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1.
Ann Pharm Fr ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38821483

RESUMO

Enzymes are a key part of most metabolic processes and are required for the correct functioning of the human body, either directly or indirectly. Proteolytic enzymes aid in the digestion of proteins in the body. Proteolytic enzymes are created in the pancreas naturally, but they can also be found in certain diets. Serratiopeptidase is an enzyme found in the stomach wall of silkworms and produced from S. marcescens strain. Less solubility, toxicity, instability, incompatibility, and less penetration are all common issues with Serratiopeptidase drug delivery. Because of its proteinaceous nature, serratiopeptidase is susceptible to enzymatic breakdown in the gastrointestinal system. It also has a low permeability through the intestinal barrier due to its hydrophilic nature. Depending on the features of the medicine, a suitable delivery mechanism is required. Topical formulation may eliminate the risk of gastric degradation of drug and increase direct permeation through skin and show effects. Topical SRP may effectively lower inflammatory markers, as it has been found to have superior anti-inflammatory effects than topical NSAIDs. Serratiopeptidase topical formulations could be more effective than nonsteroidal anti-inflammatory medications in treating local inflammation. This article reviews studies on various topical formulations.

2.
Ann Pharm Fr ; 82(2): 203-228, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38159721

RESUMO

The quality pioneer Dr. Joseph M. Juran first proposed the idea of quality by design. According to him, pharmaceutical quality by design is an organised approach to product development that starts with predetermined goals and places an emphasis on product, process understanding, control based on reliable science and quality risk management. The quality of a product or process can typically be affected by a number of input elements. Design of experiments has been employed widely recently to understand the impacts of multidimensional and interactions of input parameters on the output responses of analytical procedures and pharmaceutical goods. Depending on the design of experiments objectives, screening, characterization, or optimization of the process and formulation, a variety of designs, such as factorial or mixture, can be used. The most popular designs used in the stage of screening or factor selection are the 2-Level Factorial and Plackett-Burman designs, both of which have two levels for each factor (k), both economical and effective, and in optimization widely used designs in this step are full factorial at three levels, central composite, Box-Behnken design. The analysis of variance, regression significance, and lack of fit of the regression model were some of the key topics covered in the discussion of the main components of multiple regression model adjustment. Design of experiments is thus the primary element of the formulation and analytical quality by design. The details about design of experiments used for the analysis of pharmaceutical formulation using HPLC.


Assuntos
Gestão de Riscos , Cromatografia Líquida de Alta Pressão/métodos , Preparações Farmacêuticas
3.
J Sep Sci ; 45(18): 3422-3430, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35839084

RESUMO

Saccharides, especially anhydro sugars present in atmospheric aerosols, can be used as tracers to track sources of atmospheric aerosols. High-performance anion-exchange chromatography with pulsed amperometric detection is a commonly used technique for determining these saccharides, but the reported methods suffer from three drawbacks. First, to achieve separation of the complete set of atmospheric saccharides, run times are very long, typically longer than 60 minutes. Second, some methods require two columns to achieve the desired separation. Finally, in an era when electrolytic eluent preparation allows for excellent precision and accuracy, these methods require manually prepared eluents, which can lead to separation inconsistency for closely eluting analytes. These drawbacks make existing methods difficult to automate. To address this issue, we developed a fast method that uses only a single column for separation and electrolytically generated eluent that resolves 12 key atmospheric aerosol saccharides in 20 minutes. The resolved saccharides include anhydro sugars (levoglucosan, galactosan, and mannosan), sugar alcohols (erythritol, xylitol, and mannitol), and mono-/disaccharides (arabinose, galactose, glucose, mannose, fructose, and sucrose). To our knowledge, this report is the first instance of achieving such a significant reduction in run time with good resolution for this set of saccharides.


