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1.
Endocr Pract ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38815693

RESUMO

OBJECTIVE: The European Thyroid Imaging Reporting and Data System (EU-TIRADS) allows for selective fine needle aspiration cytology (FNAC). In 2017, EU-TIRADS was implemented as part of a nationwide standardized care bundle for thyroid cancer in Western Sweden with a population of approximately 1.7 million. The objective of this study was to investigate the clinical value of EU-TIRADS attempting to reduce the number of unnecessary FNACs in referred patients with thyroid nodules. METHODS: The study cohort consisted of all patients referred to Sahlgrenska University Hospital due to a palpable, newly detected or growing thyroid nodules or a positron emission tomography-positive finding for examination with thyroid ultrasound and selective cytology between 2018 and 2022. Medical records on EU-TIRADS classification, corresponding FNAC results, and histopathologic diagnosis were retrospectively collected. Adherence to the EU-TIRADS guidelines, use of selective FNAC, and rate of malignancy in patients who underwent surgery were assessed. RESULTS: In total, 1246 thyroid nodules in 990 patients were evaluated. The distributions of EU-TIRADS 2 to 5 (number [percentage]) for all examined nodules were 63 (5%), 462 (37%), 443 (36%), and 278 (22%), respectively. FNAC was omitted in 7% of the investigated patients. FNAC was performed in 124 nodules (10%) despite not fulfilling the EU-TIRADS criteria or absence of positron emission tomography-positive findings. The rate of malignancy was 33% and 1/50 in patients who underwent "unnecessary" FNAC. CONCLUSION: Implementation of EU-TIRADS in routine management of thyroid nodules led to the selective use of FNAC; however, the clinical impact was limited. This study provides real-world data on the value and magnitude of diagnostic improvement by implementing EU-TIRADS in clinical practice.

2.
Development ; 145(2)2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-29361553

RESUMO

The developmental program that regulates thyroid progenitor cell proliferation is largely unknown. Here, we show that branching-like morphogenesis is a driving force to attain final size of the embryonic thyroid gland in mice. Sox9, a key factor in branching organ development, distinguishes Nkx2-1+ cells in the thyroid bud from the progenitors that originally form the thyroid placode in anterior endoderm. As lobes develop the thyroid primordial tissue branches several generations. Sox9 and Fgfr2b are co-expressed distally in the branching epithelium prior to folliculogenesis. The thyroid in Fgf10 null mutants has a normal shape but is severely hypoplastic. Absence of Fgf10 leads to defective branching and disorganized angiofollicular units although Sox9/Fgfr2b expression and the ability of cells to differentiate and form nascent follicles are not impaired. These findings demonstrate a novel mechanism of thyroid development reminiscent of the Fgf10-Sox9 program that characterizes organogenesis in classical branching organs, and provide clues to aid understanding of how the endocrine thyroid gland once evolved from an exocrine ancestor present in the invertebrate endostyle.


Assuntos
Embrião de Mamíferos/embriologia , Glândula Tireoide/embriologia , Animais , Embrião de Mamíferos/citologia , Fator 10 de Crescimento de Fibroblastos/genética , Fator 10 de Crescimento de Fibroblastos/metabolismo , Camundongos , Camundongos Knockout , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Glândula Tireoide/citologia
3.
Development ; 144(12): 2123-2140, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28634271

RESUMO

Thyroid hormones are crucial for organismal development and homeostasis. In humans, untreated congenital hypothyroidism due to thyroid agenesis inevitably leads to cretinism, which comprises irreversible brain dysfunction and dwarfism. Elucidating how the thyroid gland - the only source of thyroid hormones in the body - develops is thus key for understanding and treating thyroid dysgenesis, and for generating thyroid cells in vitro that might be used for cell-based therapies. Here, we review the principal mechanisms involved in thyroid organogenesis and functional differentiation, highlighting how the thyroid forerunner evolved from the endostyle in protochordates to the endocrine gland found in vertebrates. New findings on the specification and fate decisions of thyroid progenitors, and the morphogenesis of precursor cells into hormone-producing follicular units, are also discussed.


