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1.
Curr Oncol ; 31(3): 1562-1571, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38534952

RESUMO

Background: The effect of COVID-19 on treatment outcomes in the literature remains limited and is mostly reported either as predictive survival using prioritization and modeling techniques. We aimed to quantify the effect of COVID-19 on lung cancer survival using real-world data collected at the Jewish General Hospital, Montreal. Methods: This is a retrospective chart review study of patients diagnosed between March 2019 and March 2022. We compared three cohorts: pre-COVID-19, and 1st and 2nd year of the pandemic. Results: 417 patients were diagnosed and treated with lung cancer at our centre: 130 in 2019, 103 in 2020 and 184 in 2021. Although the proportion of advanced/metastatic-stage lung cancer remained the same, there was a significant increase in the late-stage presentation during the pandemic. The proportion of M1c (multiple extrathoracic sites) cases in 2020 and 2021 was 57% and 51%, respectively, compared to 31% in 2019 (p < 0.05). Median survival for early stages of lung cancer was similar in the three cohorts. However, patients diagnosed in the M1c stage had a significantly increased risk of death. The 6-month mortality rate was 53% in 2021 compared to 47% in 2020 and 29% in 2019 (p = 0.004). The median survival in this subgroup of patients decreased significantly from 13 months in 2019 to 6 months in 2020 and 5 months in 2021 (p < 0.001). Conclusions: This study is, to our knowledge, the largest single-institution study in Canada looking at lung cancer survival during the COVID-19 pandemic. Our study looks at overall survival in the advanced/metastatic setting of NSCLC during the COVID-19 pandemic. We have previously reported on treatment pattern changes and increased wait times for NSCLC patients during the pandemic. In this study, we report that the advanced/metastatic subgroup had both an increase in the 6-month mortality rate and worsening overall survival during this same time period. Although there was no statistical difference in the proportion of patients with advanced disease, there was a concerning trend of increased M1c disease in cohorts 2 and 3. The higher M1c disease during the COVID-19 pandemic (cohorts 2 and 3) likely played a crucial role in increasing the 6-month mortality rate and leading to a reduced overall survival of lung cancer patients during the pandemic. These findings are more likely to be better identified with longer follow-up.


Assuntos
COVID-19 , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Pandemias , Estudos Retrospectivos , Canadá , Carcinoma Pulmonar de Células não Pequenas/patologia
2.
Curr Oncol ; 29(11): 8677-8685, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36421337

RESUMO

BACKGROUND: We have recently reported a 35% drop in new lung cancer diagnoses and a 64% drop in lung cancer surgeries during the first year of the pandemic. METHODS: The target population was divided into three cohorts: pre-COVID-19 (2019), first year of COVID-19 (2020), and second year of COVID-19 (2021). RESULTS: The number of new lung cancer diagnoses during the second year of the pandemic increased by 75%, with more than 50% being in the advanced/metastatic stage. There was a significant increase in cases with multiple extrathoracic sites of metastases during the pandemic. During the first year of the pandemic, significantly more patients were treated with radiosurgery compared to the pre-COVID-19 year. During the second year, the number of radiosurgery and surgical cases returned to pre-COVID-19 levels. No significant changes were observed in systemic chemotherapy and targeted therapy. No statistical difference was identified in the mean wait time for diagnosis and treatment during the three years of observation. However, the wait time for surgery was prolonged compared to the pre-COVID-19 cohort. CONCLUSIONS: The significant drop in new diagnoses of lung cancer during the first year of the pandemic was followed by an almost two-fold increase in the second year, with the increased rate of metastatic disease with multiple extra-thoracic site metastases. Limited access to surgery resulted in the more frequent use of radiosurgery.


Assuntos
COVID-19 , Neoplasias Pulmonares , Radiocirurgia , Humanos , Canadá/epidemiologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patologia , Terapia Combinada
3.
Curr Oncol ; 29(2): 1107-1116, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-35200593

