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Hsp90 (i.e., Heat shock protein 90) is a well-established therapeutic target for several diseases, ranging from misfolding-related disfunctions to cancer. In this framework, we have developed in recent years a family of benzofuran compounds that act as Hsp90 allosteric modulators. Such molecules can interfere with the stability of some relevant Hsp90 client oncoproteins, showing a low µM cytotoxic activity in vitro in cancer cell lines. Here we identify the target profile of these chemical probes by means of chemical proteomics, which established MDH2 (mitochondrial malate dehydrogenase) as an additional relevant cellular target that might help elucidate the molecular mechanism of their citotoxicity. Western blotting, DARTS (i.e., Drug Affinity Responsive Target Stability) and enzymatic assays data confirmed a dose-dependent interaction of MDH2 with several members of the benzofuran Hsp90 modulators family and a computational model allowed to interpret the observed interactions.
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Antineoplásicos/farmacologia , Benzofuranos/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Malato Desidrogenase/antagonistas & inibidores , Regulação Alostérica/efeitos dos fármacos , Antineoplásicos/química , Benzofuranos/química , Relação Dose-Resposta a Droga , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Malato Desidrogenase/metabolismo , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
Coronavirus disease 2019 (COVID-19) is a global public health emergency with many clinical facets, and new knowledge about its pathogenetic mechanisms is deemed necessary; among these, there are certainly coagulation disorders. In the history of medicine, autopsies and tissue sampling have played a fundamental role in order to understand the pathogenesis of emerging diseases, including infectious ones; compared to the past, histopathology can be now expanded by innovative techniques and modern technologies. For the first time in worldwide literature, we provide a detailed postmortem and biopsy report on the marked increase, up to 1 order of magnitude, of naked megakaryocyte nuclei in the bone marrow and lungs from serious COVID-19 patients. Most likely related to high interleukin-6 serum levels stimulating megakaryocytopoiesis, this phenomenon concurs to explain well the pulmonary abnormal immunothrombosis in these critically ill patients, all without molecular or electron microscopy signs of megakaryocyte infection.
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Betacoronavirus/patogenicidade , Medula Óssea/patologia , Infecções por Coronavirus/patologia , Síndrome da Liberação de Citocina/patologia , Coagulação Intravascular Disseminada/patologia , Pulmão/patologia , Pneumonia Viral/patologia , Trombose/patologia , Adulto , Idoso , Autopsia , Betacoronavirus/imunologia , Medula Óssea/imunologia , Medula Óssea/virologia , COVID-19 , Núcleo Celular/imunologia , Núcleo Celular/patologia , Núcleo Celular/virologia , Infecções por Coronavirus/complicações , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Estado Terminal , Síndrome da Liberação de Citocina/complicações , Síndrome da Liberação de Citocina/imunologia , Síndrome da Liberação de Citocina/virologia , Coagulação Intravascular Disseminada/complicações , Coagulação Intravascular Disseminada/imunologia , Coagulação Intravascular Disseminada/virologia , Evolução Fatal , Interações Hospedeiro-Patógeno/imunologia , Humanos , Interleucina-6/biossíntese , Interleucina-6/imunologia , Pulmão/imunologia , Pulmão/virologia , Masculino , Megacariócitos/imunologia , Megacariócitos/patologia , Megacariócitos/virologia , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , SARS-CoV-2 , Índice de Gravidade de Doença , Trombopoese/imunologia , Trombose/complicações , Trombose/imunologia , Trombose/virologiaRESUMO
In the last few years, substantial progress has been made in the treatment of ovarian cancer, with increased knowledge about the biology of the disease. Ovarian cancer is a neoplasm strongly linked to defects in DNA repair mechanisms, where deficiency in the homologous recombination (HR) system results in a better response of ovarian cancers to therapy, whether platinum-based chemotherapy, anthracyclines, or poly (ADP-ribose) polymerase (PARP) inhibitors. More recently, it has been demonstrated that different ovarian cancer histotypes may have different immunogenicity. Interestingly, defects in HR systems are associated more frequently with higher tumor infiltrating lymphocytes, providing a rationale for developing combination therapy with immune-modulating agents and PARP inhibitors. Again, locoregional therapies combining heat shock and chemotherapy delivery have been shown to induce an anticancer immune response in vitro. Thus, the potential for locoregional therapeutic approaches that may impact the immune system, perhaps in combination with immune-modulating agents or PARP inhibitors, needs to be further explored. With this premise, we reviewed the main biological and clinical data demonstrating a strict interplay between the immune system, DNA repair mechanisms, and intraperitoneal therapies in ovarian cancer, with a focus on potential future therapeutic implications.
