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1.
Front Vet Sci ; 10: 1242599, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37822952

RESUMO

A 25-day-old male common bottlenose dolphin (Tursiops truncatus) died suddenly while swimming at a dolphinarium. The gross examination revealed ulceration on the dorsal and pectoral fins and rostrum. Severe congestion, hemorrhage, and edema were observed in the gastrointestinal tract, liver, mesenteric lymph nodes, lungs, and kidneys. Fibrinosuppurative arthritis of the atlantooccipital joint and extension of fibrin into the spinal canal caused compression of the spinal cord. Histopathological examination revealed tracheitis, fibrinosuppurative bronchopneumonia and enteritis. In the central nervous system, meningeal vessel congestion in the brain, and intraparenchymal hemorrhages with neurodegeneration were observed in the spinal cord. Based on the histopathological findings, representative samples, including lung, liver, mesenteric lymph node, blood obtained from the jugular vein, and fluid sample of the ascites, were inoculated on tryptic soy agar and blood agar for routine bacterial isolation. Each isolated bacterial colony was streaked aseptically onto tryptic soy agar and blood agar for pure culture. After then, polymerase chain reaction (PCR) was performed for further identification of pathogenic microorganisms. PCR identified Escherichia fergusonii, Shewanella haliotis, Enterococcus faecalis, and Staphylococcus schleiferi. E. fergusonii was considered the primary etiologic agent in this case since it was the only species identified in all representative samples. The cause of death in this animal was E. fergusonii sepsis. To the best of our knowledge, this is the first case of neonatal sepsis associated with E. fergusonii infection in a dolphin, and suggests E. fergusonii as an opportunistic pathogen associated with sepsis in dolphins.

2.
Ecotoxicol Environ Saf ; 262: 115342, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37567104

RESUMO

Waste plastics are degraded into microplastics (MPs), which are easily accumulated in the human body through digestive tracts, via the food chain. Alcohol is a widely consumed chemical throughout the world with the ability to alter the intestinal barrier. For this reason, this study was aimed to investigate exact relevance between alcohol consumption and organ distributions of MPs in an ethanol feeding animal model characterized by disrupted intestinal mucosal barriers. In this study, C57BL/6 mice were separated into control, control + MP, ethanol (EtOH), and EtOH + MP groups. Mice in the EtOH group ingested a Lieber-DeCarli diet containing EtOH. Mice in the MP groups ingested 0.1 mg/kg fluorophore polymerized polystyrene microplastics via oral gavage polystyrene MPs via oral gavage. The EtOH + MP group showed higher MP accumulation in the liver than the control + MP group. The same pattern was observed in the intestines, spleen, and brain. This pattern was more prominent in the intestines, with the EtOH + MP group showing the most severe damage due to EtOH ingestion. This result suggests that the intestinal mucosa disruption caused by EtOH ingestion exacerbates MP accumulation in the organs. Moreover, hepatic steatosis was more severe in the EtOH + MP group than in the EtOH group, suggesting the secondary manifestation mediated by MP accumulation. This study reports a novel MP accumulation pattern in the body by providing novel insights into alcohol-induced gut permeability and microplastics toxicity from the perspective of gut-liver axis.

3.
Pharmaceutics ; 15(4)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37111779

RESUMO

Adoptive cell transfer (ACT) has shown remarkable therapeutic efficacy against blood cancers such as leukemia and lymphomas, but its effect is still limited due to the lack of well-defined antigens expressed by aberrant cells within tumors, the insufficient trafficking of administered T cells to the tumor sites, as well as immunosuppression induced by the tumor microenvironment (TME). In this study, we propose the adoptive transfer of photosensitizer (PS)-loaded cytotoxic T cells for a combinational photodynamic and cancer immunotherapy. Temoporfin (Foscan®), a clinically applicable porphyrin derivative, was loaded into OT-1 cells (PS-OT-1 cells). The PS-OT-1 cells efficiently produced a large amount of reactive oxygen species (ROS) under visible light irradiation in a culture; importantly, the combinational photodynamic therapy (PDT) and ACT with PS-OT-1 cells induced significant cytotoxicity compared to ACT alone with unloaded OT-1 cells. In murine lymphoma models, intravenously injected PS-OT-1 cells significantly inhibited tumor growth compared to unloaded OT-1 cells when the tumor tissues were locally irradiated with visible light. Collectively, this study suggests that combinational PDT and ACT mediated by PS-OT-1 cells provides a new approach for effective cancer immunotherapy.