Assuntos
Glândula Tireoide/embriologia , Animais , Evolução Biológica , Diferenciação Celular , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Organogênese/genética , Organogênese/fisiologia , Transdução de Sinais , Glândula Tireoide/crescimento & desenvolvimento , Glândula Tireoide/fisiologia , Hormônios Tireóideos/genética , Hormônios Tireóideos/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia
4.
Inorg Chem ; 58(6): 3559-3563, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30807118

RESUMO

Separation of U, Np, and Pu from used nuclear fuel (UNF) would result in lower long-term radiotoxicity, alleviating constraints on the storage and handling of the material. The complexity of UNF requires several industrial-scale processes with multiple waste streams. A one-step solution to the group removal of the elements, U-Pu, is desirable. Here we present a possible solution to group actinide separation utilizing the unique dioxy conformation of An(V/VI) cations and demonstrate the ability of a tetradentate lipophilic Schiff base ligand (L) to yield isostructural complexes of the general formula [(AnVIO2)(L)(CH3CN)] (where An = U, Np, or Pu). Extraction of An(VI) with the ligand follows the order U > Pu > Np, likely reflecting the decreased stability of the hexavalent actinide across the series. While the results indicate a promising path toward a one-step process, further improvement in the ligand stability and control of the redox chemistry is required.

5.
Anal Chem ; 90(21): 12761-12767, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30298731

RESUMO

Vapor pressure osmometry presents a convenient method to measure chemical activity. The work presented here was carried out to provide confidence in using this technique for a VPO model that does not utilize the "hanging-drop" method. While validation studies are available for certain models of vapor pressure osmometers, none were located for the UIC Jupiter 833 osmometer. This study addresses that need by providing a comparison between original experimental data on sodium chloride, calcium chloride, and sodium sulfate solutions to values calculated using the Pitzer equations. A comparison is also made for experimental data on sucrose with a literature correlation. This study briefly reviews the assumptions going into the equation used to relate the osmometer signal to the diluent activity in order to identify potential sources of the error and the noise in the data. The experimental data shows that the UIC 833 osmometer yields diluent activity values accurate to an average of 0.02%, allowing calculation of osmotic coefficients and solute activity coefficients. Further studies need to be conducted on the accuracy at concentrations above 1.4 m. Qualitatively, however, comparison suggests the UIC Jupiter 833 osmometer yields more scatter in the experimental data than the Knauer instruments. Using more uniform mesh caps on the thermistors could possibly reduce that scatter. Finally, we show that replacing the glass thermistors with in-house made thermistors with Teflon incorporated in the structure give reproducible results and that certain modifications to the design are possible without losing accuracy in the measurements.

6.
Development ; 142(20): 3519-28, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26395490

RESUMO

Current understanding infers a neural crest origin of thyroid C cells, the major source of calcitonin in mammals and ancestors to neuroendocrine thyroid tumors. The concept is primarily based on investigations in quail-chick chimeras involving fate mapping of neural crest cells to the ultimobranchial glands that regulate Ca(2+) homeostasis in birds, reptiles, amphibians and fishes, but whether mammalian C cell development involves a homologous ontogenetic trajectory has not been experimentally verified. With lineage tracing, we now provide direct evidence that Sox17+ anterior endoderm is the only source of differentiated C cells and their progenitors in mice. Like many gut endoderm derivatives, embryonic C cells were found to coexpress pioneer factors forkhead box (Fox) a1 and Foxa2 before neuroendocrine differentiation takes place. In the ultimobranchial body epithelium emerging from pharyngeal pouch endoderm in early organogenesis, differential Foxa1/Foxa2 expression distinguished two spatially separated pools of C cell precursors with different growth properties. A similar expression pattern was recapitulated in medullary thyroid carcinoma cells in vivo, consistent with a growth-promoting role of Foxa1. In contrast to embryonic precursor cells, C cell-derived tumor cells invading the stromal compartment downregulated Foxa2, foregoing epithelial-to-mesenchymal transition designated by loss of E-cadherin; both Foxa2 and E-cadherin were re-expressed at metastatic sites. These findings revise mammalian C cell ontogeny, expand the neuroendocrine repertoire of endoderm and redefine the boundaries of neural crest diversification. The data further underpin distinct functions of Foxa1 and Foxa2 in both embryonic and tumor development.


