88 research outputs found
Gene expression analysis of immunostained endothelial cells isolated from formaldehyde-fixated paraffin embedded tumors using laser capture microdissectionâA technical report
Laser capture microdissection (LCM) allows microscopic procurement of specific cell types from tissue sections that can then be used for gene expression analysis. In conventional LCM, frozen tissues stained with hematoxylin are normally used to the molecular analysis. Recent studies suggested that it is possible to carry out gene expression analysis of formaldehyde-fixated paraffin embedded (FFPE) tissues that were stained with hematoxylin. However, it is still unclear if quantitative gene expression analyses can be performed from LCM cells from FFPE tissues that were subjected to immunostaining to enhance identification of target cells. In this proof-of-principle study, we analyzed by reverse transcription-PCR (RT-PCR) and real time PCR the expression of genes in factor VIII immunostained human endothelial cells that were dissected from FFPE tissues by LCM. We observed that immunostaining should be performed at 4°C to preserve the mRNA from the cells. The expression of Bcl-2 in the endothelial cells was evaluated by RT-PCR and by real time PCR. Glyceraldehyde-3-phosphate dehydrogenase and 18S were used as house keeping genes for RT-PCR and real time PCR, respectively. This report unveils a method for quantitative gene expression analysis in cells that were identified by immunostaining and retrieved by LCM from FFPE tissues. This method is ideally suited for the analysis of relatively rare cell types within a tissue, and should improve on our ability to perform differential diagnosis of pathologies as compared to conventional LCM. Microsc. Res. Tech., 2009. © 2009 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/64450/1/20734_ftp.pd
Problem Alcohol Use Among Rural Head and Neck Cancer Patients at Diagnosis: Associations with Health-related Quality of Life
OBJECTIVE: Problem alcohol use in persons with head and neck cancer (HNC) is associated with poor outcomes, including survival. Some evidence suggests that individuals living in rural areas may be at greater risk of problem alcohol use. The present exploratory cross-sectional study sought to examine problem alcohol use at diagnosis in a sample of HNC patients by rural vs urban status. METHODS: Self-reported problem alcohol use as measured by the Short Michigan Alcoholism Screening Test (SMAST) was examined in rural and urban HNC patients at diagnosis (N=454). Multivariable linear regression analysis was conducted to examine correlates of problem alcohol use. Subgroup analyses examined HNC-specific health-related quality of life (HRQOL) by problem drinking status at diagnosis and 3- and 12-months postdiagnosis in rural patients. RESULTS: Multivariable linear regression analysis controlling for age, cancer site, cancer stage, depressive symptoms at diagnosis, and tobacco use at diagnosis indicated that rural residence was significantly associated with SMAST scores at diagnosis such that rural patients were more likely to report higher scores (Ă=.095, sr(2)=.010, p=.04). Covariate-adjusted subgroup analyses suggest that rural patients with self-reported problem alcohol use may exhibit deficits in HNC-specific HRQOL at diagnosis and 3- and 12-months postdiagnosis. CONCLUSIONS: HNC patients should be screened for problem alcohol use at diagnosis and counseled regarding the deleterious effects of continued drinking during treatment and beyond. Because access to treatment and referral options may be lacking in rural areas, additional ways of connecting rural patients to specialty care should be explored
Enhancing the antibacterial performance of orthopaedic implant materials by fibre laser surface engineering
Implant failure caused by bacterial infection is extremely difficult to treat and usually requires the removal of the infected components. Despite the severe consequence of bacterial infection, research into bacterial infection of orthopaedic implants is still at an early stage compared to the effort on enhancing osseointegration, wear and corrosion resistance of implant materials. In this study, the effects of laser surface treatment on enhancing the antibacterial properties of commercially pure (CP) Ti (Grade 2), Ti6Al4V (Grade 5) and CoCrMo alloy implant materials were studied and compared for the first time. Laser surface treatment was performed by a continuous wave (CW) fibre laser with a near-infrared wavelength of 1064 nm in a nitrogen-containing environment. Staphylococcus aureus, commonly implicated in infection associated with orthopaedic implants, was used to investigate the antibacterial properties of the laser-treated surfaces. The surface roughness and topography of the laser-treated materials were analysed by a 2D roughness testing and by AFM. The surface morphologies before and after 24 h of bacterial cell culture were captured by SEM, and bacterial viability was determined using live/dead staining. Surface chemistry was analysed by XPS and surface wettability was measured using the sessile drop method. The findings of this study indicated that the laser-treated CP Ti and Ti6Al4V surfaces exhibited a noticeable reduction in bacterial adhesion and possessed a bactericidal effect. Such properties were attributable to the combined effects of reduced hydrophobicity, thicker and stable oxide films and presence of laser-induced nano-features. No similar antibacterial effect was observed in the laser-treated CoCrMo