Assuntos
Galactose , Manose , Aerossóis/análise , Ânions , Arabinose , Carboidratos/análise , Cromatografia/métodos , Dissacarídeos , Eritritol , Frutose , Galactose/análise , Glucose/análise , Manitol , Manose/análise , Manose/química , Sacarose , Álcoois Açúcares , Açúcares , Xilitol
4.
J Liposome Res ; 29(3): 291-311, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30526186

RESUMO

Melanoma is the most deadly and life-threatening form of skin cancer with progressively higher rates of incidence worldwide. The objective of the present investigation is to develop and to statistically optimize and characterize curcumin (CUR) loaded ethosomes for treatment of melanoma. A two factor, three level (32) factorial design approach was employed for the optimization of ethosomes. The prepared ethosomes were evaluated for size, zeta potential, entrapment efficiency, in vitro skin permeation and deposition ability. The optimized ethosomal formulation was evaluated for in vitro cytotoxicity and cellular uptake studies using A375 human melanoma cells. The optimized formulation has imperfect round shaped unilamellar structures with a mean vesicle size of 247 ± 5.25 nm and an entrapment efficiency of 92.24 ± 0.20%. The in vitro skin permeation studies proved the superiority of ethosomes over the traditional liposomes in terms of the amount of drug permeated and deposited in skin layers. Fluorescence microscopy showed the enhanced penetration of ethosomes into the deeper layers of the skin. In vitro cytotoxicity and cellular uptake studies revealed that curcumin ethosomes have significantly improved cytotoxicity and cellular uptake in A375 human melanoma cell lines. The colony formation assay results showed that curcumin ethosomes have a superior antiproliferative effect as they effectively inhibit the clonogenic ability of A375 cells. The flow cytometry results indicate that curcumin ethosomes induce cell death in A375 cells by apoptosis mechanism. The present study provides a strong rationale and motivation for further investigation of newly developed curcumin ethosomes as a potential therapeutic strategy for melanoma treatment.


Assuntos
Antineoplásicos/química , Curcumina/química , Lipossomos/química , Nanocápsulas/química , Neoplasias Cutâneas/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Curcumina/administração & dosagem , Liberação Controlada de Fármacos , Humanos , Tamanho da Partícula , Permeabilidade , Fosfatidilcolinas/química , Ratos , Pele/metabolismo , Absorção Cutânea
5.
Mo Med ; 116(4): 291-296, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31527977

RESUMO

BACKGROUND: As guidelines do not describe how to develop a multi-disciplinary team(MDT), we provide a model using quality improvement tools to design a MDT for infective endocarditis (IE). METHODS: Primary service, specialty teams and whether they had surgery or not (indications, reasons, outcomes and complications) were recorded for IE patients for January-December 2016. Criteria: age >18years and definite IE per modified Duke criteria. RESULTS: Of all cases, 29/82 met criteria. Primary service: internal medicine 18(62.1%), medical intensive care and cardiology 4(13.8%) each, family medicine 2(7.9%) and pediatrics 1(3.4%). Surgery was indicated in 21(72.4%), 9 (42.9%) underwent surgery, 12 (57.1%) did not [6/9(66.67%) left side IE died, all right side IE (3,25%) survived] and 2 (22.2%) had missed opportunities and this was chosen as the leverage point. MDT was developed to reduce the number of left sided IE patients not undergoing surgery despite indications. CONCLUSIONS: Quality improvement and team development tools help in developing MDT for IE.


Assuntos
Endocardite/terapia , Equipe de Assistência ao Paciente/organização & administração , Melhoria de Qualidade/organização & administração , Endocardite/diagnóstico , Endocardite/cirurgia , Humanos , Missouri , Desenvolvimento de Programas
6.
J Proteome Res ; 17(4): 1559-1574, 2018 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-29451981

