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1.
Nat Commun ; 14(1): 2566, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37142562

RESUMO

Dietary factors influence male reproductive function in both experimental and epidemiological studies. However, there are currently no specific dietary guidelines for male preconception health. Here, we use the Nutritional Geometry framework to examine the effects of dietary macronutrient balance on reproductive traits in C57BL/6 J male mice. Dietary effects are observed in a range of morphological, testicular and spermatozoa traits, although the relative influence of protein, fat, carbohydrate, and their interactions differ depending on the trait being examined. Interestingly, dietary fat has a positive influence on sperm motility and antioxidant capacity, differing to typical high fat diet studies where calorie content is not controlled for. Moreover, body adiposity is not significantly correlated with any of the reproductive traits measured in this study. These results demonstrate the importance of macronutrient balance and calorie intake on reproductive function and support the need to develop specific, targeted, preconception dietary guidelines for males.


Assuntos
Adiposidade , Carboidratos da Dieta , Animais , Camundongos , Masculino , Camundongos Endogâmicos C57BL , Motilidade dos Espermatozoides , Dieta , Obesidade , Nutrientes , Gorduras na Dieta/farmacologia , Dieta Hiperlipídica/efeitos adversos , Proteínas Alimentares
3.
Int J Pharm ; 572: 118807, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31678526

RESUMO

During lyophilisation cycle design, primary drying parameters (chamber pressure and shelf temperature) are adjusted to maximize the sublimation rate and prevent cake collapse, by maintaining the product continuously below its critical temperatures. The objective of this study was to employ mixture design of experiments to generate empirical models capable of predicting glass transition of the maximally freeze concentrated solution (Tg') and collapse temperature (Tc) of amorphous protein (BSA and IgG1) formulations. Additionally, the models developed aid the design of high concentration protein formulations with maximised critical temperatures to obtain shorter and more cost-effective lyophilisation cycles. Formulations contain sucrose as cryo/lyo-protectant and arginine/arginine-HCl as multifunctional excipient (e.g. solubility enhancer, viscosity and aggregation suppressor). The impact of formulation components at varied ratios on critical temperatures was evaluated; the amorphous excipients decrease critical temperatures, on the contrary, the protein increases critical temperatures. The robustness of the empirical models generated with BSA formulations was verified with BSA and IgG1 formulations. The models showed greater accuracy in predicting Tg' than the Fox-Flory equation. For the first time, empirical models are reported to predict both critical temperatures. Finally, unconventional collapse events observed for formulations with and without arginine/arginine-HCl at different protein concentrations are also discussed.


Assuntos
Liofilização , Imunoglobulina G/química , Soroalbumina Bovina/química , Tecnologia Farmacêutica/métodos , Temperatura , Arginina/química , Crioprotetores/química , Composição de Medicamentos , Excipientes/química , Pressão , Agregados Proteicos , Solubilidade , Sacarose/química , Viscosidade , Vitrificação
4.
Eur J Pharm Biopharm ; 131: 8-24, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30006246

RESUMO

The study presented is a comprehensive overview of commercial parenteral protein formulations, approved by the European Medicines Agency (EMA), 1995-2018. The objective of this overview was to analyse current trends in the design of commercial parenteral protein products and thereby support formulation scientists in the design of new formulations. The main data source was the publicly available European Public Assessment Reports (EPARs) published by the EMA for each authorised product. An analysis of the percentage of formulations in a liquid and lyophilised form was conducted. In addition, the number of products containing individual excipients, classified into functional categories is provided. Finally, the overview includes comprehensive details of product compositions obtained from EMA, US Food and Drug Administration (FDA) and product Marketing Authorisation Holder. Data analysis highlighted trends in the number of products approved, and the higher percentage of liquid parenteral protein formulations (66%) compared to lyophilised formulations (34%). This overview identifies the most commonly incorporated excipients employed as buffering agents, stabilisers/bulking agents, surfactants, preservatives and tonicifiers, including their concentration ranges of use in both liquid and lyophilised formulation approaches. Finally, antibody-based formulations were a particular focus of this overview. The relationship between parenteral routes of administration and antibody concentrations in approved products was also investigated.


