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1.
Clin Transplant ; 36(10): e14643, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35262975

RESUMO

BACKGROUND: Liver transplant centers vary in approach to intraoperative vascular accesses, monitoring of cardiac function and temperature management. Evidence is limited regarding impact of selected modalities on postoperative outcomes. OBJECTIVES: To review the literature and provide expert panel recommendations on optimal intraoperative arterial blood pressure (BP), central venous pressure (CVP), and vascular accesses, monitoring of cardiac function and intraoperative temperature management regarding immediate and short-term outcomes after orthotopic liver transplant (OLT). METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. Recommendations made for: (1) Vascular accesses, arterial BP and CVP monitoring, (2) cardiac function monitoring, and (3) Intraoperative temperature management (CRD42021239908). RESULTS: Of 2619 articles screened 16 were included. Studies were small, retrospective, and observational. Vascular access studies demonstrated low rates of insertion complications. TEE studies demonstrated low rates of esophageal hemorrhage. One study found lower hospital-LOS and 30-day mortality in patients monitored with both PAC and TEE. Other monitoring studies were heterogenous in design and outcomes. Temperature studies showed increased blood transfusion and ventilation times in hypothermic groups. CONCLUSIONS: Recommendations were made for; routine arterial and CVP monitoring as a minimum standard of practice, consideration of discrepancy between peripheral and central arterial BP in patients with hemodynamic instability and high vasopressor requirements, and routine use of high flow cannulae while monitoring for extravasation and hematoma formation. Availability and expertise in PAC and/or TEE monitoring is strongly recommended particularly in hemodynamic instability, portopulmonary HT and/or cardiac dysfunction. TEE use is recommended as an acceptable risk in patients with treated esophageal varices and is an effective diagnostic tool for emergency cardiovascular collapse. Maintenance of intraoperative normothermia is strongly recommended.


Assuntos
Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Monitorização Intraoperatória , Pressão Venosa Central , Vasoconstritores
2.
Semin Cell Dev Biol ; 88: 107-118, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29432955

RESUMO

Plant defensins are an extensive family of small cysteine rich proteins characterised by a conserved cysteine stabilised alpha beta protein fold which resembles the structure of insect and vertebrate defensins. However, secondary structure and disulphide topology indicates two independent superfamilies of defensins with similar structures that have arisen via an extreme case of convergent evolution. Defensins from plants and insects belong to the cis-defensin superfamily whereas mammalian defensins belong to the trans-defensin superfamily. Plant defensins are produced by all species of plants and although the structure is highly conserved, the amino acid sequences are highly variable with the exception of the cysteine residues that form the stabilising disulphide bonds and a few other conserved residues. The majority of plant defensins are components of the plant innate immune system but others have evolved additional functions ranging from roles in sexual reproduction and development to metal tolerance. This review focuses on the antifungal mechanisms of plant defensins. The activity of plant defensins is not limited to plant pathogens and many of the described mechanisms have been elucidated using yeast models. These mechanisms are more complex than simple membrane permeabilisation induced by many small antimicrobial peptides. Common themes that run through the characterised mechanisms are interactions with specific lipids, production of reactive oxygen species and induction of cell wall stress. Links between sequence motifs and functions are highlighted where appropriate. The complexity of the interactions between plant defensins and fungi helps explain why this protein superfamily is ubiquitous in plant innate immunity.


Assuntos
Defensinas/imunologia , Fungos/efeitos dos fármacos , Doenças das Plantas/imunologia , Imunidade Vegetal/genética , Proteínas de Plantas/imunologia , Plantas/imunologia , Parede Celular/química , Parede Celular/efeitos dos fármacos , Sequência Conservada , Defensinas/genética , Defensinas/farmacologia , Resistência à Doença/genética , Evolução Molecular , Fungos/química , Fungos/metabolismo , Regulação da Expressão Gênica de Plantas/imunologia , Interações Hospedeiro-Patógeno , Lipídeos/química , Lipídeos/imunologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/farmacologia , Plantas/genética , Plantas/microbiologia , Dobramento de Proteína , Estrutura Secundária de Proteína , Espécies Reativas de Oxigênio/imunologia , Espécies Reativas de Oxigênio/metabolismo
3.
Cell Mol Life Sci ; 74(4): 663-682, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27557668

