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1.
Antioxidants (Basel) ; 12(9)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37759966

RESUMO

Chronic hyperglycemia and oxidative stress in Type 2 Diabetes Mellitus trigger cellular dysfunction via the formation of Advanced Glycation End Products (AGEs), resulting in dicarbonyl stress. Glyoxalase-1 (Glo-1) is the main defense against dicarbonyl stress. The aim of this study was to explore any cross-talk between Glo-1 and markers of hyperglycemia and oxidative stress. The siRNA-mediated downregulation of Glo-1 was performed in human microvascular endothelial cell line (HMEC-1). A Glo-1 transgenic rat model was developed. Glo-1 activity, as determined spectrophotometrically, and methylglyoxal were quantified using UPLC-MS/MS and the expression of representative markers of hyperglycemia and oxidative stress was performed using quantitative real-time PCR. A significant increase in the expression of Vascular Cell Adhesion Molecule-1 (VCAM-1) was observed in the case of the siRNA-mediated downregulation of Glo-1 in the microvasculature model under hyperglycemic conditions (p-value < 0.001), as well the as overexpression of Glo-1 in the macrovasculature (p-value = 0.0125). The expression of thioredoxin interacting protein (TXNIP) was found to be significantly upregulated in wildtype diabetic conditions vs. Glo-1 transgenic control conditions (p-value = 0.008), whereas the downregulation of Glo-1 had no impact on TXNIP expression. These findings substantiate the role of VCAM as an important marker of dicarbonyl stress (represented by Glo-1 downregulation), as well as of hyperglycemia, in diabetic vascular complications. Our findings also suggest a potential feedback loop that may exist between Glo-1 and TXNIP, as the highest expression of TXNIP is observed in cases of wildtype diabetic conditions, and the lowest expression of TXNIP is observed when Glo-1 transgene is being expressed in absence of dicarbonyl stress.

2.
CJC Open ; 5(2): 148-157, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36880068

RESUMO

Background: Coronary computed tomographic angiography (CCTA) is preferable to invasive coronary angiography (ICA) for coronary artery disease (CAD) diagnosis in elective patients without known CAD. Methods: We conducted a nonrandomized interventional study involving 2 tertiary care centres in Ontario. From July 2018 to February 2020, outpatients referred for elective ICA were identified through a centralized triage process and were recommended to undergo CCTA first instead of ICA. Patients with borderline or obstructive CAD on CCTA were recommended to undergo subsequent ICA. Intervention acceptability, fidelity, and effectiveness were assessed. Results: A total of 226 patients were screened, with 186 confirmed to be eligible, of whom 166 had patient and physician approval to proceed with CCTA (89% acceptability). Among consenting patients, 156 (94%) underwent CCTA first; 43 (28%) had borderline/obstructive CAD on CCTA, and only 1 with normal/nonobstructive CAD on CCTA was referred for subsequent ICA against protocol (99% fidelity). Overall, 119 of 156 CCTA-first patients did not have ICA within the following 90 days (i.e., 76% potentially avoided ICA, due to the intervention). Among the 36 who underwent ICA post-CCTA per protocol, 24 had obstructive CAD (66.7% diagnostic yield). If all patients who were referred for and underwent ICA at either centre between July 2016 and February 2020 (n = 694 pre-implementation; n = 333 post-implementation) had had CCTA first, an additional 42 patients per 100 would have had an obstructive CAD finding on their ICA (95% confidence interval = 26-59). Conclusion: A centralized triage process, in which elective outpatients referred for ICA are instead referred for CCTA first, appears to be acceptable and effective in diagnosing obstructive CAD and improving efficiencies in our healthcare system.


Contexte: La coronarographie par tomodensitométrie (coro-TDM) est préférable à la coronarographie invasive chez les patients sans coronaropathie connue chez qui le diagnostic d'une coronaropathie n'est pas urgent. Méthodologie: Nous avons réalisé une étude interventionnelle non randomisée dans deux centres de soins tertiaires en Ontario. Les patients ambulatoires pour qui une coronarographie invasive non urgente a été demandée entre juillet 2018 et février 2020 ont été recensés par un processus centralisé de triage et se sont fait recommander de subir d'abord une coro-TDM. Les patients qui présentaient une co-ronaropathie obstructive ou dont les résultats se trouvaient tout juste à la limite de ce diagnostic lors de la coro-TDM se faisaient recommander une coronarographie invasive subséquente. L'acceptabilité de l'intervention, sa fidélité et son efficacité ont été évaluées. Résultats: Au total, 226 patients ont été sélectionnés et 186 ont été jugés admissibles. Parmi ces derniers, 166 ont accepté de subir la coro-TDM recommandée par le médecin (acceptabilité de 89 %). Parmi les patients ayant donné leur consentement, 156 (94 %) se sont d'abord soumis à une coro-TDM, et 43 (28 %) présentaient une coronaropathie obstructive ou des résultats limites selon cet examen. Seulement un patient ne présentant pas de coronaropathie ou présentant une coronaropathie non obstructive à la coro-TDM a été orienté vers une coronarographie invasive subséquente, contrairement au protocole (fidélité de 99 %). En tout, 119 des 156 patients s'étant d'abord soumis à une coro-TDM n'ont pas eu à subir une coronarographie invasive dans les 90 jours suivants (76 % d'entre eux ont potentiellement évité une coronarographie invasive grâce à cette première intervention). Parmi les 36 patients qui ont subi une coronarographie invasive après la coro-TDM, comme le recommandait le protocole, 24 présentaient une coronaropathie obstructive (rendement diagnostique de 66,7 %). Si tous les patients qui ont été orientés vers une coronarographie invasive et qui se sont soumis à cet examen dans l'un ou l'autre des centres entre juillet 2016 et février 2020 (n = 694 avant l'instauration; n = 333 après l'instauration) avaient d'abord passé une coro-TDM, une coronaropathie obstructive aurait été décelée lors de la coronarographie invasive chez 42 patients de plus par tranche de 100 patients (intervalle de confiance à 95 % : 26 à 59). Conclusion: Le recours à un processus de triage centralisé permettant de faire d'abord passer une coro-TDM aux patients ambulatoires dans une situation non urgente qui doivent subir une coronarographie invasive semble être un moyen acceptable et efficace de diagnostiquer la coronaropathie obstructive et d'améliorer l'efficacité dans notre système de santé.

