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1.
Artigo em Inglês | MEDLINE | ID: mdl-36754834

RESUMO

BACKGROUND AND OBJECTIVES: Myasthenia gravis (MG) can in rare cases be an autoimmune phenomenon associated with hematologic malignancies such as chronic lymphocytic leukemia (CLL). It is unclear whether in patients with MG and CLL, the leukemic B cells are the ones directly driving the autoimmune response against neuromuscular endplates. METHODS: We identified patients with acetylcholine receptor antibody-positive (AChR+) MG and CLL or monoclonal B-cell lymphocytosis (MBL), a precursor to CLL, and described their clinical features, including treatment responses. We generated recombinant monoclonal antibodies (mAbs) corresponding to the B-cell receptors of the CLL phenotype B cells and screened them for autoantigen binding. RESULTS: A computational immune cell screen revealed a subgroup of 5/38 patients with MG and 0/21 healthy controls who displayed a CLL-like B-cell phenotype. In follow-up hematologic flow cytometry, 2 of these 5 patients were diagnosed with an MBL. An additional patient with AChR+ MG as a complication of manifest CLL presented at our neuromuscular clinic and was successfully treated with the anti-CD20 therapy obinutuzumab plus chlorambucil. We investigated the specificities of expanding CLL-like B-cell clones to assess a direct causal link between the 2 diseases. However, we observed no reactivity of the clones against the AChR, antigens at the neuromuscular junction, or other common autoantigens. DISCUSSION: Our study suggests that AChR autoantibodies are produced by nonmalignant, polyclonal B cells The new anti-CD20 treatment obinutuzumab might be considered in effectively treating AChR+ MG. CLASSIFICATION OF EVIDENCE: This is a single case study and provides Class IV evidence that obinutuzumab is safe to use in patients with MG.


Assuntos
Leucemia Linfocítica Crônica de Células B , Miastenia Gravis , Humanos , Leucemia Linfocítica Crônica de Células B/complicações , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Miastenia Gravis/complicações , Receptores Colinérgicos , Linfócitos B , Anticorpos Monoclonais , Autoanticorpos , Autoantígenos
2.
Front Immunol ; 13: 804822, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35514991

RESUMO

Based on the epidemiological link between periodontitis and rheumatoid arthritis (RA), and the unique feature of the periodontal bacterium Porphyromonas gingivalis to citrullinate proteins, it has been suggested that production of anti-citrullinated protein antibodies (ACPA), which are present in a majority of RA patients, may be triggered in the gum mucosa. To address this hypothesis, we investigated the antibody response to a citrullinated P. gingivalis peptide in relation to the autoimmune ACPA response in early RA, and examined citrulline-reactivity in monoclonal antibodies derived from human gingival B cells. Antibodies to a citrullinated peptide derived from P. gingivalis (denoted CPP3) and human citrullinated peptides were analyzed by multiplex array in 2,807 RA patients and 372 controls; associations with RA risk factors and clinical features were examined. B cells from inflamed gingival tissue were single-cell sorted, and immunoglobulin (Ig) genes were amplified, sequenced, cloned and expressed (n=63) as recombinant monoclonal antibodies, and assayed for citrulline-reactivities by enzyme-linked immunosorbent assay. Additionally, affinity-purified polyclonal anti-cyclic-citrullinated peptide (CCP2) IgG, and monoclonal antibodies derived from RA blood and synovial fluid B cells (n=175), were screened for CPP3-reactivity. Elevated anti-CPP3 antibody levels were detected in RA (11%), mainly CCP2+ RA, compared to controls (2%), p<0.0001, with a significant association to HLA-DRB1 shared epitope alleles, smoking and baseline pain, but with low correlation to autoimmune ACPA fine-specificities. Monoclonal antibodies derived from gingival B cells showed cross-reactivity between P. gingivalis CPP3 and human citrullinated peptides, and a CPP3+/CCP2+ clone, derived from an RA blood memory B cell, was identified. Our data support the possibility that immunity to P. gingivalis derived citrullinated antigens, triggered in the inflamed gum mucosa, may contribute to the presence of ACPA in RA patients, through mechanisms of molecular mimicry.


