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1.
Heliyon ; 9(11): e22081, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38034801

RESUMEN

Polarimetric imaging systems combining machine learning is emerging as a promising tool for the support of diagnosis and intervention decision-making processes in cancer detection/staging. A present study proposes a novel method based on Mueller matrix imaging combining optical parameters and machine learning models for classifying the progression of skin cancer based on the identification of three different types of mice skin tissues: healthy, papilloma, and squamous cell carcinoma. Three different machine learning algorithms (K-Nearest Neighbors, Decision Tree, and Support Vector Machine (SVM)) are used to construct a classification model using a dataset consisting of Mueller matrix images and optical properties extracted from the tissue samples. The experimental results show that the SVM model is robust to discriminate among three classes in the training stage and achieves an accuracy of 94 % on the testing dataset. Overall, it is provided that polarimetric imaging systems and machine learning algorithms can dynamically combine for the reliable diagnosis of skin cancer.

2.
Z Naturforsch C J Biosci ; 78(5-6): 247-251, 2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-36544263

RESUMEN

From the CHCl3-soluble extract of Annona muricata L. (Annonaceae) leaves, one new 3-benzazepine-type alkaloid, anonazepine (1), and four known aporphine-type alkaloids, (+)-laurotetanine (2), (+)-norglaucine (3), (-)-xylopine (4), and lanuginosine (5), were isolated. Except for (-)-xylopine (4), these remaining known alkaloids were first reported in A. muricata. The structures of the isolated alkaloids were established by 1D and 2D NMR spectroscopy and MS, as well as comparison with literature data. The new 3-benzazepine-type alkaloid existed in an inseparable mixture of two equilibrium conformers. Its absolute configuration was determined based on comparing their experimental and calculated ECD data. The anti-inflammatory activity of the isolated alkaloids was investigated, but none of the alkaloids showed a significant result.


Asunto(s)
Alcaloides , Annona , Annonaceae , Antineoplásicos , Annona/química , Alcaloides/farmacología , Alcaloides/química , Extractos Vegetales/farmacología , Extractos Vegetales/química
3.
J Biomed Opt ; 27(7): 075002, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-36451700

RESUMEN

Significance: The combination of polarized imaging with artificial intelligence (AI) technology has provided a powerful tool for performing an objective and precise diagnosis in medicine. Aim: An approach is proposed for the detection of hepatitis B (HB) virus using a combined Mueller matrix imaging technique and deep learning method. Approach: In the proposed approach, Mueller matrix imaging polarimetry is applied to obtain 4 × 4 Mueller matrix images of 138 HBsAg-containing (positive) serum samples and 136 HBsAg-free (negative) serum samples. The kernel estimation density results show that, of the 16 Mueller matrix elements, elements M 22 and M 33 provide the best discriminatory power between the positive and negative samples. Results: As a result, M 22 and M 33 are taken as the inputs to five different deep learning models: Xception, VGG16, VGG19, ResNet 50, and ResNet150. It is shown that the optimal classification accuracy (94.5%) is obtained using the VGG19 model with element M 22 as the input. Conclusions: Overall, the results confirm that the proposed hybrid Mueller matrix imaging and AI framework provides a simple and effective approach for HB virus detection.


Asunto(s)
Inteligencia Artificial , Hepatitis B , Humanos , Hepatitis B/diagnóstico por imagen , Diagnóstico por Imagen
4.
Pharm Res ; 28(12): 3189-98, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21691892

RESUMEN

PURPOSE: To study a passive targeting strategy, via the enhanced permeability and retention effect following systemic administration of lipid nanocapsules (LNCs) loaded with ferrociphenol, FcdiOH. METHODS: Long chains of polyethylene glycol (DSPE-mPEG2000) were incorporated onto the surface of LNCs by post-insertion technique. Stealth properties of LNCs were investigated by in vitro complement consumption and macrophage uptake, and in vivo pharmacokinetics in healthy rats. Antitumour effect of FcdiOH-loaded LNCs was evaluated in subcutaneous and intracranial 9L gliosarcoma rat models. RESULTS: LNCs and DSPE-mPEG2000-LNCs presented low complement activation and weak macrophage uptake. DSPE-mPEG2000-LNCs exhibited prolonged half-life and extended area under the curve in healthy rats. In a subcutaneous gliosarcoma model, a single intravenous injection of FcdiOH-LNCs (400 µL, 2.4 mg/rat) considerably inhibited tumour growth when compared to the control. DSPE-mPEG2000-FcdiOH-LNCs exhibited a strong antitumour effect by nearly eradicating the tumour by the end of the study. In intracranial gliosarcoma model, treatment with DSPE-mPEG2000-FcdiOH-LNCs and FcdiOH-LNCs statistically improved median survival time (28 and 27.5 days, respectively) compared to the control (25 days). CONCLUSION: These results demonstrate the interesting perspectives for the systemic treatment of glioma thanks to bio-organometallic chemotherapy via lipid nanocapsules.


