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1.
Colorectal Dis ; 25(12): 2423-2457, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37926920

RESUMO

AIM: The management of anal fissure: ACPGBI position statement was written 15 years ago. [KLR Cross et al., Colorectal Dis, 2008]. Our aim was to update the guideline and provide recommendations on the most effective treatment for patients with anal fissures utilising a multidisciplinary, rigorous guideline methodology. METHODS: The development process consisted of six phases. In phase 1 we defined the scope of the guideline. The patient population included patients with acute and chronic anal fissure. The target group was all practitioners (primary and secondary care) treating patients with fissures and, in addition, healthcare workers and patients who desired information regarding fissure management. In phase 2 we formed a guideline development group (GDG) including a methodologist. In phase 3 review questions were formulated, using a reversed PICO process, starting with possible recommendations based on the GDG's knowledge. In phase 4 a comprehensive literature search focused on existing systematic reviews addressing each review question, supplemented by more recent studies if appropriate. In phase 5 data were extracted from the included papers and checked by the GDG. If indicated, meta-analysis of systematic review data was updated by the GDG. During phase 6 the GDG members decided what recommendations could be made based on the evidence in the literature and strength of the recommendation was assessed using 'grade'. RESULTS: This guideline is divided into two sections: Primary care which includes (i) diagnosis; (ii) basic treatment; (iii) topical treatment; and secondary care which includes (iv) botulinum toxin therapy; (v) surgical intervention and (vi) special situations (including pregnancy and breast-feeding patients, children, receptive anal intercourse and low-pressure fissures). A total of 23 recommendations were formulated. A new term clinically healed was described by the GDG. CONCLUSION: This guideline provides an up-to-date evidence-based summary of the current knowledge of the management of anal fissure and may serve as a useful guide for clinicians as well as a potential reference for patients.


Assuntos
Fissura Anal , Criança , Humanos , Doença Crônica , Fissura Anal/cirurgia , Resultado do Tratamento , Reino Unido
2.
Curr Opin Clin Nutr Metab Care ; 26(6): 497-507, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37610824

RESUMO

PURPOSE OF REVIEW: Nutrition remains a key focus in the preoptimization of patients undergoing cancer surgery. Given the catabolic nature of cancer, coupled with the physiological insult of surgery, malnutrition (when assessed) is prevalent in a significant proportion of patients. Therefore, robust research on interventions to attenuate the detrimental impact of this is crucial. RECENT FINDINGS: As a unimodal prehabilitation intervention, assessment for malnutrition is the first step, as universal supplementation has not been shown to have a significant impact on outcomes. However, targeted nutritional therapy, whether that is enteral or parenteral, has been shown to improve the nutritional state of patients' presurgery, potentially reducing the rate of postoperative complications such as nosocomial infections. As part of multimodal prehabilitation, the situation is more nuanced given the difficulty in attribution of effects to the differing components, and vast heterogeneity in intervention and patient profiles. SUMMARY: Multimodal prehabilitation is proven to improve length of hospital stay and postoperative outcomes, with nutrition forming a significant part of the therapy given. Further work is required to look at not only the interplay between the optimization of nutritional status and other prehabilitation interventions, but also how to best select which patients will achieve significant benefit.

3.
Age Ageing ; 51(6)2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35737600

RESUMO

BACKGROUND: Declines in cardiorespiratory fitness (CRF) and muscle mass are both associated with advancing age and each of these declines is associated with worse health outcomes. Resistance exercise training (RET) has previously been shown to improve muscle mass and function in the older population. If RET is also able to improve CRF, as it has been shown to do in younger populations, it has the potential to improve multiple health outcomes in the expanding older population. METHODS: This systematic review aimed to identify the role of RET for improving CRF in healthy older adults. A search across CINAHL, MEDLINE, EMBASE and EMCARE databases was conducted with meta-analysis performed on eligible papers to identify improvements in established CRF parameters (VO2 peak, aerobic threshold (AT), 6-minute walking distance test (6MWT) following RET intervention. Main eligibility criteria included older adults (aged over 60), healthy cohorts (disease-specific cohorts were excluded) and RET intervention. RESULTS: Thirty-seven eligible studies were identified. Meta-analysis revealed a significant improvement in VO2 peak (MD 1.89 ml/kg/min; 95% confidence interval (CI) 1.21-2.57 ml/kg/min), AT (MD 1.27 ml/kg/min; 95% CI 0.44-2.09 ml/kg/min) and 6MWT (MD 30.89; 95% CI 26.7-35.08) in RET interventions less than 24 weeks. There was no difference in VO2 peak or 6MWT in interventions longer than 24 weeks. DISCUSSION: This systematic review adds to a growing body of evidence supporting the implementation of RET in the older population for improving whole-body health, particularly in time-limited timeframes.


