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931.
Vinicius C. Santana Mariana O. Diniz Francisco A. M. O. Cariri Armando M. Ventura Edécio Cunha-Neto Rafael R. Almeida Marco A. Campos Graciela K. Lima Luís C. S. Ferreira 《PloS one》2013,8(8)
Millions of people worldwide are currently infected with human papillomavirus (HPV), herpes simplex virus (HSV) or human immunodeficiency virus (HIV). For this enormous contingent of people, the search for preventive and therapeutic immunological approaches represents a hope for the eradication of latent infection and/or virus-associated cancer. To date, attempts to develop vaccines against these viruses have been mainly based on a monovalent concept, in which one or more antigens of a virus are incorporated into a vaccine formulation. In the present report, we designed and tested an immunization strategy based on DNA vaccines that simultaneously encode antigens for HIV, HSV and HPV. With this purpose in mind, we tested two bicistronic DNA vaccines (pIRES I and pIRES II) that encode the HPV-16 oncoprotein E7 and the HIV protein p24 both genetically fused to the HSV-1 gD envelope protein. Mice i.m. immunized with the DNA vaccines mounted antigen-specific CD8+ T cell responses, including in vivo cytotoxic responses, against the three antigens. Under experimental conditions, the vaccines conferred protective immunity against challenges with a vaccinia virus expressing the HIV-derived protein Gag, an HSV-1 virus strain and implantation of tumor cells expressing the HPV-16 oncoproteins. Altogether, our results show that the concept of a trivalent HIV, HSV, and HPV vaccine capable to induce CD8+ T cell-dependent responses is feasible and may aid in the development of preventive and/or therapeutic approaches for the control of diseases associated with these viruses. 相似文献
932.
Philippe de Timary Mariana Cordovil de Sousa Uva Catherine Deno?l Ludger Hebborn Marc Derely Martin Desseilles Olivier Luminet 《PloS one》2013,8(8)
Context
In order to understand how certain personality traits influence the relation between depression symptoms and craving for alcohol, trait self-consciousness (trait SC) was examined during a withdrawal and detoxification program.Methods
Craving (Obsessive and Compulsive Drinking Scale), depressive state (Beck Depression Inventory) and trait SC (Revised Self-Consciousness Scale) were assessed in alcohol-dependent inpatients (DSM-IV, N = 30) both at the beginning (T1: day 1 or 2) and at the end (T2: day 14 to18) of protracted withdrawal during rehabilitation.Results
A significant decrease in craving and depressive symptoms was observed from T1 to T2, while SC scores remained stable. At both times, strong positive correlations were observed between craving and depression. Moreover, regression analyses indicated that trait SC significantly moderated the impact of depression on cravings for alcohol.Limitations
This study was performed on a relatively small sample size. Administration of medications during detoxification treatment can also be a confounding factor. Finally, craving could have been evaluated through other types of measurements.Conclusions
During protracted withdrawal, alcohol craving decreased with the same magnitude as depressive mood. Depressive symptoms were related to alcohol craving but only among patients with high trait SC scores. Our results suggest that metacognitive approaches targeting SC could decrease craving and, in turn, prevent future relapses. 相似文献933.
Eavesdropping involves the acquisition of information from third-party interactions, and can serve to indirectly attribute reputation to individuals. There is evidence on eavesdropping in dogs, indicating that they can develop a preference for people based on their cooperativeness towards others. In this study, we tested dogs’ eavesdropping abilities one step further. In a first experiment, dogs could choose between cooperative demonstrators (the donors) who always gave food to an approaching third person (the beggar); here, the only difference between donors was whether they received positive or negative reactions from the beggar (through verbal and gestural means). Results showed that dogs preferentially approached the donor who had received positive reactions from the beggar. By contrast, two different conditions showed that neither the beggar’s body gestures nor the verbal component of the interaction on their own were sufficient to affect the dogs’ preferences. We also ran two further experiments to test for the possibility of dogs’ choices being driven by local enhancement. When the donors switched places before the choice, dogs chose at random. Similarly, in a nonsocial condition in which donors were replaced by platforms, subjects chose at chance levels. We conclude that dogs’ nonrandom choices in the present protocol relied on the simultaneous presence of multiple cues, such as the place where donors stood and several features of the beggar’s behavior (gestural and verbal reactions, and eating behavior). Nonetheless, we did not find conclusive evidence that dogs discriminated the donors by their physical features, which is a prerequisite of reputation attribution. 相似文献
934.
Vipin Agarwal Mariana Sardo Ingo Scholz Anja Böckmann Matthias Ernst Beat H. Meier 《Journal of biomolecular NMR》2013,56(4):365-377
In this article, we describe third-spin assisted heteronuclear recoupling experiments, which play an increasingly important role in measuring long-range heteronuclear couplings, in particular 15N–13C, in proteins. In the proton-assisted insensitive nuclei cross polarization (PAIN-CP) experiment (de Paëpe et al. in J Chem Phys 134:095101, 2011), heteronuclear polarization transfer is always accompanied by homonuclear transfer of the proton-assisted recoupling (PAR) type. We present a phase-alternating experiment that promotes heteronuclear (e.g. 15N → 13C) polarization transfer while simultaneously minimizing homonuclear (e.g.13C → 13C) transfer (PAIN without PAR). This minimization of homonuclear polarization transfer is based on the principle of the resonant second-order transfer (RESORT) recoupling scheme where the passive proton spins are irradiated by a phase-alternating sequence and the modulation frequency is matched to an integer multiple of the spinning frequency. The similarities and differences between the PAIN-CP and this het-RESORT experiment are discussed here. 相似文献
935.