The new molecular markers DDIT3, STT3A, ARG2 and FAM129A are not useful in diagnosing thyroid follicular tumors
Preoperative characterization of thyroid follicular lesions is challenging. Fine-needle aspiration specimens cannot differentiate follicular carcinomas from benign follicular neoplasias. Recently, promising markers have been detected using modern molecular techniques. We conducted a retrospective study to confirm the usefulness of immunohistochemical staining for the protein markers, DDIT3, STT3A (ITM1), ARG2 and FAM129A (C1orf24) in separating benign and malignant thyroid follicular lesions. Formalin-fixed, paraffin-embedded thyroid tissue from 30 in-house cases (15 follicular carcinomas and 15 follicular adenomas), as well as 8 follicular carcinomas and 21 follicular adenomas on tissue microarray slides were stained immunohistochemically for DDIT3, STT3A, ARG2 and FAM129A expression. Control tissue consisted of thyroid parenchyma adjacent to the tumors and 11 separate cases of normal thyroid parenchyma. All in-house cases of follicular adenomas, follicular carcinomas and adjacent normal thyroid tissue showed positive immunostaining with anti-DDIT3 and anti-STT3A. Anti-ARG2 and anti-FAM129A polyclonal antibodies showed positive staining in 20 and 60% of in-house follicular adenomas, and 40 and 87% of in-house follicular carcinomas, respectively. Monoclonal anti-FAM129A demonstrated positive staining in 13 and 33% of in-house follicular adenomas and follicular carcinomas, respectively. Polyclonal anti-DDIT3, -STT3A and -FAM129A antibodies showed positive staining in all tissue microarray slides of follicular carcinoma and in 76, 85 and 81% of the follicular adenomas, respectively. Monoclonal anti-STT3A stained 81% of the follicular adenoma cores. Anti-ARG2 stained positive in 13% of follicular carcinomas and 10% of follicular adenomas on the tissue microarray slides. In conclusion, DDIT3, STT3A, ARG2 and FAM129A immunohistochemistry does not appear to be useful in the diagnosis of thyroid follicular neoplasias, as they do not reliably distinguish follicular thyroid carcinoma from follicular thyroid adenoma
Antibiofilm Effect of DNase against Single and Mixed Species Biofilm
Biofilms are aggregates of microorganisms that coexist in socially coordinated micro-niche in a self-produced polymeric matrix on pre-conditioned surfaces. The biofilm matrix reduces the efficacy of antibiofilm strategies. DNase degrades the extracellular DNA (e-DNA) present in the matrix, rendering the matrix weak and susceptible to antimicrobials. In the current study, the effect of DNase I was evaluated during biofilm formation (pre-treatment), on preformed biofilms (post-treatment) and both (dual treatment). The DNase I pre-treatment was optimized for P. aeruginosa PAO1 (model biofilm organism) at 10 ”g/mL and post-treatment at 10 ”g/mL with 15 min of contact duration. Inclusion of Mg2+ alongside DNase I post-treatment resulted in 90% reduction in biofilm within only 5 min of contact time (irrespective of age of biofilm). On extension of these findings, DNase I was found to be less effective against mixed species biofilm than individual biofilms. DNase I can be used as potent antibiofilm agent and with further optimization can be effectively used for biofilm prevention and reduction in situ
Examination of risk factors for discontinuation of followâup care in patients with head and neck cancer
Abstract Background Little research has examined discontinuation of followâup care in patients with head and neck cancer. This exploratory study sought to examine key demographic, disease, and behavioral factors as possible correlates of discontinuation (N = 512). Methods Crossâsectional study examined correlates of discontinuation of followâup care within 1âyear. The primary outcome was defined as a diseaseâfree survivor not returning to cancer clinic for two consecutive followâup appointments within the first year of care and not reentering oncologic care at any point thereafter. Demographic, disease, and behavioral factors were examined using multivariable logistic regression. Results One hundred twentyâsix (24.6%) patients discontinued by 12âmonth followâup. Being unmarried (OR = 1.28, 95% CI = 1.01â1.63, p = 0.041) and having elevated depressive symptomatology (OR = 1.04, 95% CI = 1.01â1.07, p = 0.034) were significantly associated with discontinuation. Receipt of a single (vs. multimodal) treatment approached significance (OR = 1.71, 95% CI = 0.96â3.07, p = 0.071). Conclusion Approximately one quarter of patients disengaged from important followâup care within 1âyear. Lack of social support, depressive symptomatology, and single treatment modality may be important correlates of discontinuation of care in patients with head and neck cancer. Additional studies of this outcome are needed. Improved understanding of correlates associated with discontinuation could facilitate the identification of atârisk patients and further development of interventions to keep patients engaged at a crucial time in the survivorship care trajectory
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