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1.
Br J Cancer ; 130(6): 908-924, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38238426

RESUMO

BACKGROUND: Redox signaling caused by knockdown (KD) of Glutathione Peroxidase 2 (GPx2) in the PyMT mammary tumour model promotes metastasis via phenotypic and metabolic reprogramming. However, the tumour cell subpopulations and transcriptional regulators governing these processes remained unknown. METHODS: We used single-cell transcriptomics to decipher the tumour cell subpopulations stimulated by GPx2 KD in the PyMT mammary tumour and paired pulmonary metastases. We analyzed the EMT spectrum across the various tumour cell clusters using pseudotime trajectory analysis and elucidated the transcriptional and metabolic regulation of the hybrid EMT state. RESULTS: Integration of single-cell transcriptomics between the PyMT/GPx2 KD primary tumour and paired lung metastases unraveled a basal/mesenchymal-like cluster and several luminal-like clusters spanning an EMT spectrum. Interestingly, the luminal clusters at the primary tumour gained mesenchymal gene expression, resulting in epithelial/mesenchymal subpopulations fueled by oxidative phosphorylation (OXPHOS) and glycolysis. By contrast, at distant metastasis, the basal/mesenchymal-like cluster gained luminal and mesenchymal gene expression, resulting in a hybrid subpopulation using OXPHOS, supporting adaptive plasticity. Furthermore, p63 was dramatically upregulated in all hybrid clusters, implying a role in regulating partial EMT and MET at primary and distant sites, respectively. Importantly, these effects were reversed by HIF1α loss or GPx2 gain of function, resulting in metastasis suppression. CONCLUSIONS: Collectively, these results underscored a dramatic effect of redox signaling on p63 activation by HIF1α, underlying phenotypic and metabolic plasticity leading to mammary tumour metastasis.


Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Neoplasias Mamárias Animais , Segunda Neoplasia Primária , Animais , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Reprogramação Metabólica , Transição Epitelial-Mesenquimal/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Oxirredução , Linhagem Celular Tumoral , Metástase Neoplásica
2.
PLoS One ; 18(9): e0291029, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37751459

RESUMO

Neurodegenerative diseases encompass a group of debilitating conditions resulting from progressive nerve cell death. Of these, Alzheimer's disease (AD) occurs most frequently, but is currently incurable and has limited treatment success. Late onset AD, the most common form, is highly heritable but is caused by a combination of non-genetic risk factors and many low-effect genetic variants whose disease-causing mechanisms remain unclear. By mining the FinnGen study database of phenome-wide association studies, we identified a rare variant, rs148726219, enriched in the Finnish population that is associated with AD risk and dementia, and appears to have arisen on a common haplotype with older AD-associated variants such as rs429358. The rs148726219 variant lies in an overlapping intron of the FosB proto-oncogene (FOSB) and ERCC excision repair 1 (ERCC1) genes. To understand the impact of this SNP on disease phenotypes, we performed CRISPR/Cas9 editing in a human induced pluripotent stem cell (hiPSC) line to generate isogenic clones harboring heterozygous and homozygous alleles of rs148726219. hiPSC clones differentiated into induced excitatory neurons (iNs) did not exhibit detectable molecular or morphological variation in differentiation potential compared to isogenic controls. However, global transcriptome analysis showed differential regulation of nearby genes and upregulation of several biological pathways related to neuronal function, particularly synaptogenesis and calcium signaling, specifically in mature iNs harboring rs148726219 homozygous and heterozygous alleles. Functional differences in iN circuit maturation as measured by calcium imaging were observed across genotypes. Edited mature iNs also displayed downregulation of unfolded protein response and cell death pathways. This study implicates a phenotypic impact of rs148726219 in the context of mature neurons, consistent with its identification in late onset AD, and underscores a hiPSC-based experimental model to functionalize GWAS-identified variants.


