Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Int J Mol Sci ; 25(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38673944

RESUMO

It is important to search for cytostatic compounds in order to fight cancer. One of them could be 2'-methylthiamine, which is a thiamine antimetabolite with an additional methyl group at the C-2 carbon of thiazole. So far, the cytostatic potential of 2'-methylthiamine has not been studied. We have come forward with a simplified method of synthesis using commercially available substrates and presented a comparison of its effects, as boosted by oxythiamine, on normal skin fibroblasts and HeLa cancer cells, having adopted in vitro culture techniques. Oxythiamine has been found to inhibit the growth and metabolism of cancer cells significantly better than 2'-methylthiamine (GI50 36 and 107 µM, respectively), while 2'-methylthiamine is more selective for cancer cells than oxythiamine (SI = 180 and 153, respectively). Docking analyses have revealed that 2'-methylthiamine (ΔG -8.2 kcal/mol) demonstrates a better affinity with thiamine pyrophosphokinase than thiamine (ΔG -7.5 kcal/mol ) and oxythiamine (ΔG -7.0 kcal/mol), which includes 2'-methylthiamine as a potential cytostatic. Our results suggest that the limited effect of 2'-methylthiamine on HeLa arises from the related arduous transport as compared to oxythiamine. Given that 2'-methylthiamine may possibly inhibit thiamine pyrophosphokinase, it could once again be considered a potential cytostatic. Thus, research should be carried out in order to find the best way to improve the transport of 2'-methylthiamine into cells, which may trigger its cytostatic properties.


Assuntos
Simulação de Acoplamento Molecular , Oxitiamina , Humanos , Células HeLa , Oxitiamina/farmacologia , Oxitiamina/química , Oxitiamina/metabolismo , Tiamina/farmacologia , Tiamina/análogos & derivados , Tiamina/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Simulação por Computador
2.
Chemphyschem ; 25(6): e202400184, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488206

RESUMO

The front cover artwork is provided by Dr habil. Izabella Jastrzebska's group from the University of Bialystok, Poland. The image shows a polymeric network with molecular rotors (MR) as crosslinks. The MR rotation is slowed or inhibited when a molecule of stored gas is placed inside the polymer material. Read the full text of the Research Article at 10.1002/cphc.202300793.

3.
Chemphyschem ; 25(6): e202300793, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38259120

RESUMO

In this paper, we report a new generation of polymeric networks as potential functional material based on changes in molecular dynamics in the solid state. The material is obtained by free radical polymerization of a diacrylate derivative bearing a steroid (stator) and a 1,4-diethynyl-phenylene-d4 fragment (rotator). Polymer research using the PALS technique complements the knowledge about nanostructural changes occurring in the system in the temperature range -115 °C - +190 °C. It indicates the presence of two types of free nanovolumes in the system and the occurrence of phase transitions. The polymer is characterized using 1 H NMR, 2 H Solid Echo NMR, ATR-FTIR and Raman spectroscopies, thermal analysis, and porosimetry. It is proved that the applied procedure leads to the formation of a novel porous organic material containing multiple molecular rotors.

4.
Plant Methods ; 20(1): 8, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216953

RESUMO

BACKGROUND: In drought periods, water use efficiency depends on the capacity of roots to extract water from deep soil. A semi-field phenotyping facility (RadiMax) was used to investigate above-ground and root traits in spring barley when grown under a water availability gradient. Above-ground traits included grain yield, grain protein concentration, grain nitrogen removal, and thousand kernel weight. Root traits were obtained through digital images measuring the root length at different depths. Two nearest-neighbor adjustments (M1 and M2) to model spatial variation were used for genetic parameter estimation and genomic prediction (GP). M1 and M2 used (co)variance structures and differed in the distance function to calculate between-neighbor correlations. M2 was the most developed adjustment, as accounted by the Euclidean distance between neighbors. RESULTS: The estimated heritabilities ([Formula: see text]) ranged from low to medium for root and above-ground traits. The genetic coefficient of variation ([Formula: see text]) ranged from 3.2 to 7.0% for above-ground and 4.7 to 10.4% for root traits, indicating good breeding potential for the measured traits. The highest [Formula: see text] observed for root traits revealed that significant genetic change in root development can be achieved through selection. We studied the genotype-by-water availability interaction, but no relevant interaction effects were detected. GP was assessed using leave-one-line-out (LOO) cross-validation. The predictive ability (PA) estimated as the correlation between phenotypes corrected by fixed effects and genomic estimated breeding values ranged from 0.33 to 0.49 for above-ground and 0.15 to 0.27 for root traits, and no substantial variance inflation in predicted genetic effects was observed. Significant differences in PA were observed in favor of M2. CONCLUSIONS: The significant [Formula: see text] and the accurate prediction of breeding values for above-ground and root traits revealed that developing genetically superior barley lines with improved root systems is possible. In addition, we found significant spatial variation in the experiment, highlighting the relevance of correctly accounting for spatial effects in statistical models. In this sense, the proposed nearest-neighbor adjustments are flexible approaches in terms of assumptions that can be useful for semi-field or field experiments.

