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141.
da Silva Breno Augusto Tabosa Thome Pascoalino Liege Aguiar de Souza Ricardo Luiz Muniz Edvani Curti Curti Priscila Schroeder 《Polymer Bulletin》2020,77(3):1157-1176
Polymer Bulletin - In this work, electrospun fibers of poly(butylene adipate-co-terephthalate) (PBAT) and poly(N-isopropylacrylamide) (PNIPAAm) blends, PBAT/PNIPAAm, with different mass ratios,... 相似文献
142.
de Oliveira Amanda Gerhardt Moreno Janaina Fernandes de Sousa Ana Maria Furtado Esccio Viviane Alves de Oliveira Cavalcanti Guimares Maria Jos da Silva Ana Lucia Nazareth 《Polymer Bulletin》2020,77(6):2889-2904
Polymer Bulletin - Investigating the compatibility mechanism of hybrid composites based on two polymers and one mineral nanofiller is a challenge that needs to be better understood. This study... 相似文献
143.
Anna Kloska Grzegorz M. Cech Dariusz Nowicki Monika Macig-Dorszyska Aleksandra E. Bogucka Stephanie Markert Drte Becher Katarzyna Potrykus Paulina Czaplewska Agnieszka Szalewska-Paasz 《International journal of molecular sciences》2022,23(2)
Osmotic changes are common challenges for marine microorganisms. Bacteria have developed numerous ways of dealing with this stress, including reprogramming of global cellular processes. However, specific molecular adaptation mechanisms to osmotic stress have mainly been investigated in terrestrial model bacteria. In this work, we aimed to elucidate the basis of adjustment to prolonged salinity challenges at the proteome level in marine bacteria. The objects of our studies were three representatives of bacteria inhabiting various marine environments, Shewanella baltica, Vibrio harveyi and Aliivibrio fischeri. The proteomic studies were performed with bacteria cultivated in increased and decreased salinity, followed by proteolytic digestion of samples which were then subjected to liquid chromatography with tandem mass spectrometry analysis. We show that bacteria adjust at all levels of their biological processes, from DNA topology through gene expression regulation and proteasome assembly, to transport and cellular metabolism. The finding that many similar adaptation strategies were observed for both low- and high-salinity conditions is particularly striking. The results show that adaptation to salinity challenge involves the accumulation of DNA-binding proteins and increased polyamine uptake. We hypothesize that their function is to coat and protect the nucleoid to counteract adverse changes in DNA topology due to ionic shifts. 相似文献
144.
Flvia Melo Cunha de Pinho Pessoa Caio Bezerra Machado Emerson Lucena da Silva Laudreísa da Costa Pantoja Rodrigo Monteiro Ribeiro Maria Elisabete Amaral de Moraes Manoel Odorico de Moraes Filho Raquel Carvalho Montenegro Andr Salim Khayat Caroline Aquino Moreira-Nunes 《International journal of molecular sciences》2022,23(7)
The increasing numbers of cancer cases worldwide and the exceedingly high mortality rates of some tumor subtypes raise the question about if the current protocols for cancer management are effective and what has been done to improve upon oncologic patients’ prognoses. The traditional chemo-immunotherapy options for cancer treatment focus on the use of cytotoxic agents that are able to overcome neoplastic clones’ survival mechanisms and induce apoptosis, as well as on the ability to capacitate the host’s immune system to hinder the continuous growth of malignant cells. The need to avert the highly toxic profiles of conventional chemo-immunotherapy and to overcome the emerging cases of tumor multidrug resistance has fueled a growing interest in the field of precision medicine and targeted molecular therapies in the last couple of decades, although relatively new alternatives in oncologic practices, the increased specificity, and the positive clinical outcomes achieved through targeted molecular therapies have already consolidated them as promising prospects for the future of cancer management. In recent years, the development and application of targeted drugs as tyrosine kinase inhibitors have enabled cancer treatment to enter the era of specificity. In addition, the combined use of targeted therapy, immunotherapy, and traditional chemotherapy has innovated the standard treatment for many malignancies, bringing new light to patients with recurrent tumors. This article comprises a series of clinical trials that, in the past 5 years, utilized kinase inhibitors (KIs) as a monotherapy or in combination with other cytotoxic agents to treat patients afflicted with solid tumors. The results, with varying degrees of efficacy, are reported. 相似文献
145.
146.
