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1.
Front Neurosci ; 18: 1379658, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38803685

RESUMO

Glioblastoma multiforme (GBM) is one of the most common and lethal forms of brain cancer, carrying a very poor prognosis (median survival of ~15 months post-diagnosis). Treatment typically involves invasive surgical resection of the tumour mass, followed by radiotherapy and adjuvant chemotherapy using the alkylating agent temozolomide, but over half of patients do not respond to this drug and considerable resistance is observed. Tumour heterogeneity is the main cause of therapeutic failure, where diverse progenitor glioblastoma stem cell (GSC) lineages in the microenvironment drive tumour recurrence and therapeutic resistance. The apelin receptor is a class A GPCR that binds two endogenous peptide ligands, apelin and ELA, and plays a role in the proliferation and survival of cancer cells. Here, we used quantitative whole slide immunofluorescent imaging of human GBM samples to characterise expression of the apelin receptor and both its ligands in the distinct GSC lineages, namely neural-progenitor-like cells (NPCs), oligodendrocyte-progenitor-like cells (OPCs), and mesenchymal-like cells (MES), as well as reactive astrocytic cells. The data confirm the presence of the apelin receptor as a tractable drug target that is common across the key cell populations driving tumour growth and maintenance, offering a potential novel therapeutic approach for patients with GBM.

2.
Front Endocrinol (Lausanne) ; 13: 797438, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35222269

RESUMO

Background: Many individuals with type 1 diabetes retain residual beta-cell function. Sustained endogenous insulin and C-peptide secretion is associated with reduced diabetes related complications, but underlying mechanisms remain unclear. Lower circulating numbers of endothelial and hematopoietic progenitor cells (EPCs and HPCs), and the inability to increase the count of these cells in response to exercise, are also associated with increased diabetes complications and cardiovascular disease. It is unknown whether residual beta-cell function influences HPCs and EPCs. Thus, this study examined the influence of residual beta-cell function in type 1 diabetes upon exercise-induced changes in haematopoietic (HPCs) and endothelial progenitor cells (EPCs). Methods: Participants with undetectable stimulated C-peptide (n=11; Cpepund), 10 high C-peptide (Cpephigh; >200 pmol/L), and 11 non-diabetes controls took part in this observational exercise study, completing 45 minutes of intensive walking at 60% V˙O2peak . Clinically significant HPCs (CD34+) and EPCs (CD34+VEGFR2+) phenotypes for predicting future adverse cardiovascular outcomes, and subsequent cell surface expression of chemokine receptor 4 (CXCR4) and 7 (CXCR7), were enumerated at rest and immediately post-exercise by flow cytometry. Results: Exercise increased HPCs and EPCs phenotypes similarly in the Cpephigh and control groups (+34-121% across phenotypes, p<0.04); but Cpepund group did not significantly increase from rest, even after controlling for diabetes duration. Strikingly, the post-exercise Cpepund counts were still lower than Cpephigh at rest. Conclusions: Residual beta-cell function is associated with an intact exercise-induced HPCs and EPCs mobilisation. As key characteristics (age, fitness, HbA1c) were similar between groups, the mechanisms underpinning the absent mobilisation within those with negative C-peptide, and the vascular implications, require further investigation.


Assuntos
Aptidão Cardiorrespiratória , Diabetes Mellitus Tipo 1 , Células Progenitoras Endoteliais , Diabetes Mellitus Tipo 1/metabolismo , Células Progenitoras Endoteliais/metabolismo , Exercício Físico/fisiologia , Hemoglobinas Glicadas/metabolismo , Humanos
3.
Front Endocrinol (Lausanne) ; 12: 696977, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34220720

