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1.
Arch Gynecol Obstet ; 309(5): 2057-2062, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38492083

RESUMO

PURPOSE: The objective of this study is to assess the correlation between bleeding irregularities and the accurate placement of the intrauterine device (IUD) device in the uterine cavity, determined through transvaginal ultrasonography and hysteroscopy. In addition, the study aims to examine the cytokine profile in the uterine cavity and serum of patients experiencing bleeding irregularities after the insertion of nonhormonal IUDs. METHODS: A prospective cohort study was conducted at a single tertiary medical center, wherein patients experiencing intermenstrual bleeding and spotting after the insertion of nonhormonal IUDs were enrolled. The study involved hysteroscopic and sonographic assessments of the uterine cavity and IUD placement, along with the analysis of blood and uterine cavity cytokine profiles. RESULTS: During the period between July 2019 and February 2020, a total of eight patients who experienced intermenstrual bleeding and spotting after the insertion of nonhormonal IUDs were enrolled the study. One case was excluded since a progestative device was detected by ultrasound. Out of the five cases that underwent a thorough ultrasonographic assessment, three cases (60%) showed an embedded IUD. However, these findings were excluded by the hysteroscopic evaluation. CONCLUSION: The results suggest that ultrasonographic assessment may lead to an overdiagnosis of IUD mispositioning compared to hysteroscopy. In addition, both ultrasound and hysteroscopy have limitations in diagnosing the cause of bleeding in most cases. The role of local reactive inflammatory cytokines should be further studied.


Assuntos
Dispositivos Intrauterinos , Menorragia , Metrorragia , Gravidez , Humanos , Feminino , Histeroscopia , Menorragia/diagnóstico por imagem , Menorragia/etiologia , Estudos Prospectivos , Hemorragia , Ultrassonografia , Citocinas
2.
J Autoimmun ; 100: 52-61, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30853312

RESUMO

AS101 is an organotellurium compound with multifaceted immunoregulatory properties that is remarkable for its lack of toxicity. We tested the therapeutic effect of AS101 in experimental autoimmune uveitis (EAU), a model for human autoimmune uveitis. Unexpectedly, treatment with AS101 elicited Treg generation in vivo in otherwise unmanipulated mice. Mice immunized for EAU with the retinal antigen IRBP and treated with AS101 developed attenuated disease, as did AS101-treated recipients of retina-specific T cells activated in vitro. In both settings, eye-infiltrating effector T cells were decreased, whereas regulatory T (Treg) cells in the spleen were increased. Mechanistic studies in vitro revealed that AS101 restricted polarization of retina-specific T cells towards Th1 or Th17 lineage by repressing activation of their respective lineage-specific transcription factors and downstream signals. Retina-specific T cells polarized in vitro towards Th1 or Th17 in the presence of AS101 had impaired ability to induce EAU in naïve recipients. Finally, AS101 promoted differentiation of retina-specific T cells to Tregs in vitro independently of TGF-ß. We conclude that AS101 modulates autoimmune T cells by inhibiting acquisition and expression of effector function and by promoting Treg generation, and suggest that AS101 could be useful as a therapeutic approach for autoimmune uveitis.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Etilenos/farmacologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th17/imunologia , Uveíte/tratamento farmacológico , Animais , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Linfócitos T Reguladores/patologia , Células Th1/patologia , Células Th17/patologia , Uveíte/genética , Uveíte/imunologia , Uveíte/patologia
3.
Blood ; 125(8): 1292-301, 2015 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-25533034

RESUMO

Children with Down syndrome (DS) are at increased risk for acute myeloid leukemias (ML-DS) characterized by mixed megakaryocytic and erythroid phenotype and by acquired mutations in the GATA1 gene resulting in a short GATA1s isoform. The chromosome 21 microRNA (miR)-125b cluster has been previously shown to cooperate with GATA1s in transformation of fetal hematopoietic progenitors. In this study, we report that the expression of miR-486-5p is increased in ML-DS compared with non-DS acute megakaryocytic leukemias (AMKLs). miR-486-5p is regulated by GATA1 and GATA1s that bind to the promoter of its host gene ANK1. miR-486-5p is highly expressed in mouse erythroid precursors and knockdown (KD) in ML-DS cells reduced their erythroid phenotype. Ectopic expression and KD of miR-486-5p in primary fetal liver hematopoietic progenitors demonstrated that miR-486-5p cooperates with Gata1s to enhance their self renewal. Consistent with its activation of AKT, overexpression and KD experiments showed its importance for growth and survival of human leukemic cells. Thus, miR-486-5p cooperates with GATA1s in supporting the growth and survival, and the aberrant erythroid phenotype of the megakaryocytic leukemias of DS.