RESUMO

Defensins are a well-characterised group of small, disulphide-rich, cationic peptides that are produced by essentially all eukaryotes and are highly diverse in their sequences and structures. Most display broad range antimicrobial activity at low micromolar concentrations, whereas others have other diverse roles, including cell signalling (e.g. immune cell recruitment, self/non-self-recognition), ion channel perturbation, toxic functions, and enzyme inhibition. The defensins consist of two superfamilies, each derived from an independent evolutionary origin, which have subsequently undergone extensive divergent evolution in their sequence, structure and function. Referred to as the cis- and trans-defensin superfamilies, they are classified based on their secondary structure orientation, cysteine motifs and disulphide bond connectivities, tertiary structure similarities and precursor gene sequence. The utility of displaying loops on a stable, compact, disulphide-rich core has been exploited by evolution on multiple occasions. The defensin superfamilies represent a case where the ensuing convergent evolution of sequence, structure and function has been particularly extreme. Here, we discuss the extent, causes and significance of these convergent features, drawing examples from across the eukaryotes.


Assuntos
Defensinas/genética , Defensinas/metabolismo , Filogenia , Sequência de Aminoácidos , Animais , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Defensinas/química , Evolução Molecular , Dosagem de Genes , Humanos , Modelos Moleculares , Conformação Proteica , Alinhamento de Sequência
4.
Biochim Biophys Acta ; 1858(6): 1099-109, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26896695

RESUMO

Plant defensins interact with phospholipids in bilayers as part of their cytotoxic activity. Solanaceous class II defensins with the loop 5 sequence pattern "S-[KR]-[ILVQ]-[ILVQ]-[KR]-[KR]" interact with PI(4,5)P2. Here, the prototypical defensin of this class, NaD1, is used to characterise the biophysical interactions between these defensins and phospholipid bilayers. Binding of NaD1 to bilayers containing PI(4,5)P2 occurs rapidly and the interaction is very strong. Dual polarisation interferometry revealed that NaD1 does not dissociate from bilayers containing PI(4,5)P2. Binding of NaD1 to bilayers with or without PI(4,5)P2 induced disorder in the bilayer. However, permeabilisation assays revealed that NaD1 only permeabilised liposomes with PI(4,5)P2 in the bilayer, suggesting a role for this protein-lipid interaction in the plasma membrane permeabilising activity of this defensin. No defensins in the available databases have the PI(4,5)P2 binding sequence outside the solanaceous class II defensins, leading to the hypothesis that PI(4,5)P2 binding co-evolved with the C-terminal propeptide to protect the host cell against the effects of the tight binding of these defensins to their cognate lipid as they travel along the secretory pathway. This data has allowed us to develop a new model to explain how this class of defensins permeabilises plasma membranes to kill target cells.


Assuntos
Proteínas de Arabidopsis/fisiologia , Lipídeos de Membrana/metabolismo , NADH Desidrogenase/fisiologia , Fosfatidilinositol 4,5-Difosfato/metabolismo , Sequência de Aminoácidos , Proteínas de Arabidopsis/química , Bicamadas Lipídicas , Dados de Sequência Molecular , NADH Desidrogenase/química , Ligação Proteica , Homologia de Sequência de Aminoácidos
5.
Mol Biol Evol ; 33(9): 2345-56, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27297472

RESUMO

The defensin and defensin-like proteins are an extensive group of small, cationic, disulfide-rich proteins found in animals, plants, and fungi and mostly perform roles in host defense. The term defensin was originally used for small mammalian proteins found in neutrophils and was subsequently applied to insect proteins and plant γ-thionins based on their perceived sequence and structural similarity. Defensins are often described as ancient innate immunity molecules and classified as a single superfamily and both sequence alignments and phylogenies have been constructed. Here, we present evidence that the defensins have not all evolved from a single ancestor. Instead, they consist of two analogous superfamilies, and extensive convergent evolution is the source of their similarities. Evidence of common origin necessarily gets weaker for distantly related genes, as is the case for defensins, which are both divergent and small. We show that similarities that have been used as evidence for common origin are all expected by chance in short, constrained, disulfide-rich proteins. Differences in tertiary structure, secondary structure order, and disulfide bond connectivity indicate convergence as the likely source of the similarity. We refer to the two evolutionarily independent groups as the cis-defensins and trans-defensins based on the orientation of the most conserved pair of disulfides.