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Reparo do DNA , Imunidade , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/terapia , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Terapia Combinada/métodos , Reparo do DNA/efeitos dos fármacos , Feminino , Humanos , Hipertermia Induzida/métodos , Imunidade/efeitos dos fármacos , Imunoterapia/métodos , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Inflamação/terapia , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Ovário/imunologia , Ovário/patologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Reparo de DNA por Recombinação/efeitos dos fármacosRESUMO
Asymmetric cyclopropane synthesis currently requires bespoke strategies, methods, substrates, and reagents, even when targeting similar compounds. This approach slows down discovery and limits available chemical space. Introduced herein is a practical and versatile diazocompound and its performance in the first unified asymmetric synthesis of functionalized cyclopropanes. The redox-active leaving group in this reagent enhances the reactivity and selectivity of geminal carbene transfer. This effect allowed the asymmetric cyclopropanation of various olefins, including unfunctionalized aliphatic alkenes, that enables the three-step total synthesis of (-)-dictyoptereneâ A. This unified synthetic approach delivers high enantioselectivities that are independent of the stereoelectronic properties of the functional groups transferred. Our results demonstrate that orthogonally differentiated diazocompounds are viable and advantageous equivalents of single-carbon chirons.
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The coding region of GSTP1 gene is preceded by a large CpG-rich region that is frequently affected by methylation. In many cancer types, GSTP1 is affected by hypermethylation and, as a consequence, it has a low expression. The aim of this review is to give an overview on GSTP1 methylation studies with a special focus on liquid biopsy, thus to summarize methods, results, sample types, different diseases, to have a complete information regarding this promising epigenetic biomarker. We used all the most valuable scientific search engines (PubMed, Medline, Scopus and Web of Science) searching the following keywords: GSTP1, methylation, cancer, urine, serum, plasma and blood. GSTP1 is a largely investigated tissue biomarker in several malignancies such as prostate, breast, lung and hepatocellular carcinoma with good performances especially for diagnostic purposes. As a liquid biopsy biomarker, it has been mainly investigated in prostate cancer (PCa) where it showed a high specificity but a low sensitivity; thus, it is recommended in combination with other biomarkers. Despite the large number of published papers and the promising results, GSTP1 has not yet entered the clinical practice even for PCa diagnosis. For this reason, further large and prospective studies are needed to validate this assay.