Assuntos
Síndrome de Down/genética , Eritropoese/genética , Leucemia Mieloide Aguda/genética , MicroRNAs/fisiologia , Animais , Diferenciação Celular/genética , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Pré-Escolar , Síndrome de Down/complicações , Síndrome de Down/fisiopatologia , Células Eritroides/metabolismo , Células HEK293 , Humanos , Células K562 , Leucemia Mieloide Aguda/patologia , Megacariócitos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , MicroRNAs/genética , Células Tumorais Cultivadas
4.
Behav Pharmacol ; 28(6): 458-465, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28590303

RESUMO

Ammonium trichloro (dioxoethylene-O,O') tellurate (AS101) is a synthetic organotellurium compound with potent immunomodulatory and neuroprotective properties shown to inhibit the function of integrin αvß3, a presynaptic cell-surface-adhesion receptor. As partial deletion of αvß3 downregulated reuptake of serotonin by the serotonin transporter, we hypothesized that AS101 may influence pathways regulating anxiety. AS101 was tested in the modulation of anxiety-like behavior using the selectively bred Submissive (Sub) mouse strain that develop anxiety-like behavior in response to an i.p. injection. Mice were treated daily with AS101 (i.p., 125 or 200 µg/kg) or vehicle for 3 weeks, after which their anxiety-like behavior was measured in the elevated plus maze. Animals were then culled for the measurement of serum corticosterone levels by ELISA and hippocampal expression of brain-derived neurotrophic factor (BDNF) by RT-PCR. Chronic administration of AS101 significantly reduced anxiety-like behavior of Sub mice in the elevated plus maze, according to both time spent and entries to open arms, relative to vehicle-treated controls. AS101 also markedly reduced serum corticosterone levels of the treated mice and increased their hippocampal BDNF expression. Anxiolytic-like effects of AS101 may be attributed to the modulation of the regulatory influence integrin of αvß3 upon the serotonin transporter, suggesting a multifaceted mechanism by which AS101 buffers the hypothalamic-pituitary-adrenal axis response to injection stress, enabling recovery of hippocampal BDNF expression and anxiety-like behavior in Sub mice. Further studies should advance the potential of AS101 in the context of anxiety-related disorders.


Assuntos
Ansiedade/tratamento farmacológico , Etilenos/farmacologia , Compostos de Amônio , Animais , Ansiedade/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Corticosterona/análise , Corticosterona/sangue , Modelos Animais de Doenças , Etilenos/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Imunomodulação , Integrina alfaVbeta3/metabolismo , Camundongos , Fármacos Neuroprotetores , Sistema Hipófise-Suprarrenal/metabolismo , Telúrio
5.
Chembiochem ; 17(10): 918-27, 2016 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-26991356

RESUMO

Organic Te(IV) compounds (organotelluranes) differing in their labile ligands exhibited anti-integrin activities in vitro and anti-metastatic properties in vivo. They underwent ligand substitution with l-cysteine, as a thiol model compound. Unlike inorganic Te(IV) compounds, the organotelluranes did not form a stable complex with cysteine, but rather immediately oxidized it. The organotelluranes inhibited integrin functions, such as adhesion, migration, and metalloproteinase secretion mediation in B16F10 murine melanoma cells. In comparison, a reduced derivative with no labile ligand inhibited adhesion of B16F10 cells to a significantly lower extent, thus pointing to the importance of the labile ligands of the Te(IV) atom. One of the organotelluranes inhibited circulating cancer cells in vivo, possibly by integrin inhibition. Our results extend the current knowledge on the reactivity and mechanism of organotelluranes with different labile ligands and highlight their clinical potential.


