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1.
Bioorg Med Chem Lett ; 80: 129084, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36423823

RESUMO

In the treatment of non-small cell lung cancer (NSCLC), patients harboring exon 20 insertion mutations in the epidermal growth factor receptor (EGFR) gene (EGFR) have few effective therapies because this subset of mutants is generally resistant to most currently approved EGFR inhibitors. This report describes the structure-guided design of a novel series of potent, irreversible inhibitors of EGFR exon 20 insertion mutations, including the V769_D770insASV and D770_N771insSVD mutants. Extensive structure-activity relationship (SAR) studies led to the discovery of mobocertinib (compound 21c), which inhibited growth of Ba/F3 cells expressing the ASV insertion with a half-maximal inhibitory concentration of 11 nM and with selectivity over wild-type EGFR. Daily oral administration of mobocertinib induced tumor regression in a Ba/F3 ASV xenograft mouse model at well-tolerated doses. Mobocertinib was approved in September 2021 for the treatment of adult patients with advanced NSCLC with EGFR exon 20 insertion mutations with progression on or after platinum-based chemotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Camundongos , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutagênese Insercional , Mutação , Receptores ErbB , Éxons , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
2.
NMR Biomed ; 34(7): e4526, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33880799

RESUMO

In acute-ischemic-stroke patients, penumbra assessment plays a significant role in treatment outcome. MR perfusion-weighted imaging (PWI) and diffusion-weighted imaging (DWI) mismatch ratio can provide penumbra assessment. Recently reported studies have shown the potential of susceptibility-weighted imaging (SWI) in the qualitative assessment of penumbra. We hypothesize that quantitative penumbra assessment using SWI-DWI can provide an alternative to the PWI-DWI approach and this can also reduce the overall scan-time. The purpose of the current study was to develop a framework for accurate quantitative assessment of penumbra using SWI-DWI and its validation with PWI-DWI-based quantification. In the current study, the arterial-spin-labelling (ASL) technique has been used for PWI. This retrospective study included 25 acute-ischemic-stroke patients presenting within 24 hours of the last noted baseline condition of stroke onset. Eleven patients also had follow-up MRI within 48 hours. MRI acquisition comprised DWI, SWI, pseudo-continuous-ASL (pCASL), FLAIR and non-contrast-angiography sequences. A framework was developed for the enhancement of prominent hypo-intense vein signs followed by automatic segmentation of the SWI penumbra ROI. Apparent-diffusion-coefficient (ADC) maps and cerebral-blood-flow (CBF) maps were computed. The infarct core ROI from the ADC map and the ASL penumbra ROI from CBF maps were segmented semiautomatically. The infarct core volume, SWI penumbra volume (SPV) and pCASL penumbra volume were computed and used to calculate mismatch ratios MRSWIADC and MRCBFADC . The Dice coefficient between the SWI penumbra ROI and ASL penumbra ROI was 0.96 ± 0.07. MRSWIADC correlated well (r = 0.90, p < 0.05) with MRCBFADC , which validates the hypothesis of accurate penumbra assessment using the SWI-DWI mismatch ratio. Moreover, a significant association between high SPV and the presence of vessel occlusion in the MR angiogram was observed. Follow-up data showed salvation of penumbra tissue (location and volumes predicted by proposed framework) by treatments. Additionally, functional-outcome analysis revealed 93.3% of patients with MRSWIADC > 1 benefitted from revascularization therapy. Overall, the proposed automated quantitative assessment of penumbra using the SWI-DWI mismatch ratio performs equivalently to the ASL PWI-DWI mismatch ratio. This approach provides an alternative to the perfusion sequence required for penumbra assessment, which can reduce scan time by 17% for the protocol without a perfusion sequence.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Artérias Cerebrais/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , AVC Isquêmico/diagnóstico por imagem , Perfusão , Marcadores de Spin , Acidente Vascular Cerebral/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade
3.
Indian J Med Res ; 154(6): 813-822, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-35662086