6.
Front Plant Sci ; 14: 1258100, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37810388

RESUMO

Epichloë spp. often form mutualistic interactions with cool-season grasses, such as Lolium perenne. However, the molecular mechanisms underlying this interaction remain poorly understood. In this study, we employed reduced representation bisulfite sequencing method (epiGBS) to investigate the impact of the Epichloë sp. LpTG-3 strain AR37 on the methylome of L. perenne across multiple grass generations and under drought stress conditions. Our results showed that the presence of the endophyte leads to a decrease in DNA methylation across genomic features, with differentially methylated regions primarily located in intergenic regions and CHH contexts. The presence of the endophyte was consistently associated with hypomethylation in plants across generations. This research sheds new light on the molecular mechanisms governing the mutualistic interaction between Epichloë sp. LpTG-3 strain AR37 and L. perenne. It underscores the role of methylation changes associated with endophyte infection and suggests that the observed global DNA hypomethylation in L. perenne may be influenced by factors such as the duration of the endophyte-plant association and the accumulation of genetic and epigenetic changes over time.

7.
Pharmaceutics ; 15(4)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37111543

RESUMO

In recent years, there has been a significant surge in reports on the health-promoting benefits of winter cherry (Withania somnifera), also known as Ashwagandha. Its current research covers many aspects of human health, including neuroprotective, sedative and adaptogenic effects and effects on sleep. There are also reports of anti-inflammatory, antimicrobial, cardioprotective and anti-diabetic properties. Furthermore, there are reports of reproductive outcomes and tarcicidal hormone action. This growing body of research on Ashwagandha highlights its potential as a valuable natural remedy for many health concerns. This narrative review delves into the most recent findings and provides a comprehensive overview of the current understanding of ashwagandha's potential uses and any known safety concerns and contraindications.

8.
Plants (Basel) ; 11(17)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36079572

RESUMO

Whole-genome multi-omics profiles contain valuable information for the characterization and prediction of complex traits in plants. In this study, we evaluate multi-omics models to predict four complex traits in barley (Hordeum vulgare); grain yield, thousand kernel weight, protein content, and nitrogen uptake. Genomic, transcriptomic, and DNA methylation data were obtained from 75 spring barley lines tested in the RadiMax semi-field phenomics facility under control and water-scarce treatment. By integrating multi-omics data at genomic, transcriptomic, and DNA methylation regulatory levels, a higher proportion of phenotypic variance was explained (0.72-0.91) than with genomic models alone (0.55-0.86). The correlation between predictions and phenotypes varied from 0.17-0.28 for control plants and 0.23-0.37 for water-scarce plants, and the increase in accuracy was significant for nitrogen uptake and protein content compared to models using genomic information alone. Adding transcriptomic and DNA methylation information to the prediction models explained more of the phenotypic variance attributed to the environment in grain yield and nitrogen uptake. It furthermore explained more of the non-additive genetic effects for thousand kernel weight and protein content. Our results show the feasibility of multi-omics prediction for complex traits in barley.