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Biomarcadores Tumorais/genética , Glutationa S-Transferase pi/genética , Neoplasias da Próstata/diagnóstico , Humanos , Biópsia Líquida , Masculino , Metilação , Neoplasias da Próstata/genéticaAssuntos
COVID-19/complicações , Herpes Simples/complicações , Herpesvirus Humano 1/isolamento & purificação , Necrose Hepática Massiva/complicações , Viremia/complicações , Aciclovir/uso terapêutico , Antivirais/uso terapêutico , COVID-19/patologia , COVID-19/terapia , Gerenciamento Clínico , Herpes Simples/patologia , Herpes Simples/terapia , Herpesvirus Humano 1/efeitos dos fármacos , Humanos , Unidades de Terapia Intensiva , Masculino , Necrose Hepática Massiva/patologia , Necrose Hepática Massiva/terapia , Pessoa de Meia-Idade , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/isolamento & purificação , Índice de Gravidade de Doença , Viremia/patologia , Viremia/terapiaRESUMO
BACKGROUND: Epigenetic silencing mediated by CpG island methylation is a common feature of many cancers. Characterizing aberrant DNA methylation changes associated with prostate carcinogenesis could potentially identify a tumour-specific methylation pattern, facilitating the early diagnosis of prostate cancer. The objective of the study was to assess the methylation status of 40 tumour suppressor genes in prostate cancer and healthy prostatic tissues. METHODS: We used methylation specific-multiplex ligation probe amplification (MS-MLPA) assay in two independent case series (training and validation set). The training set comprised samples of prostate cancer tissue (n = 40), healthy prostatic tissue adjacent to the tumor (n = 26), and healthy non prostatic tissue (n = 23), for a total of 89 DNA samples; the validation set was composed of 40 prostate cancer tissue samples and their adjacent healthy prostatic tissue, for a total of 80 DNA samples. Methylation specific-polymerase chain reaction (MSP) was used to confirm the results obtained in the validation set. RESULTS: We identified five highly methylated genes in prostate cancer: GSTP1, RARB, RASSF1, SCGB3A1, CCND2 (P < 0.0001), with an area under the ROC curve varying between 0.89 (95 % CI 0.82-0.97) and 0.95 (95 % CI 0.90-1.00). Diagnostic accuracy ranged from 80 % (95 % CI 70-88) to 90 % (95 % CI 81-96). Moreover, a concordance rate ranging from 83 % (95 % CI 72-90) to 89 % (95 % CI 80-95) was observed between MS-MLPA and MSP. CONCLUSIONS: Our preliminary results highlighted that hypermethylation of GSTP1, RARB, RASSF1, SCGB3A1 and CCND2 was highly tumour-specific in prostate cancer tissue.
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Biomarcadores Tumorais/genética , Metilação de DNA/genética , Reação em Cadeia da Polimerase/métodos , Neoplasias da Próstata/genética , Idoso , Estudos de Casos e Controles , Análise por Conglomerados , Genes Supressores de Tumor , Humanos , Masculino , Neoplasias da Próstata/diagnóstico , Curva ROC , Reprodutibilidade dos TestesRESUMO
Surgical removal of head-neck vascular neoplasms may have severe complications, although surgery remains a very important treatment modality. One of the most important aspects is to avoid the rupture of the tumor's capsule and to minimize functional complications, especially in the excision of benign tumors. The transoral robotic surgery allows removing lesions in challenging anatomical areas. Furthermore, the current robotic instrumentation does not allow a fine dissection of the structures and capsule rupture is a potential event. Here, the authors describe a minimally invasive technique using transoral robotic surgery for removal of vascular tumors in head-neck. Particular attention was given to the description of the diagnostic work up, the preoperative assessment and the surgical steps. No complications were encountered postoperatively. Transoral robotic surgery for vascular tumors appears to be a safe and feasible technique with minimal complications.
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Adenoma Pleomorfo/cirurgia , Endoscopia/instrumentação , Endoscopia/métodos , Linfangioma/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Neoplasias Parotídeas/cirurgia , Neoplasias Faríngeas/cirurgia , Procedimentos Cirúrgicos Robóticos/instrumentação , Procedimentos Cirúrgicos Robóticos/métodos , Adenoma Pleomorfo/diagnóstico , Adenoma Pleomorfo/patologia , Adolescente , Feminino , Hemostasia Cirúrgica/instrumentação , Hemostasia Cirúrgica/métodos , Humanos , Linfangioma/diagnóstico , Linfangioma/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias Parotídeas/diagnóstico , Neoplasias Parotídeas/patologia , Neoplasias Faríngeas/diagnóstico , Neoplasias Faríngeas/patologia , Tomografia Computadorizada por Raios XRESUMO
A 69-year-old North African male with established diagnosis of sarcoidosis underwent a stereotactic prostate biopsy with fusion technique. At the histological analysis, non-necrotizing micro-granulomas were highlighted in 2 samples, while the immunohistochemical staining resulted negative for CK903/p63/racemase. To the best of our knowledge, only 16 cases of prostatic sarcoidosis have been reported in literature. With this case report we describe an incidental diagnosis of prostatic involvement of sarcoidotic disease and briefly review and discuss the available literature on the topic.
