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1.
Mater Horiz ; 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39355934

RESUMO

Highly emissive Ag2S nanocrystals (NCs) passivated with a gradated shell incorporating Se and Zn were synthesized in air, and the temperature dependence of their photoluminescence quantum yield (PLQY) was quantified in both organic and aqueous media at ∼1200 nm. The relevance of this parameter, measured at physiological temperatures, is highlighted for applications that rely on the near infrared (NIR) photoluminescence of NCs, such as deep NIR imaging or luminescence nanothermometry. Hyperspectral NIR imaging shows that Ag2S-based NCs with a PLQY in organic media of about 10% are inefficient for imaging at 40 °C through 20 mm thick tissue with low laser irradiation power densities. In contrast, water-transferred Ag2S-based NCs with an initial PLQY of 2% in water exhibit improved robustness against temperature changes, enabling improved imaging performance.

2.
Sci Data ; 11(1): 512, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760418

RESUMO

Given the high prevalence of lung cancer, an accurate diagnosis is crucial. In the diagnosis process, radiologists play an important role by examining numerous radiology exams to identify different types of nodules. To aid the clinicians' analytical efforts, computer-aided diagnosis can streamline the process of identifying pulmonary nodules. For this purpose, medical reports can serve as valuable sources for automatically retrieving image annotations. Our study focused on converting medical reports into nodule annotations, matching textual information with manually annotated data from the Lung Nodule Database (LNDb)-a comprehensive repository of lung scans and nodule annotations. As a result of this study, we have released a tabular data file containing information from 292 medical reports in the LNDb, along with files detailing nodule characteristics and corresponding matches to the manually annotated data. The objective is to enable further research studies in lung cancer by bridging the gap between existing reports and additional manual annotations that may be collected, thereby fostering discussions about the advantages and disadvantages between these two data types.


Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Bases de Dados Factuais , Nódulo Pulmonar Solitário/diagnóstico por imagem , Diagnóstico por Computador
3.
Rev Gastroenterol Peru ; 44(1): 67-70, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38734914

RESUMO

Acute gastric variceal bleeding is a life-threatening condition that could be effectively treated with endoscopic cyanoacrylate injection diluted with lipiodol. The mixture acts as a tissue adhesive that polymerizes when in contact with blood in a gastric varix. This work reports a patient that presented to the emergency department with upper gastrointestinal bleeding due to acute variceal bleeding, who developed systemic embolization following cyanoacrylate injection therapy. This complication culminated in cerebral, splenic and renal infarctions with a fatal outcome. Systemic embolization is a very rare, but the most severe complication associated with endoscopic cyanoacrylate injection and should be considered in patients undergoing this treatment.


Assuntos
Cianoacrilatos , Varizes Esofágicas e Gástricas , Hemorragia Gastrointestinal , Adesivos Teciduais , Humanos , Cianoacrilatos/uso terapêutico , Cianoacrilatos/administração & dosagem , Cianoacrilatos/efeitos adversos , Embolia/etiologia , Embolia/terapia , Embolização Terapêutica/métodos , Varizes Esofágicas e Gástricas/terapia , Varizes Esofágicas e Gástricas/etiologia , Evolução Fatal , Hemorragia Gastrointestinal/terapia , Hemorragia Gastrointestinal/etiologia , Adesivos Teciduais/uso terapêutico , Adesivos Teciduais/administração & dosagem
4.
Molecules ; 29(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38675647

RESUMO

This study aimed to develop multifunctional nanoplatforms for both cancer imaging and therapy using superparamagnetic iron oxide nanoparticles (SPIONs). Two distinct synthetic methods, reduction-precipitation (MR/P) and co-precipitation at controlled pH (MpH), were explored, including the assessment of the coating's influence, namely dextran and gold, on their magnetic properties. These SPIONs were further functionalized with gadolinium to act as dual T1/T2 contrast agents for magnetic resonance imaging (MRI). Parameters such as size, stability, morphology, and magnetic behavior were evaluated by a detailed characterization analysis. To assess their efficacy in imaging and therapy, relaxivity and hyperthermia experiments were performed, respectively. The results revealed that both synthetic methods lead to SPIONs with similar average size, 9 nm. Mössbauer spectroscopy indicated that samples obtained from MR/P consist of approximately 11-13% of Fe present in magnetite, while samples obtained from MpH have higher contents of 33-45%. Despite coating and functionalization, all samples exhibited superparamagnetic behavior at room temperature. Hyperthermia experiments showed increased SAR values with higher magnetic field intensity and frequency. Moreover, the relaxivity studies suggested potential dual T1/T2 contrast agent capabilities for the coated SPpH-Dx-Au-Gd sample, thus demonstrating its potential in cancer diagnosis.


