2,116 research outputs found

    Use of FTIR in the obtention of resins and peptides synthesis in solid phase

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    Despite the increase in peptide chain aggregation, which decreases the rate of coupling reactions, the synthesis and use of very highly substituted resins still remains as a controversial point in the SPPS, due to its clear economical advantages (lesser solvent consumption and higher amount of peptide per synthesis). In order to better investigate the synthesis and the use of very highly substituted resins, the FTIR, NMR and EPR were compared. By FTIR techniques it was possible to follow all the steps of resin synthesis and the factors affecting the aggregation of the chains inside the peptidil-BHAR and MBHAR.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Estadual Paulista Instituto de Química Departamento de Bioquímica e Tecnologia QuímicaUniversidade Federal de São Paulo (UNIFESP) Departamento de BiofísicaUNIFESP, Depto. de BiofísicaSciEL

    Biofilm is a major virulence determinant in bacterial colonization of chronic skin ulcers independently from the multidrug resistant phenotype

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    Bacterial biofilm is a major factor in delayed wound healing and high levels of biofilm production have been repeatedly described in multidrug resistant organisms (MDROs). Nevertheless, a quantitative correlation between biofilm production and the profile of antimicrobial drug resistance in delayed wound healing remains to be determined. Microbial identification, antibiotic susceptibility and biofilm production were assessed in 135 clinical isolates from 87 patients. Gram-negative bacteria were the most represented microorganisms (60.8%) with MDROs accounting for 31.8% of the total isolates. Assessment of biofilm production revealed that 80% of the strains were able to form biofilm. A comparable level of biofilm production was found with both MDRO and not-MDRO with no significant differences between groups. All the methicillin-resistant Staphylococcus aureus (MRSA) and 80% of Pseudomonas aeruginosa MDR strains were found as moderate/high biofilm producers. Conversely, less than 17% of Klebsiella pneumoniae extended-spectrum beta-lactamase (ESBL), Escherichia coli-ESBL and Acinetobacter baumannii were moderate/high biofilm producers. Notably, those strains classified as non-biofilm producers, were always associated with biofilm producer bacteria in polymicrobial colonization. This study shows that biofilm producers were present in all chronic skin ulcers, suggesting that biofilm represents a key virulence determinant in promoting bacterial persistence and chronicity of ulcerative lesions independently from the MDRO phenotype

    Development and distribution of the non-indigenous Pacific oyster (Crassostrea gigas) in the Dutch Wadden Sea

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    Pacific oysters (Crassostrea gigas) were first observed in the Dutch Wadden Sea near Texel in 1983. The population increased slowly in the beginning but grew exponentially from the mid-1990s onwards, although now some stabilisation seems to be occurring. They occur on a variety of substrates such as mussel beds (Mytilus edulis), shell banks, dikes and poles. After initial settlement spat may fall on older individuals and congregate to dense clumps and subsequently form reefs. Individual Pacific oysters grow 3–4 cm long in their first year and 2–3 cm in their second year. Many mussel beds (Mytilus edulis) are slowly taken over by Pacific oysters, but there are also several reports of mussel spat settling on Pacific oyster reefs. This might in the end result in combined reefs. Successful Pacific oyster spat fall seems to be related to high summer temperatures, but also after mild summers much spat can be found on old (Pacific oyster) shells. Predation is of limited importance. Mortality factors are unknown, but every now and then unexplained mass mortality occurs. The gradual spread of the Pacific oyster in the Dutch Wadden Sea is documented in the first instance based on historical and anecdotal information. At the start of the more in-depth investigation in 2002, Pacific oysters of all size classes were already present near Texel. Near Ameland the development could be followed from the first observed settlement. On dense reefs each square metre may contain more than 500 adult Pacific oysters, weighing more than 100 kg per m² fresh weigh

    Importance of the solvation degree of peptide-resin beads for amine groups determination by the picric acid method

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    The classic and important picric acid method used in polymers biochemical and chemical fields of polymers for amine group quantification was chosen in this work as a model for evaluating the influence of the resin bead solvation during an analytical procedure. It was observed that this method, proposed almost three decades ago, failed to quantify amine groups of peptidyl-resin containing aggregating and polar sequence. This was due to inefficient solvation of resin beads when only CH2Cl2 was used for picrate anion binding and subsequent washing steps. It was demonstrated that the use of CH2Cl2/DMF (dimethylformamide) and CH2Cl2/EtOH solutions during these steps allows correct determination of peptidyl-resin amine groups. Besides the importance for the solid phase peptide synthesis methodology itself, these findings also represent the first quantitative demonstration of the relationship between solvation degree and the efficiency of a polymer-supported analytical method.O clássico e importante método do ácido pícrico, usado nas áreas de bioquímica e química de polímeros para a quantificação de grupos aminos, foi escolhido neste trabalho como modelo para investigar a importância do grau de solvatação de grãos poliméricos durante o protocolo analítico. Verificou-se que este método, proposto há cerca de três décadas atrás, falha na quantificação de grupos amino de peptidil-resinas contendo seqüência agregante e polar. Isto ocorre devido à solvatação insuficiente dos grãos quando apenas o CH2Cl2 é utilizado na etapa de ligação do ânion picrato e na subsequente etapa de lavagem. Demonstrou-se que a utilização nestas etapas, de soluções de CH2Cl2/DMF (dimetilformamida) e de CH2Cl2/EtOH permite uma determinação correta dos grupos amínicos de peptídil-resinas. Além da importância em si para o método da síntese de peptídeos em fase sólida, estes resultados representam também a primeira comprovação experimental da correlação quantitativa existente entre o grau de solvatação e a eficiência de um método analítico efetuado em grãos de resinas.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Federal de São Paulo (UNIFESP) Departamento de BiofísicaUNIFESP, Depto. de BiofísicaSciEL