Assuntos
Aptidão Cardiorrespiratória , Doenças Musculares , Treinamento Resistido , Idoso , Exercício Físico/fisiologia , Terapia por Exercício , Nível de Saúde , Humanos
4.
J Inorg Biochem ; 224: 111541, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34416481

RESUMO

The tyrosinase-like activity of hybrid guanidine-stabilized bis(µ-oxido) dicopper(III) complexes [Cu2(µ-O)2(L)2](X)2 (L = 2-{2-((Diethylamino)methyl)phenyl}-1,1,3,3-tetramethylguanidine (TMGbenzNEt2, L2) and 2-{2-((Di-isopropylamino)methyl)phenyl}-1,1,3,3-tetramethylguanidine (TMGbenzNiPr2, L3); X = PF6-, BF4-, CF3SO3-) is described. New aromatic hybrid guanidine amine ligands were developed with varying amine donor function. Their copper(I) complexes were analyzed towards their ability to activate dioxygen in the presence of different weakly coordinating anions. The resulting bis(µ-oxido) species were characterized at low temperatures by UV/Vis and resonance Raman spectroscopy, cryo-ESI mass spectrometry and density functional theory calculations. Small structural changes in the ligand sphere were found to influence the characteristic ligand-to-metal charge transfer (LMCT) features of the bis(µ-oxido) species, correlating a redshift in the UV/Vis spectrum with weaker N-donor function of the ligand. DFT calculations elucidated the influence of the steric and electronic properties of the bis(µ-oxido) species leading to a higher twist of the Cu2O2 plane against the CuN2 plane and a stretching of the Cu2O2 core. Despite their moderate stability at -100 °C, the bis(µ-oxido) complexes exhibited a remarkable activity in catalytic oxygenation reactions of polycyclic aromatic alcohols. Further the selectivity of the catalyst in the hydroxylation reactions of challenging phenolic substrates is not changed despite an increasing shield of the reactive bis(µ-oxido) core. The generated quinones were found to form exclusively bent phenazines, providing a promising strategy to access tailored phenazine derivatives.


Assuntos
Cobre/química , Guanidina/química , Monofenol Mono-Oxigenase/metabolismo , Compostos Organometálicos/química , Oxigênio/química , Álcoois/química , Aminas/química , Hidroxiquinolinas/química , Ligantes , Espectroscopia de Ressonância Magnética/métodos , Modelos Moleculares , Estrutura Molecular , Naftóis/química , Análise Espectral Raman/métodos
5.
J Biol Inorg Chem ; 26(2-3): 249-263, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33595752

RESUMO

Inspired by the efficiency of natural enzymes in organic transformation reactions, the development of synthetic catalysts for oxygenation and oxidation reactions under mild conditions still remains challenging. Tyrosinases serve as archetype when it comes to hydroxylation reactions involving molecular oxygen. We herein present new copper(I) guanidine halide complexes, capable of the activation of molecular oxygen at room temperature. The formation of the reactive bis(µ-oxido) dicopper(III) species and the influence of the anion are investigated by UV/Vis spectroscopy, mass spectrometry, and density functional theory. We highlight the catalytic hydroxylation activity towards diverse polycyclic aromatic alcohols under mild reaction conditions. The selective formation of reactive quinones provides a promising tool to design phenazine derivatives for medical applications.