Assuntos
Artrite Reumatoide , Porphyromonas gingivalis , Anticorpos Monoclonais , Autoanticorpos , Citrulina , Epitopos , Humanos , Imunoglobulina G , Peptídeos
3.
J Pers Med ; 13(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36675726

RESUMO

A palatal fistula is a pathological condition that connects the nasal cavities with the oral cavity. An oral-nasal fistula is reported as a possible post-surgical complication after the removal of oral carcinomas. The presence of a palatal fistula affects the patient's quality of life, making it necessary to apply a prosthetic device, such as a palatal plate, to keep the nasal cavities separated from the oral one. There are several surgical techniques to close a palatal fistula, but it is not possible to define the optimal technique as the approach is extremely dependent on the characteristics of the fistula. The aim of this article is to propose a minimally invasive technique to reduce the size of palatal fistulae and to reduce the surgical difficulty (NSPF). A total of 20 patients fulfilled the inclusion criteria and were checked every two weeks. The fistula was injured with a needle every 2 weeks. Fifteen patients who healed with complete closure of the fistula reported no need for a palatal protection plate to eat, drink and speak normally. It is possible to conclude that the NSPF protocol is a valid approach for the non-surgical reduction of palatal fistulae, and it is possible, when the appropriate conditions are present, to achieve complete closure.

4.
J Health Econ ; 80: 102546, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34731726

RESUMO

This paper addresses one of the main empirical problems associated with rational addiction theory, namely, that its derived demand equation is not empirically distinguishable from those of models with forward-looking behavior but with time-inconsistent preferences. Using an encompassing general specification of the rational addiction model we derive a microfounded test of time-consistency. The test allows us to distinguish between time-consistent versus time-inconsistent naïve agents. The results obtained from a panel of Russian individuals conform to the theoretical predictions of the rational addiction model and the proposed test for time-consistency does not reject the hypothesis that Russian cigarette consumers are time-consistent.


Assuntos
Comportamento Aditivo , Comportamento Aditivo/diagnóstico , Comportamento Aditivo/epidemiologia , Humanos , Federação Russa
5.
Front Immunol ; 12: 627986, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093522

RESUMO

Seropositive rheumatoid arthritis (RA) is characterized by the presence of rheumatoid factor (RF) and anti-citrullinated protein autoantibodies (ACPA) with different fine-specificities. Yet, other serum anti-modified protein autoantibodies (AMPA), e.g. anti-carbamylated (Carb), -acetylated (KAc), and malondialdehyde acetaldehyde (MAA) modified protein antibodies, have been described. In this comprehensive study, we analyze 30 different IgG and IgA AMPA reactivities to Cit, Carb, KAc, and MAA antigens detected by ELISA and autoantigen arrays in N=1985 newly diagnosed RA patients. Association with patient characteristics such as smoking and disease activity were explored. Carb and KAc reactivities by different assays were primarily seen in patients also positive for anti-citrulline reactivity. Modified vimentin (mod-Vim) peptides were used for direct comparison of different AMPA reactivities, revealing that IgA AMPA recognizing mod-Vim was mainly detected in subsets of patients with high IgG anti-Cit-Vim levels and a history of smoking. IgG reactivity to acetylation was mainly detected in a subset of patients with Cit and Carb reactivity. Anti-acetylated histone reactivity was RA-specific and associated with high anti-CCP2 IgG levels, multiple ACPA fine-specificities, and smoking status. This reactivity was also found to be present in CCP2+ RA-risk individuals without arthritis. Our data further demonstrate that IgG autoreactivity to MAA was increased in RA compared to controls with highest levels in CCP2+ RA, but was not RA-specific, and showed low correlation with other AMPA. Anti-MAA was instead associated with disease activity and was not significantly increased in CCP2+ individuals at risk of RA. Notably, RA patients could be subdivided into four different subsets based on their AMPA IgG and IgA reactivity profiles. Our serology results were complemented by screening of monoclonal antibodies derived from single B cells from RA patients for the same antigens as the RA cohort. Certain CCP2+ clones had Carb or Carb+KAc+ multireactivity, while such reactivities were not found in CCP2- clones. We conclude that autoantibodies exhibiting different patterns of ACPA fine-specificities as well as Carb and KAc reactivity are present in RA and may be derived from multireactive B-cell clones. Carb and KAc could be considered reactivities within the "Cit-umbrella" similar to ACPA fine-specificities, while MAA reactivity is distinctly different.


