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1.
Stefania Bellone Karim El-Sahwi Emiliano Cocco Francesca Casagrande Marilisa Cargnelutti Michela Palmieri Eliana Bignotti Chiara Romani Dan-Arin Silasi Masoud Azodi Peter E. Schwartz Thomas J. Rutherford Sergio Pecorelli Alessandro D. Santin 《Journal of virology》2009,83(13):6779-6789
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
2.
3.
Sergio L. Gianizella Thiago F. Martins Valeria C. Onofrio Nair O. Aguiar Waleska Gravena Carlos A. R. do Nascimento Laérzio C. Neto Diogo L. Faria Natália A. S. Lima Monica R. Solorio Louise Maranhão Ivan J. Lima Iury V. D. Cobra Tamily Santos Gerson P. Lopes Emiliano E. Ramalho Hermes R. Luz Marcelo B. Labruna 《Experimental & applied acarology》2018,74(2):177-183
The tick fauna of Brazil is currently composed by 72 species. The state of Amazonas is the largest of Brazil, with an area of ≈ 19% of the Brazilian land. Besides its vast geographic area, only 19 tick species have been reported for Amazonas. Herein, lots containing ticks from the state of Amazonas were examined in three major tick collections from Brazil. A total of 5933 tick specimens were examined and recorded, comprising 2693 males, 1247 females, 1509 nymphs, and 484 larvae. These ticks were identified into the following 22 species: Amblyomma cajennense sensu lato, Amblyomma calcaratum, Amblyomma coelebs, Amblyomma dissimile, Amblyomma dubitatum, Amblyomma geayi, Amblyomma goeldii, Amblyomma humerale, Amblyomma latepunctatun, Amblyomma longirostre, Amblyomma naponense, Amblyomma oblongoguttatum, Amblyomma ovale, Amblyomma rotundatum, Amblyomma scalpturatum, Amblyomma varium, Dermacentor nitens, Haemaphysalis juxtakochi, Ixodes cf. Ixodes fuscipes, Ixodes luciae, Rhipicephalus microplus, Rhipicephalus sanguineus sensu lato. Ticks were collected from 17 (27.4%) out of the 62 municipalities that currently compose the state of Amazonas. The following four species are reported for the first time in the state of Amazonas: A. coelebs, A. dubitatum, H. juxtakochi, and Ixodes cf. I. fuscipes. The only tick species previously reported for Amazonas and not found in the present study is Amblyomma parvum. This study provides a great expansion of geographical and host records of ticks for the state of Amazonas, which is now considered to have a tick fauna composed by 23 species. It is noteworthy that we report 1391 Amblyomma nymphs that were identified to 13 different species. 相似文献
4.
Anna Bocci Sandro Lovari Muhammad Zafar Khan Emiliano Mori 《European Journal of Wildlife Research》2017,63(6):92
The snow leopard Panthera uncia coexists with the wolf Canis lupus throughout most of its distribution range. We analysed the food habits of snow leopards and wolves in their sympatric range in the Karakoram mountains of Pakistan. A total of 131 genotyped scats (N?=?74, snow leopard; N?=?57, Tibetan wolf) were collected during the cold periods (i.e. winter and spring) of 2011 and 2012 in the Hushey valley. Large mammals, i.e. livestock and ibex, accounted for 84.8 and 83.1% of the diet (relative frequency) of the snow leopard and the wolf, respectively. Domestic prey was the staple of the diet of both snow leopards (66.6%) and wolves (75.1%). Ibex Capra ibex, the only wild ungulate in our study area, contributed 18.2 and 16.9% of relative frequencies in the diets of the snow leopard and the wolf, respectively. In winter, the snow leopard heavily relied on domestic sheep (43.3%) for food, whereas the wolf preyed mainly on domestic goats (43.4%). Differently from other study areas, both snow leopards and wolves showed no apparent prey preference (Jacobs index: snow leopard min. ??0.098, max. 0.102; Tibetan wolf min. ??0.120, max. 0.03). In human depauperate areas, with livestock and only a few wild prey, should competitive interactions arise, two main scenarios could be expected, with either predator as a winner. In both cases, the best solution could primarily impinge on habitat restoration, so that a balance could be found between these predators, who have already coexisted for thousands of years. 相似文献
5.
