OBJECTIVES: With recent advances in nanoparticle manufacturing and applications, potential exposure to nanoparticles in various settings is becoming increasing likely. No investigation has yet been performed to assess whether respiratory tract exposure to cerium oxide (CeO2) nanoparticles is associated with alterations in protein signaling, inflammation, and apoptosis in rat lungs. METHODS: Specific-pathogen-free male Sprague-Dawley rats were instilled with either vehicle (saline) or CeO2 nanoparticles at a dosage of 7.0 mg/kg and euthanized 1, 3, 14, 28, 56, or 90 days after exposure. Lung tissues were collected and evaluated for the expression of proteins associated with inflammation and cellular apoptosis. RESULTS: No change in lung weight was detected over the course of the study; however, cerium accumulation in the lungs, gross histological changes, an increased Bax to Bcl-2 ratio, elevated cleaved caspase-3 protein levels, increased phosphorylation of p38 MAPK, and diminished phosphorylation of ERK-1/2-MAPK were detected after CeO2 instillation (p<0.05). CONCLUSIONS: Taken together, these data suggest that high-dose respiratory exposure to CeO2 nanoparticles is associated with lung inflammation, the activation of signaling protein kinases, and cellular apoptosis, which may be indicative of a long-term localized inflammatory response.
Animals ; Apoptosis/*drug effects ; Caspase 3/metabolism ; Cerium/chemistry ; Inflammation ; Lung/*drug effects/metabolism/pathology ; Male ; Metal Nanoparticles/chemistry/*toxicity ; Mitogen-Activated Protein Kinase 1/metabolism ; Mitogen-Activated Protein Kinase 3/metabolism ; Mitogen-Activated Protein Kinases/*metabolism ; Phosphorylation/drug effects ; Proto-Oncogene Proteins c-bcl-2/metabolism ; Rats ; Rats, Sprague-Dawley ; Signal Transduction/*drug effects ; bcl-2-Associated X Protein/metabolism ; p38 Mitogen-Activated Protein Kinases/metabolism

Objective: The mandible is the most common fractured craniofacial bone of all craniofacial fractures in the Philippines, with the mandibular body as the most involved segment of all mandibular fractures. To the best of our knowledge, there are no existing guidelines for the diagnosis and management of mandibular body fractures in particular. General guidelines include the American Academy of Otolaryngology – Head and Neck Surgery Foundation (AAOHNSF) Resident Manual of Trauma to the Face, Head, and Neck chapter on Mandibular Trauma, the American Association of Oral and Maxillofacial Surgeons (AAOMS) Clinical Practice Guidelines for Oral and Maxillofacial Surgery section on the Mandibular Angle, Body, and Ramus, and a 2013 Cochrane Systematic Review on interventions for the management of mandibular fractures. On the other hand, a very specific Clinical Practice Guideline on the Management of Unilateral Condylar Fracture of the Mandible was published by the Ministry of Health Malaysia in 2005. Addressing the prevalence of mandibular body fractures, and dearth of specific guidelines for its diagnosis and management, this clinical practice guideline focuses on the management of isolated mandibular body fractures in adults. Purpose: This guideline is meant for all clinicians (otolaryngologists – head and neck surgeons, as well as primary care and specialist physicians, nurses and nurse practitioners, midwives and community health workers, dentists, and emergency first-responders) who may provide care to adults aged 18 years and above that may present with an acute history and physical and/or laboratory examination findings that may lead to a diagnosis of isolated mandibular body fracture and its subsequent medical and surgical management, including health promotion and disease prevention. It is applicable in any setting (including urban and rural primary-care, community centers, treatment units, hospital emergency rooms, operating rooms) in which adults with isolated mandibular body fractures would be identified, diagnosed, or managed. Outcomes are functional resolution of isolated mandibular body fractures; achieving premorbid form; avoiding use of context-inappropriate diagnostics and therapeutics; minimizing use of ineffective interventions; avoiding co-morbid infections, conditions, complications and adverse events; minimizing cost; maximizing health-related quality of life of individuals with isolated mandibular body fracture; increasing patient satisfaction; and preventing recurrence in patients and occurrence in others. Action Statements The guideline development group made strong recommendationsfor the following key action statements: (6) pain management- clinicians should routinely evaluate pain in patients with isolated mandibular body fractures using a numerical rating scale (NRS) or visual analog scale (VAS); analgesics should be routinely offered to patients with a numerical rating pain scale score or VAS of at least 4/10 (paracetamol and a mild opioid with or without an adjuvant analgesic) until the numerical rating pain scale score or VAS is 3/10 at most; (7) antibiotics- prophylactic antibiotics should be given to adult patients with isolated mandibular body fractures with concomitant mucosal or skin opening with or without direct visualization of bone fragments; penicillin is the drug of choice while clindamycin may be used as an alternative; and (14) prevention- clinicians should advocate for compliance with road traffic safety laws (speed limit, anti-drunk driving, seatbelt and helmet use) for the prevention of motor vehicle, cycling and pedestrian accidents and maxillofacial injuries.The guideline development group made recommendations for the following key action statements: (1) history, clinical presentation, and diagnosis - clinicians should consider a presumptive diagnosis of mandibular fracture in adults presenting with a history of traumatic injury to the jaw plus a positive tongue blade test, and any of the following: malocclusion, trismus, tenderness on jaw closure and broken tooth; (2) panoramic x-ray - clinicians may request for panoramic x-ray as the initial imaging tool in evaluating patients with a presumptive clinical diagnosis; (3) radiographs - where panoramic radiography is not available, clinicians may recommend plain mandibular radiography; (4) computed tomography - if available, non-contrast facial CT Scan may be obtained; (5) immobilization - fractures should be temporarily immobilized/splinted with a figure-of-eight bandage until definitive surgical management can be performed or while initiating transport during emergency situations; (8) anesthesia - nasotracheal intubation is the preferred route of anesthesia; in the presence of contraindications, submental intubation or tracheostomy may be performed; (9) observation - with a soft diet may serve as management for favorable isolated nondisplaced and nonmobile mandibular body fractures with unchanged pre - traumatic occlusion; (10) closed reduction - with immobilization by maxillomandibular fixation for 4-6 weeks may be considered for minimally displaced favorable isolated mandibular body fractures with stable dentition, good nutrition and willingness to comply with post-procedure care that may affect oral hygiene, diet modifications, appearance, oral health and functional concerns (eating, swallowing and speech); (11) open reduction with transosseous wiring - with MMF is an option for isolated displaced unfavorable and unstable mandibular body fracture patients who cannot afford or avail of titanium plates; (12) open reduction with titanium plates - ORIF using titanium plates and screws should be performed in isolated displaced unfavorable and unstable mandibular body fracture; (13) maxillomandibular fixation - intraoperative MMF may not be routinely needed prior to reduction and internal fixation; and (15) promotion - clinicians should play a positive role in the prevention of interpersonal and collective violence as well as the settings in which violence occurs in order to avoid injuries in general and mandibular fractures in particular.
Mandibular Fractures ; Jaw Fractures ; Classification ; History ; Diagnosis ; Diagnostic Imaging ; Therapeutics ; Diet Therapy ; Drug Therapy ; Rehabilitation ; General Surgery