Assuntos
Integrinas/metabolismo , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Telúrio/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Modelos Animais de Doenças , Integrina alfa4beta1/antagonistas & inibidores , Integrina alfa4beta1/metabolismo , Integrinas/antagonistas & inibidores , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Compostos Organometálicos/uso terapêutico , Ligação Proteica/efeitos dos fármacos , Transplante Homólogo
6.
Mol Vis ; 22: 548-62, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27293373

RESUMO

PURPOSE: Pathological angiogenesis and chronic inflammation greatly contribute to the development of choroidal neovascularization (CNV) in chorioretinal diseases involving abnormal contact between retinal pigment epithelial (RPE) and endothelial cells (ECs), associated with Bruch's membrane rupture. We explored the ability of the small organotellurium compound octa-O-bis-(R,R)-tartarate ditellurane (SAS) to mitigate inflammatory processes in human RPE cells. METHODS: Cell adhesion assays and analyses of gene and protein expression were used to examine the effect of SAS on ARPE-19 cells or primary human RPE cells that were grown alone or in an RPE-EC co-culture. RESULTS: Adhesion assays showed that SAS inhibited αv integrins expressed on RPE cells. Co-cultures of RPE cells with ECs significantly reduced the gene expression of PEDF, as compared to RPE cells cultured alone. Both SAS and the anti-αvß3 antibody LM609 significantly enhanced the production of PEDF at both mRNA and protein levels in RPE cells. RPE cells co-cultured with EC exhibited increased gene expression of CXCL5, COX1, MMP2, IGF1, and IL8, all of which are involved in both angiogenesis and inflammation. The enhanced expression of these genes was greatly suppressed by SAS, but interestingly, remained unaffected by LM609. Zymography assay showed that SAS reduced the level of MMP-2 activity in RPE cells. We also found that SAS significantly suppressed IL-1ß-induced IL-6 expression and secretion from RPE cells by reducing the protein levels of phospho-IkappaBalpha (pIκBα). CONCLUSIONS: Our results suggest that SAS is a promising anti-inflammatory agent in RPE cells, and may be an effective therapeutic approach for controlling chorioretinal diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Inflamação/prevenção & controle , Compostos Organometálicos/farmacologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Tartaratos/farmacologia , Linhagem Celular , Quimiocina CXCL5/metabolismo , Técnicas de Cocultura , Ciclo-Oxigenase 1/metabolismo , Eletroforese em Gel de Poliacrilamida , Células Endoteliais/citologia , Ensaio de Imunoadsorção Enzimática , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Humanos , Inflamação/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Integrina alfaV/metabolismo , Interleucina-8/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Epitélio Pigmentado da Retina/metabolismo , Serpinas/genética , Serpinas/metabolismo , Telúrio/farmacologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
Inorg Chem ; 55(21): 10847-10850, 2016 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-27726342

RESUMO

Since its first crystallization, the aqueous structure of the tellurium-containing experimental drug AS-101 has never been studied. We show that, under the aqueous conditions in which it is administered, AS-101 is subjected to an immediate ligand-substitution reaction with water, yielding a stable hydrolyzed oxide anion product that is identified, for the first time, to be TeOCl3-. Studying the structure of AS-101 in propylene glycol (PG), an alcoholic solvent often used for the topical and oral administration of AS-101, revealed the same phenomenon of ligand-substitution reaction between the alcoholic ligands. Upon exposure to water, the PG-substituted product is also hydrolyzed to the same tellurium(IV) oxide form, TeOCl3-.


Assuntos
Adjuvantes Imunológicos/química , Álcoois/química , Etilenos/química , Água/química , Adjuvantes Imunológicos/administração & dosagem , Etilenos/administração & dosagem , Humanos , Hidrólise , Ligantes , Óxidos/química , Propilenoglicol/química , Solubilidade , Soluções , Solventes/química
8.
J Biol Chem ; 289(24): 17215-27, 2014 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-24764299

