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1.
Cancer ; 130(6): 985-994, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-37962072

RESUMO

BACKGROUND: Although immunotherapy has emerged as a therapeutic strategy for many cancers, there are limited studies establishing the safety and efficacy in people living with HIV (PLWH) and cancer. METHODS: PLWH and solid tumors or Kaposi sarcoma (KS) receiving antiretroviral therapy and a suppressed HIV viral load received nivolumab at 3 mg/kg every 2 weeks, in two dose deescalation cohorts stratified by CD4 count (stratum 1: CD4 count > 200/µL and stratum 2: CD4 count 100-199/µL). An expansion cohort of 24 participants with a CD4 count > 200/µL was then enrolled. RESULTS: A total of 36 PLWH received nivolumab, including 15 with KS and 21 with a variety of other solid tumors. None of the first 12 participants had dose-limiting toxicity in both CD4 strata, and five patients (14%) overall had grade 3 or higher immune related adverse events. Objective partial response occurred in nine PLWH and cancer (25%), including in six of 15 with KS (40%; 95% CI, 16.3-64.7). The median duration of response was 9.0 months overall and 12.5 months in KS. Responses were observed regardless of PDL1 expression. There were no significant changes in CD4 count or HIV viral load. CONCLUSIONS: Nivolumab has a safety profile in PLWH similar to HIV-negative subjects with cancer, and also efficacy in KS. Plasma HIV remained suppressed and CD4 counts remained stable during treatment and antiretroviral therapy, indicating no adverse impact on immune function. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02408861.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Sarcoma de Kaposi , Humanos , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Nivolumabe/efeitos adversos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Sarcoma de Kaposi/tratamento farmacológico , Contagem de Linfócito CD4 , Carga Viral
2.
J Med Virol ; 96(5): e29684, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38773828

RESUMO

Kaposi's sarcoma (KS) may derive from Kaposi's sarcoma herpesvirus (KSHV)-infected human mesenchymal stem cells (hMSCs) that migrate to sites characterized by inflammation and angiogenesis, promoting the initiation of KS. By analyzing the RNA sequences of KSHV-infected primary hMSCs, we have identified specific cell subpopulations, mechanisms, and conditions involved in the initial stages of KSHV-induced transformation and reprogramming of hMSCs into KS progenitor cells. Under proangiogenic environmental conditions, KSHV can reprogram hMSCs to exhibit gene expression profiles more similar to KS tumors, activating cell cycle progression, cytokine signaling pathways, endothelial differentiation, and upregulating KSHV oncogenes indicating the involvement of KSHV infection in inducing the mesenchymal-to-endothelial (MEndT) transition of hMSCs. This finding underscores the significance of this condition in facilitating KSHV-induced proliferation and reprogramming of hMSCs towards MEndT and closer to KS gene expression profiles, providing further evidence of these cell subpopulations as precursors of KS cells that thrive in a proangiogenic environment.


Assuntos
Herpesvirus Humano 8 , Células-Tronco Mesenquimais , Sarcoma de Kaposi , Humanos , Herpesvirus Humano 8/fisiologia , Herpesvirus Humano 8/genética , Sarcoma de Kaposi/virologia , Células-Tronco Mesenquimais/virologia , Diferenciação Celular , Células Cultivadas , Perfilação da Expressão Gênica , Proliferação de Células
3.
Blood ; 139(7): 967-982, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-34695199

RESUMO

Adult T-cell leukemia/lymphoma (ATL) is an aggressive neoplasm immunophenotypically resembling regulatory T cells, associated with human T-cell leukemia virus type-1. Here, we performed whole-genome sequencing (WGS) of 150 ATL cases to reveal the overarching landscape of genetic alterations in ATL. We discovered frequent (33%) loss-of-function alterations preferentially targeting the CIC long isoform, which were overlooked by previous exome-centric studies of various cancer types. Long but not short isoform-specific inactivation of Cic selectively increased CD4+CD25+Foxp3+ T cells in vivo. We also found recurrent (13%) 3'-truncations of REL, which induce transcriptional upregulation and generate gain-of-function proteins. More importantly, REL truncations are also common in diffuse large B-cell lymphoma, especially in germinal center B-cell-like subtype (12%). In the non-coding genome, we identified recurrent mutations in regulatory elements, particularly splice sites, of several driver genes. In addition, we characterized the different mutational processes operative in clustered hypermutation sites within and outside immunoglobulin/T-cell receptor genes and identified the mutational enrichment at the binding sites of host and viral transcription factors, suggesting their activities in ATL. By combining the analyses for coding and noncoding mutations, structural variations, and copy number alterations, we discovered 56 recurrently altered driver genes, including 11 novel ones. Finally, ATL cases were classified into 2 molecular groups with distinct clinical and genetic characteristics based on the driver alteration profile. Our findings not only help to improve diagnostic and therapeutic strategies in ATL, but also provide insights into T-cell biology and have implications for genome-wide cancer driver discovery.


