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1.
Cells ; 12(13)2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37443709

RESUMO

Oral cancer patients suffer pain at the site of the cancer. Calcitonin gene related polypeptide (CGRP), a neuropeptide expressed by a subset of primary afferent neurons, promotes oral cancer growth. CGRP also mediates trigeminal pain (migraine) and neurogenic inflammation. The contribution of CGRP to oral cancer pain is investigated in the present study. The findings demonstrate that CGRP-immunoreactive (-ir) neurons and neurites innervate orthotopic oral cancer xenograft tumors in mice. Cancer increases anterograde transport of CGRP in axons innervating the tumor, supporting neurogenic secretion as the source of CGRP in the oral cancer microenvironment. CGRP antagonism reverses oral cancer nociception in preclinical oral cancer pain models. Single-cell RNA-sequencing is used to identify cell types in the cancer microenvironment expressing the CGRP receptor components, receptor activity modifying protein 1 Ramp1 and calcitonin receptor like receptor (CLR, encoded by Calcrl). Ramp1 and Calcrl transcripts are detected in cells expressing marker genes for Schwann cells, endothelial cells, fibroblasts and immune cells. Ramp1 and Calcrl transcripts are more frequently detected in cells expressing fibroblast and immune cell markers. This work identifies CGRP as mediator of oral cancer pain and suggests the antagonism of CGRP to alleviate oral cancer pain.


Assuntos
Dor do Câncer , Neoplasias Bucais , Hormônios Peptídicos , Humanos , Camundongos , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Calcitonina , Pró-Calcitonina , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/genética , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , Dor do Câncer/tratamento farmacológico , Células Endoteliais/metabolismo , Neoplasias Bucais/tratamento farmacológico , Microambiente Tumoral
2.
Chem Commun (Camb) ; 54(68): 9438-9441, 2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30079426

RESUMO

A novel, one-step method for the synthesis of functional, organic-inorganic hybrid nanoparticles is reported. The quench ionic Flash NanoPrecipitation (qiFNP) method enables the straightforward synthesis of nanoparticles by decoupling the formation of the inorganic core and surface functionalization. As a proof-of-concept, the qiFNP method was successfully applied for the tunable and highly controlled synthesis of various LnPO4-based nanomaterials for bioimaging applications.

3.
Adv Healthc Mater ; 4(9): 1376-85, 2015 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-25925128

RESUMO

Magnetic resonance imaging (MRI)- and near-infrared (NIR)-active, multimodal composite nanocarriers (CNCs) are prepared using a simple one-step process, flash nanoprecipitation (FNP). The FNP process allows for the independent control of the hydrodynamic diameter, co-core excipient and NIR dye loading, and iron oxide-based nanocrystal (IONC) content of the CNCs. In the controlled precipitation process, 10 nm IONCs are encapsulated into poly(ethylene glycol) (PEG) stabilized CNCs to make biocompatible T2 contrast agents. By adjusting the formulation, CNC size is tuned between 80 and 360 nm. Holding the CNC size constant at an intensity weighted average diameter of 99 ± 3 nm (PDI width 28 nm), the particle relaxivity varies linearly with encapsulated IONC content ranging from 66 to 533 × 10(-3) m(-1) s(-1) for CNCs formulated with 4-16 wt% IONC. To demonstrate the use of CNCs as in vivo MRI contrast agents, CNCs are surface functionalized with liver-targeting hydroxyl groups. The CNCs enable the detection of 0.8 mm(3) non-small cell lung cancer metastases in mice livers via MRI. Incorporating the hydrophobic, NIR dye tris-(porphyrinato)zinc(II) into CNCs enables complementary visualization with long-wavelength fluorescence at 800 nm. In vivo imaging demonstrates the ability of CNCs to act both as MRI and fluorescent imaging agents.