9.
Plant Genome ; 15(4): e20253, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35975565

RESUMO

The growing demand for food and feed crops in the world because of growing population and more extreme weather events requires high-yielding and resilient crops. Many agriculturally important traits are polygenic, controlled by multiple regulatory layers, and with a strong interaction with the environment. In this study, 120 F2 families of perennial ryegrass (Lolium perenne L.) were grown across a water gradient in a semifield facility with subsoil irrigation. Genomic (single-nucleotide polymorphism [SNP]), transcriptomic (gene expression [GE]), and DNA methylomic (MET) data were integrated with feed quality trait data collected from control and drought sections in the semifield facility, providing a treatment effect. Deep root length (DRL) below 110 cm was assessed with convolutional neural network image analysis. Bayesian prediction models were used to partition phenotypic variance into its components and evaluated the proportion of phenotypic variance in all traits captured by different regulatory layers (SNP, GE, and MET). The spatial effects and effects of SNP, GE, MET, the interaction between GE and MET (GE × MET) and GE × treatment (GEControl and GEDrought ) interaction were investigated. Gene expression explained a substantial part of the genetic and spatial variance for all the investigated phenotypes, whereas MET explained residual variance not accounted for by SNPs or GE. For DRL, MET also contributed to explaining spatial variance. The study provides a statistically elegant analytical paradigm that integrates genomic, transcriptomic, and MET information to understand the regulatory mechanisms of polygenic effects for complex traits.


Assuntos
Lolium , Lolium/genética , Herança Multifatorial , Metilação de DNA , Teorema de Bayes , Genótipo , Transcriptoma
10.
J Enzyme Inhib Med Chem ; 37(1): 876-894, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35296203

RESUMO

With increasing number of immunocompromised patients as well as drug resistance in fungi, the risk of fatal fungal infections in humans increases as well. The action of echinocandins is based on the inhibition of ß-(1,3)-d-glucan synthesis that builds the fungal cell wall. Caspofungin, micafungin, anidulafungin and rezafungin are semi-synthetic cyclic lipopeptides. Their specific chemical structure possess a potential to obtain novel derivatives with better pharmacological properties resulting in more effective treatment, especially in infections caused by Candida and Aspergillus species. In this review we summarise information about echinocandins with closer look on their chemical structure, mechanism of action, drug resistance and usage in clinical practice. We also introduce actual trends in modification of this antifungals as well as new methods of their administration, and additional use in viral and bacterial infections.


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Candida/efeitos dos fármacos , Desenho de Fármacos , Equinocandinas/farmacologia , Antifúngicos/química , Aspergillus/metabolismo , Candida/metabolismo , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Equinocandinas/química , Glucanos/antagonistas & inibidores , Glucanos/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular
11.
Int J Mol Sci ; 22(22)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34830061

RESUMO

It is established that high rates of morbidity and mortality caused by fungal infections are related to the current limited number of antifungal drugs and the toxicity of these agents. Imidazolium salts as azole derivatives can be successfully used in the treatment of fungal infections in humans. Steroid-functionalized imidazolium salts were synthesized using a new, more efficient method. As a result, 20 salts were obtained with high yields, 12 of which were synthesized and characterized for the first time. They were derivatives of lithocholic acid and 3-oxo-23,24-dinorchol-4-ene-22-al and were fully characterized by 1H and 13C nuclear magnetic resonance (NMR), infrared spectroscopy (IR), and high resolution mass spectrometry (HRMS). Due to the excellent activity against bacteria and Candida albicans, new research was extended to include tests on five species of pathogenic fungi and molds: Aspergillus niger ATCC 16888, Aspergillus fumigatus ATCC 204305, Trichophyton mentagrophytes ATCC 9533, Cryptococcus neoformans ATCC 14116, and Microsporum canis ATCC 11621. The results showed that the new salts are almost universal antifungal agents and have a broad spectrum of activity against other human pathogens. To initially assess the safety of the synthesized salts, hemocompatibility with host cells and cytotoxicity were also examined. No toxicity was observed at the concentration at which the compounds were active against pathogens.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Imidazóis/farmacologia , Esteroides/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Bactérias/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fungos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Imidazóis/síntese química , Imidazóis/química , Micoses/tratamento farmacológico , Sais/síntese química , Sais/química , Sais/farmacologia , Esteroides/síntese química , Esteroides/química
12.
Genes (Basel) ; 13(1)2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-35052360

RESUMO

A population of 239 perennial ryegrass (Lolium perenne L.) genotypes was analyzed to identify marker-trait associations for crown rust (Puccinia coronata f. sp. lolii) and brown rust (Puccinia graminis f. sp. loliina) resistance. Phenotypic data from field trials showed a low correlation (r = 0.17) between the two traits. Genotypes were resequenced, and a total of 14,538,978 SNPs were used to analyze population structure, linkage disequilibrium (LD), and for genome-wide association study. The SNP heritability (h2SNP) was 0.4 and 0.8 for crown and brown rust resistance, respectively. The high-density SNP dataset allowed us to estimate LD decay with the highest possible precision to date for perennial ryegrass. Results showed a low LD extension with a rapid decay of r2 value below 0.2 after 520 bp on average. Additionally, QTL regions for both traits were detected, as well as candidate genes by applying Genome Complex Trait Analysis and Multi-marker Analysis of GenoMic Annotation. Moreover, two significant genes, LpPc6 and LpPl6, were identified for crown and brown rust resistance, respectively, when SNPs were aggregated to the gene level. The two candidate genes encode proteins with phosphatase activity, which putatively can be induced by the host to perceive, amplify and transfer signals to downstream components, thus activating a plant defense response.