    Effects of miRNA-15 and miRNA-16 expression replacement in chronic lymphocytic leukemia : implication for therapy

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    This work was supported by: Associazione Italiana Ricerca sul Cancro (AIRC) Grant 5 x mille n.9980, (to M.F., F.M. A. N., P.T. and M.N.) ; AIRC I.G. n. 14326 (to M.F.), n.10136 and 16722 (A.N.), n.15426 (to F.F.). AIRC and Fondazione CaRiCal co-financed Multi Unit Regional Grant 2014 n.16695 (to F.M.). Italian Ministry of Health 5x1000 funds (to S.Z. and F.F). A.G R. was supported by Associazione Italiana contro le Leucemie-Linfomi-Mielomi (AIL) Cosenza - Fondazione Amelia Scorza (FAS). S.M. C.M., M.C., L.E., S.B. were supported by AIRC.Peer reviewedPostprin

    Development of a peptide ELISA for the diagnosis of Equine arteritis virus

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    A peptide-based indirect ELISA was developed to detect antibodies against Equine arteritis virus (EAV). Two peptides for epitope C of protein GP5 and fragment E of protein M were designed, synthesized, purified and used as antigens either alone or combined. Ninety-two serum samples obtained from the 2010 Equine viral arteritis outbreak, analyzed previously by virus neutralization, were evaluated by the ELISA here developed. The best resolution was obtained using peptide GP5. The analysis of the inter- and intraplate variability showed that the assay was robust. The results allow concluding that this peptide-based ELISA is a good alternative to the OIE-prescribed virus neutralization test because it can be standardized between laboratories, can serve as rapid screening, can improve the speed of diagnosis of EAV-negative horses and can be particularly useful for routine surveillance in large populations.Fil: Metz, German Ernesto. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología. Cátedra de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lorenzon, Esteban Nicolás. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Serena, Maria Soledad. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología. Cátedra de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Corva, Santiago Gerardo. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Cátedra de Epidemiología; ArgentinaFil: Panei, Carlos Javier. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología. Cátedra de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Diaz, Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; ArgentinaFil: Maffud Cilli, Eduardo. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Echeverria, Maria Gabriela. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Departamento de Microbiología. Cátedra de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentin

    Kajian Perbedaan Konsentrasi Larutan Garam Pada Perendaman Rgh Dan Vaksin Terhadap Kelulushidupan Dan Pertumbuhan Benih Ikan Lele Sangkuriang (Clarias Gariepinus)