RESUMO

BACKGROUND: Recent studies have demonstrated the utility of cell-free tumor DNA (ctDNA) from plasma as an alternative source of genomic material for detection of sensitizing and resistance mutations in NSCLC. We hypothesized that the plasma level of ctDNA is an effective biomarker to provide a non-invasive and thus a less risky method to determine new resistance mutations and to monitor response to treatment and tumor progression in lung cancer patients. METHODS: This prospective cohort study was approved and conducted at the Peter Brojde Lung Cancer Centre, Montreal. Blood was collected in STRECK tubes at four time points. DNA was extracted from plasma, and ctDNA was analyzed for the presence of mutations in the EGFR gene using the COBAS® EGFR v2 qPCR (Roche) test. RESULTS: Overall, 75 pts were enrolled in the study. In total, 23 pts were TKI-naïve, and 52 were already receiving first-line TKI treatment. ctDNA detected the original mutations (OM) in 35/75 (48%) patients. Significantly higher detection rates were observed in TKI-naïve patients compared to the TKI-treated group, 70% versus 37%, respectively (p = 0.012). The detection of the original mutation at the study baseline was a negative predictor of progression-free survival (PFS) and overall survival (OS). The resistance mutation (T790M) was detected in 32/74 (43%) patients. In 27/32 (84%), the T790M was detected during treatment with TKI: in 25/27 patients, T790M was detected at the time of radiologic progression, in one patient, T790M was detected before radiologic progression, and in one patient, T790M was detected four weeks after starting systemic chemotherapy post progression on TKI. At the time of progression, the detection of T790M significantly correlates with the re-appearance of OM (p = 0.001). CONCLUSION: Plasma ctDNA is a noninvasive patient-friendly test that can be used to monitor response to treatment, early progression, and detection of acquired resistant mutations. Monitoring of clearance and re-emergence of driver mutations during TKI treatment effectively identifies progression of the disease. As larger NGS panels are available for ctDNA testing, these findings may also have implications for other biomarkers. The results from ongoing and prospective studies will further determine the utility of plasma testing to diagnose, monitor for disease progression, and guide treatment decisions in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , DNA Tumoral Circulante , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , DNA Tumoral Circulante/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Estudos Prospectivos , Inibidores de Proteínas Quinases/uso terapêutico
4.
Curr Oncol ; 28(6): 5179-5191, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34940073

RESUMO

The discovery of EGFR tyrosine kinase inhibitors (TKI) for the treatment of EGFR mutant (EGFRm) metastatic NSCLC is regarded as a landmark in lung cancer. EGFR-TKIs have now become a standard first-line treatment for EGFRm NSCLC. The aim of this retrospective cohort study is to describe real-world patterns of treatment and treatment outcomes in patients with EGFRm metastatic NSCLC who received EGFR-TKI therapy outside of clinical trials. One hundred and seventy EGFRm metastatic NSCLC patients were diagnosed and initiated on first-line TKI therapy between 2004 and 2018 at the Peter Brojde Lung Cancer Centre in Montreal. Following progression of the disease, 137 (80%) patients discontinued first-line treatment. Moreover, 80/137 (58%) patients received second-line treatment, which included: EGFR-TKIs, platinum-based, or single-agent chemotherapy. At the time of progression on first-line treatment, 73 patients were tested for the T790M mutation. Moreover, 30/73 (41%) patients were found to be positive for the T790M mutation; 62/80 patients progressed to second-line treatment and 20/62 were started on third-line treatment. The median duration of treatment was 11.5 (95% CI; 9.62-13.44) months for first-line treatment, and 4.4 (95% CI: 1.47-7.39) months for second-line treatment. Median OS from the time of diagnosis of metastatic disease was 23.5 months (95% CI: 16.9-30.1) and median OS from the initiation of EGFR-TKI was 20.6 months (95% CI: 13.5-27.6). We identified that ECOG PS ≤ 2, presence of exon 19 deletion mutation, and absence of brain metastases were associated with better OS. A significant OS benefit was observed in patients treated with osimertinib in second-line treatment compared to those who never received osimertinib. Overall, our retrospective observational study suggests that treatment outcomes in EGFRm NSCLC in real-world practice, such as OS and PFS, reflect the result of RCTs. However, given the few observational studies on real-world treatment patterns of EGFR-mutant NSCLC, this study is important for understanding the potential impact of EGFR-TKIs on survival outside of clinical trials. Further real-world studies are needed to characterize patient outcomes for emerging therapies, including first-line osimertinib use and combination of osimertinib with chemotherapy and potential future combination of osimertinib and novel anticancer drug, outside of a clinical trial setting.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Quebeque , Estudos Retrospectivos
5.
Nat Chem ; 12(3): 276-283, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32042137

RESUMO

Anti-Markovnikov additions to alkenes have been a longstanding goal of catalysis, and anti-Markovnikov addition of arenes to alkenes would produce alkylarenes that are distinct from those formed by acid-catalysed processes. Existing hydroarylations are either directed or occur with low reactivity and low regioselectivity for the n-alkylarene. Herein, we report the first undirected hydroarylation of unactivated alkenes with unactivated arenes that occurs with high regioselectivity for the anti-Markovnikov product. The reaction occurs with a nickel catalyst ligated by a highly sterically hindered N-heterocyclic carbene. Catalytically relevant arene- and alkene-bound nickel complexes have been characterized, and the rate-limiting step was shown to be reductive elimination to form the C-C bond. Density functional theory calculations, combined with second-generation absolutely localized molecular orbital energy decomposition analysis, suggest that the difference in activity between catalysts containing large and small carbenes results more from stabilizing intramolecular non-covalent interactions in the secondary coordination sphere than from steric hindrance.


