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1.
Am J Physiol Cell Physiol ; 320(5): C902-C915, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33689480

RESUMO

Spleen tyrosine kinase (Syk) and Bruton's tyrosine kinase (BTK) play critical roles in platelet physiology, facilitating intracellular immunoreceptor tyrosine-based activation motif (ITAM)-mediated signaling downstream of platelet glycoprotein VI (GPVI) and GPIIb/IIIa receptors. Small molecule tyrosine kinase inhibitors (TKIs) targeting Syk and BTK have been developed as antineoplastic and anti-inflammatory therapeutics and have also gained interest as antiplatelet agents. Here, we investigate the effects of 12 different Syk and BTK inhibitors on GPVI-mediated platelet signaling and function. These inhibitors include four Syk inhibitors, Bay 61-3606, R406 (fostamatinib), entospletinib, TAK-659; four irreversible BTK inhibitors, ibrutinib, acalabrutinib, ONO-4059 (tirabrutinib), AVL-292 (spebrutinib); and four reversible BTK inhibitors, CG-806, BMS-935177, BMS-986195, and fenebrutinib. In vitro, TKIs targeting Syk or BTK reduced platelet adhesion to collagen, dense granule secretion, and alpha granule secretion in response to the GPVI agonist cross-linked collagen-related peptide (CRP-XL). Similarly, these TKIs reduced the percentage of activated integrin αIIbß3 on the platelet surface in response to CRP-XL, as determined by PAC-1 binding. Although all TKIs tested inhibited phospholipase C γ2 (PLCγ2) phosphorylation following GPVI-mediated activation, other downstream signaling events proximal to phosphoinositide 3-kinase (PI3K) and PKC were differentially affected. In addition, reversible BTK inhibitors had less pronounced effects on GPIIb/IIIa-mediated platelet spreading on fibrinogen and differentially altered the organization of PI3K around microtubules during platelets spreading on fibrinogen. Select TKIs also inhibited platelet aggregate formation on collagen under physiological flow conditions. Together, our results suggest that TKIs targeting Syk or BTK inhibit central platelet functional responses but may differentially affect protein activities and organization in critical systems downstream of Syk and BTK in platelets.


Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Plaquetas/efeitos dos fármacos , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Glicoproteínas da Membrana de Plaquetas/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Quinase Syk/antagonistas & inibidores , Tirosina Quinase da Agamaglobulinemia/metabolismo , Plaquetas/enzimologia , Feminino , Humanos , Masculino , Terapia de Alvo Molecular , Adesividade Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Transdução de Sinais , Quinase Syk/metabolismo
2.
Health Technol Assess ; 23(53): 1-108, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31577219

RESUMO

BACKGROUND: Heavy menstrual bleeding (HMB) is a common problem that affects many British women. When initial medical treatment is unsuccessful, the National Institute for Health and Care Excellence recommends surgical options such as endometrial ablation (EA) or hysterectomy. Although clinically and economically more effective than EA, total hysterectomy necessitates a longer hospital stay and is associated with slower recovery and a higher risk of complications. Improvements in endoscopic equipment and training have made laparoscopic supracervical hysterectomy (LASH) accessible to most gynaecologists. This operation could preserve the advantages of total hysterectomy and reduce the risk of complications. OBJECTIVES: To compare the clinical effectiveness and cost-effectiveness of LASH with second-generation EA in women with HMB. DESIGN: A parallel-group, multicentre, randomised controlled trial. Allocation was by remote web-based randomisation (1 : 1 ratio). Surgeons and participants were not blinded to the allocated procedure. SETTING: Thirty-one UK secondary and tertiary hospitals. PARTICIPANTS: Women aged < 50 years with HMB. Exclusion criteria included plans to conceive; endometrial atypia; abnormal cytology; uterine cavity size > 11 cm; any fibroids > 3 cm; contraindications to laparoscopic surgery; previous EA; and inability to give informed consent or complete trial paperwork. INTERVENTIONS: LASH compared with second-generation EA. MAIN OUTCOME MEASURES: Co-primary clinical outcome measures were (1) patient satisfaction and (2) Menorrhagia Multi-Attribute Quality-of-Life Scale (MMAS) score at 15 months post randomisation. The primary economic outcome was incremental cost (NHS perspective) per quality-adjusted life-year (QALY) gained. RESULTS: A total of 330 participants were randomised to each group (total n = 660). Women randomised to LASH were more likely to be satisfied with their treatment than those randomised to EA (97.1% vs. 87.1%) [adjusted difference in proportions 0.10, 95% confidence interval (CI) 0.05 to 0.15; adjusted odds ratio (OR) from ordinal logistic regression (OLR) 2.53, 95% CI 1.83 to 3.48; p < 0.001]. Women randomised to LASH were also more likely to have the best possible MMAS score of 100 (68.7% vs. 54.5%) (adjusted difference in proportions 0.13, 95% CI 0.04 to 0.23; adjusted OR from OLR 1.87, 95% CI 1.31 to 2.67; p = 0.001). Serious adverse event rates were low and similar in both groups (4.5% vs. 3.6%). There was a significant difference in adjusted mean costs between LASH (£2886) and EA (£1282) at 15 months, but no significant difference in QALYs. Based on an extrapolation of expected differences in cost and QALYs out to 10 years, LASH cost an additional £1362 for an average QALY gain of 0.11, equating to an incremental cost-effectiveness ratio of £12,314 per QALY. Probabilities of cost-effectiveness were 53%, 71% and 80% at cost-effectiveness thresholds of £13,000, £20,000 and £30,000 per QALY gained, respectively. LIMITATIONS: Follow-up data beyond 15 months post randomisation are not available to inform cost-effectiveness. CONCLUSION: LASH is superior to EA in terms of clinical effectiveness. EA is less costly in the short term, but expected higher retreatment rates mean that LASH could be considered cost-effective by 10 years post procedure. FUTURE WORK: Retreatment rates, satisfaction and quality-of-life scores at 10-year follow-up will help to inform long-term cost-effectiveness. TRIAI REGISTRATION: Current Controlled Trials ISRCTN49013893. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 53. See the NIHR Journals Library website for further project information.