RESUMO

Inflammatory bowel diseases (IBDs) are a group of idiopathic, chronic immune-mediated diseases characterized by an aberrant immune response, including imbalances of inflammatory cytokine production and activated innate and adaptive immunity. Selective blockade of leukocyte migration into the gut is a promising strategy for the treatment of IBD. This study explored the effect of the immunomodulating tellurium compound ammonium trichloro (dioxoethylene-o,o') tellurate (AS101) on dextran sodium sulfate (DSS)-induced murine colitis. Both oral and intraperitoneal administration of AS101 significantly reduced clinical manifestations of IBD. Colonic inflammatory cytokine levels (IL-17 and IL-1ß) were significantly down-regulated by AS101 treatment, whereas IFN-γ was not affected. Neutrophil and α4ß7(+) macrophage migration into the tissue was inhibited by AS101 treatment. Adhesion of mesenteric lymph node cells to mucosal addressin cell adhesion molecule (MAdCAM-1), the ligand for α4ß7 integrin, was blocked by AS101 treatment both in vitro and in vivo. DSS-induced destruction of colonic epithelial barrier/integrity was prevented by AS101, via up-regulation of colonic glial-derived neurotrophic factor, which was found previously to regulate the intestinal epithelial barrier through activation of the PI3K/AKT pathway. Indeed, the up-regulation of glial-derived neurotrophic factor by AS101 was associated with increased levels of colonic pAKT and BCL-2 and decreased levels of BAX. Furthermore, AS101 treatment reduced colonic permeability to Evans blue and decreased colonic TUNEL(+) cells. Our data revealed multifunctional activities of AS101 in the DSS-induced colitis model via anti-inflammatory and anti-apoptotic properties. We suggest that treatment with the small, nontoxic molecule AS101 may be an effective early therapeutic approach for controlling human IBD.


Assuntos
Colite/tratamento farmacológico , Etilenos/uso terapêutico , Fatores Imunológicos/uso terapêutico , Administração Oral , Animais , Apoptose , Moléculas de Adesão Celular/metabolismo , Colite/induzido quimicamente , Colite/metabolismo , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Sulfato de Dextrana/toxicidade , Etilenos/administração & dosagem , Etilenos/farmacologia , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/farmacologia , Injeções Intraperitoneais , Interferon gama/genética , Interferon gama/metabolismo , Interleucina-17/genética , Interleucina-17/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mucoproteínas , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
9.
Arch Microbiol ; 196(1): 51-61, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24322541

RESUMO

The antibacterial effects of a new organo-tellurium compound [Octa-O-bis-(R,R)-tartarate ditellurane (OTD)] on Escherichia coli isolates as a model are shown. OTD was found to be a bactericidal drug. It exhibits inhibition zones on a protein-rich agar medium but not in a protein-poor medium unless a thiol is added. When applied at the lag phase, OTD inhibits more efficiently than at the log phase. Thiols enhance the efficiency at the log phase. OTD inhibits biofilm formation of E. coli. X-ray microanalysis demonstrated damage caused to the Na⁺/K⁺ pumps and leakage of potassium and phosphorous. Scanning electron microscopy demonstrated an incomplete surface of the bacterial cell wall with a concavity in the center that looks like a hole. Transmission electron microscopy demonstrated severe damage, such as depletion, perforation, and holes in the inner membrane. These results indicate for the first time that the new tellurium compound has antibacterial activities.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Tartaratos/farmacologia , Biofilmes/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
10.
Semin Cancer Biol ; 22(1): 60-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22202556

RESUMO

Tellurium is a rare element, which has been regarded as a toxic, non-essential trace element; its biological role, if any, has not been clearly established to date. The investigation of therapeutic activities of tellurium compounds is rather limited in the literature, despite the relative abundance of tellurium in the human body. Nevertheless, the varied activities of tellurium agents in both malignant and normal cells are extremely exciting, though very complex. Not surprisingly, an increased interest in tellurium among biological chemists and pharmacists has fuelled the search for more and more diverse tellurium compounds. The present review will focus on two small inorganic tellurium complexes, ammonium trichloro(dioxoethylene-O,O')tellurate (AS101) and Octa-O-bis-(R,R)-tartarate ditellurane (SAS), thoroughly investigated by us, converging at their anti-cancer properties, and elucidating their mechanism of action. AS101 is probably the most extensively studied synthetic tellurium compound from the standpoint of its biological activity. It is a potent immunomodulator (both in vitro and in vivo) with a variety of potential therapeutic applications. It is probably the only tellurium compound to be tested in phase I/II clinical studies in cancer patients. The effects of AS101 and SAS are primarily caused by their specific Te(IV) redox-modulating activities enabling the inactivation of cysteine proteases such as cathepsin B, inhibition of specific tumor survival proteins like survivin, or obstruction of tumor IL-10 production. All of these have profound consequences regarding anti-tumor activity or sensitization of tumors to chemotherapy. These properties, coupled with the excellent safety profile of the compounds, suggest promising anti-cancer therapeutic potential for tellurium compounds such as AS101 or SAS.


