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1.
Rozhl Chir ; 102(9): 345-351, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38286662

RESUMO

Lung transplantation has become a standardized and widely accepted treatment modality for selected end-stage lung diseases. Many factors influ- ence the long-term survival of patients after lung transplantation. One of the most important is clearly the development of chronic lung allograft dysfunction (CLAD). This review summarizes current knowledge of the histopathology of CLAD and its clinical characteristics. It also describes lung re-transplantation as the only causal therapy, its possible complications, and outcomes in standard and high-urgency patients awaiting a suitable organ with extracorporeal membrane oxygenation support. Fundoplication is an important surgical modality potentially leading to an improvement of the patients' condition. The indications and outcomes of this surgical procedure are discussed in a separate chapter. In addition, several nonsurgical treatment options aimed at slowing the progression of CLAD are outlined, as well as ongoing research focused on extending the life of these patients.


Assuntos
Transplante de Pulmão , Pulmão , Humanos , Transplante de Pulmão/efeitos adversos , Fundoplicatura , Aloenxertos , Estudos Retrospectivos , Doença Crônica
2.
Rozhl Chir ; 100(3): 138-142, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33910360

RESUMO

Paragangliomas represent a group of neuroendocrine tumours which occur in various localizations. Most of them produce catecholamines, and in advanced cases present with typical symptoms and signs such as palpitations, headache and hypertension. The only curative treatment is radical resection. About one-quarter of paragangliomas are malignant, defined by the presence of distant metastases. There are multiple treatment options for unresectable metastatic tumours. They include radionuclid therapy, chemotherapy, and radiotherapy, although none of them are curative. Cytoreductive surgery can also be considered, especially when the goal is to decrease symptoms related to advanced disease. We present a rare case of a large paraganglioma of the left retroperitoneum. Despite radical surgery, early recurrence of the disease was observed.


Assuntos
Paraganglioma , Humanos , Paraganglioma/diagnóstico por imagem , Paraganglioma/cirurgia
3.
Osteoarthritis Cartilage ; 28(11): 1482-1491, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32739340

RESUMO

OBJECTIVE: Because the literature relating to the influence of degeneration on the viscoelasticity and tissue composition of human lateral menisci remains contradictory or completely lacking, the aim of this study was to fill these gaps by comprehensively characterising the biomechanical properties of menisci with regard to the degree of degeneration. DESIGN: Meniscal tissue from 24 patients undergoing a total knee replacement was collected and the degeneration of each region classified according to Pauli et al. For biomechanical characterisation, compression and tensile tests were performed. Additionally, the water content was determined and infrared (IR) spectroscopy was applied to detect changes in the structural composition, particularly of the proteoglycan and collagen content. RESULTS: With an increasing degree of degeneration, a significant decrease of the equilibrium modulus was detected, while simultaneously the water content and the hydraulic permeability significantly increased. However, the tensile modulus displayed a tendency to decrease with increasing degeneration, which might be due to the significantly decreasing amount of collagen content identified by the IR measurements. CONCLUSION: The findings of the current study may contribute to the understanding of meniscus degeneration, showing that degenerative processes appear to mainly worsen viscoelastic properties of the inner circumference by disrupting the collagen integrity.


Assuntos
Artroplastia do Joelho , Doenças das Cartilagens/fisiopatologia , Colágeno , Meniscos Tibiais/fisiopatologia , Osteoartrite do Joelho/fisiopatologia , Proteoglicanas , Idoso , Fenômenos Biomecânicos , Doenças das Cartilagens/metabolismo , Doenças das Cartilagens/patologia , Força Compressiva , Feminino , Humanos , Masculino , Meniscos Tibiais/metabolismo , Meniscos Tibiais/patologia , Pessoa de Meia-Idade , Osteoartrite do Joelho/metabolismo , Osteoartrite do Joelho/patologia , Análise Espectral , Resistência à Tração
4.
Bone Joint J ; 101-B(8): 1024-1031, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31362545