Assuntos
Meios de Contraste , Nanopartículas Magnéticas de Óxido de Ferro , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita , Nanomedicina Teranóstica , Nanopartículas Magnéticas de Óxido de Ferro/química , Imageamento por Ressonância Magnética/métodos , Meios de Contraste/química , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapêutico , Humanos , Ouro/química , Dextranos/química , Gadolínio/química , Propriedades de Superfície , Hipertermia Induzida/métodos , Tamanho da Partícula
5.
Rev. gastroenterol. Perú ; 44(1): 67-70, ene.-mar. 2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1560051

RESUMO

ABSTRACT Acute gastric variceal bleeding is a life-threatening condition that could be effectively treated with endoscopic cyanoacrylate injection diluted with lipiodol. The mixture acts as a tissue adhesive that polymerizes when in contact with blood in a gastric varix. This work reports a patient that presented to the emergency department with upper gastrointestinal bleeding due to acute variceal bleeding, who developed systemic embolization following cyanoacrylate injection therapy. This complication culminated in cerebral, splenic and renal infarctions with a fatal outcome. Systemic embolization is a very rare, but the most severe complication associated with endoscopic cyanoacrylate injection and should be considered in patients undergoing this treatment.


RESUMEN La hemorragia digestiva por várices gástricas es una afección potencialmente mortal que puede tratarse eficazmente con la inyección endoscópica de cianoacrilato diluida con lipiodol. La mezcla actúa como un adhesivo tisular que se polimeriza cuando entra en contacto con la sangre de la várice gástrica. Este trabajo nos reporta un paciente que acudió al servicio de urgencias con hemorragia digestiva alta debido a hemorragia aguda por várices, que desarrolló embolización sistémica después de la terapia con inyección de cianoacrilato. Esta complicación culminó en infartos cerebrales, esplénicos y renales con desenlace fatal. La embolización sistémica es una complicación muy rara, pero con alta mortalidad, asociada con la inyección endoscópica de cianoacrilato y debe considerarse en pacientes sometidos a este tratamiento.

6.
Mycopathologia ; 188(5): 623-641, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37380874

RESUMO

Aspergillosis is a mycotic infection induced by airborne fungi that are ubiquitous. Inhalation of Aspergillus conidia results in transmission through the respiratory tract. The clinical presentation is dependent on organism and host specifics, with immunodeficiency, allergies, and preexisting pulmonary disease constituting the most important risk factors. In recent decades, the incidence of fungal infections has increased dramatically, due in part to the increased number of transplants and the pervasive use of chemotherapy and immunosuppressive drugs. The spectrum of clinical manifestations can range from an asymptomatic or mild infection to a swiftly progressive, life-threatening illness. Additionally, invasive infections can migrate to extrapulmonary sites, causing infections in distant organs. Recognition and familiarity with the various radiological findings in the appropriate clinical context are essential for patient management and the prompt initiation of life-saving treatment. We discuss the radiological characteristics of chronic and invasive pulmonary aspergillosis, as well as some of the typically unexpected extrapulmonary manifestations of disseminated disease.

7.
Biomater Adv ; 151: 213443, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37146526

RESUMO

Photothermal therapy has emerged as a new promising strategy for the management of cancer, either alone or combined with other therapeutics, such as chemotherapy. The use of nanoparticles for multimodal therapy can improve treatment performance and reduce drug doses and associated side effects. Here we propose the development of a novel multifunctional nanosystem based on solid lipid nanoparticles co-loaded with gold nanorods and mitoxantrone and functionalized with folic acid for dual photothermal therapy and chemotherapy of breast cancer. Nanoparticles were produced using an economically affordable method and presented suitable physicochemical properties for tumor passive accumulation. Upon Near-Infrared irradiation (808 nm, 1.7 W cm-2, 5 min), nanoparticles could effectively mediate a temperature increase of >20 °C. Moreover, exposure to light resulted in an enhanced release of Mitoxantrone. Furthermore, nanoparticles were non-hemolytic and well tolerated by healthy cells even at high concentrations. The active targeting strategy was found to be successful, as shown by the greater accumulation of the functionalized nanoparticles in MCF-7 cells. Finally, the combined effects of chemotherapy, light-induced drug release and photothermal therapy significantly enhanced breast cancer cell death. Overall, these results demonstrate that the developed lipid nanosystem is an efficient vehicle for breast cancer multimodal therapy.


