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Background: Alveolar ridge aberrations commonly require bone augmentation procedures for optimal placement of endosseous dental implants. The objective of this study was to evaluate local bone formation following implantation of recombinant human bone morphogenetic protein-2 (rhBMP-2) in an absorbable collagen sponge (ACS) carrier with or without provisions for guided bone regeneration (GBR) as potential treatment modalities for alveolar augmentation. Methods: Surgically induced, large, mandibular alveolar ridge saddle-type defects (2 defects/jaw quadrant) in seven young adult Hound dogs were assigned to receive rhBMP-2/ACS, rhBMP-2/ACS combined with GBR (rhBMP-2/GBR), GBR, and surgery controls. The animals were euthanized at 12 weeks post-surgery when block sections of the defect sites were collected for histologic analysis. Results: Clinical complications included swelling for sites receiving rhBMP-2 and wound failure with exposure of the barrier device for sites receiving GBR (4/6) or rhBMP-2/GBR (3/7). The radiographic evaluation showed substantial bone fill for sites receiving rhBMP-2/ACS, rhBMP-2/GBR, and GBR. In particular, sites receiving rhBMP-2/GBR presented with seroma-like radiolucencies. The surgery control exhibited moderate bone fill. To evaluate the biologic potential of the specific protocols, sites exhibiting wound failure were excluded from the histometric analysis. Sites receiving rhBMP-2/ACS or rhBMP-2/GBR exhibited bone fill averaging 101%. Bone fill averaged 92% and 60%, respectively, for sites receiving GBR and surgery controls. Bone density ranged from 50% to 57% for sites receiving rhBMP-2/ACS, GBR, or surgery controls. Bone density for sites receiving rhBMP-2/GBR averaged 34% largely due to seroma formation encompassing 13% to 97% of the sites. Conclusion: rhBMP-2/ACS appears to be an effective alternative to GBR in the reconstruction of advanced alveolar ridge defects. Combining rhBMP-2/ACS with GBR appears to be of limited value due to the potential for wound failure or persistent seromas. [ABSTRACT FROM AUTHOR]

Osseointegration [direct bone–implant contact (BIC)] is a primary goal following installation of endosseous dental implants. Such bone contact provides stability for the dental implant over time. The objective of this study was to evaluate bone formation and BIC at long-term, functionally loaded, endosseous dental implants placed into bone induced by recombinant human bone morphogenetic protein-2 (rhBMP-2) in an absorbable collagen sponge (ACS) carrier. Mandibular, saddle-type, alveolar ridge defects (∼15 × 10 × 10 mm), two per jaw quadrant, were surgically induced in each of six young adult American fox hounds. The defects were immediately implanted with rhBMP-2/ACS. Two defects per animal additionally received a nonresorbable expanded polytetrafluoroethylene (ePTFE) membrane or a bioresorbable polyglycolide fiber membrane. Healing was allowed to progress for 3 months, when the ePTFE membrane was removed, and machined, threaded, titanium dental implants were installed into the rhBMP-2/ACS induced bone and into the adjacent resident bone. At 4 months of osseointegration, the implants were exposed to receive abutments and prosthetic treatment (two- or three-unit bridges). Some implants were removed for histologic analysis. The remainder of implants were exposed to functional loading for 12 months at which time the animals were killed for histometric analysis. One animal died prematurely due to kidney failure unrelated to the experimental protocol and was not included in the analysis. The 12-month block sections from a second animal were lost in the histological processing. Four sites receiving rhBMP-2/ACS and ePTFE or resorbable membranes experienced wound failure and membrane exposure, and subsequently exhibited limited bone formation. Defects without wound failure filled to contour with the adjacent alveolar bone. The newly formed bone exhibited features of the resident bone with a re-established cortex; however, it commonly included radiolucent areas that resolved over time. Dental implants block biopsied at 4 months exhibited limited, if any, crestal resorption, whereas those exposed to functional loading for 12 months exhibited some crestal resorption. Implants biopsied at 4 months exhibited a mean (± SD) BIC of 40.6 ± 8.2% in rhBMP-2/ACS induced bone vs. 52.7 ± 11.4% in resident bone. Dental implants exposed to 12 months of functional loading exhibited a mean BIC of 51.7 ± 7.1% in rhBMP-2/ACS induced bone vs. 74.7 ± 7.0% in resident bone. There were no significant differences between dental implants placed into rhBMP-2/ACS induced bone and resident bone for any parameter at any observation interval. In conclusion, rhBMP-2/ACS-induced bone allows installation, osseointegration, and long-term functional loading of machined, threaded, titanium dental implants in dogs. [ABSTRACT FROM AUTHOR]

We have tested a hypothesis that the natural product curcuminoids. which has epidemiologic and experimental rationale for use in AD, may improve the innate immune system and increase amyloid-β (Aβ) clearance from the brain of patients with sporadic Alzheimer's disease (AD). Macrophages of a majority of AD patients do not transport Aβinto endosomes and lysosomes. and AD monocytes do not efficiently clear Aβ from the sections of AD brain, although they phagocytize bacteria. In contrast, macrophages of normal subjects transport Aβ to endosomes and lysosomes, and monocytes of these subjects clear Aβ in AD brain sections. Upon Aβ stimulation, mononuclear cells of normal subjects up-regulate the transcription of β-1,4-mannosyl-glycoprotein 4-β-N-acetylglucosaminyltransferase (MGAT3) (P < 0.001) and other genes, including Toll like receptors (TLRs), whereas mononuclear cells of AD patients generally down-regulate these genes. Defective phagocytosis of Aβ may be related to down-regulation of MGAT3, as suggested by inhibition of phagocytosis by using MGAT3 siRNA and correlation analysis. Transcription of TLR3, bditTLR4, TLR5, bditTLR7, TLR8, TLR9, and TLR10 upon Aβ stimulation is severely depressed in mononuclear cells of AD patients in comparison to those of control subjects. In mononuclear cells of some AD patients, the curcuminoid compound bisdemethoxycurcumin may enhance defective phagocytosis of Aβ, the transcription of MGAT3 and TLRs, and the translation of TLR2-4. Thus, bisdemethoxycurcumin may correct immune defects of AD patients and provide a previously uncharacterized approach to AD immunotherapy. [ABSTRACT FROM AUTHOR]