RESUMO

AIMS: The aim of this study was to determine the risk of local recurrence and survival in patients with osteosarcoma based on the proximity of the tumour to the major vessels. PATIENTS AND METHODS: A total of 226 patients with high-grade non-metastatic osteosarcoma in the limbs were investigated. Median age at diagnosis was 15 years (4 to 67) with the ratio of male to female patients being 1.5:1. The most common site of the tumour was the femur (n = 103) followed by tibia (n = 66). The vascular proximity was categorized based on the preoperative MRI after neoadjuvant chemotherapy into four types: type 1 > 5 mm; type 2 ≤ 5 mm, > 0 mm; type 3 attached; type 4 surrounded. RESULTS: Limb salvage rate based on the proximity type was 92%, 88%, 51%, and 0% for types 1 to 4, respectively, and the overall survival at five years was 82%, 77%, 57%, and 67%, respectively (p < 0.001). Local recurrence rate in patients with limb-salvage surgery was 7%, 8%, and 22% for the types 1 to 3, respectively (p = 0.041), and local recurrence at the perivascular area was observed in 1% and 4% for type 2 and 3, respectively. The mean microscopic margin to the major vessels was 6.9 mm, 3.0 mm, and 1.4 mm for types 1 to 3, respectively. In type 3, local recurrence-free survival with limb salvage was significantly poorer compared with amputation (p = 0.025), while the latter offered no overall survival benefit. In this group of patients, factors such as good response to chemotherapy or limited vascular attachment to less than half circumference or longitudinal 10 mm reduced the risk of local recurrence. CONCLUSION: The proximity of osteosarcoma to major blood vessels is a poor prognostic factor for local control and survival. Amputation offers better local control for tumours attached to the blood vessels but does not improve survival. Limb salvage surgery offers similar local control if the tumour attachment to blood vessels is limited. Cite this article: Bone Joint J 2019;101-B:1024-1031.


Assuntos
Vasos Sanguíneos/diagnóstico por imagem , Neoplasias Femorais/cirurgia , Imageamento por Ressonância Magnética , Recidiva Local de Neoplasia/etiologia , Osteossarcoma/cirurgia , Cuidados Pré-Operatórios/métodos , Tíbia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Neoplasias Femorais/diagnóstico por imagem , Neoplasias Femorais/mortalidade , Neoplasias Femorais/patologia , Seguimentos , Humanos , Salvamento de Membro , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/mortalidade , Osteossarcoma/diagnóstico por imagem , Osteossarcoma/mortalidade , Osteossarcoma/patologia , Prognóstico , Estudos Retrospectivos , Medição de Risco , Análise de Sobrevida , Tíbia/diagnóstico por imagem , Tíbia/patologia , Tíbia/cirurgia , Adulto Jovem
5.
Dent Mater ; 34(3): 442-451, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29233539

RESUMO

OBJECTIVES: To investigate the tubule occlusion and remineralization potential of a novel toothpaste with active tetracalcium phosphate/monetite mixtures under de/remineralization cycling. METHODS: Dentin de/remineralization cycling protocol consisted of demineralization in 1% citric acid at pH 4.6 with following remineralization with toothpastes and soaking in artificial saliva. Effectiveness of toothpastes to promote remineralization was evaluated by measurement of microhardness recovery, analysis of surface roughness, thickness of coating and scanning electron microscopy. RESULTS: The novel tetracalcium phosphate/monetite dentifrice had comparable remineralization potential as commercial calcium silicate/phosphate (SENSODYNE®) and magnesium aluminum silicate (Colgate®) toothpastes and significantly higher than control saliva (p<0.02). Surface roughness was significantly lower after treatment with prepared and SENSODYNE® dentifirice (p<0.05). The coatings on dentin surfaces was significantly thicker after applying toothpastes as compared to negative control (p<0.001). CONCLUSIONS: The new fluoride toothpaste formulation with bioactive tetracalcium phosphate/monetite calcium phosphate mixture effectively occluded dentin tubules and showed good dentin remineralization potential under de/remineralization cycling. It could replace professional powder preparation based on this mixture. It was demonstrated that prepared dentifrice had comparable properties with commercial fluoride calcium silicate/phosphate or magnesium aluminum silicate dentifrices.