Assuntos
Ataxina-1/genética , Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Leucemia-Linfoma de Células T do Adulto/patologia , Mutação , Proteínas Proto-Oncogênicas c-rel/genética , Proteínas Repressoras/genética , Animais , Variações do Número de Cópias de DNA , Feminino , Genoma Humano , Humanos , Leucemia-Linfoma de Células T do Adulto/genética , Camundongos , Camundongos Endogâmicos C57BL , Prognóstico , Taxa de Sobrevida , Sequenciamento do Exoma
4.
Lett Appl Microbiol ; 76(3)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36841234

RESUMO

Coxiella burnetii, the causative agent of Q fever, is a small, coccoid, Gram-negative strict intracellular pathogen. One of the most common ways of acquiring Q fever is through inhalation of aerosols containing the bacteria. Because C. burnetii is highly infectious, spreads easily through the air, and is very resistant to environmental conditions, it is considered a biological threat. This paper presents the development and validation of a specific real-time polymerase chain reaction (real-time PCR or qPCR) assay for the detection of C. burnetii, based on the amplification of a fragment of the isocitrate dehydrogenase (icd) encoding gene. This real-time PCR is highly specific, reproducible, and sensitive, allowing the detection of as few as 5 genome equivalents (GEs) of C. burnetii per reaction. The method enables a rapid preliminary differentiation among strains, based on a point mutation at nucleotide 745 of the icd gene. The assay was successfully evaluated in environmental soil samples; a limit of detection of 3 × 104 colony forming units per 0.5 g of soil (∼3 GEs per reaction) was achieved. The newly developed real-time PCR offers a valuable tool for differential detection of C. burnetii strains in environmental soil samples.


Assuntos
Coxiella burnetii , Febre Q , Humanos , Coxiella burnetii/genética , Reação em Cadeia da Polimerase em Tempo Real , Febre Q/diagnóstico , Febre Q/microbiologia , Bioensaio
5.
Chem Biodivers ; 20(4): e202201076, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36815541

RESUMO

Nowadays, light-emitting diodes (LED) provide an alternative source to sunlight with specific intensity and wavelength that promotes plant growth. The features offered by LED could also stimulate the production of secondary metabolites of pharmaceutical interest. This work analyzed the cultivation of oregano (Lippia palmeri S. Watson) in a floating root hydroponic system supplemented by full-spectrum LED artificial light. Growth indicators like height, diameter, number of shoots, and leaf length and width were measured. The essential oil (EO) composition from the leaves of wild and hydroponic conditions found thymol (41.8 %) as the main product for the former and carvacrol (47 %) in hydroponics. The antiproliferative activity of EOs on human colorectal cancer HCT-15 shows that 6.4 µg/ml for hydroponic and 7.4 µg/ml for the wild plant reduce more than 50 % the cell viability. Overall, this study indicates that hydroponic conditions and full spectrum LED modifies the composition of the EO of L. palmeri on compared with the wild plant, which effectively induces cell growth inhibition in human colorectal cancer.


Assuntos
Neoplasias Colorretais , Lippia , Óleos Voláteis , Origanum , Humanos , Hidroponia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Origanum/química , Folhas de Planta , Óleos de Plantas/farmacologia
6.
Molecules ; 28(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37630260

RESUMO

Amoebiasis is the second leading cause of death worldwide associated with parasitic disease and is becoming a critical health problem in low-income countries, urging new treatment alternatives. One of the most promising strategies is enhancing the redox imbalance within these susceptible parasites related to their limited antioxidant defense system. Metal-based drugs represent a perfect option due to their extraordinary capacity to stabilize different oxidation states and adopt diverse geometries, allowing their interaction with several molecular targets. This work describes the amoebicidal activity of five 2-(Z-2,3-diferrocenylvinyl)-4X-4,5-dihydrooxazole derivatives (X = H (3a), Me (3b), iPr (3c), Ph (3d), and benzyl (3e)) on Entamoeba histolytica trophozoites and the physicochemical, experimental, and theoretical properties that can be used to describe the antiproliferative activity. The growth inhibition capacity of these organometallic compounds is strongly related to a fine balance between the compounds' redox potential and hydrophilic character. The antiproliferative activity of diferrocenyl derivatives studied herein could be described either with the redox potential, the energy of electronic transitions, logP, or the calculated HOMO-LUMO values. Compound 3d presents the highest antiproliferative activity of the series with an IC50 of 23 µM. However, the results of this work provide a pipeline to improve the amoebicidal activity of these compounds through the directed modification of their electronic environment.