Assuntos
Linhagem da Célula , Regulação da Expressão Gênica no Desenvolvimento , Crista Neural/citologia , Glândula Tireoide/citologia , Glândula Tireoide/embriologia , Animais , Calcitonina/metabolismo , Cálcio/metabolismo , Carcinoma Medular/metabolismo , Diferenciação Celular , Endoderma/metabolismo , Transição Epitelial-Mesenquimal , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Fator 3-beta Nuclear de Hepatócito/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Células-Tronco/citologia , Neoplasias da Glândula Tireoide/metabolismo
7.
Sensors (Basel) ; 18(12)2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30558221

RESUMO

The non line-of-sight (NLOS) scenario in urban intersections is critical in terms of traffic safety-a scenario where Vehicle-to-Vehicle (V2V) communication really can make a difference by enabling communication and detection of vehicles around building corners. A few NLOS V2V channel models exist in the literature but they all have some form of limitation, and therefore further research is need. In this paper, we present an alternative NLOS path loss model based on analysis from measured V2V communication channels at 5.9 GHz between six vehicles in two urban intersections. We analyze the auto-correlation of the large scale fading process and the influence of the path loss model on this. In cases where a proper model for the path loss and the antenna pattern is included, the de-correlation distance for the auto-correlation is as low as 2⁻4 m, and the cross-correlation for the large scale fading between different links can be neglected. Otherwise, the de-correlation distance has to be much longer and the cross-correlation between the different communication links needs to be considered separately, causing the computational complexity to be unnecessarily large. With these findings, we stress that vehicular ad-hoc network (VANET) simulations should be based on the current geometry, i.e., a proper path loss model should be applied depending on whether the V2V communication is blocked or not by other vehicles or buildings.

8.
Gerodontology ; 35(4): 290-304, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30129220

RESUMO

OBJECTIVES: To examine the current knowledge on oral health status and dental care of older persons through a systematic mapping of systematic reviews of low or moderate risk of bias. BACKGROUND: Geriatric dentistry covers all aspects of oral health and oral care of older persons. Oral health is part of general health and contributes to a person's physical, psychological and social wellbeing. METHODS: A literature search was performed in three different databases (PubMed, The Cochrane Library and Cinahl) within 12 domains: Dental caries, periodontitis, Orofacial pain and temporomandibular joint (TMJ) pain, mucosal lesions, oral motor function, dry mouth, halitosis, interaction between oral status and other medical conditions, ability to interrelate and communicate, quality of life, ethics and organisation of dental care for older persons. Systematic reviews were identified and scrutinised, highlighting scientific knowledge and knowledge gaps. RESULTS: We included 32 systematic reviews of which 14 were judged to be of low/moderate risk of bias. Most of the domains lack systematic reviews with low or moderate risk of bias. In two of the domains evidence was identified; in institutionalised people aged 65 or older, effective oral hygiene can prevent pneumonia. Furthermore, there is an evidence of a relationship between malnutrition (protein energy-related malnutrition, PEM) and poor appetite and edentulousness. CONCLUSIONS: There is an urgent need for further research and evidence-based knowledge within most domains in geriatric dentistry and in other fields related to oral health and dental care for older persons striving for multi-disciplinary research programmes.


Assuntos
Assistência Odontológica para Idosos , Odontologia Geriátrica , Saúde Bucal , Idoso , Humanos , Higiene Bucal , Revisões Sistemáticas como Assunto
9.
Exp Cell Res ; 344(1): 120-131, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-27108928

RESUMO

Radiotherapy of thyroid cancer with I-131 is abrogated by inherent loss of radioiodine uptake due to loss of sodium iodide symporter (NIS) expression in poorly differentiated tumor cells. It is also known that ionizing radiation per se down-regulates NIS (the stunning effect), but the mechanism is unknown. Here we investigated whether loss of NIS-mediated iodide transport may be elicited by DNA damage. Calicheamicin, a fungal toxin that specifically cleaves double-stranded DNA, induced a full scale DNA damage response mediated by the ataxia-telangiectasia mutated (ATM) kinase in quiescent normal thyrocytes. At sublethal concentrations (<1nM) calicheamicin blocked NIS mRNA expression and transepithelial iodide transport as stimulated by thyrotropin; loss of function occurred at a much faster rate than after I-131 irradiation. KU-55933, a selective ATM kinase inhibitor, partly rescued NIS expression and iodide transport in DNA-damaged cells. Prolonged ATM inhibition in healthy cells also repressed NIS-mediated iodide transport. ATM-dependent loss of iodide transport was counteracted by IGF-1. Together, these findings indicate that NIS, the major iodide transporter of the thyroid gland, is susceptible to DNA damage involving ATM-mediated mechanisms. This uncovers novel means of poor radioiodine uptake in thyroid cells subjected to extrinsic or intrinsic genotoxic stress.