Assuntos
Azulenos/química , Complexos de Coordenação/química , Cobre/química , Oxigênio/química , Sesquiterpenos de Guaiano/química , Temperatura , Teoria da Densidade Funcional , Modelos Moleculares , Conformação Molecular
6.
Chemistry ; 26(34): 7556-7562, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32104930

RESUMO

The enzyme tyrosinase contains a reactive side-on peroxo dicopper(II) center as catalytically active species in C-H oxygenation reactions. The tyrosinase activity of the isomeric bis(µ-oxo) dicopper(III) form has been discussed controversially. The synthesis of bis(µ-oxo) dicopper(III) species [Cu2 (µ-O)2 (L1)2 ](X)2 ([O1](X)2 , X=PF6 - , BF4 - , OTf- , ClO4 - ), stabilized by the new hybrid guanidine ligand 2-{2-((dimethylamino)methyl)phenyl}-1,1,3,3-tetramethylguanidine (L1), and its characterization by UV/Vis, Raman, and XAS spectroscopy, as well as cryo-UHR-ESI mass spectrometry, is described. We highlight selective oxygenation of a plethora of phenolic substrates mediated by [O1](PF6 )2 , which results in mono- and bicyclic quinones and provides an attractive strategy for designing new phenazines. The selectivity is predicted by using the Fukui function, which is hereby introduced into tyrosinase model chemistry. Our bioinspired catalysis harnesses molecular dioxygen for organic transformations and achieves a substrate diversity reaching far beyond the scope of the enzyme.

7.
New Phytol ; 225(4): 1715-1731, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31596965

RESUMO

Arabidopsis thaliana contains 13 fibrillins (FBNs), which are all localized to chloroplasts. FBN1 and FBN2 are involved in photoprotection of photosystem II, and FBN4 and FBN5 are thought to be involved in plastoquinone transport and biosynthesis, respectively. The functions of the other FBNs remain largely unknown. To gain insight into the function of FBN6, we performed coexpression and Western analyses, conducted fluorescence and transmission electron microscopy, stained reactive oxygen species (ROS), measured photosynthetic parameters and glutathione levels, and applied transcriptomics and metabolomics. Using coexpression analyses, FBN6 was identified as a photosynthesis-associated gene. FBN6 is localized to thylakoid and envelope membranes, and its knockout results in stunted plants. The delayed-growth phenotype cannot be attributed to altered basic photosynthesis parameters or a reduced CO2 assimilation rate. Under moderate light stress, primary leaves of fbn6 plants begin to bleach and contain enlarged plastoglobules. RNA sequencing and metabolomics analyses point to an alteration in sulfate reduction in fbn6. Indeed, glutathione content is higher in fbn6, which in turn confers cadmium tolerance of fbn6 seedlings. We conclude that loss of FBN6 leads to perturbation of ROS homeostasis. FBN6 enables plants to cope with moderate light stress and affects cadmium tolerance.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Cloroplastos/metabolismo , Fibrilinas/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Aclimatação/genética , Aclimatação/fisiologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Cádmio/toxicidade , Proteínas de Cloroplastos/genética , Fibrilinas/genética , Homeostase , Luz , Fotossíntese/fisiologia , Transporte Proteico , Estresse Fisiológico/efeitos dos fármacos , Sulfatos/metabolismo , Tilacoides/fisiologia
8.
Dalton Trans ; 48(3): 1017-1022, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30574969

RESUMO

A series of zero-valent palladium complexes featuring diphosphinometal ligands is reported. The metalloligand in the PMP-type framework (M = LiI, CuI, ZnII) acts as a weak to medium acceptor ligand for palladium. A Pd0→ZnII bond was observed in the solid state and further confirmed by NBO analysis. The heterobimetallic Pd/Zn complex 2-Zn displayed excellent activity in chemoselective CO2 hydrosilylation producing silyl formate (TOF1/2 = 3000 h-1).