Assuntos
Artrite Reumatoide/imunologia , Autoanticorpos/sangue , Autoantígenos/imunologia , Autoimunidade , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Processamento de Proteína Pós-Traducional , Acetilação , Adulto , Idoso , Anticorpos Antiproteína Citrulinada/sangue , Especificidade de Anticorpos , Artrite Reumatoide/sangue , Artrite Reumatoide/diagnóstico , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Malondialdeído/imunologia , Pessoa de Meia-Idade , Peptídeos Cíclicos/imunologia , Carbamilação de Proteínas
6.
Nat Commun ; 12(1): 3532, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112780

RESUMO

In systemic light chain amyloidosis (AL), pathogenic monoclonal immunoglobulin light chains (LC) form toxic aggregates and amyloid fibrils in target organs. Prompt diagnosis is crucial to avoid permanent organ damage, but delayed diagnosis is common because symptoms usually appear only after strong organ involvement. Here we present LICTOR, a machine learning approach predicting LC toxicity in AL, based on the distribution of somatic mutations acquired during clonal selection. LICTOR achieves a specificity and a sensitivity of 0.82 and 0.76, respectively, with an area under the receiver operating characteristic curve (AUC) of 0.87. Tested on an independent set of 12 LCs sequences with known clinical phenotypes, LICTOR achieves a prediction accuracy of 83%. Furthermore, we are able to abolish the toxic phenotype of an LC by in silico reverting two germline-specific somatic mutations identified by LICTOR, and by experimentally assessing the loss of in vivo toxicity in a Caenorhabditis elegans model. Therefore, LICTOR represents a promising strategy for AL diagnosis and reducing high mortality rates in AL.


Assuntos
Caenorhabditis elegans/metabolismo , Cadeias Leves de Imunoglobulina/genética , Cadeias Leves de Imunoglobulina/toxicidade , Amiloidose de Cadeia Leve de Imunoglobulina/diagnóstico , Amiloidose de Cadeia Leve de Imunoglobulina/genética , Aprendizado de Máquina , Algoritmos , Sequência de Aminoácidos , Animais , Anticorpos/genética , Caenorhabditis elegans/genética , Bases de Dados Genéticas , Expressão Gênica , Humanos , Cadeias Leves de Imunoglobulina/química , Modelos Moleculares , Mutação , Proteínas Recombinantes
7.
Nature ; 592(7855): 639-643, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33790470

RESUMO

Some Plasmodium falciparum repetitive interspersed families of polypeptides (RIFINs)-variant surface antigens that are expressed on infected erythrocytes1-bind to the inhibitory receptor LAIR1, and insertion of DNA that encodes LAIR1 into immunoglobulin genes generates RIFIN-specific antibodies2,3. Here we address the general relevance of this finding by searching for antibodies that incorporate LILRB1, another inhibitory receptor that binds to ß2 microglobulin and RIFINs through their apical domains4,5. By screening plasma from a cohort of donors from Mali, we identified individuals with LILRB1-containing antibodies. B cell clones isolated from three donors showed large DNA insertions in the switch region that encodes non-apical LILRB1 extracellular domain 3 and 4 (D3D4) or D3 alone in the variable-constant (VH-CH1) elbow. Through mass spectrometry and binding assays, we identified a large set of RIFINs that bind to LILRB1 D3. Crystal and cryo-electron microscopy structures of a RIFIN in complex with either LILRB1 D3D4 or a D3D4-containing antibody Fab revealed a mode of RIFIN-LILRB1 D3 interaction that is similar to that of RIFIN-LAIR1. The Fab showed an unconventional triangular architecture with the inserted LILRB1 domains opening up the VH-CH1 elbow without affecting VH-VL or CH1-CL pairing. Collectively, these findings show that RIFINs bind to LILRB1 through D3 and illustrate, with a naturally selected example, the general principle of creating novel antibodies by inserting receptor domains into the VH-CH1 elbow.


Assuntos
Anticorpos/química , Anticorpos/imunologia , Antígenos de Protozoários/química , Antígenos de Protozoários/imunologia , Microscopia Crioeletrônica , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/química , Plasmodium falciparum/química , Plasmodium falciparum/imunologia , Adolescente , Adulto , Sequência de Aminoácidos , Anticorpos/ultraestrutura , Especificidade de Anticorpos , Antígenos de Protozoários/ultraestrutura , Sítios de Ligação de Anticorpos , Criança , Pré-Escolar , Estudos de Coortes , Humanos , Lactente , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/imunologia , Mali , Modelos Moleculares , Plasmodium falciparum/genética , Plasmodium falciparum/ultraestrutura , Domínios Proteicos , Adulto Jovem
8.
Acta Neuropathol ; 141(6): 901-915, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33774709

