Paraffin-embedded tissue as a source of RNA for gene expression analysis in oral malignancy

OBJECTIVE: To assess the feasibility of using archival oral mucosal tissue to examine gene expression at the ribonucleic acid (RNA) level.
MATERIALS AND METHODS: We describe the isolation of RNA from 8 nm sections of formalin-fixed paraffin-embedded oral mucosal tissue. RNA was reverse transcribed and three candidate genes amplified by polymerase chain reaction (PCR). The ribosomal protein S14 gene is a housekeeping gene which has been used as an internal standard in several quantitative PCR protocols. The thymidine kinase (TK) gene is expressed at low levels in most tissues and, with a well-documented genomic organisation, is a useful tool for discrimination between genomic DNA and cDNA. The RIa gene is reported to be overexpressed in many cancer cell lines, in malignant tissue and in vitro transformed cellS. RESULTS: The S14 gene, the TK gene and the RIα gene of the cAMP-dependent protein kinase (PKA) were amplified successfully from formalin-fixed paraffin-embedded tissue sections. The TK primer pair is a useful additional tool in the unambiguous identification of RNA-derived species.
CONCLUSION: RNA suitable for reverse transcribed (RT)-PCR was extracted from archival oral mucosal tissue. This should permit rapid sequence analysis of transcribed tumor suppressor genes and oncogenes in this material. Furthermore, the RT-PCR approach described may allow quantification of gene expression in oral mucosal archival material processed in a standard fashion.     

Aetiological factors for oral manifestations of HIV

OBJECTIVES: Describe the oral diseases in HIV-infected individuals in London, UK and identify social and medical factors related to the presence of specific oral diseases.
DESIGN: Cross-sectional analytic study.
SETTING: Dental clinics.
SUBJECTS: Consecutive sample of 456 patients with HIV infection.
METHODS: Social and medical history and clinical examinations. Univariate and logistic regression analysis.
OUTCOMES: Presence of HIV-associated oral disease.
RESULTS: 80% of patients with AIDS and 50% of patients with HIV had a specific oral disease. The most common diseases were hairy leukoplakia (30%), erythematous candidiasis (24%), pseudomembranous candidiasis (14%), angular chielitis (6%), necrotising periodontal disease (8%) and non-recurrent ulceration (6%).
CONCLUSIONS: The presence of erythematous candidiasis was not related to advanced HIV disease. Pseudomembranous candidiasis, hairy leukoplakia and mucosal ulceration were significantly associated with advanced HIV disease. Smoking was also identified as a strong aetiological factor in oral diseases. Longitudinal studies are required to further explore the prognostic significance of oral diseases in HIV infection.     

Cost-effectiveness of screening with B-type natriuretic peptide to identify patients with reduced left ventricular ejection fraction

OBJECTIVES: This study was designed to evaluate the cost-effectiveness of screening patients with a B-type natriuretic peptide (BNP) blood test to identify those with depressed left ventricular systolic function. BACKGROUND: Asymptomatic patients with depressed ejection fraction (EF) may have less progression to heart failure if they can be identified and treated. METHODS: We used a decision model to estimate economic and health outcomes for different screening strategies using BNP and echocardiography to detect left ventricular EF <40% for men and women age 60 years. We used published data from community cohorts (gender-specific BNP test characteristics, prevalence of depressed EF) and randomized trials (benefit from treatment). RESULTS: Screening 1,000 asymptomatic patients with BNP followed by echocardiography in those with an abnormal test increased the lifetime cost of care (176,000 US dollars for men, 101,000 US dollars for women) and improved outcome (7.9 quality-adjusted life years [QALYs] for men, 1.3 QALYs for women), resulting in a cost per QALY of 22,300 US dollars for men and 77,700 US dollars for women. For populations with a prevalence of depressed EF of at least 1%, screening with BNP followed by echocardiography increased outcome at a cost < 50,000 US dollars per QALY gained. Screening would not be attractive if a diagnosis of left ventricular dysfunction led to significant decreases in quality of life or income. CONCLUSIONS: Screening populations with a 1% prevalence of reduced EF (men at age 60 years) with BNP followed by echocardiography should provide a health benefit at a cost that is comparable to or less than other accepted health interventions.