Asunto(s)
Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Compuestos Ferrosos/administración & dosificación , Compuestos Ferrosos/uso terapéutico , Gliosarcoma/tratamiento farmacológico , Nanocápsulas/química , Animales , Encéfalo/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Femenino , Lípidos/química , Polietilenglicoles/química , Ratas , Ratas Endogámicas F344
5.
Int J Pharm ; 423(1): 63-8, 2012 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-21554935

RESUMEN

The prognosis of patients with malignant glioma remains extremely poor despite surgery and improvements in radio- and chemo-therapies. Thus, treatment strategies that specifically target these tumors have the potential to greatly improve therapeutic outcomes. "Marrow-isolated adult multilineage inducible" cells (MIAMI cells) are a subpopulation of mesenchymal stromal cells (MSCs) which possess the ability to migrate to brain tumors. We have previously shown that MIAMI cells were able to efficiently incorporate lipid nanocapsules (LNCs) without altering either their stem cell properties or their migration capacity. In this study, we assessed whether the cytotoxic effects of MIAMI cells loaded with LNCs containing an organometallic complex (ferrociphenol or Fc-diOH) could be used to treat brain tumors. The results showed that MIAMI cells internalized Fc-diOH-LNCs and that this internalization did not induce MIAMI cell death. Furthermore, Fc-diOH-LNC-loaded MIAMI cells produced a cytotoxic effect on U87MG glioma cells in vitro. This cytotoxic effect was validated in vivo after intratumoral injection of Fc-diOH-LNC-loaded MIAMI cells in a heterotopic U87MG glioma model in nude mice. These promising results open up a new field of treatment in which cellular vehicles and nanoparticles can be combined to treat brain tumors.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Sistemas de Liberación de Medicamentos/métodos , Compuestos Ferrosos/administración & dosificación , Compuestos Ferrosos/uso terapéutico , Lípidos/química , Trasplante de Células Madre Mesenquimatosas , Nanocápsulas/química , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Técnicas de Cocultivo , Cumarinas/administración & dosificación , Cumarinas/metabolismo , Femenino , Compuestos Ferrosos/farmacología , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Humanos , Inyecciones Intralesiones , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Desnudos , Tamaño de la Partícula , Lectinas de Plantas/química , Polietilenglicoles/química , Proteínas de Soja/química , Electricidad Estática , Ácidos Esteáricos/química , Tiazoles/administración & dosificación , Tiazoles/metabolismo , Resultado del Tratamiento , Triglicéridos/química , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Eur J Pharm Biopharm ; 81(3): 690-3, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22561953

RESUMEN

In this study, a new active targeting strategy to favour ferrociphenol (FcdiOH) internalisation into brain tumour cells was developed by the use of lipid nanocapsules (LNCs) coated with a cell-internalising peptide (NFL-TBS.40-63 peptide) that interacts with tubulin-binding sites. In comparison, OX26 murine monoclonal antibodies (OX26-MAb) targeting transferrin receptors were also inserted onto the LNC surface. The incorporation of OX26 or peptide did not influence the in vitro antiproliferative effect of FcdiOH-LNCs on the 9L cells since their IC50 values were found in the same range. In vivo, intracerebral administration of OX26-FcdiOH-LNCs or peptide-FcdiOH-LNCs by convection enhanced delivery did not enhance the animal median survival time in comparison with untreated rats (25 days). Interestingly, intra-carotid treatment with peptide-FcdiOH-LNCs led to an ameliorated survival time of treated rats with the presence of animals surviving until days 35, 40 and 44. Such results were not obtained with OX26-MAbs, demonstrating the benefit of NFL-TBS.40-63 peptide as an active ligand for peripheral drug delivery to the brain tumours.


