RESUMO
Real-world data have revealed that a substantial portion of patients with myelodysplastic syndromes (MDS) does not respond to epigenetic therapy with hypomethylating agents (HMAs). The cellular and molecular reasons for this resistance to the demethylating agent and biomarkers that would be able to predict the treatment refractoriness are largely unknown. In this study, we shed light on this enigma by characterizing the epigenomic profiles of patients with MDS treated with azacitidine. Our approach provides a comprehensive view of the evolving DNA methylation architecture of the disease and holds great potential for advancing our understanding of MDS treatment responses to HMAs.
Assuntos
Azacitidina , Metilação de DNA , Síndromes Mielodisplásicas , Humanos , Azacitidina/uso terapêutico , Azacitidina/farmacologia , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Estudos Retrospectivos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Antimetabólitos Antineoplásicos/uso terapêutico , Antimetabólitos Antineoplásicos/farmacologia , Idoso de 80 Anos ou mais , Epigênese Genética/efeitos dos fármacos , Resultado do TratamentoRESUMO
In this Letter, we theoretically study spontaneous parametric downconversion (SPDC) in a periodically poled structure composed of two linearly uncoupled resonators that are nonlinearly coupled via a Mach-Zehnder interferometer. The device does not require dispersion engineering to achieve efficient doubly resonant SPDC, and, unlike the case of a single resonator, one can reconfigure the system to generate photon pairs over a bandwidth of hundreds of nm. We consider the case of SPDC pumped at 775 nm in a periodically poled lithium niobate (PPLN) device compatible with up-to-date technological platforms. We calculated pair generation rates of up to 250 MHz/mW pump power for a single resonance and integrated pair generation rates of up to 100 THz/mW pump power over 170 nm. When properly reconfigured, a single device can efficiently generate over a bandwidth of some 300 nm, covering the S, C, L, and U infrared bands.
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Appropriate regeneration of jawbone after dental or surgical procedures relies on the recruitment of osteoprogenitor cells able to differentiate into matrix-producing osteoblasts. In this context, photobiomodulation (PBM) has emerged as promising therapy to improve tissue regeneration and to facilitate wound healing processes. The aim of this study was to determine the effect of PBM on human osteoprogenitor cells isolated from mandibular trabecular bone.Bone marrow stromal cell cultures were established from 4 donors and induced toward osteogenic differentiation for 14 days in a standard osteogenic assay. Cells were irradiated with a combined red/near-infrared (NIR) laser following different schedules and expression of osteogenic, matrix-related, osteoclastogenic and inflammatory genes was analyzed by quantitative PCR.Gene expression analysis revealed no overall effects of PBM on osteogenic differentiation. However, a statistically significant reduction was observed in the transcripts of COL1A1 and MMP13, two important genes involved in the bone matrix homeostasis. Most important, PBM significantly downregulated the expression of RANKL, IL6 and IL1B, three genes that are involved in both osteoclastogenesis and inflammation.In conclusion, PBM with a red/NIR laser did not modulate the osteogenic phenotype of mandibular osteoprogenitors but markedly reduced their expression of matrix-related genes and their pro-osteoclastogenic and pro-inflammatory profile.
Assuntos
Diferenciação Celular , Terapia com Luz de Baixa Intensidade , Mandíbula , Osteogênese , Humanos , Terapia com Luz de Baixa Intensidade/métodos , Osteogênese/efeitos da radiação , Mandíbula/efeitos da radiação , Diferenciação Celular/efeitos da radiação , Interleucina-1beta/metabolismo , Interleucina-1beta/genética , Ligante RANK/metabolismo , Ligante RANK/genética , Células-Tronco Mesenquimais/efeitos da radiação , Células-Tronco Mesenquimais/metabolismo , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 13 da Matriz/genética , Interleucina-6/metabolismo , Interleucina-6/genética , Osteoclastos/efeitos da radiação , Células Cultivadas , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Cadeia alfa 1 do Colágeno Tipo I , Expressão Gênica/efeitos da radiação , Inflamação/radioterapia , Raios Infravermelhos/uso terapêuticoRESUMO
Erythropoiesis regulation is essential in normal physiology and pathology, particularly in myelodysplastic syndromes (MDS) and ß-thalassemia. Several signaling transduction processes, including those regulated by inositides, are implicated in erythropoiesis, and the latest MDS or ß-thalassemia preclinical and clinical studies are now based on their regulation. Among others, the main pathways involved are those regulated by transforming growth factor (TGF)-ß, which negatively regulates erythrocyte differentiation and maturation, and erythropoietin (EPO), which acts on the early-stage erythropoiesis. Also small mother against decapentaplegic (SMAD) signaling molecules play a role in pathology, and activin receptor ligand traps are being investigated for future clinical applications. Even inositide-dependent signaling, which is important in the regulation of cell proliferation and differentiation, is specifically associated with erythropoiesis, with phospholipase C (PLC) and phosphatidylinositol 3-kinase (PI3K) as key players that are becoming increasingly important as new promising therapeutic targets. Additionally, Roxadustat, a new erythropoiesis stimulating agent targeting hypoxia inducible factor (HIF), is under clinical development. Here, we review the role and function of the above-mentioned signaling pathways, and we describe the state of the art and new perspectives of erythropoiesis regulation in MDS and ß-thalassemia.