RESUMO

Comprehensive characterization of the N-glycome of a therapeutic is challenging because glycans may harbor numerous modifications (e.g., phosphorylation, sulfation, sialic acids with possible O-acetylation). The current report presents a comparison of two chromatographic platforms for the comprehensive characterization of a recombinant human erythropoietin (rhEPO) N-glycome. The two platforms include a common workflow based on 2-AB-derivatization and hydrophilic interaction chromatography (HILIC) and a native N-linked glycan workflow employing high performance anion exchange (HPAE) chromatography. Both platforms were coupled to an Orbitrap mass spectrometer, and data dependent HCD fragmentation allowed confident structural elucidation of the glycans. Each platform identified glycans not revealed by the other, and both exhibited strengths and weaknesses. The reductive amination based HILIC workflow provided better throughput and sensitivity, had good isomer resolution, and revealed the presence of O-acetylated sialic acids. However, it exhibited poor performance toward phosphorylated glycans and did not reveal the presence of sulfated glycans. Furthermore, reductive amination introduced dehydration artifacts and modified the glycosylation profile in the rhEPO glycome. Conversely, HPAE provided unbiased charge classification (sialylation levels), improved isomer resolution, and revealed multiple phosphorylated and sulfated structures, but delivered lower throughput, had artifact peaks due to epimer formation, and loss of sialic acid O-acetylation. The MS2 based identification of phosphorylated and sulfated glycans was not possible in HILIC mode due to their poor solubility caused by the high acetonitrile concentrations employed at the beginning of the gradient. After analyzing the glycome by both approaches and determining the glycans present, a glycan library was created for site specific glycopeptide analyses. Glycopeptide analyses confirmed all the compositions annotated by the combined use of 2-AB- and native glycan workflows and provided site specific location of the glycans. These two platforms were complementary and in combination delivered a more thorough and comprehensive characterization of the rhEPO N-glycome, supporting regulatory conformance for the pharmaceutical industry.


Assuntos
Técnicas de Química Analítica/métodos , Eritropoetina/química , Polissacarídeos/análise , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Humanos , Interações Hidrofóbicas e Hidrofílicas , Espectrometria de Massas , Fosforilação , Proteínas Recombinantes/química , Ácidos Siálicos , Sulfatos , Fluxo de Trabalho
7.
J Am Chem Soc ; 140(1): 143-146, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29272114

RESUMO

CRISPR/Cas9 is a combined protein (Cas9) and an engineered single guide RNA (sgRNA) genome editing platform that offers revolutionary solutions to genetic diseases. It has, however, a double delivery problem owning to the large protein size and the highly charged RNA component. In this work, we report the first example of CRISPR/Cas9 encapsulated by nanoscale zeolitic imidazole frameworks (ZIFs) with a loading efficiency of 17% and enhanced endosomal escape promoted by the protonated imidazole moieties. The gene editing potential of CRISPR/Cas9 encapsulated by ZIF-8 (CC-ZIFs) is further verified by knocking down the gene expression of green fluorescent protein by 37% over 4 days. The nanoscale CC-ZIFs are biocompatible and easily scaled-up offering excellent loading capacity and controlled codelivery of intact Cas9 protein and sgRNA.


Assuntos
Sistemas CRISPR-Cas/fisiologia , Endossomos/metabolismo , Edição de Genes , Imidazóis/química , Nanopartículas/química , Zeolitas/química , Animais , Células CHO , Cricetulus , Tamanho da Partícula
8.
Chem Pharm Bull (Tokyo) ; 66(8): 773-778, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30068796

RESUMO

The ability of tumors to escape from immune destruction is attributed to the protein-protein interaction between programmed cell death protein 1 (PD1) and programmed cell death ligand 1 (PDL1) proteins expressed by immune T cells and cancer cells, respectively. Therefore, pharmacological inhibition of the PD1-PDL1 interaction presents an important therapeutic target against a variety of tumors expressing PDL1 on their cell surface. Recently, five antibodies have been approved and several are in clinical trials against the PD1-PDL1 protein-protein interaction target. In contrast, there are very few reports of small-molecule inhibitors of PD1-PDL1 interaction, and most of them have relatively modest or weak inhibition activities, emphasizing the difficulty in designing small-molecule inhibitors against this challenging target. Therefore, we focused our attention on macrocycles that are known to exhibit target activity comparable to large macromolecules despite having molecular weights closer to small, drug-like molecules. In this context, our present study led to the identification of several macrocyclic compounds from the ansamycin antibiotics class to be inhibitors of PD1-PDL1 interaction. Importantly, one of these macrocyclic antibiotics, Rifabutin, showed an IC50 value of ca. 25 µM. This is remarkable considering it has a relatively low molecular weight and still is capable of inhibiting PD1-PDL1 protein-protein interaction whose binding interface spans over ca. 1970 Å2. Thus, these macrocycles may serve as guiding points for discovery and optimization of more potent, selective small-molecule inhibitors of PD1-PDL1 interaction, one of the most promising therapeutic targets against cancer.


