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1.
J Hosp Infect ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38609760

RESUMO

The first British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS)-endorsed faecal microbiota transplant (FMT) guidelines were published in 2018. Over the past 5 years, there has been considerable growth in the evidence base (including publication of outcomes from large national FMT registries), necessitating an updated critical review of the literature and a second edition of the BSG/HIS FMT guidelines. These have been produced in accordance with National Institute for Health and Care Excellence-accredited methodology, thus have particular relevance for UK-based clinicians, but are intended to be of pertinence internationally. This second edition of the guidelines have been divided into recommendations, good practice points and recommendations against certain practices. With respect to FMT for Clostridioides difficile infection (CDI), key focus areas centred around timing of administration, increasing clinical experience of encapsulated FMT preparations and optimising donor screening. The latter topic is of particular relevance given the COVID-19 pandemic, and cases of patient morbidity and mortality resulting from FMT-related pathogen transmission. The guidelines also considered emergent literature on the use of FMT in non-CDI settings (including both gastrointestinal and non-gastrointestinal indications), reviewing relevant randomised controlled trials. Recommendations are provided regarding special areas (including compassionate FMT use), and considerations regarding the evolving landscape of FMT and microbiome therapeutics.

12.
Sci Data ; 6(1): 161, 2019 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-31467271

RESUMO

Sustained, quantitative observations of nearshore waves and sand levels are essential for testing beach evolution models, but comprehensive datasets are relatively rare. We document beach profiles and concurrent waves monitored at three southern California beaches during 2001-2016. The beaches include offshore reefs, lagoon mouths, hard substrates, and cobble and sandy (medium-grained) sediments. The data span two energetic El Niño winters and four beach nourishments. Quarterly surveys of 165 total cross-shore transects (all sites) at 100 m alongshore spacing were made from the backbeach to 8 m depth. Monthly surveys of the subaerial beach were obtained at alongshore-oriented transects. The resulting dataset consists of (1) raw sand elevation data, (2) gridded elevations, (3) interpolated elevation maps with error estimates, (4) beach widths, subaerial and total sand volumes, (5) locations of hard substrate and beach nourishments, (6) water levels from a NOAA tide gauge (7) wave conditions from a buoy-driven regional wave model, and (8) time periods and reaches with alongshore uniform bathymetry, suitable for testing 1-dimensional beach profile change models.

13.
Saudi J Biol Sci ; 25(8): 1622-1631, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30591779

RESUMO

Widely distributed in plants, flavonoids reduce the incidence of cancer and cardiovascular disease. In this study, flavonoid content and composition in members of the Prunus genus were evaluated using liquid chromatography with diode array and electrospray ionization mass spectrometric detection (UPLC-DAD-ESI/QTOF-MS). Flavonoids in plants of the Prunus genus include the basic structures of kaempferol, quercetin, and catechin, and exist as mono-, di-, or tri-glycoside compounds mono-acylated with acetic acid. A total of 23 individual flavonoids were isolated and confirmed, three of which appear to be newly identified compounds: quercetin 3-O-(2″-O-acetyl)neohesperidoside, quercetin 3-O-(4″-O-acetyl)rutinoside, and kaempferol 3-O-(4″-O-acetyl)rutinoside. Japanese apricot and Chinese plum contained the highest amounts of flavonoids in the Prunus genus. During the ripening stage of Japanese apricot, the total flavonol content was reduced, while the catechin content was increased.

14.
Adv Drug Deliv Rev ; 136-137: 2-27, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30359631

RESUMO

Current treatments for intestinal diseases including inflammatory bowel diseases, irritable bowel syndrome, and colonic bacterial infections are typically small molecule oral dosage forms designed for systemic delivery. The intestinal permeability hurdle to achieve systemic delivery from oral formulations of macromolecules is challenging, but this drawback can be advantageous if an intestinal region is associated with the disease. There are some promising formulation approaches to release peptides, proteins, antibodies, antisense oligonucleotides, RNA, and probiotics in the colon to enable local delivery and efficacy. We briefly review colonic physiology in relation to the main colon-associated diseases (inflammatory bowel disease, irritable bowel syndrome, infection, and colorectal cancer), along with the impact of colon physiology on dosage form design of macromolecules. We then assess formulation strategies designed to achieve colonic delivery of small molecules and concluded that they can also be applied some extent to macromolecules. We describe examples of formulation strategies in preclinical research aimed at colonic delivery of macromolecules to achieve high local concentration in the lumen, epithelial-, or sub-epithelial tissue, depending on the target, but with the benefit of reduced systemic exposure and toxicity. Finally, the industrial challenges in developing macromolecule formulations for colon-associated diseases are presented, along with a framework for selecting appropriate delivery technologies.