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Eritropoese , Síndromes Mielodisplásicas/metabolismo , Transdução de Sinais , Talassemia beta/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Ensaios Clínicos como Assunto , Eritropoetina/metabolismo , Glicina/análogos & derivados , Glicina/farmacologia , Hematínicos/uso terapêutico , Humanos , Fator 1 Induzível por Hipóxia/metabolismo , Isoquinolinas/farmacologia , Ligantes , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fosfolipases Tipo C/metabolismoAssuntos
Interleucina-7 , Janus Quinases , Fosfatidilinositol 3-Quinases , Leucemia-Linfoma Linfoblástico de Células Precursoras , Proteínas Proto-Oncogênicas c-akt , Fator de Transcrição STAT5 , Transdução de Sinais , Serina-Treonina Quinases TOR , Adulto , Criança , Humanos , Interleucina-7/metabolismo , Janus Quinases/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição STAT5/metabolismo , Serina-Treonina Quinases TOR/metabolismoRESUMO
A highly sensitive electrochemical immunoassay for the initial diagnosis of celiac disease (CD) in saliva samples that overcomes the problems related to its high viscosity and to the low concentration of anti-transglutaminase antigen (tTG) IgA in this medium has been developed for the first time. The system uses magnetic beads (MBs) covered with tTG, which reacts with the anti-tTG IgA antibodies present in positive saliva samples. An anti-human IgA, conjugated with alkaline phosphate (AP) enzyme, was used as the label and a strip of eight magnetized screen-printed electrodes as the electrochemical transducer. In particular, two different immunoassay approaches were optimized and blindly compared to analyze a large number of saliva samples, whose anti-tTG IgA levels were independently determined by the radioimmunoassay (RIA) method. The obtained results, expressed as Ab index, were used to perform a diagnostic test evaluation through the construction of receiver operating characteristic (ROC) curves. The approach, involving a pre-incubation between the anti-human IgA-AP and saliva samples prior to the addition of MBs-tTG, showed a cutoff of 0.022 with 95% clinical sensitivity and 96% clinical specificity. The area under the ROC curve is equal to 1, a result that classifies our test as "perfect." This study demonstrates that it is possible to perform the screening of CD with a rapid, simple, inexpensive, and sensitive method able to detect anti-tTG antibodies in saliva samples, which are easily obtained by non-invasive techniques. This aspect is of fundamental importance to screen a large number of subjects, especially in the pediatric age.
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Doença Celíaca/diagnóstico , Doença Celíaca/metabolismo , Condutometria/instrumentação , Imunoensaio/instrumentação , Programas de Rastreamento/instrumentação , Saliva/metabolismo , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Brain derived neurotrophic factor (BDNF) is a neurotrophin, expressed in the central nervous system and in peripheral tissues, that is regulated by the Gsα/cAMP pathway. In bone, it regulates osteogenesis and stimulates RANKL secretion and osteoclast formation in osteolytic tumors such as Multiple Myeloma. Fibrous dysplasia (FD) of bone is a rare genetic disease of the skeleton caused by gain-of-function mutations of the Gsα gene in which RANKL-dependent enhanced bone resorption is a major cause of bone fragility and clinical morbidity. We observed that BDNF transcripts are expressed in human FD lesions. Specifically, immunolocalization studies performed on biopsies obtained from FD patients revealed the expression of BDNF in osteoblasts and, to a lower extent, in the spindle-shaped cells within the fibrous tissue. Therefore, we hypothesized that BDNF can play a role in the pathogenesis of FD by stimulating RANKL secretion and bone resorption. To test this hypothesis, we used the EF1α-GsαR201C mouse model of the human disease (FD mice). Western blot analysis revealed a higher expression of BDNF in bone segments of FD mice compared to WT mice and the immunolabeling pattern within mouse FD lesions was similar to that observed in human FD. Treatment of FD mice with a monoclonal antibody against BDNF reduced the fibrous tissue along with the number of osteoclasts and osteoblasts within femoral lesions. These results reveal BDNF as a new player in the pathogenesis of FD and a potential molecular mechanism by which osteoclastogenesis may be nourished within FD bone lesions. They also suggest that BDNF inhibition may be a new approach to reduce abnormal bone remodeling in FD.
