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1.
Immunity ; 54(1): 53-67.e7, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33058782

RESUMO

Several classes of antibiotics have long been known to have beneficial effects that cannot be explained strictly on the basis of their capacity to control the infectious agent. Here, we report that tetracycline antibiotics, which target the mitoribosome, protected against sepsis without affecting the pathogen load. Mechanistically, we found that mitochondrial inhibition of protein synthesis perturbed the electron transport chain (ETC) decreasing tissue damage in the lung and increasing fatty acid oxidation and glucocorticoid sensitivity in the liver. Using a liver-specific partial and acute deletion of Crif1, a critical mitoribosomal component for protein synthesis, we found that mice were protected against sepsis, an observation that was phenocopied by the transient inhibition of complex I of the ETC by phenformin. Together, we demonstrate that mitoribosome-targeting antibiotics are beneficial beyond their antibacterial activity and that mitochondrial protein synthesis inhibition leading to ETC perturbation is a mechanism for the induction of disease tolerance.


Assuntos
Antibacterianos/uso terapêutico , Doxiciclina/uso terapêutico , Fígado/imunologia , Pulmão/imunologia , Mitocôndrias/metabolismo , Sepse/tratamento farmacológico , Tetraciclina/uso terapêutico , Animais , Proteínas de Ciclo Celular/genética , Modelos Animais de Doenças , Transporte de Elétrons , Células Hep G2 , Humanos , Metabolismo dos Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
2.
Biol Lett ; 18(12): 20220232, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36541092

RESUMO

Optimistic and pessimistic cognitive biases have been described in many animals and are related to the perceived valence of the environment. We, therefore, hypothesize that such cognitive bias can be adaptive depending on environmental conditions. In reward-rich environments, an optimistic bias would be favoured, whereas in harsh environments, a pessimistic one would thrive. Here, we empirically investigated the potential adaptive value of such bias using zebrafish as a model. We first phenotyped female zebrafish in an optimistic/pessimistic axis using a previously validated judgement bias assay. Optimistic and pessimistic females were then exposed to an unpredictable chronic stress protocol for 17 days, after which fish were euthanized and the sectional area of the different ovarian structures was quantified in both undisturbed and stressed groups. Our results show that zebrafish ovarian development responded to chronic stress, and that judgement bias impacted the relative area of the vitellogenic developmental stage, with pessimists showing higher vitellogenic areas as compared with optimists. These results suggest that pessimism maximizes reproductive investment, through increased vitellogenesis, indicating a relationship between cognitive bias and life-history organismal decisions.


Assuntos
Pessimismo , Peixe-Zebra , Animais , Feminino , Pessimismo/psicologia , Julgamento , Cognição , Viés
3.
Mar Drugs ; 20(10)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36286431

RESUMO

Natural products, especially those derived from seaweeds, are starting to be seen as effective against various diseases, such as cardiovascular diseases (CVDs). This study aimed to design a novel oral formulation of bovine albumin serum nanoparticles (BSA NPs) loaded with an extract of Eisenia bicyclis and to validate its beneficial health effects, particularly targeting hypercholesterolemia and CVD prevention. Small and well-defined BSA NPs loaded with Eisenia bicyclis extract were successfully prepared exhibiting high encapsulation efficiency. Antioxidant activity and cholesterol biosynthesis enzyme 3-hydroxy-3 methylutaryl coenzyme A reductase (HMGR) inhibition, as well as reduction of cholesterol permeation in intestinal lining model cells, were assessed for the extract both in free and nanoformulated forms. The nanoformulation was more efficient than the free extract, particularly in terms of HMGR inhibition and cholesterol permeation reduction. In vitro cytotoxicity and in vivo assays in Wistar rats were performed to evaluate its safety and overall effects on metabolism. The results demonstrated that the Eisenia bicyclis extract and BSA NPs were not cytotoxic against human intestinal Caco-2 and liver HepG2 cells and were also safe after oral administration in the rat model. In addition, an innovative approach was adopted to compare the metabolomic profile of the serum from the animals involved in the in vivo assay, which showed the extract and nanoformulation's impact on CVD-associated key metabolites. Altogether, these preliminary results revealed that the seaweed extract and the nanoformulation may constitute an alternative natural dosage form which is safe and simple to produce, capable of reducing cholesterol levels, and consequently helpful in preventing hypercholesterolemia, the main risk factor of CVDs.