RESUMO

Background & objectives: Pre-eclampsia has remained an elusive disease with serious impacts on both maternal and foetal health. Two novel markers, annexin A5 (ANXA5) and apelin are currently of considerable interest. The present study aimed to determine the placental expression of ANXA5 and apelin in pre-eclamptic placentae and also to elucidate if there is any correlation between the expression of these markers and the clinical features of both, mother and neonate. The comparison between gross and histopathological features of pre-eclamptic placentae and controls was another objective. Methods: A prospective, observational study was undertaken for one year. Placentae of pre-eclamptic patients and matched controls (matched for age, ethnic and socio-economic background) were collected along with the clinical data. Gross and histopathological analyses were done and immunohistochemical study of placental sections with ANXA5 and apelin was also undertaken. Results: 79 pre-eclamptic patients and equal numbers of matched controls were included in the study. The difference in weight and dimensions of placentae between the pre-eclampsia group and matched controls was significant. Histopathological features noted in the pre-eclamptic placentae included decidual vasculopathy, infarction, perivillous fibrin deposition, increased syncytial knots and distal villous hypoplasia. There was a significant reduction in the expression of both ANXA5 and apelin in pre-eclamptic placentae compared to controls. Among pre-eclamptic patients, the intensity of ANXA5 and apelin expression showed a significant association with respect to neonatal resuscitation. Furthermore, the intensity of apelin showed expression a significant correlation with the requirement of sick neonatal care unit treatment. Interpretation & conclusions: The results of the present study suggest that both ANXA5 and apelin levels are reduced in pre-eclamptic placentae. Hence, it is recommended to further explore the impact of these markers on pregnancy outcomes by undertaking randomized controlled trials.


Assuntos
Pré-Eclâmpsia , Anexina A5/genética , Anexina A5/metabolismo , Apelina/genética , Apelina/metabolismo , Feminino , Humanos , Recém-Nascido , Placenta/patologia , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/patologia , Gravidez , Estudos Prospectivos , Ressuscitação
4.
Nucleic Acids Res ; 47(7): 3306-3320, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-30820542

RESUMO

For oligonucleotide therapeutics, chemical modifications of the sugar-phosphate backbone are frequently used to confer drug-like properties. Because 2'-deoxy-2'-fluoro (2'-F) nucleotides are not known to occur naturally, their safety profile was assessed when used in revusiran and ALN-TTRSC02, two short interfering RNAs (siRNAs), of the same sequence but different chemical modification pattern and metabolic stability, conjugated to an N-acetylgalactosamine (GalNAc) ligand for targeted delivery to hepatocytes. Exposure to 2'-F-monomer metabolites was low and transient in rats and humans. In vitro, 2'-F-nucleoside 5'-triphosphates were neither inhibitors nor preferred substrates for human polymerases, and no obligate or non-obligate chain termination was observed. Modest effects on cell viability and mitochondrial DNA were observed in vitro in a subset of cell types at high concentrations of 2'-F-nucleosides, typically not attained in vivo. No apparent functional impact on mitochondria and no significant accumulation of 2'-F-monomers were observed after weekly administration of two GalNAc-siRNA conjugates in rats for ∼2 years. Taken together, the results support the conclusion that 2'-F nucleotides can be safely applied for the design of metabolically stabilized therapeutic GalNAc-siRNAs with favorable potency and prolonged duration of activity allowing for low dose and infrequent dosing.


Assuntos
Acetilgalactosamina/efeitos adversos , Acetilgalactosamina/química , Desoxirribonucleotídeos/efeitos adversos , Desoxirribonucleotídeos/química , Flúor/química , RNA Interferente Pequeno/efeitos adversos , RNA Interferente Pequeno/química , Animais , Feminino , Flúor/efeitos adversos , Humanos , Masculino , Ratos , Ratos Sprague-Dawley
5.
J Stroke Cerebrovasc Dis ; 26(6): 1266-1273, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28237123