Assuntos
Defensinas/química , Defensinas/genética , Sequência de Aminoácidos , Animais , Evolução Biológica , Defensinas/metabolismo , Drosophila melanogaster , Evolução Molecular , Humanos , Modelos Moleculares , Filogenia , Estrutura Secundária de Proteína , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade
6.
Antimicrob Agents Chemother ; 60(10): 6302-12, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27503651

RESUMO

The plant defensin NaD1 is a potent antifungal molecule that also targets tumor cells with a high efficiency. We examined the features of NaD1 that contribute to these two activities by producing a series of chimeras with NaD2, a defensin that has relatively poor activity against fungi and no activity against tumor cells. All plant defensins have a common tertiary structure known as a cysteine-stabilized α-ß motif which consists of an α helix and a triple-stranded ß-sheet stabilized by four disulfide bonds. The chimeras were produced by replacing loops 1 to 7, the sequences between each of the conserved cysteine residues on NaD1, with the corresponding loops from NaD2. The loop 5 swap replaced the sequence motif (SKILRR) that mediates tight binding with phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] and is essential for the potent cytotoxic effect of NaD1 on tumor cells. Consistent with previous reports, there was a strong correlation between PI(4,5)P2 binding and the tumor cell killing activity of all of the chimeras. However, this correlation did not extend to antifungal activity. Some of the loop swap chimeras were efficient antifungal molecules, even though they bound poorly to PI(4,5)P2, suggesting that additional mechanisms operate against fungal cells. Unexpectedly, the loop 1B swap chimera was 10 times more active than NaD1 against filamentous fungi. This led to the conclusion that defensin loops have evolved as modular components that combine to make antifungal molecules with variable mechanisms of action and that artificial combinations of loops can increase antifungal activity compared to that of the natural variants.


Assuntos
Antifúngicos/farmacologia , Defensinas/química , Defensinas/farmacologia , Nicotiana/química , Antifúngicos/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Defensinas/genética , Defensinas/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Fusarium/efeitos dos fármacos , Humanos , Lipossomos , Neomicina/farmacologia , Permeabilidade , Fosfatidilinositol 4,5-Difosfato/metabolismo , Dobramento de Proteína , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo
7.
Nat Chem Biol ; 10(11): 950-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25282505

RESUMO

Severe forms of pneumococcal meningitis, bacteraemia and pneumonia result in more than 1 million deaths each year despite the widespread introduction of carbohydrate-protein conjugate vaccines against Streptococcus pneumoniae. Here we describe a new and highly efficient antipneumococcal vaccine design based on synthetic conjugation of S. pneumoniae capsule polysaccharides to the potent lipid antigen α-galactosylceramide, which stimulates invariant natural killer T (iNKT) cells when presented by the nonpolymorphic antigen-presenting molecule CD1d. Mice injected with the new lipid-carbohydrate conjugate vaccine produced high-affinity IgG antibodies specific for pneumococcal polysaccharides. Vaccination stimulated germinal center formation; accumulation of iNKT cells with a T follicular helper cell phenotype; and increased frequency of carbohydrate-specific, long-lived memory B cells and plasmablasts. This new lipid-carbohydrate vaccination strategy induced potent antipolysaccharide immunity that protected against pneumococcal disease in mice and may also prove effective for the design of carbohydrate-based vaccines against other major bacterial pathogens.