Almost 1.5 million women in England and Wales suffer from heavy periods. Initial treatment involves tablets or a medicated coil inserted within the womb. Sometimes these treatments do not work and many women need an operation, either endometrial ablation (EA) (removing the lining of the womb) or a full hysterectomy (complete removal of the womb). Previous studies have shown that a full hysterectomy is better at relieving symptoms, but the risk of complications during surgery is higher and patients take longer to recover fully. A newer operation, laparoscopic (keyhole) supracervical hysterectomy, or 'LASH', removes only the part of the womb that causes periods and preserves the cervix or neck of the womb. Women who have LASH can expect fewer complications, earlier discharge from hospital and quicker recovery time. In this study, we compared EA with LASH by asking women who had either procedure how they felt about it 1 year after their operation. Regardless of which operation they had, most women were very satisfied and felt that their symptoms were better. However, the results were much better for those who had the LASH operation, although these women stayed in hospital for longer and took more time to recover. There was no difference in complications from either surgery, although nearly 1 in 20 women who had an EA returned within 1 year to have their wombs removed in a second operation. Although LASH led to a greater improvement in symptoms and levels of satisfaction, it was more expensive in terms of costs incurred by both the health service and society. Given that some women who had an EA are likely to need a second operation in the future, LASH surgery may provide better value for money in the long term.


Assuntos
Técnicas de Ablação Endometrial/métodos , Histerectomia/métodos , Laparoscopia , Menorragia , Adulto , Análise Custo-Benefício , Técnicas de Ablação Endometrial/efeitos adversos , Feminino , Humanos , Histerectomia/efeitos adversos , Laparoscopia/efeitos adversos , Laparoscopia/economia , Pessoa de Meia-Idade , Satisfação do Paciente , Anos de Vida Ajustados por Qualidade de Vida , Avaliação da Tecnologia Biomédica , Reino Unido
3.
Lancet ; 394(10207): 1425-1436, 2019 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-31522846

