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1.
Pract Neurol ; 23(6): 527-529, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37679039

RESUMEN

A 69-year-old woman developed severe right suprabulbar pain with blurred right-sided vision. There were no haloes around lights, photophobia, nausea or vomiting. Investigations in the emergency department excluded a posterior communicating/internal carotid artery aneurysm. However, she did not have an ophthalmological assessment and the initial diagnosis was of sinusitis-related headache. An urgent ear, nose and throat assessment found no abnormality, but a local ophthalmologist subsequently diagnosed and managed the patient's acute angle closure crisis. Periocular pain always deserves detailed assessment with an accurate history, visual acuity assessment and intraocular pressure measurement.


Asunto(s)
Glaucoma de Ángulo Cerrado , Aneurisma Intracraneal , Sinusitis , Femenino , Humanos , Anciano , Glaucoma de Ángulo Cerrado/diagnóstico , Sinusitis/diagnóstico , Trastornos de la Visión , Enfermedad Aguda , Dolor , Errores Diagnósticos
2.
AAPS J ; 25(1): 18, 2023 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-36697923

RESUMEN

Immunogenicity testing to detect and characterize anti-drug antibody (ADA) is required for almost all biotherapeutics. Monoclonal antibody biotherapeutics usually have long half-lives and for high-dose indications such as oncology, high level of drug will be present in the testing samples and interfere with ADA and/or neutralization antibody (NAb) measurement. To overcome this drug interference, acid-dissociation-based sample pre-treatment such as Bead-Extraction and Acid Dissociation (BEAD) has been successfully applied. The main concern for these acid-dissociation-based methods, however, is that harsh acid treatment could denature positive control Abs as well as NAb species in testing samples. In addition, high amount of biotinylated drug is needed in order to have effective competition with high level of drug in the samples, which in turn requires expensive magnetic beads. And the whole process of magnetic beads handling is tedious if doing manually and often causes trouble during assay transfer. Here, we describe a novel method which we named as Precipitation, Acid Dissociation and Biotin-drug as Assay Drug (PABAD). This novel method will need only one step of acid dissociation, with much milder and shorter acid treatment to maximally preserve NAb activity. In addition, only a fraction of biotinylated-drug is needed and there is no need to use additional streptavidin (SA)-plate or SA-magnetic beads for extraction. Compared to a BEAD-based assay, PABAD demonstrates significantly improved recovery of acid-sensitive NAb positive controls (PCs) and similar recovery of acid-resistant NAb PCs.


Asunto(s)
Anticuerpos Monoclonales , Anticuerpos Neutralizantes , Estreptavidina , Biotina
3.
Eur J Cancer ; 150: 179-189, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33932725

RESUMEN

BACKGROUND: Circulating tumour cell (CTC)-derived organoids have the potential to provide a powerful tool for personalised cancer therapy but are restrained by low CTC numbers provided by blood samples. Here, we used diagnostic leukapheresis (DLA) to enrich CTCs from patients with metastatic prostate cancer (mPCa) and explored whether organoids provide a platform for ex vivo treatment modelling. METHODS: We prospectively screened 102 patients with mPCa and performed DLA in 40 patients with ≥5 CTCs/7.5 mL blood. We enriched CTCs from DLA using white blood cell (WBC) depletion alone or combined with EpCAM selection. The enriched CTC samples were cultured in 3D to obtain organoids and used for downstream analyses. RESULTS: The DLA procedure resulted in a median yield of 5312 CTCs as compared with 22 CTCs in 7.5 mL of blood. Using WBC depletion, we recovered 46% of the CTCs, which reduced to 12% with subsequent EpCAM selection. From the isolated and enriched CTC samples, organoid expansion succeeded in 35%. Successful organoid cultures contained significantly higher CTC numbers at initiation. Moreover, we performed treatment modelling in one organoid cell line and identified substantial tumour heterogeneity in CTCs using single cell DNA sequencing. CONCLUSIONS: DLA is an efficient method to enrich CTCs, although the modest success rate of culturing CTCs precludes large scale clinical application. Our data do suggest that DLA and subsequent processing provides a rich source of viable tumour cells. Therefore, DLA offers a promising alternative to biopsy procedures to obtain sufficient number of tumour cells to study sequential samples in patients with mPCa. TRIAL REGISTRATION NUMBER: NL6019.