Assuntos
Produtos Biológicos , Doenças Cardiovasculares , Hipercolesterolemia , Nanopartículas , Phaeophyceae , Alga Marinha , Bovinos , Humanos , Ratos , Animais , Soroalbumina Bovina , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Células CACO-2 , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/prevenção & controle , Ratos Wistar , Phaeophyceae/metabolismo , Oxirredutases/metabolismo , Produtos Biológicos/metabolismo , Coenzima A/metabolismo , Portadores de Fármacos
4.
Proc Natl Acad Sci U S A ; 116(12): 5681-5686, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30833408

RESUMO

Malaria, the disease caused by Plasmodium spp. infection, remains a major global cause of morbidity and mortality. Host protection from malaria relies on immune-driven resistance mechanisms that kill Plasmodium However, these mechanisms are not sufficient per se to avoid the development of severe forms of disease. This is accomplished instead via the establishment of disease tolerance to malaria, a defense strategy that does not target Plasmodium directly. Here we demonstrate that the establishment of disease tolerance to malaria relies on a tissue damage-control mechanism that operates specifically in renal proximal tubule epithelial cells (RPTEC). This protective response relies on the induction of heme oxygenase-1 (HMOX1; HO-1) and ferritin H chain (FTH) via a mechanism that involves the transcription-factor nuclear-factor E2-related factor-2 (NRF2). As it accumulates in plasma and urine during the blood stage of Plasmodium infection, labile heme is detoxified in RPTEC by HO-1 and FTH, preventing the development of acute kidney injury, a clinical hallmark of severe malaria.


Assuntos
Heme/metabolismo , Rim/metabolismo , Malária/fisiopatologia , Animais , Apoferritinas/metabolismo , Linhagem Celular , Progressão da Doença , Células Epiteliais/metabolismo , Ferritinas/metabolismo , Ferritinas/fisiologia , Heme Oxigenase-1/metabolismo , Heme Oxigenase-1/fisiologia , Humanos , Tolerância Imunológica/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/fisiologia , Oxirredutases , Plasmodium berghei/metabolismo , Plasmodium berghei/parasitologia , Regulação para Cima
5.
J Immunol ; 202(4): 1137-1144, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30651344

RESUMO

Thymus autonomy is the capacity of the thymus to maintain T lymphocyte development and export independently of bone marrow contribution. Prolonging thymus autonomy was shown to be permissive to the development of T cell acute lymphoblastic leukemia (T-ALL), similar to the human disease. In this study, performing thymus transplantation experiments in mice, we report that thymus autonomy can occur in several experimental conditions, and all are permissive to T-ALL. We show that wild type thymi maintain their function of T lymphocyte production upon transplantation into recipients with several genotypes (and corresponding phenotypic differences), i.e., Rag2 - / - γc - / -, γc - / -, Rag2 - / - IL-7rα - / -, and IL-7rα - / - We found that the cellularity of the thymus grafts is influenced exclusively by the genotype of the host, i.e., IL-7rα-/- versus γc -/- Nonetheless, the difference in cellularity detected in thymus autonomy bore no impact on onset, incidence, immunophenotype, or pathologic condition of T-ALL. In all tested conditions, T-ALL reached an incidence of 80%, demonstrating that thymus autonomy bears a high risk of leukemia. We also analyzed the microbiota composition of the recipients and their genetic background, but none of the differences found influenced the development of T-ALL. Taken together, our data support that IL-7 drives cellular turnover non-cell autonomously, which is required for prevention of T-ALL. We found no influence for T-ALL in the specific combination of the genotypic mutations tested (including the developmental block caused by Rag deficiency), in microbiota composition, or minor differences in the genetic background of the strains.


