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Background: Chromosomal Comparative Genomic Hybridization (CGH) has been applied to all stages of cervical carcinoma progression, defining a specific pattern of chromosomal imbalances in this tumor. However, given its limited spatial resolution, chromosomal CGH has offered only general information regarding the possible genetic targets of DNA copy number changes.

Abstract. Fluorescence photobleaching was employed to examine the intercellular movement of fluorescein and carboxyfluorescein between contiguous soybean root cells (SB-1 cell line) growing in tissue culture.

Background: The aetiological relationship between human papillomavirus (HPV) infection and cervical cancer (CC) is widely accepted. Our goal was to determine the prevalence of HPV types in Mexican women attending at the Mexican Institute for Social Security from different areas of Mexico. Materials and Methods: DNAs from 2,956 cervical samples were subjected to HPV genotyping: 1,020 samples with normal cytology, 931 with low-grade squamous intraepithelial lesions (LGSIL), 481 with high grade HGSIL and 524 CC. Results: Overall HPV prevalence was 67.1%. A total of 40 HPV types were found; HPV16 was detected in 39.4% of the HPV-positive samples followed by HPV18 at 7.5%, HPV31 at 7.1%, HPV59 at 4.9%, and HPV58 at 3.2%. HPV16 presented the highest prevalence both in women with altered or normal cytology and HPV 18 presented a minor prevalence as reported worldwide. The prevalence ratio (PR) was calculated for the HPV types. The analysis of PR showed that HPV16 presents the highest association with CC, HPV 31, -33, -45, -52 and -58 also demonstrating a high association. Conclusions: The most prevalent HPV types in cervical cancer samples were -16, -18, -31, but it is important to note that we obtained a minor prevalence of HPV18 as reported worldwide, and that HPV58 and -52 also were genotypes with an important prevalence in CC samples. Determination of HPV genotypes is very important in order to evaluate the impact of vaccine introduction and future cervical cancer prevention strategies.

A light-controlled reversible binding switch based on photochromic 3H-naphtho [2,1-b]pyran is under development for studying cellular oscillatory calcium signals. The binding affinities of the closed and open forms of substituted naphthopyran 1 for Ca 2+ , Mg 2+ , and Sr 2+ in buffer were determined. The photochemically ring-opened form of the receptor exhibited increased affinity compared to the thermally stable closed form of the receptor. The binding affinity difference for Ca 2+ was ∼77-fold at pH 7.6. Calcium (Ca 2+ ) is a second messenger in many cell types, where it is used to translate extracellular signals into a wide variety of intracellular events. 1 Important cellular processes are controlled by Ca 2+ , and many disease states are associated with defects in the calcium signalosome. Manipulation of Ca 2+ concentration in cells through cage compounds is an important tool for learning about this widespread signaling system. 2 Caged Ca 2+ compounds undergo irreversible photochemical reactions that either release or take up Ca 2+ when triggered. However, cage compounds are less well suited to the examination of oscillatory calcium signals, which may encode information through both amplitude and frequency modulation. The origin of these oscillatory signals is known, but their effects at a molecular level are less well understood. There is a need to develop new methodologies to study the effects of spatiotemporal changes in Ca 2+ concentration. In the present work, we report the synthesis and characterization of compound 1, a new watersoluble 3H-naphtho[2,1-b]pyran with an iminodiacetic acid substituent at position 5 ( Figure 1). This compound is designed so that the open form of 1 will exhibit a higher affinity for Ca 2+ than the closed form. The binding affinities of closed and open forms of compound 1 were determined, and the effects of buffer composition and pH, on this reversible calcium binding photoswitch were also examined.Naphthopyran chelator 1 was obtained in five steps (Scheme 1 and Supporting Information) with an overall yield of 11%. Compound 1 is soluble up to ∼5.7 × 10 -4 M in aqueous solutions buffered at pH 8.7.Complexation of the closed form of 1 with metal ions was examined spectroscopically. The UV-vis spectra of 1 show minimal changes upon addition of excess Mg 2+ , Ca 2+ , and Sr 2+ ( Figure S1, Supporting Information). The addition of metal ions to the closed form of 1 did not result in any detectable thermal ring opening induced by metal complexation, unlike that observed for some photochromic chelators. 5d,7d,8 Small but significant and reproducible 1 H NMR shifts were observed upon addition of metal ions (Table S2, Supporting Information). One or more aromatic protons moved downfield upon addition of all metals to the closed form of 1. The methylene protons only shifted when calcium was added, and they moved upfield. The same pattern of complexation-induced shifting, but with smaller magnitudes, was also observed upon the addition of the same three metals to phenyliminodi...

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