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1.
Am J Surg Pathol ; 48(7): 839-845, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38764379

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) develops from 2 known precursor lesions: a majority (∼85%) develops from pancreatic intraepithelial neoplasia (PanIN), and a minority develops from intraductal papillary mucinous neoplasms (IPMNs). Clinical classification of PanIN and IPMN relies on a combination of low-resolution, 3-dimensional (D) imaging (computed tomography, CT), and high-resolution, 2D imaging (histology). The definitions of PanIN and IPMN currently rely heavily on size. IPMNs are defined as macroscopic: generally >1.0 cm and visible in CT, and PanINs are defined as microscopic: generally <0.5 cm and not identifiable in CT. As 2D evaluation fails to take into account 3D structures, we hypothesized that this classification would fail in evaluation of high-resolution, 3D images. To characterize the size and prevalence of PanINs in 3D, 47 thick slabs of pancreas were harvested from grossly normal areas of pancreatic resections, excluding samples from individuals with a diagnosis of an IPMN. All patients but one underwent preoperative CT scans. Through construction of cellular resolution 3D maps, we identified >1400 ductal precursor lesions that met the 2D histologic size criteria of PanINs. We show that, when 3D space is considered, 25 of these lesions can be digitally sectioned to meet the 2D histologic size criterion of IPMN. Re-evaluation of the preoperative CT images of individuals found to possess these large precursor lesions showed that nearly half are visible on imaging. These findings demonstrate that the clinical classification of PanIN and IPMN fails in evaluation of high-resolution, 3D images, emphasizing the need for re-evaluation of classification guidelines that place significant weight on 2D assessment of 3D structures.


Assuntos
Carcinoma Ductal Pancreático , Imageamento Tridimensional , Neoplasias Intraductais Pancreáticas , Neoplasias Pancreáticas , Humanos , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/classificação , Neoplasias Intraductais Pancreáticas/patologia , Neoplasias Intraductais Pancreáticas/diagnóstico por imagem , Feminino , Carcinoma in Situ/patologia , Carcinoma in Situ/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Idoso , Tomografia Computadorizada por Raios X , Carga Tumoral , Valor Preditivo dos Testes
2.
bioRxiv ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38106231

RESUMO

Methods for spatially resolved cellular profiling using thinly cut sections have enabled in-depth quantitative tissue mapping to study inter-sample and intra-sample differences in normal human anatomy and disease onset and progression. These methods often profile extremely limited regions, which may impact the evaluation of heterogeneity due to tissue sub-sampling. Here, we applied CODA, a deep learning-based tissue mapping platform, to reconstruct the three-dimensional (3D) microanatomy of grossly normal and cancer-containing human pancreas biospecimens obtained from individuals who underwent pancreatic resection. To compare inter- and intra-sample heterogeneity, we assessed bulk and spatially resolved tissue composition in a cohort of two-dimensional (2D) whole slide images (WSIs) and a cohort of thick slabs of pancreas tissue that were digitally reconstructed in 3D from serial sections. To demonstrate the marked under sampling of 2D assessments, we simulated the number of WSIs and tissue microarrays (TMAs) necessary to represent the compositional heterogeneity of 3D data within 10% error to reveal that tens of WSIs and hundreds of TMA cores are sometimes needed. We show that spatial correlation of different pancreatic structures decay significantly within a span of microns, demonstrating that 2D histological sections may not be representative of their neighboring tissues. In sum, we demonstrate that 3D assessments are necessary to accurately assess tissue composition in normal and abnormal specimens and in order to accurately determine neoplastic content. These results emphasize the importance of intra-sample heterogeneity in tissue mapping efforts.