Assuntos
Resistência à Doença/genética , Lolium/genética , Doenças das Plantas/genética , Basidiomycota/patogenicidade , Mapeamento Cromossômico/métodos , Estudo de Associação Genômica Ampla/métodos , Genótipo , Desequilíbrio de Ligação/genética , Lolium/microbiologia , Fenótipo , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único/genética , Puccinia/patogenicidade , Locos de Características Quantitativas/genética
13.
Plant Genome ; 13(3): e20049, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33217208

RESUMO

Patterns and level of cytosine methylation vary widely among plant species and are associated with genome size as well as the proportion of transposons and other repetitive elements in the genome. We explored epigenetic patterns and diversity in a representative proportion of the spring barley (Hordeum vulgare L.) genome across several commercial and historical cultivars. This study adapted a genotyping-by-sequencing (GBS) approach for the detection of methylated cytosines in genomic DNA. To analyze the data, we developed WellMeth, a complete pipeline for analysis of reduced representation bisulfite sequencing. WellMeth enabled quantification of context-specific DNA methylation at the single-base resolution as well as identification of differentially methylated sites (DMCs) and regions (DMRs). On average, DNA methylation levels were significantly higher than what is commonly observed in many plants species, reaching over 10-fold higher levels than those in Arabidopsis thaliana (L.) Heynh. in the CHH methylation. Preferential methylation was observed within and at the edges of long-terminal repeats (LTR) retrotransposons Gypsy and Copia. From a pairwise comparison of cultivars, numerous DMRs could be identified of which more than 5,000 were conserved within the analyzed set of barley cultivars. The subset of regions overlapping with genes showed enrichment in gene ontology (GO) categories associated with chromatin and cellular structure and organization. A significant correlation between genetic and epigenetic distances suggests that a considerable portion of methylated regions is under strict genetic control in barley. The data presented herein represents the first step in efforts toward a better understanding of genome-level structural and functional aspects of methylation in barley.


Assuntos
Metilação de DNA , Hordeum , Citosina , Hordeum/genética , Sulfitos
14.
Am J Physiol Heart Circ Physiol ; 319(2): H306-H319, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32618513

RESUMO

Dilated cardiomyopathy (DCM) is clinically characterized by dilated ventricular cavities and reduced ejection fraction, leading to heart failure and increased thromboembolic risk. Mutations in thin-filament regulatory proteins can cause DCM and have been shown in vitro to reduce contractility and myofilament Ca2+-affinity. In this work we have studied the functional consequences of mutations in cardiac troponin T (R131W), cardiac troponin I (K36Q) and α-tropomyosin (E40K) using adenovirally transduced isolated guinea pig left ventricular cardiomyocytes. We find significantly reduced fractional shortening with reduced systolic Ca2+. Contraction and Ca2+ reuptake times were slowed, which contrast with some findings in murine models of myofilament Ca2+ desensitization. We also observe increased sarcoplasmic reticulum (SR) Ca2+ load and smaller fractional SR Ca2+ release. This corresponds to a reduction in SR Ca2+-ATPase activity and increase in sodium-calcium exchanger activity. We also observe dephosphorylation and nuclear translocation of the nuclear factor of activated T cells (NFAT), with concordant RAC-α-serine/threonine protein kinase (Akt) phosphorylation but no change to extracellular signal-regulated kinase activation in chronically paced cardiomyocytes expressing DCM mutations. These changes in Ca2+ handling and signaling are common to all three mutations, indicating an analogous pathway of disease pathogenesis in thin-filament sarcomeric DCM. Previous work has shown that changes to myofilament Ca2+ sensitivity caused by DCM mutations are qualitatively opposite from hypertrophic cardiomyopathy (HCM) mutations in the same genes. However, we find several common pathways such as increased relaxation times and NFAT activation that are also hallmarks of HCM. This suggests more complex intracellular signaling underpinning DCM, driven by the primary mutation.NEW & NOTEWORTHY Dilated cardiomyopathy (DCM) is a frequently occurring cardiac disorder with a degree of genetic inheritance. We have found that DCM mutations in proteins that regulate the contractile machinery cause alterations to contraction, calcium-handling, and some new signaling pathways that provide stimuli for disease development. We have used guinea pig cells that recapitulate human calcium-handling and introduced the mutations using adenovirus gene transduction to look at the initial triggers of disease before remodeling.


