1,188 research outputs found
Manejo de resĆduo vegetal de plantas de cobertura de inverno sobre plantas invasoras e soja, sob condiƧƵes controladas, em casa de vegetaĆ§Ć£o
In order to meet the great need to increase agricultural yield associated with the research of healthy products, which do not cause problems for the environment, this study aims to investigate the influence of mass quantity on black oats, radish and hairy deer in the emergence and development of B. pilosa, S. rhombifolia and G. max. It was carried out in the greenhouse with 10, 20, 30, 40 or 50 g of the studied weights. The weed and soybean seeds were sown and evaluated for 10 days to record their emergence. For the initial development of plants, five seedlings were transplanted, which evaluation occurred after 30 days. In general, increasing the amount of weight also increased the percentage inhibition of the weeds studied, but did not negatively influence the soybean. ESI (Emergence Speed Index) and ES (emergence speed) were negatively affected by the increase in weight, with the exception of soy ES. Weed mass was negatively influenced by cover crops, but did not cause problems for soybeans. Thus, the greatest amount of mass in relation to the winter cover crops studied was lower, being the infestation of these weeds without significant problems for the soybean. Finally, species may be recommended for further field studies as cover crops in large areas in the no-tillage system.Visando suprir a crescente necessidade de incremento na produĆ§Ć£o agrĆcola, associada Ć” busca por produtos saudĆ”veis e que nĆ£o agridam ao ambiente, este trabalho teve por objetivo verificar a influĆŖncia da quantidade de massa de aveia preta, nabo forrageiro e ervilhaca peluda sobre emergĆŖncia, Ćndice de velocidade de emergĆŖncia (IVE), velocidade de emergĆŖncia (VE), massa fresca e seca de parte aĆ©rea e raiz de picĆ£o preto, guanxuma e soja. O experimento foi desenvolvido em casa de vegetaĆ§Ć£o, em vasos contendo aproximadamente 1 kg de solo, sobre os quais foram depositadas 10, 20, 30, 40 ou 50 g (equivalentes a 17; 33; 50; 66 e 83 kg ha-1) das massas estudadas. Para avaliaĆ§Ć£o da emergĆŖncia, as sementes das espĆ©cies invasoras e soja foram semeadas e avaliadas durante 10 dias, com contagem diĆ”ria. Para desenvolvimento inicial de planta, foram transplantadas cinco plĆ¢ntulas para cada vaso, com avaliaĆ§Ć£o apĆ³s 30 dias. De modo geral, o aumento na quantidade de massa aumentou a porcentagem de inibiĆ§Ć£o de guanxuma e picĆ£o preto, mas nĆ£o influenciou negativamente a soja. O IVE e VE das espĆ©cies foram afetados negativamente com o aumento da quantidade das massas, exceto para VE de soja. As massas das invasoras foi influenciada negativamente pelas plantas de cobertura, sem entretanto, prejudicar a soja. Assim, quanto maior a quantidade de massa das espĆ©cies de cobertura de inverno utilizadas, menor serĆ” a infestaĆ§Ć£o dessas invasoras, sem prejuĆzos significativos Ć” soja. Por fim, as espĆ©cies podem ser recomendadas para maiores estudos em campo como culturas de cobertura em grandes Ć”reas no sistema de plantio direto.Facultad de Ciencias Agrarias y Forestale
Synthesis of Peptaibolin, an antimicrobial peptide
To tackle one of the biggest global health problems, the resistance of microorganisms to
antibiotics, a collective effort in the search for more effective agents against bacteria was required.
