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1.
Summary This paper describes the microscopic evidence supporting a cesium-induced delay in the fusion of chick embryo myoblast membranes during in vitro myogenic differentiation. We have recently demonstrated that the sharp decrease in the conductivity and permittivity of the membranes of these myogenic cells at the time of fusion is delayed 30 h by the addition of cesium to the culture medium (Santini et al., Biochim. Biophys. Acta 945:56–64; 1988). We report here that this delay in fusion is substantiated by direct microscopic observation and that cesium also induces ultrastructural changes in the myoblast cells themselves. Possible mechanisms by which cesium may cause both the delay in fusion as well as the ultrastructural changes observed are discussed. This investigation was partially supported by an Italian Consiglio Nazionale delle Ricerche grant 85.00.304.02 (to P. L. I.).  相似文献   
2.
Papillomavirus-like particles (VLPs) based on L1 capsid protein represent a promising prophylactic vaccine against human papillomavirus (HPV) infections. However, cell-mediated immune responses against this antigen are believed to be of limited therapeutic value in established HPV-infected cervical lesions and, for this reason, have not been intensively investigated in cervical cancer patients. In this study we analyzed and quantified by real-time PCR (RT-PCR) the RNA expression levels of E6, E7, and L1 genes in flash-frozen HPV-16 cervical carcinomas. In addition, the kinetics of expression of E6, E7, and L1 in HPV-16-infected primary cell lines established as long-term cultures in vitro was also evaluated at RNA and protein levels. Finally, in order to evaluate the therapeutic potential of L1-specific CD4+ and CD8+ T lymphocytes responses in cervical cancer patients, L1 VLP-loaded dendritic cells (DCs) were used to stimulate peripheral blood lymphocytes from cervical cancer patients and such responses were compared to those elicited by the E7 oncoprotein. We show that 22 of 22 (100%) flash-frozen cervical biopsy samples collected from HPV-16-positive cervical cancer patients harbor L1, in addition to E6 and E7 RNA, as detected by RT-PCR. E7 RNA copy number (mean, 176.2) was significantly higher in HPV-16-positive cervical cancers compared to the E6 RNA copy number (mean, 47.3) and the L1 copy number (mean, 58.3) (P < 0.0001 and P < 0.001, respectively). However, no significant differences in expression levels between E6 and L1 were found. Kinetic studies of E6, E7, and L1 RNA and protein expression levels in primary tumors showed a sharp reduction in L1 expression after multiple in vitro passages compared to E6 and E7. Autologous DCs pulsed with HPV-16 VLPs or recombinant full-length E7 elicited strong type 1 L1- and E7-specific responses in CD4+ and CD8+ T cells from cervical cancer patients. Importantly, L1 VLP-specific CD8+ T lymphocytes expressed strong cytolytic activity against autologous tumor cells and were as effective as E7-specific cytotoxic T lymphocytes in lysing naturally HPV-16-infected autologous tumor cells. Taken together, these data demonstrate a consistent expression of L1 in primary cervical tumors and the possibility of inducing effective L1/tumor-specific CD4+ and CD8+ T-lymphocyte responses in patients harboring HPV-infected cervical cancer. These results may have important implications for the treatment of patients harboring established HPV-infected lesions with L1 VLPs or combined E7/L1 DC-based vaccinations.Human papillomavirus (HPV) infection represents the most important risk factor for the development of cervical cancer. Although more than 100 distinct HPV genotypes have been described, and at least 20 are associated with cervical cancer, HPV type 16 (HPV-16) is by far the most frequently detected in cervical neoplasia regardless of the geographical origin of the patients (4). In the last few years significant advances have been made in the development of candidate prophylactic vaccine against cervical cancer and HPV-related infections. In several large prospective randomized studies, virus-like particles consisting of the HPV-16 and HPV-18 major capsid protein L1 (L1-VLPs) have shown promise in protecting young healthy females against persistent infection with HPV-16 and HPV-18 and their associated cervical intraepithelial neoplasia (reviewed in reference 12). These data strongly suggest that the implementation of large-scale L1-VLP-based prophylactic