RESUMO

Myasthenia gravis (MG) is an autoimmune disease characterized by impaired neuromuscular signaling due to autoantibodies targeting the acetylcholine receptor. Although its auto-antigens and effector mechanisms are well defined, the cellular and molecular drivers underpinning MG remain elusive. Here, we employed high-dimensional single-cell mass and spectral cytometry of blood and thymus samples from MG patients in combination with supervised and unsupervised machine-learning tools to gain insight into the immune dysregulation underlying MG. By creating a comprehensive immune map, we identified two dysregulated subsets of inflammatory circulating memory T helper (Th) cells. These signature ThCD103 and ThGM cells populated the diseased thymus, were reduced in the blood of MG patients, and were inversely correlated with disease severity. Both signature Th subsets rebounded in the blood of MG patients after surgical thymus removal, indicative of their role as cellular markers of disease activity. Together, this in-depth analysis of the immune landscape of MG provides valuable insight into disease pathogenesis, suggests novel biomarkers and identifies new potential therapeutic targets for treatment.


Assuntos
Imunofenotipagem/métodos , Miastenia Gravis/imunologia , Miastenia Gravis/patologia , Análise de Célula Única , Linfócitos T/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos , Autoimunidade , Linfócitos B/imunologia , Biomarcadores , Feminino , Humanos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/sangue , Receptores Colinérgicos/imunologia , Linfócitos T/imunologia , Timectomia , Timo
9.
Nat Med ; 25(9): 1402-1407, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501610

RESUMO

Natalizumab (NZM), a humanized monoclonal IgG4 antibody to α4 integrins, is used to treat patients with relapsing-remitting multiple sclerosis (MS)1,2, but in about 6% of the cases persistent neutralizing anti-drug antibodies (ADAs) are induced leading to therapy discontinuation3,4. To understand the basis of the ADA response and the mechanism of ADA-mediated neutralization, we performed an in-depth analysis of the B and T cell responses in two patients. By characterizing a large panel of NZM-specific monoclonal antibodies, we found that, in both patients, the response was polyclonal and targeted different epitopes of the NZM idiotype. The neutralizing activity was acquired through somatic mutations and correlated with a slow dissociation rate, a finding that was supported by structural data. Interestingly, in both patients, the analysis of the CD4+ T cell response, combined with mass spectrometry-based peptidomics, revealed a single immunodominant T cell epitope spanning the FR2-CDR2 region of the NZM light chain. Moreover, a CDR2-modified version of NZM was not recognized by T cells, while retaining binding to α4 integrins. Collectively, our integrated analysis identifies the basis of T-B collaboration that leads to ADA-mediated therapeutic resistance and delineates an approach to design novel deimmunized antibodies for autoimmune disease and cancer treatment.


Assuntos
Anticorpos Neutralizantes/administração & dosagem , Epitopos de Linfócito T/imunologia , Esclerose Múltipla/tratamento farmacológico , Natalizumab/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Neutralizantes/química , Formação de Anticorpos/efeitos dos fármacos , Formação de Anticorpos/imunologia , Linfócitos B/efeitos dos fármacos , Humanos , Imunoglobulina G/química , Imunoglobulina G/imunologia , Integrina alfa4/antagonistas & inibidores , Integrina alfa4/imunologia , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Conformação Proteica/efeitos dos fármacos , Linfócitos T/química , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
10.
Stem Cells Dev ; 28(10): 695-706, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30887879

RESUMO

Dental pulp has been revealed as an accessible and a rich source of mesenchymal stem cells (MSCs) and its biological potential is currently under intense investigation. MSCs from dental pulp stem cells (DPSCs) have been indicated as a heterogeneous population oriented not only in repairing dentine but also in maintaining vascular and nervous homeostasis of the teeth. We sought to verify the phenotype of cells isolated from dental pulp of young donors and to investigate in vitro their role as pericyte-like cells. Specifically, we evaluated how culture conditions can modulate expression of pericyte markers in DPSCs and their capacity to stabilize endothelial tubes in vitro. DPSCs cultured in standard conditions expressed MSC markers and demonstrated to contain a population expressing the pericyte marker NG2. These DPSCs were associated with low sprouting capacity in extra-cellular (EC) Matrix and limited ability in retaining tubes formed by endothelial cells in a coculture angiogenesis model. When cultured in endothelial growth medium (EGM)-2, DPSCs significantly upregulated NG2, and partially alpha-smooth muscle actin. The resulting population conserved the stem marker CD73, but was negative for calponin and endothelial markers. EGM-2-conditioned DPSCs showed a higher sprouting ability in EC Matrix and efficient association with human umbilical vein endothelial cells allowing the partial retention of endothelial tubes for several days. Among growth factors contained in EGM-2 we identified basic fibroblast growth factor (bFGF) as mainly responsible for NG2 upregulation and long-term stabilization of endothelial tubes. According to the in vitro analysis, DPSCs represent an effective source of pericytes and the appropriate culture conditions could result in a population with a promising ability to stabilize vessels and promote vascular maturation.