Assuntos
Antibacterianos/química , Antineoplásicos/química , Antígeno B7-H1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Rifabutina/análogos & derivados , Rifabutina/química , Antígeno B7-H1/química , Descoberta de Drogas , Humanos , Modelos Moleculares , Receptor de Morte Celular Programada 1/química , Ligação Proteica
9.
J Am Chem Soc ; 139(30): 10232-10238, 2017 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-27775320

RESUMO

Toroidal structures based on self-assembly of predesigned building blocks are well-established in the literature, but spontaneous self-organization to prepare such structures has not been reported to date. Here, organic-inorganic hybrid microtoroids synthesized by simultaneous coordination-driven assembly of amphiphilic molecules and hydrophilic polymers are reported. Mixing amphiphilic molecules with iron(III) chloride and hydrophilic polymers in water leads, within minutes, to the formation of starlike nanostructures. A spontaneous self-organization of these nanostructures is then triggered to form stable hybrid microtoroids. Interestingly, the toroids exhibit anisotropic hierarchical growth, giving rise to a layered toroidal framework. These microstructures are mechanically robust and can act as templates to host metallic nanoparticles such as gold and silver. Understanding the nature of spontaneous assembly driven by coordination multiple non-covalent interactions can help explain the well-ordered complexity of many biological organisms in addition to expanding the available tools to mimic such structures at a molecular level.

10.
Chemistry ; 22(39): 13789-13793, 2016 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-27356263

RESUMO

Supramolecular self-assembly of histidine-capped-dialkoxy-anthracene (HDA) results in the formation of light-responsive nanostructures. Single-crystal X-ray diffraction analysis of HDA shows two types of hydrogen bonding. The first hydrogen bond is established between the imidazole moieties while the second involves the oxygen atom of one amide group and the hydrogen atom of a second amide group. When protonated in acidic aqueous media, HDA successfully complexes siRNA yielding spherical nanostructures. This biocompatible platform controllably delivers siRNA with high efficacy upon visible-light irradiation leading up to 90 % of gene silencing in live cells.


Assuntos
Antracenos/química , Técnicas de Transferência de Genes , Histidina/análogos & derivados , Interferência de RNA , RNA Interferente Pequeno/administração & dosagem , Cristalografia por Raios X , Células HeLa , Humanos , Ligação de Hidrogênio , Luz , Modelos Moleculares , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Interferente Pequeno/genética
11.
Soft Matter ; 12(11): 2842-5, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-26908051

RESUMO

The supramolecular assembly of anionic azobenzene dicarboxylate and cationic cetyltrimethylammonium bromide (CTAB) formed a stimuli responsive hydrogel with a critical gelation concentration (CGC) of 0.33 wt%. This self-sustainable two-component system was able to repair damage upon light irradiation. Moreover, it was successfully employed in the fabrication of highly sensitive humidity sensors for the first time.

12.
Biochem Biophys Res Commun ; 464(2): 647-53, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26168735

RESUMO

Treg cells are not only crucial for controlling immune responses to autoantigens but also prevent those directed towards commensal pathogens. Control of effector immune responses by Treg cells depend on their capacity to accumulate at inflammatory site and accordingly accommodate to inflammatory environment. Till date, the factors associated with maintaining these aspects of Treg phenotype is not understood properly. Here we have shown that a known nuclear matrix binding protein SMAR1 is selectively expressed more in colonic Treg cells and is required for their ability to accumulate at inflammatory site and to sustain high levels of Foxp3 and IL-10 expression during acute colitis. Elimination of anti-inflammatory subsets revealed a protective role for IL-10 producing Treg cells in SMAR1(-/-) mice. Moreover, a combined action of Foxp3 and SMAR1 restricts effector cytokine production and enhance the production of IL-10 by colonic Treg cells that controls acute colitis. This data highlights a critical role of SMAR1 in maintaining Treg physiology during inflammatory disorders.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Colite/imunologia , Proteínas de Ligação a DNA/fisiologia , Interleucina-10/fisiologia , Proteínas Nucleares/fisiologia , Linfócitos T Reguladores/imunologia , Doença Aguda , Animais , Proteínas de Ciclo Celular/genética , Diferenciação Celular , Proteínas de Ligação a DNA/genética , Camundongos , Camundongos Knockout , Proteínas Nucleares/genética , Linfócitos T Reguladores/patologia
13.
J Comput Aided Mol Des ; 29(2): 155-63, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25377899