vaccinations have the potential to dramatically reduce worldwide cervical cancer rates in the years to come.Unfortunately, because HPV infection is endemic in humans and there is a long latency from HPV infection to the development of invasive cervical cancer in women, even if prophylactic L1-based vaccinations are implemented on a worldwide scale today it would take decades to perceive any significant benefit. Consistent with this view, an estimated 5 million cervical cancer deaths will occur in the next 20 years due to existing HPV infections (4, 12). Thus, the current development of therapeutic vaccines for protection against persistent HPV infections, cervical cancer, and its precursor lesions remains an area of great interest.Although the interactions between the host immune system and HPV-infected cells are still not completely understood, several lines of evidence suggest that protection against HPV-related infections by L1-VLP-based vaccines is likely conferred by the generation of high levels of neutralizing antibodies (12, 38). Nevertheless, a potential crucial role of L1-specific T-cell responses and the involvement of T cells in mediating the production of neutralizing antibodies and antiviral effect in infected hosts has been previously hypothesized (8, 24). This point may be particularly noteworthy in patients harboring HPV-infected cervical lesions because several studies have demonstrated the critical importance of both cytotoxic (CD8+) and helper (CD4+) T cells in achieving clinical responses (1, 5, 16-18, 20, 23). However, limited information is currently available to evaluate whether cell-mediated immune responses to L1-VLP may have any significant therapeutic effect in cervical cancer patients harboring HPV-16 positive tumors. Furthermore, to our knowledge, no direct comparison of the therapeutic efficacy of L1 and E7-specific immune responses against naturally HPV-16-infected cervical cancer have been yet reported in human patients.In the present study we have analyzed and quantified by highly sensitive real-time PCR (RT-PCR) the RNA levels of E6, E7, and L1 in flash-frozen biopsy specimens obtained from HPV-16-infected cervical carcinomas and in short- and long-term primary cultures of HPV-16-positive cervical tumors. In addition, we have studied the kinetics of expression of these genes and proteins during the establishment of HPV-16-positive primary tumors in vitro. Finally, using completely autologous systems of naturally infected HPV-16-positive human tumors, we have carefully studied the phenotype and function of L1-specific CD4+ and CD8+ T-lymphocyte responses generated by VLP-loaded dendritic cells (DCs) and compared their therapeutic potential to those elicited by DC loaded with the E7 oncoprotein.  相似文献   
3.
The aging process is often paralleled by decreases in muscle and increases in fat mass. At the extreme these two processes lead to a condition known as "sarcopenic obesity" (Roubenoff R. Ann NY Acad Sci 904: 553-557, 2000). Research suggests that inflammatory cytokines produced by adipose tissue, especially visceral fat, accelerate muscle catabolism and thus contribute to the vicious cycle that initiates and sustains sarcopenic obesity. We tested the hypothesis that obesity and poor muscle strength, hallmarks of sarcopenic obesity, are associated with high circulating levels of proinflammatory cytokines in a random sample of the residents of two municipalities in the Chianti geographic area (Tuscany, Italy). The study sample consisted of 378 men and 493 women 65 yr and older with complete data on anthropometrics, handgrip strength, and inflammatory markers. Participants were cross-classified according to sex-specific tertiles of waist circumference and grip strength and according to a cut point for obesity of body mass index > or =30 kg/m(2). After adjusting for age, sex, education, smoking history, physical activity, and history of comorbid diseases, components of sarcopenic obesity were associated with elevated levels of IL-6, C-reactive protein, IL-1 receptor antagonist, and soluble IL-6 receptor (P < 0.05). Our findings suggest that global obesity and, to a greater extent, central obesity directly affect inflammation, which in turn negatively affects muscle strength, contributing to the development and progression of sarcopenic obesity. These results suggest that proinflammatory cytokines may be critical in both the development and progression of sarcopenic obesity.  相似文献   
4.
