Solitary Bone Cyst of the Jaws: A Review of the Etiopathogenic Hypotheses

Solitary bone cysts (SBCs) of the jaws are often polymorphic, show scalloped borders when located between the teeth roots, are devoid of an epithelial lining, and are usually empty or contain blood or a straw-colored fluid. The numerous synonyms referring to these lesions reflect their uncertain nature (eg, traumatic bone cyst, simple bone cyst). SBC, also found in other skeletal locations, is often suspected after epidemiologic and radiologic test results and confirmed at surgery. Histology usually shows fibrous connective tissue or only bone. The various etiologic elements responsible for SBC include tumor degeneration, trauma, or abnormalities during bone growth. The pathogenesis of the SBC is unknown, but it is widely accepted that it could be the result of a vascular dysfunction leading to a local posthemorrhagic ischemia, inducing an osseous aseptic necrosis. This article reviews likely but still-debated etiopathogenic hypotheses of lesions of the jaws and other, more frequent bony locations, such as the humeral and femoral metaphysis

The cerebrospinal fluid neurogranin/BACE1 ratio is a potential correlate of cognitive decline in Alzheimers disease

Background: In diagnosing Alzheimer’s disease (AD), ratios of cerebrospinal fluid (CSF) biomarkers, such as CSF Aβ(1-42)/tau, have an improved diagnostic performance compared to the single analytes, yet, still a limited value to predict cognitive decline. Since synaptic dysfunction/loss is closely linked to cognitive impairment, synaptic proteins are investigated as candidate CSF AD progression markers. Objective: We studied CSF levels of the postsynaptic protein neurogranin and protein BACE1, predominantly localized presynaptically, and their relation to CSF total-tau, Aβ(1-42), Aβ(1-40), and Aβ(1-38). All six analytes were considered as single parameters as well as ratios. Methods: Every ELISA involved was based on monoclonal antibodies, including the BACE1 and neurogranin immunoassay. The latter specifically targets neurogranin C-terminally truncated at P75, a more abundant species of the protein in CSF. We studied patients with MCI due to AD (n = 38) and 50 dementia due to AD patients, as well as age-matched cognitively healthy elderly (n = 20). A significant subset of the patients was followed up by clinical and neuropsychologically (MMSE) examinations for at least one year. Results: The single analytes showed statistically significant differences between the clinical groups, but the ratios of analytes indeed had a higher diagnostic performance. Furthermore, only the ratio of CSF neurogranin trunc P75/BACE1 was significantly correlated with the yearly decline in MMSE scores in patients with MCI and dementia due to AD, pointing toward the prognostic value of the ratio. Conclusion: This is the first study demonstrating that the CSF neurogranin trunc P75/BACE1 ratio, reflecting postsynaptic/presynaptic integrity, is related to cognitive decline