Assuntos
Doença de Alzheimer , Células-Tronco Pluripotentes Induzidas , Humanos , Doença de Alzheimer/metabolismo , Polimorfismo de Nucleotídeo Único , Genótipo , Neurônios
3.
Front Oncol ; 13: 1160167, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37124523

RESUMO

Various natural language processing (NLP) algorithms have been applied in the literature to analyze radiology reports pertaining to the diagnosis and subsequent care of cancer patients. Applications of this technology include cohort selection for clinical trials, population of large-scale data registries, and quality improvement in radiology workflows including mammography screening. This scoping review is the first to examine such applications in the specific context of breast cancer. Out of 210 identified articles initially, 44 met our inclusion criteria for this review. Extracted data elements included both clinical and technical details of studies that developed or evaluated NLP algorithms applied to free-text radiology reports of breast cancer. Our review illustrates an emphasis on applications in diagnostic and screening processes over treatment or therapeutic applications and describes growth in deep learning and transfer learning approaches in recent years, although rule-based approaches continue to be useful. Furthermore, we observe increased efforts in code and software sharing but not with data sharing.

4.
Eur Radiol ; 33(10): 6883-6891, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37083741

RESUMO

OBJECTIVES: To perform a systematic review comparing the diagnostic accuracy of MRI vs. CT for assessing pancreatic ductal adenocarcinoma (PDAC) vascular invasion. METHODS: MEDLINE, EMBASE, Cochrane Central, and Scopus were searched until December 2021 for diagnostic accuracy studies comparing MRI vs. CT to evaluate vascular invasion of pathologically confirmed PDAC in the same patients. Findings on resection or exploratory laparotomy were the preferred reference standard. Data extraction, risk of bias, and applicability assessment were performed by two authors using the Quality Assessment of Diagnostic Accuracy Studies-Comparative Tool. Bivariate random-effects meta-analysis and meta-regression were performed with 95% confidence intervals (95% CI). RESULTS: Three studies were included assessing 474 vessels without vascular invasion and 65 with vascular invasion in 107 patients. All patients were imaged using MRI at ≥ 1.5 T and a pancreatic protocol CT. No difference was shown between MRI and CT for diagnosing PDAC vascular invasion: MRI/CT sensitivity (95% CI) were 71% (47-87%)/74% (56-86%), and specificity were 97% (94-99%)/97% (94-98%). Sources of bias included selection bias from only a subset of CT patients undergoing MRI and verification bias from patients with unresectable disease not confirmed on surgery. No patients received neoadjuvant therapy prior to staging. CONCLUSIONS: Based on limited data, no difference was observed between MRI and pancreatic protocol CT for PDAC vascular invasion assessment. MRI may be an adequate substitute for pancreatic protocol CT in some patients, particularly those who have already had a single-phase CT. Larger and more recent cohort studies at low risk of bias, including patients who have received neoadjuvant therapy, are needed. CLINICAL RELEVANCE STATEMENT: Abdominal MRI performed similarly to pancreatic protocol CT at assessing pancreatic ductal adenocarcinoma vascular invasion, suggesting local staging is adequate in some patients using MRI. More data are needed using larger, more recent cohorts including patients with neoadjuvant treatment. KEY POINTS: • Based on limited data, no difference was found between MRI and pancreatic protocol CT sensitivity and specificity for diagnosing PDAC vascular invasion (p = 0.81, 0.73 respectively). • Risk of bias could be reduced in future PDAC MRI vs CT comparative diagnostic test accuracy research by ensuring all enrolled patients undergo both imaging modalities being compared in random order and regardless of the findings on either modality. • More studies are needed that directly compare the diagnostic performance of MRI and CT for PDAC staging after neoadjuvant therapy.


Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/patologia , Adenocarcinoma/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Imageamento por Ressonância Magnética , Carcinoma Ductal Pancreático/diagnóstico por imagem , Sensibilidade e Especificidade , Testes Diagnósticos de Rotina , Neoplasias Pancreáticas
5.
J Magn Reson Imaging ; 57(5): 1567-1575, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36151888

RESUMO

BACKGROUND: Pancreatic cystic lesions (PCLs) are followed for years due to older and likely biased works demonstrating a strong association with pancreatic carcinoma; more recent data are needed clarifying this relationship. PURPOSE: To determine the association between PCLs on MRI and a synchronous or future diagnosis of pancreatic carcinoma. STUDY TYPE: Single-center retrospective cohort. POPULATION: A total of 192 patients (111 female, 58%) with median age 66 years (range 26-87 years) with PCLs on abdominal MRI from 2011 to 2016. FIELD STRENGTH/SEQUENCES: 1.5 T and 3 T, including T2 WI, T1 WI, diffusion weighted imaging and contrast-enhanced T1 WI. ASSESSMENT: Each PCL was reviewed independently by 2 of 10 fellowship-trained abdominal radiologists. Fukuoka guideline worrisome features and high-risk stigmata were evaluated. Follow-up imaging and clinical notes were reviewed within a system that captures pancreatic carcinoma for the region, for a median follow-up of 67 months (interquartile range: 43-88 months). STATISTICAL TESTS: Pancreatic carcinoma prevalence and incidence rate for future carcinoma with 95% confidence intervals (95% CI). Fisher exact test, logistic regression with odds ratios (OR) and the Wilcoxon rank-sum test were used to assess PCL morphologic features with the Kolmogorov-Smirnov test used to assess for normality. P < 0.05 defined statistical significance. RESULTS: The prevalence of pancreatic carcinoma on initial MRI showing a PCL was 2.4% (95% CI: 0.9%, 5.2%). Thickened/enhancing cyst wall was associated with pancreatic carcinoma, OR 52 (95% CI: 4.5, 1203). Of 189 patients with a PCL but without pancreatic carcinoma at the time of initial MRI, one developed high-grade dysplasia and none developed invasive carcinoma for an incidence rate of 0.97 (95% CI: 0.02, 5.43) and 0 (95% CI: 0, 3.59) cases per 1000 person-years, respectively. DATA CONCLUSION: A low percentage of patients with a PCL on MRI had a pancreatic carcinoma at the time of initial evaluation and none developed carcinoma over a median 67 months of follow-up. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: 5.


Assuntos
Carcinoma , Cisto Pancreático , Neoplasias Pancreáticas , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Retrospectivos , Cisto Pancreático/complicações , Cisto Pancreático/patologia , Neoplasias Pancreáticas/patologia , Imageamento por Ressonância Magnética , Neoplasias Pancreáticas
6.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35193955

RESUMO

In search of redox mechanisms in breast cancer, we uncovered a striking role for glutathione peroxidase 2 (GPx2) in oncogenic signaling and patient survival. GPx2 loss stimulates malignant progression due to reactive oxygen species/hypoxia inducible factor-α (HIF1α)/VEGFA (vascular endothelial growth factor A) signaling, causing poor perfusion and hypoxia, which were reversed by GPx2 reexpression or HIF1α inhibition. Ingenuity Pathway Analysis revealed a link between GPx2 loss, tumor angiogenesis, metabolic modulation, and HIF1α signaling. Single-cell RNA analysis and bioenergetic profiling revealed that GPx2 loss stimulated the Warburg effect in most tumor cell subpopulations, except for one cluster, which was capable of oxidative phosphorylation and glycolysis, as confirmed by coexpression of phosphorylated-AMPK and GLUT1. These findings underscore a unique role for redox signaling by GPx2 dysregulation in breast cancer, underlying tumor heterogeneity, leading to metabolic plasticity and malignant progression.