4.
Biomaterials ; 290: 121841, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36206664

RESUMO

Immune checkpoint blockade (ICB) has shown remarkable therapeutic efficacy in a variety of cancers. However, patients exhibit unexpectedly low response rates to ICB therapy owing to the unwanted recycling and cellular abundance of PD-L1. Herein, rational design of PD-L1 multivalent binding liposome is investigated through PEGylated liposomes incorporating different ratios of PD-L1 binding peptide. Liposomes incorporating 10 mol% PD-L1 binding peptides (10-PD-L1-Lipo) promote the multivalent binding with PD-L1 on tumor cell surface, which is endocytosed for its trafficking toward the lysosomes instead of the recycling endosomes. Thereby, 10-PD-L1-Lipo leads to a significant PD-L1 degradation that prevents its recycling and cellular abundance compared to anti-PD-L1 antibody, disrupting immune escape mechanism of tumor cells and enhancing T cell-mediated antitumor immunity. Moreover, a clinically applicable doxorubicin (DOX) liposomal formulation is established via drug encapsulation into 10-PD-L1-Lipo. The resulting DOX-PD-L1-Lipo primes tumors via immunogenic chemotherapy by preferential DOX accumulation by the EPR effect and overcomes PD-L1 abundance induced following chemotherapy through multivalent binding-mediated PD-L1 degradation. As a result, the synergistic immunogenic chemotherapy and multivalent binding-mediated PD-L1 degradation by DOX-PD-L1-Lipo show significantly enhanced antitumor efficacy and immune responses in colon tumor models. Collectively, this study suggests the rationally designed PEGylated liposomes to promote PD-L1 multivalent binding providing a new route for safe and more effective ICB therapy.


Assuntos
Lipossomos , Lisossomos , Humanos , Linhagem Celular Tumoral , Polietilenoglicóis , Linfócitos T , Imunoterapia/métodos
5.
J Minim Invasive Surg ; 25(3): 106-111, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36177370

RESUMO

Purpose: Trocar-site burns occurring during laparoscopic surgery have been reported in various cases, and several efforts to reduce them are underway. This study aimed to analyze the effect of capacitive coupling on trocar site by observing electrical and histological changes for electrical skin burn injury. Methods: To measure the electrical changes relating to capacitive coupling, the temperature, current, voltage, and impedance around the trocar were measured when an open circuit and a closed circuit were formed using insulation intact instruments and repeated after insulation failure. After the experiment, the tissue around the trocar was collected, and microscopic examination was performed. Results: When open circuits were formed with the intact insulation, the impedance was significantly reduced compared to the cases of closed circuits (142.0 Ω vs. 109.3 Ω, p = 0.040). When the power was 30 W and there was insulation failure, no significant difference was measured between the open circuit and the closed circuit (147.7 Ω vs. 130.7 Ω, p = 0.103). Collagen hyalinization, nuclear fragmentation, and coagulation necrosis suggesting burns were observed in the skin biopsy at the trocar insertion site. Conclusion: This study demonstrated that even with a plastic trocar and electrosurgical instruments that have intact insulation, if an open circuit is formed, capacitive coupling increases, and trocar-site burn can occur. When using electrocautery, careful manipulation must be taken to avoid creating an open circuit to prevent capacitive coupling related to electrical skin burn.

6.
Biomaterials ; 272: 120791, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33831739

RESUMO

The effective chemotherapeutic drug, doxorubicin (DOX), elicits immunogenic cell death (ICD) and additional anticancer immune responses during chemotherapy. However, it also induces severe side effects and systemic immunosuppression, hampering its wide clinical application. Herein, we constructed cancer-activated DOX prodrug by conjugating the cathepsin B-cleavable peptide (Phe-Arg-Arg-Gly, FRRG) to a doxorubicin (DOX), resulting in FRRG-DOX that self-assembled into cancer-activated DOX prodrug nanoparticles (CAP-NPs). The resulting CAP-NPs were further stabilized with the FDA-approved compound, Pluronic F68. CAP-NPs formed stable prodrug nanoparticles and they were specifically cleaved to cytotoxic DOX molecules only in cathepsin B-overexpressing cancer cells, inducing a cancer cell-specific cytotoxicity. In particular, the CAP-NPs induced ICD through cathepsin B-cleavage mechanism only in targeted cancer cells in vitro. In colon tumor-bearing mice, selectively accumulated CAP-NPs at tumors enhanced antitumor immunity without DOX-related severe toxicity, inflammatory response and systemic immunosuppression. Moreover, cytotoxicity against immune cells infiltrated into tumor microenvironment was significantly reduced compared to free DOX, leading to increased response to checkpoint inhibitor immunotherapy. The combinatorial treatment of CAP-NPs with anti-PD-L1 exhibited high rate of complete tumor regression (50%) compared to free DOX with anti-PD-L1. Concurrently, DOX-related side effects were greatly reduced during chemoimmunotherapy. Collectively, our results suggest that cancer-activated DOX prodrug nanoparticles provide a promising approach to increase clinical benefit by inducing an immune response preferentially only to targeted cancer cells, not to normal cells and immune cells, and potentiates checkpoint inhibitor immunotherapy.