Assuntos
Antineoplásicos/uso terapêutico , Etilenos/uso terapêutico , Interleucina-10/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Compostos Organometálicos/uso terapêutico , Tartaratos/uso terapêutico , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/uso terapêutico , Animais , Antineoplásicos/farmacologia , Inibidores de Cisteína Proteinase/farmacologia , Inibidores de Cisteína Proteinase/uso terapêutico , Cães , Etilenos/farmacologia , Humanos , Fatores Imunológicos/fisiologia , Imunomodulação/fisiologia , Interleucina-10/metabolismo , Camundongos , Compostos Organometálicos/farmacologia , Ratos , Tartaratos/farmacologia
11.
J Antimicrob Chemother ; 67(9): 2165-72, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22628247

RESUMO

OBJECTIVES: The antibacterial effect of the organo-tellurium compound AS101 on the Gram-negative bacterium Enterobacter cloacae is shown in this study for the first time. METHODS: The antimicrobial effect of the drug was shown by inhibition of growth, by inhibition of biofilm formation and by its ability to penetrate the bacterial cell and to cause damage and ultrastructural changes. RESULTS: AS101 was found to be a bactericidal drug with MICs and MBCs of 9.4 mg/L. It inhibits bacterial growth and causes a six orders of magnitude decrease in viability in a protein-rich medium, but not in a protein-poorer medium, unless 2-mercaptoethanol is added. Subinhibitory concentrations inhibit motility and biofilm formation. AS101 enters the bacterium through its porins and causes bacterial damage to Na(+)/K(+) pumps and leakage of potassium, phosphorous and sulphur. Ultrastructural changes within the bacterial cell and on its surface demonstrate an incomplete surface with a concavity in the centre that looks like a hole from which aggregates are liberated as well as cell lysis. CONCLUSIONS: AS101 has antibacterial activity, which may be useful against E. cloacae and other species of Enterobacteriaceae as a substitute for current antibiotics that have become ineffective due to increasing bacterial resistance.


Assuntos
Antibacterianos/farmacologia , Enterobacter cloacae/efeitos dos fármacos , Etilenos/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Enterobacter cloacae/fisiologia , Enterobacter cloacae/ultraestrutura , Humanos , Testes de Sensibilidade Microbiana , Propriedades de Superfície/efeitos dos fármacos
12.
Leuk Lymphoma ; 62(5): 1146-1156, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33334225

RESUMO

Multiple Myeloma, effectively treated by chemotherapeutic drugs, relapses due to drug resistance. We tested here the capacity of mesenchymal stromal cells, from the bone marrow of patients or from adipose tissue of healthy individuals, to induce drug resistance in Myeloma cell lines. We show that drug resistance can be achieved by factors secreted by the various MSC's. Mass spectrometry analysis of MSC's conditioned media revealed that fibronectin, was particularly instrumental in providing anti-apoptotic signals to MM cells. Moreover, we demonstrate that SAS ([octa-O-bis-(R,R)tartarate ditellurane]), an immunomodulator Tellurium compound, is not only able of blocking the physical interaction between MM cells and fibronectin but is also capable of re-sensitizing the cells to the chemotherapeutic drugs. Finally, we show that this re-sensitization is coupled with the blocking of pAKT induction, in MM cells, by the MSC's. These results indicate that SAS may be useful in the treatment of drug resistant MM.


Assuntos
Mieloma Múltiplo , Preparações Farmacêuticas , Medula Óssea , Resistencia a Medicamentos Antineoplásicos , Humanos , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia , Telúrio/farmacologia
13.
Front Immunol ; 12: 621440, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248930

RESUMO

The risk of severe outcomes following respiratory tract infections is significantly increased in individuals over 60 years, especially in those with chronic medical conditions, i.e., hypertension, diabetes, cardiovascular disease, dementia, chronic respiratory disease, and cancer. Down Syndrome (DS), the most prevalent intellectual disability, is caused by trisomy-21 in ~1:750 live births worldwide. Over the past few decades, a substantial body of evidence has accumulated, pointing at the occurrence of alterations, impairments, and subsequently dysfunction of the various components of the immune system in individuals with DS. This associates with increased vulnerability to respiratory tract infections in this population, such as the influenza virus, respiratory syncytial virus, SARS-CoV-2 (COVID-19), and bacterial pneumonias. To emphasize this link, here we comprehensively review the immunobiology of DS and its contribution to higher susceptibility to severe illness and mortality from respiratory tract infections.