Assuntos
Colo/metabolismo , Doenças do Colo/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Substâncias Macromoleculares/administração & dosagem , Substâncias Macromoleculares/farmacocinética , Humanos , Substâncias Macromoleculares/uso terapêutico
15.
SAR QSAR Environ Res ; 29(10): 801-821, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30230355

RESUMO

The current study examines in silico characterization of the structure-inhibitory potency for a set of phenylcarbamic acid derivatives containing an N-arylpiperazine scaffold, considering the electronic, steric and lipophilic properties. The main objective of the ligand-based modelling was the systematic study of classical comparative molecular field analysis (CoMFA)/comparative molecular surface analysis (CoMSA) performance for the modelling of in vitro efficiency observed for these phenylcarbamates, revealing their inhibitory activities against a virulent Mycobacterium tuberculosis H37Rv strain. We compared the findings of efficiency modelling produced by a standard 3D methodology (CoMFA) and its neural counterparts (CoMSA) regarding multiple training/test subsets and variables used. Moreover, systematic space inspection, splitting values into the analysed training/test subsets, was performed to monitor statistical estimator performance while mapping the probability-driven pharmacophore pattern. Consequently, a 'pseudo-consensus' 3D-quantitative structure-activity relationship (3D-QSAR) approach was applied to retrieve an 'average' pharmacophore hypothesis by the investigation of the most densely populated training/test subpopulations to specify the potentially important factors contributing to the inhibitory activity of phenylcarbamic acid analogues. In addition, examination of descriptor-based similarity with a principal component analysis (PCA) procedure was employed to visualize noticeable variations in the performance of these molecules with respect to their structure and activity profiles.


Assuntos
Antibacterianos/farmacologia , Descoberta de Drogas , Modelos Moleculares , Mycobacterium tuberculosis/efeitos dos fármacos , Relação Quantitativa Estrutura-Atividade , Carbamatos/química , Simulação por Computador , Técnicas In Vitro , Ligantes , Probabilidade
16.
SAR QSAR Environ Res ; 28(6): 427-449, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28573881

RESUMO

Finding a balance between a desired drug's potency and its physicochemical properties that are important for its molecule pharmacokinetic or pharmacodynamics profile is still a challenging issue in rational drug discovery. Quantitative assessment of the lipophilic characteristics of potential drug molecules is indispensable for efficient development of Absorption, Distribution, Metabolism, Excretion, Toxicity-tailored structure-activity models; therefore reliable procedures for deriving log P from molecular structure are desirable. In the current work a range of various software log P predictors for estimation of the numerical lipophilic values for a set of cholic acid derivatives were employed and subsequently cross-compared with the experimental parameters. Thus, the empirical lipophilicity (RM) was compared with the corresponding log P characteristics calculated using alternative methods for deducing the lipophilic features. The mean values of the selected molecular descriptors that were averaged over the chosen calculation methods (consensus clog P) were subsequently correlated with the RM parameter. As an additional experiment, the iterative variable elimination partial least squares (IVE-PLS) methodology for an ensemble of descriptors retrieved from Dragon 6.0 software was applied for a set of drug transporters. To investigate the variations within the ensemble of cholic acid derivatives principal component analysis (PCA) and self-organizing neural network (SOM) procedures were used to visualize the major differences in the performance of drug promoters with respect to their lipophilic profile.


Assuntos
Ácidos Cólicos/química , Ácidos Cólicos/farmacocinética , Preparações Farmacêuticas/química , Adsorção , Química Farmacêutica/métodos , Simulação por Computador , Descoberta de Drogas/métodos , Interações Hidrofóbicas e Hidrofílicas , Análise dos Mínimos Quadrados , Lipídeos/química , Estrutura Molecular , Redes Neurais de Computação , Análise de Componente Principal , Relação Quantitativa Estrutura-Atividade
17.
J Dairy Sci ; 99(4): 2875-2883, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26830744