Assuntos
Leucemia-Linfoma Linfoblástico de Células T Precursoras/imunologia , Receptores de Interleucina-7/imunologia , Timo/imunologia , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Receptores de Interleucina-7/deficiência , Receptores de Interleucina-7/genética
6.
Vet Pathol ; 58(3): 483-490, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33576305

RESUMO

Canine cutaneous mast cell tumors (ccMCTs) are currently graded according to Patnaik and Kiupel grading schemes. The qualitative and semiquantitative parameters applied in these schemes may lead to inter- and intraobserver variability. This study investigates the prognostic value of volume-weighted mean nuclear volume (vv¯), a stereological estimation that provides information about nuclear size and its variability. vv¯ of 55 ccMCTs was estimated using the "point-sampled intercept" method and compared with histological grade and clinical outcome. The clinical history of dogs treated with surgical excision alone was available for 30 ccMCTs. Statistical differences in vv¯ were found between grade II (x¯ = 115 ± 29 µm3) and grade III ccMCTs (x ¯= 197 ± 63 µm3), as well as between low-grade (x ¯= 113 ± 28 µm3) and high-grade ccMCTs (x¯ = 184 ± 63 µm3). An optimal cutoff value of vv¯ ≥ 150 µm3 and vv¯ ≥ 140 µm3 was determined for grade III and high-grade ccMCTs, respectively. In terms of prognosis, vv¯  was not able to predict the clinical outcome in 42% of the cases; however, cases with vv¯ <125 µm3 had a favorable outcome. These results indicate that, despite having limited prognostic value when used as a solitary parameter, vv¯ is highly reproducible and is associated with histological grade as well as with benign behavior.


Assuntos
Doenças do Cão , Neoplasias , Neoplasias Cutâneas , Animais , Núcleo Celular , Doenças do Cão/diagnóstico , Cães , Mastócitos , Neoplasias/veterinária , Variações Dependentes do Observador , Prognóstico , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/veterinária
7.
Int J Mol Sci ; 22(8)2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33920964

RESUMO

Insulin is a peptide hormone with many physiological functions, besides its use in diabetes treatment. An important role of insulin is related to the wound healing process-however, insulin itself is too sensitive to the external environment requiring the protective of a nanocarrier. Polymer-based nanoparticles can protect, deliver, and retain the protein in the target area. This study aims to produce and characterize a topical treatment for wound healing consisting of insulin-loaded poly-DL-lactide/glycolide (PLGA) nanoparticles. Insulin-loaded nanoparticles present a mean size of approximately 500 nm and neutral surface charge. Spherical shaped nanoparticles are observed by scanning electron microscopy and confirmed by atomic force microscopy. SDS-PAGE and circular dichroism analysis demonstrated that insulin preserved its integrity and secondary structure after the encapsulation process. In vitro release studies suggested a controlled release profile. Safety of the formulation was confirmed using cell lines, and cell viability was concentration and time-dependent. Preliminary safety in vivo assays also revealed promising results.


Assuntos
Queimaduras/fisiopatologia , Composição de Medicamentos , Insulina/administração & dosagem , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Regeneração , Pele/fisiopatologia , Administração Tópica , Animais , Sobrevivência Celular , Dicroísmo Circular , Liberação Controlada de Fármacos , Feminino , Células HaCaT , Humanos , Camundongos , Nanopartículas/química , Nanopartículas/ultraestrutura , Tamanho da Partícula , Estabilidade Proteica , Eletricidade Estática , Fatores de Tempo
8.
An Acad Bras Cienc ; 92(4): e20200435, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33295580