RESUMO

Purpose: Elevated postprandial glycaemia [PPG] increases the risk of cardiometabolic complications in insulin-resistant, centrally obese individuals. Therefore, strategies that improve PPG are of importance for this population. Consuming large doses of whey protein [WP] before meals reduces PPG by delaying gastric emptying and stimulating the secretion of the incretin peptides, glucose-dependent insulinotropic polypeptide [GIP] and glucagon-like peptide 1 [GLP-1]. It is unclear if these effects are observed after smaller amounts of WP and what impact central adiposity has on these gastrointestinal processes. Methods: In a randomised-crossover design, 12 lean and 12 centrally obese adult males performed two 240 min mixed-meal tests, ~5-10 d apart. After an overnight fast, participants consumed a novel, ready-to-drink WP shot (15 g) or volume-matched water (100 ml; PLA) 10 min before a mixed-nutrient meal. Gastric emptying was estimated by oral acetaminophen absorbance. Interval blood samples were collected to measure glucose, insulin, GIP, GLP-1, and acetaminophen. Results: WP reduced PPG area under the curve [AUC0-60] by 13 and 18.2% in the centrally obese and lean cohorts, respectively (both p <0.001). In both groups, the reduction in PPG was accompanied by a two-three-fold increase in GLP-1 and delayed gastric emptying. Despite similar GLP-1 responses during PLA, GLP-1 secretion during the WP trial was ~27% lower in centrally obese individuals compared to lean (p = 0.001). In lean participants, WP increased the GLP-1ACTIVE/TOTAL ratio comparative to PLA (p = 0.004), indicative of reduced GLP-1 degradation. Conversely, no treatment effects for GLP-1ACTIVE/TOTAL were seen in obese subjects. Conclusion: Pre-meal ingestion of a novel, ready-to-drink WP shot containing just 15 g of dietary protein reduced PPG in lean and centrally obese males. However, an attenuated GLP-1 response to mealtime WP and increased incretin degradation might impact the efficacy of nutritional strategies utilising the actions of GLP-1 to regulate PPG in centrally obese populations. Whether these defects are caused by an individual's insulin resistance, their obese state, or other obesity-related ailments needs further investigation. Clinical Trial Registration: ISRCTN.com, identifier [ISRCTN95281775]. https://www.isrctn.com/.


Assuntos
Glicemia/metabolismo , Hormônios Gastrointestinais/metabolismo , Obesidade Abdominal/dietoterapia , Proteínas do Soro do Leite/farmacologia , Adulto , Glicemia/efeitos dos fármacos , Peptídeo C/sangue , Estudos Cross-Over , Ingestão de Alimentos , Inglaterra , Alimentos Formulados , Esvaziamento Gástrico/fisiologia , Polipeptídeo Inibidor Gástrico/sangue , Polipeptídeo Inibidor Gástrico/efeitos dos fármacos , Glucagon/sangue , Peptídeo 1 Semelhante ao Glucagon/sangue , Peptídeo 1 Semelhante ao Glucagon/efeitos dos fármacos , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Obesidade Abdominal/sangue , Obesidade Abdominal/metabolismo , Período Pós-Prandial/efeitos dos fármacos , Magreza/sangue , Magreza/metabolismo , Proteínas do Soro do Leite/administração & dosagem , Adulto Jovem
4.
Sci Rep ; 11(1): 14502, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267242

RESUMO

Exercise mobilizes angiogenic cells, which stimulate vascular repair. However, limited research suggests exercise-induced increase of endothelial progenitor cell (EPCs) is completely lacking in type 1 diabetes (T1D). Clarification, along with investigating how T1D influences exercise-induced increases of other angiogenic cells (hematopoietic progenitor cells; HPCs) and cell surface expression of chemokine receptor 4 (CXCR4) and 7 (CXCR7), is needed. Thirty T1D patients and 30 matched non-diabetes controls completed 45 min of incline walking. Circulating HPCs (CD34+, CD34+CD45dim) and EPCs (CD34+VEGFR2+, CD34+CD45dimVEGFR2+), and subsequent expression of CXCR4 and CXCR7, were enumerated by flow cytometry at rest and post-exercise. Counts of HPCs, EPCs and expression of CXCR4 and CXCR7 were significantly lower at rest in the T1D group. In both groups, exercise increased circulating angiogenic cells. However, increases was largely attenuated in the T1D group, up to 55% lower, with CD34+ (331 ± 437 Δcells/mL vs. 734 ± 876 Δcells/mL p = 0.048), CD34+VEGFR2+ (171 ± 342 Δcells/mL vs. 303 ± 267 Δcells/mL, p = 0.006) and CD34+VEGFR2+CXCR4+ (126 ± 242 Δcells/mL vs. 218 ± 217 Δcells/mL, p = 0.040) significantly lower. Exercise-induced increases of angiogenic cells is possible in T1D patients, albeit attenuated compared to controls. Decreased mobilization likely results in reduced migration to, and repair of, vascular damage, potentially limiting the cardiovascular benefits of exercise.Trial registration: ISRCTN63739203.