Assuntos
Composição de Medicamentos/métodos , Infusões Parenterais , Proteínas/administração & dosagem , Aprovação de Drogas , União Europeia , Excipientes , Humanos , Proteínas/química
5.
J Evol Biol ; 30(9): 1633-1643, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28386961

RESUMO

The highly conserved effect of dietary protein restriction on lifespan and ageing is observed in both sexes and across a vast range of taxa. This extension of lifespan is frequently accompanied by a reduction in female fecundity, and it has been hypothesized that individuals may reallocate resources away from reproduction and into somatic maintenance. However, effects of dietary protein restriction on male reproduction are less consistent, suggesting that these effects may depend on other environmental parameters. Using the neriid fly, Telostylinus angusticollis, we examined age-specific effects of adult dietary protein restriction on male post-copulatory reproductive performance (fecundity and offspring viability). To explore the context dependence of these effects, we simultaneously manipulated male larval diet and adult mating history. We found that protein-restricted males sired less viable offspring at young ages, but offspring viability increased with paternal age and eventually exceeded that of fully fed males. The number of eggs laid by females was not affected by male dietary protein, whereas egg hatching success was subject to a complex interaction of male adult diet, age, larval diet and mating history. These findings suggest that effects of protein restriction on male reproduction are highly context dependent and cannot be explained by a simple reallocation of resources from reproduction to somatic maintenance. Rather, these effects appear to involve changes in the scheduling of male reproductive investment with age.


Assuntos
Copulação , Dieta , Proteínas Alimentares , Dípteros , Reprodução , Animais , Feminino , Fertilidade , Larva , Masculino
6.
Am J Transplant ; 16(10): 3007-3015, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27140676

RESUMO

Cardiac allograft vasculopathy (CAV) is a leading cause of mortality after heart transplantation. Noninvasive imaging techniques used in CAV evaluation have important limitations. In a cross-sectional study, we investigated perfusion cardiac magnetic resonance (CMR) imaging to determine an optimal myocardial perfusion reserve index (MPR) cutoff for detecting CAV using receiver operating characteristic curve analysis. We evaluated CMR performance using sensitivity, specificity and likelihood ratio analysis. We included 29 patients (mean 5 ± 4 years after transplant) scheduled for coronary angiography with intravascular ultrasound (IVUS) who completed CMR. CAV was defined as maximal intimal thickness (MIT) >0.5 mm by IVUS of the left anterior descending artery. CAV was evident in 19 patients (70%) on IVUS (mean MIT 0.82 ± 0.42 mm). MPR was significantly lower in patients with MIT ≥0.50 mm (1.35 ± 0.23 vs. 1.71 ± 0.45, p = 0.013). There was moderate inverse correlation between MPR and MIT (r = -0.36, p = 0.075). The optimal MPR cutoff ≤1.68 for predicting CAV showed sensitivity of 100%, specificity of 63%, a negative predictive value of 100%, a positive predictive value of 86% and a positive likelihood ratio of 2.7. An MPR ≤1.68 has high negative predictive value, suggesting its potential as a test to rule out CAV.


Assuntos
Doença da Artéria Coronariana/cirurgia , Transplante de Coração/efeitos adversos , Angiografia por Ressonância Magnética/métodos , Doenças Vasculares/diagnóstico , Adulto , Aloenxertos , Angiografia Coronária , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Doenças Vasculares/diagnóstico por imagem , Doenças Vasculares/etiologia
7.
Sci Rep ; 5: 11783, 2015 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-26119686

RESUMO

Restriction of nutrients in the adult diet extends lifespan across a diverse range of species, but less is known about the long-term effects of developmental dietary restriction. In particular, it is not known whether adult lifespan is influenced by developmental caloric restriction or macronutrient balance. We used the nutritional geometry approach to independently manipulate protein and carbohydrate contents of the larval diet in the neriid fly, Telostylinus angusticollis, and measured adult lifespan. We found that adult male and female lifespan was shortest when larvae were fed a protein restricted diet. Thus, protein restriction in the larval diet has the opposite effect of protein restriction in the adult diet (which prolongs life in this species and across a wide range of taxa). Adult lifespan was unaffected by larval dietary carbohydrate. These patterns persisted after controlling for larval diet effects on adult body size. We propose that larval and adult protein sources are used for distinct metabolic tasks: during development, dietary protein is used to build a durable soma that enhances adult lifespan, although excessive protein consumption partially reverses this effect.