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    Berdasarkan data KKP (2013), pencapaian produksi ikan lele pada tahun 2013 mampu melampaui target. Ikan lele merupakan ikan yang mudah dibudidayakan, sehingga banyak dilakukan penelitian agar didapatkan benih lele dengan pertumbuhan dan kelulushidupan yang lebih baik, serta tahan terhadap serangan penyakit. Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi larutan garam yang berbeda dan konsentrasi yang terbaik pada perendaman rGH dan vaksin terhadap kelulushidupan dan pertumbuhan benih lele sangkuriang. Penelitian ini dilaksanakan pada tanggal 13 November 2014 – 15 Februari 2015 di Satuan Kerja Pembenihan dan Budidaya Ikan Air Tawar (SATKER PBIAT), Siwarak, Ungaran, Semarang. Ikan uji yang digunakan adalah benih lele sangkuriang umur 12 hari. Metode yang digunakan adalah eksperimental dengan rancangan acak lengkap (RAL) 4 perlakuan dan 3 ulangan, yaitu: (A) perlakuan tanpa larutan garam, (B) konsentrasi 0,5%, (C) konsentrasi 1,0% dan (D) konsentrasi 1,5%. Pemeliharaan ikan dilakukan selama 42 hari. Variabel data yang diamati meliputi kelulushidupan, SGR, panjang mutlak, FCR, EPP dan kelulushidupan setelah uji tantang. Analisa data dengan menggunakan anova untuk mengetahui pengaruh perlakuan yang berbeda nyata, apabila hasil yang didapatkan berbeda nyata, maka dilanjutkan dengan uji duncan untuk mengetahui perlakuan yang terbaik. Hasil penelitian menunjukkan perlakuan terbaik adalah perlakuan C, dengan nilai kelulushidupan (87,00±1,00%), SGR (7,79±0,03%), nilai panjang mutlak (6,75±0,15cm), nilai FCR (0,71±0,01) dan nilai EPP (140,28±1,25%), sedangkan untuk kelulushidupan setelah uji tantang didapatkan hasil yang tidak berbeda nyata, dimana: A (93,33±5,77%), B (96,67±5,77%), C (96,67±5,77%) dan D (96,67±5,77%). Kesimpulan dari penelitian ini ialah pemberian konsentrasi larutan garam yang berbeda berpengaruh sangat nyata terhadap kelulushidupan, SGR, panjang mutlak, FCR dan EPP, namun tidak berpengaruh nyata terhadap kelulushidupan setelah uji tantang. Konsentrasi larutan garam terbaik pada penelitian ini adalah 1,0%. Based on data from KKP (2013), the achievement of the production of catfish in 2013 was able of exceeding the target. Catfish is a fish that easily cultivated, so a lot of research done to get catfish\u27s seed with better survival and growth, and it can resistant to attack of deseases. This research was aimed to find out the effect of different salt solution concentrations and the best concentration from immersion of rGH and vaccine for survival rate and growth of sangkuriang catfish\u27s seed. This research was conducted on November 13th, 2014 – February 15th, 2015 at Satuan Kerja Pembenihan dan Budidaya Ikan Air Tawar (SATKER PBIAT), Siwarak, Ungaran, Semarang. The fish that used for this research is sangkuriang catfish\u27s seed aged 12 days. Completely randomized design (CRD) was used in this research with four treatments and three replication, which treatments are: (A) without salt solution concentration, (B) Using concentration 0.5%, (C) Concentration 1.0% and (D) Concentration 1.5%. The Fishes are maintained for 42 days. Observational variable are survival rate, SGR, absolute length, FCR, EPP and survival rate after challenge test. Data analysis using anova to know the effect of treatment is significantly different, if the result is significantly different, then continue with duncan test to know the best treatment. The best result is treatment C, with survival rate (87.00±1.00%), SGR (7.79±0.03%), absolute length (6.75±0.15cm), FCR (0.71±0.01), EPP (140.28±1.25%), and for survival rate after challenge test are not significantly different, where: treatment A (93.33±5.77%), B (96.67±5.77%), C (96.67±5.77%) and D (96.67±5.77%). The conclusion of this research is giving of salt solution with different concentration take significantly effect for survival rate, SGR, absolute length, FCR and EPP, but did not take significantly effect for survival rate after challenge test. The best salt solution concentration is 1.0%

    A non-invasive approach to monitor chronic lymphocytic leukemia engraftment in a xenograft mouse model using ultra-small superparamagnetic iron oxide-magnetic resonance imaging (USPIO-MRI).

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    This work was supported by: Associazione Italiana Ricerca sul Cancro (AIRC) [Grant 5 x mille n.9980, (to M.F., F.M. and A. N.)]; AIRC I.G. [n. 14,326 (to M.F.)], [n.10136 and 16,722 (A.N.)], [n.15426 (to F.F.)]. AIRC and Fondazione CaRiCal co-financed Multi Unit Regional Grant 2014 [n.16695 (to F.M.)]. Italian Ministry of Health 5 × 1000 funds (to F.F). A.G R. was supported by Associazione Italiana contro le Leucemie-Linfomi-Mielomi (AIL) Cosenza - Fondazione Amelia Scorza (FAS). S.M. C.M., F.V., L. E., S. B., were supported by AIRC.Peer reviewedPostprin

    Editorial Note

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    Editor\u27s Note for Volume 23, Issue 2 of theTrotter Review

    Impacts of Inquiry Pedagogy on Undergraduate Students Conceptions of the Function of Proof

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    Mathematicians and mathematics educators agree that proof is an important tool in mathematics, yet too often undergraduate students see proof as a superficial part of the discipline. While proof is often used by mathematicians to justify that a theorem is true, many times proof is used for another purpose entirely such as to explain why a particular statement is true or to show mathematics students a particular proof technique. This paper reports on a study that used a form of inquiry-based learning (IBL) in an introduction to proof course and measured the beliefs of students in this course about the different functions of proof in mathematics as compared to students in a non-IBL course. It was found that undergraduate students in an introduction to proof course had a more robust understanding of the functions of proof than previous studies would suggest. Additionally, students in the course taught using inquiry pedagogy were more likely to appreciate the communication, intellectual challenge, and providing autonomy functions of proof. It is hypothesized that these results are a response to the pedagogy of the course and the types of student activity that were emphasized
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