9.
Proc Natl Acad Sci U S A ; 115(51): E12101-E12110, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30509981

RESUMO

Plant response to environmental stimuli involves integration of multiple signals. Upon low-oxygen stress, plants initiate a set of adaptive responses to circumvent an energy crisis. Here, we reveal how these stress responses are induced by combining (i) energy-dependent changes in the composition of the acyl-CoA pool and (ii) the cellular oxygen concentration. A hypoxia-induced decline of cellular ATP levels reduces LONG-CHAIN ACYL-COA SYNTHETASE activity, which leads to a shift in the composition of the acyl-CoA pool. Subsequently, we show that different acyl-CoAs induce unique molecular responses. Altogether, our data disclose a role for acyl-CoAs acting in a cellular signaling pathway in plants. Upon hypoxia, high oleoyl-CoA levels provide the initial trigger to release the transcription factor RAP2.12 from its interaction partner ACYL-COA BINDING PROTEIN at the plasma membrane. Subsequently, according to the N-end rule for proteasomal degradation, oxygen concentration-dependent stabilization of the subgroup VII ETHYLENE-RESPONSE FACTOR transcription factor RAP2.12 determines the level of hypoxia-specific gene expression. This research unveils a specific mechanism activating low-oxygen stress responses only when a decrease in the oxygen concentration coincides with a drop in energy.


Assuntos
Acil Coenzima A/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Estresse Fisiológico , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Hipóxia Celular , Inibidor da Ligação a Diazepam/metabolismo , Regulação da Expressão Gênica de Plantas , Modelos Biológicos , Oxigênio/metabolismo , Transdução de Sinais
10.
Chemistry ; 23(62): 15738-15745, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-28850743

RESUMO

The electron-transfer abilities of the copper guanidinoquinoline (GUAqu) complexes [Cu(TMGqu)2 ]+/2+ and [Cu(DMEGqu)2 ]+/2+ (TMGqu=tetramethylguanidinoquinoline, DMEGqu=dimethylethylguanidinoquinoline) were examined in different solvents. The determination of the electron self-exchange rate based on the Marcus theory reveals the highest electron-transfer rate of copper complexes with pure N-donor ligands (k11 =1.2×104  s-1 m-1 in propionitrile). This is supported by an examination of the reorganisation energy of the complexes by using Eyring theory and DFT calculations. The low reorganisation energies in nitrile solvents correspond with the high electron-transfer rates of the complexes. Therefore, the [Cu(GUAqu)2 ]+/2+ complexes act as good entatic states model of copper enzymes. The structural influence of the complexes on the kinetic parameters shows that the TMGqu system possesses a higher electron-transfer rate than DMEGqu. Supporting DFT calculations give a closer insight into the kinetics and thermodynamics (Nelsen's four-point method and isodesmic reactions) of the electron transfer.


Assuntos
Complexos de Coordenação/química , Cobre/química , Modelos Moleculares , Quinolinas/química , Transporte de Elétrons , Cinética , Ligantes , Nitrilas/química , Oxirredução , Solventes/química , Espectrofotometria , Termodinâmica
11.
Mol Plant ; 10(4): 575-589, 2017 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-28062321

RESUMO

The translocon on the outer membrane of mitochondria (TOM) facilitates the import of nuclear-encoded proteins. The principal machinery of mitochondrial protein transport seems conserved in eukaryotes; however, divergence in the composition and structure of TOM components has been observed between mammals, yeast, and plants. TOM9, the plant homolog of yeast Tom22, is significantly smaller due to a truncation in the cytosolic receptor domain, and its precise function is not understood. Here we provide evidence showing that TOM9.2 from Arabidopsis thaliana is involved in the formation of mature TOM complex, most likely by influencing the assembly of the pore-forming subunit TOM40. Dexamethasone-induced RNAi gene silencing of TOM9.2 results in a severe reduction in the mature TOM complex, and the assembly of newly imported TOM40 into the complex is impaired. Nevertheless, mutant plants are fully viable and no obvious downstream effects of the loss of TOM complex, i.e., on mitochondrial import capacity, were observed. Furthermore, we found that TOM9.2 can bind calmodulin (CaM) in vitro and that CaM impairs the assembly of TOM complex in the isolated wild-type mitochondria, suggesting a regulatory role of TOM9.2 and a possible integration of TOM assembly into the cellular calcium signaling network.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Ligação a Calmodulina/metabolismo , Proteínas de Transporte/metabolismo , Proteínas Mitocondriais/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Sinalização do Cálcio/genética , Sinalização do Cálcio/fisiologia , Proteínas de Ligação a Calmodulina/genética , Proteínas de Transporte/genética , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Proteínas Mitocondriais/genética , Transporte Proteico/genética , Transporte Proteico/fisiologia
12.
Plant Physiol ; 172(1): 141-53, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27372243