Assuntos
Proteínas Alimentares/administração & dosagem , Dípteros/fisiologia , Longevidade/fisiologia , Metamorfose Biológica/fisiologia , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Tamanho Corporal/efeitos dos fármacos , Tamanho Corporal/fisiologia , Proteínas Alimentares/farmacologia , Dípteros/efeitos dos fármacos , Feminino , Larva/efeitos dos fármacos , Larva/fisiologia , Longevidade/efeitos dos fármacos , Masculino , Metamorfose Biológica/efeitos dos fármacos , Fatores de Tempo
8.
Cardiovasc J Afr ; 23(8): e9-e10, 2012 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-23044529

RESUMO

A 24-year-old female presented to her general practitioner with shortness of breath. She was referred for an echocardiogram, which demonstrated features suggestive of a right coronary artery fistula, and referred to our institute. We performed a contrast-enhanced, prospectively triggered cardiac CT angiogram, which demonstrated the primary and secondary features of anomalous left coronary artery arising from the pulmonary artery (ALCAPA), also known as the Bland-White-Garland syndrome, a rare congenital abnormality of the origin of the left main coronary artery.


Assuntos
Anomalias dos Vasos Coronários/diagnóstico , Dispneia/diagnóstico , Cardiopatias Congênitas/diagnóstico , Artéria Pulmonar/anormalidades , Adulto , Anomalias dos Vasos Coronários/diagnóstico por imagem , Dispneia/etiologia , Feminino , Cardiopatias Congênitas/complicações , Humanos , Artéria Pulmonar/diagnóstico por imagem , Radiografia , Síndrome , Adulto Jovem
9.
Radiología (Madr., Ed. impr.) ; 54(1): 85-87, ene.-feb. 2012. ilus
Artigo em Espanhol | IBECS | ID: ibc-96586

RESUMO

La ausencia congénita del tronco coronario izquierdo es una de las anomalías de arterias coronarias más raras. Presentamos un caso en el que se sospechó este diagnósticomediante angiografía coronaria, confirmándose mediantetomografíacomputarizada (TC) volumétricacardíaca adquirida en un solo latido (AU)


The congenital absence of the left coronary trunk is one of the rarest anomalies of the coronary artery. We present a case in which this anomaly was suspected at cardiac catheterization and confirmed at volumetric cardiac computed tomography (CT) with a single heart beat (AU)


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada de Feixe Cônico/métodos , Tomografia Computadorizada de Feixe Cônico , Anomalias dos Vasos Coronários , Angiografia Coronária/métodos , Angiografia Coronária/instrumentação , Angiografia Coronária/tendências , Angiografia Coronária
10.
Ir J Med Sci ; 181(1): 99-104, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21959951

RESUMO

BACKGROUND: The practice of fasting from midnight prior to surgery is an outdated one. AIMS: The aim of this study was to assess the impact of an evidence-based protocol for reduced preoperative fasting on fasting times, patient safety, and comfort. METHODS: A non-randomised case-control study of preoperative fasting times among adult surgical patients undergoing elective procedures was conducted. Consecutive patients were allocated to a reduced preoperative fasting protocol allowing fluids and solids up to 2 and 6 h prior to anaesthesia, respectively (n = 21). These were compared to control patients identified from an historic study of preoperative fasting times who followed the traditional fast from midnight (n = 29). Fasting times and details of patients' subjective comfort were collected using an interview-assisted questionnaire. Incidence of intraoperative aspirations was obtained from anaesthetic records. RESULTS: Significant reductions in fasting times for fluids (p = 0.000) and solids (p = 0.000) were achieved following implementation of the fasting protocol. Less preoperative thirst (0.000), headache (0.012) and nausea (0.015) were reported by those who had a shorter fast. Intraoperative aspiration did not occur in either group. CONCLUSION: Implementation of this protocol for reduced preoperative fasting achieved an appreciable reduction in fasting times and enhanced patient comfort. Patient safety was not compromised. Further modifications of our protocols are necessary to meet the international best practice. We recommend its implementation across all surgical groups in our institution.


Assuntos
Procedimentos Cirúrgicos Eletivos , Jejum , Período Pré-Operatório , Estudos de Casos e Controles , Medicina Baseada em Evidências , Humanos , Fatores de Tempo
11.
Radiologia ; 54(1): 85-7, 2012.
Artigo em Espanhol | MEDLINE | ID: mdl-21665234

RESUMO

The congenital absence of the left coronary trunk is one of the rarest anomalies of the coronary artery. We present a case in which this anomaly was suspected at cardiac catheterization and confirmed at volumetric cardiac computed tomography (CT) with a single heart beat.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Anomalias dos Vasos Coronários/diagnóstico por imagem , Idoso , Tomografia Computadorizada de Feixe Cônico/métodos , Humanos , Masculino
12.
Crit Rev Food Sci Nutr ; 50(10): 951-68, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21108075

