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1.
BMJ Open ; 13(3): e069654, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36918234

RESUMO

BACKGROUND: Diet plays a pivotal role in the onset and progression of Crohn's disease (CD). Nutritional interventions revealed effects on intestinal inflammation and gut microbial composition. However, data from well-designed and controlled dietary trials are lacking. Therefore, evidence-based dietary recommendations are still unavailable to patients and physicians. Here, we aim to investigate the effects of an evidence-based anti-inflammatory diet, and an ileocolonic-targeted capsule containing vitamin B2, B3 and C (ColoVit) on patients with CD and their healthy household members. METHODS AND ANALYSIS: In this multicentre, randomised, placebo-controlled, partially blinded nutritional intervention trial, we aim to recruit 255 CD patients with Harvey-Bradshaw Index <8 and a faecal calprotectin (FCal) cut-off of ≥100 µg/g at baseline. Participants will be randomised into two experimental intervention groups and one placebo group. In the experimental groups, participants will either adhere to the Groningen anti-inflammatory diet (GrAID) or ingest an ileocolonic-delivered oral vitamin B2/B3/C capsule (ColoVit). The study consists of a 12-week controlled interventional phase, which proceeds to a 9-month observational follow-up phase in which patients allocated to the GrAID group will be requested to continue the intervention on their own accord. Household members of participating patients will be asked to participate in the trial as healthy subjects and are allocated to the same group as their peer. The primary study outcome for patients is the change in FCal level from baseline. The primary outcome for household members is the change in gut microbial composition, which is set as secondary outcome for patients. ETHICS AND DISSEMINATION: The protocol has been approved by the Institutional Review Board of the Stichting Beoordeling Ethiek Biomedisch Onderzoek in Assen, the Netherlands. Written informed consent will be obtained from all participants. Results will be disseminated through peer-reviewed journals and conference presentations. TRIAL REGISTRATION NUMBER: NCT04913467.


Assuntos
Doença de Crohn , Microbiota , Humanos , Doença de Crohn/tratamento farmacológico , Dieta , Anti-Inflamatórios , Vitaminas , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
2.
Science ; 164(3886): 1408-10, 1969 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-5814684

RESUMO

Exoribonuclease purified from Ehrlich ascites tumor cell nuclei and in intact HeLa cell nuclei is irreversibly inactivated by tow concentrations of p-bromo- and p-iodoacetamidophenyl nucleotides and by thymidine-3'-fluorophosphate. Iodoacetate, bromoacetate, and thymidine-5'-fluorophosphate do not affect the enzyme. Although p-haloacetamidophenyl nucleotides inactivate ribonucleic acid polymerase of isolated HeLa cell nuclei, thymidine-3'-fluorophosphate does not affect the activity of this enzyme in vitro.


Assuntos
Carcinoma de Ehrlich/enzimologia , Núcleo Celular/enzimologia , Halogênios/farmacologia , Células HeLa/enzimologia , Nucleotídeos/farmacologia , Ribonucleases/antagonistas & inibidores , Animais , Iodoacetatos/farmacologia , RNA Nucleotidiltransferases/antagonistas & inibidores
3.
J Pharm Sci ; 87(12): 1496-501, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10189255

RESUMO

The X-ray crystal structures of four butyrophenone analogues have been completed and are reported herein. These include spiperone hydrochloride (I), N-methylspiperone hydrochloride (II), pimozide (III), and fluspirilene (IV). These structures were compared to other structurally similar molecules with similar pharmacological activity. In addition, a molecular modeling study was done in order to determine the low energy conformations of these molecules. It was found that calculations of parameters that describe the molecular conformations showed that all four molecules were structurally similar. Crystallographic data: [see text]


Assuntos
Cristalografia/métodos , Fluspirileno/química , Modelos Moleculares , Pimozida/química , Espiperona/análogos & derivados , Butirofenonas/química , Estrutura Molecular , Espiperona/química
4.
J Reprod Med ; 39(10): 838-40, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7837136

RESUMO

A 28-year-old woman developed hirsutism, facial edema and clitoromegaly after self-injection of long-acting synthetic androgens. The symptoms were ameliorated by administration of flutamide with a combination oral contraceptive. Flutamide appears to be useful in preventing sequelae of acute androgen excess in women and may be a rational therapy for chronic treatment of androgen excess in women.