Assuntos
Polpa Dentária/citologia , Dentina/citologia , Células Endoteliais da Veia Umbilical Humana/fisiologia , Células-Tronco Mesenquimais/citologia , Pericitos/citologia , 5'-Nucleotidase/metabolismo , Antígenos/metabolismo , Diferenciação Celular/fisiologia , Proteínas Ligadas por GPI/metabolismo , Humanos , Pericitos/fisiologia , Proteoglicanas/metabolismo
11.
Int J Mol Sci ; 20(2)2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30654447

RESUMO

Human Dental Pulp Stem Cells (hDPSCs) represent a type of adult mesenchymal stem cells that have the ability to differentiate in vitro in several lineages such as odontoblasts, osteoblasts, chondrocytes, adipocytes and neurons. In the current work, we used hDPSCs as the experimental model to study the role of recombinant prion protein 23⁻231 (recPrPC) in the neuronal differentiation process, and in the signal pathway activation of ERK 1/2 and Akt. We demonstrated that recPrPC was able to activate an intracellular signal pathway mediated by extracellular-signal-regulated kinase 1 and 2 (ERK 1/2) and protein kinase B (Akt). Moreover, in order to understand whether endogenous prion protein (PrPC) was necessary to mediate the signaling induced by recPrPC, we silenced PrPC, demonstrating that the presence of endogenous PrPC was essential for ERK 1/2 and Akt phosphorylation. Since endogenous PrPC is a well-known lipid rafts component, we evaluated the role of these structures in the signal pathway induced by recPrPC. Our results suggest that lipid rafts integrity play a key role in recPrPC activity. In fact, lipid rafts inhibitors, such as fumonisin B1 and MßCD, significantly prevented ERK 1/2 and Akt phosphorylation induced by recPrPC. In addition, we investigated the capacity of recPrPC to induce hDPSCs neuronal differentiation process after long-term stimulation through the evaluation of typical neuronal markers expression such as B3-Tubulin, neurofilament-H (NFH) and growth associated protein 43 (GAP43). Accordingly, when we silenced endogenous PrPC, we observed the inhibition of neuronal differentiation induced by recPrPC. The combined data suggest that recPrPC plays a key role in the neuronal differentiation process and in the activation of specific intracellular signal pathways in hDPSCs.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Neurônios/citologia , Fragmentos de Peptídeos/farmacologia , Príons/farmacologia , Proteínas Recombinantes/farmacologia , Adolescente , Biomarcadores/metabolismo , Polpa Dentária/citologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Inativação Gênica/efeitos dos fármacos , Humanos , Microdomínios da Membrana/efeitos dos fármacos , Microdomínios da Membrana/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Adulto Jovem
12.
Prion ; 12(2): 117-126, 2018 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-29644924

RESUMO

Cellular prion protein (PrPC) is expressed in a wide variety of stem cells in which regulates their self-renewal as well as differentiation potential. In this study we investigated the presence of PrPC in human dental pulp-derived stem cells (hDPSCs) and its role in neuronal differentiation process. We show that hDPSCs expresses early PrPC at low concentration and its expression increases after two weeks of treatment with EGF/bFGF. Then, we analyzed the association of PrPC with gangliosides and EGF receptor (EGF-R) during neuronal differentiation process. PrPC associates constitutively with GM2 in control hDPSCs and with GD3 only after neuronal differentiation. Otherwise, EGF-R associates weakly in control hDPSCs and more markedly after neuronal differentiation. To analyze the functional role of PrPC in the signal pathway mediated by EGF/EGF-R, a siRNA PrP was applied to ablate PrPC and its function. The treatment with siRNA PrP significantly prevented Akt and ERK1/2 phosphorylation induced by EGF. Moreover, siRNA PrP treatment significantly prevented neuronal-specific antigens expression induced by EGF/bFGF, indicating that cellular prion protein is essential for EGF/bFGF-induced hDPSCs differentiation. These results suggest that PrPC interact with EGF-R within lipid rafts, playing a role in the multimolecular signaling complexes involved in hDPSCs neuronal differentiation.