RESUMO

Osteoporosis is a metabolic disorder characterized by a loss of bone mass and structure and increasing the risk of fragility fractures, mostly among postmenopausal women. Sheep is a recognized large animal model for osteoporosis research. An experimental group of ewes (3-4 years old) was subjected to ovariectomy (OVX) and weekly glucocorticoid (GC) application for 24 weeks and compared with a sham control group. Blood and bone marrow parameters were analyzed before and 24 weeks after OVX and GC administration. Osteopenia was confirmed through micro-computed tomography and histomorphometric analysis of L4 vertebra in the study end. A statistically significant increase was observed in mean corpuscular volume, mean cell hemoglobin and monocytes and a decrease in red blood count and eosinophils (p<0.05). Alkaline phosphatase (ALP), gamma-glutamyl transpeptidase, magnesium and α1-globulin increased, and creatinine, albumin, sodium and estradiol decreased (p<0.05). A slight decrease of bone formation markers (bone ALP and osteocalcin) and an increase of bone resorption markers (C-terminal telopeptides of collagen type 1 and tartrate-resistant acid phosphatase) were observed, but without statistical significance. This study aims to contribute to better knowledge of sheep as a model for osteoporosis research and the consequences that a performed induction protocol may impose on organic metabolism.


Assuntos
Hematologia , Osteoporose , Animais , Medula Óssea , Remodelação Óssea , Pré-Escolar , Feminino , Glucocorticoides , Humanos , Ovariectomia , Pesquisa , Ovinos , Microtomografia por Raio-X
9.
Int J Mol Sci ; 21(24)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33353068

RESUMO

Breast cancer is one of the most frequently diagnosed malignancies and common causes of cancer death in women. Recent studies suggest that environmental exposures to certain chemicals, such as 7,12-Dimethylbenzanthracene (DMBA), a chemical present in tobacco, may increase the risk of developing breast cancer later in life. The first-line treatments for breast cancer (surgery, chemotherapy or a combination of both) are generally invasive and frequently associated with severe side effects and high comorbidity. Consequently, novel approaches are strongly required to find more natural-like experimental models that better reflect the tumors' etiology, physiopathology and response to treatments, as well as to find more targeted, efficient and minimally invasive treatments. This study proposes the development and an in deep biological characterization of an experimental model using DMBA-tumor-induction in Sprague-Dawley female rats. Moreover, a photothermal therapy approach using a near-infrared laser coupled with gold nanoparticles was preliminarily assessed. The gold nanoparticles were functionalized with Epidermal Growth Factor, and their physicochemical properties and in vitro effects were characterized. DMBA proved to be a very good and selective inductor of breast cancer, with 100% incidence and inducing an average of 4.7 tumors per animal. Epigenetic analysis showed that tumors classified with worst prognosis were hypomethylated. The tumor-induced rats were then subjected to a preliminary treatment using functionalized gold nanoparticles and its activation by laser (650-900 nm). The treatment outcomes presented very promising alterations in terms of tumor histology, confirming the presence of necrosis in most of the cases. Although this study revealed encouraging results as a breast cancer therapy, it is important to define tumor eligibility and specific efficiency criteria to further assess its application in breast cancer treatment on other species.


Assuntos
5-Metilcitosina/metabolismo , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Hipertermia Induzida , Neoplasias Mamárias Experimentais/terapia , Nanopartículas Metálicas/administração & dosagem , Modelos Teóricos , Animais , Peso Corporal , Feminino , Ouro/química , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/patologia , Nanopartículas Metálicas/química , Ratos , Ratos Sprague-Dawley
10.
J Vet Dent ; 31(1): 40-3, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24902412

RESUMO

Parotid salivary duct dilation was diagnosed in a 9-year-old male dog. The dog had undergone caudal maxillectomy on the ipsilateral side 2-years prior to presentation. Treatment consisted of parotid salivary duct excision and superficial parotidectomy that lead to the resolution of clinical signs. Transient facial neuropraxia was observed immediately after surgery and resolved spontaneously after 2-weeks. Parotid salivary duct dilation should be considered as a chronic postoperative complication following caudal maxillectomy.