Assuntos
Nanopartículas , Neoplasias , Pró-Fármacos , Animais , Linhagem Celular Tumoral , Doxorrubicina , Imunidade , Camundongos , Neoplasias/tratamento farmacológico
7.
J Control Release ; 305: 1-17, 2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31054991

RESUMO

Receptor targeted imaging has emerged as a promising tools for imaging tumor tissues. Receptor targeted molecular imaging confers critical information on clinicians including tumor location, expression level of certain receptors, and biological process, which enables early diagnosis and treatment of tumor to control cancer mortality. Receptor targeted probe design is a key to successfully deliver accurate information through many imaging modalities. When designing receptor targeted imaging probes, a variety of targeting receptors and imaging modalities are selected depending on type of cancer because overexpression of receptors are variant among tumors and each imaging modality has advantages and disadvantages. Subsequently selecting appropriate tumor targeting strategies is critical to efficiently visualize tumor of interest. In this review, we presented the strategies commonly used for designing receptor targeted probes and summarized the recent studies that implemented each strategies.


Assuntos
Imagem Molecular/métodos , Neoplasias/diagnóstico por imagem , Receptores de Superfície Celular/análise , Animais , Humanos , Concentração de Íons de Hidrogênio , Substâncias Luminescentes/química , Imageamento por Ressonância Magnética/métodos , Imagem Óptica/métodos , Tomografia por Emissão de Pósitrons/métodos
8.
Carbohydr Polym ; 202: 488-496, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30287027

RESUMO

Alginate (Alg) hydrogels, the most popular natural biomaterials, mimic the extracellular matrix (ECM) microenvironment and offer potential biomedical applications. Despite their excellent properties such as biocompatibility, hydrophilicity and ionic crosslinking, the absence of an intrinsic cell adhesion domain lessens their cell-carrier applications in tissue engineering. Herein, we suggest a three-dimensional (3D) cell culture system by integrating Alg hydrogel and fibroblast-derived matrix (FDM). FDM including cell-adhesion motifs, signaling, and physico-mechanical cues is prepared by the decellularization process by avoiding unfavorable chemical reactions. This cues-integrated-biomaterials (CiB) 3D platform shows increased cell viability, proliferation, chondrogenic and osteogenic differentiation of human bone-marrow-derived mesenchymal stem cells (hMSCs) in situ. The results show that the Alg/FDM hydrogel (CiB) matrix provides an excellent microenvironment for cell adhesion and can control the differentiation of hMSCs into specific lineages. Thus, these results suggest the potential applications of the Alg/FDM hydrogel matrix as a viable 3D culture system for tissue regeneration.


Assuntos
Alginatos/farmacologia , Materiais Biocompatíveis/farmacologia , Hidrogéis/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Alginatos/química , Animais , Materiais Biocompatíveis/química , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Hidrogéis/química , Camundongos , Células NIH 3T3 , Tamanho da Partícula , Propriedades de Superfície , Engenharia Tecidual
9.
Proc Biol Sci ; 283(1836)2016 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-27488653

RESUMO

Mean body size in marine animals has increased more than 100-fold since the Cambrian, a discovery that brings to attention the key life-history parameters of lifespan and growth rate that ultimately determine size. Variation in these parameters is not well understood on the planet today, much less in deep time. Here, we present a new global database of maximum reported lifespan and shell growth coupled with body size data for 1 148 populations of marine bivalves and show that (i) lifespan increases, and growth rate decreases, with latitude, both across the group as a whole and within well-sampled species, (ii) growth rate, and hence metabolic rate, correlates inversely with lifespan, and (iii) opposing trends in lifespan and growth combined with high variance obviate any demonstrable pattern in body size with latitude. Our observations suggest that the proposed increase in metabolic activity and demonstrated increase in body size of organisms over the Phanerozoic should be accompanied by a concomitant shift towards faster growth and/or shorter lifespan in marine bivalves. This prediction, testable from the fossil record, may help to explain one of the more fundamental patterns in the evolutionary and ecological history of animal life on this planet.


