Mutation analysis of the DBC2 gene in sporadic and familial breast cancer.

The expression of the recently identified tumor suppressor gene, DBC2 (Deleted in Breast Cancer 2), is frequently extinguished in breast cancer cells or tissues. Mutation analysis of the essential promoter region, all exons and exon/intron boundaries of the DBC2 gene was performed in 100 sporadic breast cancer cases by PCR-SSCP, and DHPLC, followed by direct sequencing. An additional 17 breast cancer families, who were negative for the BRCA1/2 mutations, were analyzed by direct sequencing. Three novel mutations were observed in the promoter and 5'-untranslated region (UTR) of the gene; a germ-line G>A transition in the promoter at nt -238 from the transcription start site, and two tumor-specific mutations at nt -121C>T and nt +48G>A. No deleterious mutations were detected in the coding sequence of the gene in familial and sporadic breast cancer cases. The sequence variations found within the promoter and 5'-UTR region of the gene warrant expression analysis and screening more tumor samples at this region.

The prevalence of domestic violence against pregnant women in Perak, Malaysia.

Domestic violence during pregnancy is a key issue in maternal and fetal mortality and morbidity. This cross-sectional study aimed at obtaining the prevalence of domestic violence amongst pregnant women who attended Ipoh General Hospital in Perak, Malaysia and to determine the risk factors associated with domestic violence during pregnancy. The prevalence of domestic violence was low (4.5%). Comparison between the two groups of subjects with or without domestic violence did not show any significant difference in terms of risk factors. The effect of domestic violence on pregnancy should be investigated comprehensively in a multicentral or community-based study using a culturally sensitive questionnaire. With the estimated low prevalence of domestic violence in this study, the need for screening it in health-care services in Malaysia is yet to be determined.

Hall effect in the normal phase of the organic superconductor (TMTSF)2PF6

We report accurate Hall effect measurements performed in the normal phase of the quasi-one-dimensional organic conductor (TMTSF)2PF6 at ambient pressure. The Hall coefficient is found to be strongly temperature dependent all the way from 300 K down to the spin density wave onset arising around 12 K. These new results emphasize the existence of a high temperature regime above 130 K where the Fermi liquid model is not satisfactory.

Charge transport along the lambda-DNA double helix.

We have measured the conductivity sigma along the lambda phage DNA (lambda-DNA) double helix at microwave frequencies using lyophilized DNA in and also without a buffer. The conductivity is strongly temperature dependent around room temperature with a crossover to a weakly temperature dependent conductivity at low temperatures. Removal of the water mantle around the double helix leads to reduced conductivity.

Charge ordering in the TMTTF family of molecular conductors

Using one- and two-dimensional NMR spectroscopy applied to 13C spin-labeled (TMTTF)2AsF6 and (TMTTF)2PF6, we demonstrate the existence of an intermediate charge-ordered phase in the TMTTF family of charge-transfer salts. At ambient temperature, the spectra are characteristic of nuclei in equivalent molecules. Below a continuous charge-ordering transition temperature T(co), there is evidence for two inequivalent molecules with unequal electron densities. The absence of an associated magnetic anomaly indicates only the charge degrees of freedom are involved and the lack of evidence for a structural anomaly suggests that charge-lattice coupling is too weak to drive the transition.