Assuntos
Dano ao DNA , Simportadores/metabolismo , Aminoglicosídeos/farmacologia , Animais , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Transporte Biológico/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Eletrólitos/metabolismo , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Iodetos/metabolismo , Sus scrofa , Simportadores/genética , Glândula Tireoide/citologia , Tireotropina/farmacologia
13.
Chembiochem ; 17(18): 1693-7, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27383542

RESUMO

Engineered enzyme variants of potato epoxide hydrolase (StEH1) display varying degrees of enrichment of (2R)-3-phenylpropane-1,2-diol from racemic benzyloxirane. Curiously, the observed increase in the enantiomeric excess of the (R)-diol is not only a consequence of changes in enantioselectivity for the preferred epoxide enantiomer, but also to changes in the regioselectivity of the epoxide ring opening of (S)-benzyloxirane. In order to probe the structural origin of these differences in substrate selectivity and catalytic regiopreference, we solved the crystal structures for the evolved StEH1 variants. We used these structures as a starting point for molecular docking studies of the epoxide enantiomers into the respective active sites. Interestingly, despite the simplicity of our docking analysis, the apparent preferred binding modes appear to rationalize the experimentally determined regioselectivities. The analysis also identifies an active site residue (F33) as a potentially important interaction partner, a role that could explain the high conservation of this residue during evolution. Overall, our experimental, structural, and computational studies provide snapshots into the evolution of enantioconvergence in StEH1-catalyzed epoxide hydrolysis.


Assuntos
Biocatálise , Evolução Molecular Direcionada , Epóxido Hidrolases/metabolismo , Compostos de Epóxi/metabolismo , Solanum tuberosum/enzimologia , Compostos de Epóxi/química , Hidrólise , Simulação de Acoplamento Molecular , Estrutura Molecular
14.
Exp Cell Res ; 338(2): 127-35, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26384551

RESUMO

Tumor microenvironment influences targeted drug therapy. In this study we compared drug responses to RAF and MEK inhibitors on tumor cell migration in 2D and 3D culture of BRAF(V600E) mutant cell lines derived from human papillary (BCPAP) and anaplastic (SW1736) thyroid carcinomas. Scratch wounding was compared to a double-layered collagen gel model developed for analysis of directed tumor cell invasion during prolonged culture. In BCPAP both PLX4720 and U0126 inhibited growth and migration in 2D and decreased tumor cell survival in 3D. In SW1736 drugs had no effect on migration in 2D but decreased invasion in 3D, however this related to reduced growth. Dual inhibition of BRAF(V600E) and MEK reduced but did not prevent SW1736 invasion although rebound phosphorylation of ERK in response to PLX4720 was blocked by U0126. These findings indicate that anti-tumor drug effects in vitro differ depending on culture conditions (2D vs. 3D) and that the invasive features of anaplastic thyroid cancer depend on non-MEK mechanism(s).


Assuntos
Movimento Celular/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Invasividade Neoplásica/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Transdução de Sinais/efeitos dos fármacos , Carcinoma Anaplásico da Tireoide/tratamento farmacológico , Antineoplásicos/farmacologia , Butadienos/farmacologia , Carcinoma/tratamento farmacológico , Carcinoma/genética , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Movimento Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Humanos , Indóis/farmacologia , Proteínas Quinases Ativadas por Mitógeno/genética , Mutação/efeitos dos fármacos , Mutação/genética , Invasividade Neoplásica/genética , Nitrilas/farmacologia , Fosforilação/efeitos dos fármacos , Transdução de Sinais/genética , Sulfonamidas/farmacologia , Carcinoma Anaplásico da Tireoide/genética
15.
Exp Cell Res ; 326(2): 210-8, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24726885

RESUMO

Normal thyrocytes grown as reconstituted follicles in collagen gel were evaluated for drug effects of small molecule kinase inhibitors on growth factor-induced cell migration in a 3D context. MEK inhibition by U0126 only partially antagonized EGF/serum-induced cell migration from the basal follicular surface into the matrix. Combined treatment with U0126 and LY294002, a PI3K blocker, was necessary to abolish migration. However, exposure to only LY294002 facilitated the response to EGF by breakdown of the original follicular structure. In the same time EGF promoted thyroid cell survival that was compromised by LY294002 in absence of EGF. Cells treated with EGF and LY294002 retained the ability to form follicles. The findings indicate that dual inhibition of MAPK and PI3K/AKT pathways is required to fully block matrix invasion of EGF-stimulated thyroid cells. Conversely, single drug treatment with PI3K inhibitor adversely promotes invasiveness probably by destabilizing the follicular epithelium.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Sistema de Sinalização das MAP Quinases , Fosfatidilinositol 3-Quinases/metabolismo , Glândula Tireoide/citologia , Glândula Tireoide/metabolismo , Animais , Butadienos/farmacologia , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromonas/farmacologia , Inibidores Enzimáticos/farmacologia , Matriz Extracelular/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Morfolinas/farmacologia , Invasividade Neoplásica , Nitrilas/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Suínos , Glândula Tireoide/efeitos dos fármacos , Neoplasias da Glândula Tireoide/etiologia , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Técnicas de Cultura de Tecidos
16.
Cancer Cell Int ; 14(1): 72, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25278811