Assuntos
Amebicidas , Entamoeba histolytica , Amebicidas/farmacologia , Antioxidantes , Eletrônica
7.
Haematologica ; 106(3): 730-735, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32107337

RESUMO

Four cycles of rituximab plus CHOP chemotherapy is as effective as 6 cycles in low-risk diffuse large B-cell lymphoma (DLBCL). Here we report a post-hoc analysis of a prospective clinical trial in patients with HIV-associated DLBCL and high-grade lymphoma treated with 4-6 cycles of EPOCH plus rituximab based a response-adapted treatment strategy. 106 evaluable patients with HIV-associated DLBCL or high-grade CD20-positive non-Hodgkin's lymphoma were randomized to receive rituximab (375 mg/m2) given either concurrently prior to each infusional EPOCH cycle, or sequentially (weekly for 6 weeks) following completion of EPOCH. EPOCH consisted of a 96-hour IV infusion of etoposide, doxorubicin, and vincristine plus oral prednisone followed by IV bolus cyclophosphamide every 21 days for 4 to 6 cycles. Patients received 2 additional cycles of therapy after documentation of a complete response (CR) by computerized tomography after cycles 2 and 4. 64 of 106 evaluable patients (60%, 95% CI 50%, 70%) had a CR in both treatment arms. The 2-year event-free survival (EFS) rates were similar in the 24 patients with CR who received 4 or fewer EPOCH cycles (78%, 95% confidence intervals [55%, 90%]) due to achieving a CR after 2 cycles, compared with those who received 5-6 cycles of EPOCH (85%, 95% CI 70%, 93%) because a CR was first documented after cycle 4. A response-adapted strategy may permit a shorter treatment duration without compromising therapeutic efficacy in patients with HIV-associated lymphoma treated with EPOCH plus rituximab, which merits further evaluation in additional prospective trials. Clinical Trials.gov identifier NCT00049036.


Assuntos
Infecções por HIV , Linfoma Difuso de Grandes Células B , Linfoma não Hodgkin , Protocolos de Quimioterapia Combinada Antineoplásica , Linfócitos B , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Etoposídeo/uso terapêutico , Infecções por HIV/tratamento farmacológico , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Prednisona/uso terapêutico , Estudos Prospectivos , Rituximab/uso terapêutico , Vincristina/uso terapêutico
8.
Mol Divers ; 25(4): 2289-2305, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32627094

RESUMO

Since the beginning, natural products have represented an important source of bioactive molecules for cancer treatment. Among them, cardenolides attract the attention of different research groups due to their cardiotonic and antitumor activity. The observed biological activity is closely related to their Na+/K+-ATPase inhibition potency. Currently, the discovery of new compounds against cancer is an urgent need in modern pharmaceutical research. Thus, the aim of this work is to determine the physicochemical properties and substituent effects that module the antiproliferative activity of cardenolides on the human lung cancer cell line A549. We build and curate a library with results obtained from literature; molecular descriptors were calculated in PaDEL software, and SAR/QSAR analysis was performed. The SAR results showed that cardenolides were sensitive to modifications in C and D steroidal ring and required substituent groups with the function of hydrogen bond acceptor at the C3 position. QSAR models to doubly linked-type cardenolides indicated that properties as lipoaffinity and atoms with the capacity to be hydrogen bond acceptors are involved in the increment of antiproliferative activity on A549 cell line. In contrast, the presence and position of very electro-negative atoms on the molecule decreased the antiproliferative effect on A549 cells. These results suggest that the antiproliferative capacity of cardenolides on the cell line A549 is strongly related to substituent groups on the C3 position, which must not be carbohydrate. Additionally, the steroidal rings C and D must remain without modifications.


Assuntos
Cardenolídeos
9.
PLoS Pathog ; 14(2): e1006861, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29444188

RESUMO

Adult T-cell leukaemia/lymphoma (ATL) arises from chronic non-malignant human T lymphotropic virus type-1 (HTLV-1) infection which is characterized by high plasma pro-inflammatory cytokines whereas ATL is characterized by high plasma anti-inflammatory (IL-10) concentrations. The poor prognosis of ATL is partly ascribed to disease-associated immune suppression. ATL cells have a CD4+CCR4+CD26-CD7- immunophenotype but infected cells with this immunophenotype ('ATL-like' cells) are also present in non-malignant HTLV-1 infection. We hypothesized that 'ATL-like' and ATL cells have distinct cytokine producing capacity and a switch in the cytokines produced occurs during leukemogenesis. Seventeen asymptomatic carriers (ACs), 28 patients with HTLV-1-associated myelopathy (HAM) and 28 with ATL were studied. Plasma IL-10 concentration and the absolute frequency of IL-10-producing CD4+ T cells were significantly higher in patients with ATL compared to AC. IL-10-producing ATL cells were significantly more frequent than 'ATL-like' cells. The cytokine-producing cells were only a small fraction of ATL cells. Clonality analysis revealed that even in patients with ATL the ATL cells were composed not only of a single dominant clone (putative ATL cells) but also tens of non-dominant infected clones ('ATL-like' cells). The frequency of cytokine-producing cells showed a strong inverse correlation with the relative abundance of the largest clone in ATL cells suggesting that the putative ATL cells were cytokine non-producing and that the 'ATL-like' cells were the primary cytokine producers. These findings were confirmed by RNAseq with cytokine mRNA expression in ATL cells in patients with ATL (confirmed to be composed of both putative ATL and 'ATL-like' cells by TCR analysis) significantly lower compared to 'ATL-like' cells in patients with non-malignant HTLV-1 infection (confirmed to be composed of hundreds of non-dominant clones by TCR analysis). A significant inverse correlation between the relative abundance of the largest clone and cytokine mRNA expression was also confirmed. Finally, 'ATL-like' cells produced less pro- and more anti-inflammatory cytokines than non 'ATL-like' CD4+ cells (which are predominantly HTLV uninfected). In summary, HTLV-1 infection of CD4+ T cells is associated with a change in cytokine producing capacity and dominant malignant clonal growth is associated with loss of cytokine producing capacity. Non-dominant clones with 'ATL-like' cells contribute to plasma cytokine profile in patients with non-malignant HTLV-1 infection and are also present in patient with ATL.