Assuntos
Clitóris/efeitos dos fármacos , Flutamida/uso terapêutico , Hirsutismo/induzido quimicamente , Transtornos Paranoides/induzido quimicamente , Congêneres da Testosterona/efeitos adversos , Adulto , Edema/induzido quimicamente , Edema/tratamento farmacológico , Feminino , Flutamida/administração & dosagem , Flutamida/farmacologia , Hirsutismo/tratamento farmacológico , Humanos , Hipertrofia/induzido quimicamente , Hipertrofia/tratamento farmacológico , Transtornos Paranoides/tratamento farmacológico
5.
J Contam Hydrol ; 52(1-4): 3-27, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11695745

RESUMO

The input variables for a numerical model of reactive solute transport in groundwater include both transport parameters, such as hydraulic conductivity and infiltration, and reaction parameters that describe the important chemical and biological processes in the system. These parameters are subject to uncertainty due to measurement error and due to the spatial variability of properties in the subsurface environment. This paper compares the relative effects of uncertainty in the transport and reaction parameters on the results of a solute transport model. This question is addressed by comparing the magnitudes of the local sensitivity coefficients for transport and reaction parameters. General sensitivity equations are presented for transport parameters, reaction parameters, and the initial (background) concentrations in the problem domain. Parameter sensitivity coefficients are then calculated for an example problem in which uranium(VI) hydrolysis species are transported through a two-dimensional domain with a spatially variable pattern of surface complexation sites. In this example, the reaction model includes equilibrium speciation reactions and mass transfer-limited non-electrostatic surface complexation reactions. The set of parameters to which the model is most sensitive includes the initial concentration of one of the surface sites, the formation constant (Kf) of one of the surface complexes and the hydraulic conductivity within the reactive zone. For this example problem, the sensitivity analysis demonstrates that transport and reaction parameters are equally important in terms of how their variability affects the model results.


Assuntos
Modelos Teóricos , Poluentes do Solo/análise , Poluentes da Água/análise , Absorção , Adsorção , Sensibilidade e Especificidade , Movimentos da Água
6.
Br Dent J ; 217(9): 499-500, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25377816

RESUMO

The recent and widespread media interest highlighting the concerning number of children with poor oral health has, at last, put paediatric dentistry well and truly under the spotlight. Whether on the front page of the Sunday Times (http://www.thesundaytimes.co.uk/sto/news/uk_news/Health/Sugar/article1433860.ece), on GDPUK forums or live Twitter feeds as ITV's The Dentists was broadcast, the whole nation has suddenly awoken to the realisation that tens of thousands of children are undergoing multiple dental extractions under general anaesthesia in the UK every year. This is of course, not a new phenomenon, so why the sudden interest?


Assuntos
Cárie Dentária , Humanos , Reino Unido
7.
SAR QSAR Environ Res ; 22(7-8): 681-97, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22004550

RESUMO

Quantitative structure-activity relationship (QSAR) studies were conducted on an in-house database of cytochrome P450 enzyme 1A2 inhibitors using the comparative molecular field analysis (CoMFA), comparative molecular similarity analysis (CoMSIA) and hologram QSAR (HQSAR) approaches. The database consisted of 36 active molecules featuring varied core structures. The model based on the naphthalene substructure alignment incorporating 19 molecules yielded the best model with a CoMFA cross validation value q(2) of 0.667 and a Pearson correlation coefficient r(2) of 0.976; a CoMSIA q(2) value of 0.616 and r(2) value of 0.985; and a HQSAR q(2) value of 0.652 and r(2) value of 0.917. A second model incorporating 34 molecules aligned using the benzene substructure yielded an acceptable CoMFA model with q(2) value of 0.5 and r(2) value of 0.991. Depending on the core structure of the molecule under consideration, new CYP1A2 inhibitors will be designed based on the results from these models.


Assuntos
Inibidores do Citocromo P-450 CYP1A2 , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Relação Quantitativa Estrutura-Atividade , Modelos Teóricos
15.
Macromolecules ; 8(4): 531-5, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1177499

RESUMO

The relaxation behavior of the helix-coil transition has been investigated for all sizes of polypeptides. Unlike previously reported results, regardless of the size of polypeptides, the first-order kinetics plays a principal role in the relaxation process when a helical state is relaxed to a half-coiled state [i.e. s(f) is congruent to 1, where s(f) is the helix stability parameter at the final state]. On the other hand, when a helical state is relaxed to a coiled state [i.e., s(f) is less than 1], the zeroth-order kinetics plays a major role. In addition, the range of the validity of a kinetic version of the zipper model has been investigated. We have found that when a helical state is relaxed to a state where s(f) is less than or equal to 1, the zipper model is valid for polypeptides with chain length N satisfying the relation N is less than 1/(sigmagammaC)1/2 where sigma is the cooperativity parameter and gammaC is the coil nucleation rate parameter.