Assuntos
Fosfatos de Cálcio/farmacologia , Dentina/efeitos dos fármacos , Remineralização Dentária/métodos , Cremes Dentais/farmacologia , Compostos de Alumínio/farmacologia , Combinação de Medicamentos , Fluoretos/farmacologia , Testes de Dureza , Humanos , Técnicas In Vitro , Compostos de Magnésio/farmacologia , Microscopia Eletrônica de Varredura , Nitratos/farmacologia , Fosfatos/farmacologia , Saliva Artificial , Silicatos/farmacologia , Propriedades de Superfície
6.
Oncogene ; 36(40): 5620-5630, 2017 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-28581527

RESUMO

Basal-like/triple-negative breast cancers (TNBCs) are among the most aggressive forms of breast cancer, and disproportionally affects young premenopausal women and women of African descent. Patients with TNBC suffer a poor prognosis due in part to a lack of molecularly targeted therapies, which represents a critical barrier for effective treatment. Here, we identify EphA2 receptor tyrosine kinase as a clinically relevant target for TNBC. EphA2 expression is enriched in the basal-like molecular subtype in human breast cancers. Loss of EphA2 function in both human and genetically engineered mouse models of TNBC reduced tumor growth in culture and in vivo. Mechanistically, targeting EphA2 impaired cell cycle progression through S-phase via downregulation of c-Myc and stabilization of the cyclin-dependent kinase inhibitor p27/KIP1. A small molecule kinase inhibitor of EphA2 effectively suppressed tumor cell growth in vivo, including TNBC patient-derived xenografts. Thus, our data identify EphA2 as a novel molecular target for TNBC.


Assuntos
Ciclo Celular , Efrina-A2/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Animais , Benzamidas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Efrina-A2/antagonistas & inibidores , Efrina-A2/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Recidiva Local de Neoplasia , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-myb/metabolismo , Receptor EphA2 , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/terapia , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Nanotechnology ; 27(25): 254001, 2016 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-27242024

RESUMO

We report high photovoltaic performance of a novel donor-acceptor (D-A) conjugated polymer poly[2,6[4,8-bis(2-ethyl-hexyl)benzo[1,2-b;4,5-b']dithiophene-co-2,5-thiophene-co-4,7[5,6-bis-octyloxy-benzo[1,2,5]thiadiazole]-co-2,5-thiophene] (PBDTTBTZT) in bulk heterojunctions with [6,6]-phenyl-C71-butyric acid methyl ester (PC70BM). A power conversion efficiency (PCE) of more than 7% is obtained for optimized charge-extracting electrodes. Upon application of thermal stress via annealing, a superior thermal stability is demonstrated as compared to poly[N-9″-hepta-decanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)] (PCDTBT).