Assuntos
Alcenos/química , Complexos de Coordenação/química , Hidrocarbonetos Aromáticos/química , Níquel/química , Alquilação , Catálise , Temperatura Alta , Metano/análogos & derivados , Metano/química , Estrutura Molecular , Oxirredução , Estereoisomerismo , Termodinâmica
6.
J Obstet Gynaecol Can ; 42(5): 591-600, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31818693

RESUMO

OBJECTIVE: This study sought to describe the incidence inadequate prenatal care (IPNC) at an urban level II hospital in Hamilton, Ontario, and to compare the characteristics and outcomes of mothers who received IPNC and their newborns with those who received adequate prenatal care (APNC). This study is the first part of a mixed-methods research program aimed at informing the development of an interdisciplinary, patient-centred, prenatal care program for people who struggle to access conventional modes of care. METHODS: This retrospective cohort study compared mothers and neonates born at St. Joseph's Health Care Hamilton in 2016 with IPNC (fewer than or equal to four antenatal visits, or first visit in third trimester) with those born with APNC (five or more prenatal visits and initial visit before the third trimester). Cases and controls matched 3:1 for age and parity were identified through a retrospective chart review. RESULTS: In total 3235 charts were reviewed, and 69 cases of IPNC were identified (2.1%). The IPNC group had lower education and higher unemployment levels, as well as higher rates of smoking and drug use. Our primary and secondary outcomes of newborn custody loss, neonatal intensive care unit admission, and neonatal length of stay were significantly higher in the IPNC group. CONCLUSION: Patients delivering with IPNC represent a high-risk group with increased rates of adverse neonatal outcomes and newborn custody loss. This quantitative study will inform future research and innovative interdisciplinary program development aimed at increasing access to prenatal care in an effort to improve maternal and neonatal outcomes.


Assuntos
Complicações na Gravidez , Cuidado Pré-Natal/estatística & dados numéricos , Determinantes Sociais da Saúde , Desemprego/estatística & dados numéricos , Adolescente , Adulto , Custódia da Criança , Feminino , Humanos , Incidência , Recém-Nascido , Pessoa de Meia-Idade , Ontário/epidemiologia , Paridade , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , População Urbana , Adulto Jovem
7.
Nat Commun ; 10(1): 5647, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31827103

RESUMO

Intravital microscopy is a powerful technique to observe dynamic processes with single-cell resolution in live animals. No intravital window has been developed for imaging the colon due to its anatomic location and motility, although the colon is a key organ where the majority of microbiota reside and common diseases such as inflammatory bowel disease, functional gastrointestinal disorders, and colon cancer occur. Here we describe an intravital murine colonic window with a stabilizing ferromagnetic scaffold for chronic imaging, minimizing motion artifacts while maximizing long-term survival by preventing colonic obstruction. Using this setup, we image fluorescently-labeled stem cells, bacteria, and immune cells in live animal colons. Furthermore, we image nerve activity via calcium imaging in real time to demonstrate that electrical sacral nerve stimulation can activate colonic enteric neurons. The simple implantable apparatus enables visualization of live processes in the colon, which will open the window to a broad range of studies.


Assuntos
Colo/diagnóstico por imagem , Microscopia Intravital/métodos , Imagem Óptica/métodos , Animais , Movimento Celular , Colo/microbiologia , Corantes Fluorescentes/química , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco/química , Células-Tronco/citologia
8.
J Chem Phys ; 149(14): 144103, 2018 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-30316269

RESUMO

Coupled cluster valence bond (CCVB) is a simple electronic structure method based on a perfect pairing (PP) reference with 2-pair recouplings for strong electron correlation problems. CCVB is spin-pure, size-consistent, and can exactly (in its active space) separate any molecule into atoms for which unrestricted Hartree-Fock (UHF) at dissociation is the sum of the ground state UHF energies of the atoms. However CCVB is far from a complete description of strong correlations. Its first failure to exactly describe spin-recouplings arises at the level of 3 electron pairs, such as the recoupling of 3 triplet oxygen atoms in the dissociation of singlet ozone. Such situations are often associated with spin frustration. To address this limitation, an extension of CCVB, termed CCVB+i3, is reported here that includes an independent (i) amplitude approximation to the 3-pair recouplings. CCVB+i3 thereby has the same basic computational requirements as those of CCVB, which has previously been shown to be an efficient method. CCVB+i3 correctly separates molecules that CCVB cannot. As a by-product, an independent 2-pair amplitude approximation to CCVB, called PP+i2, is also defined. Remarkably, PP+i2 can also correctly separate systems that CCVB cannot. CCVB+i3 is validated on the symmetric dissociation of D3h ozone. CCVB+i3 is then used to explore the role of 3-pair recouplings in an [Fe4S4(SCH3)4]2- cluster that has been used to model the iron-sulfur core of [Fe4S4] ferredoxins. Using localized PP orbitals, such recouplings are demonstrated to be large in some low-lying singlet excited states of the cluster. Significant 3 pair recoupling amplitudes include the usual triangular motif associated with spin frustration and other geometric arrangements of the 3 entangled pairs across the 4 iron centers.