Peptides with antimicrobial activity have been raising much attention as a promising alternative for
antibiotics. Peptaibols, for instance, are a family of antimicrobial peptides (AMPs) with great
biomedical potential, in which the Peptaibolin can be highlighted. This peptide has gained relevance
due to its small amino acids content, only four, and its acetyl group and a phenylalaninol residue
(Phol) at the N-terminal and C-terminal, respectively. Here, we report the synthesis of Peptaibolin
through Solid Phase Peptide Synthesis assisted by Microwave heating (MW-SPPS) in a pre-loaded
Phe-Wang resin. Starting from a loading of 0.51 mmol/g, two syntheses were made, using two
different combinations of coupling reagents. The best option was DIC/Oxima, achieving a yield of
50.0%. Proton Nuclear Magnetic Resonance (1H-NMR) studies confirmed the peptide structure,
while High Performance Liquid Chromatography (HPLC) verified the peptide purity. The peptide
solubility was examined against several combinations of solvents. Peptaibolin was not soluble in
water, only in organic solvents or in the combination of both. Antimicrobial testing was conducted
using Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa.
Minimum inhibitory concentration studies demonstrated the resistance of bacteria to the peptide
action and the peptide instability in bacterial growth conditionsFundaĆ§Ć£o para a CiĆŖncia e Tecnologia-FCT (Portugal) for funding through CQUM (UID/QUI/00686/2020) and project PTDC/QUI-COL/28052/2017. The NMR
spectrometer Bruker Avance III 400 is part of the National NMR Network and was purchased within
the framework of the National Program for Scientific Re-equipment, contract REDE/1517/RMN/2005
with funds from POCI 2010 (FEDER) and FCT. Authors also acknowledge FCT for funding the project PEPTEX with reference PTDC/CTM-TEX/28074/2017 (POCI-01-0145-FEDER-028074). They
acknowledge project UID/CTM/00264/2021 of Centre for Textile Science and Technology (2C2T),
funded by national funds through FCT/MCTE
Deri yara kaplamalarindaki uygulamalar iƧin elektrik alan lif Ƨekim ile Ć¼retilmiÅ Tiger 17 peptit yĆ¼klĆ¼ polikaprolakton/selĆ¼loz asetat nano lifli matlar
A skin wound if not properly treated can result in a chronic wound susceptible to widespread infections, which can result
in the patient's death. Currently, tissue engineering is described as an interdisciplinary field that combines principles of engineering,
chemistry and biology to generate solutions that allow to repair, restore and/or improve the functions of injured tissues. In the same
sense, the textile area addresses solutions based on polymeric fibers, produced from a wide range of polymers, which allow the
generation of structures with a large surface area, porosity and mechanical resistance that can be used as bioactive dressings that promote
a healing and efficient antimicrobial activity. This research work focused on the synthesis of Tiger 17, through microwave-assisted
solid-phase synthesis methodologies, and Tiger 17 commercially obtained, respective structural characterization and evaluation of the
antimicrobial capacity. Simultaneously, nanofibrous polymer matrices were produced using the electrospinning technique with the aim
of immobilizing the developed biomolecule and thus creating potential vehicles for a local and sustainable antimicrobial action
(controlled release). In order to verify its physical and chemical properties, advanced characterization techniques were used: proton
nuclear magnetic resonance, high performance liquid chromatography, optical microscopy, scanning electron microscopy, fourier
transform infrared spectroscopyāattenuated total reflectance, thermogravimetry, differential scanning calorimetry, contact angle and
surface energy and determination of porosity and hydration.DĆ¼zgĆ¼n tedavi edilmeyen bir cilt yarası, hastanın ƶlĆ¼mĆ¼yle sonuƧlanabilecek yaygın enfeksiyonlara duyarlı kronik bir yaraya neden
olabilir. GĆ¼nĆ¼mĆ¼zde doku mĆ¼hendisliÄi, hasarlı dokuların iÅlevlerini onarmaya, eski haline getirmeye ve/veya iyileÅtirmeye olanak
tanıyan ƧƶzĆ¼mler Ć¼retmek iƧin mĆ¼hendislik, kimya ve biyolojinin ilkelerini birleÅtiren disiplinler arası bir alan olarak tanımlanmaktadır.