Assuntos
Carboidratos/química , Lipídeos/química , Vacinas Pneumocócicas/síntese química , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Vacinas Sintéticas/química , Vacinas Sintéticas/imunologia , Animais , Anticorpos Monoclonais/imunologia , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Antígenos CD1d/imunologia , Antígenos CD1d/metabolismo , Linfócitos B/citologia , Linfócitos B/imunologia , Carboidratos/administração & dosagem , Linhagem Celular , Centro Germinativo/citologia , Centro Germinativo/imunologia , Células HL-60 , Humanos , Imunização Passiva , Memória Imunológica/imunologia , Cinética , Lipídeos/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células T Matadoras Naturais/imunologia , Vacinas Pneumocócicas/administração & dosagem , Vacinas Pneumocócicas/química , Fatores de Tempo , Vacinas Sintéticas/administração & dosagem
8.
Ther Drug Monit ; 37(1): 58-65, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24887633

RESUMO

BACKGROUND: Mitotane is the drug of choice in medical treatment of adrenocortical carcinoma. The antineoplastic effect seems to be correlated with a minimum plasma level of 14 mg/L, but plasma concentration build-up is in general slow due to the long elimination half-life. Consequently, the therapeutic effect sets in after weeks or even months. The objective of this study was to develop a pharmacokinetic model that enables clinicians to adjust dosing based on a target drug exposure, which facilitates personalized therapy. METHODS: Data on dosing and plasma level measurements performed throughout mitotane therapy were retrospectively collected in a population of 29 patients from 2 hospitals. A population pharmacokinetic model was constructed based on data from 20 patients using iterative 2-stage Bayesian fitting (MWPharm). The model was validated in an independent sample of 9 patients. RESULTS: The concentration-time data were best described by a 3-compartment model. The model estimated mitotane clearance at 0.94 ± 0.37 L/h and a volume of distribution in the steady state at 161 ± 68 L/kg of lean body mass. The mean prediction error was 14% ± 13%. CONCLUSIONS: A pharmacokinetic model was developed, which characterized mitotane by slow clearance and large volume of distribution. The model seems to be able to predict mitotane levels in individual patients with an error margin of 14%. The model enables one to adapt dosing based on individual plasma level measurements in prospective setting, which improves the accuracy of the prediction. We expect that individualization of mitotane dosing leads to anticipated and more rapid attainment of the therapeutic levels and potentially to improved clinical management of mitotane treatment.


Assuntos
Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Neoplasias do Córtex Suprarrenal/metabolismo , Carcinoma Adrenocortical/tratamento farmacológico , Carcinoma Adrenocortical/metabolismo , Antineoplásicos Hormonais/farmacocinética , Antineoplásicos Hormonais/uso terapêutico , Mitotano/farmacocinética , Mitotano/uso terapêutico , Adulto , Idoso , Antineoplásicos Hormonais/administração & dosagem , Área Sob a Curva , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitotano/administração & dosagem , Modelos Estatísticos , Medicina de Precisão , Estudos Retrospectivos , Adulto Jovem
9.
Phys Rev Lett ; 113(13): 138701, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25302922

RESUMO

We introduce a simple class of distribution networks that withstand damage by being repairable instead of redundant. Instead of asking how hard it is to disconnect nodes through damage, we ask how easy it is to reconnect nodes after damage. We prove that optimal networks on regular lattices have an expected cost of reconnection proportional to the lattice length, and that such networks have exactly three levels of structural hierarchy. We extend our results to networks subject to repeated attacks, in which the repairs themselves must be repairable. We find that, in exchange for a modest increase in repair cost, such networks are able to withstand any number of attacks.

10.
Soft Matter ; 10(31): 5656-61, 2014 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-24995505

RESUMO

The final structure and properties of synthetic peptides mainly depend on their sequence composition and experimental conditions. This work demonstrates that a variation in the positions of hydrophobic residues within a peptide sequence can tune the self-assembly. Techniques employed are atomic force microscopy, transmission electron microscopy and an innovative method based on surface acoustic waves. In addition, a systematic investigation on pH dependence was carried out by utilizing constant experimental parameters.