Assuntos
Peptídeos , Conformação Proteica , Cinética , Matemática , Peso Molecular , Probabilidade
16.
Biochemistry ; 16(26): 5819-24, 1977 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-22344

RESUMO

The lowest stages of polymerization of tobacco mosaic virus protein were studied by means of high-speed sedimentation equilibrium experiments. Several distinct modes of polymerization were found. At pH 7.1 the expected monomer-trimer-higher polymer equilibrium was observed--very little dimer was detected at this pH. At pH 7.5, however, a strong dimerization was observed--neither monomer nor trimer was detected at this pH. An octamer appeared to be the only species present other than the dimer. When 0.01 M beta-mercaptoethanol was added to the solvent pH 7.5, the dimer was dissociated, resulting in a monomer-trimer association. The dimerization may be the basis for the larger "doubled" polymers formed by the protein at alkaline pH, while the octamer may correspond to the 8S peak frequently observed in sedimentation velocity experiments at alkaline pH. On the other hand, the monomer-trimer-higher polymer equilibrium may correspond to the single helix formed by the protein at slightly acid pH and to the combination of 4S and 20S peaks seen in sedimentation velocity experiments at slightly acid pH.


Assuntos
Vírus do Mosaico do Tabaco/análise , Proteínas Virais , Concentração de Íons de Hidrogênio , Substâncias Macromoleculares , Matemática , Peso Molecular
17.
J Bacteriol ; 124(1): 247-51, 1975 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-809415

RESUMO

A uracil-requiring auxotroph of Anacystis nidulans was isolated after treatment with N-methyl-N'-nitrosoguanidine. Neither precursors in the de novo pyrimidine pathway nor compounds of "salvage" or degradative pathways could replace the uracil requirement. The reversion frequency for mutation to a nonuracil requirement for growth was 2.0 times 10(-8). The calculated average rate of uracil utilization was 1.1 times 10(-17) mol of uracil per unit cell mass/h. The amount of uracil required for the synthesis of a unit cell mass was 3.8 times 10(-17) mol of uracil.


Assuntos
Cianobactérias/metabolismo , Mutação , Uracila/metabolismo , Cianobactérias/crescimento & desenvolvimento , Cianobactérias/isolamento & purificação , Metilnitronitrosoguanidina , Mutagênicos
18.
Biochemistry ; 16(17): 3727-39, 1977 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-20126

RESUMO

By assuming that the opening of hydrogen bonds due to thermal fluctuations is a very fast step and that the reaction of formaldehyde with the imino or amino group is a slow step, we have constructed a model for the unwinding process of poly(A-U) induced by formaldehyde. The denaturation equation derived from the model is essentially the same as that of the zipper model for moderately long chain lengths. The model predicts the following phenomena which are in agreement with our experimental findings. The rate of unwinding is approximately first order for unfractionated polynucleotides and zero order for fractionated samples. This means that formaldehyde ruptures helical residues sequentially starting from the ends and working toward the center. Our model further predicts that the denaturation rate is linearly dependent on -log[Na+] and pH at low ionic strength and is almost independent of [Na+] and pH at high ionic strength. Spectrophotometric measurements on poly(A-U) were done to confirm our theoretical findings.


Assuntos
Formaldeído , Poli A , Poli U , Fenômenos Químicos , Química , Concentração de Íons de Hidrogênio , Cinética , Matemática , Peso Molecular , Desnaturação de Ácido Nucleico , Concentração Osmolar , Cloreto de Sódio
19.
J Bacteriol ; 135(1): 286-8, 1978 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-97274

RESUMO

When levulinic acid, a competitive inhibitor of delta-aminolevulinic acid dehydratase, was added to growing cultures of blue-green algae (cyanobacteria), delta-aminolevulinic acid was excreted into the medium and cell growth was inhibited.


Assuntos
Ácido Aminolevulínico/biossíntese , Cianobactérias/metabolismo , Ácidos Levulínicos/biossíntese , Cianobactérias/enzimologia , Ácidos Levulínicos/metabolismo , Ácidos Levulínicos/farmacologia , Sintase do Porfobilinogênio/antagonistas & inibidores
20.
Plant Physiol ; 56(1): 126-9, 1975 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16659241

RESUMO

Oxygen isotope fractionation ((18)O/(16)O) at the natural abundance level has been measured during photosynthesis of a blue-green and a green alga. When sufficient attention is paid to removal of contaminating air O(2) before and during the experiments, then the photosynthetic O(2) evolved, as compared to the water O(2), had an average difference of -0.36% for a blue-green alga and -0.80% for a green alga. These experiments suggest that there is no reason to invoke an inverse isotope effect in photosynthesis as part of the explanation for the (18)O enrichment in atmospheric O(2) relative to O(2) in oceanic waters. In addition, in an indirect way, the experiments also support the argument that the bulk of O(2) evolved during photosynthesis comes from water. A 10% contribution of O(2) arising from CO(2) would have been detectable in the present work.

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