8.
Oncogene ; 34(30): 3968-76, 2015 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-25284585

RESUMO

Phosphatidylinositol 3-kinase (PI3K) promotes cancer cell survival, migration, growth and proliferation by generating phosphatidylinositol 3,4,5-trisphosphate (PIP3) in the inner leaflet of the plasma membrane. PIP3 recruits pleckstrin homology domain-containing proteins to the membrane to activate oncogenic signaling cascades. Anticancer therapeutics targeting the PI3K/AKT/mTOR (mammalian target of rapamycin) pathway are in clinical development. In a mass spectrometric screen to identify PIP3-regulated proteins in breast cancer cells, levels of the Rac activator PIP3-dependent Rac exchange factor-1 (P-REX1) increased in response to PI3K inhibition, and decreased upon loss of the PI3K antagonist phosphatase and tensin homolog (PTEN). P-REX1 mRNA and protein levels were positively correlated with ER expression, and inversely correlated with PI3K pathway activation in breast tumors as assessed by gene expression and phosphoproteomic analyses. P-REX1 increased activation of Rac1, PI3K/AKT and MEK/ERK signaling in a PTEN-independent manner, and promoted cell and tumor viability. Loss of P-REX1 or inhibition of Rac suppressed PI3K/AKT and MEK/ERK, and decreased viability. P-REX1 also promoted insulin-like growth factor-1 receptor activation, suggesting that P-REX1 provides positive feedback to activators upstream of PI3K. In support of a model where PIP3-driven P-REX1 promotes both PI3K/AKT and MEK/ERK signaling, high levels of P-REX1 mRNA (but not phospho-AKT or a transcriptomic signature of PI3K activation) were predictive of sensitivity to PI3K inhibitors among breast cancer cell lines. P-REX1 expression was highest in estrogen receptor-positive breast tumors compared with many other cancer subtypes, suggesting that neutralizing the P-REX1/Rac axis may provide a novel therapeutic approach to selectively abrogate oncogenic signaling in breast cancer cells.


Assuntos
Neoplasias da Mama/metabolismo , Fatores de Troca do Nucleotídeo Guanina/fisiologia , Sistema de Sinalização das MAP Quinases , Receptores de Fatores de Crescimento/metabolismo , Animais , Neoplasias da Mama/patologia , Sobrevivência Celular , Retroalimentação Fisiológica , Feminino , Humanos , Células MCF-7 , Camundongos Endogâmicos NOD , Camundongos SCID , Mutação , Transplante de Neoplasias , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas rac de Ligação ao GTP/metabolismo
9.
Vet Comp Oncol ; 13(1): 70-6, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23451809

RESUMO

Completeness of mast cell tumour (MCT) excision is determined by assessment of histologically tumour-free margins (HTFM). The HTFM width necessary to prevent local recurrence (LR), recognized as histologic safety margin (HSM) in human oncology, has not been defined. We hypothesized that HTFM width would correlate with risk for LR and high-grade tumours would require wider HTFM than low-grade tumours. Records of dogs with completely excised MCTs were included. Signalment, two-tier tumour grade, tumour size, HTFM width, recurrence and therapy data was collected. High-grade (n = 39) tumours were more likely to recur than low-grade (n = 51) tumours (35.9% versus 3.9%), P < 0.0001, with no association between HTFM width and LR. Twenty-nine percent of low-grade tumours had HTFM less than 3 mm; none recurred. Narrow (≤3 mm) histologic margins are likely adequate to prevent LR of low-grade tumours. High-grade tumours have significant risk of LR regardless of HTFM width.


Assuntos
Doenças do Cão/cirurgia , Mastocitoma/veterinária , Gradação de Tumores , Recidiva Local de Neoplasia/veterinária , Animais , Doenças do Cão/classificação , Cães , Mastocitoma/classificação , Mastocitoma/cirurgia , Estudos Retrospectivos
10.
Vet Pathol ; 50(4): 704-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23269349

RESUMO

Osteosarcoma is the most common bone tumor in dogs. However, current literature focuses primarily on appendicular osteosarcoma. This study examined the prognostic value of histological and clinical factors in flat and irregular bone osteosarcomas and hypothesized that clinical factors would have a significant association with survival time while histological factors would not. All osteosarcoma biopsy samples of the vertebra, rib, sternum, scapula, or pelvis were reviewed while survival information and clinical data were obtained from medical records, veterinarians, and owners. Forty-six dogs were included in the analysis of histopathological variables and 27 dogs with complete clinical data were included in the analysis of clinical variables. In the histopathologic cox regression model, there was no significant association between any histologic feature of osteosarcoma, including grade, and survival time. In the clinical cox regression model, there was a significant association between the location of the tumor and survival time as well as between the percent elevation of alkaline phosphatase (ALP) above normal and survival time. Controlling for ALP elevation, dogs with osteosarcoma located in the scapula had a significantly greater hazard for death (2.8) compared to dogs with tumors in other locations. Controlling for tumor location, every 100% increase in ALP from normal increased the hazard for death by 1.7. For canine osteosarcomas of the flat and irregular bones, histopathological features, including grade do not appear to be rigorous predictors of survival. Clinical variables such as increased ALP levels and tumor location in the scapula were associated with decreased survival times.