RESUMO

The inhibition of tumor suppressor p53 protein due to its direct interaction with oncogenic murine double minute 2 (MDM2) protein, plays a central role in almost 50 % of all human tumor cells. Therefore, pharmacological inhibition of the p53-binding pocket on MDM2, leading to p53 activation, presents an important therapeutic target against these cancers expressing wild-type p53. In this context, the present study utilized an integrated virtual and experimental screening approach to screen a database of approved drugs for potential p53-MDM2 interaction inhibitors. Specifically, using an ensemble rigid-receptor docking approach with four MDM2 protein crystal structures, six drug molecules were identified as possible p53-MDM2 inhibitors. These drug molecules were then subjected to further molecular modeling investigation through flexible-receptor docking followed by Prime/MM-GBSA binding energy analysis. These studies identified fluspirilene, an approved antipsychotic drug, as a top hit with MDM2 binding mode and energy similar to that of a native MDM2 crystal ligand. The molecular dynamics simulations suggested stable binding of fluspirilene to the p53-binding pocket on MDM2 protein. The experimental testing of fluspirilene showed significant growth inhibition of human colon tumor cells in a p53-dependent manner. Fluspirilene also inhibited growth of several other human tumor cell lines in the NCI60 cell line panel. Taken together, these computational and experimental data suggest a potentially novel role of fluspirilene in inhibiting the p53-MDM2 interaction. It is noteworthy here that fluspirilene has a long history of safe human use, thus presenting immediate clinical potential as a cancer therapeutic. Furthermore, fluspirilene could also serve as a structurally-novel lead molecule for the development of more potent, small-molecule p53-MDM2 inhibitors against several types of cancer. Importantly, the combined computational and experimental screening protocol presented in this study may also prove useful for screening other commercially-available compound databases for identification of novel, small molecule p53-MDM2 inhibitors.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Fluspirileno/química , Proteínas Proto-Oncogênicas c-mdm2/química , Proteína Supressora de Tumor p53/química , Animais , Neoplasias do Colo/patologia , Cristalografia por Raios X , Fluspirileno/uso terapêutico , Humanos , Camundongos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteína Supressora de Tumor p53/antagonistas & inibidores
14.
IEEE Trans Robot ; 31(1): 104-116, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26279645

RESUMO

As sampling-based motion planners become faster, they can be re-executed more frequently by a robot during task execution to react to uncertainty in robot motion, obstacle motion, sensing noise, and uncertainty in the robot's kinematic model. We investigate and analyze high-frequency replanning (HFR), where, during each period, fast sampling-based motion planners are executed in parallel as the robot simultaneously executes the first action of the best motion plan from the previous period. We consider discrete-time systems with stochastic nonlinear (but linearizable) dynamics and observation models with noise drawn from zero mean Gaussian distributions. The objective is to maximize the probability of success (i.e., avoid collision with obstacles and reach the goal) or to minimize path length subject to a lower bound on the probability of success. We show that, as parallel computation power increases, HFR offers asymptotic optimality for these objectives during each period for goal-oriented problems. We then demonstrate the effectiveness of HFR for holonomic and nonholonomic robots including car-like vehicles and steerable medical needles.

15.
J Assoc Physicians India ; 63(7): 67-70, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26731834

RESUMO

A young male admitted for dengue fever and systemic involvement developed ECG abnormalities on third day, in the form of prolonged QT interval and deep and symmetrical inversion of T wave. Echocardiography revealed akinesia of mid and apical segments and well contracting basal segments, typical of Takotsubo cardiomyopathy or stress cardiomyopathy. These changes were transient and echocardiography findings reverted to normal kinesis of left ventricle without any treatment or without any residual left ventricle dysfunction.