Assuntos
Síndrome de Down/imunologia , Sistema Imunitário/fisiologia , Orthomyxoviridae/fisiologia , Vírus Sinciciais Respiratórios/fisiologia , Infecções Respiratórias/imunologia , SARS-CoV-2/fisiologia , Viroses/imunologia , Adulto , Animais , COVID-19 , Síndrome de Down/genética , Síndrome de Down/mortalidade , Humanos , Pneumonia , Infecções Respiratórias/genética , Infecções Respiratórias/mortalidade , Risco , Viroses/genética , Viroses/mortalidade
14.
Neuromolecular Med ; 23(4): 561-571, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33660221

RESUMO

The current SARS-CoV-2 outbreak, which causes COVID-19, is particularly devastating for individuals with chronic medical conditions, in particular those with Down Syndrome (DS) who often exhibit a higher prevalence of respiratory tract infections, immune dysregulation and potential complications. The incidence of Alzheimer's disease (AD) is much higher in DS than in the general population, possibly increasing further the risk of COVID-19 infection and its complications. Here we provide a biological overview with regard to specific susceptibility of individuals with DS to SARS-CoV-2 infection as well as data from a recent survey on the prevalence of COVID-19 among them. We see an urgent need to protect people with DS, especially those with AD, from COVID-19 and future pandemics and focus on developing protective measures, which also include interventions by health systems worldwide for reducing the negative social effects of long-term isolation and increased periods of hospitalization.


Assuntos
COVID-19/epidemiologia , COVID-19/virologia , Suscetibilidade a Doenças , Síndrome de Down/epidemiologia , Adolescente , Adulto , Doença de Alzheimer/complicações , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/imunologia , COVID-19/complicações , COVID-19/prevenção & controle , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , Comorbidade , Suscetibilidade a Doenças/imunologia , Suscetibilidade a Doenças/virologia , Síndrome de Down/complicações , Síndrome de Down/imunologia , Feminino , Hospitalização , Humanos , Sistema Imunitário/anormalidades , Incidência , Masculino , Pandemias/prevenção & controle , Prevalência , Fatores de Risco , Vacinação/métodos
15.
J Hepatol ; 51(3): 491-503, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19595469

RESUMO

BACKGROUND/AIMS: Fulminant hepatic failure is a dangerous condition, which occurs when large parts of the liver become damaged beyond repair, and the liver is no longer able to function. This syndrome is induced by inflammatory processes, resulting in acute liver failure. Recently, the organotellurium compound, trichloro(dioxoethylene-O,O(')) tellurate (AS101), has been found by our group to be able to directly inhibit caspases, due to its Te(IV)-thiol chemistry. The aim of this study was to examine the potential of AS101 as an anti-inflammatory and anti-apoptotic compound in vitro and in vivo following liver injury. METHODS: Propionibacterium acnes-primed LPS-induced liver injury was performed in Balb/c mice. ALT/AST, cytokines, caspase-1,-3 and-8 activities, and liver histology were assessed. RESULTS: AS101 inhibited TNFalpha or anti-FAS-induced apoptotic processes in hepatocytes in vitro. A P. acnes+LPS in vivo liver injury model revealed lower serum ALT and AST and reduced necrosis and apoptosis in AS101-treated mice. IL-18 and IL-1beta reduced levels in AS101-treated mice were associated with caspase-1 activity inhibition. Our findings suggest IL-6, IL-17 and pSTAT3 as additional novel players in the pathogenicity of FHF. Inhibition of caspase-3, and-8 activities by AS101 treatment contributed to decreased hepatocyte death, resulting in increased survival. CONCLUSIONS: We suggest that due to its interaction with key-target cysteine residues, AS101 mediates anti-inflammatory and anti-apoptotic effects in this FHF model, which may serve as a potent treatment for mitigation of hepatic damage.