RESUMO

Microencapsulation has been developed by the pharmaceutical industry as a means to control or modify the release of drug substances from drug delivery systems. In drug delivery systems microencapsulation is used to improve the bioavailability of drugs, control drug release kinetics, minimize drug side effects, and mask the bitter taste of drug substances. The application of microencapsulation has been extended to the food industry, typically for controlling the release of flavorings and the production of foods containing functional ingredients (e.g. probiotics and bioactive ingredients). Compared to the pharmaceutical industry, the food industry has lower profit margins and therefore the criteria in selecting a suitable microencapsulation technology are more stringent. The type of microcapsule (reservoir and matrix systems) produced and its resultant release properties are dependent on the microencapsulation technology, in addition to the physicochemical properties of the core and the shell materials. This review discusses the factors that affect the release of bioactive ingredients from microcapsules produced by different microencapsulation technologies. The key criteria in selecting a suitable microencapsulation technology are also discussed. Two of the most common physical microencapsulation technologies used in pharmaceutical processing, fluidized-bed coating, and extrusion-spheronization are explained to highlight how they might be adapted to the microencapsulation of functional bioactive ingredients in the food industry.


Assuntos
Produtos Biológicos/química , Composição de Medicamentos/métodos , Tecnologia de Alimentos/métodos , Alimentos Fortificados , Cápsulas/química , Alimentos , Preparações Farmacêuticas
13.
J Biomed Mater Res B Appl Biomater ; 95(1): 141-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20737556

RESUMO

A series of doped apatites have been deposited onto titanium (V) substrates using a novel ambient temperature blasting process. The potential of these deposited doped apatites as non-colonizing osteoconductive coatings has been evaluated in vitro. XPS, EDX, and gravimetric analysis demonstrated that a high degree of coating incorporation was observed for each material. The modified surfaces were found to produce osteoblast proliferation comparable to, or better than, a hydroxyapatite finish. Promising levels of initial microbial inhibition were observed from the Sr- and Ag-doped surfaces, with the strontium showing prolonged ability to reduce bacteria numbers over a 30-day period. Ion elution profiles have been characterized and linked to the microbial response and based on the results obtained, mechanisms of kill have been suggested. In this study, the direct contact of coated substrate surfaces with microbes was observed to be a significant contributing factor to the antimicrobial performance and the anticolonizing activity. The silver substituted apatite was observed to out-perform both the SrA and ZnA in terms of biofilm inhibition.


Assuntos
Antibacterianos/química , Apatitas/química , Apatitas/farmacologia , Materiais Revestidos Biocompatíveis/química , Osteoblastos/citologia , Osteogênese/efeitos dos fármacos , Titânio/química , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Linhagem Celular , Proliferação de Células , Materiais Revestidos Biocompatíveis/farmacologia , Humanos , Prata/farmacologia , Estrôncio/farmacologia , Propriedades de Superfície , Zinco/farmacologia
14.
Health Technol Assess ; 11(49): iii-iv, ix-115, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18021576

