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51.
Yuwei Liu Roberto Adamson Mark Galan Basil Hubbi Xuan Liu 《Biomedical optics express》2021,12(5):2647
In this study, we performed dual-modality optical coherence tomography (OCT) characterization (volumetric OCT imaging and quantitative optical coherence elastography) on human breast tissue specimens. We trained and validated a U-Net for automatic image segmentation. Our results demonstrated that U-Net segmentation can be used to assist clinical diagnosis for breast cancer, and is a powerful enabling tool to advance our understanding of the characteristics for breast tissue. Based on the results obtained from U-Net segmentation of 3D OCT images, we demonstrated significant morphological heterogeneity in small breast specimens acquired through diagnostic biopsy. We also found that breast specimens affected by different pathologies had different structural characteristics. By correlating U-Net analysis of structural OCT images with mechanical measurement provided by quantitative optical coherence elastography, we showed that the change of mechanical properties in breast tissue is not directly due to the change in the amount of dense or porous tissue. 相似文献
52.
Cecilia Amparo Reyes Cevallos Daniel Romeu Benchimol de Resende Carla Andreotti Damante Adriana Campos Passanezi SantAna Maria Lcia Rubo de Rezende Sebastio Luiz Aguiar Greghi Mariana Schutzer Ragghianti Zangrando 《Clinical oral investigations》2020,24(3):1197-1203
This study evaluated clinical outcomes of acellular dermal matrix (ADM) allograft compared with autogenous free gingival graft (FGG) for gingival augmentat 相似文献
53.
Victor Alfonso Jimenez Diaz Antonio Tello-Montoliu Raul Moreno Ignacio Cruz Gonzalez Jose Antonio Baz Alonso Rafael Romaguera Eduardo Molina Navarro Pablo Juan Salvadores Emilio Paredes Galan Antonio De Miguel Castro Guillermo Bastos Fernandez Alberto Ortiz Saez Saleta Fernandez Barbeira Sergio Raposeiras Roubin Juan Ocampo Miguez Antonio Serra Peñaranda Mariano Valdes Chavarri Angel Cequier Fillat Andres Iñiguez Romo 《JACC: Cardiovascular Interventions》2019,12(1):22-32
Objectives
The REAC-TAVI (Assessment of platelet REACtivity after Transcatheter Aortic Valve Implantation) trial enrolled patients with aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR) pre-treated with aspirin + clopidogrel, aimed to compare the efficacy of clopidogrel and ticagrelor in suppressing high platelet reactivity (HPR) after TAVI.Background
Current recommendations support short-term use of aspirin + clopidogrel for patients with severe AS undergoing TAVR despite the lack of compelling evidence.Methods
This was a prospective, randomized, multicenter investigation. Platelet reactivity was measured at 6 different time points with the VerifyNow assay (Accriva Diagnostics, San Diego, California). HPR was defined as (P2Y12 reaction units (PRU) ≥208. Patients with HPR before TAVR were randomized to either aspirin + ticagrelor or aspirin + clopidogrel for 3 months. Patients without HPR continued with aspirin + clopidogrel (registry cohort). The primary endpoint was non-HPR status (PRU <208) in ≥70% of patients treated with ticagrelor at 90 days post-TAVR.Results
A total of 68 patients were included. Of these, 48 (71%) had HPR (PRU 273 ± 09) and were randomized to aspirin + ticagrelor (n = 24, PRU 277 ± 08) or continued with aspirin + clopidogrel (n = 24, PRU 269 ± 49). The remaining 20 patients (29%) without HPR (PRU 133 ± 12) were included in the registry. Overall, platelet reactivity across all the study time points after TAVR was lower in patients randomized to ticagrelor compared with those treated with clopidogrel, including those enrolled in the registry (p < 0.001). The primary endpoint was achieved in 100% of patients with ticagrelor compared with 21% with clopidogrel (p < 0.001). Interestingly, 33% of clopidogrel responder patients at baseline developed HPR status during the first month after TAVR.Conclusions
HPR to clopidogrel is present in a considerable number of patients with AS undergoing TAVR. Ticagrelor achieves a better and faster effect, providing sustained suppression of HPR to these patients. (Platelet Reactivity After TAVI: A Multicenter Pilot Study [REAC-TAVI]; NCT02224066) 相似文献54.
Amparo Aloy-Prósper David Pe?arrocha-Oltra Maria A. Pe?arrocha-Diago Miguel Pe?arrocha-Diago 《Medicina oral, patología oral y cirugía bucal》2015,20(2):e251-e258
Aim: The purpose of this study was to systematically review clinical studies examining the survival and success rates of implants placed with intraoral onlay autogenous bone grafts to answer the following question: do ridge augmentations procedures with intraoral onlay block bone grafts in conjunction with or prior to implant placement influence implant outcome when compared with a control group (guided bone regeneration, alveolar distraction, native bone or short dental implants.)?