9.
J Integr Med ; 16(6): 390-395, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30292672

RESUMO

OBJECTIVE: Increasing numbers of cancer patients are using Chinese herbs (CHs). However, differences among prior studies make it difficult to draw firm conclusions about the clinical usefulness of any specific CH formula. The primary objective of this study was to establish the acceptability of taking a standardized CH formula for patients with advanced lung cancer. The secondary objective was to identify any toxicities attributable to this CH formula and to measure changes in quality of life. METHODS: A single-arm, prospective study of a 6-week intervention with a selected CH formula in 15 patients with stage 4 nonsmall-cell lung cancer (NSCLC, Seventh American Joint Committee on Cancer TNM staging system). RESULTS: Patients with advanced lung cancer were interested in using the CH formula. Completion (93%) and adherence (98%) levels were very high and most patients perceived the CH treatment as easy to take and were willing to take the CHs used in the study again if it was available. About half of the patients reported adverse events, all of which were mild (Grade 1 or 2) and only a small minority (8%) were potentially related to CHs. No biochemical or hematological evidence of toxicity was observed. Overall, there were improvement in quality of life, and reduced feelings of tiredness and sleepiness. CONCLUSION: This study provides preliminary evidence that short-term use of a carefully selected and prepared CH formula in patients with stage 4 NSCLC is acceptable and safe.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Composição de Medicamentos/normas , Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/química , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida
10.
Pathology ; 50(5): 511-518, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29935727

RESUMO

Better characterisation and understanding of renal cell carcinoma (RCC) development and progression lead to better diagnosis and clinical outcomes. In this study, expression of nuclear factor-kappa B (NF-κB) subunits: p65 (RelA), p105/p50, p100/p52, and cRel in RCC tissue were compared with corresponding normal kidney, along with tumour characteristics and survival outcome. Ninety-six cases of RCC with paired normal kidney were analysed. Clinicopathological data, demographics and survival data were available. Immunohistochemistry (IHC) for NF-κB subtypes was analysed using the Aperio digital pathology system for overall cellular expression and localisation. The prognostic cancer-specific survival value of the subunits in RCC patients was analysed. Approximately 50% of patients had clinical stage T1, with 22 patients having metastases at presentation. RCC subtypes were: clear cell (n = 76); papillary (n = 11); chromophobe (n = 5); clear cell tubulopapillary (n = 3); and one multilocular cystic RCC. Median follow up was 54.5 months (0.2-135), with 28 deaths at time of analysis. NF-κB p65 had higher overall and nuclear expressions, with lower overall and nuclear expressions of p50, p52 and cRel in RCC compared with normal kidney. Higher expressions of p65 (nuclear), p52 (overall and nuclear) and p50 (overall) correlated significantly with worse cancer-specific survival. This is the first large series of analysis of expression of NF-κB subunits in RCC. Especially with regards to the less studied subunits (p52, p50, cRel), our results allow a better understanding the role of NF-κB in RCC development and progression, and may pave the way for future targeted NF-κB subunit specific therapies.


Assuntos
Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/mortalidade , Neoplasias Renais/metabolismo , NF-kappa B/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/diagnóstico , Núcleo Celular/metabolismo , Feminino , Humanos , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Transdução de Sinais/fisiologia , Análise Serial de Tecidos/métodos
11.
Anticancer Drugs ; 29(8): 817-819, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29889673

RESUMO

Immune checkpoint inhibitors have revolutionized cancer therapy. Given their mechanism of action, immune-related adverse events have been associated with their use. We present the first documented case of pembrolizumab-induced grade IV neutropenia. A 73-year-old women known for myositis, Crohn's disease, and hypothyroidism and diagnosed with PD-L1 positive stage IV pulmonary adenocarcinoma is treated with Pembrolizumab. She develops grade IV neutropenia 2 weeks after her second infusion. She is therefore hospitalized and treated initially with corticosteroids, granulocyte colony-stimulating factor, and intravenous immunoglobulins. Given the persistent neutropenia, cyclosporine was added, but quickly stopped owing to fever. The patient recovered her neutrophils 6.5 weeks after her initial Pembrolizumab infusion and 12 days after admission. She has been subsequently successfully tapered off steroids with no recurrence after 3 months of follow-up. This is the first case of grade IV neutropenia secondary to Pembrolizumab. This case is of particular interest given the patient's pre-existing autoimmune history. Treatment of severe neutropenia due to other PD1 inhibitors has generally consisted of steroids, granulocyte colony-stimulating factor, intravenous immunoglobulins, mycophenolate mofetil, cyclosporine A, and anti-thymocyte globulins - though the benefits of immunosuppression are not clear and may be harmful given the infectious risks. Large studies are required to clarify the spectrum and optimal management of immune-related adverse events and overall risk/benefits of immune checkpoint inhibitors in patients with pre-existing autoimmunity.