Assuntos
Anti-Inflamatórios/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/patologia , Etilenos/uso terapêutico , Hepatite/tratamento farmacológico , Hepatite/patologia , Hepatócitos/patologia , Alanina Transaminase/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Aspartato Aminotransferases/metabolismo , Caspases/metabolismo , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/complicações , Citocinas/metabolismo , Modelos Animais de Doenças , Etilenos/farmacologia , Hepatite/etiologia , Hepatócitos/efeitos dos fármacos , Lipopolissacarídeos/efeitos adversos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Falência Hepática/metabolismo , Falência Hepática/patologia , Camundongos , Camundongos Endogâmicos BALB C , Resultado do Tratamento
16.
Arch Microbiol ; 191(8): 631-8, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19529918

RESUMO

Due to the extensive spread of antibiotic-resistant Klebsiella pneumoniae, the non-toxic immunomodulator, ammonium trichloro (dioxoethylene-o, o') tellurate (AS101), was introduced for the first time in this study. Eleven strains of K. pneumoniae were tested: five were extended spectrum beta lactamase (ESBL)-producing strains and six were non-ESBL-producing strains. The MIC and MBC of ten strains were 9 microg/ml AS101 and 18 microg/ml for one strain. AS101 treatment inhibited bacterial growth in a dose-dependent manner on protein-rich media. No inhibition by AS101 was observed on poorer media. In combination with beta-mercaptoethanol (2-ME) or cysteamine, AS101 inhibited bacterial growth in both types of media. Growth inhibition was also shown following AS101 treatment at both lag and log phases. Our data indicate that AS101 enters the bacterium through its porins, causing bacterial destruction. The mechanism of cell death was characterized using several techniques: (a) scanning electron microscopy showed that bacteria treated with AS101 or in combination with cysteamine exhibited evidence of cell-wall damage; (b) X-ray microanalysis demonstrated damage to Na/K pumps; and (c) transmission electron microscopy demonstrated cell lysis. These phenomena suggest that AS101 has antibacterial potential against K. pneumoniae infections.


Assuntos
Antibacterianos/farmacologia , Etilenos/farmacologia , Klebsiella pneumoniae/efeitos dos fármacos , beta-Lactamases/metabolismo , Bacteriólise , Parede Celular/efeitos dos fármacos , Meios de Cultura , Cisteamina/farmacologia , Klebsiella pneumoniae/crescimento & desenvolvimento , Klebsiella pneumoniae/metabolismo , Mercaptoetanol/farmacologia , Testes de Sensibilidade Microbiana , Porinas/metabolismo
17.
Nephrol Dial Transplant ; 24(8): 2328-38, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19321762

RESUMO

BACKGROUND: Compensatory tubular cell hypertrophy following unilateral nephrectomy is a cell cycle-dependent process. Our previous study showed that treatment of unilaterally nephrectomized rats with the immunomodulator AS101 partially inhibits compensatory hypertrophy of the remaining kidneys through the inhibition of IL-10-induced TGF-beta secretion by mesangial cells. The present study is focused on understanding the intracellular mechanism(s) of this phenomenon. METHODS: A total of 120 male Sprague-Dawley rats were unilaterally nephrectomized or sham-operated and treated with AS101 or PBS. Kidney weight and protein/DNA ratio were assessed for each experimental animal. The expression of TGF-beta, PCNA, CDK 2, pRb, ppRb, p21(Waf1), p27(kip1) and p57(kip2) proteins in renal tissues was determined by western blot analysis and immunohistochemistry, and the immunoprecipitation of cyclin E complexes was performed. RESULTS: Compensatory renal growth is initiated by proliferation of resident renal cells that precedes hypertrophy. Changes in TGF-beta expression were positively correlated with the amounts of p57(kip2), but not with p21(Waf1) and p27(kip1) expression in the remaining kidneys. Moreover, there was a marked abundance of p57(kip2) but not p21(Waf1) and p27(kip1) binding to the cyclin E complex in PBS-treated unilaterally nephrectomized rats compared to sham-operated animals. Treatment of uninephrectomized rats with AS101 reduced kidney weight and protein/DNA ratio, inhibited TGF-beta and p57(kip2) expression in the remaining kidneys, and decreased the level of p57(kip2) binding to cyclin E complexes. CONCLUSION: These results demonstrate that TGF-beta-induced compensatory tubular cell hypertrophy is regulated in vivo by p57(kip2) but not by the p21(Waf1) and p27(kip1) cyclin kinase inhibitor proteins.