Assuntos
Neoplasias da Mama/metabolismo , Plasticidade Celular/fisiologia , Glutationa Peroxidase/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Glutationa Peroxidase/genética , Glutationa Peroxidase/fisiologia , Glicólise , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metabolismo/fisiologia , Camundongos , Camundongos Nus , Neovascularização Patológica/genética , Oxirredução , Fosforilação Oxidativa , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
8.
JCI Insight ; 6(24)2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34784301

RESUMO

BACKGROUNDSkeletal muscle maladaptation accompanies chronic kidney disease (CKD) and negatively affects physical function. Emphasis in CKD has historically been placed on muscle fiber-intrinsic deficits, such as altered protein metabolism and atrophy. However, targeted treatment of fiber-intrinsic dysfunction has produced limited improvement, whereas alterations within the fiber-extrinsic environment have scarcely been examined.METHODSWe investigated alterations to the skeletal muscle interstitial environment with deep cellular phenotyping of biopsies from patients with CKD and age-matched controls and performed transcriptome profiling to define the molecular underpinnings of CKD-associated muscle impairments. We examined changes in muscle maladaptation following initiation of dialysis therapy for kidney failure.RESULTSPatients with CKD exhibited a progressive fibrotic muscle phenotype, which was associated with impaired regenerative capacity and lower vascular density. The severity of these deficits was strongly associated with the degree of kidney dysfunction. Consistent with these profound deficits, CKD was associated with broad alterations to the muscle transcriptome, including altered ECM organization, downregulated angiogenesis, and altered expression of pathways related to stem cell self-renewal. Remarkably, despite the seemingly advanced nature of this fibrotic transformation, dialysis treatment rescued these deficits, restoring a healthier muscle phenotype. Furthermore, after accounting for muscle atrophy, strength and endurance improved after dialysis initiation.CONCLUSIONThese data identify a dialysis-responsive muscle fibrotic phenotype in CKD and suggest the early dialysis window presents a unique opportunity of improved muscle regenerative capacity during which targeted interventions may achieve maximal impact.TRIAL REGISTRATIONNCT01452412FUNDINGNIH, NIH Clinical and Translational Science Awards (CTSA), and Einstein-Mount Sinai Diabetes Research Center.


Assuntos
Fibrose/etiologia , Doenças Musculares/etiologia , Diálise Renal/métodos , Insuficiência Renal Crônica/complicações , Estudos de Casos e Controles , Feminino , Fibrose/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Musculares/patologia , Insuficiência Renal Crônica/patologia , Insuficiência Renal Crônica/terapia , Fatores de Risco
9.
Abdom Radiol (NY) ; 46(3): 1027-1033, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32939634

RESUMO

PURPOSE: To determine equivalency of multi-slice 3D CTTA and single slice 2D CTTA of pancreas adenocarcinoma. METHODS: This retrospective study was research ethics board approved. Untreated pancreas adenocarcinomas were segmented on CT in 128 consecutive patients. Tumor segmentation was compared using two techniques: 3D segmentation by contouring all visible tumor in a 3D volume, and 2D segmentation using only a single axial image. First-order CTTA features including mean, minimum, maximum Hounsfield units (HU), standard deviation, skewness, kurtosis, entropy, and second-order gray-level co-occurrence matrix (GLCM) features homogeneity, contrast, correlation, entropy and dissimilarity were extracted. Median values were compared using the Mann-Whitney U test with Holm-Bonferroni correction. Kendall's Rank Correlation Tau assessed for correlation, and agreement was calculated using intraclass correlation coefficients (ICC) using a two-way model with single rating and absolute agreement. Statistical significance defined as P < 0.05. RESULTS: The median values of CTTA features differed significantly between 3 and 2D segmentations for all of the evaluated features except for mean attenuation, standard deviation and skewness (P = 0.2979 each). 3D and 2D segmentations had moderate correlation for mean attenuation (R = 0.69, P < 0.01), while all other features demonstrated poor to fair correlation. Agreement between 3 and 2D segmentations was good for mean attenuation (ICC: 0.87, P < 0.01), moderate for minimum (ICC: 0.65, P < 0.01) and standard deviation (ICC: 0.56, P < 0.01), and poor for all other features. CONCLUSION: While pancreas adenocarcinoma CTTA features obtained using 3D and 2D segmentation have multiple associations with clinically relevant outcomes, these segmentation techniques are likely not interchangeable other than for mean HU.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Adenocarcinoma/diagnóstico por imagem , Humanos , Pâncreas/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
10.
J Comput Assist Tomogr ; 44(2): 188-192, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32195797