Assuntos
Adenocarcinoma de Pulmão/sangue , Adenocarcinoma de Pulmão/tratamento farmacológico , Anticorpos Monoclonais Humanizados/efeitos adversos , Neutropenia/induzido quimicamente , Idoso , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/efeitos adversos , Antineoplásicos Imunológicos/uso terapêutico , Feminino , Humanos , Neutropenia/tratamento farmacológico
12.
Toxicol Pathol ; 46(4): 449-459, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29683083

RESUMO

Indoxyl sulfate (IS) is a protein-bound uremic toxin that accumulates in patients with declining kidney function. Although generally thought of as a consequence of declining kidney function, emerging evidence demonstrates direct cytotoxic role of IS on endothelial cells and cardiomyocytes, largely through the expression of pro-inflammatory and pro-fibrotic factors. The direct toxicity of IS on human kidney proximal tubular epithelial cells (PTECs) remains a matter of debate. The current study explored the effect of IS on primary cultures of human PTECs and HK-2, an immortalized human PTEC line. Pathologically relevant concentrations of IS induced apoptosis and increased the expression of the proapoptotic molecule Bax in both cell types. IS impaired mitochondrial metabolic activity and induced cellular hypertrophy. Furthermore, statistically significant upregulation of pro-fibrotic (transforming growth factor-ß, fibronectin) and pro-inflammatory molecules (interleukin-6, interleukin-8, and tumor necrosis factor-α) in response to IS was observed. Albumin had no influence on the toxicity of IS. The results of this study suggest that IS directly induced a pro-inflammatory and pro-fibrotic phenotype in proximal tubular cells. In light of the associated apoptosis, hypertrophy, and metabolic dysfunction, this study demonstrates that IS may play a role in the progression of chronic kidney disease.


Assuntos
Apoptose/efeitos dos fármacos , Indicã/toxicidade , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/patologia , Células Cultivadas , Humanos , Hipertrofia/patologia
14.
Am J Physiol Renal Physiol ; 314(5): F956-F968, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29357409

RESUMO

Oxidative stress and mitochondrial dysfunction exacerbate acute kidney injury (AKI), but their role in any associated progress to chronic kidney disease (CKD) remains unclear. Antioxidant therapies often benefit AKI, but their benefits in CKD are controversial since clinical and preclinical investigations often conflict. Here we examined the influence of the antioxidant N-acetyl-cysteine (NAC) on oxidative stress and mitochondrial function during AKI (20-min bilateral renal ischemia plus reperfusion/IR) and progression to chronic kidney pathologies in mice. NAC (5% in diet) was given to mice 7 days prior and up to 21 days post-IR (21d-IR). NAC treatment resulted in the following: prevented proximal tubular epithelial cell apoptosis at early IR (40-min postischemia), yet enhanced interstitial cell proliferation at 21d-IR; increased transforming growth factor-ß1 expression independent of IR time; and significantly dampened nuclear factor-like 2-initiated cytoprotective signaling at early IR. In the long term, NAC enhanced cellular metabolic impairment demonstrated by increased peroxisome proliferator activator-γ serine-112 phosphorylation at 21d-IR. Intravital multiphoton microscopy revealed increased endogenous fluorescence of nicotinamide adenine dinucleotide (NADH) in cortical tubular epithelial cells during ischemia, and at 21d-IR that was not attenuated with NAC. Fluorescence lifetime imaging microscopy demonstrated persistent metabolic impairment by increased free/bound NADH in the cortex at 21d-IR that was enhanced by NAC. Increased mitochondrial dysfunction in remnant tubular cells was demonstrated at 21d-IR by tetramethylrhodamine methyl ester fluorimetry. In summary, NAC enhanced progression to CKD following AKI not only by dampening endogenous cellular antioxidant responses at time of injury but also by enhancing persistent kidney mitochondrial and metabolic dysfunction.