RESUMO

BACKGROUND: Heavy menstrual bleeding affects 25% of women in the UK, many of whom require surgery to treat it. Hysterectomy is effective but has more complications than endometrial ablation, which is less invasive but ultimately leads to hysterectomy in 20% of women. We compared laparoscopic supracervical hysterectomy with endometrial ablation in women seeking surgical treatment for heavy menstrual bleeding. METHODS: In this parallel-group, multicentre, open-label, randomised controlled trial in 31 hospitals in the UK, women younger than 50 years who were referred to a gynaecologist for surgical treatment of heavy menstrual bleeding and who were eligible for endometrial ablation were randomly allocated (1:1) to either laparoscopic supracervical hysterectomy or second generation endometrial ablation. Women were randomly assigned by either an interactive voice response telephone system or an internet-based application with a minimisation algorithm based on centre and age group (<40 years vs ≥40 years). Laparoscopic supracervical hysterectomy involves laparoscopic (keyhole) surgery to remove the upper part of the uterus (the body) containing the endometrium. Endometrial ablation aims to treat heavy menstrual bleeding by destroying the endometrium, which is responsible for heavy periods. The co-primary clinical outcomes were patient satisfaction and condition-specific quality of life, measured with the menorrhagia multi-attribute quality of life scale (MMAS), assessed at 15 months after randomisation. Our analysis was based on the intention-to-treat principle. The trial was registered with the ISRCTN registry, number ISRCTN49013893. FINDINGS: Between May 21, 2014, and March 28, 2017, we enrolled and randomly assigned 660 women (330 in each group). 616 (93%) of 660 women were operated on within the study period, 588 (95%) of whom received the allocated procedure and 28 (5%) of whom had an alternative surgery. At 15 months after randomisation, more women allocated to laparoscopic supracervical hysterectomy were satisfied with their operation compared with those in the endometrial ablation group (270 [97%] of 278 women vs 244 [87%] of 280 women; adjusted percentage difference 9·8, 95% CI 5·1-14·5; adjusted odds ratio [OR] 2·53, 95% CI 1·83-3·48; p<0·0001). Women randomly assigned to laparoscopic supracervical hysterectomy were also more likely to have the best possible MMAS score of 100 than women assigned to endometrial ablation (180 [69%] of 262 women vs 146 [54%] of 268 women; adjusted percentage difference 13·3, 95% CI 3·8-22·8; adjusted OR 1·87, 95% CI 1·31-2·67; p=0·00058). 14 (5%) of 309 women in the laparoscopic supracervical hysterectomy group and 11 (4%) of 307 women in the endometrial ablation group had at least one serious adverse event (adjusted OR 1·30, 95% CI 0·56-3·02; p=0·54). INTERPRETATION: Laparoscopic supracervical hysterectomy is superior to endometrial ablation in terms of clinical effectiveness and has a similar proportion of complications, but takes longer to perform and is associated with a longer recovery. FUNDING: UK National Institute for Health Research Health Technology Assessment Programme.


Assuntos
Técnicas de Ablação Endometrial , Histerectomia/métodos , Laparoscopia/métodos , Menorragia/cirurgia , Adulto , Técnicas de Ablação Endometrial/efeitos adversos , Feminino , Seguimentos , Humanos , Histerectomia/efeitos adversos , Análise de Intenção de Tratamento , Laparoscopia/efeitos adversos , Pessoa de Meia-Idade , Duração da Cirurgia , Avaliação de Resultados da Assistência ao Paciente , Satisfação do Paciente , Complicações Pós-Operatórias , Qualidade de Vida , Reino Unido
4.
J Opt Soc Am A Opt Image Sci Vis ; 26(10): 2147-62, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19798392

RESUMO

The PN-method is a spectral discretization technique used to obtain numerical solutions to the radiative transport equation. To the best of our knowledge, the PN-method has yet to be generalized to the case of refractive index mismatch in layered slabs used to numerically simulate skin. Our main contribution is the application of a collocation method that takes into account refractive index mismatch at layer interfaces. The stability, convergence, and accuracy of the method are established. Example calculations demonstrating the flexibility of the method are performed.


Assuntos
Luz , Espalhamento de Radiação , Modelos Biológicos , Método de Monte Carlo , Pele/efeitos da radiação , Fatores de Tempo
5.
Appl Opt ; 48(2): 229-41, 2009 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-19137033

RESUMO

Forward-peaked and large-angle scattering approximations of the radiative transport equation give rise to generalized Fokker-Planck equations whose main feature is the replacement of the integral scattering operator with differential operators in the direction-space variables. Using the P(N) method, an appraisal of generalized Fokker-Planck equations due to González-Rodríguez and Kim [Appl. Opt.47, 2599-2609 (2008)], Leakeas and Larsen [Nucl. Sci. Eng.137, 236-250 (2001), and J. Opt. Soc. Am. A20, 92-98 (2003)], and Pomraning [Math. Models Meth. Appl. Sci.2, 21-36 (1992)] is carried out by computing the relative error between the backscattered and transmitted surface flux predicted by the generalized Fokker-Planck equations and the transport equation with Henyey-Greenstein phase function for anisotropies ranging from 0 to 1. Generalized Fokker-Planck equations whose scattering operators incorporate large-angle scattering and possess eigenvalues similar to the integral scattering operator with Henyey-Greenstein phase function are found to minimize the relative error in the limit of unit anisotropy.


Assuntos
Óptica e Fotônica , Algoritmos , Anisotropia , Simulação por Computador , Luz , Modelos Estatísticos , Modelos Teóricos , Método de Monte Carlo , Física/instrumentação , Reprodutibilidade dos Testes , Espalhamento de Radiação
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