Assuntos
Constrição Patológica/veterinária , Doenças do Cão/cirurgia , Maxila/cirurgia , Doenças Parotídeas/veterinária , Complicações Pós-Operatórias/veterinária , Animais , Constrição Patológica/diagnóstico , Constrição Patológica/etiologia , Constrição Patológica/cirurgia , Doenças do Cão/diagnóstico , Doenças do Cão/etiologia , Cães , Masculino , Cirurgia Ortognática , Doenças Parotídeas/diagnóstico , Doenças Parotídeas/etiologia , Doenças Parotídeas/cirurgia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Tomografia Computadorizada por Raios X/veterinária
11.
Int J Pharm ; 650: 123659, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38042383

RESUMO

Among the unique characteristics associated to gold nanoparticles (AuNPs) in biomedicine, their ability to convert light energy into heat opens ventures for improved cancer therapeutic options, such as photothermal therapy (PTT). PTT relies on the local hyperthermia of tumor cells upon irradiation with light beams, and the association of AuNPs with radiation within the near infrared (NIR) range constitutes an advantageous strategy to potentially improve PTT efficacy. Herein, it was explored the effect of the gold salt on the AuNPs' physicochemical and optical properties. Mostly spherical-like negatively charged AuNPs with variable sizes and absorbance spectra were obtained. In addition, photothermal features were assessed using in vitro phantom models. The best formulation showed the ability to increase their temperature in aqueous solution up to 19 °C when irradiated with a NIR laser for 20 min. Moreover, scanning transmission electron microscopy confirmed the rearrangement of the gold atoms in a face-centered cubic structure, which further allowed to calculate the photothermal conversion efficiency upon combination of theoretical and experimental data. AuNPs also showed local retention after being locally administered in in vivo models. These last results obtained by computerized tomography allow to consider these AuNPs as promising elements for a PTT system. Moreover, AuNPs showed high potential for PTT by resulting in in vitro cancer cells' viability reductions superior to 70 % once combine with 5 min of NIR irradiation.


Assuntos
Ouro , Nanopartículas Metálicas , Ouro/química , Fototerapia , Terapia Fototérmica , Nanopartículas Metálicas/química , Linhagem Celular Tumoral
12.
Life Sci Alliance ; 7(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38307624

RESUMO

Severe presentations of malaria emerge as Plasmodium (P.) spp. parasites invade and lyse red blood cells (RBC), producing extracellular hemoglobin (HB), from which labile heme is released. Here, we tested whether scavenging of extracellular HB and/or labile heme, by haptoglobin (HP) and/or hemopexin (HPX), respectively, counter the pathogenesis of severe presentations of malaria. We found that circulating labile heme is an independent risk factor for cerebral and non-cerebral presentations of severe P. falciparum malaria in children. Labile heme was negatively correlated with circulating HP and HPX, which were, however, not risk factors for severe P. falciparum malaria. Genetic Hp and/or Hpx deletion in mice led to labile heme accumulation in plasma and kidneys, upon Plasmodium infection This was associated with higher incidence of mortality and acute kidney injury (AKI) in ageing but not adult Plasmodium-infected mice, and was corroborated by an inverse correlation between heme and HPX with serological markers of AKI in P. falciparum malaria. In conclusion, HP and HPX act in an age-dependent manner to prevent the pathogenesis of severe presentation of malaria in mice and presumably in humans.