RESUMO

BACKGROUND: Acute ischemic stroke (AIS) is a time-dependent treatable cause of morbidity and mortality. Despite the increasing stroke incidence in developing countries, parallel increasing stroke thrombolysis rates have not been documented. AIM: This study aims to determine trends in patient characteristics and rates of recombinant tissue plasminogen activator (rtPA) use in AIS patients in a tertiary care center in northern India. METHODS: All AIS patients presenting within 8 hours of symptoms onset from January 2011 to December 2015 were enrolled and analyzed. RESULTS: A total of 867 AIS patients presented within 8 hours of symptoms onset. Out of 593 eligible patients, 189 (31.87%) underwent intravenous thrombolysis (IVT) with rtPA within 4.5 hours of the window period. Patients (undergoing) IVT had onset-to-door times of 2 hours or less (23.81%), 2-3 hours (33.86%), and 3.0-4.5 hours (42.33%). IVT rates in 2 hours or less of symptom onset increased from 22% to 25% and IVT rates in 2-3 hours increased from 38.9% to 43.8%. Door-to-computerized tomographic time (median 27 versus 11 minutes, P = .0001) and door-to-needle time (median 83 versus 67 minutes, P = .011) improved, with a significant improvement of computerized tomography imaging time within 25 minutes of arrival (from 50% to 78.4%, P = .014). Post-IVT symptomatic hemorrhage was noted in 5 patients (2.65%). The median National Institutes of Health Stroke Scale score at presentation was 11, whereas a favorable modified Rankin Scale score (0-1) at 3 months was seen in 39.68%. CONCLUSIONS: Encouraging trends in IVT over the years may be indicative of increasing community awareness of stroke and improving quality of stroke care in developing countries such as India.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/administração & dosagem , Padrões de Prática Médica/tendências , Avaliação de Processos em Cuidados de Saúde/tendências , Acidente Vascular Cerebral/tratamento farmacológico , Centros de Atenção Terciária/tendências , Terapia Trombolítica/tendências , Ativador de Plasminogênio Tecidual/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico por imagem , Angiografia Cerebral/tendências , Angiografia por Tomografia Computadorizada/tendências , Avaliação da Deficiência , Esquema de Medicação , Feminino , Humanos , Índia , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Melhoria de Qualidade , Indicadores de Qualidade em Assistência à Saúde , Proteínas Recombinantes/administração & dosagem , Acidente Vascular Cerebral/diagnóstico por imagem , Fatores de Tempo , Tempo para o Tratamento/tendências , Resultado do Tratamento
6.
Beilstein J Nanotechnol ; 15: 909-924, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39076688

RESUMO

Nanoparticles (NPs) are considered as versatile tools in various fields including medicine, electronics, and environmental science. Understanding the structural aspects of surface modifiers in nanoparticles that govern their cellular uptake is crucial for optimizing their efficacy and minimizing potential cytotoxicity. The cellular uptake is influenced by multiple factors, namely, size, shape, and surface charge of NPs, as well as their surface functionalization. In the current study, classification-based ML models (i.e., Bayesian classification, random forest, support vector classifier, and linear discriminant analysis) have been developed to identify the features/fingerprints that significantly contribute to the cellular uptake of ENMOs in multiple cell types, including pancreatic cancer cells (PaCa2), human endothelial cells (HUVEC), and human macrophage cells (U937). The best models have been identified for each cell type and analyzed to detect the structural fingerprints/features governing the cellular uptake of ENMOs. The study will direct scientists in the design of ENMOs of higher cellular uptake efficiency for better therapeutic response.

11.
Bioanalysis ; 15(14): 833-843, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37584364

RESUMO

Aim: Aur0101 is a cytotoxic and small-molecule microtubule depolymerizing agent, and is the payload conjugated to antibody-drug conjugate PYX-201. Developing and validating a sensitive bioanalytical method to quantitate Aur0101 was novel and crucial in preclinical PYX-201 studies. Materials & methods: Reference standard Aur0101 and its stable isotope labelled internal standard Aur0101-d8 were used in this LC-MS/MS method. Results: This sensitive assay was validated at a lower limit of quantitation of 15 pg/ml and successfully applied to support preclinical rat and monkey toxicology studies. Preclinical plasma toxicokinetic parameters were presented. Conclusion: A sensitive and robust LC-MS/MS assay was validated for Aur0101 in rat and monkey plasma.