Assuntos
Sinalização do Cálcio , Cardiomiopatia Dilatada/genética , Proteínas dos Microfilamentos/genética , Mutação , Contração Miocárdica , Miócitos Cardíacos/enzimologia , Fatores de Transcrição NFATC/metabolismo , Proteína Oncogênica v-akt/metabolismo , Função Ventricular Esquerda , Animais , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/fisiopatologia , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/metabolismo , Cardiomiopatia Hipertrófica/fisiopatologia , Células Cultivadas , Predisposição Genética para Doença , Cobaias , Masculino , Proteínas dos Microfilamentos/metabolismo , Fenótipo , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Tropomiosina/genética , Tropomiosina/metabolismo , Troponina I/genética , Troponina I/metabolismo , Troponina T/genética , Troponina T/metabolismo
15.
J Steroid Biochem Mol Biol ; 189: 65-72, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30797035

RESUMO

Imidazolium salts reveal interesting biological properties, especially regarding antitumor and antimicrobial activities. Two series of imidazolium salts based on steroids were obtained in an efficient and convenient synthesis. They were biologically tested to evaluate their antibacterial and antifungal properties. The activities of new salts, especially in relation to Gram-positive bacterial strains are comparable to the activities of known antibiotics. The most promising activity was that against C. albicans, which exceeded the antifungal activity of commonly used drugs. Some of the new salts exhibited improved antifungal activities against phytopathogenic fungi: B. cinerea and C. beticola. Our research showed that new compounds could be potentially useful as antifungal antibiotics or inhibiting agents against pathogenic fungi.


Assuntos
Anti-Infecciosos/farmacologia , Imidazóis/farmacologia , Esteroides/farmacologia , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Técnicas de Química Sintética , Fungos/efeitos dos fármacos , Humanos , Imidazóis/síntese química , Imidazóis/química , Micoses/tratamento farmacológico , Sais/síntese química , Sais/química , Sais/farmacologia , Esteroides/síntese química , Esteroides/química
16.
J Hum Lact ; 35(2): 371-380, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30571929

RESUMO

BACKGROUND: Extended breastfeeding is rare in Poland, and lack of acceptance and understanding is often evident in public opinion. The ability to provide reliable information about breastfeeding beyond infancy depends on health professionals' levels of knowledge and attitudes. They are considered by most parents in Poland to be authorities in the field of child nutrition. RESEARCH AIMS: To determine (1) the level of knowledge and the attitudes of Polish health professionals towards extended breastfeeding; (2) the relationship between personal breastfeeding experience and attitudes towards extended breastfeeding; and (3) the relationship between knowledge about breastfeeding beyond twelve months and attitudes towards breastfeeding beyond infancy. METHODS: A one-group prospective, cross-sectional, self-report style survey was used. The convenience sample ( N = 495) comprised gynaecologists, neonatologists and midwives. Data were collected via an online questionnaire and the results were analyzed with the use of descriptive statistics, a chi-square independence test, Fisher's exact test, post-hoc testing, and two-part tables using SPSS. RESULTS: Most of the respondents (76.7%; n = 384) had a low level of knowledge about the benefits of breastfeeding beyond twelve months and even emphasized that this nutritional choice could have negative impacts. There was a positive correlation ( F = 105.847; p = < .01) between levels of knowledge and respondents' attitudes towards breastfeeding beyond infancy. Attitudes were also influenced by the length of time respondents had breastfed. CONCLUSION: Healthcare providers have an insufficient level of knowledge about extended breastfeeding and need further education in this area.