Assuntos
Injúria Renal Aguda , Malária , Criança , Humanos , Camundongos , Animais , Heme , Hemoglobinas , Haptoglobinas
13.
Vet Clin Pathol ; 52(2): 324-333, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36975170

RESUMO

A 9-year-old neutered male cat, previously test-positive for feline immunodeficiency virus (FIV), was presented with an history of vomiting, hyporexia, and weight loss. Panleukopenia was identified on complete blood counts, and bone marrow evaluation revealed ineffective granulocytic hyperplasia and rare neutro-, erythro-, and rubriphagocytosis. Prednisolone was initiated with no response, and progression to pancytopenia occurred. On abdominal ultrasonographic examination, splenomegaly was present. PCR testing was positive for Candidatus Mycoplasma haemominutum and IgG antibodies against Toxoplasma gondii were detected (titer 1:2560). Treatment with antibiotics, feline recombinant interferon-ω, chlorambucil, mycophenolate, and raltegravir was implemented with no clinical improvement, and splenectomy was performed. Cytologic evaluation of splenic aspirates revealed exuberant neutro-, erythro-, and rubriphagocytosis. Histopathology of the spleen also showed many erythrophagocytic macrophages with no evidence of malignancy, and a diagnosis of hemophagocytic syndrome (HS) was made. The WBC count and hematocrit reached reference values 1 day and 3 months, respectively, after splenectomy. The cat was treated with cyclosporine and lomustine. Disease progression led to the development of septic hepatitis, and the cat was euthanized. To our knowledge, this is the first case of presumptive HS in cats that might have been associated with FIV, Toxoplasma gondii, and Candidatus Mycoplasma haemominutum co-infection.


Assuntos
Doenças do Gato , Coinfecção , Vírus da Imunodeficiência Felina , Linfo-Histiocitose Hemofagocítica , Infecções por Mycoplasma , Mycoplasma , Toxoplasma , Animais , Gatos , Masculino , Linfo-Histiocitose Hemofagocítica/complicações , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/veterinária , Coinfecção/diagnóstico , Coinfecção/veterinária , Infecções por Mycoplasma/complicações , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/veterinária , Doenças do Gato/diagnóstico
14.
Life Sci Alliance ; 6(4)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36720499

RESUMO

The metalloprotease ADAM17 is a sheddase of key molecules, including TNF and epidermal growth factor receptor ligands. ADAM17 exists within an assemblage, the "sheddase complex," containing a rhomboid pseudoprotease (iRhom1 or iRhom2). iRhoms control multiple aspects of ADAM17 biology. The FERM domain-containing protein iTAP/Frmd8 is an iRhom-binding protein that prevents the precocious shunting of ADAM17 and iRhom2 to lysosomes and their consequent degradation. As pathophysiological role(s) of iTAP/Frmd8 have not been addressed, we characterized the impact of iTAP/Frmd8 loss on ADAM17-associated phenotypes in mice. We show that iTAP/Frmd8 KO mice exhibit defects in inflammatory and intestinal epithelial barrier repair functions, but not the collateral defects associated with global ADAM17 loss. Furthermore, we show that iTAP/Frmd8 regulates cancer cell growth in a cell-autonomous manner and by modulating the tumor microenvironment. Our work suggests that pharmacological intervention at the level of iTAP/Frmd8 may be beneficial to target ADAM17 activity in specific compartments during chronic inflammatory diseases or cancer, while avoiding the collateral impact on the vital functions associated with the widespread inhibition of ADAM17.


Assuntos
Neoplasias , Animais , Camundongos , Proteína ADAM17/genética , Proteína ADAM17/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Inflamação , Neoplasias/genética , Microambiente Tumoral
15.
Vet World ; 16(8): 1708-1713, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37766702

