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D. F. Coelho E. Silveira A. Pessoa Junior E. B. Tambourgi 《Bioprocess and biosystems engineering》2013,36(2):185-192
This paper focuses on the feasibility of unconventional aqueous two-phase systems for bromelain purification from pineapple processing waste. The main difference in comparison with conventional systems is the integration of the liquid–liquid extraction technique with fractional precipitation, which can decrease the protein content with no loss of biological activity by removing of unwanted molecules. The analysis of the results was based on the response surface methodology and revealed that the use of the desirability optimisation methodology (DOM) was necessary to achieve higher purification factor values and greater bromelain recovery. The use of DOM yielded an 11.80-fold purification factor and 66.38 % biological activity recovery using poly(ethylene glycol) (PEG) with a molar mass of 4,000, 10.86 % PEG concentration (m/m) and 36.21 % saturation of ammonium sulphate. 相似文献
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Ana Cravo Sá Ana Fermento Dalila Neves Sara Ferreira Teresa Silva Carina Marques Coelho Aude Vaandering Ana Roma Sérgio Quaresma Emmanuel Bonnarens 《Reports of Practical Oncology and Radiotherapy》2018,23(1):61-67
Aim
In this study, we intend to compare two different setup procedures for female breast cancer patients.Background
Imaging in radiotherapy provides a precise localization of the tumour, increasing the accuracy of the treatment delivery in breast cancer.Materials and methods
Twenty breast cancer patients who underwent whole breast radiotherapy (WBRT) were selected for this study. Patients were divided into two groups of ten. Group one (G1) was positioned by tattoos and then the patient positioning was adjusted with the aid of AlignRT (Vision RT, London, UK). In group two (G2), patients were positioned only by tattoos. For both groups, the first 15 fractions were analyzed, a daily kilovoltage (kV) cone beam computed tomography (CBCT) image was made and then the rotational and translational displacements and, posteriorly, the systematic (Σ) and random (σ) errors were analyzed.Results
The comparison of CBCT displacements for the two groups showed a statistically significant difference in the translational left–right (LR) direction (ρ = 0.03), considering that the procedure with AlignRT system has smaller lateral displacements. The results of systematic (Σ) and random (σ) errors showed that for translational displacements the group positioned only by tattoos (G2) demonstrated higher values of errors when compared with the group positioned with the aid of AlignRT (G1).Conclusions
AlignRT could help the positioning of breast cancer patients; however, it should be used with another imaging method. 相似文献156.
Molecular evidence and clinical importance of β‐arrestins expression in patients with acromegaly 下载免费PDF全文
Maria Caroline Alves Coelho Marina Lipkin Vasquez Luiz Eduardo Wildemberg Mari C. Vázquez‐Borrego Luciana Bitana Aline Helen da Silva Camacho Débora Silva Liana Lumi Ogino Nina Ventura Leila Chimelli Raul M. Luque Leandro Kasuki Mônica R. Gadelha 《Journal of cellular and molecular medicine》2018,22(4):2110-2116
β‐arrestins seem to have a role in endocytosis and desensitization of somatostatin receptor subtype 2 (sst2) and could be associated with the responsiveness to somatostatin receptor ligands (SRL) in patients with acromegaly. To investigate the in vivo correlation between β‐arrestins 1 and 2 with sst2, sst5 and dopamine receptor subtype 2 (D2) expressions, and the association of β‐arrestins with response to first‐generation SRL and invasiveness in somatotropinomas. β‐arrestins 1 and 2, sst2, sst5 and D2 mRNA expressions were evaluated by quantitative real‐time RT‐PCR on tumoral tissue of 96 patients. Moreover, sst2 and sst5 protein expressions were also evaluated in 40 somatotropinomas by immunohistochemistry. Response to SRL, defined as GH <1 μg/l and normal IGF‐I levels, was assessed in 40 patients. The Knosp‐Steiner criteria were used to define invasiveness. Median β‐arrestin 1, β‐arrestin 2, sst2, sst5 and D2 mRNA copy numbers were 478; 9375; 731; 156 ; and 3989, respectively. There was a positive correlation between β‐arrestins 1 and 2 (R = 0.444, P < 0.001). However, no correlation between β‐arrestins and sst2, sst5 (mRNA and protein levels) or D2 was found. No association was found between β‐arrestins expression and SRL responsiveness or tumour invasiveness. Although previous data suggest a putative correlation between β‐arrestins and sst2, our data clearly indicated that no association existed between β‐arrestins and sst2, sst5 or D2 expression, nor with response to SRL or tumour invasiveness. Therefore, further studies are required to clarify whether β‐arrestins have a role in the response to treatment with SRL in acromegaly. 相似文献
157.