Assuntos
Polpa Dentária/citologia , Neurônios/citologia , Neurônios/metabolismo , Proteínas Priônicas/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Proteínas Priônicas/genética , RNA Interferente Pequeno/genética
13.
J Int Soc Prev Community Dent ; 6(2): 97-104, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27114946

RESUMO

Medication-related osteonecrosis of the jaw (MRONJ) is a severe adverse drug reaction, consisting of progressive bone destruction in the maxillofacial region of patients. ONJ can be caused by two pharmacological agents: Antiresorptive (including bisphosphonates (BPs) and receptor activator of nuclear factor kappa-B ligand inhibitors) and antiangiogenic. MRONJ pathophysiology is not completely elucidated. There are several suggested hypothesis that could explain its unique localization to the jaws: Inflammation or infection, microtrauma, altered bone remodeling or over suppression of bone resorption, angiogenesis inhibition, soft tissue BPs toxicity, peculiar biofilm of the oral cavity, terminal vascularization of the mandible, suppression of immunity, or Vitamin D deficiency. Dental screening and adequate treatment are fundamental to reduce the risk of osteonecrosis in patients under antiresorptive or antiangiogenic therapy, or before initiating the administration. The treatment of MRONJ is generally difficult and the optimal therapy strategy is still to be established. For this reason, prevention is even more important. It is suggested that a multidisciplinary team approach including a dentist, an oncologist, and a maxillofacial surgeon to evaluate and decide the best therapy for the patient. The choice between a conservative treatment and surgery is not easy, and it should be made on a case by case basis. However, the initial approach should be as conservative as possible. The most important goals of treatment for patients with established MRONJ are primarily the control of infection, bone necrosis progression, and pain. The aim of this paper is to represent the current knowledge about MRONJ, its preventive measures and management strategies.

14.
Am J Trop Med Hyg ; 94(1): 166-71, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26503271

RESUMO

Knowledge of variables influencing serology is crucial to evaluate serology results for the diagnosis and clinical management of cystic echinococcosis (CE). We analyzed retrospectively a cohort of patients with hepatic CE followed in our clinic in 2000-2012 to evaluate the influence of several variables on the results of commercial enzyme-linked immunosorbent assay (ELISA) and indirect hemagglutination (IHA) tests. Sera from 171 patients with ≥ 1 hepatic CE cyst, and 90 patients with nonparasitic cysts were analyzed. CE cysts were staged according to the WHO-IWGE classification and grouped by activity. A significant difference in ELISA optical density (OD) values and percentage of positivity was found among CE activity groups and with controls (P < 0.001). The serological response was also influenced by age (P < 0.001) and cyst number (P = 0.003). OD values and cyst size were positively correlated in active cysts (P = 0.001). IHA test showed comparable results. When we analyzed the results of 151 patients followed over time, we found that serology results were significantly influenced by cyst activity, size, number, and treatment ≤ 12 months before serum collection. In conclusion, serological responses as assessed by commercial tests depend on CE cyst activity, size and number, and time from treatment. Clinical studies and clinicians in their practice should take this into account.


Assuntos
Equinococose Hepática/sangue , Adulto , Idoso , Anti-Helmínticos/uso terapêutico , Estudos de Casos e Controles , Estudos Transversais , Equinococose Hepática/tratamento farmacológico , Ensaio de Imunoadsorção Enzimática , Feminino , Testes de Hemaglutinação , Humanos , Masculino , Pessoa de Meia-Idade
15.
Exp Cell Res ; 339(2): 231-40, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26586565

RESUMO

Human dental pulp-derived stem cells (hDPSCs) are characterized by a typical fibroblast-like morphology. They express specific markers for mesenchymal stem cells and are capable of differentiation into osteoblasts, adipoblasts and neurons in vitro. Previous studies showed that gangliosides are involved in the induction of early neuronal differentiation of hDPSCs. This study was undertaken to investigate the role of lipid rafts in this process. Lipid rafts are signaling microdomains enriched in glycosphingolipids, cholesterol, tyrosine kinase receptors, mono- or heterotrimeric G proteins and GPI-anchored proteins. We preliminary showed that established cells expressed multipotent mesenchymal stromal-specific surface antigens. Then, we analyzed the distribution of lipid rafts, revealing plasma membrane microdomains with GM2 and EGF-R enrichment. Following stimulation with EGF/bFGF, neuronal differentiation was observed. To analyze the functional role of lipid rafts in EGF/bFGF-induced hDPSCs differentiation, cells were preincubated with lipid raft affecting agents, i.e. [D]-PDMP or methyl-ß-cyclodextrin. These compounds significantly prevented neuronal-specific antigen expression, as well as Akt and ERK 1/2 phosphorylation, induced by EGF/bFGF, indicating that lipid raft integrity is essential for EGF/bFGF-induced hDPSCs differentiation. These results suggest that lipid rafts may represent specific chambers, where multimolecular signaling complexes, including lipids (gangliosides, cholesterol) and proteins (EGF-R), play a role in hDPSCs differentiation.