Assuntos
Transformação Celular Viral/fisiologia , Citocinas/metabolismo , Infecções por HTLV-I/imunologia , Infecções por HTLV-I/metabolismo , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Leucemia-Linfoma de Células T do Adulto/virologia , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Evolução Clonal/fisiologia , Estudos de Coortes , Citocinas/sangue , Citocinas/genética , Progressão da Doença , Feminino , Infecções por HTLV-I/patologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Vírus Linfotrópico T Tipo 1 Humano/patogenicidade , Humanos , Imunofenotipagem , Leucemia-Linfoma de Células T do Adulto/imunologia , Leucemia-Linfoma de Células T do Adulto/metabolismo , Masculino , Pessoa de Meia-Idade , Paraparesia Espástica Tropical/imunologia , Paraparesia Espástica Tropical/metabolismo , Paraparesia Espástica Tropical/patologia , Paraparesia Espástica Tropical/virologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Carga Viral
10.
PLoS Pathog ; 14(4): e1006968, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29698475

RESUMO

Approximately 12% of all human cancers worldwide are caused by infections with oncogenic viruses. Kaposi's sarcoma herpesvirus/human herpesvirus 8 (KSHV/HHV8) is one of the oncogenic viruses responsible for human cancers, including Kaposi's sarcoma (KS), Primary Effusion Lymphoma (PEL), and the lymphoproliferative disorder multicentric Castleman's disease (MCD). Chronic inflammation mediated by KSHV infection plays a decisive role in the development and survival of these cancers. NF-κB, a family of transcription factors regulating inflammation, cell survival, and proliferation, is persistently activated in KSHV-infected cells. The KSHV latent and lytic expressing oncogenes involved in NF-κB activation are vFLIP/K13 and vGPCR, respectively. However, the mechanisms by which NF-κB is activated by vFLIP and vGPCR are poorly understood. In this study, we have found that a host molecule, Cell Adhesion Molecule 1 (CADM1), is robustly upregulated in KSHV-infected PBMCs and KSHV-associated PEL cells. Further investigation determined that both vFLIP and vGPCR interacted with CADM1. The PDZ binding motif localized at the carboxyl terminus of CADM1 is essential for both vGPCR and vFLIP to maintain chronic NF-κB activation. Membrane lipid raft associated CADM1 interaction with vFLIP is critical for the initiation of IKK kinase complex and NF-κB activation in the PEL cells. In addition, CADM1 played essential roles in the survival of KSHV-associated PEL cells. These data indicate that CADM1 plays key roles in the activation of NF-κB pathways during latent and lytic phases of the KSHV life cycle and the survival of KSHV-infected cells.


Assuntos
Molécula 1 de Adesão Celular/metabolismo , Linfoma de Efusão Primária/metabolismo , NF-kappa B/metabolismo , Receptores de Quimiocinas/metabolismo , Sarcoma de Kaposi/metabolismo , Proteínas Virais/metabolismo , Molécula 1 de Adesão Celular/genética , Herpesvirus Humano 8/patogenicidade , Humanos , Linfoma de Efusão Primária/genética , Linfoma de Efusão Primária/virologia , NF-kappa B/genética , Receptores de Quimiocinas/genética , Sarcoma de Kaposi/genética , Sarcoma de Kaposi/virologia , Células Tumorais Cultivadas , Proteínas Virais/genética
11.
Appl Environ Microbiol ; 86(17)2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32561586