Bu kapsamda, tekstil, iyileÅmeyi ve etkili antimikrobiyal aktiviteyi teÅvik eden biyoaktif pansuman olarak kullanılabilecek, geniÅ yĆ¼zey
alanlı, gƶzenekli ve mekanik direnƧli yapıların oluÅturulmasına izin veren, geniÅ bir polimer yelpazesinden Ć¼retilen liflere dayalı
ƧƶzĆ¼mler sunmaktadır. Bu araÅtırma ƧalıÅması, mikrodalga destekli katı faz sentez metodolojileri aracılıÄıyla Tiger 17'nin sentezine ve
ticari olarak temin edilen Tiger 17 ile birlikte yapısal karakterizasyonunun ve antimikrobiyal kapasitenin deÄerlendirilmesine
odaklanmıÅtır. Aynı zamanda, geliÅtirilen biyomolekĆ¼lĆ¼ hareketsiz hale getirmek ve bƶylece lokal ve sĆ¼rdĆ¼rĆ¼lebilir bir antimikrobiyal
etki (kontrollĆ¼ salım) iƧin potansiyel ƧƶzĆ¼mler yaratmak amacıyla elektrik alan lif Ć¼retim tekniÄi kullanılarak nanolifli polimer matrisler
Ć¼retildi. Yapının fiziksel ve kimyasal ƶzelliklerini doÄrulamak iƧin, proton nĆ¼kleer manyetik rezonans, yĆ¼ksek performanslı sıvı
kromatografisi, optik mikroskopi, taramalı elektron mikroskobu, fourier dƶnĆ¼ÅĆ¼mĆ¼ kızılƶtesi spektroskopisi-zayıflatılmıŠtoplam
yansıma, termogravimetri, diferansiyel taramalı kalorimetri, temas aƧısı, yĆ¼zey enerjisi, gƶzeneklilik ve su tutma ƶlĆ§Ć¼mleri gibi ileri
karakterizasyon teknikleri kullanıldı
Aqueous biphasic systems composed of ionic liquids: one-step extraction/concentration techniques for water pollution tracers
Emergent micropollutants have become a serious global problem with a large impact in the environment and
human health, while their presence in aquatic systems has been registered as ranging from ng/L-1 to ug/L-1.
Pharmaceuticals are ubiquitous micropollutants since their continuous consumption and consequent release via
human excretions into aqueous systems are inevitable. Due to their usually low concentrations in aqueous
samples, the development of a pre-concentration technique in order to continuously quantify and to monitor these
components in aqueous streams is of major relevance.
Aqueous biphasic systems (ABS) composed of ionic liquids (ILs) can be seen as more sustainable separation
processes since they avoid the use of volatile and hazardous organic solvents (VOCs). As liquid-liquid
systems, ABS can be used as extraction, purification and concentration platforms. Due to the outstanding tunable
properties of ILs, IL-based ABS provide higher and more selective extraction efficiencies for a wide range of
compounds when compared to traditional polymer-based ABS. IL-based ABS were already employed and
adequately characterized for the extraction and concentration of endocrine disruptors, either from biological fluids
or aqueous matrices. The aim of this work is to demonstrate the applicability of IL-based ABS to completely
extract and concentrate, in one-step, two different and representative pharmaceutical pollution tracers, namely
caffeine (CAF) and carbamazepine (CBZ). The low concentration of these persistent pollutants (usually found in
ug/L-1 and ng/L-1 levels) does not allow a proper detection and quantification by conventional analytical
equipment without a previous concentration step. However, pre-concentration methods commonly applied are
costly, time-consuming, provide irregular recoveries and/or use VOCs. In this work, ABS composed of the IL
tetrabutylammonium chloride ([N4444]Cl) and the salt K3C6H5O7 was investigated, demonstrating to be able to
completely extract and concentrate CAF and CBZ in a single-step. Moreover, with this pre-treatment step it was
demonstrated to be possible to overcome the detection limits of a high performance liquid chromatography
coupled to an UV-Vis detector equipment. The results obtained demonstrate that IL-based ABS are
versatile pre-concentration techniques, and can be used for the extraction and concentration of a large plethora of
other micropollutants from environmental aqueous matrices.publishe
Case Report: Pheochromocytoma and Synchronous Neuroblastoma in a Family With Hereditary Pheochromocytoma Associated With a MAX Deleterious Variant
Introduction: Pheochromocytomas are rare catecholamine-producing neuroendocrine tumours arising from chromaffin cells of the adrenal medulla or extra-adrenal sympathetic paraganglia. Recent studies have indicated that up to 40% of pheochromocytomas could be attributable to an inherited germline variant in an increasing list of susceptibility genes. Germline variants of the MYC-associated factor (MAX) gene have been associated with familial pheochromocytomas and paragangliomas with an autosomal dominant pattern of inheritance, a median age at onset of 33 years and an overall frequency estimated at 1.9%. We describe a deleterious MAX variant associated with hereditary pheochromocytoma in a family with four affected individuals.