RESUMO

Background and Aims: Feline chronic gingivostomatitis (FCGS) is a frequent chronic inflammatory condition in the oral cavity with an etiopathogenesis not completely identified. This study aimed to contribute to the knowledge of FCGS by identifying the presence of feline calicivirus (FCV) antigens and natural killer (NK) cells and comparing them. Materials and Methods: Forty biopsies from the oral mucosa of cats diagnosed with chronic gingivostomatitis were subjected to immunohistochemical techniques to evaluate cells with FCV antigens and NK cells positive for CD56. Results: NK cells were identified in all samples, with an average of 725.3 ± 409.1 cells. Regarding FCV, it was identified in 18 out of 30 samples (60%), with a different number of cells with virus in between the analyzed cases. In all cases, the number of cells infected with FCV was lower than the number of NK cells present in the same samples, but there was no statistical association between them. Conclusion: This preliminary study shows that NK cells are present in gingivostomatitis lesions not exclusively caused by FCV-stimulus, as only 60% of all cases were positive for this virus, but other antigens should be considered in the etiology of FCGS.

16.
Gels ; 9(3)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36975649

RESUMO

Presently, skin burns are considered one of the main public health problems and lack therapeutic options. In recent years, silver nanoparticles (AgNPs) have been widely studied, playing an increasingly important role in wound healing due to their antibacterial activity. This work is focused on the production and characterization of AgNPs loaded in a Pluronic® F127 hydrogel, as well as assessing its antimicrobial and wound-healing potential. Pluronic® F127 has been extensively explored for therapeutic applications mainly due to its appealing properties. The developed AgNPs had an average size of 48.04 ± 14.87 nm (when prepared by method C) and a negative surface charge. Macroscopically, the AgNPs solution presented a translucent yellow coloration with a characteristic absorption peak at 407 nm. Microscopically, the AgNPs presented a multiform morphology with small sizes (~50 nm). Skin permeation studies revealed that no AgNPs permeated the skin after 24 h. AgNPs further demonstrated antimicrobial activity against different bacterial species predominant in burns. A chemical burn model was developed to perform preliminary in vivo assays and the results showed that the performance of the developed AgNPs loaded in hydrogel, with smaller silver dose, was comparable with a commercial silver cream using higher doses. In conclusion, hydrogel-loaded AgNPs is potentially an important resource in the treatment of skin burns due to their proven efficacy by topical administration.

17.
Pharmaceutics ; 15(4)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37111608

RESUMO

In recent years, gold nanoparticles (AuNPs) have aroused the interest of many researchers due to their unique physicochemical and optical properties. AuNPs are being explored in a variety of biomedical fields, either in diagnostics or therapy, particularly for localized thermal ablation of cancer cells after light irradiation. Besides the promising therapeutic potential of AuNPs, their safety constitutes a highly important issue for any medicine or medical device. For this reason, in the present work, the production and characterization of physicochemical properties and morphology of AuNPs coated with two different materials (hyaluronic and oleic acids (HAOA) and bovine serum albumin (BSA)) were firstly performed. Based on the above importantly referred issue, the in vitro safety of developed AuNPs was evaluated in healthy keratinocytes, human melanoma, breast, pancreatic and glioblastoma cancer cells, as well as in a three-dimensional human skin model. Ex vivo and in vivo biosafety assays using, respectively, human red blood cells and Artemia salina were also carried out. HAOA-AuNPs were selected for in vivo acute toxicity and biodistribution studies in healthy Balb/c mice. Histopathological analysis showed no significant signs of toxicity for the tested formulations. Overall, several techniques were developed in order to characterize the AuNPs and evaluate their safety. All these results support their use for biomedical applications.