RESUMO

Benzenoid-derived metabolites act as precursors for a wide variety of products involved in essential metabolic roles in eukaryotic cells. They are synthesized in plants and some fungi through the phenylalanine ammonia lyase (PAL) and tyrosine ammonia lyase (TAL) pathways. Ascomycete yeasts and animals both lack the capacity for PAL/TAL pathways, and metabolic reactions leading to benzenoid synthesis in these organisms have remained incompletely known for decades. Here, we show genomic, transcriptomic, and metabolomic evidence that yeasts use a mandelate pathway to synthesize benzenoids, with some similarities to pathways used by bacteria. We conducted feeding experiments using a synthetic fermentation medium that contained either 13C-phenylalanine or 13C-tyrosine, and, using methylbenzoylphosphonate (MBP) to inhibit benzoylformate decarboxylase, we were able to accumulate intracellular intermediates in the yeast Hanseniaspora vineae To further confirm this pathway, we tested in separate fermentation experiments three mutants with deletions in the key genes putatively proposed to form benzenoids (Saccharomyces cerevisiaearo10Δ, dld1Δ, and dld2Δ strains). Our results elucidate the mechanism of benzenoid synthesis in yeast through phenylpyruvate linked with the mandelate pathway to produce benzyl alcohol and 4-hydroxybenzaldehyde from the aromatic amino acids phenylalanine and tyrosine, as well as sugars. These results provide an explanation for the origin of the benzoquinone ring, 4-hydroxybenzoate, and suggest that Aro10p has benzoylformate and 4-hydroxybenzoylformate decarboxylase functions in yeast.IMPORTANCE We present here evidence of the existence of the mandelate pathway in yeast for the synthesis of benzenoids. The link between phenylpyruvate- and 4-hydroxyphenlypyruvate-derived compounds with the corresponding synthesis of benzaldehydes through benzoylformate decarboxylation is demonstrated. Hanseniaspora vineae was used in these studies because of its capacity to produce benzenoid derivatives at a level 2 orders of magnitude higher than that produced by Saccharomyces Contrary to what was hypothesized, neither ß-oxidation derivatives nor 4-coumaric acid is an intermediate in the synthesis of yeast benzenoids. Our results might offer an answer to the long-standing question of the origin of 4-hydroxybenzoate for the synthesis of Q10 in humans.


Assuntos
Derivados de Benzeno/metabolismo , Hanseniaspora/metabolismo , Ácidos Mandélicos/metabolismo , Redes e Vias Metabólicas
12.
AAPS PharmSciTech ; 21(7): 237, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32808055

RESUMO

Valero-fenbendazole (VAL-FBZ) is a novel hybrid compound with in vitro anthelmintic activity, designed and synthesized to address the global problem of resistance to anthelmintic compounds. This new molecule derives from fenbendazole (FBZ), a well-known commercially available benzimidazole used in veterinary medicine despite its poor water solubility. In this work, we report for the first time a strategy to solve the solubility problems of FBZ and VAL-FBZ by means of self-dispersible nanocrystals (SDNC). Nanocrystals were prepared by media milling followed by a spray-drying step, and a comprehensive and exhaustive structural and physicochemical characterization was carried out, in order to understand the systems and their behavior. The formulation poloxamer 188 (P188):FBZ 1:1 turned out with the best process yield (53%) and re-dispersability properties, particle size average of 258 nm, and polydispersity index of 0.2 after redispersion in water. The dissolution profile showed a markedly increased dissolution rate compared with the simple mixture of the components (80% FBZ dissolved in 15 min from the SDNC vs 14% from the control formulation). FTIR spectroscopy, thermal analysis, and X-Ray Powder Diffraction (XRPD) studies showed no chemical interactions between components and an extensive confocal Raman microscopy analysis of the formulations showed very homogeneous spatial distribution of components in the SDNC samples. This manufacturing process was then successfully transferred for preparing and characterizing VAL-FBZ:P188 (1:1) SDNC with similar results, suggesting the promising interest of a novel anthelmintic with improved biopharmaceutical behavior. In conclusion, new FBZ and VAL-FBZ SDNC with improved dissolution rate were successfully prepared and characterized. Graphical abstract.


Assuntos
Fenbendazol/química , Lactamas/química , Nanopartículas/química , Dessecação , Excipientes/química , Tamanho da Partícula , Poloxâmero/química , Difração de Pó , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Água/química
13.
Fish Shellfish Immunol ; 84: 1083-1089, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30389645

RESUMO

The global aquaculture has shown an impressive growth in the last decades contributing with a major part of total food fish supply. However, it also helps in the spread of diseases that in turn, causes great economic losses. The White Spot Syndrome Virus (WSSV) is one of the major viral pathogen for the shrimp aquaculture industry. Several attempts to eliminate the virus in the shrimp have been addressed without achieving a long-term effectiveness. In this work, we determine the capacity of the commercial non-toxic PVP-coated silver nanoparticles to promote the response of the immune system of WSSV-infected shrimps with or without an excess of iron ions. Our results showed that a single dose of metallic silver in the nanomolar range (111 nmol/shrimp), which is equivalent to 12 ng/mL of silver nanoparticles, produces 20% survival of treated infected shrimps. The same concentration administered in healthy shrimps do not show histological evidence of damage. The observed survival rate could be associated with the increase of almost 2-fold of LGBP expression levels compared with non-treated infected shrimps. LGBP is a key gene of shrimp immunological response and its up-regulation is most probably induced by the recognition of silver nanoparticles coating by specific pathogen-associated molecular pattern recognition proteins (PAMPs) of shrimp. Increased LGBP expression levels was observed even with a 10-fold lower dose of silver nanoparticles (1.2 ng/shrimp, 0.011 nmol of metallic silver/shrimp). The increase in LGBP expression levels was also observed even in the presence of iron ion excess, a condition that favors virus proliferation. Those results showed that a single dose of a slight amount of silver nanoparticles were capable to enhance the response of shrimp immune system without toxic effects in healthy shrimps. This response could be enhanced by administration of other doses and might represent an important alternative for the treatment of a disease that has still no cure, white spot syndrome virus.