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BACKGROUND: The delayed diagnosis of skin tumors is associated with a worsened prognosis. The impact of the interruption of clinical and surgical health services during the COVID-19 pandemic lockdowns has been documented among many pathologies. The impact of delayed diagnoses on patients with cutaneous squamous cell carcinomas (cSCCs) is poorly defined. OBJECTIVE: To compare patient and lesion characteristics and the surgical management of excised cSCCs prior to the pandemic shutdown of services (2018-2019) with the phase following the pandemic's second wave (2021-2022). METHODS: An observational, single-center, cross-sectional study of 416 surgically excised cSCCs over the course of two years was performed. Only patients with histologically confirmed cSCC were enrolled. Data collection included patient demographics and lesion characteristics, time to surgery, surgical approach, and histological data. RESULTS: More cSCC lesions were excised prior to the interruption of services (n = 312 vs. n = 186). Lesions were significantly larger (1.7 ± 1.2 vs. 2.1 ± 1.5 cm; p = 0.006) and more invasive (52% vs. 89%; p < 0.001), in the period 2021-2022. Surgical reconstructive techniques were significantly different (p = 0.001). Metastatic involvement was confirmed in three subjects (one in 2018-2019 and two in 2021-2022). There were no significant differences in the time to surgery or patient characteristics. Multivariable regression analysis identified a 4.7-times higher risk of tumor invasion (OR 4.69, 95%CI 2.55-8.16, p < 0.001), a two-times higher chance of dermo-epidermal grafts (OR 2.06, 95%CI 1.09-3.88, p = 0.025), and a 3.2-times higher risk of positive surgical margins (OR 3.21, 95%CI 1.44-7.17, p = 0.004). CONCLUSIONS: Diagnostic delays of cutaneous SCCs associated with reduced patient access to clinical and diagnostic services are associated with a 4.7-times increased risk of more severe invasion, a three-times increased risk of positive surgical margins, and a significant impact on surgical management, compared to the pre-pandemic period. Comparable patient cohort characteristics and time to surgery remained unchanged.
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BACKGROUND: The molecular pathways involved in the onset and progression of idiopathic pulmonary fibrosis (IPF) still need to be fully clarified as some are shared with lung cancer development. HOXB7, a member of the homeobox (Hox) gene family, has been found involved in various cancers. METHODS: Immunohistochemical (IHC) analysis was run on lung tissue samples from surgical lung biopsy (SLB) of 19 patients with IPF, retrospectively selected from the IPF database of the University Hospital of Modena. HOXB7 expression was analyzed and compared with that of five patients with no evidence of pulmonary fibrosis as controls. RESULTS: The semi-quantitative analysis of IHC showed that HOXB7 protein expression was higher in IPF patients compared to controls (difference between means = 6.2 ± 2.37, p = 0.0157). Further, HOXB7 expression was higher in IPF patients with a higher extent of fibrosis (50-75%)-measured with high-resolution computer tomography-compared to those with a lower extent (0-25%) (difference between means = 25.74 ± 6.72, p = 0.004). CONCLUSIONS: The expression of HOXB7 is higher in the lung of IPF patients compared to controls, and was represented in different cellular compartments within the lung niche. Further investigations are needed to clarify its role in the pathogenesis and progression of IPF.