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Reabsorção Óssea , Displasia Fibrosa Óssea , Humanos , Camundongos , Animais , Fator Neurotrófico Derivado do Encéfalo , Osso e Ossos/metabolismo , Displasia Fibrosa Óssea/genética , Osteoclastos/metabolismoRESUMO
The hierarchical organization of the leukemic stem cells (LSCs) is identical to that of healthy counterpart cells. It may be split into roughly three stages: a small number of pluripotent stem cells at the top, few lineage-restricted cells in the middle, and several terminally differentiated blood cells at the bottom. Although LSCs can differentiate into the hematopoietic lineage, they can also accumulate as immature progenitor cells, also known as blast cells. Since blast cells are uncommon in healthy bloodstreams, their presence might be a sign of cancer. For instance, a 20% blast cutoff in peripheral blood or bone marrow is formally used to distinguish acute myeloid leukemia from myelodysplastic neoplasms, which is essential to plan the patients' management. Many techniques may be useful for blast enumeration: one of them is flow cytometry, which can perform analyses on many cells by detecting the expression of cell surface markers. Leukemic and non-leukemic blast cells might indeed be characterized by the same surface markers, but these markers are usually differently expressed. Here we propose to use CD45, in combination with CD34 and other cell surface markers, to identify and immunophenotype blast cells in patient-derived samples.
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Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/genética , Medula Óssea/metabolismo , Antígenos CD34/metabolismo , Citometria de Fluxo/métodos , Células-Tronco Neoplásicas/metabolismo , ImunofenotipagemRESUMO
Myelodysplastic Syndromes, a heterogeneous group of hematological disorders, are characterized by abnormalities in phosphoinositide-dependent signaling, epigenetic regulators, apoptosis, and cytokine interactions within the bone marrow microenvironment, contributing to disease pathogenesis and neoplastic growth. Comprehensive knowledge of these pathways is crucial for the development of innovative therapies that aim to restore normal apoptosis and improve patient outcomes.
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Células-Tronco Hematopoéticas , Síndromes Mielodisplásicas , Humanos , Células-Tronco Hematopoéticas/metabolismo , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Medula Óssea/patologia , Citocinas/metabolismo , Transdução de SinaisRESUMO
Cadaver dissection has always played a fundamental role in medical education. However, especially in Italy, the topic of body donation has remained partially unknown for years. The current study analyses graphic medicine as a new possible communication tool, evaluating and reflecting, with second-year students enrolled in the International School of Medicine and Surgery at the University of Bologna, about its potentialities for body donation awareness-raising in both the scientific community and the general population. For the first time in an Italian University, two graphic medicine workshops were organized focusing on human anatomy and body donation. Seminars were positively evaluated by students using a four items Likert-scale question: mean 3.54 (± SD 0.73) for the Likert question about the experiences of the workshops; 3.88 (± 0.33) for the Likert question regarding the use of graphic medicine in body donation awareness campaigns among the general population; 3.59 (± 0.65) for the Likert question regarding the use of graphic medicine in body donation awareness campaigns among the scientific community. Furthermore, the open-ended questions included in the anonymous questionnaire were analyzed using the constructivist grounded qualitative analysis, whence various themes emerged. Finally, five graphic medicine projects about body donation were created by students, proving their interest in testing this method to promote body donation, focusing the attention on different communicative aspects. Considering the results of this pilot study, the co-creative collaborative use of graphic medicine could be evaluated as an additional strategy to increase body donation awareness-raising in Italy and beyond, especially in the non-experts' community.
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Anatomia , Estudantes de Medicina , Humanos , Projetos Piloto , Anatomia/educação , Dissecação/educação , Corpo Humano , Inquéritos e Questionários , CadáverRESUMO
Aberrant signaling pathways regulating proliferation and differentiation of hematopoietic stem cells (HSCs) can contribute to disease pathogenesis and neoplastic growth. Phosphoinositides (PIs) are inositol phospholipids that are implicated in the regulation of critical signaling pathways: aberrant regulation of Phospholipase C (PLC) beta1, PLCgamma1 and the PI3K/Akt/mTOR pathway play essential roles in the pathogenesis of Myelodysplastic Syndromes (MDS) and Acute Myeloid Leukemia (AML).