Assuntos
Nanopartículas Metálicas , Penaeidae/imunologia , Substâncias Protetoras/farmacologia , Prata/farmacologia , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Imunidade Inata , Longevidade , Penaeidae/virologia
14.
Anaerobe ; 55: 130-135, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30557657

RESUMO

Anaerobiospirillum succiniciproducens is a gram-negative anaerobic spiral rod which is part of the normal flora of dogs and cats and can produce bacteraemia and diarrhoea in humans. In this report we describe two cases of bacteraemia caused by A. succiniciproducens which was successfully identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). We present a comprehensive literature review of 48 cases of A. succiniciproducens bacteraemia in which we describe previous underlying conditions, clinical presentations, identification methodology and antibiotic susceptibility data.


Assuntos
Anaerobiospirillum/isolamento & purificação , Bacteriemia/diagnóstico , Bacteriemia/microbiologia , Técnicas Bacteriológicas/métodos , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anaerobiospirillum/química , Anaerobiospirillum/classificação , Diarreia/diagnóstico , Diarreia/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Mod Pathol ; 31(7): 1046-1063, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29449683

RESUMO

Adult T-cell leukemia/lymphoma, an aggressive T-cell neoplasm, is causally linked to human T-cell lymphotropic virus type 1 and based on this association has a distinct geographic distribution. In our United States-based practice, whose population is enriched for immigrants from human T-cell lymphotropic virus type 1 endemic areas, we have identified that a subset of adult T-cell leukemia/lymphoma, in the absence of human T-cell lymphotropic virus type 1 identification, are indistinguishable from other more common T-cell neoplasms. We retrospectively gathered serology results for anti-human T-cell lymphotropic virus type 1/2 antibody in patients diagnosed with T-cell neoplasms at our institution. A total of 220 human T-cell lymphotropic virus type 1/2 positive patients with T-cell neoplasms were identified; 199 (91%) were correctly classified as adult T-cell leukemia/lymphoma or provisionally as peripheral T-cell lymphoma (serology testing pending). Twenty-one cases (9%) were initially misclassified, including the following: 13 presenting with skin +/- peripheral blood involvement and misclassified as mycosis fungoides/Sezary syndrome; 7 with lymphomatous disease, absence of leukemic involvement, and diffuse CD30 expression, misclassified as ALK- negative anaplastic large-cell lymphoma; 1 thought to represent T-prolymphocytic leukemia with TCL-1 gene rearrangement and diffuse marrow involvement. We also present an example of adult T-cell leukemia/lymphoma, which mimicked lymphoepithelioid variant of peripheral T-cell lymphoma also with diffuse marrow involvement. A subset of adult T-cell leukemia/lymphoma can closely mimic a variety of other more common T-cell neoplasms. Due to its extreme clinicopathologic heterogeneity, identification of adult T-cell leukemia/lymphoma requires a high level of suspicion based on patient demographic alone, which should prompt anti-human T-cell lymphotropic virus type 1/2 serology testing in all T-cell neoplasms developing in patients of appropriate demographic. Absence of high level of suspicion, adult T-cell leukemia/lymphoma is easily misclassified.


Assuntos
Leucemia-Linfoma de Células T do Adulto/diagnóstico , Linfoma de Células T/diagnóstico , Adulto , Idoso , Diagnóstico Diferencial , Erros de Diagnóstico , Feminino , Vírus Linfotrópico T Tipo 1 Humano , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados Unidos
16.
Artigo em Inglês | MEDLINE | ID: mdl-27895014