Assuntos
Atitude Frente a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde/estatística & dados numéricos , Mães/estatística & dados numéricos , Papel Profissional , Adulto , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Polônia , Estudos Prospectivos , Opinião Pública
17.
Tree Physiol ; 38(3): 320-339, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28541580

RESUMO

Wood is a renewable resource that can be employed for the production of second generation biofuels by enzymatic saccharification and subsequent fermentation. Knowledge on how the saccharification potential is affected by genotype-related variation of wood traits and drought is scarce. Here, we used three Populus nigra L. genotypes from habitats differing in water availability to (i) investigate the relationships between wood anatomy, lignin content and saccharification and (ii) identify genes and co-expressed gene clusters related to genotype and drought-induced variation in wood traits and saccharification potential. The three poplar genotypes differed in wood anatomy, lignin content and saccharification potential. Drought resulted in reduced cambial activity, decreased vessel and fiber lumina, and increased the saccharification potential. The saccharification potential was unrelated to lignin content as well as to most wood anatomical traits. RNA sequencing of the developing xylem revealed that 1.5% of the analyzed genes were differentially expressed in response to drought, while 67% differed among the genotypes. Weighted gene correlation network analysis identified modules of co-expressed genes correlated with saccharification potential. These modules were enriched in gene ontology terms related to cell wall polysaccharide biosynthesis and modification and vesicle transport, but not to lignin biosynthesis. Among the most strongly saccharification-correlated genes, those with regulatory functions, especially kinases, were prominent. We further identified transcription factors whose transcript abundances differed among genotypes, and which were co-regulated with genes for biosynthesis and modifications of hemicelluloses and pectin. Overall, our study suggests that the regulation of pectin and hemicellulose metabolism is a promising target for improving wood quality of second generation bioenergy crops. The causal relationship of the identified genes and pathways with saccharification potential needs to be validated in further experiments.


Assuntos
Secas , Genótipo , Populus/anatomia & histologia , Populus/genética , Madeira/anatomia & histologia , Madeira/metabolismo , Expressão Gênica , Genes de Plantas , Hidrólise , Lignina/metabolismo , Família Multigênica , Polissacarídeos/metabolismo , Populus/metabolismo
18.
Monatsh Chem ; 147: 1091-1100, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27340298

RESUMO

ABSTRACT: New indenylidene-type second generation catalysts bearing modified unsymmetrically substituted N-heterocyclic carbene ligands were synthesized. The complexes contain an N-mesityl and N'-nitrobenzyl substituted NHC ligand. The precursors of free carbenes-imidazolinium salts-were obtained in an easy and environment-friendly way (under aqueous or neat conditions). The new catalysts were prepared by reaction of in situ generated carbenes with a 1st generation indenylidene catalyst, containing pyridine ligands instead of tricyclohexylphosphine. The complexes were tested in RCM, CM, and ene-yne metathesis model reactions in commercial-grade solvents in air. Their activities were compared with that of commercially available indenylidene catalyst. The structures of complexes and their stability were investigated using static DFT calculations with mixed basis set.

19.
Int Urogynecol J Pelvic Floor Dysfunct ; 18(6): 619-26, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17031489

RESUMO

We compared inflammatory response, fibrosis and biomechanical properties of different polypropylene materials from one manufacturer (Tyco Healthcare) in a rat model for primary fascial repair. Full-thickness abdominal wall defects were primarily repaired using 'overlay' technique. Multifilament implants were Surgipro SPM and SPMW, the latter a wider-weave type of the former. Monofilament SPMM implants and polypropylene suture repair (Surgipro II) served as controls. Explants were evaluated macroscopically and changes in thickness, shrinkage and tensile strength were measured. Inflammatory and connective tissue response was assessed on haematoxylin-eosin and Movat stains. Immunohistochemistry was done to localise rat macrophages/monocytes. Multifilament materials induced a shorter acute inflammatory response and more pronounced chronic inflammatory reaction compared to monofilament implants. Macrophages could be found deep in interstices 7.5 by 12.5 microm. No difference in collagen deposition and neovascularisation was observed. At 90 days time point, explants reconstructed with tighter woven multifilament SPM were weaker than sutured or SPMM controls. Overall shrinkage of 10% was comparable for all groups.


Assuntos
Parede Abdominal/cirurgia , Materiais Biocompatíveis/uso terapêutico , Fasciotomia , Inflamação/etiologia , Polipropilenos/imunologia , Telas Cirúrgicas , Animais , Materiais Biocompatíveis/efeitos adversos , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Teste de Materiais , Polipropilenos/uso terapêutico , Ratos , Ratos Wistar , Suturas/efeitos adversos , Resistência à Tração , Prolapso Uterino/cirurgia , Cicatrização
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA