Tidal breathing analysis as a tool for asthma diagnosis in children aged six months to five years

@#<p style="text-align: justify;"><strong>BACKGROUND:</strong> The diagnosis of asthma is difficult to establish using spirometry in children below 5 years old. Tidal breathing analysis (TBA) can provide useful information about lung function in infants and young children, as it is effort-independent. </p><p style="text-align: justify;"><strong>OBJECTIVES:</strong> To determine if baseline and post-bronchodilator ratios of the time and volume until peak expiratory flow to the total expiratory time and volume, (tPEF/tE and V PEF/V E) can distinguish asthmatics from normal children.</p><p style="text-align: justify;"><strong>METHODS:</strong> This is a cross-sectional study wherein 146 children ages 6 months to 5 years old completed TBA before and 15 minutes after administration of 250?g of salbutamol via nebulization. Children 3 years old and below who did not cooperate were given sedation with oral diphenhydramine (1mg/kg/dose). The tPEF/tE and VPEF/VE were compared between the controls and asthmatics.</p><p style="text-align: justify;"><strong>RESULTS:</strong> In children below 2 years old, the baseline tPEF/tE of asthmatics and non-asthmatics were 29.6  ± 13.8and 22.0 ± 6.6. The area under the curve (AUC) was 0.649 attPEF/tEof 32.250, with a sensitivity and specificity of 50% and 97%. The baseline VPEF/VE of asthmatics and non-asthmatics were 32.7 ±12.4 and 26.0 ± 4.9.AUC was 0.661 at VPEF/VEof34.500, with a sensitivity and specificity of 50% and 97%.In subjects 2 to 5 years old, the baseline tPEF/tE of asthmatics and non-asthmatics were 35.3 ± 14.7 and 35.0 ± 13.1. The baseline VPEF/VE were 37.0 ± 12.3 and 36.7 ± 10.7. After salbutamol nebulization, the tPEF/tE of asthmatics and non-asthmatics in all ages were 30.9±13.7 and 27.9± 10.8. The VPEF/VE were 34.1± 11.4 and 30.9± 9.0.</p><p style="text-align: justify;"><strong>CONCLUSION</strong>: Baseline tPEF/tE and VPEF/VE can distinguish asthmatics from non-asthmatics in children below 2 years old. However, baseline tPEF/tE and VPEF/VE in children 2 to 5 years old and post-bronchodilator tPEF/tE and VPEF/VE in all ages could not distinguish asthmatics from non-asthmatics after nebulization with 250?g of salbutamol.</p>

Inactivation of TPEF Gene by Aberrant Methylation in Hepatocellular Carcinoma

BACKGROUND: Abnormalities of genomic methylation patterns have been shown to play a role in the development of carcinoma, and the silencing of tumor suppressor genes is related to local de novo methylation. METHODS: Using methylation specific arbitrarily primed-Polymerase Chain Reaction (Ms AP-PCR), we identified a 322 bp sequence that contained a 5' un-translated and exon1 regions of the TPEF gene. To evaluate the inactivation of the TPEF gene through hypermethylation in hepatocellular carcinoma (HCC), we investigated the correlation between methylation patterns and TPEF expression in tumor tissues of human HCC and cell lines via a Combined Bisulfite Restriction Assay (CoBRA) and RT-PCR. RESULTS: A dense methylation pattern of the TPEF was detected in most cell lines, as well as in 10 of the 14 (71.4%) HCC tissues. In addition, loss of heterozygosity (LOH) from the TPEF gene was observed in 5 of the 14 (36%) HCC tissues. Furthermore, RT-PCR analysis revealed TPEF expression in 5 of 8 (62.5%) cell lines. Finally, treatment with a demethylating agent, 5-Aza- 2'-deoxycitidine (5-AzaC), increased the expression of TPEF mRNA. CONCLUSION: These results indicate that inactivation of the TPEF gene through hypermethylation may be a mechanism by which tumorigenesis occurs in HCC.