Assuntos
Aminoácidos/química , Interações Hidrofóbicas e Hidrofílicas , Peptídeos/química , Estrutura Secundária de Proteína , Sequência de Aminoácidos , Dicroísmo Circular , Concentração de Íons de Hidrogênio , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Modelos Moleculares , Dados de Sequência Molecular
11.
Deep Sea Res 2 Top Stud Oceanogr ; 103: 238-263, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26028824

RESUMO

We report here the results of ten oceanographic survey cruises carried out in the Gulf of Maine - Georges Bank region of the Northwest Atlantic during the late spring to summer period in 2007, 2008 and 2010, for which we examine and characterize relationships among dissolved inorganic nutrient fields, water mass dynamics and cell densities of the toxic dinoflagellate Alexandrium fundyense. Nutrients are supplied to continental shelf waters of the Gulf of Maine - Georges Bank region by inflows of deep offshore water masses; once in the Gulf they are transported with the residual circulation and mix with surface waters, both in the Gulf and on the Bank. Those fluxes of offshore water masses and their nutrient loads are the major source of nutrients for phytoplankton production in the region, including annual blooms of A. fundyense in the Gulf and on Georges Bank. This much is already known. We suggest here that the locations and magnitude of A. fundyense blooms are controlled in part by variable nutrient fluxes to the interior Gulf of Maine from offshore, and, those interior Gulf of Maine waters are, in turn, the main nutrient source to Georges Bank, which are brought onto the Bank by tidal pumping on the Northern Flank. We present evidence that nitrate is the initial form of nitrogenous nutrient for A. fundyense blooms, but it is quickly depleted to limiting concentrations of less than 0.5 µM, at which time continued growth and maintenance of the population is likely fueled by recycled ammonium. We also show that phosphate may be the limiting nutrient over much of Georges Bank in summer, allowing recycled ammonium concentrations to increase. Our temperature-salinity analyses reveal spatial and temporal (seasonal and interannual) variability in the relative proportions of two deep source waters that enter the Gulf of Maine at depth through the Northeast Channel: Warm Slope Water (WSW) and Labrador Slope Water (LSW). Those two source waters are known to vary in their nutrient loads, with nitrate concentrations about 50% higher in WSW than LSW, for example, and as such the proportions of these two water masses to one another are important determinants of the overall nutrient loads in the interior Gulf. In addition to these deep slope water fluxes, we show evidence here of episodic fluxes of relatively fresh and low-nutrient shelf waters from the Nova Scotian Shelf, which enter the Gulf in pulses at depths between the surface and approximately 150 m, displacing deep slope waters, and consequently they significantly dilute the Gulf's interior waters, reducing nutrient concentrations and, in turn, affect the magnitude of A. fundyense blooms.

12.
Deep Sea Res 2 Top Stud Oceanogr ; 103: 163-173, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24976691

RESUMO

A series of oceanographic surveys on Georges Bank document variability of populations of the toxic dinoflagellate Alexandrium fundyense on time scales ranging from synoptic to seasonal to interannual. Blooms of A. fundyense on Georges Bank can reach concentrations on the order of 104 cells l-1, and are generally bank-wide in extent. Georges Bank populations of A. fundyense appear to be quasi-independent of those in the adjacent coastal Gulf of Maine, insofar as they occupy a hydrographic niche that is colder and saltier than their coastal counterparts. In contrast to coastal populations that rely on abundant resting cysts for bloom initiation, very few cysts are present in the sediments on Georges Bank. Bloom dynamics must therefore be largely controlled by the balance between growth and mortality processes, which are at present largely unknown for this population. Based on correlations between cell abundance and nutrient distributions, ammonium appears to be an important source of nitrogen for A. fundyense blooms on Georges Bank.