RESUMO

OBJECTIVE: The aim of this study was to determine if texture analysis can classify liver observations likely to be hepatocellular carcinoma based on the Liver Imaging Reporting and Data System (LI-RADS) using single portal venous phase computed tomography. METHODS: This research ethics board-approved retrospective cohort study included 64 consecutive LI-RADS observations. Individual observation texture analysis features were compared using Kruskal-Wallis and 2 sample t tests. Logistic regression was used for prediction of LI-RADS group. Diagnostic accuracy was assessed using receiver operating characteristic curves and Youden method. RESULTS: Multiple texture features were associated with LI-RADS including the mean HU (P = 0.003), median (P = 0.002), minimum (P = 0.010), maximum (P = 0.013), standard deviation (P = 0.009), skewness (P = 0.007), and entropy (P < 0.001). On logistic regression, LI-RADS group could be predicted with area under the curve, sensitivity, and specificity of 0.98, 96%, and 100%, respectively. CONCLUSIONS: Texture analysis features on portal venous phase computed tomography can identify liver observations likely to be hepatocellular carcinoma, which may preclude the need to recall some patients for additional multiphase imaging.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Sistemas de Informação em Radiologia , Tomografia Computadorizada por Raios X/métodos , Idoso , Estudos de Coortes , Feminino , Humanos , Fígado/diagnóstico por imagem , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
11.
Eur Radiol ; 30(5): 2853-2860, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31953662

RESUMO

OBJECTIVES: To determine if CT texture analysis features are associated with hypovascular pancreas head adenocarcinoma (PHA) postoperative margin status, nodal status, grade, lymphovascular invasion (LVI), and perineural invasion (PNI). METHODS: This Research Ethics Board-approved retrospective cohort study included 131 consecutive patients with resected PHA. Tumors were segmented on preoperative contrast-enhanced CT. Tumor diameter and texture analysis features including mean, minimum and maximum Hounsfield units, standard deviation, skewness, kurtosis, and entropy and gray-level co-occurrence matrix (GLCM) features correlation and dissimilarity were extracted. Two-sample t test and logistic regression were used to compare parameters for prediction of margin status, nodal status, grade, LVI, and PNI. Diagnostic accuracy was assessed using receiver operating characteristic curves and Youden method was used to establish cutpoints. RESULTS: Margin status was associated with GLCM correlation (p = 0.012) and dissimilarity (p = 0.003); nodal status was associated with standard deviation (p = 0.026) and entropy (p = 0.031); grade was associated with kurtosis (p = 0.031); LVI was associated with standard deviation (p = 0.047), entropy (p = 0.026), and GLCM correlation (p = 0.033) and dissimilarity (p = 0.011). No associations were found for PNI (p > 0.05). Logistic regression yielded an area under the curve of 0.70 for nodal disease, 0.70 for LVI, 0.68 for grade, and 0.65 for margin status. Optimal sensitivity/specificity was as follows: nodal disease 73%/72%, LVI 72%/65%, grade 55%/83%, and margin status 63%/66%. CONCLUSIONS: CT texture analysis features demonstrate fair diagnostic accuracy for assessment of hypovascular PHA nodal disease, LVI, grade, and postoperative margin status. Additional research is rapidly needed to identify these high-risk features with better accuracy. KEY POINTS: • CT texture analysis features are associated with pancreas head adenocarcinoma postoperative margin status which may help inform treatment decisions as a negative resection margin is required for cure. • CT texture analysis features are associated with pancreas head adenocarcinoma nodal disease, a poor prognostic feature. • Indicators of more aggressive pancreas head adenocarcinoma biology including tumor grade and LVI can be diagnosed using CT texture analysis with fair accuracy.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/cirurgia , Margens de Excisão , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/cirurgia , Tomografia Computadorizada por Raios X/métodos , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Pâncreas/cirurgia , Neoplasias Pancreáticas/patologia , Prognóstico , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias Pancreáticas
12.
Indian Pediatr ; 56(1): 41-44, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30806360