Emiliano E Romero-Ale Ana I Olives M Antonia Martín Benito del Castillo Pilar López-Alvarado J Carlos Menéndez 《Luminescence》2005,20(3):162-169
The carbazole ring is the basic structure present in the fluorescence derivatization reagents 9-chlorocarbonylcarbazole and 9-carbazolylacetic acid. The fluorescence behaviour of these carbazole derivatives was studied in solvents with different polarities (cyclohexane, ethanol, acetonitrile, water) and at different pH values (4.5 and 8.8). The influence of the low polarity environment afforded by 2-hydroxypropyl-beta-cyclodextrin (HPbeta-CD) is also described. The behaviour of the fluorescent reagents is compared to the model molecules carbazole and 9-methylcarbazole. For all derivatives studied, a bathochromic shift in the fluorescence emission maxima was observed when the solvent polarity was increased. A bathochromic shift was observed in dioxane solutions, which can be ascribed to the peculiar behaviour of this solvent. The changes in the fluorescence intensity in the case of 9-carbazolylacetic acid can be related to the ionization of the carboxylic acid group. Inclusion into the cavity of HPbeta-CD allows emission spectra to be obtained close to those obtained in ethanolic solutions with a remarkable enhancement in the fluorescence intensity, depending on the chemical structure of the carbazole derivative included. 相似文献
6.
Tomàs Pinós Mario Marotta Eduard Gallardo Isabel Illa Jorge Díaz-Manera Emiliano Gonzalez-Vioque Elena García-Arumí Antoni L. Andreu Ramon Martí 《Mitochondrion》2011,11(1):228-233
We report a heteroplasmic novel mutation m.5636T>C in the mt-tRNAAla in a patient with bilateral ptosis and ophthalmoparesis in whom a muscle biopsy showed cytochrome c oxdidase (COX) negative and ragged red fibers. Using laser capture microdissection we have isolated COX negative fibers and COX positive fibers from the muscle of the patient and determined that the mutation load was clearly increased in COX negative muscle fibers. Additionally, the mutated m.5636T nucleotide is conserved in all the mammal and non-mammal species analyzed and might be structurally relevant as it is located in a position involved in the formation of tertiary structure of canonical mitochondrial tRNAs. 相似文献
7.
Bingxin Wang Daniel G. Rocha Mark I. Abrahams Andr P. Antunes Hugo C. M. Costa Andr Luis Sousa Gonalves Wilson Roberto Spironello Milton Jos de Paula Carlos A. Peres Juarez Pezzuti Emiliano Ramalho Marcelo Lima Reis Elildo Carvalho Jr Fabio Rohe David W. Macdonald Cedric Kai Wei Tan 《Ecology and evolution》2019,9(9):5049-5062
Amazonia forest plays a major role in providing ecosystem services for human and sanctuaries for wildlife. However, ongoing deforestation and habitat fragmentation in the Brazilian Amazon has threatened both. The ocelot is an ecologically important mesopredator and a potential conservation ambassador species, yet there are no previous studies on its habitat preference and spatial patterns in this biome. From 2010 to 2017, twelve sites were surveyed, totaling 899 camera trap stations, the largest known dataset for this species. Using occupancy modeling incorporating spatial autocorrelation, we assessed habitat use for ocelot populations across the Brazilian Amazon. Our results revealed a positive sigmoidal correlation between remote‐sensing derived metrics of forest cover, disjunct core area density, elevation, distance to roads, distance to settlements and habitat use, and that habitat use by ocelots was negatively associated with slope and distance to river/lake. These findings shed light on the regional scale habitat use of ocelots and indicate important species–habitat relationships, thus providing valuable information for conservation management and land‐use planning. 相似文献
8.
