Progressive Consent and Specimen Accrual Models to Address Sustainability: A Decade's Experience at an Oregon Biorepository.

Background: The Legacy Biorepository is a College of American Pathologists-accredited biorepository operating within a seven-hospital healthcare system, with a decade's experience in specimen accrual, storage, and distribution. While standardization of our practices through accreditation remains a priority, we along with others face challenges with regard to sustainability. Purposeful changes in our consent process, which we term "progressive consent," are expected to improve sustainability and operational flexibility while increasing our scientific impact.

MicroRNA-21 overexpression contributes to vestibular schwannoma cell proliferation and survival.

Hypothesis: Elevated levels of hsa-microRNA-21 (miR-21) in vestibular schwannomas (VSs) may contribute to tumor growth by downregulating the tumor suppressor phosphatase and tensin homolog (PTEN) and consequent hyperactivation of protein kinase B (AKT), a key signaling protein in the cellular pathways that lead to tumor growth.

Background: Vestibular schwannomas are benign tumors that arise from the vestibular nerve. Left untreated, VSs can result in hearing loss, tinnitus, vestibular dysfunction, trigeminal nerve dysfunction, and can even become life threatening.

Cholesteatoma growth and proliferation: posttranscriptional regulation by microRNA-21.

Objectives: The goal of this study was to identify novel regulatory mechanisms controlling the growth and proliferation of cholesteatoma. Specifically, the potential role of microRNAs, regulators of protein translation, was studied in cholesteatoma.

Study Design: This study represents a molecular biologic investigation characterizing and comparing microRNA and protein expression in cholesteatoma and normal postauricular skin.

Mucin gene 19 (MUC19) expression and response to inflammatory cytokines in middle ear epithelium.

Mucin gene 19 (MUC19) has been identified as a major gel-forming mucin in the human middle ear (ME). The objectives of this investigation were to characterize the expression and assess the regulation of MUC19 in the ME cell culture models utilized in the study of otitis media (OM). Findings demonstrate that MUC19 is expressed in both human immortalized cell culture (HMEEC) and chinchilla primary epithelial culture (CMEEC).

Differential expression of cytoskeletal genes in the cochlear nucleus.

The relationship between structure and function is clearly illustrated by emerging evidence demonstrating the role of the neuronal cytoskeleton in physiological processes. For example, alterations in axonal caliber, a feature of the cytoskeleton, have been shown to affect reflex arc latencies and are prominent features of several neuropathological disorders. Even in the nonpathologic situation, however, axonal diameter may be a crucial element for the normal function of specialized auditory neurons.

Signaling pathways in interleukin-1beta-mediated middle ear mucin secretion.

Objectives: The objectives of this study were to investigate the role of the phosphatidylcholine-specific phospholipase C (PC-PLC), protein kinase C (PKC), and nitric oxide synthase (NOS) pathways during upregulation of mucin secretion by middle ear epithelium after exposure to interleukin-1beta and to examine the ability of a specific interleukin-1 receptor antagonist (IL-1betara) to block this increased secretion.

Materials And Methods: Primary chinchilla middle ear epithelial cultures were established and exposed to IL-1beta. Specific inhibitors of calmodulin, PC-PLC, PKC, and NOS pathways were used to investigate the potential role of these pathways leading to increased epithelial mucin secretion after exposure to IL-1beta.

In silico analysis of 2085 clones from a normalized rat vestibular periphery 3' cDNA library.

The inserts from 2400 cDNA clones isolated from a normalized Rattus norvegicus vestibular periphery cDNA library were sequenced and characterized. The Wackym-Soares vestibular 3' cDNA library was constructed from the saccular and utricular maculae, the ampullae of all three semicircular canals and Scarpa's ganglia containing the somata of the primary afferent neurons, microdissected from 104 male and female rats. The inserts from 2400 randomly selected clones were sequenced from the 5' end.

Molecular characterization of two novel splice variants of G alphai2 in the rat vestibular periphery.

GTP binding proteins play an important role in mediating signals transduced across the cell membrane by membrane-bound receptors. We previously described a partial sequence, termed Galphai2vest, obtained from rat vestibular tissue that was nearly identical to rat Galphai2. Using an experimental strategy to further characterize Galphai2vest (GenBank accession number AF189020) and identify other possible Galphai2-related transcripts expressed in the rat vestibular periphery, we employed a RecA-based gene enrichment protocol in place of conventional library screening techniques.

G-protein Golfalpha (GNAL) is expressed in the vestibular end organs and primary afferent neurons of Rattus norvegicus.

Guanine nucleotide binding proteins (G-proteins) play an important role in mediating signals transduced across the cell membrane by membrane-bound receptors. The precise role of these proteins and their coupled receptors in the physiology of the vestibular neuroepithelium is poorly understood. Although Golfalpha was originally discovered in the olfactory neuroepithelium and striatum, we recently identified this G-protein alpha subunit in a normalized cDNA library constructed from rat vestibular end organs and vestibular nerves including Scarpa's ganglia.

Assessment of differential gene expression in vestibular epithelial cell types using microarray analysis.

Current global gene expression techniques allow the evaluation and comparison of the expression of thousands of genes in a single experiment, providing a tremendous amount of information. However, the data generated by these techniques are context-dependent, and minor differences in the individual biological samples, methodologies for RNA acquisition, amplification, hybridization protocol and gene chip preparation, as well as hardware and analysis software, lead to poor correlation between the results. One of the significant difficulties presently faced is the standardization of the protocols for the meaningful comparison of results.

Selective acquisition of individual cell types in the vestibular periphery for molecular biology studies.

Objectives: To develop a method for characterizing the transcriptome of individual cell types in the inner ear sensory epithelia.

Study Design: We employed the technique of laser capture microdissection to obtain enriched populations of hair cells and supporting cells. The respective mRNAs were extracted, reverse transcribed, and amplified using PCR.

Serial analysis of gene expression in neurofibromatosis type 2-associated vestibular schwannoma.

Hypothesis: The genesis, morphology, and growth characteristics of vestibular schwannomas are determined by genetic alterations which vary gene transcript expression and this transcript expression can be qualitatively and quantitatively evaluated using the SAGE technique. By use of such technique, gene products with tumorigenic potential may be identified, providing insight and targets for future study.

Background: Serial analysis of gene expression (SAGE) is a powerful new technique that allows detailed qualitative and quantitative evaluation of cellular gene transcript expression.

Expression of G-protein alpha subunit genes in the vestibular periphery of Rattus norvegicus and their chromosomal mapping.

Objective: Heterotrimeric G-proteins play an important role in mediating signals transduced across the cell membrane by membrane-bound receptors. The precise role of G-proteins and their coupled receptors in the physiology of the vestibular neuroepithelium is not well understood. The purpose of this study was to better define the role of these proteins by examining their expression in the rat vestibular periphery and characterizing their chromosomal location.