5.
Front Cell Dev Biol ; 8: 592035, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33330472

RESUMO

Erythropoiesis is the most robust cellular differentiation and proliferation system, with a production of ∼2 × 1011 cells per day. In this fine-tuned process, the hematopoietic stem cells (HSCs) generate erythroid progenitors, which proliferate and mature into erythrocytes. During erythropoiesis, mitochondria are reprogrammed to drive the differentiation process before finally being eliminated by mitophagy. In erythropoiesis, mitochondrial dynamics (MtDy) are expected to be a key regulatory point that has not been described previously. We described that a specific MtDy pattern occurs in human erythropoiesis from EPO-induced human CD34+ cells, characterized predominantly by mitochondrial fusion at early stages followed by fission at late stages. The fusion protein MFN1 and the fission protein FIS1 are shown to play a key role in the progression of erythropoiesis. Fragmentation of the mitochondrial web by the overexpression of FIS1 (gain of fission) resulted in both the inhibition of hemoglobin biosynthesis and the arrest of erythroid differentiation, keeping cells in immature differentiation stages. These cells showed specific mitochondrial features as compared with control cells, such as an increase in round and large mitochondrial morphology, low mitochondrial membrane potential, a drop in the expression of the respiratory complexes II and IV and increased ROS. Interestingly, treatment with the mitochondrial permeability transition pore (mPTP) inhibitor, cyclosporin A, rescued mitochondrial morphology, hemoglobin biosynthesis and erythropoiesis. Studies presented in this work reveal MtDy as a hot spot in the control of erythroid differentiation, which might signal downstream for metabolic reprogramming through regulation of the mPTP.

6.
Int J Rheum Dis ; 22(8): 1393-1401, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30968571

RESUMO

BACKGROUND: Inflammatory idiopathic myositis (IIM) comprises a heterogeneous group of systemic muscular diseases that can occur together with other connective tissue diseases (CTD), named overlap myositis (OM). The question of whether OM is a distinct entity still remains controversial. AIM: The present study was conducted to assess the clinical and prognostic differences between patients diagnosed with OM, primary polymyositis (PM) and primary dermatomyositis (DM). METHOD: The study consists of a retrospective longitudinal and multicenter series of IIM patients. Patients were classified as OM, PM and DM. Overlap myositis was defined as patients fulfilling criteria for IIM plus criteria for other CTD (namely systemic sclerosis, systemic lupus erythematosus, mixed connective tissue disease, rheumatoid arthritis and primary Sjögren's syndrome). RESULT: A total of 342 patients were included (98 OM, 137 PM and 107 DM). Overlap myositis patients, in comparison with PM and DM, showed significant differences, with more extramuscular involvement, particularly more arthritis (66%, 34.6% and 48.1%, respectively), puffy fingers (49.5%, 11.1% and 24.3%), sclerodactyly (45.4%, 2.2% and 2%), dysphagia (41.8%, 18.2% and 26.4%), Raynaud phenomenon (65.3%, 16.9% and 19.8%), leucopenia (28.9%, 2.2% and 8.4%), thrombocytopenia (8.2%, 2.2% and 1.9%), interstitial lung disease (ILD) (48%, 35% and 30.8%), renal manifestations (13.4%, 3.7% and 1.9%), and more severe infections (41.3%, 26.7% and 21%). No significant differences were found in survival between groups in log rank test (P = 0.106). Multivariate adjusted survival analyses revealed a worse prognosis for severe infections, ILD and baseline elevation of acute phase reactants. CONCLUSION: Overlap myositis stands out as a distinct entity as compared to PM and DM, featuring more extramuscular involvement and more severe infections. Close monitoring is recommended in this subset for early detection and treatment of possible complications.


Assuntos
Dermatomiosite/diagnóstico , Polimiosite/diagnóstico , Adulto , Idoso , Dermatomiosite/classificação , Dermatomiosite/tratamento farmacológico , Diagnóstico Diferencial , Feminino , Humanos , Fatores Imunológicos/uso terapêutico , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Polimiosite/classificação , Polimiosite/tratamento farmacológico , Valor Preditivo dos Testes , Prognóstico , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Espanha , Terminologia como Assunto
7.
Clin Rheumatol ; 38(3): 803-815, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30392161