RESUMO

OBJECTIVE: To describe a novel wrist deformity in b-thalassemia major patients, and their radiographic and magnetic resonance imaging findings. METHODS: 30 patients with b-thalassemia major who were noticed to have ulnar deviation at wrist joint were evaluated for previous history of medications, serum ferritin levels, presence of pain and swelling at the wrist joint, and the duration of iron chelation therapy. Radiographs of wrist and limited magnetic resonance imaging (MRI) sequences were obtained in 30 and 15 patients, respectively. RESULTS: Radiographs revealed varying severity of distal ulnar shortening, distal radial slanting and presence of soft tissue distal to the ulna. MRI showed similar deformities along with abnormal marrow signal at distal ulnar ends; in 8 patients, a soft tissue distal to the distal end of ulna was noted. CONCLUSIONS: Varying severity of radiological abnormalities, predominantly affecting the distal ulna, are present in children and adolescents with b-thalassemia receiving oral chelation therapy.


Assuntos
Terapia por Quelação/efeitos adversos , Quelantes de Ferro/efeitos adversos , Artropatias , Punho , Talassemia beta/tratamento farmacológico , Adolescente , Criança , Feminino , Humanos , Ferro , Quelantes de Ferro/uso terapêutico , Artropatias/induzido quimicamente , Artropatias/diagnóstico por imagem , Artropatias/patologia , Masculino , Ulna/diagnóstico por imagem , Ulna/efeitos dos fármacos , Ulna/patologia , Punho/diagnóstico por imagem , Punho/patologia
13.
J Gerontol A Biol Sci Med Sci ; 72(12): 1703-1709, 2017 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-28329397

RESUMO

BACKGROUND: Resveratrol, a plant-derived polyphenol, has been reported to improve glucose metabolism and vascular function and to extend life span in animal models, but studies in humans have been inconclusive. METHODS: In a randomized, double-blind crossover study, we treated older glucose-intolerant adults (n = 30) with resveratrol (2-3 g/daily) or placebo, each for 6 weeks. A standard mixed-meal test was used to assess insulin sensitivity (Matsuda index) and secretion (C-peptide deconvolution) and vascular function by reactive hyperemia peripheral arterial tonometry. Skeletal muscle samples were obtained for gene expression using RNA-Seq analysis and to assess mitochondrial morphology. RESULTS: There were no changes in glucose tolerance, insulin sensitivity, weight, blood pressure, or lipid profile following resveratrol treatment. Fasting reactive hyperemia index improved with resveratrol (2.02 ± 0.2 vs 1.76 ± 0.02, p = .002). RNA-Seq analysis yielded 140 differentially expressed transcripts (corrected p-value ≤ .05), predominantly associated with mitochondrial genes and noncoding RNA. Ingenuity Pathway Analysis confirmed that mitochondrial dysfunction (p = 2.77 × 10-12) and oxidative phosphorylation (p = 1.41 × 10-11) were the most significantly perturbed pathways. Mitochondrial number, but not size, was increased. CONCLUSIONS: Resveratrol treatment of older adults with impaired glucose regulation may have beneficial effects on vascular function, but not glucose metabolism or insulin sensitivity. Changes in gene expression suggest effects similar to those observed with caloric restriction, which has been shown to increase life and health span in animal models, although its significance for humans is uncertain. Future human studies should address the appropriate dose range and low bioavailability of resveratrol.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Glucose/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Estilbenos/farmacologia , Idoso , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Metabolismo/efeitos dos fármacos , Resveratrol
15.
J Clin Diagn Res ; 10(8): TD01-2, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27656529