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Gain-of-function mutations in STING cause STING-associated vasculopathy with onset in infancy (SAVI) characterized by early-onset systemic inflammation, skin vasculopathy, and interstitial lung disease. Here, we report and characterize a novel STING variant (F269S) identified in a SAVI patient. Single-cell transcriptomics of patient bone marrow revealed spontaneous activation of interferon (IFN) and inflammatory pathways across cell types and a striking prevalence of circulating naïve T cells was observed. Inducible STING F269S expression conferred enhanced signaling through ligand-independent translocation of the protein to the Golgi, protecting cells from viral infections but preventing their efficient immune priming. Additionally, endothelial cell activation was promoted and further exacerbated by cytokine secretion by SAVI immune cells, resulting in inflammation and endothelial damage. Our findings identify STING F269S mutation as a novel pathogenic variant causing SAVI, highlight the importance of the crosstalk between endothelial and immune cells in the context of lung disease, and contribute to a better understanding of how aberrant STING activation can cause pathology.
Assuntos
Células Endoteliais , Proteínas de Membrana , Humanos , Lactente , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Mutação com Ganho de Função , Complexo de Golgi/metabolismo , Interferons/metabolismo , Interferons/genética , Doenças Pulmonares Intersticiais/genética , Doenças Pulmonares Intersticiais/patologia , Doenças Pulmonares Intersticiais/imunologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutação , Transdução de Sinais , Doenças Vasculares/genética , Doenças Vasculares/patologia , Recém-Nascido , Pré-Escolar , FemininoRESUMO
In the molecular era, proper archival conditions within pathology laboratories are crucial, especially for formalin-fixed paraffin-embedded (FFPE) tissue specimens retrieved years after the original diagnosis. Indeed, improper preservation can impact the integrity of nucleic acids and protein antigens. This study evaluates the quality status of stored FFPE blocks using multilevel omics approaches. FFPE blocks from 45 Non-Small Cell Lung Carcinoma (NSCLC) cases were analyzed. The blocks were collected from six different pathology archives across Italy with distinct environmental characteristics. Nucleic acids' quantity and quality, as well as protein antigens, were assessed using various techniques, including MALDI-MSI. RNA was quantitatively higher, but more fragmented, compared to DNA. DNA quantity and quality were suitable for molecular analyses in 94.4% and 62.3% of samples, respectively. RNA quantity was adequate across all samples, but it was optimal only in 22.3% of cases. DNA quality started to deteriorate after 6-8 years, whereas RNA quality diminished only after 10 years of storage. These data might suggest a particular DNA susceptibility to FFPE blocks conservation. Immunohistochemical intensity decreased significantly after 6-8 years of storage, and MALDI-MSI analysis revealed that younger tissue blocks contained more unique proteomic signals than the older ones. This study emphasizes the importance of proper FFPE archiving conditions for molecular analyses. Governance should prioritize attention to pathology archives to ensure quality preservation and optimize predictive testing. By elucidating the nuances of FFPE block storage, this research paves the way for enhanced molecular diagnostics and therapeutic insights regarding oncology and beyond.
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The Kolbe reaction forms carbon-carbon bonds through electrochemical decarboxylative coupling. Despite more than a century of study, the reaction has seen limited applications owing to extremely poor chemoselectivity and reliance on precious metal electrodes. In this work, we present a simple solution to this long-standing challenge: Switching the potential waveform from classical direct current to rapid alternating polarity renders various functional groups compatible and enables the reaction on sustainable carbon-based electrodes (amorphous carbon). This breakthrough enabled access to valuable molecules that range from useful unnatural amino acids to promising polymer building blocks from readily available carboxylic acids, including biomass-derived acids. Preliminary mechanistic studies implicate the role of waveform in modulating the local pH around the electrodes and the crucial role of acetone as an unconventional reaction solvent for Kolbe reaction.