Assuntos
Diferenciação Celular , Polpa Dentária/citologia , Microdomínios da Membrana/metabolismo , Células-Tronco Mesenquimais/citologia , Neurônios/citologia , Humanos , Neurônios/metabolismo
16.
Nat Commun ; 6: 7375, 2015 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-26077231

RESUMO

Pulmonary alveolar proteinosis (PAP) is a severe autoimmune disease caused by autoantibodies that neutralize GM-CSF resulting in impaired function of alveolar macrophages. In this study, we characterize 21 GM-CSF autoantibodies from PAP patients and find that somatic mutations critically determine their specificity for the self-antigen. Individual antibodies only partially neutralize GM-CSF activity using an in vitro bioassay, depending on the experimental conditions, while, when injected in mice together with human GM-CSF, they lead to the accumulation of a large pool of circulating GM-CSF that remains partially bioavailable. In contrast, a combination of three non-cross-competing antibodies completely neutralizes GM-CSF activity in vitro by sequestering the cytokine in high-molecular-weight complexes, and in vivo promotes the rapid degradation of GM-CSF-containing immune complexes in an Fc-dependent manner. Taken together, these findings provide a plausible explanation for the severe phenotype of PAP patients and for the safety of treatments based on single anti-GM-CSF monoclonal antibodies.


Assuntos
Anticorpos Neutralizantes/imunologia , Autoanticorpos/imunologia , Doenças Autoimunes/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Proteinose Alveolar Pulmonar/imunologia , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Ensaio de Imunoadsorção Enzimática , Epitopos/genética , Feminino , Humanos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Receptores de IgG/imunologia
17.
PLoS Negl Trop Dis ; 8(8): e3057, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25122222

RESUMO

Human cystic echinococcosis is a chronic, complex and neglected infection. Its clinical management has evolved over decades without adequate evaluation of efficacy. Recent expert opinion recommends that uncomplicated inactive cysts of the liver should be left untreated and solely monitored over time ("watch-and-wait" approach). However, clinical data supporting this approach are still scant and published mostly as conference proceedings. In this study, we report our experience with long-term sonographic and serological follow-up of inactive cysts of the liver. From March 1994 to October 2013, 38 patients with 47 liver cysts, diagnosed as inactive without any previous treatment history, were followed with ultrasound and serology at 6-12 months intervals for a period of at least 24 months (median follow-up 51.95 months) in our outpatient clinic. In 97.4% of patients, the cysts remained inactive over time and in only one case was reactivation of the cyst detected. No complications occurred during the time of monitoring. During follow-up, serology tests for CE were negative at diagnosis or became negative in 74.1% and were positive or became positive in 25.9% of cases. Patients with inactive cysts on ultrasound but positive serological tests were also investigated by CT scan (chest and abdomen) to rule out extra-hepatic cyst localization. This study confirms the importance of a stage-specific approach to the management of cystic echinococcosis and supports the use of a monitoring-only approach to inactive, uncomplicated cysts of the liver. It also confirms that serology plays only an ancillary role in the clinical management of these patients, compared to ultrasound and other imaging techniques. The implications of these findings for clinical management and natural history of cystic echinococcosis are discussed.


Assuntos
Cistos/diagnóstico , Equinococose Hepática/diagnóstico , Abdome/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Equinococose Hepática/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Testes Sorológicos , Tomografia Computadorizada por Raios X , Ultrassonografia
18.
Ann Stomatol (Roma) ; 5(4): 136-41, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25774249