RESUMO

Osteochondroma (OC) is a common slow growing tumour of bone. This lesion is frequently seen in the axial skeleton and is relatively uncommon in oral and maxillofacial region. In facial bones, it usually affects the mandibular condyle followed by coronoid process. Very few cases of condylar osteocondroma have been reported in the literature. The aim of this article was to present an atypical case of osteochondroma of bilateral mandibular condyle in an asymptomatic patient and facilitate making an exact diagnosis of it. To the best of our knowledge this is the 2(nd) case of this type reported in literature.

16.
Foot Ankle Surg ; 21(3): e51-4, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26235872

RESUMO

The common cause of posterior ankle impingement syndrome is impingement of the Os trigonum or the posterior talar process. We report a case of a 46-year-old lady having osteochondroma of the posterior talar process, a rare occurrence at this site. This patient was treated with posterior ankle arthroscopic excision through the 2-portal posterior ankle arthroscopy technique in the prone position. 6 months post-operatively, her ankle pain disappeared and ankle range of movement improved significantly and there is no recurrence of the tumour.


Assuntos
Articulação do Tornozelo/cirurgia , Artroscopia/métodos , Neoplasias Ósseas/cirurgia , Osteocondroma/cirurgia , Tálus , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/patologia , Neoplasias Ósseas/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Osteocondroma/diagnóstico , Radiografia
17.
Nat Med ; 14(2): 144-53, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18223655

RESUMO

The proapoptotic BCL-2 family member BAD resides in a glucokinase-containing complex that regulates glucose-driven mitochondrial respiration. Here, we present genetic evidence of a physiologic role for BAD in glucose-stimulated insulin secretion by beta cells. This novel function of BAD is specifically dependent upon the phosphorylation of its BH3 sequence, previously defined as an essential death domain. We highlight the pharmacologic relevance of phosphorylated BAD BH3 by using cell-permeable, hydrocarbon-stapled BAD BH3 helices that target glucokinase, restore glucose-driven mitochondrial respiration and correct the insulin secretory response in Bad-deficient islets. Our studies uncover an alternative target and function for the BAD BH3 domain and emphasize the therapeutic potential of phosphorylated BAD BH3 mimetics in selectively restoring beta cell function. Furthermore, we show that BAD regulates the physiologic adaptation of beta cell mass during high-fat feeding. Our findings provide genetic proof of the bifunctional activities of BAD in both beta cell survival and insulin secretion.


Assuntos
Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Proteína de Morte Celular Associada a bcl/metabolismo , Sequência de Aminoácidos , Animais , Glicemia , Cálcio/metabolismo , Contagem de Células , Sobrevivência Celular/efeitos dos fármacos , Dieta , Glucoquinase/metabolismo , Glucose/farmacologia , Humanos , Hidrocarbonetos/farmacologia , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/enzimologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Modelos Genéticos , Dados de Sequência Molecular , Peptídeos/farmacologia , Fosfosserina/metabolismo , Estrutura Terciária de Proteína , Proteína de Morte Celular Associada a bcl/química , Proteína de Morte Celular Associada a bcl/deficiência
18.
J Clin Invest ; 117(7): 1995-2003, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17571165