Assuntos
Dengue/complicações , Cardiomiopatia de Takotsubo/diagnóstico , Cardiomiopatia de Takotsubo/etiologia , Criança , Humanos , Masculino
16.
Bioconjug Chem ; 25(8): 1517-25, 2014 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-25036457

RESUMO

This paper describes the synthesis, characterization, and in vitro and in vivo siRNA transfection ability of B vitamin-based cationic clickable bolaamphiphiles (VBs). Our VBs derived from vitamins B2, B3, B5, B6, and B7 formed nanoassembled low-molecular-weight hydrogelators (LMWGs, vitagels). The vitagels VB2, VB6, and VB7 (derived from vitamins B2, B6, and B7, respectively) facilitated delivery of small interfering RNAs (siRNA), efficiently silencing gene expression specifically into cancer cell lines; in addition, the LMWGs derived from vitamins B3, B5, and B6 were biocompatible. An ex vivo study in a mouse model revealed that the siRNA delivered by the vitagel VB7 was located primarily at the site of the tumor. The gene silencing efficiency of vascular endothelial growth factor siRNA delivered by vitagels was dependent on the nature of the vitamin headgroup, the N/P ratio, and, interestingly, the hydrogelation properties of the VBs.


Assuntos
Portadores de Fármacos/química , Inativação Gênica , Hidrogéis/química , Nanoestruturas/química , RNA Interferente Pequeno/genética , Transfecção/métodos , Complexo Vitamínico B/química , Animais , Sequência de Bases , Transporte Biológico , Linhagem Celular Tumoral , Química Click , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Peso Molecular , RNA Interferente Pequeno/química , RNA Interferente Pequeno/metabolismo
17.
J Comput Aided Mol Des ; 28(2): 89-97, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24554192

RESUMO

The p53 protein, known as the guardian of genome, is mutated or deleted in approximately 50 % of human tumors. In the rest of the cancers, p53 is expressed in its wild-type form, but its function is inhibited by direct binding with the murine double minute 2 (MDM2) protein. Therefore, inhibition of the p53-MDM2 interaction, leading to the activation of tumor suppressor p53 protein presents a fundamentally novel therapeutic strategy against several types of cancers. The present study utilized ultrafast shape recognition (USR), a virtual screening technique based on ligand-receptor 3D shape complementarity, to screen DrugBank database for novel p53-MDM2 inhibitors. Specifically, using 3D shape of one of the most potent crystal ligands of MDM2, MI-63, as the query molecule, six compounds were identified as potential p53-MDM2 inhibitors. These six USR hits were then subjected to molecular modeling investigations through flexible receptor docking followed by comparative binding energy analysis. These studies suggested a potential role of the USR-selected molecules as p53-MDM2 inhibitors. This was further supported by experimental tests showing that the treatment of human colon tumor cells with the top USR hit, telmisartan, led to a dose-dependent cell growth inhibition in a p53-dependent manner. It is noteworthy that telmisartan has a long history of safe human use as an approved anti-hypertension drug and thus may present an immediate clinical potential as a cancer therapeutic. Furthermore, it could also serve as a structurally-novel lead molecule for the development of more potent, small-molecule p53-MDM2 inhibitors against variety of cancers. Importantly, the present study demonstrates that the adopted USR-based virtual screening protocol is a useful tool for hit identification in the domain of small molecule p53-MDM2 inhibitors.


Assuntos
Ensaios de Seleção de Medicamentos Antitumorais/métodos , Processamento de Imagem Assistida por Computador/métodos , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteína Supressora de Tumor p53/antagonistas & inibidores , Benzimidazóis/química , Benzimidazóis/farmacologia , Benzoatos/química , Benzoatos/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Bases de Dados Factuais , Relação Dose-Resposta a Droga , Humanos , Imidazóis/química , Imidazóis/farmacologia , Ligantes , Modelos Moleculares , Simulação de Acoplamento Molecular , Piperazinas/química , Piperazinas/farmacologia , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-mdm2/química , Telmisartan , Proteína Supressora de Tumor p53/química
18.
IEEE Trans Robot ; 30(4): 853-864, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25435829

