico. Seus interesses eram amplos, principalmente na área da neurologia. A medula foi estudada durante décadas, dando inicialmente lugar à sua tese de doutorado. Esses estudos levaram à descrição de uma síndrome devida à hemisseção da medula, que traz seu nome e é um dos seus feitos mais conhecidos entre os neurologistas. Outros variados assuntos levaram à produção de grande número de trabalhos, publicados em livros e periódicos reconhecidos.

Brown-Séquard, researcher and physician, was one of the most amazingpersonality of the 19th century. Born in a small island in the middleof the Indian Ocean, he travelled over the world exerting his skills of a reputable physician and an innovative experimental and clinical researcher. His interests were ample, mainly in the neurological area. The spinal cord was studied for many decades, ensuing initially his doctorate thesis. These studies led to a description of a syndrome due to hemisection of the cord, that bear his name, one of his most known feat among neurologists. Other varied subjects led to the production of a large number of works, published in books and renowned journals.