Case presentation: The first patient presented with bilateral pheochromocytoma in 1995; genetic testing was proposed to his oldest son, when he was diagnosed with a bilateral pheochromocytoma with a synchronous neuroblastoma. Upon the identification of the MAX variant c.97C>T, p.(Arg33Ter), in the latter individual, his two siblings and their father were tested and the same variant was identified in all of them. Both siblings were subsequently diagnosed with pheochromocytoma (one of them bilateral) and choose to remain on active surveillance before they were submitted to adrenalectomy. All the tumours secreted predominantly norepinephrine, accordingly to the typical biochemical phenotype ascribed to variants in the MAX gene.
Conclusion: This case series is, to our knowledge, the one with the largest number of individuals with hereditary pheochromocytoma with a deleterious MAX variant in the same family. It is also the first case with a synchronous pheochromocytoma and neuroblastoma in carriers of a MAX deleterious variant. This report draws attention to some ill-defined features of pheochromocytoma and other malignancies associated with a MAX variant and highlights the importance of understanding the genotype-phenotype correlation in hereditary pheochromocytoma and the impact of oriented genetic testing to detect, survey and treat patients and kindreds at risk.N/
Atividades da crianƧa: educaĆ§Ć£o x liberdade x restriƧƵes
Este estudo teve por objetivo descrever e analisar o grau de liberdade de aĆ§Ć£o e escolha permitido pela mĆ£e nas atividades diĆ”rias e brincadeiras da crianƧa. Os dados foram obtidos atravĆ©s da anĆ”lise das respostas de 110 mĆ£es a 15 questƵes do Roteiro Reestruturado de Biasoli-Alves e Graminha (1979), que investigam as condiƧƵes oferecidas Ć crianƧa em termos de movimentaĆ§Ć£o e espaƧo fĆsico, determinaĆ§Ć£o de atividades e horĆ”rios, uso da casa, da TV, brincadeiras e brinquedo. Os resultados indicam que as mĆ£es procuram dar liberdade a seus filhos, mas tambĆ©m lhes colocam restriƧƵes, num padrĆ£o prĆ³ximo ao sugerido pela literatura psicolĆ³gica, o que nĆ£o deixa de implicar numa tutela coastante sobre a crianƧa.This study has meant to describe the level of freedom of action and of choice the mothers allow their children to have on their daily activities. Data was obtained by the analysis of the answers 110 mothers gave to 15 questions from the Biasoli-Alves & Graminha Reestructured Guide (1979), which investigate the conditions offered to the child in terms of physical space, delimitation of activities, use of home, TV set, play and toys. The results show that the mothers try to give freedom to their children in a similar pattern to the one the psychological literature suggests, as well as they set up restrictions, in a pattern of constant watchful care over the child
Anti-hepatocellular carcinoma activity using human HepG2 cells and hepatotoxicity of 6-substituted methyl 3-aminothieno[3,2-b]pyridine-2-carboxylate derivatives: in vitro evaluation, cell cycle analysis and QSAR studies
Hepatocellular carcinoma (HCC) is a highly complex cancer, resistant to commonly used treatments and new therapeutic agents are urgently needed. A total of thirty-two thieno[3,2-b]pyridine derivatives of two series: methyl 3-amino-6-(hetero)arylthieno[3,2-b]pyridine-2-carboxylates (1a-1t) and methyl 3-amino-6-[(hetero)arylethynyl]thieno[3,2-b]pyridine-2-carboxylates (2a-2n), previously prepared by some of us, were evaluated as new potential anti-HCC agents by studying their in vitro cell growth inhibition on human HepG2 cells and hepatotoxicity using a porcine liver primary cell culture (PLP1). The presence of amino groups linked to a benzene moiety emerges as the key element for the anti-HCC activity. The methyl 3-amino-6-[(3-aminophenyl)ethynyl]thieno[3,2-b]pyridine-2-carboxylate (2f) is the most potent compound presenting GI50 values on HepG2 cells of 1.2 