13.
NPJ Digit Med ; 7(1): 66, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472270

RESUMO

Mobile Health (mHealth) has the potential to be transformative in the management of chronic conditions. Machine learning can leverage self-reported data collected with apps to predict periods of increased health risk, alert users, and signpost interventions. Despite this, mHealth must balance the treatment burden of frequent self-reporting and predictive performance and safety. Here we report how user engagement with a widely used and clinically validated mHealth app, myCOPD (designed for the self-management of Chronic Obstructive Pulmonary Disease), directly impacts the performance of a machine learning model predicting an acute worsening of condition (i.e., exacerbations). We classify how users typically engage with myCOPD, finding that 60.3% of users engage frequently, however, less frequent users can show transitional engagement (18.4%), becoming more engaged immediately ( < 21 days) before exacerbating. Machine learning performed better for users who engaged the most, however, this performance decrease can be mostly offset for less frequent users who engage more near exacerbation. We conduct interviews and focus groups with myCOPD users, highlighting digital diaries and disease acuity as key factors for engagement. Users of mHealth can feel overburdened when self-reporting data necessary for predictive modelling and confidence of recognising exacerbations is a significant barrier to accurate self-reported data. We demonstrate that users of mHealth should be encouraged to engage when they notice changes to their condition (rather than clinically defined symptoms) to achieve data that is still predictive for machine learning, while reducing the likelihood of disengagement through desensitisation.

14.
Artigo em Inglês | MEDLINE | ID: mdl-36936396

RESUMO

Introduction: Van der Woude Syndrome (VWS) is an autosomal dominant disorder responsible for 2% of all syndromic orofacial clefts (OFCs) with IRF6 being the primary causal gene (70%). Cases may present with lip pits and either cleft lip, cleft lip with cleft palate, or cleft palate, with marked phenotypic discordance even among individuals carrying the same mutation. This suggests that genetic or epigenetic modifiers may play additional roles in the syndrome's etiology and variability in expression. We report the first DNA methylation profiling of 2 pairs of monozygotic twins with VWS. Our goal is to explore epigenetic contributions to VWS etiology and variable phenotypic expressivity by comparing DNAm profiles in both twin pairs. While the mutations that cause VWS in these twins are known, the additional mechanism behind their phenotypic risk and variability in expression remains unclear. Methods: We generated whole genome DNAm data for both twin pairs. Differentially methylated positions (DMPs) were selected based on: (1) a coefficient of variation in DNAm levels in unaffected individuals < 20%, and (2) intra-twin pair absolute difference in DNAm levels >5% (delta beta > | 0.05|). We then divided the DMPs in two subgroups for each twin pair for further analysis: (1) higher methylation levels in twin A (Twin A > Twin B); and (2) higher methylation levels in twin B (Twin B >Twin A). Results and Discussion: Gene ontology analysis revealed a list of enriched genes that showed significant differential DNAm, including clef-associated genes. Among the cleft-associated genes, TP63 was the most significant hit (p=7.82E-12). Both twin pairs presented differential DNAm levels in CpG sites in/near TP63 (Twin 1A > Twin 1B and Twin 2A < Twin 2B). The genes TP63 and IRF6 function in a biological regulatory loop to coordinate epithelial proliferation and differentiation in a process that is critical for palatal fusion. The effects of the causal mutations in IRF6 can be further impacted by epigenetic dysregulation of IRF6 itself, or genes in its pathway. Our data shows evidence that changes in DNAm is a plausible mechanism that can lead to markedly distinct phenotypes, even among individuals carrying the same mutation.

15.
Int J Chron Obstruct Pulmon Dis ; 18: 2335-2339, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37904748

RESUMO

Introduction: The GOLD (Global Initiative for Chronic Obstructive Lung Disease) 2023 guidelines proposed important changes to the stratification of disease severity using the "ABCD" assessment tool. The highest risk groups "C" and "D" were combined into a single category "E" based on exacerbation history, no longer considering symptomology. Purpose: We quantify the differential disease progression of individuals initially stratified by the GOLD 2022 "ABCD" scheme to evaluate these proposed changes. Patients and Methods: We utilise data collected from 1529 users of the myCOPD mobile app, a widely used and clinically validated app supporting people living with COPD in the UK. For patients in each GOLD group, we quantify symptoms using COPD Assessment Tests (CAT) and rate of exacerbation over a 12-month period post classification. Results: CAT scores for users initially classified into GOLD C and GOLD D remain significantly different after 12 months (Kolmogorov-Smirnov statistic = 0.59, P = 8.2 × 10-23). Users initially classified into GOLD C demonstrate a significantly lower exacerbation rate over the 12 months post classification than those initially in GOLD D (Kolmogorov-Smirnov statistic = 0.26; P = 3.1 × 10-2; all exacerbations). Further, those initially classified as GOLD B have higher CAT scores and exacerbation rates than GOLD C in the following 12 months. Conclusion: CAT scores remain important for stratifying disease progression both in-terms of symptomology and future exacerbation risk. Based on this evidence, the merger of GOLD C and GOLD D should be reconsidered.