RESUMO

Subgroup-VII-ethylene-response-factor (ERF-VII) transcription factors are involved in the regulation of hypoxic gene expression and regulated by proteasome-mediated proteolysis via the oxygen-dependent branch of the N-end-rule pathway. While research into ERF-VII mainly focused on their role to regulate anoxic gene expression, little is known on the impact of this oxygen-sensing system in regulating plant metabolism and growth. By comparing Arabidopsis (Arabidopsis thaliana) plants overexpressing N-end-rule-sensitive and insensitive forms of the ERF-VII-factor RAP2.12, we provide evidence that oxygen-dependent RAP2.12 stability regulates central metabolic processes to sustain growth, development, and anoxic resistance of plants. (1) Under normoxia, overexpression of N-end-rule-insensitive Δ13RAP2.12 led to increased activities of fermentative enzymes and increased accumulation of fermentation products, which were accompanied by decreased adenylate energy states and starch levels, and impaired plant growth and development, indicating a role of oxygen-regulated RAP2.12 degradation to prevent aerobic fermentation. (2) In Δ13RAP2.12-overexpressing plants, decreased carbohydrate reserves also led to a decrease in anoxic resistance, which was prevented by external Suc supply. (3) Overexpression of Δ13RAP2.12 led to decreased respiration rates, changes in the levels of tricarboxylic acid cycle intermediates, and accumulation of a large number of amino acids, including Ala and γ-amino butyric acid, indicating a role of oxygen-regulated RAP2.12 abundance in controlling the flux-modus of the tricarboxylic acid cycle. (4) The increase in amino acids was accompanied by increased levels of immune-regulatory metabolites. These results show that oxygen-sensing, mediating RAP2.12 degradation is indispensable to optimize metabolic performance, plant growth, and development under both normoxic and hypoxic conditions.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Metaboloma , Metabolômica/métodos , Oxigênio/metabolismo , Fatores de Transcrição/metabolismo , Aerobiose , Aminoácidos/metabolismo , Anaerobiose , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Biomassa , Ciclo do Ácido Cítrico , Proteínas de Ligação a DNA , Etilenos/metabolismo , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Regulação da Expressão Gênica de Plantas , Mutação , Consumo de Oxigênio/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sacarose/metabolismo , Fatores de Transcrição/genética
13.
Nat Commun ; 6: 8009, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26284300

RESUMO

Cell-based therapy exploits modified human cells to treat diseases but its targeted application in specific tissues, particularly those lying deep in the body where direct injection is not possible, has been problematic. Here we use a magnetic resonance imaging (MRI) system to direct macrophages carrying an oncolytic virus, Seprehvir, into primary and metastatic tumour sites in mice. To achieve this, we magnetically label macrophages with super-paramagnetic iron oxide nanoparticles and apply pulsed magnetic field gradients in the direction of the tumour sites. Magnetic resonance targeting guides macrophages from the bloodstream into tumours, resulting in increased tumour macrophage infiltration and reduction in tumour burden and metastasis. Our study indicates that clinical MRI scanners can not only track the location of magnetically labelled cells but also have the potential to steer them into one or more target tissues.


Assuntos
Compostos Férricos/administração & dosagem , Macrófagos/fisiologia , Nanopartículas Metálicas/administração & dosagem , Neoplasias da Próstata/terapia , Animais , Permeabilidade Capilar , Terapia Baseada em Transplante de Células e Tecidos , Células Cultivadas , Meios de Contraste , Gadolínio DTPA , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Neoplasias Experimentais/terapia , Vírus Oncolíticos , Distribuição Aleatória , Transplante Heterólogo
14.
Bioorg Med Chem Lett ; 21(10): 2991-7, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21486695

RESUMO

The identification of two novel series of formyl peptide receptor 1 (FPR1) antagonists are reported, represented by methionine benzimidazole 6 and diamide 7. Both series specifically inhibited the binding of labelled fMLF to hrFPR1 and selectively antagonized FPR1 function in human neutrophils, making them useful in vitro validation tools for the target.


Assuntos
Descoberta de Drogas , Receptores de Formil Peptídeo/antagonistas & inibidores , Receptores de Formil Peptídeo/química , Humanos , Estrutura Molecular
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