Assuntos
Meios de Contraste , Portadores de Fármacos , Compostos Férricos , Imageamento por Ressonância Magnética/métodos , Nanopartículas/química , Imagem Óptica/métodos , Animais , Meios de Contraste/química , Meios de Contraste/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Compostos Férricos/química , Compostos Férricos/farmacologia , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Camundongos , Tamanho da Partícula , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia
4.
Biomacromolecules ; 15(1): 252-61, 2014 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-24410445

RESUMO

The formation of 10-40 µm composite gel microparticles (CGMPs) comprised of ∼100 nm drug containing nanoparticles (NPs) in a poly(ethylene glycol) (PEG) gel matrix is described. The CGMP particles enable targeting to the lung by filtration from the venous circulation. UV radical polymerization and Michael addition polymerization reactions are compared as approaches to form the PEG matrix. A fluorescent dye in the solid core of the NP was used to investigate the effect of reaction chemistry on the integrity of encapsulated species. When formed via UV radical polymerization, the fluorescence signal from the NPs indicated degradation of the encapsulated species by radical attack. The degradation decreased fluorescence by 90% over 15 min of UV exposure. When formed via Michael addition polymerization, the fluorescence was maintained. Emulsion processing using controlled shear stress enabled control of droplet size with narrow polydispersity. To allow for emulsion processing, the gelation rate was delayed by adjusting the solution pH. At a pH = 5.4, the gelation occurred at 3.5 h. The modulus of the gels was tuned over the range of 5 to 50 kPa by changing the polymer concentration between 20 and 70 vol %. NP aggregation during polymerization, driven by depletion forces, was controlled by the reaction kinetics. The ester bonds in the gel network enabled CGMP degradation. The gel modulus decreased by 50% over 27 days, followed by complete gel degradation after 55 days. This permits ultimate clearance of the CGMPs from the lungs. The demonstration of uniform delivery of 15.8 ± 2.6 µm CGMPs to the lungs of mice, with no deposition in other organs, is shown, and indicates the ability to concentrate therapeutics in the lung while avoiding off-target toxic exposure.


Assuntos
Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Géis/química , Pulmão/química , Nanopartículas/química , Imagem Óptica/métodos , Animais , Géis/administração & dosagem , Géis/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Camundongos , Nanopartículas/administração & dosagem
5.
Mol Pharm ; 10(1): 319-28, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23259920

RESUMO

We present an in situ hydrophobic salt forming technique for the encapsulation of weakly hydrophobic, ionizable active pharmaceutical ingredients (API) into stable nanocarriers (NCs) formed via a rapid precipitation process. Traditionally, NC formation via rapid precipitation has been difficult with APIs in this class because their intermediate solubility makes achieving high supersaturation difficult during the precipitation process and the intermediate solubility causes rapid Ostwald ripening or recrystallization after precipitation. By forming a hydrophobic salt in situ, the API solubility and crystallinity can be tuned to allow for NC formation. Unlike covalent API modification, the hydrophobic salt formation modifies properties via ionic interactions, thus circumventing the need for full FDA reapproval. This technique greatly expands the types of APIs that can be successfully encapsulated in NC form. Three model APIs were investigated and successfully incorporated into NCs by forming salts with hydrophobic counterions: cinnarizine, an antihistamine, clozapine, an antipsychotic, and α-lipoic acid, a common food supplement. We focus on cinnarizine to develop the rules for the in situ nanoprecipitation of salt NCs. These rules include the pK(a)s and solubilities of the API and counterion, the effect of the salt former-to-API ratio on particle stability and encapsulation efficiency, and the control of NC size. Finally, we present results on the release rates of these ion pair APIs from the NCs.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Polímeros/química , Precipitação Química , Cinarizina/química , Clozapina/química , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Íons/química , Naftóis/química , Tamanho da Partícula , Sais/química , Solubilidade , Ácido Tióctico/química
6.
Acta Crystallogr C ; 64(Pt 4): m147-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18391373

RESUMO

The tricarbonylchromium unit bound to the arene ring of the chiral title complex, [Cr(C(19)H(26)O(3))(CO)(3)], is rotated by ca 25 degrees in agreement with the proposed mechanism for 1,5-asymmetric induction of nucleophilic attack.


Assuntos
Compostos Bicíclicos com Pontes/química , Compostos de Cromo/química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular
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