Assuntos
Evolução Biológica , Bivalves/crescimento & desenvolvimento , Tamanho Corporal , Longevidade , Animais , Bivalves/classificação , Ecologia , Fósseis
13.
Eur Neurol ; 60(1): 27-31, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18437045

RESUMO

BACKGROUND: In previous studies on unilateral internal carotid artery (ICA) occlusive disease, contralateral strokes have been ignored or excluded, probably because of their heterogeneity in etiology. The purpose of this study was to analyze the acute ischemic lesions contralateral to ICA occlusive disease and characterize the patterns and mechanisms of these strokes. METHODS: Eight patients, who had an acute ischemic stroke contralateral to the ICA occlusion, were enrolled. All patients underwent routine clinical evaluation including history and physical examination, laboratory tests and magnetic resonance imaging (MRI). Both magnetic resonance angiography and digital subtraction cerebral angiography, along with carotid duplex sonography, transcranial Doppler sonography, electrocardiography and echocardiography were performed to confirm the stroke subtypes. RESULTS: There were three distinctive stroke lesion patterns: (1) multiple infarcts in the border zone with or without a territorial lesion (4 patients), (2) multiple infarcts in the arterial territories sparing the border zone (2 patients), and (3) a small (<15 mm in MRI) single infarct in the internal border zone (2 patients). Overall, the patterns of ischemic lesions contralateral to the ICA occlusion were multiple and had a border zone distribution. CONCLUSION: These results suggest that the pathogenic mechanisms underlying these strokes could be the synergistic effects of both the embolism and a low flow state.


Assuntos
Isquemia Encefálica/patologia , Doenças das Artérias Carótidas/patologia , Artéria Carótida Interna/patologia , Acidente Vascular Cerebral/patologia , Adulto , Idoso , Isquemia Encefálica/epidemiologia , Doenças das Artérias Carótidas/complicações , Estenose das Carótidas/patologia , Feminino , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia
15.
Mov Disord ; 21(8): 1284-5, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16637038

RESUMO

We present a patient with essential tremor who spontaneously improved after a sensorimotor stroke related to a small cortical infarct near by the left precentral region of the brain. This finding supports the presence of cortical or transcortical motor loops that are likely involved in essential tremor and suggests a possible link with the cerebellar-thalamic-cortical pathway.


Assuntos
Infarto Cerebral/fisiopatologia , Tremor Essencial/prevenção & controle , Feminino , Lobo Frontal/irrigação sanguínea , Lobo Frontal/patologia , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Remissão Espontânea
16.
J Clin Neurol ; 2(4): 252-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20396528

RESUMO

BACKGROUND: Recent studies have demonstrated the molecular basis of the immunomodulatory and anti-inflammatory activities of 1,25-dihydroxyvitamin D(3)(1,25-(OH)(2)D(3)). This hormone improves behavioral deficits and normalizes the nigral dopamine levels in animal models of Parkinson's disease (PD). METHODS: We studied whether the administration of 1,25-(OH)(2)D(3) would protect against 6-hydroxydopa (6-OHDA)- and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neuronal injury, and its potential regulatory effect on microglia activation. RESULTS: We found that 1,25-(OH)(2)D(3) pretreatment significantly decreased 6-OHDA- and MPTP-induced dopaminergic neuronal loss in the substantia nigra pars compacta by preventing the activation of microglia. This observed neuroprotective effect in MPTP-treated mice that were given 1,25-(OH)(2)D(3) may be attributable to inhibition of proinflammatory cytokine expression. CONCLUSION: These results suggest that 1,25-(OH)(2)D(3) is a potentially valuable neuroprotective agent; it may therefore be considered for the treatment of pathologic conditions of the central nervous system, such as PD, where inflammation-induced neurodegeneration occurs.

17.
Opt Lett ; 28(19): 1781-3, 2003 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-14514099

RESUMO

A fully three-dimensional finite-difference time domain numerical model is presented for calculating the out-of-plane radiation loss in photonic-crystal slab waveguides. The propagation loss of a single-line defect waveguide in triangular-lattice photonic crystals is calculated for suspended-membrane, oxidized-lower-cladding, and deeply etched structures. The results show that low-loss waveguides are achievable for sufficiently suspended membranes and oxidized-lower-cladding structures.

18.
Opt Express ; 11(25): 3431-7, 2003 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19471475

RESUMO

We investigated group velocities and group velocity dispersion characteristics of photonic crystal waveguides and coupled resonator optical waveguides(CROW's). In photonic circuits comprised of the linear defect waveguides, the insertion of the CROW section suppresses energy flow due to its highly dispersive characteristics. We analyze the change in the group velocity and the group velocity dispersion by varying the radius of the holes in the waveguide channel. Properly designed CROW sections provide a wide range of control in the group velocity and positive/negative group velocity dispersion. They can be used as delay lines or dispersion compensators in photonic integrated circuits comprised of linear defect photonic crystal waveguides.

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