Assuntos
Adjuvantes Imunológicos/farmacologia , Inibidor de Quinase Dependente de Ciclina p57/metabolismo , Etilenos/farmacologia , Túbulos Renais/patologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Western Blotting , Células Cultivadas , Ciclina E/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , DNA/metabolismo , Regulação da Expressão Gênica , Hipertrofia , Técnicas Imunoenzimáticas , Imunoprecipitação , Interleucina-10/metabolismo , Túbulos Renais/metabolismo , Masculino , Nefrectomia , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína do Retinoblastoma/metabolismo
18.
Semin Cancer Biol ; 22(1): 1-2, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22240249
19.
ACS Appl Bio Mater ; 2(5): 2246-2251, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35030663

RESUMO

The in vivo delivery of therapeutic nanoparticles (NPs) represents a potentially powerful tool that can significantly alter the biological effects of pharmaceutically active compounds. Here, we report on sensitization of tumors to chemotherapy by ammonium trichloro(dioxoethylene-o,o')tellurate (AS101) encapsulated in NPs, termed AS101-NPs, developed as a composite with the biocompatible and biodegradable copolymer of poly(d,l-lactic-co-glycolic acid)-block-poly(ethylene glycol) (PLGA-b-PEG). AS101 is a potent immunomodulating agent (both in vitro and in vivo) currently undergoing phase II clinical trials for antitumor activity and sensitization of tumors to chemotherapy. Approaches that can control the pharmacokinetic parameters to regulate its clearance from the administered drug delivery system and minimize side effects are of prodigious importance. A strategy to synthesize AS101-NPs by nanoprecipitation is presented, along with their physical characterization. The influence of AS101 encapsulation on its properties was evaluated in vivo. The AS101-NPs demonstrated a significantly enhanced peritoneal macrophage count compared with AS101 administered in vivo at a conventional dosage in mouse models. Moreover, AS101 inhibited B16 melanoma lung metastasis in mice when given intraperitoneally, before or after tumor cell inoculation. A bell-shaped dose-response was observed. The frequency of AS101 administration appears to be an important factor for achieving an optimal antimetastatic effect.

20.
Front Immunol ; 10: 979, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191514

RESUMO

The study shows that treatment of NOD mice with either of two tellurium-based small molecules, AS101 [ammonium trichloro(dioxoethylene-o,o')tellurate] or SAS [octa-O-bis-(R,R)-tartarate ditellurane] could preserve ß cells function and mass. These beneficial effects were reflected in decreased incidence of diabetes, improved glucose clearance, preservation of body weight, and increased survival. The normal glucose levels were associated with increased insulin levels, preservation of ß cell mass and increased islet size. Importantly, this protective activity could be demonstrated when the compounds were administered either at the early pre-diabetic phase with no or initial insulitis, at the pre-diabetic stage with advanced insulitis, or even at the advanced, overtly diabetic stage. We further demonstrate that both tellurium compounds prevent migration of autoimmune lymphocytes to the pancreas, via inhibition of the α4ß7 integrin activity. Indeed, the decreased migration resulted in diminished pancreatic islets damage both with respect to their size, ß cell function, and caspase-3 activity, the hallmark of apoptosis. Most importantly, AS101 and SAS significantly elevated the number of T regulatory cells in the pancreas, thus potentially controlling the autoimmune process. We show that the compounds inhibit pancreatic caspase-1 activity followed by decreased levels of the inflammatory cytokines IL-1ß and IL-17 in the pancreas. These properties enable the compounds to increase the proportion of Tregs in the pancreatic lymph nodes. AS101 and SAS have been previously shown to regulate specific integrins through a unique redox mechanism. Our current results suggest that amelioration of disease in NOD mice by this unique mechanism is due to decreased infiltration of pancreatic islets combined with increased immune regulation, leading to decreased inflammation within the islets. As these tellurium compounds show remarkable lack of toxicity in clinical trials (AS101) and pre-clinical studies (SAS), they may be suitable for the treatment of type-1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Etilenos/uso terapêutico , Integrinas/antagonistas & inibidores , Interleucina-1beta/antagonistas & inibidores , Linfócitos T Reguladores/efeitos dos fármacos , Animais , Diabetes Mellitus Tipo 1/imunologia , Etilenos/farmacologia , Feminino , Integrinas/fisiologia , Interleucina-1beta/fisiologia , Camundongos , Camundongos Endogâmicos NOD , Pancreatite/tratamento farmacológico , Células Th17/fisiologia
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