Asunto(s)
Separación Celular , Leucaféresis , Células Neoplásicas Circulantes/patología , Neoplasias de la Próstata/patología , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , ADN de Neoplasias/genética , Heterogeneidad Genética , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Células Neoplásicas Circulantes/efectos de los fármacos , Células Neoplásicas Circulantes/metabolismo , Organoides , Estudios Prospectivos , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/terapia , Resultado del Tratamiento , Células Tumorales Cultivadas
4.
Mater Sci Eng C Mater Biol Appl ; 77: 935-946, 2017 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28532114

RESUMEN

A nanoparticulate photodynamic approach was employed with an objective to achieve enhanced production of singlet oxygen (1O2), for the management of posterior segment eye diseases like age related macular degeneration. The hypocrellin B (HB) loaded poly lactide-co-glycolide nanoparticle formulations were incorporated with nano silver (HBS-NPs). The optimized HBS-NPs contained 2.60±0.06mg/mL of HB and showed (i) 135.6 to 828.2nm size range, and (ii) negative zeta potential with a narrow polydispersity index. The DSC thermograms suggested the amorphous nature of HB inside the HBS-NPs. With the average encapsulation efficiency of 92.9±1.79%, the drug release from the HBS-NPs followed a biphasic pattern with an initial burst of 3.50% during first 8h followed by a sustained release of 47.82% within 3days. The interaction between nano silver and HB as assessed by the increase in spectral intensity of Raman spectrum demonstrates that HB may be attached over the nano silver. Generation of reactive oxygen species (ROS) by HBS-NPs was significantly higher than that of HB/HB-NPs. The singlet oxygen generating efficiency assessed using EPR spectrometer follows the order of nano silver>HB-NPs>pure HB drug solution>HBS-NPs. The HBS-NPs had a concentration and time dependent phototoxicity on A549 (human adeno lung carcinoma) cells in the presence of light providing a superior phototoxic effect (82.2% at 50µM) at 2h irradiation. The CAM treated with HBS-NPs showed a significant anti-angiogenic effect compared to a blank formulation. In vivo biodistribution studies revealed that intravenous administration of HBS-NPs lead into significant exposure to the posterior segment of the eye. This proof of principle study demonstrates that HB based nanoparticles may be a valuable new tool for application in ocular photodynamic therapy for the treatment of AMD in future.


Asunto(s)
Nanopartículas del Metal , Células A549 , Humanos , Perileno/análogos & derivados , Fotoquimioterapia , Quinonas , Plata , Oxígeno Singlete , Distribución Tisular
5.
J Neurosci ; 36(49): 12425-12435, 2016 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-27927959