3.
J Biomol Struct Dyn ; 41(23): 13707-13717, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36812296

RESUMO

Glyoxalase-1 (Glo-1) is a key member of the Glyoxalase system, the primary line of defense against dicarbonyl stress which, in tandem, with reduced levels of expression or activity of Glyoxalase-1 enzyme, has been implicated in various human diseases like type 2 diabetes mellitus (T2DM) and its vascular complications. The association of Glo-1 single nucleotide polymorphisms with genetic susceptibility to T2DM and its vascular complications is yet to be explored. Therefore, in this study, we have employed a computational approach to identify the most damaging missense or nonsynonymous SNPs (nsSNPs) in Glo-1 gene. Initially, we characterized missense SNPs that are damaging to the structural and functional integrity of Glo-1 using various bioinformatic tools. These tools included SIFT, PolyPhen-2, SNAP, PANTHER, PROVEAN, PhD-SNP, SNPs&GO, I-Mutant, MUpro and MutPred2. One of these missense SNPs (rs1038747749; corresponding to amino acid change Arginine to Glutamine at position 38) was found to be highly conserved in evolution and is an important part of the enzyme's active site, glutathione binding site, as well as the dimeric interface based on the results obtained from ConSurf and NCBI Conserved Domain Search tools. Project HOPE reported that this mutation replaces a positively charged polar amino acid (Arginine) with a small, neutrally charged amino acid (Glutamine). Comparative modelling of wildtype and mutant (R38Q) Glo-1 proteins was performed in the run up to molecular dynamics simulation analysis which showed that rs1038747749 adversely impacts Glo-1 protein's stability, rigidity, compactness, hydrogen bonds/interactions as demonstrated by the results of various parameters computed during the analysis.Communicated by Ramaswamy H. Sarma.


Assuntos
Diabetes Mellitus Tipo 2 , Simulação de Dinâmica Molecular , Humanos , Polimorfismo de Nucleotídeo Único , Glutamina/genética , Aminoácidos/genética , Biologia Computacional/métodos , Arginina
4.
Curr Cancer Drug Targets ; 23(3): 222-234, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36154575

RESUMO

OBJECTIVE: Human breast cancer is among one major health concerns with high prevalence and mortality among women worldwide. Various cellular signaling pathways are implicated in carcinogenesis. One of the major pathways that affect the downstream cellular growth cascades is Mevalonate pathway (MVA). The inhibition of MVA is therapeutically beneficial for various cancers. Pamidronate (PAM) (MVA inhibitor), a nitrogen-containing bisphosphosphonate, is an antiresorptive FDAapproved drug. The objective of our study was to explore adjuvant therapy using a combination of PAM and an alkylating agent, Temozolomide (TMZ) against breast cancer. METHODS: We have examined the differential gene and protein expression in response to the combination treatment strategy. For gene expression analysis RT-qPCR and for proteomic study, twodimensional gel electrophoresis and mass spectrometry techniques were utilized. RESULTS: Combination treatment (PAM+TMZ) showed more pronounced cytotoxic effect as compared to single agent treatment. Our results indicate that MVA pathway regulatory genes (FDFT1, FDPS, KRAS) are significantly (p<0.05) downregulated in combination-treated breast cancer cells. The differential proteomic analysis showed lower expression of GFAP, PPA1 and TRIM68 proteins after synergistic treatment whereas, these proteins are found to be up-regulated in multiple cancers. CONCLUSION: The present study reveals that a combination of PAM and TMZ produces an effective anti-cancerous effect on breast cancer cells. Therefore, this novel therapeutic regimen is likely to provide a better treatment strategy for breast cancer.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Temozolomida/farmacologia , Pamidronato , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Proteômica , Linhagem Celular Tumoral , Proteínas com Motivo Tripartido , Autoantígenos , Ubiquitina-Proteína Ligases
5.
J Recept Signal Transduct Res ; 36(3): 310-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26523375