Several indole derivatives, that were highly potent ligands of GluN2B-subunit-containing N-methyl-d-aspartate (NMDA) receptor, also demonstrated antioxidant properties in ABTS method. In particular, the 2-(4-benzylpiperidin-1-yl)-1-(5-hydroxy-1H-indol-3-yl)ethanone (1) proved to be a dual-effective neuroprotective agent. With the aim to increase the antioxidant properties we added a catechol moiety onto piperidine moiety. The designed hybrid derivative 3,4-dihydroxy-N-[1-[2-(5-hydroxy-1H-indol-3-yl)-2-oxoethyl]piperidin-4-yl]benzamide (10) was the most effective antioxidant agent (>94.1 ± 0.1% of inhibition at 17 μM) and showed GluN2B/NMDA receptor affinity at low micromolar concentration (IC50 0.66 μM). By means of computational studies we explored the effect of the presence of this antioxidant fragment during the recognition process to binding pocket.  相似文献   
5.
The centromere is an essential structure in the chromosomes of all eukariotes and is central to the mechanism that ensures proper segregation during mitosis and meiosis. The comparison of DNA sequence motifs, organization and kinetocore components from yeast to man is beginning to indicate that, although centromeres are highly variable DNA elements, a conserved pattern of sequence arrangement and function is emerging. We have identified and characterized the first satellite DNA (P.k.SAT) from microbat species Pipistrellus kuhli. The presence of mammalian CENP-B box and yeast CDEIII box could indicate the participation of P.k.SAT in centromere organization.  相似文献   
6.
Diatoms are major contributors to global carbon fixation and constitute a significant portion of biofilms found in lotic ecosystems. Despite their widespread abundance and the fact that extensive studies have been performed on morphological features of frustules, molecular tools for the identification of diatoms are not commonly available. This study focuses on the development of oligonucleotide probes for the detection of diatom species relevant to water quality assessment. The selected panel of diatoms covers all the species found in water of varying quality from the rivers of central-East Apennine (Italy). Small subunit rRNA-targeted probes were applied to a microarray platform as well as to a new technique termed Primer–Probe, with the aim of obtaining a molecular tool suitable for accurate identification of both single and mixed species diatom populations. The Primer–Probe technique together with dot-blot assays proved to be ideal for the preliminary screening of a large set of DNA oligonucleotides designed by ARB software. It was shown that microarrays, as a promising technology for rapid and simultaneous detection of a wide range of species-specific genetic markers, can be adapted to monitor changes within a diatom community. It is suggested that microarrays will provide a molecular basis for microbial identification to support standard microscopy techniques used by ecologists and environmental scientists for monitoring water quality.  相似文献   
7.
8.
9.
8-[2-(4-Aryl-1-piperazinyl)ethyl]-2H-1,4-benzoxazin-3(4H)-ones have been identified as highly potent 5-HT1A/B/D receptor antagonists with and without additional SerT activity and a high degree of selectivity over hERG potassium channels. Modulation of the different target activities gave compounds with a range of profiles suitable for further in vivo characterization.  相似文献   
10.
Communication, an essential prerequisite for sociality, involves the transmission of signals. A signal can be defined as any action or trait produced by one animal, the sender, that produces a change in the behaviour of another animal, the receiver. Secondary sexual signals are often used for mate choice because they may inform on a potential partner's quality. Verreaux's sifaka (Propithecus verreauxi) is characterized by the presence of two different morphs of males (bimorphism), which can show either a stained or clean chest. The chest becomes stained by secretions of the sternal gland during throat marking (rubbing throat and chest on a vertical substrate while smearing the scent deposition). The role of the chest staining in guiding female mate choice was previously hypothesized but never demonstrated probably due to the difficulty of observing sifaka copulations in the wild. Here we report that stained-chested males had a higher throat marking activity than clean-chested males during the mating season, but not during the birth season. We found that females copulated more frequently with stained-chested males than the clean-chested males. Finally, in agreement with the biological market theory, we found that clean-chested males, with a lower scent-releasing potential, offered more grooming to females. This "grooming for sex" tactic was not completely unsuccessful; in fact, half of the clean-chested males copulated with females, even though at low frequency. In conclusion, the chest stain, possibly correlated with different cues targeted by females, could be one of the parameters which help females in selecting mates.  相似文献   
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