RESUMO

Housing lame cows in designated hospital pens with a soft surface may lessen the pain the animals feel when lying and changing position. This study investigated the effect of the lying surface on the behavior of lame cows in hospital pens. Thirty-two lame dairy cows were kept in individual hospital pens, provided with either 30-cm deep-bedded sand or 24-mm rubber mats during 24 h in a crossover design. On each surface, the lying behavior of each cow was recorded during 18 h. On deep-bedded sand, cows lay down more and changed position more often than when housed on the rubber surface. Furthermore, a shorter duration of lying down and getting up movements and a shorter duration of lying intention movements were observed. These results suggest that lame dairy cows are more reluctant to change position on rubber compared with sand, and that sand is more comfortable to lie on. Thus, deep bedding such as sand may provide better lying comfort for lame cows than an unbedded rubber surface.


Assuntos
Roupas de Cama, Mesa e Banho/veterinária , Comportamento Animal/fisiologia , Doenças dos Bovinos/terapia , Pisos e Cobertura de Pisos/normas , Coxeadura Animal , Borracha , Dióxido de Silício , Animais , Roupas de Cama, Mesa e Banho/normas , Bovinos , Feminino , Abrigo para Animais/normas , Coxeadura Animal/terapia , Fatores de Tempo
18.
Artigo em Inglês | MEDLINE | ID: mdl-26651713

RESUMO

This paper presents studies of dielectric response of chosen Schiff bases, which have similar molecular structures with different isomerizations of an azomethine bridging group, alkyloxy chain length with n=5 or n=6 carbon atoms, and a bromine or chlorine halogen terminal atom. Significant differences in the values of the maximum of dielectric absorption related to flip-flop molecular jumps in hexagonal smectic-B(Cry) phases have been found despite small differences of molecular dipole moments in these substances. This phenomenon is discussed in relation to the possibilities of the creation of dimers and to steric factors favoring motions.

19.
J Phys Chem B ; 118(51): 14982-9, 2014 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-25429851

RESUMO

The results of dielectric relaxation spectroscopy and polarizing microscope observation of the 4'-butyl-4-(2-methylbutoxy)azoxybenzene (abbreviated as 4ABO5*) are presented. Numerical analysis of the dielectric spectra results points to complex dynamics of 4ABO5* molecules in isotropic, cholesteric, and crystalline phases. Two well-separated maxima on the imaginary part of dielectric permittivity and the third low frequency relaxation process, hidden in the conductivity region, were detected and described in cholesteric and crystalline phases. Temperature dependence of mean relaxation times characterizing flip-flop motions and rotation around long axes, observed in all phases, is of the Arrhenius type.

20.
Acta Physiol (Oxf) ; 210(2): 392-402, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24148194

RESUMO

AIM: Insulin resistance induced by growth hormone (GH) is linked to promotion of lipolysis by unknown mechanisms. We hypothesized that suppression of the activity of pyruvate dehydrogenase in the active form (PDHa) underlies GH-induced insulin resistance similar to what is observed during fasting. METHODS: Eight healthy male subjects were studied four times in a randomized, single-blinded parallel design: Control, GH, Fasting (36 h) and GH + Fasting. GH (30 ng × kg(-1) × min(-1)) or saline was infused throughout the metabolic study day. Substrate metabolism and insulin sensitivity were assessed by indirect calorimetry and isotopically determined rates of glucose turnover before and after a hyperinsulinemic euglycemic clamp. PDHa activity, PDH-E1α phosphorylation, PDK4 expression and activation of insulin signalling proteins were assessed in skeletal muscle. RESULTS: Both fasting and GH promoted lipolysis, which was associated with ≈50% reduction in insulin sensitivity compared with the control day. PDHa activity was significantly reduced by GH as well as fasting. This was associated with increased inhibitory PDH-E1α phosphorylation on site 1 (Ser(293)) and 2 (Ser(300)) and up-regulation of PDK4 mRNA, while canonical insulin signalling to glucose transport was unaffected. CONCLUSION: Competition between intermediates of glucose and fatty acids seems to play a causal role in insulin resistance induced by GH in human subjects.


Assuntos
Hormônio do Crescimento Humano/farmacologia , Resistência à Insulina/fisiologia , Lipólise/fisiologia , Piruvato Desidrogenase (Lipoamida)/metabolismo , Western Blotting , Estudos Cross-Over , Técnica Clamp de Glucose , Humanos , Lipólise/efeitos dos fármacos , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/enzimologia , Músculo Esquelético/fisiopatologia , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
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