Assuntos
Acetilcisteína/toxicidade , Injúria Renal Aguda/complicações , Antioxidantes/toxicidade , Rim/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Insuficiência Renal Crônica/induzido quimicamente , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Injúria Renal Aguda/fisiopatologia , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Progressão da Doença , Metabolismo Energético/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Rim/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência por Excitação Multifotônica , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , NAD/metabolismo , PPAR gama/metabolismo , Fosforilação , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/patologia , Insuficiência Renal Crônica/fisiopatologia , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Fator de Crescimento Transformador beta1/metabolismo
15.
Clin Pharmacokinet ; 57(2): 243-254, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28578536

RESUMO

BACKGROUND AND OBJECTIVE: Prasugrel, a P2Y12 adenosine diphosphate (ADP) receptor antagonist, inhibits ADP-mediated platelet activation and aggregation in patients with sickle cell anemia (SCA). We developed a population pharmacokinetic (popPK) model in pediatric patients from 2 to <18 years of age with SCA, and performed exposure-response evaluations to characterize the effects of prasugrel in a subset of these patients who weighed 19 kg or more and experienced at least two episodes of vaso-occlusive crises (VOC) in the past year. METHODS: A three-compartment popPK model adapted from that used in adults with acute coronary syndrome was used to describe the relationship between plasma concentrations of prasugrel's active metabolite (Pras-AM) and time using data from phase II and III clinical studies in children. A VOC event rate model was developed from the phase III study to explore the exposure-response relationship between Pras-AM exposure and VOC, and included evaluation of covariates. RESULTS: The final popPK model for children with SCA provided a reasonable fit to Pras-AM plasma concentrations over time, with estimates of apparent clearance (CL/F) (172 L/h) and apparent volume of distribution (Vd/F) (51.7 L) that were comparable to previous studies in adults. The final model included weight as a covariate on both CL/F and Vd/F, and age as a covariate on CL/F. Analyses of safety (bleeding events requiring medical intervention) and efficacy (VOC event rate) variables showed no apparent relationship to model-predicted Pras-AM exposure quartiles, and no statistically significant effects of intrinsic or extrinsic factors on the VOC event rate were identified in the VOC event rate model. The effect of post hoc exposures on the VOC event rate did not reach statistical significance. CONCLUSIONS: A popPK model was developed that provided reasonable parameter estimates, goodness-of-fit diagnostics, and visual predictive checks when applied to Pras-AM plasma concentrations in pediatric patients with SCA. Post hoc exposures obtained from this model did not correlate with measures of VOC or bleeding events in this population.


Assuntos
Anemia Falciforme/tratamento farmacológico , Modelos Biológicos , Inibidores da Agregação Plaquetária/administração & dosagem , Cloridrato de Prasugrel/administração & dosagem , Adolescente , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Masculino , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/farmacocinética , Cloridrato de Prasugrel/efeitos adversos , Cloridrato de Prasugrel/farmacocinética , Ensaios Clínicos Controlados Aleatórios como Assunto
16.
Am J Cardiovasc Drugs ; 17(2): 109-121, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27854064

RESUMO

Prasugrel is a third-generation thienopyridine platelet P2Y12 adenosine diphosphate (ADP) receptor antagonist administered with aspirin for the treatment of patients with acute coronary syndrome (ACS) with planned percutaneous coronary intervention. Prasugrel is administered periprocedurally at an oral loading dose of 60 mg followed by daily maintenance doses (MDs) of 10 mg for most patients and 5 mg for patients weighing <60 kg or aged ≥75 years. Data from a prasugrel phase III study, TRITON-TIMI 38, suggested that a lower MD might be more suitable for patients weighing <60 kg or aged ≥75 years; subsequent pharmacokinetic and pharmacodynamic studies have indicated that prasugrel 5 mg reduced platelet reactivity in these populations to an extent similar to that of prasugrel 10 mg in heavier or younger patients. Clinical experience with prasugrel 5 mg is limited, and additional studies are needed to verify the clinical efficacy and safety of this dose in these challenging populations.


Assuntos
Intervenção Coronária Percutânea/métodos , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico , Cloridrato de Prasugrel/farmacologia , Cloridrato de Prasugrel/uso terapêutico , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Receptores Purinérgicos P2Y12/efeitos dos fármacos , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/cirurgia , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Cloridrato de Prasugrel/efeitos adversos , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos
17.
Thromb Haemost ; 117(3): 580-588, 2017 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-27929203