RESUMO

Ceftazidime-avibactam (CAZ-AVI) is a recently approved ß-lactam-ß-lactamase inhibitor combination with the potential to treat serious infections caused by carbapenem-resistant organisms. Few patients with such infections were included in the CAZ-AVI clinical trials, and clinical experience is lacking. We present a case series of patients with infections caused by carbapenem-resistant Enterobacteriaceae (CRE) or Pseudomonas aeruginosa (CRPa) who were treated with CAZ-AVI salvage therapy on a compassionate-use basis. Physicians who had prescribed CAZ-AVI completed a case report form. We used descriptive statistics to summarize patient characteristics and treatment outcomes. We used the Wilcoxon rank sum test and Fisher's exact test to compare patients by treatment outcome. The sample included 36 patients infected with CRE and two with CRPa. The most common infections were intra-abdominal. Physicians categorized 60.5% of patients as having life-threatening infections. All but two patients received other antibiotics before CAZ-AVI, for a median of 13 days. The median duration of CAZ-AVI treatment was 16 days. Twenty-five patients (65.8%) concurrently received other antibiotics to which their pathogen was nonresistant in vitro Twenty-eight patients (73.7%, 95% confidence interval [CI], 56.9 to 86.6%) experienced clinical and/or microbiological cure. Five patients (20.8%) with documented microbiological cure died, whereas 10 patients (71.4%) with no documented microbiological cure died (P = 0.01). In three-quarters of cases, CAZ-AVI (alone or combined with other antibiotics) cured infections caused by carbapenem-resistant organisms, 95% of which had failed previous therapy. Microbiological cure was associated with improved survival. CAZ-AVI shows promising clinical results for infections for which treatment options are limited.


Assuntos
Antibacterianos/uso terapêutico , Compostos Azabicíclicos/uso terapêutico , Carbapenêmicos/uso terapêutico , Ceftazidima/uso terapêutico , Idoso , Antibacterianos/farmacologia , Compostos Azabicíclicos/farmacologia , Carbapenêmicos/farmacologia , Ceftazidima/farmacologia , Combinação de Medicamentos , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/patogenicidade , Feminino , Humanos , Klebsiella oxytoca/efeitos dos fármacos , Klebsiella oxytoca/patogenicidade , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/patogenicidade , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , Terapia de Salvação
17.
PLoS Pathog ; 11(3): e1004721, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25774694

RESUMO

Persistent activation of NF-κB by the Human T-cell leukemia virus type 1 (HTLV-1) oncoprotein, Tax, is vital for the development and pathogenesis of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). K63-linked polyubiquitinated Tax activates the IKK complex in the plasma membrane-associated lipid raft microdomain. Tax also interacts with TAX1BP1 to inactivate the NF-κB negative regulatory ubiquitin-editing A20 enzyme complex. However, the molecular mechanisms of Tax-mediated IKK activation and A20 protein complex inactivation are poorly understood. Here, we demonstrated that membrane associated CADM1 (Cell adhesion molecule1) recruits Ubc13 to Tax, causing K63-linked polyubiquitination of Tax, and IKK complex activation in the membrane lipid raft. The c-terminal cytoplasmic tail containing PDZ binding motif of CADM1 is critical for Tax to maintain persistent NF-κB activation. Finally, Tax failed to inactivate the NF-κB negative regulator ubiquitin-editing enzyme A20 complex, and activate the IKK complex in the lipid raft in absence of CADM1. Our results thus indicate that CADM1 functions as a critical scaffold molecule for Tax and Ubc13 to form a cellular complex with NEMO, TAX1BP1 and NRP, to activate the IKK complex in the plasma membrane-associated lipid rafts, to inactivate NF-κB negative regulators, and maintain persistent NF-κB activation in HTLV-1 infected cells.


Assuntos
Moléculas de Adesão Celular/metabolismo , Infecções por Deltaretrovirus/metabolismo , Genes pX/fisiologia , Imunoglobulinas/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/fisiologia , Animais , Molécula 1 de Adesão Celular , Cisteína Endopeptidases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Vírus Linfotrópico T Tipo 1 Humano , Humanos , Immunoblotting , Imunoprecipitação , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células Jurkat , Camundongos , Camundongos Knockout , Microscopia Confocal , Proteínas Nucleares/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Proteína 3 Induzida por Fator de Necrose Tumoral alfa , Enzimas de Conjugação de Ubiquitina/metabolismo
18.
Biometals ; 30(1): 43-58, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27988860

RESUMO

The family of Copper(II) coordination compounds Casiopeínas® (Cas) has shown antiproliferative activity in several tumour lines by oxidative cellular damage and mitochondrial dysfunction that lead to cell death through apoptotic pathways. The goal of this work is looking for the functional mechanism of CasIIgly, CasIIIia and CasIIIEa in neuroblastoma metastatic cell line SK-N-SH, a paediatric extra-cranial tumour which is refractory to several anti-carcinogenic agents. All Cas have shown higher antiproliferative activity than cisplatin (IC50 = 123 µM) with IC50 values of 18, 22 and 63 µM for CasIIgly, CasIIIEa and CasIIIia, respectively. At low concentrations and early times (4 h), these compounds cause a disruption of the mitochondrial transmembrane potential (Δψm). Concomitantly, an important depletion of intracellular glutathione and an increase of reactive oxygen species (ROS) hydrogen peroxide and radical superoxide were observed. On the other side, the lower cytotoxic effect of Casiopeínas on cultures of human peripheral blood lymphocytes (IC50CasIIgly  = 1720 µM, IC50 CasIIIEa  = 3860 µM and IC50 CasIIIia  = 4700 µM) show the selectivity of these compounds over the tumour cells compared with the non-transformed cells. Chemically, glutathione (GSH) interacts with Casiopeínas® through the coordination of sulphur atom to the metal centre, process which facilitates the electron transfer to get Cu(I), GSSG and the posterior production of ROS. Additionally, the molecular structure of CasIIIia as nitrate is reported. These results have shown that the anticarcinogenic activity of Casiopeínas® on neuroblastoma SK-N-SH is through mitochondrial apoptosis due to the enhanced pro-oxidant environment promoted by the presence of the coordination copper compounds.