RESUMO

Steerable needles have the potential to improve the effectiveness of needle-based clinical procedures such as biopsy and drug delivery by improving targeting accuracy and reaching previously inaccessible targets that are behind sensitive or impenetrable anatomical regions. We present a new needle steering system capable of automatically reaching targets in 3-D environments while avoiding obstacles and compensating for real-world uncertainties. Given a specification of anatomical obstacles and a clinical target (e.g., from preoperative medical images), our system plans and controls needle motion in a closed-loop fashion under sensory feedback to optimize a clinical metric. We unify planning and control using a new fast algorithm that continuously replans the needle motion. Our rapid replanning approach is enabled by an efficient sampling-based rapidly exploring random tree (RRT) planner that achieves orders-of-magnitude reduction in computation time compared with prior 3-D approaches by incorporating variable curvature kinematics and a novel distance metric for planning. Our system uses an electromagnetic tracking system to sense the state of the needle tip during the procedure. We experimentally evaluate our needle steering system using tissue phantoms and animal tissue ex vivo. We demonstrate that our rapid replanning strategy successfully guides the needle around obstacles to desired 3-D targets with an average error of less than 3 mm.

19.
Int J Rob Res ; 33(10): 1361-1374, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26279600

RESUMO

Needle insertion is commonly performed in minimally invasive medical procedures such as biopsy and radiation cancer treatment. During such procedures, accurate needle tip placement is critical for correct diagnosis or successful treatment. Accurate placement of the needle tip inside tissue is challenging, especially when the target moves and anatomical obstacles must be avoided. We develop a needle steering system capable of autonomously and accurately guiding a steerable needle using two-dimensional (2D) ultrasound images. The needle is steered to a moving target while avoiding moving obstacles in a three-dimensional (3D) non-static environment. Using a 2D ultrasound imaging device, our system accurately tracks the needle tip motion in 3D space in order to estimate the tip pose. The needle tip pose is used by a rapidly exploring random tree-based motion planner to compute a feasible needle path to the target. The motion planner is sufficiently fast such that replanning can be performed repeatedly in a closed-loop manner. This enables the system to correct for perturbations in needle motion, and movement in obstacle and target locations. Our needle steering experiments in a soft-tissue phantom achieves maximum targeting errors of 0.86 ± 0.35 mm (without obstacles) and 2.16 ± 0.88 mm (with a moving obstacle).

20.
Pharmaceuticals (Basel) ; 17(4)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38675451

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by pathophysiological deposits of extracellular amyloid beta (Aß) peptides and intracellular neurofibrillary tangles of tau. The central role of Aß in AD pathology is well-established, with its increased deposition attributed mainly to its decreased cerebral clearance. Here, it is noteworthy that apolipoprotein E (ApoE), the most significant risk factor for AD, has been shown to play an isoform-specific role in clearing Aß deposits (ApoE2 > ApoE3 > ApoE4), owing mainly to its lipidation status. In addition to the pathophysiological Aß deposits, AD is also characterized by abnormal glucose metabolism, which is a distinct event preceding Aß deposition. The present study established, for the first time, a possible link between these two major AD etiologies, with glucose metabolism directly influencing ApoE lipidation and its secretion by astrocytes expressing human ApoE4. Specifically, glucose dose-dependently activated liver X receptor (LXR), leading to elevated ABCA1 and ABCG1 protein levels and enhanced ApoE lipidation. Moreover, co-treatment with a glycolytic inhibitor significantly inhibited this LXR activation and subsequent ApoE lipidation, further supporting a central role of glucose metabolism in LXR activation leading to enhanced ApoE lipidation, which may help against AD through potential Aß clearance. Therefore, we hypothesized that pharmacological agents that can target cellular energy metabolism, specifically aerobic glycolysis, may hold significant therapeutic potential against AD. In this context, the present study also led to the discovery of novel, small-molecule stimulants of astrocytic glucose metabolism, leading to significantly enhanced lipidation status of ApoE4 in astrocytic cells. Three such newly discovered compounds (lonidamine, phenformin, and berberine), owing to their promising cellular effect on the glycolysis-ApoE nexus, warrant further investigation in suitable in vivo models of AD.

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