Diane Cleydes Baía da Silva Leonardo Oliveira Bittencourt Daiane Claydes Baia-da-Silva Victoria Santos Chemelo Luciana Eir-Quirino Priscila Cunha Nascimento Mrcia Cristina Freitas Silva Marco Aurelio M. Freire Walace Gomes-Leal Maria Elena Crespo-Lopez Rafael Rodrigues Lima 《International journal of molecular sciences》2022,23(7)
Methylmercury (MeHg) is one of the most dangerous toxic pollutants spread throughout the earth. Chronic MeHg intoxication by contaminated food ingestion is the most common threat to human health, including impairment to the developing fetus. The present study aims at investigating the effects of maternal exposure to MeHg during gestation and lactation on the spinal cord of offspring. Pregnant rats received oral doses of MeHg (40 μg/kg/day) over a period of 42 days (21 gestation and 21 lactation). Control animals received the vehicle only. Total mercury concentration was measured in blood samples from offspring collected at the 41st postnatal day. Counting of motor neurons and immunoreactivity for myelin basic protein (MBP) were assessed in the spinal cords in both control and MeHg-intoxicated animals. Our results showed that MeHg promoted an increase in blood Hg levels. In addition, it caused a reduction in the number of spinal cord motor neurons as well as decreased MBP immunoreactivity in the cervical, thoracic and lumbar segments. Our present findings suggest that MeHg intoxication during rat pregnancy and lactation is associated with a pattern of motor neuron degeneration and downregulation of myelin basic protein in different segments of a developing spinal cord. Further studies are needed to establish the effect of MeHg intoxication in both young and adult rats. 相似文献
147.
Eric Lecorvaisier Sbastien Darche Zaqueu Ernesto da Silva Cristiane Kelly F. da Silva 《Journal of food engineering》2010,96(3):365-373
Biological products contain high moisture content in the harvest period. Such moisture could cause their deterioration in storage. Drying is an interesting solution to keep the quality of these products. Generally, drying process is based on contact of a dry air phase with a wet solid. A theoretical model was developed to describe the dynamic behavior of a forced convection drying process. This model takes into account the entire dynamic phenomenon including turbulence, diffusivity and tortuosity effects. Only the mass transfer of water molecules during vaporization was referred to as an empirical expression. The model thus strongly build, was compared to Thompson’s empirical model. Corn grain was used in the validating process. Transient temperature and water content results are presented. 相似文献
148.
Gustavo Larsen Edgar Lotero Rubn D. Parra Lucía M. Petkovic Hugo S. Silva Srinivasanallur Raghavan 《Applied Catalysis A: General》1995,130(2):213-226
Palladium supported on sulfated zirconia (PdSZ) has been characterized by the n-butane isomerization reaction in the presence of hydrogen, X-ray absorption spectroscopy (XAS) and diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) of adsorbed carbon monoxide. Catalyst calcination at 873 K followed by hydrogen reduction at 513 K results in the formation of 30–40 Å Pd metal clusters, but the surface can only weakly adsorb CO, though stronger than Pd-free, sulfated zirconia catalysts. In the presence of hydrogen, PdSZ has a lower n-butane isomerization activity than SZ, and the Pd function cannot stabilize the reaction at low H2/n-butane ratios. 相似文献
149.
Aditi Mehta Stephanie Dobersch Reinhard H. Dammann Saverio Bellusci Olga N. Ilinskaya Thomas Braun Guillermo Barreto 《International journal of molecular sciences》2015,16(3):4492-4511
The expression ratio between the analysed gene and an internal control gene is the most widely used normalization method for quantitative RT-PCR (qRT-PCR) expression analysis. The ideal reference gene for a specific experiment is the one whose expression is not affected by the different experimental conditions tested. In this study, we validate the applicability of five commonly used reference genes during different stages of mouse lung development. The stability of expression of five different reference genes (Tuba1a, Actb Gapdh, Rn18S and Hist4h4) was calculated within five experimental groups using the statistical algorithm of geNorm software. Overall, Tuba1a showed the least variability in expression among the different stages of lung development, while Hist4h4 and Rn18S showed the maximum variability in their expression. Expression analysis of two lung specific markers, surfactant protein C (SftpC) and Clara cell-specific 10 kDA protein (Scgb1a1), normalized to each of the five reference genes tested here, confirmed our results and showed that incorrect reference gene choice can lead to artefacts. Moreover, a combination of two internal controls for normalization of expression analysis during lung development will increase the accuracy and reliability of results. 相似文献
150.
Andr Neto Carlos Silva Jorge Sousa Horcio Fernandes Carlos Hidalgo Jose Luis De Pablos Sophie Salasca Jean-Marcel Travre Jonathan B. Lister 《Fusion Engineering and Design》2009,84(7-11):1412-1415
The amount of data generated by the infra-red and visible cameras at ITER is expected to be considerably larger than most diagnostics. ITER will have 12 infra-red cameras plus 12 visible cameras in four different equatorial port plugs. Each of the ports will have a Plant System Host (PSH) that will provide a standard image of the plant system to the ITER's Control and Data Access and Communication (CODAC) system.The two key functions of these cameras will be the scientific exploitation with the detection of interesting physics events and the operational protection of the machine, namely the first wall. Already assuming high bandwidth requirements for both audio and video, ITER will provide a separate network for this kind of communication, which will be used to transmit both the experimental and informational data provided by the cameras.This paper presents the current camera plant system design and its interaction with ITER CODAC system and networks. Starting from the camera specifications several alternatives for data collection and compression are discussed. The required inputs from CODAC and a first specification for the internal finite state machine are also presented. Finally, a possible hardware straw man design solution for the plant system hardware is proposed. 相似文献