Staphylococcus aureus proteases trigger eosinophil-mediated skin inflammation

Staphylococcus aureus skin colonization and eosinophil infiltration are associated with many inflammatory skin disorders, including atopic dermatitis, bullous pemphigoid, Netherton's syndrome, and prurigo nodularis. However, whether there is a relationship between S. aureus and eosinophils and how this interaction influences skin inflammation is largely undefined. We show in a preclinical mouse model that S. aureus epicutaneous exposure induced eosinophil-recruiting chemokines and eosinophil infiltration into the skin. Remarkably, we found that eosinophils had a comparable contribution to the skin inflammation as T cells, in a manner dependent on eosinophil-derived IL-17A and IL-17F production. Importantly, IL-36R signaling induced CCL7-mediated eosinophil recruitment to the inflamed skin. Last, S. aureus proteases induced IL-36α expression in keratinocytes, which promoted infiltration of IL-17-producing eosinophils. Collectively, we uncovered a mechanism for S. aureus proteases to trigger eosinophil-mediated skin inflammation, which has implications in the pathogenesis of inflammatory skin diseases.

Hydroxyapatite cement in craniofacial trauma surgery: indications and early experience

BACKGROUND AND OBJECTIVES

Reconstruction of the nonstress-bearing portions of the craniofacial skeleton has recently utilized several alloplastic compounds. One such recent compound is hydroxyapatite cement (HAC)--a calcium-phosphate-based product. Its chemical structure consists primarily of calcium phosphate, as does human bone, and this similarity in the mineral structure renders it biocompatible.

METHODS AND MATERIALS

Based on clinical indications for HAC, the authors have classified acquired craniofacial defects into four types. This article presents 5 clinical cases with craniofacial fractures, sustained in various accidents, in which hydroxyapatite cement was used to prevent cranial deformities or to reinstate contour.

RESULTS AND/OR CONCLUSIONS

Complications were encountered in some of these cases, but all patients healed without any secondary complications. While the short-term experience using hydroxyapatite cement in craniofacial trauma surgery has been favorable, long-term studies in humans are required to validate the safety and efficacy of this product.

The use of osseointegrated implants in craniofacial trauma

The objective in treating patients with injuries sustained in craniofacial trauma is to reinstate preinjury facial projection and function. The capability of providing spatially related facial reconstruction is predicated on basic craniofacial surgical principles, generally accepted as the standard of care. These principles include early surgical intervention, immediate bone grafting, and the use of internal rigid fixation. The introduction of osseointegrated dental implants has significantly improved the overall reconstruction of patients with cranio-maxillofacial injuries, including soft tissue repair and cosmetic surgery. The purpose of this article is to review the utilization of dental implants in the context of maxillofacial trauma, using three cases to document the clinical procedure.

Management of frontal sinus fractures

Frontal sinus fractures have been reported in 2 to 12 percent of all cranial fractures and, according to one study, in 8 percent of all facial fractures. Although immediate frontal bone reconstruction is not universally accepted, it is rapidly becoming the standard of care in treating cranial facial fractures, even in the face of gross contamination. This article presents a historical overview of fracture management, a review of the relevant anatomy, and a discussion of appropriate management principles. Three case studies are presented to demonstrate appropriate techniques for the management of frontal sinus fractures.

Reconstruction of the temporomandibular joint with cryopreserved cartilage and freeze-dried dura: a preliminary report

A technique for total reconstruction of the temporomandibular joint using cryopreserved cartilage and freeze-dried dura is described. The rationale, indications, and surgical technique are discussed. The technique has been used in nine joints in seven patients, followed between 3 and 27 months. There was one total failure of the graft, with the remainder maintaining good, asymptomatic joint function.