RESUMO

Patients with sickle cell anaemia (SCA) have vaso-occlusive crises resulting from occlusive hypoxic-ischaemic injury. Prasugrel inhibits platelet activation and aggregation involved in SCA pathophysiology. Determining Effects of Platelet Inhibition on Vaso-Occlusive Events (DOVE) was a phase 3, double-blind, randomised, placebo-controlled trial assessing prasugrel efficacy. DOVE sought to bring patients' P2Y12 reaction unit (PRU) value within a targeted range via prasugrel dose adjustments using encrypted VerifyNow P2Y12® (VN-P2Y12) point-of-care testing and an interactive voice-response system (IVRS). After PRU determination, randomised patients received 0.08 mg/kg/day prasugrel or placebo. Encrypted PRUs and IVRS provided double-blind dose adjustments to achieve a defined PRU target range of 136-231; placebo patients had mock titrations. Of 341 randomised patients, 166 placebo and 160 prasugrel patients reached the fully titrated dose (FTD). Most prasugrel patients (n=104, 65 %) remained on the initial 0.08 mg/kg dose; doses escalations occurred in 23 % of patients (n=36). Mean PRUs for the pharmacodynamic population at baseline were similar in the prasugrel (273 ± 44.9) and placebo groups (273 ± 51.7), with significant reductions in PRU (p<0.001) for prasugrel patients at the FTD and at 9 months. Concomitant use of hydroxyurea did not affect platelet reactivity at any time. The majority of prasugrel patients (n=135, 84.4 %) at the FTD were within the target range of 136-231 PRUs. Mean VN-P2Y12 percentage inhibition at baseline was similar in the prasugrel (2.8 ± 5.4 %) and placebo groups (2.0 ± 4.7 %); prasugrel patients had significant increases in inhibition (p<0.001) at FTD and at 9 months. Patients with higher PRU values at baseline required higher prasugrel doses to bring PRU within the prespecified range. DOVE is the first study to successfully employ double-blind, real-time, encrypted, point-of-care platelet testing and IVRS to dose-adjust antiplatelet therapy to a targeted range of platelet inhibition.


Assuntos
Anemia Falciforme/tratamento farmacológico , Plaquetas/efeitos dos fármacos , Monitoramento de Medicamentos/métodos , Inibidores da Agregação Plaquetária/administração & dosagem , Testes de Função Plaquetária , Testes Imediatos , Cloridrato de Prasugrel/administração & dosagem , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Doenças Vasculares/prevenção & controle , Adolescente , Anemia Falciforme/sangue , Anemia Falciforme/diagnóstico , Plaquetas/metabolismo , Criança , Pré-Escolar , Método Duplo-Cego , Cálculos da Dosagem de Medicamento , Feminino , Humanos , Masculino , Inibidores da Agregação Plaquetária/efeitos adversos , Cloridrato de Prasugrel/efeitos adversos , Valor Preditivo dos Testes , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos , Receptores Purinérgicos P2Y12/sangue , Receptores Purinérgicos P2Y12/efeitos dos fármacos , Fatores de Tempo , Resultado do Tratamento , Doenças Vasculares/sangue , Doenças Vasculares/diagnóstico
18.
Nutr J ; 15(1): 84, 2016 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-27716304

RESUMO

BACKGROUND: Most patients attending cancer clinics have hypovitaminosis D. Correcting or preventing this abnormal condition could mitigate the emotional and physical complications of their disease, but clinical trials of vitamin D therapy in this setting are hindered by the unavailability of safe, effective and practical loading dose regimens. METHODS: In this single arm open-label pharmacokinetic trial, outpatients with advanced lung cancer consumed 20,000 IU vitamin D daily with the largest meal of the day for 14 days followed by 10,000 IU per day for a further 7 days. Plasma concentrations of 25-hydroxyvitamin D [25(OH)D], parathyroid hormone, calcium, vitamin C and C-reactive protein were measured on protocol days 0, 14 and 21, and serum vitamin D binding protein (VDBP) concentrations on days 0 and 21. As a secondary objective, preliminary information was obtained regarding clinical effects of rapid vitamin D loading on mood and symptoms by administering appropriate questionnaires two times at baseline and after 14 and 21 days of vitamin D therapy. RESULTS: Of the 91 patients enrolled in the study, 85 % had hypovitaminosis D and 41 % had hypovitaminosis C. Plasma VDBP concentrations were in the normal range. The vitamin D load increased the average plasma 25(OH)D concentration to 116 ± 34 nmol/L (mean ± SD); the median concentration was 122 nmol/L (interquartile range 103-134); VDBP concentrations did not change. Final plasma 25(OH)D concentrations were subnormal (<75 nmol/L) for 13 % of the patients and sub-target (<120 nmol/L) for 44 % of them. In most cases, subnormal and sub-target 25(OH)D concentrations were attributable to obesity and/or a low baseline 25(OH)D concentration. Mood and symptom scores did not change significantly throughout the 3-week protocol. CONCLUSION: Hypovitaminosis D and C are very common in outpatients with advanced lung cancer. A vitamin D load of 20,000 IU per day for 14 days failed to achieve the target concentration in 44 % of the participants in this trial. These results suggest that a loading dose of 30,000 IU per day for 14 days would be safe and effective for patients who are obese or at risk of severe hypovitaminosis D. The preliminary nature of the study design, and the failure to achieve target 25(OH)D concentrations for a large proportion of the patients, do not allow any firm conclusion about the clinical effects of correcting hypovitaminosis D in this patient population. Nevertheless, no evidence was obtained that partial correction of hypovitaminosis D greatly improved mood, reduced distress or relieved cancer-related symptoms. This trial was registered at clinicaltrials.gov as NCT01631526.