Asunto(s)
Antineoplásicos/administración & dosificación , Neoplasias Encefálicas/tratamiento farmacológico , Sistemas de Liberación de Medicamentos , Compuestos Ferrosos/administración & dosificación , Gliosarcoma/tratamiento farmacológico , Animales , Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Anticuerpos Monoclonales de Origen Murino/farmacología , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Sitios de Unión , Neoplasias Encefálicas/patología , Proliferación Celular/efectos de los fármacos , Femenino , Compuestos Ferrosos/farmacocinética , Compuestos Ferrosos/farmacología , Gliosarcoma/patología , Concentración 50 Inhibidora , Lípidos/química , Nanocápsulas , Proteínas de Neurofilamentos/química , Fragmentos de Péptidos/química , Ratas , Ratas Endogámicas F344 , Receptores de Transferrina/inmunología , Tasa de Supervivencia , Tubulina (Proteína)/metabolismo
7.
Int J Pharm ; 423(1): 55-62, 2012 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-21536115

RESUMEN

The anti-tumour effect of ferrociphenol (FcdiOH)-loaded lipid nanocapsules (LNCs), with or without a DSPE-mPEG2000 coating, was evaluated on an orthotopic gliosarcoma model after administration by convection-enhanced delivery (CED) technique or by intra-carotid injection. No toxicity was observed by MRI nor by MRS in healthy rats receiving a CED injection of FcdiOH-LNCs (60µL, 0.36mg of FcdiOH/rat) when the pH and osmolarity had been adjusted to physiological values prior to injection. At this dose, the treatment by CED with FcdiOH-LNCs significantly increased the survival time of tumour-bearing rats in comparison with an untreated group (28.5 days vs 25 days, P=0.0009) whereas DSPE-mPEG2000-FcdiOH-LNCs did not exhibit any efficacy with a median survival time of 24 days. After intra-carotid injection (400µL, 2.4mg of FcdiOH/rat), hyperosmolar DSPE-mPEG2000-FcdiOH-LNCs markedly increased the median survival time (up to 30 days, P=0.0008) as compared to the control (20%). This was strengthened by their evidenced accumulation in the tumour zone and by the measure of the fluorescent brain surface obtained on brain slides for these DiI-labelled LNCs, being 3-fold higher than for the control. These results demonstrated that, depending upon the administration route used, the characteristics of LNC suspensions had to be carefully adapted.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Compuestos Ferrosos/administración & dosificación , Compuestos Ferrosos/uso terapéutico , Gliosarcoma/tratamiento farmacológico , Lípidos/química , Nanocápsulas/química , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Encéfalo/metabolismo , Encéfalo/patología , Neoplasias Encefálicas/patología , Portadores de Fármacos/química , Portadores de Fármacos/toxicidad , Femenino , Colorantes Fluorescentes/administración & dosificación , Colorantes Fluorescentes/metabolismo , Gliosarcoma/patología , Concentración de Iones de Hidrógeno , Infusiones Parenterales/métodos , Inyecciones Intraarteriales , Estimación de Kaplan-Meier , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Nanocápsulas/toxicidad , Concentración Osmolar , Tamaño de la Partícula , Fosfatidiletanolaminas/química , Lectinas de Plantas/química , Polietilenglicoles/química , Ratas , Ratas Endogámicas F344 , Proteínas de Soja/química , Electricidad Estática , Ácidos Esteáricos/química , Resultado del Tratamiento , Triglicéridos/química
8.
Int J Pharm ; 426(1-2): 231-238, 2012 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-22306040