Assuntos
Antineoplásicos , Imunoconjugados , Ratos , Animais , Cromatografia Líquida/métodos , Haplorrinos , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes
12.
J Pharm Biomed Anal ; 233: 115452, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37167766

RESUMO

PYX-201 is an investigative ADC oncology drug composed of a monoclonal human immunoglobulin G (IgG) antibody targeting the extra domain B splice variant of fibronectin (EDB + FN) conjugated to an auristatin payload through a cleavable linker. Effective measurement of PYX-201 tAb is the key to ADC drug PYX-201 preclinical pharmacokinetics (PK) assessment. PYX-201 monoclonal antibody (mAb) was used as the reference standard, goat anti-human IgG polyclonal antibody (pAb) or rabbit anti-human Kappa light chain mAb was employed as the capture antibody, and mouse mAb or goat pAb anti-human IgG the crystallizable fragment (Fc) (horseradish peroxidase (HRP)) was utilized as the detection antibody in this ELISA. This assay was validated with a dynamic range 250 - 10,000 ng/mL and 250 - 6000 ng/mL in rat and monkey K2EDTA plasma, respectively. PYX-201 tAb bioanalytical ELISA assay was reported for the first time in any biological matrix. This is the first time for a bioanalytical method to be validated for a tAb from an ADC drug targeting EDB + FN in any biological matrix.


Assuntos
Imunoconjugados , Camundongos , Ratos , Animais , Coelhos , Ensaio de Imunoadsorção Enzimática , Anticorpos Monoclonais , Peroxidase do Rábano Silvestre , Imunoglobulina G
13.
Bioanalysis ; 15(1): 43-52, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36876967

RESUMO

Aim: PYX-201 is a novel antibody-drug conjugate targeting the extra domain B splice variant of fibronectin in the tumor microenvironment. Accurate quantification of PYX-201 is critical for PYX-201 pharmacokinetics profiling in preclinical studies. Materials & methods: ELISA was performed using reference standard PYX-201, mouse monoclonal anti-monomethyl auristatin E antibody, mouse IgG1, mouse monoclonal anti-human IgG horseradish peroxidase and donkey anti-human IgG horseradish peroxidase. Results: This assay was validated at 50.0-10,000 ng/ml in rat dipotassium EDTA plasma and 250-10,000 ng/ml in monkey dipotassium EDTA plasma. Conclusion: This is the first time for a PYX-201 bioanalytical assay in any matrix to be reported.


Assuntos
Imunoconjugados , Ratos , Camundongos , Animais , Ácido Edético , Ensaio de Imunoadsorção Enzimática , Imunoglobulina G
15.
Diabetes Metab Syndr ; 16(3): 102435, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35245857

RESUMO

BACKGROUND AND AIMS: Gestational diabetes mellitus (GDM) is one of the commonest medical complications of pregnancy. Annexin A5 (ANXA5) is a protein, found in apical surfaces of syncytiotrophoblasts, which prevents fetal and placental vascular thrombosis in GDM. Apelin is a bioactive peptide which has been linked to GDM. The aim of the present study was to correlate macroscopic as well as microscopic changes and immunohistochemical expression of ANXA5 and apelin in placentae of GDM with maternal and neonatal clinical features and also to compare the results with those in matched controls. METHODS: This prospective observational study was undertaken for a period of one year from April 2020 to March 2021. It comprised of 42 patients of GDM. Gross features, microscopic features and intensity and grade of expression of ANXA5 and Apelin were analyzed in placentae of GDM. RESULTS: Morphological changes detected in GDM placentae included increased immature villi (16 cases, 38%), increased syncytial knots (36, 86%), perivillous fibrin deposition (20, 48%), fibrosis of villous stroma (20, 48%), presence of nucleated red blood cells (12, 28.5%) and hypervascularity (34, 81%). The extent of histopathological changes noted in GDM placentae was significantly higher than that in matched controls. GDM placentae showed significantly reduced expression of ANXA5 and Apelin in terms of grade and intensity when compared with matched controls. Reduced expression (mild intensity) of ANXA5 was noted in 22 GDM cases (52.3%) whereas apelin expression was of weak intensity in 26 (61.9%) cases. Among GDM patients, statistically significant association was noted between ANXA5 intensity and neonatal resuscitation, apelin grade and preterm birth as well as low birth weight and apelin intensity and requirement of treatment in sick neonatal care unit. CONCLUSION: The placental expression of the proteins, ANXA5 and Apelin, is altered in GDM though their exact pathogenetic mechanisms are yet to be understood. They can be targets for development of prophylactic and therapeutic agents in future.