RESUMO

OBJECTIVES: To assess the acceptability and feasibility of functional tests as a gateway to angiography for management of coronary artery disease (CAD), the ability of diagnostic strategies to identify patients who should undergo revascularisation, patient outcomes in each diagnostic strategy, and the most cost-effective diagnostic strategy for patients with suspected or known CAD. DESIGN: A rapid systematic review of economic evaluations of alternative diagnostic strategies for CAD was carried out. A pragmatic and generalisable randomised controlled trial was undertaken to assess the use of the functional cardiac tests: angiography (controls); single photon emission computed tomography (SPECT); magnetic resonance imaging (MRI); stress echocardiography. SETTING: The setting was Papworth Hospital NHS Foundation Trust, a tertiary cardiothoracic referral centre. PARTICIPANTS: Patients with suspected or known CAD and an exercise test result that required non-urgent angiography. INTERVENTIONS: Patients were randomised to one of the four initial diagnostic tests. MAIN OUTCOME MEASURES: Eighteen months post-randomisation: exercise time (modified Bruce protocol); cost-effectiveness compared with angiography (diagnosis, treatment and follow-up costs). The aim was to demonstrate equivalence in exercise time between those randomised to functional tests and those randomised to angiography [defined as the confidence interval (CI) for mean difference from angiography within 1 minute]. RESULTS: The 898 patients were randomised to angiography (n = 222), SPECT (n = 224), MRI (n = 226) or stress echo (n = 226). Initial diagnostic tests were completed successfully with unequivocal results for 98% of angiography, 94% of SPECT (p = 0.05), 78% of MRI (p < 0.001) and 90% of stress echocardiography patients (p < 0.001). Some 22% of SPECT patients, 20% of MRI patients and 25% of stress echo patients were not subsequently referred for an angiogram. Positive functional tests were confirmed by positive angiography in 83% of SPECT patients, 89% of MRI patients and 84% of stress echo patients. Negative functional tests were followed by positive angiograms in 31% of SPECT patients, 52% of MRI patients and 48% of stress echo patients tested. The proportions that had coronary artery bypass graft surgery were 10% (angiography), 11% (MRI) and 13% (SPECT and stress echo) and percutaneous coronary intervention 25% (angiography), 18% (SPECT) and 23% (MRI and stress echo). At 18 months, comparing SPECT and stress echo with angiography, a clinically significant difference in total exercise time can be ruled out. The MRI group had significantly shorter mean total exercise time of 35 seconds and the upper limit of the CI was 1.14 minutes less than in the angiography group, so a difference of at least 1 minute cannot be ruled out. At 6 months post-treatment, SPECT and angiography had equivalent mean exercise time. Compared with angiography, the MRI and stress echo groups had significantly shorter mean total exercise time of 37 and 38 seconds, respectively, and the upper limit of both CIs was 1.16 minutes, so a difference of at least 1 minute cannot be ruled out. The differences were mainly attributable to revascularised patients. There were significantly more non-fatal adverse events in the stress echo group, mostly admissions for chest pain, but no significant difference in the number of patients reporting events. Mean (95% CI) total additional costs over 18 months, compared with angiography, were 415 pounds (-310 pounds to 1084 pounds) for SPECT, 426 pounds (-247 pounds to 1088 pounds) for MRI and 821 pounds (10 pounds to 1715 pounds) for stress echocardiography, with very little difference in quality-adjusted life-years (QALYs) amongst the groups (less than 0.04 QALYs over 18 months). Cost-effectiveness was mainly influenced by test costs, clinicians' willingness to trust negative functional tests and by a small number of patients who had a particularly difficult clinical course. CONCLUSIONS: Between 20 and 25% of patients can avoid invasive testing using functional testing as a gateway to angiography, without substantial effects on outcomes. The SPECT strategy was as useful as angiography in identifying patients who should undergo revascularisation and the additional cost was not significant, in fact it would be reduced further by restricting the rest test to patients who have a positive stress test. MRI had the largest number of test failures and, in this study, had the least practical use in screening patients with suspected CAD, although it had similar outcomes to stress echo and is still an evolving technology. Stress echo patients had a 10% test failure rate, significantly shorter total exercise time and time to angina at 6 months post-treatment, and a greater number of adverse events, leading to significantly higher costs. Given the level of skill required for stress echo, it may be best to reserve this test for those who have a contraindication to SPECT and are unable or unwilling to have MRI. Further research, using blinded reassessment of functional test results and angiograms, is required to formally assess diagnostic accuracy. Longer-term cost-effectiveness analysis, and further studies of MRI and new generation computed tomography are also required.


Assuntos
Doença da Artéria Coronariana/diagnóstico , Testes de Função Cardíaca/economia , Revascularização Miocárdica/economia , Idoso , Intervalos de Confiança , Angiografia Coronária/economia , Doença da Artéria Coronariana/economia , Doença da Artéria Coronariana/terapia , Análise Custo-Benefício , Ecocardiografia/economia , Inglaterra , Teste de Esforço/economia , Feminino , Testes de Função Cardíaca/métodos , Testes de Função Cardíaca/estatística & dados numéricos , Humanos , Angiografia por Ressonância Magnética/economia , Masculino , Pessoa de Meia-Idade , Revascularização Miocárdica/efeitos adversos , Revascularização Miocárdica/estatística & dados numéricos , Avaliação de Processos e Resultados em Cuidados de Saúde , Anos de Vida Ajustados por Qualidade de Vida , Medição de Risco , Perfil de Impacto da Doença , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único
15.
Clin Radiol ; 61(3): 225-36, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16488204

RESUMO

Cardiac magnetic resonance imaging is rapidly emerging as an exciting and important technique for the investigation of congenital and acquired heart disease. This article focuses in particular on recent developments in the field of adenosine stress myocardial perfusion as well as addressing the many applications of 'delayed enhancement' imaging.


Assuntos
Cardiopatias/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adenosina , Animais , Coração , Humanos , Sensibilidade e Especificidade
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