Assuntos
Apoptose/efeitos dos fármacos , Cisplatino/administração & dosagem , Mitocôndrias/efeitos dos fármacos , Neuroblastoma/tratamento farmacológico , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Linhagem Celular Tumoral , Cisplatino/química , Cobre/química , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/patologia , Neuroblastoma/patologia , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/química , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
19.
Nucleic Acids Res ; 43(11): 5364-76, 2015 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-25958394

RESUMO

The family of anticancer complexes that include the transition metal copper known as Casiopeínas® shows promising results. Two of these complexes are currently in clinical trials. The interaction of these compounds with DNA has been observed experimentally and several hypotheses regarding the mechanism of action have been developed, and these include the generation of reactive oxygen species, phosphate hydrolysis and/or base-pair intercalation. To advance in the understanding on how these ligands interact with DNA, we present a molecular dynamics study of 21 Casiopeínas with a DNA dodecamer using 10 µs of simulation time for each compound. All the complexes were manually inserted into the minor groove as the starting point of the simulations. The binding energy of each complex and the observed representative type of interaction between the ligand and the DNA is reported. With this extended sampling time, we found that four of the compounds spontaneously flipped open a base pair and moved inside the resulting cavity and four compounds formed stacking interactions with the terminal base pairs. The complexes that formed the intercalation pocket led to more stable interactions.


Assuntos
Complexos de Coordenação/química , Cobre/química , DNA/química , Substâncias Intercalantes/química , Antineoplásicos/química , Simulação de Dinâmica Molecular
20.
J Virol ; 89(23): 11786-800, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26378177

RESUMO

UNLABELLED: Adult T cell leukemia/lymphoma (ATL) is an aggressive cancer of CD4/CD25(+) T lymphocytes, the etiological agent of which is human T-cell lymphotropic virus type 1 (HTLV-1). ATL is highly refractory to current therapies, making the development of new treatments a high priority. Oncolytic viruses such as vesicular stomatitis virus (VSV) are being considered as anticancer agents since they readily infect transformed cells compared to normal cells, the former appearing to exhibit defective innate immune responses. Here, we have evaluated the efficacy and safety of a recombinant VSV that has been retargeted to specifically infect and replicate in transformed CD4(+) cells. This was achieved by replacing the single VSV glycoprotein (G) with human immunodeficiency virus type 1 (HIV-1) gp160 to create a hybrid fusion protein, gp160G. The resultant virus, VSV-gp160G, was found to only target cells expressing CD4 and retained robust oncolytic activity against HTLV-1 actuated ATL cells. VSV-gp160G was further noted to be highly attenuated and did not replicate efficiently in or induce significant cell death of primary CD4(+) T cells. Accordingly, VSV-gp160G did not elicit any evidence of neurotoxicity even in severely immunocompromised animals such as NOD/Shi-scid, IL-2Rγ-c-null (NSG) mice. Importantly, VSV-gp160G effectively exerted potent oncolytic activity in patient-derived ATL transplanted into NSG mice and facilitated a significant survival benefit. Our data indicate that VSV-gp160G exerts potent oncolytic efficacy against CD4(+) malignant cells and either alone or in conjunction with established therapies may provide an effective treatment in patients displaying ATL. IMPORTANCE: Adult T cell leukemia (ATL) is a serious form of cancer with a high mortality rate. HTLV-1 infection is the etiological agent of ATL and, unfortunately, most patients succumb to the disease within a few years. Current treatment options have failed to significantly improve survival rate. In this study, we developed a recombinant strain of vesicular stomatitis virus (VSV) that specifically targets transformed CD4(+) T cells through replacement of the G protein of VSV with a hybrid fusion protein, combining domains from gp160 of HIV-1 and VSV-G. This modification eliminated the normally broad tropism of VSV and restricted infection to primarily the transformed CD4(+) cell population. This effect greatly reduced neurotoxic risk associated with VSV infection while still allowing VSV to effectively target ATL cells.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Leucemia-Linfoma de Células T do Adulto/reabilitação , Leucemia-Linfoma de Células T do Adulto/virologia , Terapia Viral Oncolítica/métodos , Proteínas Recombinantes de Fusão/genética , Vesiculovirus/genética , Animais , Western Blotting , Primers do DNA/genética , Citometria de Fluxo , Proteína gp160 do Envelope de HIV/genética , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos NOD , Testes de Neutralização , Vírus Oncolíticos/genética , Vírus Oncolíticos/metabolismo , Vesiculovirus/metabolismo
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