RESUMO

OBJECTIVE: To study prognostic factors in different types of idiopathic inflammatory myopathies (IIM) associated with interstitial lung disease (ILD). PATIENTS AND METHODS: Multicenter retrospective study of a Spanish cohort of patients diagnosed with IIM. Patients were classified into four categories: polymyositis (PM), dermatomyositis (DM), antisynthetase syndrome (ASS), and overlap myositis (OM). Sociodemographic data, clinical characteristics, antibodies, and treatments were collected. Cox regression models were calculated to identify factors associated with mortality, the necessity for long-term oxygen therapy (LTOT), and deterioration in respiratory function tests (RFT). RESULTS: The number of patients included was 478, of whom 112 (23.4%) suffered from ILD: 17% PM, 16% DM, 45% ASS, and 22% OM. Factors associated with mortality in the multivariate analysis were clinically meaningful progression of ILD after 3 months (CMP 3m) (hazard ratio (HR) 9.48, p = 0.005), severe infections (HR 6.41, p = 0.016), heliotrope erythema (HR 31.1, p = 0.002), delay in diagnosis (HR 1.29; p = 0.011), and Raynaud's phenomenon (HR 11.9, p = 0.007). However, being female (HR 0.19, p = 0.044) and positivity solely for ANAs (HR 0.08, p = 0.008) presented a protective effect. CMP 3m (HR 22.7, p = 0.027) was associated with the need for LTOT, while basal aldolase (HR 0.90; p = 0.049) had a protective effect. Likewise, joint manifestations (HR 0.04, p = 0.034) were shown to reduce risk of deterioration in RFT. CONCLUSIONS: CMP 3m, severe infections, delay in diagnosis, heliotrope erythema, and Raynaud's phenomenon were identified as factors of poor prognosis in different IIM associated with ILD.


Assuntos
Doenças Pulmonares Intersticiais/fisiopatologia , Mortalidade , Miosite/fisiopatologia , Oxigenoterapia/estatística & dados numéricos , Adolescente , Adulto , Idoso , Anticorpos Antinucleares/imunologia , Diagnóstico Tardio/estatística & dados numéricos , Dermatomiosite/epidemiologia , Dermatomiosite/imunologia , Dermatomiosite/fisiopatologia , Progressão da Doença , Eritema/epidemiologia , Feminino , Frutose-Bifosfato Aldolase/metabolismo , Humanos , Infecções/epidemiologia , Estimativa de Kaplan-Meier , Estudos Longitudinais , Doenças Pulmonares Intersticiais/epidemiologia , Doenças Pulmonares Intersticiais/terapia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Miosite/epidemiologia , Miosite/imunologia , Polimiosite/epidemiologia , Polimiosite/imunologia , Polimiosite/fisiopatologia , Prognóstico , Modelos de Riscos Proporcionais , Fatores de Proteção , Capacidade de Difusão Pulmonar , Doença de Raynaud/epidemiologia , Testes de Função Respiratória , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Espanha/epidemiologia , Capacidade Vital , Adulto Jovem
8.
Rheumatol Int ; 37(11): 1853-1861, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28866745

RESUMO

The present study was undertaken to assess mortality, causes of death, and associated prognostic factors in a large cohort of patients diagnosed with idiopathic inflammatory myositis (IIM) from Spain. A retrospective longitudinal study was carried out in 467 consecutive patients with IIM, identified from 12 medical centers. Patients were classified as primary polymyositis, primary dermatomyositis (DM), overlap myositis, cancer-associated myositis (CAM), and juvenile idiopathic inflammatory myopathies. A total of 113 deaths occurred (24%) after a median follow-up time of 9.7 years. In the overall cohort, the 2-, 5-, and 10-year survival probabilities were 91.9, 86.7, and 77%, respectively. Main causes of death were infections and cancer (24% each). Multivariate model revealed that CAM (HR = 24.06), OM (HR = 12.00), DM (HR = 7.26), higher age at diagnosis (HR = 1.02), severe infections (HR = 3.66), interstitial lung disease (HR = 1.61), and baseline elevation of acute phase reactants (HR = 3.03) were associated with a worse prognosis, while edema of the hands (HR = 0.39), female gender (HR = 0.39), and longer disease duration (HR = 0.73) were associated with a better prognosis. The standardized mortality ratio was 1.56 (95% CI 1.28-1.87) compared to the Spanish general population. Our findings indicate that IIM has a high long-term mortality, with an excess of mortality compared to the Spanish population. A more aggressive therapy may be required in IIM patients presenting with poor predictive factors.