RESUMO

BACKGROUND: Transforming growth factor beta (TGF-ß) plays major roles in tumorigenesis by regulating cell growth, epithelial-to-mesenchymal transition (EMT), migration/invasion and metastasis. The epithelial markers E-cadherin, claudin-3 and claudin-4, commonly decreased in human adenocarcinomas are actually up regulated during ovarian carcinogenesis. In human ovarian cancer TGF-ß1 may either suppress or promote tumor progression, but whether other TGF-ß isoforms (TGF-ß2 and TGF-ß3) exert similar effects is not known. METHODS: In this study we investigated the ability of the TGF-ß isoforms (TGF-ß1-3) to induce proliferation and migration by BrdU labeling, scratch wound and trans-filter migration assays in the human serous adenocarcinoma cell-line NIH-OVCAR3. Transepithelial resistance was measured and EMT observed by light-microscopy. Expression of adherens-, tight-junction and EMT-related transcription factors was analyzed by qRT-PCR and immunoblotting. RESULTS: All TGF-ß isoforms dose-dependently inhibited NIH-OVCAR3 cell growth, stimulated tumor cell migration with similar efficiency. The mesenchymal marker N-cadherin and claudin-1 expression was induced and occludin down regulated. However, migrating cells retained an epithelial shape and E-cadherin expression. The E-cadherin repressor SNAIL mRNA levels remained low independently of TGF-ß1-3 treatment while ZEB1 expression was enhanced. CONCLUSIONS: TGF-ß1, TGF-ß2 and TGF-ß3 promote migration of NIH-OVCAR3 ovarian cancer cells independently of cell proliferation and without conversion to a complete EMT phenotype. Epithelial ovarian cancer commonly metastasis to the surrounding tissue or inside the peritoneum rather than invading blood vessels to set distance metastasis. Our result raises the question whether ovarian cancer primarily spread via collective migration than via single cell invasion.

17.
Pharmacoepidemiol Drug Saf ; 23(3): 290-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24435842

RESUMO

PURPOSE: The aim of this study was to analyse prescription refill, re-hospitalisation, total mortality, mortality because of suicide and attempted suicide among patients who were taking various types of antipsychotics. METHODS: A population-based cohort study analysed all patients (n=26046) in Sweden who had been treated for schizophrenia from 2006 to 2009 with regard to re-hospitalisation and prescription refill for various types of antipsychotic treatment. A case-control study nested within the cohort analysed all-cause mortality, mortality because of suicide and attempted suicide in relation to antipsychotic use. The study adjusted for history of hospitalisation for psychiatric and medical care, attempted suicide and use of antidepressants. RESULTS: Aripiprazole users were the only ones who showed significantly lower all-cause risks of death, but so few events occurred among users of this relatively new drug that the results should be interpreted with caution. Clozapine users showed lower odds of death by suicide (odds ratio [OR]=0.45 [95%CI 0.20-0.98]) and of attempted suicide (OR=0.44 [0.28-0.70]) than haloperidol users after adjustment for age, sex and year of discharge. Olanzapine users showed approximately the same favourable pattern. Patients who used clozapine were most likely to refill prescriptions and had lower rates of re-hospitalisation. Only one death and 23 cases of agranulocytosis were reported compared with 223 suicides and 831 suicide attempts. An etiologic fraction calculation suggests that the use of clozapine rather than traditional drugs could have prevented 95 suicide attempts during the period. CONCLUSION: Clozapine and olanzapine reduce the risk of suicide, attempted suicide and re-hospitalisation.