Assuntos
Asma , Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Volume Expiratório Forçado , Índice de Gravidade de Doença , Progressão da Doença
16.
Diabetes Obes Metab ; 14(6): 555-64, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22268426

RESUMO

AIM: To test the antidiabetic efficacy of ibipinabant, this new cannabinoid receptor 1 (CB1) antagonist was compared with food-restriction-induced weight loss, rosiglitazone (4 mg/kg) and rimonabant (3 and 10 mg/kg), using parameters of glycaemic control in male Zucker diabetic fatty (ZDF) rats. METHODS: Body weight, food and water intake, fasted and non-fasted glucose and insulin, glucose tolerance and glycosylated haemoglobin (HbA1c) were all assessed over the course of the 9-week study. Pancreatic insulin content and islet area were also evaluated. RESULTS: At the end of the study, vehicle-treated ZDF rats were severely hyperglycaemic and showed signs of ß-cell decline, including dramatic reductions in unfasted insulin levels. Ibipinanbant (10 mg/kg) reduced the following relative to vehicle controls: fasting glucose (-61%), glucose excursion area under the curve (AUC) in an oral glucose tolerance test (OGTT, -44%) and HbA1c (-50%). Furthermore, non-fasting insulin, islet area and islet insulin content were all increased (71, 40 and 76%, respectively) relative to vehicle controls by the end of the study. All of these effects were similar to those of rimonabant and rosiglitazone, where ibipinabant was slightly more effective than rimonabant at the lowest dose and somewhat less effective than rosiglitazone at all doses. These antidiabetic effects appear independent of weight loss because none of the parameters above were consistently improved by the comparable weight loss induced by food restriction. CONCLUSIONS: Ibipinabant may have weight loss-independent antidiabetic effects and may have the potential to attenuate ß-cell loss in a model of progressive ß-cell dysfunction.


Assuntos
Amidinas/farmacologia , Hemoglobinas Glicadas/metabolismo , Hipoglicemiantes/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Insulina/metabolismo , Pirazóis/farmacologia , Redução de Peso/efeitos dos fármacos , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Restrição Calórica , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/efeitos dos fármacos , Imuno-Histoquímica , Insulina/sangue , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Masculino , Ratos , Ratos Zucker
17.
J Nanosci Nanotechnol ; 12(3): 2374-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22755061

RESUMO

Airbrushed multi-walled carbon nanotube (MWNT) networks were investigated as a new counter electrode for dye-sensitized TiO2 photoelectrochemical solar cells. The structural and physical properties of the MWNTs were studied by various techniques including SEM, TEM, Raman, optical absorption, and electrochemical impedance spectroscopy (EIS). The MWNTs exhibited catalytic activity for the reduction of triiodide in the electrolyte as studied by EIS measurements. The performance of the dye-sensitized solar cells was improved by using MWNTs as counter electrodes. This observation is explained by the significantly increased contact area between the MWNT counter electrode and the electrolyte which facilitates efficient charge transportation in the solar cell. We demonstrated that the MWNTs are suitable for replacing expensive Pt electrodes for fabricating high efficiency dye-sensitized solar cells. The process used in this study is also technically attractive for large scale and economic production.