RESUMEN

Passive immunization with anti-tau monoclonal antibodies has been shown by several laboratories to reduce age-dependent tau pathology and neurodegeneration in mutant tau transgenic mice. These studies have used repeated high weekly doses of various tau antibodies administered systemically for several months and have reported reduced tau pathology of ∼40-50% in various brain regions. Here we show that direct intrahippocampal administration of the adeno-associated virus (AAV)-vectored anti-phospho-tau antibody PHF1 to P301S tau transgenic mice results in high and durable antibody expression, primarily in neurons. Hippocampal antibody levels achieved after AAV delivery were ∼50-fold more than those reported following repeated systemic administration. In contrast to systemic passive immunization, we observed markedly reduced (≥80-90%) hippocampal insoluble pathological tau species and neurofibrillary tangles following a single dose of AAV-vectored PHF1 compared with mice treated with an AAV-IgG control vector. Moreover, the hippocampal atrophy observed in untreated P301S mice was fully rescued by treatment with the AAV-vectored PHF1 antibody. Vectored passive immunotherapy with an anti-tau monoclonal antibody may represent a viable therapeutic strategy for treating or preventing such tauopathies as frontotemporal dementia, progressive supranuclear palsy, or Alzheimer's disease. SIGNIFICANCE STATEMENT: We have used an adeno-associated viral (AAV) vector to deliver the genes encoding an anti-phospho-tau monoclonal antibody, PHF1, directly to the brain of mice that develop neurodegeneration due to a tau mutation that causes frontotemporal dementia (FTD). When administered systemically, PHF1 has been shown to modestly reduce tau pathology and neurodegeneration. Since such antibodies do not readily cross the blood-brain barrier, we used an AAV vector to deliver antibody directly to the hippocampus and observed much higher antibody levels and a much greater reduction in tau pathology. Using AAV vectors to deliver antibodies like PHF1 directly to brain may constitute a novel approach to treating various neurodegenerative disorders, such as FTD and Alzheimer's disease.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Inmunización Pasiva/métodos , Tauopatías/inmunología , Tauopatías/prevención & control , Factores de Transcripción/inmunología , Proteínas tau/genética , Animales , Anticuerpos Monoclonales/administración & dosificación , Proteínas de Unión al ADN , Dependovirus/inmunología , Femenino , Hipocampo , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microinyecciones , Mutación/genética , Ovillos Neurofibrilares/patología , Proteínas del Grupo Polycomb , Distribución Tisular
6.
Photochem Photobiol ; 88(1): 188-93, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22070614

RESUMEN

Recent preclinical and clinical testing of hypocrellin-based photosensitizer SL052 for use in photodynamic therapy (PDT) of cancer has shown encouraging results. Further optimization of its formulation for delivery could considerably extend the therapeutic efficiency of this drug. A nanoformulation encapsulating SL052 into biodegradable polymer poly(lactic-co-glycolic acid) (PLGA) was developed using a single-emulsion solvent evaporation technique and characterized in terms of particle size and loading of the photosensitizing agent. This nanoformulation, SL052-PLGA-nanoparticles (NPs), was compared with recently created nanoformulation based on polyvinylpyrrolidone (SL052-PVP-NPs) and standard liposomal SL052 preparation in terms of efficacy when used for PDT treatment of squamous cell carcinomas SCCVII growing subcutaneously in syngeneic mice. The therapeutic effect of PDT using these three different SL052 formulations was tested for both 1 and 4 h intervals between drug injection and tumor light exposure. The longer time interval produced higher tumor cure rates with all SL052 preparations. With both drug-light intervals, PDT based on SL052-PLGA-NPs produced superior therapeutic benefit compared with the other two SL052 formulations.


Asunto(s)
Nanotecnología , Perileno/análogos & derivados , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Quinoxalinas/farmacología , Perileno/administración & dosificación , Perileno/farmacología , Fármacos Fotosensibilizantes/administración & dosificación , Quinoxalinas/administración & dosificación
7.
Nanomedicine (Lond) ; 5(10): 1559-69, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21143033

RESUMEN

AIMS: Most sono/photosensitizers of cancer sonodynamic/photodynamic therapy (SDT/PDT), such as hypocrellin SL052, are water-insoluble, therefore restricting their clinical applications. In this article, we present a water-soluble nanocarrier to load the SDT/PDT sensitizer SL052 with improved pharmacokinetics and therapeutic efficacy. MATERIALS & METHODS: Nanoclusters of polyvinylpyrrolidones with SL052 formed water-soluble nanoparticles (SL052-NPs) while retaining the chemical structure of SL052. RESULTS: The experimental results show that SL052-NPs improve the drug's physicochemical properties and significantly enhance the efficacy of SL052 in terms of pharmacokinetics and cancer killing. Water-soluble SL052-NPs can be used to deliver the drug to deep cancer tissues. A potential benefit of SL052-NPs is that polyvinylpyrrolidones can help SL052 evade the reticuloendothelial system, thereby increasing circulation half-life and improving drug biodistribution. CONCLUSION: SL052-NPs greatly improved the physicochemical properties of SL052 without modifying its chemical structure, allowing for deep-site cancer drug delivery, imaging for diagnosis, and ultrasound or photocontrolled localized cancer therapy.