Veterans Administration cooperative study on hepatitis and dentistry

Personnel in the VA dental facilities were screened for the detection of viral hepatitis and identification of factors implicating infectivity. A total of 963 personnel from 126 dental facilities throughout the United States voluntarily participated in the study. The rate of seroconversion for any hepatitis B markers was approximately 1% per year. Serial positive tests for antibody to hepatitis B core antigen or antibody to hepatitis B surface antigen (or both) were present in 16.2% of dentists and 13.0% of dental auxiliary personnel. Oral and maxillofacial surgeons composed the highest prevalence occupation (24.0%), and clinical personnel composed the lowest prevalence occupation (8.9%). There was a significant association between years in dental environment and serological positivity for viral B infection. The dentists and dental auxiliary personnel had significant linear trends of increasing serological positivity with years in the dental environment. Although a majority of personnel reported wearing gloves while treating high-risk patients or performing invasive procedures, inadequate prophylactic measures were exercised for most patients undergoing a variety of less invasive procedures. The results of the study show the need for an active immunization program against type B viral infection for dental and dental auxiliary personnel, preferably before the initial exposure to the professional environment.

Prevention of osteoradionecrosis: a randomized prospective clinical trial of hyperbaric oxygen versus penicillin

A prospective randomized trial comparing hyperbaric oxygen and systemic antibiotics in the prevention of osteoradionecrosis was presented. The results indicated, in a high-risk population who required tooth removal in irradiated mandibles, that up-front hyperbaric oxygen produced an incidence of osteoradionecrosis of 5.4% as compared with the antibiotic group of 29.9% (P = .005). Hyperbaric oxygen should be considered a prophylactic measure when post-irradiation dental care involving trauma to tissue is necessary.

Reconstruction of osseous defects with freeze-dried allogeneic and autogenous bone. Clinical and histologic assessment

Freeze-dried allogeneic bone combined with autogenous particulate cancellous bone and marrow was used for reconstruction in 56 patients. With the exception of 3 patients who had infection postoperatively, the patients had complete acceptance of the composite graft system. Histologic examination at 2, 3, 12, 18, and 24 months demonstrated early incorporation, revascularization, resorption of the freeze-dried component, and formation of a bone ossicle that continued to remodel and form mature lamellar bone. This study suggests that freeze-dried allogeneic bone can serve as a latticework along which osteocompetent cells can proliferate, that composite grafts are readily accepted and will form a satisfactory and predictable bone ossicle over a considerable defect, and that freeze-dried allogeneic bone induces the host mesenchymal cells to differentiate into mature osteoblasts and aids in the formation of a long-lasting functional bone graft.

The use of freeze-dried allogeneic bone in oral and maxillofacial surgery

Clinical experience with 36 cases using freeze-dried allogeneic bone is reported. Its use in a variety of surgeries, including ridge augmentation, mandibular and maxillary osteotomies, mandibular reconstruction, midfacial advancement and obliteration of cystic cavities was associated with a minimal incidence of complications and excellent host acceptance. The collection of bone under sterile conditions and the rigid criteria for the tissue banking process are shown to account for this host compatibility and low complication rate. The physiochemical and biologic properties of freeze-dried allogeneic bone are discussed. This material provides unique practical advantages leading to long-term stability.

Cellular survival of human marrow during placement of marrow-cancellous bone grafts

The survival of human marrow cells during the placement of marrow-cancellous bone grafts was studied by three independent viability assays. Marrow cells are resistant cells able to survive the surgical harvest from the ilium. Salt solutions such as normal saline solution and 5% dextrose in water (D5W) were superior to tissue culture medium, the serum of the patients, and several other solutions in supporting the survival of the graft cells. High survival rates of marrow cells stored in normal saline solution and D5W for four hours or less established that 95% to 100% live cells can be transplanted even with long delays between harvest and placement of the graft.

Electrical testing for injuries of the seventh nerve

Electrodiagnostic testing can be used to determine the extent of injury to peripheral nerves. assessment of the function of the nerves after injury is essential for determination of the prognosis and for treatment.

Anatomy related to intubation and general anesthesia

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