Ī¼M compared to 2.9 Ī¼M of the positive control ellipticine, with no observed hepatotoxicity (PLP1 GI50>125 Ī¼M against 3.3 Ī¼M of ellipticine). Moreover this compound changes the cell cycle profile of the HepG2 cells, causing a decrease in the % of cells in the S phase and a cell cycle arrest in the G2/M phase. QSAR studies were also performed and the correlations obtained using molecular and 1D descriptors revealed the importance of the presence of amino groups and hydrogen bond donors for anti-HCC activity, and hydrogen bond acceptors for hepatotoxicity. The best correlations were obtained with 3D descriptors belonging to different subcategories for anti-HCC activity and hepatotoxicity, respectively. These results point to different molecular mechanisms of action of the compounds in anti-HCC activity and hepatotoxicity. This work presents some promising thieno[3,2-b]pyridine derivatives for potential use in the therapy of HCC. These compounds can also be used as scaffolds for further synthesis of more potent analogues.FCT, FEDER/COMPETE/QREN/E
No-match ORESTES explored as tumor markers
Sequencing technologies and new bioinformatics tools have led to the complete sequencing of various genomes. However, information regarding the human transcriptome and its annotation is yet to be completed. The Human Cancer Genome Project, using ORESTES (open reading frame EST sequences) methodology, contributed to this objective by generating data from about 1.2 million expressed sequence tags. Approximately 30% of these sequences did not align to ESTs in the public databases and were considered no-match ORESTES. On the basis that a set of these ESTs could represent new transcripts, we constructed a cDNA microarray. This platform was used to hybridize against 12 different normal or tumor tissues. We identified 3421 transcribed regions not associated with annotated transcripts, representing 83.3% of the platform. The total number of differentially expressed sequences was 1007. Also, 28% of analyzed sequences could represent noncoding RNAs. Our data reinforces the knowledge of the human genome being pervasively transcribed, and point out molecular marker candidates for different cancers. To reinforce our data, we confirmed, by real-time PCR, the differential expression of three out of eight potentially tumor markers in prostate tissues. Lists of 1007 differentially expressed sequences, and the 291 potentially noncoding tumor markers were provided
No-match ORESTES explored as tumor markers
Sequencing technologies and new bioinformatics tools have led to the complete sequencing of various genomes. However, information regarding the human transcriptome and its annotation is yet to be completed. The Human Cancer Genome Project, using ORESTES (open reading frame EST sequences) methodology, contributed to this objective by generating data from about 1.2 million expressed sequence tags. Approximately 30% of these sequences did not align to ESTs in the public databases and were considered no-match ORESTES. On the basis that a set of these ESTs could represent new transcripts, we constructed a cDNA microarray. This platform was used to hybridize against 12 different normal or tumor tissues. We identified 3421 transcribed regions not associated with annotated transcripts, representing 83.3% of the platform. The total number of differentially expressed sequences was 1007. Also, 28% of analyzed sequences could represent noncoding RNAs. Our data reinforces the knowledge of the human genome being pervasively transcribed, and point out molecular marker candidates for different cancers. To reinforce our data, we confirmed, by real-time PCR, the differential expression of three out of eight potentially tumor markers in prostate tissues. Lists of 1007 differentially expressed sequences, and the 291 potentially noncoding tumor markers were provided
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