Asunto(s)
Nanopartículas/uso terapéutico , Neoplasias/tratamiento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/uso terapéutico , Agua/química , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Nanopartículas/química , Perileno/análogos & derivados , Perileno/uso terapéutico , Fármacos Fotosensibilizantes/farmacología , Quinoxalinas/uso terapéutico , Solubilidad
8.
Photodiagnosis Photodyn Ther ; 7(2): 106-14, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20510305

RESUMEN

BACKGROUND: Current limitations of interstitial photodynamic therapy (PDT) for treatment of prostate cancer include low drug selectivity after intravenous (i.v.) administration and incomplete ablation of glandular tissue. To overcome these limitations, intra-arterial (i.a.) injection of a photosensitizer was tested in a canine model. METHODS: A lipophilic photosensitizer, SL052 formulated in liposomes or dissolved in dimethyl sulphoxide (DMSO), was injected into male dogs as an intravenous injection or intra-arterially via the prostate arteries. Optical fibers were inserted into the prostate 3h after i.v. or immediately following i.a. drug delivery. Laser light was delivered through the fibers in cycles controlled by a computer-driven switch. Drug concentration (fluorescence) and light transmission in prostate tissue were monitored during the course of PDT. Side effect profile and completeness of prostate gland ablation were the primary parameters compared among treatment groups. Control animals received drug-only or light-only treatment. RESULTS AND CONCLUSION: Thirteen dogs were treated by PDT mediated by i.a. injection of SL052 dissolved in DMSO and attained either complete ablation of prostatic glandular tissue or significant reduction of prostate volume compared with that of pre-PDT (p<0.0001). When compared to i.v. administration the i.a. route resulted in more complete photo-ablation. Associated side effect included acute urinary retention which resolved overtime. No incontinence was observed. With careful tailoring of PDT drug and light doses, interstitial PDT with i.a. injection of SL052-DMSO has the potential to provide effective treatment for prostate disease.


Asunto(s)
Liposomas , Perileno/análogos & derivados , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Quinoxalinas/química , Quinoxalinas/uso terapéutico , Animales , Perros , Infusiones Intraarteriales , Liposomas/administración & dosificación , Masculino , Estructura Molecular , Perileno/administración & dosificación , Perileno/química , Perileno/uso terapéutico , Fármacos Fotosensibilizantes/administración & dosificación , Fármacos Fotosensibilizantes/química , Quinoxalinas/administración & dosificación
9.
J Photochem Photobiol B ; 94(1): 38-44, 2009 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-18977666

RESUMEN

Two novel cyclohexane-1,2-diamino and N,N dimethyl amino-propyl substituted hypocrellin B derivatives, abbreviated as CHA2HB and DMAHB, respectively were synthesized. These derivatives exhibited enhanced absorption in phototherapeutic window. Photodynamic action of these derivatives, investigated using optical and electron spin resonance methods, depended on both Type I and Type II mechanisms. Gel electrophoresis indicated 1O2/O2(.-) mediated DNA damage. CHA2HB displayed 20 fold increase in light dependent cytotoxicity on colon cancer cell line (HCT 116) than the well-known hypocrellin B (HB). The light induced, LD(50) values for CHA2HB and DMAHB were found to be 0.1 microM and 1.5 microM, respectively. The singlet oxygen generating efficiency followed the order HB>CHA(2)HB>DMAHB. But, the enhanced red absorption as well as the hydrophilicity renders the CHA2HB a better photodynamic therapeutic agent.


Asunto(s)
Fenómenos Biofísicos , Perileno/análogos & derivados , Fotoquimioterapia , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Quinonas/química , Quinonas/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Color , División del ADN , Espectroscopía de Resonancia por Spin del Electrón , Humanos , Estructura Molecular , Oxígeno/metabolismo , Perileno/química , Perileno/farmacología , Fotoquímica , Espectrofotometría , Relación Estructura-Actividad , Superóxidos/química , Agua/química
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