Assuntos
Deficiência de Ácido Ascórbico/epidemiologia , Neoplasias Pulmonares/sangue , Deficiência de Vitamina D/epidemiologia , Vitamina D/administração & dosagem , Afeto , Idoso , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Disponibilidade Biológica , Proteína C-Reativa/metabolismo , Cálcio/sangue , Relação Dose-Resposta a Droga , Feminino , Humanos , Neoplasias Pulmonares/complicações , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Prevalência , Vitamina D/sangue , Vitamina D/farmacocinética , Deficiência de Vitamina D/tratamento farmacológico , Proteína de Ligação a Vitamina D/sangue
19.
Sci Rep ; 6: 22413, 2016 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-26931059

RESUMO

Neprilysin (NEP) and endothelin converting enzyme-1 (ECE-1) are two enzymes that degrade amyloid beta in the brain. Currently there are no molecules to stimulate the activity of these enzymes. Here we report, the discovery and characterisation of a peptide referred to as K49-P1-20, from the venom of Bothrops asper which directly enhances the activity of both ECE-1 and NEP. This is evidenced by a 2- and 5-fold increase in the Vmax of ECE-1 and NEP respectively. The K49-P1-20 concentration required to achieve 50% of maximal stimulation (AC50) of ECE-1 and NEP was 1.92 ± 0.07 and 1.33 ± 0.12 µM respectively. Using BLITZ biolayer interferometry we have shown that K49-P1-20 interacts directly with each enzyme. Intrinsic fluorescence of the enzymes change in the presence of K49-P1-20 suggesting a change in conformation. ECE-1 mediated reduction in the level of endogenous soluble amyloid beta 42 in cerebrospinal fluid is significantly higher in the presence of K49-P1-20 (31 ± 4% of initial) compared with enzyme alone (11 ± 5% of initial; N = 8, P = 0.005, unpaired t-test). K49-P1-20 could be an excellent research tool to study mechanism(s) of enzyme stimulation, and a potential novel drug lead in the fight against Alzheimer's disease.


Assuntos
Enzimas Conversoras de Endotelina/metabolismo , Fosfolipases A2 do Grupo II/química , Fosfolipases A2 do Grupo II/farmacologia , Neprilisina/metabolismo , Proteínas de Répteis/química , Proteínas de Répteis/farmacologia , Alanina/metabolismo , Sequência de Aminoácidos , Ativação Enzimática/efeitos dos fármacos , Ensaios Enzimáticos , Células HEK293 , Humanos , Cinética , Peptídeos/química , Peptídeos/metabolismo , Domínios Proteicos , Relação Estrutura-Atividade
20.
Biochem Biophys Res Commun ; 473(1): 47-53, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-26995091

RESUMO

Apoptosis repressor with caspase recruitment domain (ARC), an endogenous inhibitor of apoptosis, is upregulated in a number of human cancers, thereby conferring drug resistance and giving a rationale for the inhibition of ARC to overcome drug resistance. Our hypothesis was that ARC would be similarly upregulated and targetable for therapy in renal cell carcinoma (RCC). Expression of ARC was assessed in 85 human RCC samples and paired non-neoplastic kidney by qPCR and immunohistochemistry, as well as in four RCC cell lines by qPCR, Western immunoblot and confocal microscopy. Contrary to expectations, ARC was significantly decreased in the majority of clear cell RCC and in three (ACHN, Caki-1 and 786-0) of the four RCC cell lines compared with the HK-2 non-cancerous human proximal tubular epithelial cell line. Inhibition of ARC with shRNA in the RCC cell line (SN12K1) that had shown increased ARC expression conferred resistance to Sunitinib, and upregulated interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF). We therefore propose that decreased ARC, particularly in clear cell RCC, confers resistance to targeted therapy through restoration of tyrosine kinase-independent alternate angiogenesis pathways. Although the results are contrary to expectations from other cancer studies, they were confirmed here with multiple analytical methods. We believe the highly heterogeneous nature of cancers like RCC predicate that expression patterns of molecules must be interpreted in relation to respective matched non-neoplastic regions. In the current study, this procedure indicated that ARC is decreased in RCC.


Assuntos
Carcinoma de Células Renais/metabolismo , Proteínas do Citoesqueleto/metabolismo , Resistencia a Medicamentos Antineoplásicos , Indóis/uso terapêutico , Neoplasias Renais/metabolismo , Neovascularização Patológica , Proteínas do Tecido Nervoso/metabolismo , Pirróis/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/química , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Immunoblotting , Imuno-Histoquímica , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Sunitinibe , Fator A de Crescimento do Endotélio Vascular/metabolismo
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