Assuntos
Anexina A5 , Apelina , Diabetes Gestacional , Nascimento Prematuro , Anexina A5/genética , Anexina A5/metabolismo , Apelina/genética , Apelina/metabolismo , Feminino , Humanos , Recém-Nascido , Placenta/irrigação sanguínea , Placenta/metabolismo , Placenta/patologia , Gravidez , Nascimento Prematuro/metabolismo , Nascimento Prematuro/patologia , Ressuscitação
18.
Cancer Discov ; 11(7): 1672-1687, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33632773

RESUMO

Most EGFR exon 20 insertion (EGFRex20ins) driver mutations in non-small cell lung cancer (NSCLC) are insensitive to approved EGFR tyrosine kinase inhibitors (TKI). To address the limitations of existing therapies targeting EGFR-mutated NSCLC, mobocertinib (TAK-788), a novel irreversible EGFR TKI, was specifically designed to potently inhibit oncogenic variants containing activating EGFRex20ins mutations with selectivity over wild-type EGFR. The in vitro and in vivo activity of mobocertinib was evaluated in engineered and patient-derived models harboring diverse EGFRex20ins mutations. Mobocertinib inhibited viability of various EGFRex20ins-driven cell lines more potently than approved EGFR TKIs and demonstrated in vivo antitumor efficacy in patient-derived xenografts and murine orthotopic models. These findings support the ongoing clinical development of mobocertinib for the treatment of EGFRex20ins-mutated NSCLC. SIGNIFICANCE: No oral EGFR-targeted therapies are approved for EGFR exon 20 insertion (EGFRex20ins) mutation-driven NSCLC. Mobocertinib is a novel small-molecule EGFR inhibitor specifically designed to target EGFRex20ins mutants. Preclinical data reported here support the clinical development of mobocertinib in patients with NSCLC with EGFR exon 20 insertion mutations.See related commentary by Pacheco, p. 1617.This article is highlighted in the In This Issue feature, p. 1601.


Assuntos
Compostos de Anilina/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Éxons , Indóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Pirimidinas/uso terapêutico , Compostos de Anilina/farmacologia , Animais , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral/efeitos dos fármacos , Receptores ErbB , Humanos , Indóis/farmacologia , Neoplasias Pulmonares/genética , Camundongos , Mutagênese Insercional , Pirimidinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
19.
IET Nanobiotechnol ; 14(7): 609-616, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33010137

RESUMO

Logic expressions can be designed from actin filaments. It is a protein that makes the cellular structure and plays an important role in intracellular communication. Nano communication technique has been established using actin cellular automata. Among several rules, (1, 30) and (4, 27) rules have been used to design 2 to 1 multiplexer, 4 to 1 multiplexer, 1 to 2 demultiplexer and 1 to 4 demultiplexer. Router or data selector has been made of using multiplexer and demultiplexer. Three novel circuits such as multiplexer, demultiplexer and nano-router have been designed using the projected mechanism. The primary focus of this proposed technique is on different designs of the multiplexer, demultiplexer and minimum cell count with minimum time steps. The different router circuits have been simulated with the help of Simulink by which output has been verified for different circuits. Stuck at fault analysis is also done in this study. Device density and power consumption have also been included in this study. A comparative analysis of the different designs of the router provides a better concept of circuit optimisation. Furthermore, this study analyses convenient forthcoming applications in nano-technology and nano-bio-molecular systems involving the proposed parameters.


Assuntos
Actinas/química , Algoritmos , Nanotecnologia/métodos , Teoria Quântica , Animais , Comunicação Celular , Simulação por Computador , Lógica , Coelhos , Reprodutibilidade dos Testes , Semicondutores , Processamento de Sinais Assistido por Computador , Transdução de Sinais , Biologia Sintética , Temperatura , Transativadores/genética
20.
Asian J Neurosurg ; 15(3): 706-708, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33145234

RESUMO

Recently, tenecteplase (TNK) has been used for intravenous thrombolysis in acute ischemic stroke (AIS). Although spontaneous subarachnoid hemorrhage (SAH) following thrombolysis with tissue plasminogen activator has been reported, there is a lack of literature regarding TNK-induced nonaneurysmal spontaneous SAH. Our index case received intravenous TNK within an hour of symptom onset of AIS. Following deterioration of sensorium, repeat noncontrast computed tomography was performed, which showed diffuse SAH. Cerebral angiography did not reveal any aneurysm. Nonaneurysmal SAH can be a complication of TNK thrombolysis, which is not reported in literature. Knowledge of this possible adverse reaction is critical for appropriate counseling and management.

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