RESUMO

AIM: The aim of this study is to present 18 months follow-up results of porous tantalum trabecular metal-enhanced titanium dental implant (PTTM) in implant supported prosthesis in post-oncological patients. MATERIALS AND METHODS: A total of 25 PTTM implants were placed in each jaw of 6 patients that met specific inclusion and exclusion criteria. Resonance Frequency Analysis (RFA) was conducted and Implant stability was recorded in ISQ values (Osstell ISQ, Osstell AB, Goteborg, Sweden) at implant placement and after 2,4,6,12 and 18 months of functional loading. Mean bone loss was also evaluated at the same interval of time on each periapical radiographs, bone levels were calculated by measuring the distance from the implant shoulder to the first bone to implant contact. RESULTS: Cumulative implant survival rate is 100% (n=25/25) to date and mean ISQ values recorded were: 72.14±5.61 (range= 50-81) at surgery, 64.39±8.12 (range=44-74) after 2 months, 74.26±7.14 (range=44-74) after 4 months, 76.84±7.65 (range=60-83) after 6 months, 78.13±4.14 (range=64-84) after 12 months and 80.22±6.23 (range=68-89) after 18 months of functional loading. Mean crestal marginal bone loss was 0.19±0.25 mm after 2 months of functional loading on periapical radiographs, 0.22±0.4 mm at 4 months, 0.3±0.46 mm at 6 months, 0.57±0.62 at 1 year and 0.64±0.60 mm after 18 months. CONCLUSIONS: The results of this study, even if limited by the number of implants placed indicate that PTTM dental implants have a clinical efficacy in prosthetic rehabilitation of post-oncological patients, due to trabecular structure of the porous Ta metal that increases bone-implant connection values.

19.
Clin Dev Immunol ; 2012: 483935, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22400036

RESUMO

To investigate the usefulness of serum cytokine dosage in the clinical management of cystic echinococcosis (CE), we analyzed serum levels of Th1 and Th2 cytokines in patients with hepatic CE in different cyst stages, CE1-2 (active), CE3a-3b (transitional), and CE4-5 (inactive). Ex vivo assessment of Th1 (IFN-γ) and Th2 (IL-4, IL-13, and IL-10) cytokines in sera was carried out using ELISA. IL-10 was undetectable in all serum samples of patients and controls, while a few sera contained measurable amounts of IFN-γ, IL-4, and IL-13. No statistically significant difference was found between the percentages of positive samples for each cytokine and the different groups analyzed (patients/controls, stage, number, location, and size of the cyst, serology, and sex of patients), with the exception of the association of IL-4 and IL-13 with the cyst stage. Overall, this investigation showed many limits of serum cytokine dosage as a marker of biological activity of echinococcal cysts. Because of low sensitivity and lack of specificity of this test, we believe that other ways to evaluate ex vivo biological activity of the cysts should be explored.


Assuntos
Citocinas/sangue , Equinococose Hepática/imunologia , Echinococcus/imunologia , Estágios do Ciclo de Vida/imunologia , Fígado/imunologia , Animais , Biomarcadores/sangue , Citocinas/imunologia , Equinococose Hepática/parasitologia , Equinococose Hepática/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Fígado/parasitologia , Fígado/patologia , Masculino , Carga Parasitária , Células Th1/citologia , Células Th1/imunologia , Células Th1/metabolismo , Equilíbrio Th1-Th2 , Células Th2/citologia , Células Th2/imunologia , Células Th2/metabolismo
20.
PLoS Negl Trop Dis ; 5(6): e1154, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21695106

RESUMO

Percutaneous treatment (PT) emerged in the mid-1980s as an alternative to surgery for selected cases of abdominal cystic echinococcosis (CE). Despite its efficacy and widespread use, the puncture of echinococcal cysts is still far from being universally accepted. One of the main reasons for this reluctance is the perceived risk of anaphylaxis linked to PTs. To quantify the risk of anaphylactic reactions and lethal anaphylaxis with PT, we systematically searched MEDLINE for publications on PT of CE and reviewed the PT-related complications. After including 124 publications published between 1980 and 2010, we collected a total number of 5943 PT procedures on 5517 hepatic and non-hepatic echinococcal cysts. Overall, two cases of lethal anaphylaxis and 99 reversible anaphylactic reactions were reported. Lethal anaphylaxis occurred in 0.03% of PT procedures, corresponding to 0.04% of treated cysts, while reversible allergic reactions complicated 1.7% of PTs, corresponding to 1.8% of treated echinococcal cysts. Analysis of the literature shows that lethal anaphylaxis related to percutaneous treatment of CE is an extremely rare event and is observed no more frequently than drug-related anaphylactic side effects.


Assuntos
Anafilaxia/induzido quimicamente , Anafilaxia/epidemiologia , Equinococose/terapia , Medição de Risco , Anafilaxia/psicologia , Equinococose/complicações , Humanos , Incidência
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