Robson Campos Silva Daniella Maria Coelho Britto Wagner de Fátima Pereira Gustavo Eustáquio Alvin Brito-Melo Cristiane Tolentino Machado Marcelo Mattos Pedreira 《Reproductive biology》2018,18(2):169-176
Doxorubicin (DXR) is a widely used chemotherapeutic anticancer agent that has potent activity against several solid and non-solid human malignant tumors, including childhood malignancies. However, DXR has serious toxic effects on tissues with rapid cell cycles, such as myeloid and lymphatic tissues, intestinal mucosa, testes and ovaries. In the present study, the short- and medium-term toxic effects of DXR on the reproductive system of male Wistar rats were evaluated using morphometric and stereological tools to quantify damage to the seminiferous epithelium. Adult male Wistar rats were treated with dose of 7.5?mg/kg of DXR and were sacrificed at seven, 14, 21 and 28?days after treatment. The testes were fixed in glutaraldehyde solution, routinely processed and embedded in plastic for evaluation under a light microscope. A significant reduction in testis weight was found as a result of massive germ cell apoptosis. Differences in comparison to the control group were found in the relative frequency of all stages of the seminiferous epithelium cycle, with significant differences for stages VIII–XI. Apoptosis significantly decreased the number of pachytene spermatocytes in the stages evaluated (I, II–III and VIII) at seven and 14?days. At 21 and 28?days after treatment, the testes exhibited the massive loss of germ cells that resulted in a missing cell layer. Moreover, reductions in the height of seminiferous tubules, tubular diameter and tubular compartment as well as an increase in the intertubular compartment were found in the period studied. 相似文献
158.
Carolina R. D. Boaventura-Novaes Evandro Novaes Elias E. S. Mota Mariana P. C. Telles Alexandre S. G. Coelho Lázaro J. Chaves 《Tree Genetics & Genomes》2018,14(5):76
Knowing how microevolutionary processes, such as genetic drift and natural selection, shape variation in adaptive traits is strategic for conservation measures. One way to estimate local adaptation is to compare divergences in quantitative traits (QST) and neutral loci (FST). Therefore, we have assessed the pattern of phenotypic and molecular genetic divergence among natural subpopulations of the fruit tree Eugenia dysenterica DC. A provenance and progeny test was performed to assess the quantitative traits of the subpopulations collected in a wide distribution area of the species in the Brazilian Cerrado. The sampled environments are in a biodiversity hotspot with heterogeneous soil and climate conditions. By associating quantitative trait variation in initial seedling development with neutral microsatellite marker variation, we tested the local adaptation of the traits by the QST–FST contrast. Genetic drift was prevalent in the phenotypic differentiation among the subpopulations, although the traits seedling emergence time and root green mass, which are relevant for adaptation to the Cerrado climate, showed signs of uniform selection. Our results suggest that E. dysenterica has a spatial genetic structure divided into two large groups, separated by a line that divides the Cerrado biome in a southwestern to northeastern direction. This structure must be taken into account for managing E. dysenterica genetic resources both for conservation and breeding purposes. 相似文献
159.
Janay?Stefany?Carneiro?Araujo Bruno?Cruz?de?Souza David?Bacelar?Costa Junior Larissa de Mattos?Oliveira Isis?Bugia?Santana Angelo?Amancio?Duarte Pedro?Sousa?Lacerda Manoelito Coelho?dos?Santos Junior Franco?Henrique?Andrade?LeiteEmail author 《Journal of molecular modeling》2018,24(8):220
Malaria is the world’s most widespread protozoan infection, being responsible for more than 445,000 annual deaths. Among the malaria parasites, Plasmodium falciparum is the most prevalent and lethal. In this context, the search for new antimalarial drugs is urgently needed. P. falciparum superoxide dismutase (PfSOD) is an important enzyme involved in the defense mechanism against oxidative stress. The goal of this study was to identify through hierarchical screening on pharmacophore models and molecular dynamics (MD), promising allosteric PfSOD inhibitors that do not show structural requirements for human inhibition. MD simulations of 1000 ps were performed on PfSOD using GROMACS 5.1.2. For this, the AMBER99SB-ILDN force field was adapted to describe the metal-containing system. The simulations indicated stability in the developed system. Therefore, a covariance matrix was generated, in which it was possible to identify residues with correlated and anticorrelated movements with the active site. These results were associated with the results found in the predictor of allosteric sites, AlloSitePro, which affirmed the ability of these residues to delimit an allosteric site. Then, after successive filtering of the Sigma-Aldrich® compounds database for HsSOD1 and PfSOD pharmacophores, 152 compounds were selected, also obeying Lipinski’s rule of 5. Further filtering of those compounds based on molecular docking results, toxicity essays, availability, and price filtering led to the selection of a best compound, which was then submitted to MD simulations of 20,000 ps on the allosteric site. The study concludes that the ZINC00626080 compound could be assayed against SODs. 相似文献
160.
Larissa?de Mattos?Oliveira Janay?Stefany?Carneiro?Araújo David?Bacelar?Costa Junior Isis?Bugia?Santana Angelo?Amancio?Duarte Franco?Henrique?Andrade?Leite Raquel?Guimar?es?Benevides Manoelito?Coelho dos?Santos JuniorEmail authorView authors OrcID profile 《Journal of molecular modeling》2018,24(11):314
Leishmaniasis is caused by protozoa of the genus Leishmania spp. and is considered the second most important protozoa in the world due to the number of cases and mortality. Despite its importance in terms of public health, the treatment of patients is limited and has mostly low levels of efficacy and safety. Farnesyl pyrophosphate synthase (FPPS) acts in the early stages of isoprenoid synthesis, and is important for maintaining the integrity of the lipid bilayer of the parasite that causes the disease. The aim of this work was to identify one potential inhibitor of the FPPS of Leishmania major through virtual screening by pharmacophore modeling and docking. A total of 85,000 compounds from a natural products database (ZINC15) was submitted for virtual hierarchical screening, and the top ranked molecule in both methods was analyzed by intermolecular interaction profile and 20 ns molecular dynamics simulations. These results showed a promising compound from natural products that mimic the major interactions present in the substrate/inhibitor. 相似文献