Assuntos
Fosfatase Alcalina/metabolismo , Neoplasias Ósseas/veterinária , Doenças do Cão/patologia , Osteossarcoma/veterinária , Animais , Biópsia/veterinária , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/patologia , Doenças do Cão/mortalidade , Cães , Feminino , Entrevistas como Assunto , Masculino , Índice Mitótico/veterinária , Necrose/veterinária , Gradação de Tumores/veterinária , Osteossarcoma/mortalidade , Osteossarcoma/patologia , Pennsylvania , Prognóstico , Escápula/patologia , Fatores de Tempo
11.
Br J Cancer ; 106(1): 148-56, 2012 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-22045191

RESUMO

BACKGROUND: Treatment with epidermal growth factor receptor (EGFR) inhibitors can result in clinical response in non-small-cell lung cancer (NSCLC) and pancreatic ductal adenocarcinoma (PDAC) for some unselected patients. EGFR and KRAS mutation status, amplification of EGFR, or gene expression predictors of response can forecast sensitivity to EGFR inhibition. METHODS: Using an NSCLC cell line model system, we identified and characterised microRNA (miRNA) gene expression that predicts response to EGFR inhibition. RESULTS: Expression of 13 miRNA genes predicts response to EGFR inhibition in cancer cell lines and tumours, and discriminates primary from metastatic tumours. Signature genes target proteins that are enriched for epithelial-to-mesenchymal transition (EMT) genes. Epithelial-to-mesenchymal transition predicts EGFR inhibitor resistance and metastatic behaviour. The EMT transcription factor, ZEB1, shows altered expression in erlotinib-sensitive NSCLC and PDAC, where many signature miRNA genes are upregulated. Ectopic expression of mir-200c alters expression of EMT proteins, sensitivity to erlotinib, and migration in lung cells. Treatment with TGFß1 changes expression of signature miRNA and EMT proteins and modulates migration in lung cells. CONCLUSION: From these data, we hypothesise that the tumour microenvironment elicits TGFß1 and stimulates a miRNA gene expression program that induces resistance to anti-EGFR therapy and drives lung tumour cells to EMT, invasion, and metastasis.


Assuntos
Antineoplásicos/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Perfilação da Expressão Gênica , MicroRNAs/genética , Neoplasias Epiteliais e Glandulares/patologia , Quinazolinas/farmacologia , Linhagem Celular Tumoral , Receptores ErbB/antagonistas & inibidores , Cloridrato de Erlotinib , Humanos
12.
Anal Quant Cytol Histol ; 16(5): 321-31, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7840838

RESUMO

An expert system for teaching cytopathologic skills is described. It uses Tao's cytologic criteria as graded feature parameters for comparison against a set of expert descriptors of known carcinomas. The system scores each diagnosis according to the degree of agreement along each feature axis. The system also allows the user to compare his/her description with that of the expert for any of the tumor entities. The expert knowledge base is abstracted into a numerical matrix within the system. This matrix is used for parameter comparison and score interpretation. This design is simple and compact, allowing portability and broad compatibility for small personal computers. Although testing is only at the initial stages, preliminary studies have shown that the system provides reproducible, consistent results. It is useful as a teaching tool for students, residents and staff pathologists.


Assuntos
Sistemas Inteligentes , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Biologia Celular/educação , Citoplasma/patologia , Humanos
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