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Introduction: Idiopathic pulmonary fibrosis (IPF) severely affects the lung leading to aberrant deposition of extracellular matrix and parenchymal stiffness with progressive functional derangement. The limited availability of fresh tissues represents one of the major limitations to study the molecular profiling of IPF lung tissue. The primary aim of this study was to explore the proteomic profiling yield of archived formalin-fixed paraffin-embedded (FFPE) specimens of IPF lung tissues. Methods: We further determined the protein expression according to respiratory functional decline at the time of biopsy. The total proteins isolated from 11 FFPE samples of IPF patients compared to 3 FFPE samples from a non-fibrotic lung defined as controls, were subjected to label-free quantitative proteomic analysis by liquid chromatography-mass spectrometry (LC-MS/MS) and resulted in the detection of about 400 proteins. Results: After the pairwise comparison between controls and IPF, functional enrichment analysis identified differentially expressed proteins that were involved in extracellular matrix signaling pathways, focal adhesion and transforming growth factor ß (TGF-ß) signaling pathways strongly associated with IPF onset and progression. Five proteins were significantly over- expressed in the lung of IPF patients with either advanced disease stage (Stage II) or impaired pulmonary function (FVC<75, DLCO<55) compared to controls; these were lymphocyte cytosolic protein 1 (LCP1), peroxiredoxin-2 (PRDX2), transgelin 2 (TAGLN2), lumican (LUM) and mimecan (OGN) that might play a key role in the fibrogenic processes. Discussion: Our work showed that the analysis of FFPE samples was able to identify key proteins that might be crucial for the IPF pathogenesis. These proteins are correlated with lung carcinogenesis or involved in the immune landscape of lung cancer, thus making possible common mechanisms between lung carcinogenesis and fibrosis progression, two pathological conditions at risk for each other in the real life.
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AIMS: To analyse the expression of several mucins (MUC1, MUC2, MUC3, MUC5AC and MUC6), epidermal growth factor receptor (EGFR), v-erb-b2 erythroblastic leukaemia viral oncogene homologue 2 (HER2), thyroid transcription factor-1 (TTF-1), caudal type homeobox 2 (CDX2) and cytokeratin 20 (CK20), and the presence of mutations of EGFR, KRAS and HER2 in congenital pulmonary airway malformations (CPAM). METHODS AND RESULTS: Forty-one cases of CPAM and six pulmonary sequestrations were included. TTF-1 expression was observed in all cases but was not seen in mucinogenic growths in CPAM. CDX2 expression was completely negative. MUC1 expression was noted in 12 (29%) CPAM and in 33% sequestrations. MUC5AC was noted in only five cases (26%) by immunohistochemistry and was found in the mucinogenic proliferations of type 1 CPAM. No immunolabelling was noted for the other mucins. EGFR was expressed variably in almost all cases, while HER2 and CK20 was seen exclusively in the mucinogenic proliferations. All mucinous growths were characterized by KRAS mutations. No EGFR and HER2 gene alterations were identified. CONCLUSIONS: KRAS mutations and MUC5AC, CK20 and HER2 expression was seen in all mucinogenic proliferations, supporting the neoplastic nature of these cytologically bland growths. These findings emphasize the importance of complete surgical resection of such lesions.
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Genes ras , Queratina-20/metabolismo , Pulmão/anormalidades , Pulmão/metabolismo , Mucina-5AC/metabolismo , Receptor ErbB-2/metabolismo , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/metabolismo , Adenocarcinoma Mucinoso/patologia , Adolescente , Adulto , Sequência de Bases , Sequestro Broncopulmonar/genética , Sequestro Broncopulmonar/metabolismo , Sequestro Broncopulmonar/patologia , Criança , Pré-Escolar , Primers do DNA/genética , Feminino , Feto/anormalidades , Feto/metabolismo , Feto/patologia , Humanos , Imuno-Histoquímica , Lactente , Recém-Nascido , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Proteínas Nucleares/metabolismo , Fator Nuclear 1 de Tireoide , Fatores de Transcrição/metabolismo , Adulto JovemRESUMO
Chiral cis-cyclopropanes are strained rigid analogues of alkyl chains, whose study and application are limited by their difficult synthesis. A modular approach from olefin materials is enabled by the discovery of the electron donor-acceptor (EDA) interaction between 2-substituted benzothiazolines and N-hydroxyphthalimide esters. These complexes are activated by visible light without photocatalysts, and the benzothiazoline reagent plays a triple role as a photoreductant, a stereoselective hydrogen-atom donor, and a Brønsted acid. Beyond the enantioselective synthesis of cis-cyclopropanes, these results introduce benzothiazolines as accessible and easily tunable self-sensitized photoreductants.