18.
Mol Metab ; 73: 101731, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37121509

RESUMO

OBJECTIVE: The metalloprotease ADAM17 (also called TACE) plays fundamental roles in homeostasis by shedding key signaling molecules from the cell surface. Although its importance for the immune system and epithelial tissues is well-documented, little is known about the role of ADAM17 in metabolic homeostasis. The purpose of this study was to determine the impact of ADAM17 expression, specifically in adipose tissues, on metabolic homeostasis. METHODS: We used histopathology, molecular, proteomic, transcriptomic, in vivo integrative physiological and ex vivo biochemical approaches to determine the impact of adipose tissue-specific deletion of ADAM17 upon adipocyte and whole organism metabolic physiology. RESULTS: ADAM17adipoq-creΔ/Δ mice exhibited a hypermetabolic phenotype characterized by elevated energy consumption and increased levels of adipocyte thermogenic gene expression. On a high fat diet, these mice were more thermogenic, while exhibiting elevated expression levels of genes associated with lipid oxidation and lipolysis. This hypermetabolic phenotype protected mutant mice from obesogenic challenge, limiting weight gain, hepatosteatosis and insulin resistance. Activation of beta-adrenoceptors by the neurotransmitter norepinephrine, a key regulator of adipocyte physiology, triggered the shedding of ADAM17 substrates, and regulated ADAM17 expression at the mRNA and protein levels, hence identifying a functional connection between thermogenic licensing and the regulation of ADAM17. Proteomic studies identified Semaphorin 4B (SEMA4B), as a novel ADAM17-shed adipokine, whose expression is regulated by physiological thermogenic cues, that acts to inhibit adipocyte differentiation and dampen thermogenic responses in adipocytes. Transcriptomic data showed that cleaved SEMA4B acts in an autocrine manner in brown adipocytes to repress the expression of genes involved in adipogenesis, thermogenesis, and lipid uptake, storage and catabolism. CONCLUSIONS: Our findings identify a novel ADAM17-dependent axis, regulated by beta-adrenoceptors and mediated by the ADAM17-cleaved form of SEMA4B, that modulates energy balance in adipocytes by inhibiting adipocyte differentiation, thermogenesis and lipid catabolism.


Assuntos
Adipocinas , Semaforinas , Animais , Camundongos , Adipócitos Marrons/metabolismo , Adipocinas/metabolismo , Diferenciação Celular , Lipídeos , Proteômica , Receptores Adrenérgicos beta/metabolismo , Semaforinas/genética , Semaforinas/metabolismo , Termogênese/fisiologia
19.
Cancers (Basel) ; 14(24)2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36551565

RESUMO

Head and neck cancer (HNC), also known as the cancer that can affect the structures between the dura mater and the pleura, is the 6th most common type of cancer. This heterogeneous group of malignancies is usually treated with a combination of surgery and radio- and chemotherapy, depending on if the disease is localized or at an advanced stage. However, most HNC patients are diagnosed at an advanced stage, resulting in the death of half of these patients. Thus, the prognosis of advanced or recurrent/metastatic HNC, especially HNC squamous cell carcinoma (HNSCC), is notably poorer than the prognosis of patients diagnosed with localized HNC. This review explores the epidemiology and etiologic factors of HNC, the histopathology of this heterogeneous cancer, and the diagnosis methods and treatment approaches currently available. Moreover, special interest is given to the novel therapies used to treat HNC subtypes with worse prognosis, exploring immunotherapies and targeted/multi-targeted drugs undergoing clinical trials, as well as light-based therapies (i.e., photodynamic and photothermal therapies).

20.
Curr Med Res Opin ; 38(8): 1379-1382, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35770865

RESUMO

Tumor-infiltrating lymphocytes (TILs) have shown prognostic value in breast cancer. This study evaluated the TILs scores in 186 Portuguese patients diagnosed with early breast cancer, with special focus on HER2 subtype. Stromal TILs were scored on the core needle biopsies, as well as in the resected specimen in HER2+ patients submitted to neoadjuvant treatment with trastuzumab and pertuzumab. TILs were higher in tumors with negative hormone receptor status and HER2 amplifications, and in triple-negative breast cancer. In HER2+ patients treated with dual anti-HER neoadjuvant therapy, the TILs score on the surgical specimen was generally lower than in the biopsy.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/patologia , Feminino , Humanos , Linfócitos do Interstício Tumoral/patologia , Terapia Neoadjuvante , Portugal , Prognóstico , Receptor ErbB-2 , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
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