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1.
Sci Rep ; 14(1): 20149, 2024 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-39209906

RESUMO

In the pharmaceutical industry, there is an abundance of regulatory documents used to understand the current regulatory landscape and proactively make project decisions. Due to the size of these documents, it is helpful for project teams to have informative summaries. We propose a novel solution, MedicoVerse, to summarize such documents using advanced machine learning techniques. MedicoVerse uses a multi-stage approach, combining word embeddings using the SapBERT model on regulatory documents. These embeddings are put through a critical hierarchical agglomerative clustering step, and the clusters are organized through a custom data structure. Each cluster is summarized using the bart-large-cnn-samsum model, and each summary is merged to create a comprehensive summary of the original document. We compare MedicoVerse results with established models T5, Google Pegasus, Facebook BART, and large language models such as Mixtral 8 × 7b instruct, GPT 3.5, and Llama-2-70b by introducing a scoring system that considers four factors: ROUGE score, BERTScore, business entities and the Flesch Reading Ease. Our results show that MedicoVerse outperforms the compared models, thus producing informative summaries of large regulatory documents.


Assuntos
Aprendizado de Máquina , Análise por Conglomerados , Indústria Farmacêutica , Humanos , Processamento de Linguagem Natural
2.
Mol Pharm ; 12(10): 3724-34, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26355665

RESUMO

Combretastatin A4 disodium phosphate (CA4P) is a fluorescent, water-soluble prodrug able to induce vascular shutdown within tumors at doses less than one-tenth of the maximum tolerated dose. As a continued effort to develop efficient liposomal CA4P to treat solid tumor, we herein investigate the physical and spectroscopic properties of CA4P in aqueous solution and the mechanism of CA4P release from archaeal tetraether liposomes (archaeosomes). We found that cis-CA4P can be photoisomerized to trans-CA4P. This photoisomerization results in an increase in fluorescence intensity. Both cis- and trans-CA4P undergo fluorescence intensity self-quenching after they reach a critical concentration Cq (∼0.15-0.25 mM). Moreover, both cis- and trans-CA4P in buffer exhibit a red shift in their excitation spectrum and an increase in excitation spectrum band sharpness with increasing concentration, which can be attributed to the formation of J-aggregates. The onset of the dramatic change in excitation maximum occurs at concentrations close to Cq, suggesting that the self-quenching arises from extensive J-aggregate formation and that, when CA4P concentration exceeds Cq, J-aggregate formation begins to increase sharply. Our data also suggest that the extent of J-aggregate formation plays a critical role in CA4P release from tetraether archaeosomes and in the subsequent cytotoxicity on cultured human breast cancer MCF-7 cells. The drug leakage and cytotoxicity rate constants vary with the initial CA4P concentration entrapped inside archaeosomes in a biphasic manner, reaching a local maximum at 0.25-0.50 mM. A mechanism based on the concept of J-aggregate formation has been proposed to explain the biphasic changes in drug release and cytotoxicity with increasing drug concentration. Tetraether archaeosomes are extraordinarily stable and relatively nontoxic to animals; thus, they are promising nano drug carriers. The results obtained from this study pave the way for future development of archaeosomal CA4P to treat solid tumors.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Lipossomos/metabolismo , Células MCF-7/efeitos dos fármacos , Estilbenos/farmacocinética , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Feminino , Corantes Fluorescentes/metabolismo , Humanos , Células MCF-7/metabolismo , Estilbenos/farmacologia
3.
Archaea ; 2012: 138439, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23028246

RESUMO

This paper reviews the recent findings related to the physical properties of tetraether lipid membranes, with special attention to the effects of the number, position, and configuration of cyclopentane rings on membrane properties. We discuss the findings obtained from liposomes and monolayers, composed of naturally occurring archaeal tetraether lipids and synthetic tetraethers as well as the results from computer simulations. It appears that the number, position, and stereochemistry of cyclopentane rings in the dibiphytanyl chains of tetraether lipids have significant influence on packing tightness, lipid conformation, membrane thickness and organization, and headgroup hydration/orientation.


Assuntos
Lipídeos/química , Lipossomos/química , Membranas/química , Ciclopentanos/análise , Estrutura Molecular
4.
Free Radic Biol Med ; 48(2): 306-17, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19897030

RESUMO

Nitric oxide (NO) and other reactive nitrogen species target multiple sites in the mitochondria to influence cellular bioenergetics and survival. Kinetic imaging studies revealed that NO from either activated macrophages or donor compounds rapidly diffuses to the mitochondria, causing a dose-dependent progressive increase in NO-dependent DAF fluorescence, which corresponded to mitochondrial membrane potential loss and initiated alterations in cellular bioenergetics that ultimately led to necrotic cell death. Cellular dysfunction is mediated by an elevated 3-nitrotyrosine signature of the mitochondrial complex I subunit NDUFB8, which is vital for normal mitochondrial function as evidenced by selective knockdown via siRNA. Overexpression of mitochondrial superoxide dismutase substantially decreased NDUFB8 nitration and restored mitochondrial homeostasis. Further, treatment of cells with either necrostatin-1 or siRNA knockdown of RIP1 and RIP3 prevented NO-mediated necrosis. This work demonstrates that the interaction between NO and mitochondrially derived superoxide alters mitochondrial bioenergetics and cell function, thus providing a molecular mechanism for reactive oxygen and nitrogen species-mediated alterations in mitochondrial homeostasis.


Assuntos
Complexo I de Transporte de Elétrons/metabolismo , Endotélio Vascular/metabolismo , Fibroblastos/metabolismo , Macrófagos/metabolismo , Mitocôndrias/metabolismo , Animais , Linhagem Celular , Complexo I de Transporte de Elétrons/genética , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Humanos , Imidazóis/farmacologia , Indóis/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Potencial da Membrana Mitocondrial , Camundongos , Microscopia de Fluorescência , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Necrose/genética , Óxido Nítrico/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Subunidades Proteicas/metabolismo , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ratos , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
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