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Bladder cancer has a very high frequency of recurrence and therefore requires close clinical surveillance throughout its life, with cystoscopies and serial cytological examinations. These tests are both invasive and expensive, with considerable interpersonal and inter-institutional variability. Moreover, cytological examination used for the diagnosis of low-grade tumors has a low sensitivity; thus, there is an increasing focus on the research for new, accurate, urinary markers. Herein, the biological basis, methodologies, and diagnostic performance of biomarkers are discussed.
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Neoplasias da Bexiga Urinária/urina , Antígenos de Neoplasias/urina , Biomarcadores Tumorais/urina , Humanos , Imuno-Histoquímica/métodos , Hibridização in Situ Fluorescente/métodos , Proteínas Nucleares/urina , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Neoplasias da Bexiga Urinária/diagnósticoRESUMO
A combined experimental-computational approach has been used to study the cyclopropanation reaction of N-hydroxyphthalimide diazoacetate (NHPI-DA) with various olefins, catalyzed by a ruthenium-phenyloxazoline (Ru-Pheox) complex. Kinetic studies show that the better selectivity of the employed redox-active NHPI diazoacetate is a result of a much slower dimerization reaction compared to aliphatic diazoacetates. Density functional theory calculations reveal that several reactions can take place with similar energy barriers, namely, dimerization of the NHPI diazoacetate, cyclopropanation (inner-sphere and outer-sphere), and a previously unrecognized migratory insertion of the carbene into the phenyloxazoline ligand. The calculations show that the migratory insertion reaction yields an unconsidered ruthenium complex that is catalytically competent for both the dimerization and cyclopropanation, and its relevance is assessed experimentally. The stereoselectivity of the reaction is argued to stem from an intricate balance between the various mechanistic scenarios.
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INTRODUCTION AND IMPORTANCE: Mediastinal paragangliomas are rare neuroendocrine tumors that originate from extra-adrenal paraganglia, occasionally secreting catecholamines. Nonfunctional mediastinal paragangliomas present nonspecific clinical and radiological features and represent a diagnostic challenge. CASE PRESENTATION: A 53-year old woman presented with cough and dyspnea increasing over time. CT-scan and ultrasonography showed a large vascularized cervico-mediastinal mass, consistent with an intrathoracic ectopic goiter. Preoperative angiography showed a blood supply from neck vessels. The lesion was completely removed through a cervical approach. The diagnosis of paraganglioma was a histological surprise. The patient is alive without recurrence 30 months after surgery. CLINICAL DISCUSSION: When preoperatively diagnosed, the treatment of choice of a mediastinal paraganglioma is surgical excision. However, a preoperative diagnosis of mediastinal paraganglioma is difficult to obtain, especially in cases of nonfunctional lesions. Distinction between an intrathoracic goiter and a nonfunctional paraganglioma can be extremely difficult and, given the rarity of the latter, an ectopic goiter is suspected in first instance. CT-scan and ultrasonography are of little use in the differential diagnosis. However, scintigraphy with 123I-metaiodobenzylguanidine can be an useful diagnostic tool when a paraganglioma is suspected. In case of vascularized cervico-mediastinal mass, such as paragangliomas or intrathoracic goiter, preoperative angiography should be performed to study the blood supply and orient the surgical approach. CONCLUSION: Although uncommon, paragangliomas should be considered in the differential diagnosis of mediastinal masses, especially when an ectopic goiter is suspected.