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Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/fisiologia , Leucemia Mieloide Aguda/metabolismo , Fosfatidilinositóis/metabolismo , Síndromes Mielodisplásicas/metabolismoRESUMO
BACKGROUND: miRNAs are small non-coding RNAs that regulate gene expression and are linked to cancer development and progression. miRNA profiles are currently studied as new prognostic factors or therapeutic perspectives. Among hematological cancers, myelodysplastic syndromes at higher risk of evolution into acute myeloid leukemia are treated with hypomethylating agents, like azacitidine, alone or in combination with other drugs, such as lenalidomide. Recent data showed that, during azacitidine and lenalidomide therapy, the concurrent acquisition of specific point mutations affecting inositide signalling pathways is associated with lack or loss of response to therapy. As these molecules are implicated in epigenetic processes, possibly involving miRNA regulation, and in leukemic progression, through the regulation of proliferation, differentiation and apoptosis, here we performed a new miRNA expression analysis of 26 high-risk patients with myelodysplastic syndromes treated with azacitidine and lenalidomide at baseline and during therapy. miRNA array data were processed, and bioinformatic results were correlated with clinical outcome to investigate the translational relevance of selected miRNAs, while the relationship between selected miRNAs and specific molecules was experimentally tested and proven. RESULTS: Patients' overall response rate was 76.9% (20/26 cases): complete remission (5/26, 19.2%), partial remission (1/26, 3.8%), marrow complete remission (2/26, 7.7%), hematologic improvement (6/26, 23.1%), hematologic improvement with marrow complete remission (6/26, 23.1%), whereas 6/26 patients (23.1%) had a stable disease. miRNA paired analysis showed a statistically significant up-regulation of miR-192-5p after 4 cycles of therapy (vs baseline), that was confirmed by real-time PCR analyses, along with an involvement of BCL2, that was proven to be a miR-192-5p target in hematopoietic cells by luciferase assays. Furthermore, Kaplan-Meier analyses showed a significant correlation between high levels of miR-192-5p after 4 cycles of therapy and overall survival or leukemia-free survival, that was stronger in responders, as compared with patients early losing response and non-responders. CONCLUSIONS: This study shows that high levels of miR-192-5p are associated with higher overall survival and leukemia-free survival in myelodysplastic syndromes responding to azacitidine and lenalidomide. Moreover, miR-192-5p specifically targets and inhibits BCL2, possibly regulating proliferation and apoptosis and leading to the identification of new therapeutic targets.
Assuntos
Leucemia Mieloide Aguda , MicroRNAs , Síndromes Mielodisplásicas , Humanos , Azacitidina/farmacologia , Azacitidina/uso terapêutico , Lenalidomida/farmacologia , Lenalidomida/uso terapêutico , MicroRNAs/genética , Metilação de DNA , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Leucemia Mieloide Aguda/genética , Proteínas Proto-Oncogênicas c-bcl-2RESUMO
Coeliac disease (CD) is a gluten-induced autoimmune enteropathy found in genetically susceptible subjects. Because of the high number of undetected cases, rapid and cheaper screening methods are needed. Currently, the CD diagnosis involves the detection of anti-transglutaminase IgA antibodies (anti-tTG IgA) in blood serum through the use of ELISA systems with confirmation by histology of the intestinal mucosa. A new, rapid magneto-electrochemical immunosensor for CD diagnosis has been developed and applied to serum sample analysis. The system uses magnetic beads coated with tTG antigen to detect anti-tTG antibodies in positive serum samples and an alkaline phosphatase-conjugated anti-human IgA as label. An electrochemical readout, using magnetized screen-printed electrodes coupled with a portable instrument, is made after the addition of α-naphtyl phosphate, which is enzymatically converted into the electrochemically active α-naphthol product. The work involved the following considerations: (1) optimization of analytical parameters; (2) recovery evaluation, adding known concentrations of anti-tTG IgA to "blank" sera; (3) analysis of 107 blood serum samples; (4) calculation of the ROC curve, resulting in a cut-off of 1.0 U/ml, 100% of clinical sensitivity and 98.36% of clinical specificity; evaluation of the agreement between electrochemical and ELISA kit values (r (2) of 0.943). The system developed could be an useful tool for a correct and rapid CD diagnosis. This method is simple, cheap, rapid, and suitable for screening analyses performed outside of the classical diagnostic laboratory.