Assuntos
Antipsicóticos/administração & dosagem , Clozapina/administração & dosagem , Prescrições de Medicamentos , Hospitalização , Tentativa de Suicídio/prevenção & controle , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Hospitalização/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Tentativa de Suicídio/psicologia , Suécia/epidemiologia , Adulto Jovem
18.
Lakartidningen ; 1212024 Feb 27.
Artigo em Sueco | MEDLINE | ID: mdl-38712675

RESUMO

Anaplastic and poorly differentiated thyroid cancer (ATC, PDTC) are rare and highly aggressive tumors that historically have been associated with a short life expectancy and low chance of cure. Molecular pathology and the introduction of highly effective targeted drugs have revolutionized the possibilities of management of patients with ATC and PDTC, with BRAF and MEK inhibitors as the most prominent example. Here we provide updated recommendations regarding diagnostics and management, including primary surgical management and targeted therapies based on specific molecular pathological findings.


Assuntos
Terapia de Alvo Molecular , Proteínas Proto-Oncogênicas B-raf , Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/diagnóstico , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Carcinoma Anaplásico da Tireoide/tratamento farmacológico , Carcinoma Anaplásico da Tireoide/patologia , Carcinoma Anaplásico da Tireoide/genética , Carcinoma Anaplásico da Tireoide/diagnóstico , Inibidores de Proteínas Quinases/uso terapêutico , Antineoplásicos/uso terapêutico
19.
iScience ; 26(7): 107071, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37534159

RESUMO

Cells of origin in cancer determine tumor phenotypes, but whether lineage-defining transcription factors might influence tissue specificity of tumorigenesis among organs with similar developmental traits are unknown. We demonstrate here that tumor development and progression markedly differ in lung and thyroid targeted by Braf mutation in Nkx2.1CreERT2 mice heterozygous for Nkx2-1. In absence of tamoxifen, non-induced Nkx2.1CreERT2;BrafCA/+ mutants developed multiple full-blown lung adenocarcinomas with a latency of 1-3 months whereas thyroid tumors were rare and constrained, although minute BrafCA activation documented by variant allele sequencing was similar in both tissues. Induced oncogene activation accelerated neoplastic growth only in the lungs. By contrast, NKX2-1+ progenitor cells were equally responsive to constitutive expression of mutant Braf during lung and thyroid development. Both lung and thyroid cells transiently downregulated NKX2-1 in early tumor stages. These results indicate that BRAFV600E-induced tumorigenesis obey organ-specific traits that might be differentially modified by a shared lineage factor.

20.
FEBS J ; 290(2): 379-399, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35997626

RESUMO

Cellobiohydrolases (CBHs) in the glycoside hydrolase family 7 (GH7) (EC3.2.1.176) are the major cellulose degrading enzymes both in industrial settings and in the context of carbon cycling in nature. Small carbohydrate conjugates such as p-nitrophenyl-ß-d-cellobioside (pNPC), p-nitrophenyl-ß-d-lactoside (pNPL) and methylumbelliferyl-ß-d-cellobioside have commonly been used in colorimetric and fluorometric assays for analysing activity of these enzymes. Despite the similar nature of these compounds the kinetics of their enzymatic hydrolysis vary greatly between the different compounds as well as among different enzymes within the GH7 family. Through enzyme kinetics, crystallographic structure determination, molecular dynamics simulations, and fluorometric binding studies using the closely related compound o-nitrophenyl-ß-d-cellobioside (oNPC), in this work we examine the different hydrolysis characteristics of these compounds on two model enzymes of this class, TrCel7A from Trichoderma reesei and PcCel7D from Phanerochaete chrysosporium. Protein crystal structures of the E212Q mutant of TrCel7A with pNPC and pNPL, and the wildtype TrCel7A with oNPC, reveal that non-productive binding at the product site is the dominating binding mode for these compounds. Enzyme kinetics results suggest the strength of non-productive binding is a key determinant for the activity characteristics on these substrates, with PcCel7D consistently showing higher turnover rates (kcat ) than TrCel7A, but higher Michaelis-Menten (KM ) constants as well. Furthermore, oNPC turned out to be useful as an active-site probe for fluorometric determination of the dissociation constant for cellobiose on TrCel7A but could not be utilized for the same purpose on PcCel7D, likely due to strong binding to an unknown site outside the active site.


Assuntos
Celulase , Trichoderma , Celulose 1,4-beta-Celobiosidase/química , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Compostos Cromogênicos , Celulose/metabolismo , Simulação de Dinâmica Molecular , Cinética , Celulase/metabolismo
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