RESUMEN

The paper describes sterically stabilized lipid nanocapsules (LNC) and multilamellar liposomes (MLV) coated using a new amphiphilic conjugate of PEG(2000) with a 2-alkyl-lipoamino acid (LAA). A complement activation assay (CH50) and uptake experiments by THP-1 macrophage cells were used to assess in vitro the effectiveness of the PEG-LAA derivative of modifying the surface behavior of nanocarriers. Administered to rats or Swiss mice, respectively, the PEG(2000)-LAA-modified LNC and MLV showed plasma half-lives longer than the corresponding naked carriers. To assess the ability of nanocarriers to specifically reach tumor sites, paclitaxel (PTX)-loaded LNC and MLV were administered subcutaneously to rats implanted with a 9L glioma. Animals treated with saline or naked LNC and MLV underwent a quick expansion of tumor mass, up to a volume of 2000 mm(3) 25 days after the injection of tumor cells. On the contrary, treatment with a PEG-LAA modified LNC carrier reduced the growth of the tumor volume, which did not exceed 1000 mm(3) by day 25. Analogous positive results were obtained with the liposomal systems. The experimental findings confirmed that these new PEG-LAA conjugates allow to obtain sterically stable nanocarriers that behave effectively and in a comparable or even better way than the (phospho)lipid PEG derivatives commercially available.


Asunto(s)
Antineoplásicos Fitogénicos/farmacocinética , Portadores de Fármacos , Paclitaxel/farmacocinética , Polietilenglicoles/química , Tensoactivos/química , Animales , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/sangre , Antineoplásicos Fitogénicos/química , Línea Celular Tumoral , Química Farmacéutica , Coloides , Ensayo de Actividad Hemolítica de Complemento , Composición de Medicamentos , Gliosarcoma/metabolismo , Gliosarcoma/patología , Semivida , Humanos , Inyecciones Intravenosas , Liposomas , Macrófagos/metabolismo , Ratones , Nanocápsulas , Nanotecnología , Paclitaxel/administración & dosificación , Paclitaxel/sangre , Paclitaxel/química , Ratas , Ratas Endogámicas F344 , Ratas Wistar , Propiedades de Superficie , Tecnología Farmacéutica/métodos , Distribución Tisular , Carga Tumoral/efectos de los fármacos
9.
Nanomedicine (Lond) ; 5(9): 1415-33, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21128723

RESUMEN

Research in designing and engineering long-circulating nanoparticles, so-called 'stealth' nanoparticles, has been attracting increasing interest as a new platform for targeted drug delivery, especially in chemotherapy. In particular, the modification of nanoparticulate surfaces with poly(ethylene glycol) derivatives has illustrated a decreased uptake of nanoparticles by mononuclear phagocyte system cells and, hence, an increased circulation time, allowing passive accumulation in the tumor. The clinical trials on patients with solid tumors are described in this article, to illustrate this generation of promising nanoparticles. In the last few years, the new-generation technique of grafting ligands on the nanoparticle surface in order to target and penetrate specific cancer cells has been developed. This article discusses the benefits of passive targeting for drug delivery to the solid tumors via the enhanced permeability and retention effect, when using stealth nanoparticles, and compares them with the advantages of active targeting.


Asunto(s)
Antineoplásicos/administración & dosificación , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/administración & dosificación , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Humanos
10.
J Enzyme Inhib Med Chem ; 22(5): 608-19, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18035829

RESUMEN

In an attempt to combine the anti-HIV inhibitory capacity of reverse transcriptase (RT) inhibitors (NRTIs) and integrase (IN) inhibitors (INIs), several heterodimer analogues of the previously reported [d4T]-PABC-[INI] and [d4T]-OABC-[INI] prototypes have been prepared. In these novel series, we wished to extend our results to conjugates which incorporated an enzymatically labile aminoacid unit (L-alanine) connected to d4T through a self-immolative para- or ortho-aminobenzyl carbonate (PABC or OABC) spacer. Among the novel heterodimers, several derivatives show a potent anti-HIV-1 activity, which proved comparable to that of the [L-708,906]-PABC-[d4T] Heterodimer A prototype. However, although the compounds proved inhibitory to HIV-1, they were less potent than the parent compounds from which they were derived.


Asunto(s)
Alanina/química , Fármacos Anti-VIH/síntesis química , Fármacos Anti-VIH/farmacología , Inhibidores de Integrasa VIH/química , VIH/efectos de los fármacos , Profármacos/síntesis química , Inhibidores de la Transcriptasa Inversa/química , Estavudina/química , Fármacos Anti-VIH/química , Células Cultivadas , Dimerización , Concentración 50 Inhibidora , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Profármacos/química
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