Mariana Rojas-Aréchiga María C. Mandujano Jordan K. Golubov 《Journal of plant research》2013,126(3):373-386
The response of seed germination towards light and the relationship to seed traits has been studied particularly well in tropical forests. Several authors have shown a clear adaptive response of seed size and photoblastism, however, the evolutionary significance of this relationship for species inhabiting arid environments has not been fully understood and only some studies have considered the response in a phylogenetic context. We collected seeds from 54 cacti species spread throughout the tribe Cacteae to test whether there was correlated evolution of photoblastism, seed traits and germination using a reconstructed phylogeny of the tribe. For each species we determined the photoblastic response under controlled conditions, and seed traits, and analyzed the results using phylogenetically independent contrasts. All studied species were positive photoblastic contrasting with the basal Pereskia suggesting an early evolution of this trait. Seeds from basal species were mostly medium-sized, diverging into two groups. Seeds tend to get smaller and lighter suggesting an evolution to smaller sizes. No evidence exists of a relationship between seed size and photoblastic response suggesting that the photoblastic response within members of this tribe is not adaptive though it is phylogenetically fixed and that is coupled with environmental cues that fine tune the germination response. 相似文献
936.
Mariana Lazarini Fabiola Traina João A. Machado-Neto Karin S.A. Barcellos Yuri B. Moreira Marcelo M. Brandão Sergio Verjovski-Almeida Anne J. Ridley Sara T. Olalla Saad 《生物化学与生物物理学报:疾病的分子基础》2013,1832(2):365-374
Background: Several Rho GTPase-activating proteins (RhoGAPs) are implicated in tumor progression through their effects on Rho GTPase activity. ARHGAP21 is a RhoGAP with increased expression in head and neck squamous cell carcinoma and with a possible role in glioblastoma tumor progression, yet little is known about the function of ARHGAP21 in cancer cells. Here we studied the role of ARHGAP21 in two prostate adenocarcinoma cell lines, LNCaP and PC3, which respectively represent initial and advanced stages of prostate carcinogenesis. Results: ARHGAP21 is located in the nucleus and cytoplasm of both cell lines and its depletion resulted in decreased proliferation and increased migration of PC3 cells but not LNCaP cells. In PC3 cells, ARHGAP21 presented GAP activity for RhoA and RhoC and induced changes in cell morphology. Moreover, its silencing altered the expression of genes involved in cell proliferation and cytoskeleton organization, as well as the endothelin-1 canonical pathway. Conclusions: Our results reveal new functions and signaling pathways regulated by ARHGAP21, and indicate that it could contribute to prostate cancer progression. 相似文献
937.
938.
Inês Cunha-Ferreira Inês Bento Ana Pimenta-Marques Swadhin Chandra Jana Mariana Lince-Faria Paulo Duarte Joana Borrego-Pinto Samuel Gilberto Tiago Amado Daniela Brito Ana Rodrigues-Martins Janusz Debski Nikola Dzhindzhev Mónica Bettencourt-Dias 《Current biology : CB》2013,23(22):2245-2254
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939.
940.
Gloria Viviana Cerrillo-Rojas Mariana Tiscareño-Andrade Ana Erika Ochoa-Alfaro Eugenio Pérez-Molphe Balch Ruth Elena Soria-Guerra José Francisco Morales-Domínguez 《Phyton》2020,89(3):715-726
Halophytes are an excellent choice for the study of genes conferring
salt tolerance to salt-sensitive plants and, they are suitable for reclamation and
remediation of saline soil. We develop an in vitro plant propagation protocol
and studies of genes involved with GB and Pro biosynthesis in Suaeda edulis.
Axillary buds were used as explants and cultured in different treatments on Murashige and Skoog (MS) medium supplemented with different concentrations and
combinations of plant growth regulators. The highest number of multiple shoots
was on MS medium containing 1 mg/L Benzyladenine (BA) and / or 2 g/L activated carbon with 5.5 ± 06 shoots per explant. The identification and expression
analysis of genes involved in glycine betaine (GB) biosynthesis were S-adenosylmethionine synthetase (SAMS), choline monooxygenase (CMO) and betaine aldehyde dehydrogenase (BADH), and for proline (Pro) was pyrroline 5-carboxylate
synthetase (P5CS). These sequences shared 90–95% of identity with others plant
homologous in public databases. The amino acids sequence analysis showed that
all these peptides contain some of the conserved motifs of those kinds of
enzymes. The qRT-PCR analysis revealed a higher expression of SeBADH,
SeCMO, and, SeP5CS genes in the roots and leaves from plants collected in
the field in contrast with from in vitro plants. However, the expression level of
SeSAMS was higher only in the leaves of plants collected in the field when compared to those cultivated in vitro. 相似文献