Tissue-engineered grafts for tissue regeneration include either mature or progenitor cells seeded onto biomatrices that provide shape and support for developing tissue. Popular biomaterials used in orthopaedic surgery include collagen type I, hyaluronic acid, hydroxyapatite, and polylactic polyglycolic acid (PLGA). Biomatrices with bacteriostatic properties may be beneficial in promoting tissue-engineered graft survival in patients susceptible to infection. We evaluated the bacteriostatic effects of these biomaterials on the growth of the four most common orthopaedic bacterial pathogens: Staphylococcus aureus, Staphylococcus epidermidis, β-hemolytic Streptococcus, and Pseudomonas aeruginosa. Hyaluronic acid demonstrated the largest bacteriostatic effect on these pathogens by inhibiting bacterial growth by an average of 76.8% (p=0.0005). Hydroxyapatite and collagen inhibited growth on average by 49.7% (p=0.011) and 37.5% (p=0.102), respectively. PLGA exhibited the least bacteriostasis with an average inhibition of 9.8% (NS) and actually accelerated the growth of β-hemolytic Streptococcus and P. aeruginosa. [Copyright &y& Elsevier]

The authors report the case of a 45-year-old woman who presented to our institution with 10 days history of confusion and signs of progressive raised intracranial pressure as a result of a minor head injury occurred 4 weeks before. A brain CT-scan showed a large right hemispheric chronic subdural haematoma which was, as routinely, treated by burr-hole craniostomy and closed-drainage. Although the procedure was uneventful, the next day the patient developed a mild left hemiparesis associated to a slight global status worsening. A brain CT scan showed an intracerebral position of the drain with diffuse brain oedema and midline shift. Following drain removal the patient developed a serious neurological deterioration dropping the Glasgow coma scale to 8/15 as the result of an intracerebral and intraventricular haemorrhage along the removed drain trajectory. The clinical features of this iatrogenic complication are reported analysing also globally chronic subdural haematoma management and discussing pertinent literature.

Background. The authors describe a lateral approach to the cervical spine for the management of spondylotic myeloradiculopathy. The rationale for this approach and surgical technique are discussed, as well as the advantages, disadvantages, complications, and pitfalls based on the author's experience over the last two decades. Methods. Spondylotic myelo-radiculopathy may be treated via a lateral approach to the cervical spine when there is predominant anterior compression associated with either spine straightening or kyphosis, but without vertebral instability. Results. By using a lateral approach, the lateral aspect of the cervical spine and the vertebral artery are easily reached and visualized. Furthermore, the lateral part of the affected intervertebral disc(s), uncovertebral joint(s), vertebral body(ies), and posterior longitudinal ligament can be removed as needed to decompress nerve root(s) and/or the spinal cord. Conclusion. Multilevel cervical oblique corpectomy and/or lateral foraminotomy allow wide decompression of nervous structures, while maintaining optimal stability and physiological motion of the cervical spine.

By testing archival paraffinized biopsy blocks obtained from the oral pathology library with immunohistochemistry, we tested the hypothesis that substantial alterations are demonstrable in the cross-talk between sympathetic (VMAT) and para-sympathetic innervation (VAchT), and resident CD3+ T cells in the mucosa from oral lichen planus (OLP), compared to recurrent aphthous stomatitis (RAS) and control biopsies. We quantified fractal dimension and Euclidean dimension of CD3+ cells between the two pathologies, and across the set of CD3+ cells proximal to the vesicles of monoamines transport (VMAT)+ or the vesicles of acetylcholine transport (VAchT)+ innervation, compared to cells relatively distal to the nerve endings. The data show exquisite organization of the punctuate sympathetic and para-sympathetic staining about the resident CD3+ T cells in the OLP lesions, but not in the aphthous lesions or in control mucosa. Fractal analysis reveals that aphthous lesions are characterized by CD3+ T cells of larger size (Euclidean dimensional map), compared to control mucosa. CD3+ T cells in OLP lesions are also found to be significantly larger than those found in control lesions, when they are not proximal to sympathetic or para-sympathetic vesicles. The membrane of CD3+ T cells is overall more complex (fractal dimension) in aphthous lesions, compared to control sections. A similar trend is apparent, albeit not statistically significant, in CD3+ T cells resident in OLP lesions, whether or not they are located proximal to nerve endings. An overall decrease in the ratio of fractal dimension-over-topological dimension was also observed across the pathological lesions, compared to control. Taken together, these data indicate that as CD3+ T cells grow larger in the pathological conditions, they, in effect, stretch their plasma membrane, and that the cells may be at different stage of the cell cycle, relative to their position vis a' vis nerve endings. Because fractal analysis is performed on individual cells, it has the potential of being developed in a novel diagnostic test, as well as a prognostic tool for monitoring the etiology and the course of treatment at the individual cellular level. Our findings also open new frontiers of fundamental, clinical and translational biosciences of OLP.