Assuntos
Neoplasias da Mama , Nanopartículas , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Mitoxantrona/uso terapêutico , Terapia Fototérmica , Nanopartículas/uso terapêutico , Nanopartículas/química
8.
Cancers (Basel) ; 15(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36672333

RESUMO

Colorectal cancer is the third most common cancer worldwide. Despite recent advances in the treatment of this pathology, which include a personalized approach using radio- and chemotherapies in combination with advanced surgical techniques, it is imperative to enhance the performance of these treatments and decrease their detrimental side effects on patients' health. Nanomedicine is likely the pathway towards solving this challenge by enhancing both the therapeutic and diagnostic capabilities. In particular, plasmonic nanoparticles show remarkable potential due to their dual therapeutic functionalities as photothermal therapy agents and as radiosensitizers in radiotherapy. Their dual functionality, high biocompatibility, easy functionalization, and targeting capabilities make them potential agents for inducing efficient cancer cell death with minimal side effects. This review aims to identify the main challenges in the diagnosis and treatment of colorectal cancer. The heterogeneous nature of this cancer is also discussed from a single-cell point of view. The most relevant works in photo- and radiotherapy using nanotechnology-based therapies for colorectal cancer are addressed, ranging from in vitro studies (2D and 3D cell cultures) to in vivo studies and clinical trials. Although the results using nanoparticles as a photo- and radiosensitizers in photo- and radiotherapy are promising, preliminary studies showed that the possibility of combining both therapies must be explored to improve the treatment efficiency.

9.
Biochim Biophys Acta Biomembr ; 1865(3): 184115, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36603803

RESUMO

There is a growing need for alternatives to target and treat bacterial infection. Thus, the present work aims to develop and optimize the production of PEGylated magnetoliposomes (MLPs@PEG), by encapsulating superparamagnetic iron oxide nanoparticles (SPIONs) within fusogenic liposomes. A Box-Behnken design was applied to modulate size distribution variables, using lipid concentration, SPIONs amount and ultrasonication time as independent variables. As a result of the optimization, it was possible to obtain MLPs@PEG with a mean size of 182 nm, with polydispersity index (PDI) of 0.19, and SPIONs encapsulation efficiency (%EE) around 76%. Cytocompatibility assays showed that no toxicity was observed in fibroblasts, for iron concentrations up to 400µg/ml. Also, for safe lipid and iron concentrations, no hemolytic effect was detected. The fusogenicity of the nanosystems was first evaluated through lipid mixing assays, based on Förster resonance energy transfer (FRET), using liposomal membrane models, mimicking bacterial cytoplasmic membrane and eukaryotic plasma membrane. It was shown that the hybrid nanosystems preferentially interact with the bacterial membrane model. Confocal microscopy and fluorescence lifetime measurements, using giant unilamellar vesicles (GUVs), validated these results. Overall, the developed hybrid nanosystem may represent an efficient drug delivery system with improved targetability for bacterial membrane.


Assuntos
Sistemas de Liberação de Medicamentos , Lipossomas Unilamelares , Ferro , Lipídeos
10.
Medicine (Baltimore) ; 101(48): e31471, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36482560

RESUMO

BACKGROUND: Niemann-Pick disease Type C (NPC) is a genetic, incurable, neurodegenerative disorder. This orphan disease is most frequently caused by mutations in the NPC1 protein, resulting in intralysossomal cholesterol accumulation. NPC1 is found in neuronal cell bodies, axon terminals and synaptosomes, suggesting it plays a role in lysosomal degradation pathway and in synaptic transmission. Neuronal function is especially vulnerable to NPC1 deficiency and synaptic changes seem a key element in disease development. Currently, Miglustat (Zavesca®) is the only approved treatment for NPC. However, preclinical evidence showed that low-dose Efavirenz reverted synaptic defects through pharmacological activation of the enzyme CYP46. METHODS: This is a single-center, phase II clinical trial to evaluate the efficacy and safety of Efavirenz in addition to standard of care in patients diagnosed with adult or late juvenile-onset NPC with cognitive impairment. All enrolled patients will be treated orally with 25 mg/d of Efavirenz for 52 weeks (1 year). Secondary objectives include evaluating clinical (neurological and neuropsychological questionnaires) and biological (imaging and biochemical biomarkers) parameters. DISCUSSION: NPC is still an unmet medical need. Although different therapeutic approaches are under study, this is the first clinical trial (to the best of our knowledge) studying the effects of Efavirenz in adult- and late-juvenile-onset NPC. Despite the small sample size and the single-arm design, we expect the results to show Efavirenz's capacity of activating the CYP46 enzyme to compensate for NPC1 deficiency and correct synaptic changes, therefore compensating cognitive and psychiatric changes in these patients. This study may provide direct benefit to enrolled patients in terms of slowing down the disease progression.


Assuntos
Disfunção Cognitiva , Doença de Niemann-Pick Tipo C , Humanos , Adulto , Doença de Niemann-Pick Tipo C/tratamento farmacológico , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia
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