Lasse T. Keetz Eva Lieungh Kaveh Karimi-Asli Sonya R. Geange Emiliano Gelati Hui Tang Yeliz A. Yilmaz Kjetil S. Aas Inge H. J. Althuizen Anders Bryn Stefanie Falk Rosie Fisher Anne Fouilloux Peter Horvath Sunniva Indrehus Hanna Lee Danica Lombardozzi Frans-Jan W. Parmentier Norbert Pirk Vigdis Vandvik Ane V. Vollsnes Olav Skarpaas Frode Stordal Lena M. Tallaksen 《Global Change Biology》2023,29(15):4440-4452
Dynamic Global Vegetation Models (DGVMs) provide a state-of-the-art process-based approach to study the complex interplay between vegetation and its physical environment. For example, they help to predict how terrestrial plants interact with climate, soils, disturbance and competition for resources. We argue that there is untapped potential for the use of DGVMs in ecological and ecophysiological research. One fundamental barrier to realize this potential is that many researchers with relevant expertize (ecology, plant physiology, soil science, etc.) lack access to the technical resources or awareness of the research potential of DGVMs. Here we present the Land Sites Platform (LSP): new software that facilitates single-site simulations with the Functionally Assembled Terrestrial Ecosystem Simulator, an advanced DGVM coupled with the Community Land Model. The LSP includes a Graphical User Interface and an Application Programming Interface, which improve the user experience and lower the technical thresholds for installing these model architectures and setting up model experiments. The software is distributed via version-controlled containers; researchers and students can run simulations directly on their personal computers or servers, with relatively low hardware requirements, and on different operating systems. Version 1.0 of the LSP supports site-level simulations. We provide input data for 20 established geo-ecological observation sites in Norway and workflows to add generic sites from public global datasets. The LSP makes standard model experiments with default data easily achievable (e.g., for educational or introductory purposes) while retaining flexibility for more advanced scientific uses. We further provide tools to visualize the model input and output, including simple examples to relate predictions to local observations. The LSP improves access to land surface and DGVM modelling as a building block of community cyberinfrastructure that may inspire new avenues for mechanistic ecosystem research across disciplines. 相似文献
9.
A common cortical substrate activated by horizontal and vertical sound movement in the human brain 总被引:7,自引:0,他引:7
Perception of movement in acoustic space depends on comparison of the sound waveforms reaching the two ears (binaural cues) as well as spectrotemporal analysis of the waveform at each ear (monaural cues). The relative importance of these two cues is different for perception of vertical or horizontal motion, with spectrotemporal analysis likely to be more important for perceiving vertical shifts. In humans, functional imaging studies have shown that sound movement in the horizontal plane activates brain areas distinct from the primary auditory cortex, in parietal and frontal lobes and in the planum temporale. However, no previous work has examined activations for vertical sound movement. It is therefore difficult to generalize previous imaging studies, based on horizontal movement only, to multidimensional auditory space perception. Using externalized virtual-space sounds in a functional magnetic resonance imaging (fMRI) paradigm to investigate this, we compared vertical and horizontal shifts in sound location. A common bilateral network of brain areas was activated in response to both horizontal and vertical sound movement. This included the planum temporale, superior parietal cortex, and premotor cortex. Sounds perceived laterally in virtual space were associated with contralateral activation of the auditory cortex. These results demonstrate that sound movement in vertical and horizontal dimensions engages a common processing network in the human cerebral cortex and show that multidimensional spatial properties of sounds are processed at this level. 相似文献
10.
Lucia Monti Donatella Donati Elisabetta Menci Samuele Cioni Matteo Bellini Irene Grazzini Sara Leonini Paolo Galluzzi Sauro Severi Luca Burroni Alfredo Casasco Lucia Morbidelli Emiliano Santarnecchi Pietro Piu 《PloS one》2015,10(2)
Literature has suggested that changes in brain flow circulation occur in patients with multiple sclerosis. In this study, digital subtraction angiography (DSA) was used to measure the absolute CCT value in MS patients and to correlate its value to age at disease onset and duration, and to expand disability status scale (EDSS). DSA assessment was performed on eighty MS patients and on a control group of forty-four age-matched patients. CCT in MS and control groups was calculated by analyzing the angiographic images. Lesion and brain volumes were calculated in a representative group of MS patients. Statistical correlations among CCT and disease duration, age at disease onset, lesion load, brain volumes and EDSS were considered. A significant difference between CCT in MS patients (mean = 4.9s; sd = 1.27s) and control group (mean = 2.8s; sd = 0.51s) was demonstrated. No significant statistical correlation was found between CCT and the other parameters in all MS patients. Significantly increased CCT value in MS patients suggests the presence of microvascular dysfunctions, which do not depend on clinical and MRI findings. Hemodynamic changes may not be exclusively the result of a late chronic inflammatory process. 相似文献