Material and Method: An electronic data banks and hand searching were used to find relevant articles on vertical and lateral augmentation procedures performed with intraoral onlay block bone grafts for dental implant therapy published up to October 2013. Publications in English, on human subjects, with a controlled study design –involving at least one group with defects treated with intraoral onlay block bone grafts, more than five patients and a minimum follow-up of 12 months after prosthetic loading were included. Two reviewers extracted the data.
Results: A total of 6 studies met the inclusion criteria: 4 studies on horizontal augmentation and 2 studies on vertical augmentation. Intraoperative complications were not reported. Most common postsurgical complications included mainly mucosal dehiscences (4 studies), bone graft or membrane exposures (3 studies), complete failures of block grafts (2 studies) and neurosensory alterations (4 studies). For lateral augmentation procedures, implant survival rates ranged from 96.9% to 100%, while for vertical augmentation they ranged from 89.5% to 100%. None article studied the soft tissues healing.
Conclusions: Survival and success rates of implants placed in horizontally and vertically resorbed edentulous ridges reconstructed with block bone grafts are similar to those of implants placed in native bone, in distracted sites or with guided bone regeneration. More surgical challenges and morbidity arise from vertical augmentations, thus short implants may be a feasible option.
Key words:Alveolar ridge augmentation, intraoral bone grafts, onlay grafts, block grafts, dental implants. 相似文献
55.
Angela M. C. Rose Esther Kissling Alin Gherasim Itziar Casado Antonino Bella Odile Launay Mihaela Lazr Sierk Marbus Monika Kuliese Ritva Syrjnen Ausenda Machado Sanja Kure
i Filipovi Amparo Larrauri Jesús Castilla Valeria Alfonsi Florence Galtier Alina Ivanciuc Adam Meijer Aukse Mickiene Niina Ikonen Vernica Gmez Zvjezdana Lovri Makari Alain Moren Marta Valenciano 《Influenza and other respiratory viruses》2020,14(3):302-310
56.
Amparo de la Pe?a Xiaosu Ma Shobha Reddy Fernando Ovalle Richard M. Bergenstal Jeffrey A. Jackson 《Journal of diabetes science and technology》2014,8(4):821-829
Background:Pharmacokinetic/pharmacodynamic (PK/PD) studies of human regular U-500 insulin (U-500R) at high doses commonly used in clinical practice (>100 units) have not been performed. The current analysis applied PK/PD modeling/simulation to fit the data and simulate single-dose and steady-state PK/PD of U-500R high-dose regimens.Method:Data from 3 single-dose euglycemic clamp studies in healthy obese and normal-weight patients, and normal-weight patients with type 1 diabetes were used to build the model. The model was sequential (PK inputs fed into PD component). PK was described using a 1-compartment model with first-order absorption and elimination. The model estimated separate absorption rate constants for U-500R and human regular U-100 insulin. The PD component used an effect compartment model, parameterized in terms of maximum pharmacologic effect (Emax) and concentration to achieve 50% of Emax.Results:The model described the data well. Steady-state PK for once-daily (QD), twice-daily (BID), or thrice-daily (TID) administration appeared to be reached 24 hours after the first dose. At steady-state, QD dosing showed the greatest fluctuations in PK/PD. BID dosing showed a gradual increase in insulin action with each dose and a fairly stable basal insulin effect. For TID dosing, activity was maintained throughout the dosing interval.Conclusions:PK/PD modeling/simulation of high U-500R doses supports BID or TID administration with an extended duration of activity relative to QD. TID dosing may provide slightly better full-day insulin effect. Additional PK/PD studies and randomized controlled trials of U-500R are needed to validate model predictions in patients with insulin-resistant diabetes requiring high-dose insulin. 相似文献
57.