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Doença Celíaca/diagnóstico , Técnicas Eletroquímicas/métodos , Imunoensaio/métodos , Doença Celíaca/enzimologia , Doença Celíaca/imunologia , Humanos , Imunoglobulina A/análise , Imunoglobulina A/imunologia , Magnetismo , Transglutaminases/imunologiaRESUMO
Although hemangiomas, benign tumors of vascular origin, are very common among children and represent the most frequent benign tumor at that age, their association with other malformations constitutes a rare neurocutaneous disorder called PHACE syndrome. This condition is characterized by posterior fossa anomalies, hemangioma of the face, arterial alterations, cardiac defects, and eye anomalies (as represented by the acronym PHACE); sternum defects, endocrinopathies, and thyreopathies may be present as well. In this report, we describe a case of congenital hypothyroidism due to an empty thyroid site, as demonstrated by ultrasound, in an Italian child.
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Coartação Aórtica/complicações , Hipotireoidismo Congênito/complicações , Hipotireoidismo Congênito/diagnóstico por imagem , Anormalidades do Olho/complicações , Síndromes Neurocutâneas/complicações , Disgenesia da Tireoide/complicações , Disgenesia da Tireoide/diagnóstico por imagem , Feminino , Humanos , Recém-Nascido , UltrassonografiaRESUMO
Gross anatomy knowledge is an essential element for medical students in their education, and nowadays, cadaver-based instruction represents the main instructional tool able to provide three-dimensional (3D) and topographical comprehensions. The aim of the study was to develop and test a prototype of an innovative tool for medical education in human anatomy based on the combination of augmented reality (AR) technology and a tangible 3D printed model that can be explored and manipulated by trainees, thus favoring a three-dimensional and topographical learning approach. After development of the tool, called AEducaAR (Anatomical Education with Augmented Reality), it was tested and evaluated by 62 second-year degree medical students attending the human anatomy course at the International School of Medicine and Surgery of the University of Bologna. Students were divided into two groups: AEducaAR-based learning ("AEducaAR group") was compared to standard learning using human anatomy atlas ("Control group"). Both groups performed an objective test and an anonymous questionnaire. In the objective test, the results showed no significant difference between the two learning methods; instead, in the questionnaire, students showed enthusiasm and interest for the new tool and highlighted its training potentiality in open-ended comments. Therefore, the presented AEducaAR tool, once implemented, may contribute to enhancing students' motivation for learning, increasing long-term memory retention and 3D comprehension of anatomical structures. Moreover, this new tool might help medical students to approach to innovative medical devices and technologies useful in their future careers.
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Realidade Aumentada , Estudantes de Medicina , Cadáver , Avaliação Educacional , Humanos , Impressão TridimensionalRESUMO
Polyphosphoinositides (PPIns) and their modulating enzymes are involved in regulating many important cellular functions including proliferation, differentiation or gene expression, and their deregulation is involved in human diseases such as metabolic syndromes, neurodegenerative disorders and cancer, including Acute Myeloid Leukemia (AML). Given that PPIns regulating enzymes are highly druggable targets, several studies have recently highlighted the potential of targeting them in AML. For instance many inhibitors targeting the PI3K pathway are in various stages of clinical development and more recently other novel enzymes such as PIP4K2A have been implicated as AML targets. PPIns have distinct subcellular organelle profiles, in part driven by the specific localisation of enzymes that metabolise them. In particular, in the nucleus, PPIns are regulated in response to various extracellular and intracellular pathways and interact with specific nuclear proteins to control epigenetic cell state. While AML does not normally manifest with as many mutations as other cancers, it does appear in large part to be a disease of dysregulation of epigenetic signalling and many novel therapeutics are aimed at reprogramming AML cells toward a differentiated cell state or to one that is responsive to alternative successful but limited AML therapies such as ATRA. Here, we propose that by combining bioinformatic analysis with inhibition of PPIns pathways, especially within the nucleus, we might discover new combination therapies aimed at reprogramming transcriptional output to attenuate uncontrolled AML cell growth. Furthermore, we outline how different part of a PPIns signalling unit might be targeted to control selective outputs that might engender more specific and therefore less toxic inhibitory outcomes.
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Myelodysplastic syndromes (MDS) are a heterogeneous group of hematological malignancies characterized by peripheral blood cytopenia and abnormal myeloproliferation, as well as a variable risk of evolution into acute myeloid leukemia (AML). The nucleus is a highly organized organelle with several distinct domains where nuclear inositides localize to mediate essential cellular events. Nuclear inositides play a critical role in the modulation of erythropoiesis or myelopoiesis. Here, we briefly review the nuclear structure, the localization of inositides and their metabolic enzymes in subnuclear compartments, and the molecular aspects of nuclear inositides in MDS.