Assuntos
Diabetes Mellitus Tipo 1/sangue , Células Progenitoras Endoteliais/fisiologia , Exercício Físico/fisiologia , Receptores CXCR4/metabolismo , Receptores CXCR/metabolismo , Adulto , Diabetes Mellitus Tipo 1/fisiopatologia , Feminino , Células-Tronco Hematopoéticas/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/sangue
5.
Mol Pharm ; 18(4): 1530-1543, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33656882

RESUMO

The aim of the study was to investigate the impact of Crohn's disease (CD) on the performance of a lipid-based formulation of ciprofloxacin in a complex gastrointestinal simulator (TIM-1, TNO) and to compare the luminal environment in terms of bile salt and lipid composition in CD and healthy conditions. CD conditions were simulated in the TIM-1 system with a reduced concentration of porcine pancreatin and porcine bile. The bioaccessibility of ciprofloxacin was similar in simulated CD and healthy conditions considering its extent as well as its time course in the jejunum and ileum filtrate. Differences were observed in terms of the luminal concentration of triglycerides, monoglycerides, and fatty acids in the different TIM-1 compartments, indicating a reduction and delay in the lipolysis of formulation excipients in CD. The quantitative analysis of bile salts revealed higher concentrations for healthy conditions (standard TIM-1 fasted-state protocol) in the duodenum and jejunum TIM-1 compartments compared to published data in human intestinal fluids of healthy subjects. The reduced concentrations of bile salts in simulated CD conditions correspond to the levels observed in human intestinal fluids of healthy subjects in the fasted state.A lipidomics approach with ultra performance liquid chromatography (UPLC)/mass spectrometry (MS) has proven to be a time-efficient method to semiquantitatively analyze differences in fatty acid and bile salt levels between healthy and CD conditions. The dynamic luminal environment in CD and healthy conditions after administration of a lipid-based formulation can be simulated using the TIM-1 system. For ciprofloxacin, an altered luminal lipid composition had no impact on its performance indicating a low risk of altered performance in CD patients.


Assuntos
Ciprofloxacina/farmacocinética , Doença de Crohn/tratamento farmacológico , Excipientes/química , Mucosa Intestinal/metabolismo , Lipídeos/química , Administração Oral , Animais , Ácidos e Sais Biliares/metabolismo , Ciprofloxacina/administração & dosagem , Doença de Crohn/patologia , Jejum , Voluntários Saudáveis , Humanos , Íleo/metabolismo , Íleo/patologia , Mucosa Intestinal/patologia , Jejuno/metabolismo , Jejuno/patologia , Lipidômica , Pancreatina/metabolismo , Suspensões , Suínos , Distribuição Tecidual
6.
J Trauma Acute Care Surg ; 83(2): 241-248, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28731937

RESUMO

BACKGROUND: There is no consensus on reporting nonmortality trauma complications in a graded manner. The Clavien-Dindo scale of complications was originally for elective surgery and requires adaptation to provide meaningful data for trauma patients. In particular, the original score does not account for those treated without surgery. We report an adapted Clavien-Dindo in trauma (ACDiT) scale and apply it to patients managed operatively and nonoperatively. METHODS: A combined prospective and retrospective international multicenter observational study was undertaken to apply the ACDiT scale to 484 trauma patients at three university teaching hospitals (Birmingham, England (n = 303); Houston, Texas (n = 113); and Glasgow, Scotland (n = 68)). These included both intensive care unit (ICU) and non-ICU-managed patients. The Clavien-Dindo scoring system was adapted for trauma patients based on consensus amongst an international collaboration of trauma specialists at these sites. Data included whether initial patients were managed operatively or nonoperatively. Complication grades were compared with hospital-free and ICU-free days as other outcome measures of patient morbidity. RESULTS: Two hundred seventeen (44.8%) of 484 patients experienced complications, of whom 61 (28.1%) of 217 died (grade V). The remainder consisted of grades I (n = 20), II (n = 60), III (n = 24), and IV (n = 52). There was a strong association between higher ACDiT grade category and lower number of hospital-free and ICU-free days (p < 0.01). Eighty-eight patients with complications did not require surgery, validating the score's usefulness in patients managed nonoperatively. CONCLUSION: The ACDiT scale can be used to grade the severity of posttrauma complications in patients managed both operatively and nonoperatively. It provides clinically meaningful data for morbidity and mortality meetings and other quality improvement exercises. LEVEL OF EVIDENCE: Prognostic, level IV.


Assuntos
Índices de Gravidade do Trauma , Ferimentos e Lesões/complicações , Ferimentos e Lesões/mortalidade , Adulto , Causas de Morte , Coleta de Dados/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Análise de Sobrevida , Centros de Traumatologia/estatística & dados numéricos , Ferimentos e Lesões/classificação , Ferimentos e Lesões/terapia , Adulto Jovem
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