Helena M. de Wit Gerald M. M. Vervoort Henry J. Jansen Wim J. C. de Grauw Bastiaan E. de Galan Cees J. Tack 《Diabetologia》2014,57(9):1812-1819
Aims/hypothesis
The best treatment strategy for a patient with type 2 diabetes who shows pronounced weight gain after the introduction of insulin treatment is unclear. We determined whether addition of a glucagon-like peptide-1 (GLP-1) analogue could reverse pronounced insulin-associated weight gain while maintaining glycaemic control, and compared this with the most practised strategy, continuation and intensification of standard insulin therapy.Methods
In a 26-week, randomised controlled trial (ELEGANT), conducted in the outpatient departments of one academic and one large non-academic teaching hospital in the Netherlands, adult patients with type 2 diabetes with ≥4% weight gain during short-term (≤16 months) insulin therapy received either open-label addition of liraglutide 1.8 mg/day (n?=?26) or continued standard therapy (n?=?24). A computer-generated random number list was used to allocate treatments. Participants were evaluated every 4–6 weeks for weight, glycaemic control and adverse events. The primary endpoint was between-group weight difference after 26 weeks of treatment (intention to treat).Results
Of 50 randomised patients (mean age 58 years, BMI 33 kg/m2, HbA1c 7.4% [57 mmol/mol]), 47 (94%) completed the study; all patients were analysed. Body weight decreased by 4.5 kg with liraglutide and increased by 0.9 kg with standard therapy (mean difference ?5.2 kg [95% CI ?6.7, ?3.6 kg]; p?0.001). The respective changes in HbA1c were ?0.77% (?8.4 mmol/mol) and +0.01% (+0.1 mmol/mol) (difference ?0.74% [?8.1 mmol/mol]) ([95% CI ?1.08%, ?0.41%] [?11.8, ?4.5 mmol/mol]; p?0.001); respective changes in insulin dose were ?29 U/day and +5 U/day (difference ?33 U/day [95% CI ?41, ?25 U/day]; p?0.001). In five patients (19%), insulin could be completely discontinued. Liraglutide was well tolerated; no severe adverse events or severe hypoglycaemia occurred.Conclusions/interpretation
In patients with pronounced insulin-associated weight gain, addition of liraglutide to their treatment regimen reverses weight, decreases insulin dose and improves glycaemic control, and hence seems a valuable therapeutic option compared with continuation of standard insulin treatment. Trial registration ClinicalTrials.gov NCT01392898 Funding The study was funded by Novo Nordisk. 相似文献58.
59.
Zoungas S Chalmers J Ninomiya T Li Q Cooper ME Colagiuri S Fulcher G de Galan BE Harrap S Hamet P Heller S MacMahon S Marre M Poulter N Travert F Patel A Neal B Woodward M;ADVANCE Collaborative Group 《Diabetologia》2012,55(3):636-643
Aims/hypothesis
There is conflicting evidence regarding appropriate glycaemic targets for patients with type 2 diabetes. Here, we investigate the relationship between HbA1c and the risks of vascular complications and death in such patients.Methods
Eleven thousand one hundred and forty patients were randomised to intensive or standard glucose control in the Action in Diabetes and Vascular disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) trial. Glycaemic exposure was assessed as the mean of HbA1c measurements during follow-up and prior to the first event. Adjusted risks for each HbA1c decile were estimated using Cox models. Possible differences in the association between HbA1c and risks at different levels of HbA1c were explored using linear spline models.Results
There was a non-linear relationship between mean HbA1c during follow-up and the risks of macrovascular events, microvascular events and death. Within the range of HbA1c studied (5.5?C10.5%), there was evidence of ??thresholds??, such that below HbA1c levels of 7.0% for macrovascular events and death, and 6.5% for microvascular events, there was no significant change in risks (all p?>?0.8). Above these thresholds, the risks increased significantly: every 1% higher HbA1c level was associated with a 38% higher risk of a macrovascular event, a 40% higher risk of a microvascular event and a 38% higher risk of death (all p?0.0001).Conclusions/interpretation
In patients with type 2 diabetes, HbA1c levels were associated with lower risks of macrovascular events and death down to a threshold of 7.0% and microvascular events down to a threshold of 6.5%. There was no evidence of lower risks below these levels but neither was there clear evidence of harm.Trial Registration:
ClinicalTrial.gov NCT00145925Funding:
Servier and the National Health and Medical Research Council of Australia (project grant ID 211086 and programme grant IDs 358395 and 571281) 相似文献60.
Ruiz A Liu Y Xu X Carlson M 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(22):8652-8657
The SNF1/AMP-activated protein kinases are αβγ-heterotrimers that sense and regulate energy status in eukaryotes. They are activated by phosphorylation of the catalytic Snf1/α subunit, and the Snf4/γ regulatory subunit regulates phosphorylation through adenine nucleotide binding. In Saccharomyces cerevisiae, the Snf1 subunit is phosphorylated on the activation-loop Thr-210 in response to glucose limitation. To assess the requirement of the heterotrimer for regulated Thr-210 phosphorylation, we examined Snf1 and a truncated Snf1 kinase domain (residues 1-309) that has partial Snf1 function. Snf1(1-309) does not interact with the β and Snf4/γ regulatory subunits, and its activity was independent of them in vivo. Phosphorylation of both Snf1 and Snf1(1-309) increased in response to glucose limitation in wild-type cells and in cells lacking β- and Snf4/γ-subunits. These results indicate that glucose regulation of activation-loop phosphorylation can occur by mechanism(s) that function independently of the regulatory subunits. We further show that the Reg1-Glc7 protein phosphatase 1 and Sit4 type 2A-like phosphatase are largely responsible for dephosphorylation of Thr-210 of Snf1(1-309). Together, these findings suggest that these two phosphatases mediate heterotrimer-independent regulation of Thr-210 phosphorylation. 相似文献