RESUMO

Wnt signaling pathway plays an important role in cell renewal, tumorigenesis, organogenesis, bone formation and bone resorption. Wnt signaling pathway is divided into two outlets: Wnt-ß-catenin pathway (canonical pathway) and Wnt-calcium pathway (non-canonical pathway). miRNAs play a key role in the regulation of Wnt signaling pathway. In this review, we highlight the basic indulgent of miRNAs-mediated regulation of Wnt signaling pathway. We focus on the role of miRNAs at different levels of Wnt signaling: signaling molecules, their associated signaling proteins, regulatory proteins, transcription factors and related cytokines. Finally, we concluded that these multiple levels of targeting may have diagnostic potential as well as therapeutic prospective in future treatment.


Assuntos
Doença/genética , Redes Reguladoras de Genes , MicroRNAs/genética , Via de Sinalização Wnt/genética , Animais , Citocinas/metabolismo , Humanos , MicroRNAs/metabolismo , Fatores de Transcrição/metabolismo
6.
Emerg Radiol ; 19(4): 317-22, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22419058

RESUMO

Mineral foreign bodies (stones) are infrequent findings in clinical and radiological practice. However, a growing number of reports indicate that they raise clinical and diagnostic concern in ophthalmology, neurosurgery, maxillofacial surgery, otolaryngology, gastroenterology, and vascular surgery. Dense finding in the soft tissue without clear history of foreign body penetration may represent diagnostic challenge mimicking calcifications or bony fragments. The aim of this work is to analyze the appearance of stone foreign bodies on radiographs and computed tomography. A collection of minerals and rocks was used for analysis. The clinical case of a stony foreign body which penetrated into the soft tissue of the leg is used to demonstrate the diagnostic challenge and management. Available literature describing imaging characteristics of stones was reviewed. The results of this work will help in diagnostic interpretation and assessment of stone foreign body composition.


Assuntos
Corpos Estranhos/diagnóstico por imagem , Traumatismos do Joelho/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Acidentes por Quedas , Adolescente , Diagnóstico Diferencial , Corpos Estranhos/cirurgia , Humanos , Traumatismos do Joelho/cirurgia , Masculino , Ultrassonografia de Intervenção
7.
Healthc Q ; 12 Spec No Patient: 15-22, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19667773

RESUMO

The use of computed tomography (CT) is growing, and, consequently, the associated radiation dose to patients is increasing as well. There is also increasing evidence linking the radiation dose within the range of diagnostic CT with a significantly increased risk of malignancy. These two factors combine to make radiation dose from diagnostic CT a public health concern. In order to practise to the best of our abilities and avoid harming patients, the radiation dose from CT must be minimized. Administrators, technologists, radiologists and other physicians are encouraged to work toward this goal through the use of education and a multi-faceted team approach. The objective of this paper is to educate healthcare professionals about the radiation dose from diagnostic CT, including utilization rates, typical examination doses and the risks of this radiation. Our experience in Saskatchewan is discussed. Suggestions regarding CT dose management and optimization are highlighted.


Assuntos
Administradores Hospitalares/educação , Doses de Radiação , Tomografia Computadorizada por Raios X , Canadá , Humanos , Neoplasias/etiologia , Medição de Risco
8.
Can Assoc Radiol J ; 60(2): 71-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19433037

RESUMO

OBJECTIVE: To calculate the effective dose from diagnostic computed tomography (CT) scans in Saskatchewan, Canada, and compare with other reported dose levels. METHODS: Data from CT scans were collected from 12 scanners in 7 cities across Saskatchewan. The patient age, scan type, and selected technique parameters including the dose length product and the volume computed tomography dose index were collected for a 2-week period. This information then was used to calculate effective doses patients are exposed to during CT examinations. Data from 2,061 clinically indicated CT examinations were collected, and of them 1,690 were eligible for analysis. Every examination during a 2-week period was recorded without selection. RESULTS: The average provincial estimated patient dose was as follows: head, 2.7 mSv (638 scans; standard deviation [SD], +/-1.6); chest, 11.3 mSv (376 scans; SD, +/-8.9); abdomen-pelvis, 15.5 mSv (578 scans; SD, +/-10.0); abdomen, 11.7 mSv (80 scans; SD, +/-11.48), and pelvis, 8.6 mSv (18 scans; SD, +/-6.04). Significant variation in dose between the CT scanners was observed (P = .049 for head, P = .001 for chest, and P = .034 for abdomen-pelvis). CONCLUSIONS: Overall, the estimated dose from diagnostic CT examinations was similar to other previously published Canadian data from British Columbia. This dose varied slightly from some other published standards, including being higher than those found in a review conducted in the United Kingdom in 2003.


Assuntos
Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Cabeça/diagnóstico por imagem , Humanos , Lactente , Recém-Nascido , Pulmão/diagnóstico por imagem , Pessoa de Meia-Idade , Pelve/diagnóstico por imagem , Radiografia Abdominal/métodos , Radiografia Abdominal/estatística & dados numéricos , Saskatchewan , Adulto Jovem
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