18.
Pharmaceuticals (Basel) ; 15(8)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-36015083

RESUMO

Non-covalent π-π stacking interactions often play a key role in the stability of the secondary and tertiary structures of peptides and proteins, respectively, and can be a means of ensuring the binding of ligands within protein and enzyme binding sites. It is generally accepted that minor structural changes to the aromatic ring, such as substitution, can have a large influence on these interactions. Nevertheless, a thorough understanding of underpinning phenomena guiding these key interactions is still limited. This is especially true for larger aromatic structures. To expand upon this knowledge, elaborate ab initio calculations were performed to investigate the effect of halogenation on the stability of 3-methylindole stacking. 3-Methylindole served as a representation of the tryptophan side chain, and is a frequently used motif in drug design and development. Moreover, an expression is derived that is able to accurately predict the interaction stability of stacked halogenated 3-methylindole dimers as well as halogenated toluene dimers, based on monomer level calculated DFT descriptors. We aim for this expression to provide the field with a straightforward and reliable method to assess the effect of halogenation on the π-π stacking interactions between aromatic scaffolds.

19.
Eur J Cancer ; 172: 252-263, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35803176

RESUMO

BACKGROUND: Gastroenteropancreatic (GEP) neuroendocrine neoplasms (NENs) comprise a group of rare malignant tumours with heterogeneous behaviour. This study aimed to assess long-term survival and prognostic factors associated with survival, in order to optimise counselling. PATIENTS AND METHODS: This population-based study included all GEP-NENs diagnosed between 1989 and 2016 in the Netherlands, selected from the Netherlands Cancer Registry. Overall survival (OS) and relative survival (RS) were calculated. A Cox Proportional Hazard analysis was used to identify prognostic factors (gender, age, tumour stage, location and treatment) for OS. Analyses were stratified by metastatic disease status and tumour grade. RESULTS: In total, 9697 patients were included. In grade 1, 2 and 3 non-metastatic GEP-NENs (N = 6544), 5-year OS and RS were 81% and 88%, 78% and 83%, and 26% and 30%, respectively. In grade 1 non-metastatic GEP-NENs 10-year OS and RS were 68% and 83%. In grade 1, 2 and 3 metastatic GEP-NENs (N = 3153), 5-year OS and RS rates were 47% and 52%, 38% and 41%, and 5% and 5%, respectively. The highest (relative) survival rates were found in appendicular and rectal NENs, demonstrating 10-year OS and RS of 87% and 93%, and 81% and 95%, respectively. CONCLUSIONS: These long-term follow-up data demonstrate significant differences in survival for different grades, tumour stage, and primary origin of GEP-NENs, with the most favourable overall and RS rates in patients with non-metastatic grade 1 appendicular and rectal NENs. This study demonstrates unique long-term OS and RS rates using combined stratification by tumour site, grade and stage.


Assuntos
Neoplasias Intestinais , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Neoplasias Gástricas , Humanos , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/patologia , Prognóstico , Neoplasias Gástricas/patologia
20.
Cancers (Basel) ; 14(6)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35326518

RESUMO

We aimed to develop a disease-specific adrenocortical carcinoma (ACC) health-related quality of life (HRQoL) questionnaire (ACC-QOL) and assess HRQoL in a population-based cohort of patients with ACC. Development was in line with European Organization for Research and Treatment of Cancer (EORTC) guidelines, though not an EORTC product. In phase I and II, we identified 90 potential HRQoL issues using literature and focus groups, which were reduced to 39 by healthcare professionals. Pilot testing resulted in 28 questions, to be used alongside the EORTC QLQ-C30. In Phase III, 100 patients with ACC were asked to complete the questionnaires twice in the PROFILES registry (3-month interval, respondents: first 67, second 51). Confirmatory factor analysis demonstrated the structural validity of 26 questions with their scale structure (mitotane side-effects, hypercortisolism/hydrocortisone effects, emotional effects). Internal consistency and reliability were good (Cronbach's alpha 0.897, Interclass correlation coefficient 0.860). Responsiveness analysis showed good discriminative ability (AUC 0.788). Patients diagnosed more than 5 years ago reported a good HRQoL compared with the Dutch reference population, but experienced residual fatigue and emotional problems. Patients who underwent recent treatment reported a lower HRQoL and problems in several domains. In conclusion, we developed an ACC-specific HRQoL questionnaire with good psychometric properties.

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