Assuntos
Miosite/mortalidade , Adulto , Idoso , Causas de Morte , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
9.
Surg. cosmet. dermatol. (Impr.) ; 9(2): 156-159, abr.-jun. 2017. ilus., tab.
Artigo em Inglês, Português | LILACS | ID: biblio-880238

RESUMO

Introdução: A acne é doença multifatorial em que se evidenciam lesões inflamatórias constituídas por: pápulas, pústulas e comedões. É mais comum dos 11 aos 30 anos de idade, ocorrendo em várias regiões do corpo em que há altas concentrações de unidades pilossebáceas. A acne tem diferentes classificações e tratamentos. Recentemente, os fatores de crescimento de plaquetas têm sido indicados como terapia alternativa para cicatrizes da acne. Objetivo: Descrever o caso de paciente com acne nódulo-cística e cicatrizes de acne graus 1, 2 e 3b tratado com plasma rico em plaquetas e, ao mesmo tempo, destacar a eficácia do tratamento. Métodos: Aplicação de plasma rico em plaquetas durante três meses no lado esquerdo da face de um paciente. Resultados: De acordo com avaliações clínica e fotográfica, houve melhora na aparência e qualidade da pele, observando-se menor número de lesões e diminuição de fenômenos dolorosos. Conclusões: O presente estudo demonstrou a eficácia do plasma rico em plaquetas como tratamento para a acne assim como suas cicatrizes.


Introduction: Acne is a multifactorial disease where inflammatory lesions usually appear as papules, pustules and comedones. It is more common in people aged between 11 and 30 years, and occurs in various body sites where there are high concentrations of pilosebaceous glands. Acne has different classifications and treatments. More recently, platelet growth factors have been used as an alternative therapy for acne scars. Objective: The present study is aimed at describing a case of nodule-cystic acne and acne scars Grades 1, 2 and 3b treated with platelet rich plasma and highlighting the effectiveness of the treatment. Methods: Platelet rich plasma was applied for three months in the left side of the face of a patient bearing acne. Results: In the clinical and photographic evaluations, there was improvement in the skin appearance and quality, less number of lesions and decrease of pain. Conclusions: The present study has demonstrated the effectiveness of platelet rich plasma as a treatment for acne and resulting scars.

10.
Biometals ; 29(4): 743-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27460450

RESUMO

Trypanosoma cruzi (T. cruzi) is the parasite that causes Chagas disease. Nifurtimox is the most used drug against the T. cruzi, this drug increases intermediaries nitro group, being mainly responsible for the high toxicity component, for this reason it is important to study new organic compounds and thus improve therapeutic strategies against Chagas disease. The electronic effects of ferrocenyl and cyrhetrenyl fragments were investigated by DFT calculation. A close correlation was found between HOMO-LUMO gap of nitro radical NO 2 (-) with the experimental reduction potential found for nitro group and IC50 of two forms the T. cruzi (epimastigote and trypomastigote). The IC50 on human hepatoma cells is higher for both compounds compared to IC50 demonstrated in the two forms the T. cruzi, and additionally show reactive oxygen species release. The information obtained in this paper could generate two new drugs with anti-T. cruzi activity, but additional studies are needed.


Assuntos
Compostos Ferrosos/farmacologia , Compostos Organometálicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Rênio/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Compostos Ferrosos/química , Células Hep G2 , Humanos , Compostos Organometálicos/química , Testes de Sensibilidade Parasitária , Rênio/química , Tripanossomicidas/química , Trypanosoma cruzi/metabolismo
11.
Int J Mol Sci ; 17(2): 260, 2016 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-26907262

RESUMO

Hepatocellular carcinoma (HCC) is one of the most commonly diagnosed cancers worldwide. Chemoprevention of HCC can be achieved through the use of natural or synthetic compounds that reverse, suppress or prevent the development of cancer progression. In this study, we investigated the antiproliferative effects and the mechanism of action of two compounds, 2,3,4'-trimethoxy-2'-hydroxy-chalcone (CH1) and 3'-bromo-3,4-dimethoxy-chalcone (CH2), over human hepatoma cells (HepG2 and Huh-7) and cultured mouse hepatocytes (HepM). Cytotoxic effects were observed over the HepG2 and Huh-7, and no effects were observed over the HepM. For HepG2 cells, treated separately with each chalcone, typical apoptotic laddering and nuclear condensation were observed. Additionally, the caspases and Bcl-2 family proteins activation by using Western blotting and immunocytochemistry were studied. Caspase-8 was not activated, but caspase-3 and -9 were both activated by chalcones in HepG2 cells. Chalcones also induced reactive oxygen species (ROS) accumulation after 4, 8 and 24 h of treatment in HepG2 cells. These results suggest that apoptosis in HepG2 was induced through: (i) a caspase-dependent intrinsic pathway; and (ii) by alterations in the cellular levels of Bcl-2 family proteins, and also, that the chalcone moiety could be a potent candidate as novel anticancer agents acting on human hepatomas.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/metabolismo , Caspases/metabolismo , Chalconas/farmacologia , Neoplasias Hepáticas/metabolismo , Animais , Apoptose , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos
12.
Nanoscale Res Lett ; 11(1): 66, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26847692