RESUMO

Insulin resistance is a major factor in the pathogenesis of type 2 diabetes and is strongly associated with obesity. Increased concentrations of intracellular fatty acid metabolites have been postulated to interfere with insulin signaling by activation of a serine kinase cascade involving PKCtheta in skeletal muscle. Uncoupling protein 3 (UCP3) has been postulated to dissipate the mitochondrial proton gradient and cause metabolic inefficiency. We therefore hypothesized that overexpression of UCP3 in skeletal muscle might protect against fat-induced insulin resistance in muscle by conversion of intramyocellular fat into thermal energy. Wild-type mice fed a high-fat diet were markedly insulin resistant, a result of defects in insulin-stimulated glucose uptake in skeletal muscle and hepatic insulin resistance. Insulin resistance in these tissues was associated with reduced insulin-stimulated insulin receptor substrate 1- (IRS-1-) and IRS-2-associated PI3K activity in muscle and liver, respectively. In contrast, UCP3-overexpressing mice were completely protected against fat-induced defects in insulin signaling and action in these tissues. Furthermore, these changes were associated with a lower membrane-to-cytosolic ratio of diacylglycerol and reduced PKCtheta activity in whole-body fat-matched UCP3 transgenic mice. These results suggest that increasing mitochondrial uncoupling in skeletal muscle may be an excellent therapeutic target for type 2 diabetes mellitus.


Assuntos
Regulação da Expressão Gênica , Resistência à Insulina , Canais Iônicos/metabolismo , Metabolismo dos Lipídeos , Proteínas Mitocondriais/metabolismo , Músculo Esquelético/metabolismo , Proteínas Quinases Ativadas por AMP , Envelhecimento/fisiologia , Animais , Ativação Enzimática , Hormônios/sangue , Humanos , Insulina/sangue , Canais Iônicos/genética , Isoenzimas/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Proteínas Mitocondriais/genética , Complexos Multienzimáticos/metabolismo , Proteína Quinase C/metabolismo , Proteína Quinase C-theta , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Desacopladora 3 , Aumento de Peso
19.
Am J Perinatol ; 23(4): 233-40, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16625501

RESUMO

The objective of this study was to evaluate the incidence of bronchopulmonary dysplasia (BPD), nutritional intake, and growth in premature infants receiving synchronized nasal intermittent positive-pressure ventilation (SNIPPV) versus nasal continuous positive airways pressure (NCPAP) after extubation, at an institution with no prior experience with SNIPPV. This was a retrospective case-control study of infants (born May 2000 to December 2003) at < or = 32 weeks gestation. Extubation to SNIPPV was performed in accordance with a standardized protocol. Infants in the control group were extubated to NCPAP, as per standard nursery practice. There were no significant differences in the maternal characteristics, antenatal corticosteroid use, mode of delivery, gestational age, birthweight, male gender, Apgar scores at 1 and 5 minutes, number of surfactant doses, and duration of endotracheal tube PPV between infants in the control group (n = 30) and those extubated to SNIPPV (n = 30). The duration of NCPAP (median [range]: control versus SNIPPV, 601 [24 to 1270] versus 230.5 [36 to 1200] hours; P < 0.001) and supplemental oxygen (mean +/- standard error of the mean: 84.10 +/- 6.43 versus 63.68 +/- 5.34 days; p = 0.02) was significantly lower in the SNIPPV group. The number of infants with BPD was significantly less in the SNIPPV group (73% versus 40%; p < 0.01). There were no differences between the two groups in total days on parenteral nutrition, caloric intake (total, carbohydrate, protein, or fat), or weight gain. Our results show that introduction of SNIPPV in a neonatal intensive care unit resulted in infants having significantly less need for supplemental oxygen and decreased BPD, without affecting their weight gain or the incidence of other short-term morbidities.


Assuntos
Displasia Broncopulmonar/terapia , Recém-Nascido Prematuro/crescimento & desenvolvimento , Terapia Intensiva Neonatal/métodos , Respiração com Pressão Positiva Intermitente/métodos , Adulto , Displasia Broncopulmonar/epidemiologia , Estudos de Casos e Controles , Doença Crônica , Ingestão de Energia , Feminino , Humanos , Incidência , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Idade Materna , Nariz , Oxigenoterapia , Estudos Retrospectivos , Resultado do Tratamento
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