RESUMO

Poly(amidoamine) dendrimers are the most recognized class of dendrimer. Amino-terminated (PAMAM-NH2) and hydroxyl-terminated (PAMAM-OH) dendrimers of generation 4 are widely used, since they are commercially available. Both have different properties, mainly based on their different overall charges at physiological pH. Currently, an important function of dendrimers as carriers of short single-stranded DNA has been applied. These molecules, known as antisense oligonucleotides (asODNs), are able to inhibit the expression of a target mRNA. Whereas PAMAM-NH2 dendrimers have shown to be able to transfect plasmid DNA, PAMAM-OH dendrimers have not shown the same successful results. However, little is known about their interaction with shorter and more flexible molecules such as asODNs. Due to several initiatives, the use of these neutral dendrimers as a scaffold to introduce other functional groups has been proposed. Because of its low cytotoxicity, it is relevant to understand the molecular phenomena involving these types of dendrimers. In this work, we studied the behavior of an antisense oligonucleotide in presence of both types of dendrimers using molecular dynamics simulations, in order to elucidate if they are able to form stable complexes. In this manner, we demonstrated at atomic level that PAMAM-NH2, unlike PAMAM-OH, could form a well-compacted complex with asODN, albeit PAMAM-OH can also establish stable interactions with the oligonucleotide. The biological activity of asODN in complex with PAMAM-NH2 dendrimer was also shown. Finally, we revealed that in contact with PAMAM-OH, asODN remains outside the cells as TIRF microscopy results showed, due to its poor interaction with this dendrimer and cell membranes.

15.
Santiago de Chile; s.n; 2012. 41 p. tab, graf.
Tese em Espanhol | LILACS, MOSAICO - Saúde integrativa | ID: biblio-878514

RESUMO

Las plantas poseen diferentes tipos de antioxidantes, entre ellos compuestos polifenólicos y azufrados; entre estos últimos, GSH y cisteína, principales antioxidantes no enzimáticos de la célula animal. La capacidad antioxidante de los preparados herbales depende de numerosas variables, entre ellas, la parte de la planta seleccionada y el proceso de extracción. En este trabajo se analizó la actividad antioxidante de diferentes extractos herbales de los cuales se recibió sólo los nombres que mencionamos a continuación: Gel Aloe Vera, Phytopol Calafate, Phytopol Equisetum, Phytopol Murtilla, Phytopol Abedul, Phytopol Caléndula, Phytopol Romero, Phytopol Matico y Phytopol Avellano. Como sistema biológico, se utilizaron microsomas hepáticos de rata y como sistema pro-oxidante, Cu2+/ascorbato. Se ensayó la capacidad de los extractos de prevenir la lipoperoxidación microsómica y la disminución de los tioles microsómicos, ambos fenómenos inducidos por el sistema Cu2+/ascorbato. Se evaluó además, la capacidad de quelar iones Cu2+ mediante el cambio del espectro de absorbancia de este ion y la capacidad de inhibir la actividad de la GSH-transferásica microsómica, enzima cuya forma activa es el dímero -S-S-.Los resultados mostraron gran diversidad en los efectos antioxidantes ensayados y falta de correlación entre las actividades antioxidantes y la concentración de polifenoles totales de los extractos. Por ejemplo, Phytopol matico que contenía la mayor concentración de polifenoles, no fue el mejor antilipoperoxidante, pero si en las otras actividades medidas. Estos resultados indicarían diversidad en la calidad y cantidad de los antioxidantes presentes en cada uno de los extractos. Esta diversidad nos parece que apoya el uso de extractos polivalentes como estrategia terapéutica asociada a enfermedades que reconocidamente, están asociadas a estrés oxidativo.


Assuntos
Oxirredução , Calendula , Equisetum , Berberis , Betula , Corylus , Buddleja , Aloe , Extratos Vegetais , Modelos Animais
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