Noninvasive brain stimulation has been demonstrated to modulate cortical activity in humans. In particular, theta burst stimulation (TBS) has gained notable attention due to its ability to induce ...lasting physiological changes after short stimulation durations. The present study aimed to provide a comprehensive meta-analytic review of the efficacy of two TBS paradigms; intermittent (iTBS) and continuous (cTBS), on corticospinal excitability in healthy individuals. Literature searches yielded a total of 87 studies adhering to the inclusion criteria. iTBS yielded moderately large MEP increases lasting up to 30 min with a pooled SMD of 0.71 (p<0.00001). cTBS produced a reduction in MEP amplitudes lasting up to 60 min, with the largest effect size seen at 5 min post stimulation (SMD=-0.9, P<0.00001). The collected studies were of heterogeneous nature, and a series of tests conducted indicated a degree of publication bias. No significant change in SICI and ICF was observed, with exception to decrease in SICI with cTBS at the early time point (SMD=0.42, P=0.00036). The results also highlight several factors contributing to TBS efficacy, including the number of pulses, frequency of stimulation and BDNF polymorphisms. Further research investigating optimal TBS stimulation parameters, particularly for iTBS, is needed in order for these paradigms to be successfully translated into clinical settings.
Two trials enrolled a total of 2701 patients who had undergone implantation of a drug-eluting coronary stent and had been receiving dual antiplatelet therapy for at least 12 months. They were ...randomly assigned to either continuation or discontinuation of clopidogrel therapy. At 19.2 months after randomization, the rate of myocardial infarction or death from cardiac causes did not differ significantly between the two groups.
Patients who had undergone implantation of a drug-eluting coronary stent and had been receiving dual antiplatelet therapy for at least 12 months were randomly assigned to either continuation or discontinuation of clopidogrel therapy. At 19.2 months after randomization, the rate of myocardial infarction or death from cardiac causes did not differ significantly between the two groups.
Several pivotal clinical trials have shown that the use of drug-eluting coronary stents is associated with significant reductions in the risks of restenosis and need for target-lesion revascularization, as compared with use of bare-metal coronary stents.
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On the basis of the results of these trials, drug-eluting stents have been widely used for percutaneous coronary intervention (PCI) in clinical practice.
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However, some longer-term studies have shown that drug-eluting stents, as compared with bare-metal stents, are associated with increased rates of late stent thrombosis, death, or myocardial infarction.
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It has been proposed that the occurrence of late clinical events may be . . .
Self-Assembly of Mesoscopic Metal-Polymer Amphiphiles Park, Sungho; Lim, Jung-Hyurk; Chung, Sung-Wook ...
Science (American Association for the Advancement of Science),
01/2004, Letnik:
303, Številka:
5656
Journal Article
Recenzirano
The assembly properties of two- and three-component rod-like building blocks consisting of gold and polymer block domains have been investigated. These structures behave like mesoscopic amphiphiles ...and form a series of single-layer superstructures consisting of bundles, tubes, and sheets depending upon the compositional periodicity. Unlike molecular systems, the template used to initially synthesize them plays a critical role in the assembly process by prealigning them in a manner that facilitates their assembly by optimizing the correct collisional orientation upon dissolution of the template. Tubular structures with tailorable diameters can be assembled in a predictable manner on the basis of an estimate of the hybrid rod packing parameters.
A cohort of patients who underwent stent implantation for unprotected left main coronary artery disease was compared with a propensity-matched cohort of patients who underwent coronary-artery bypass ...grafting. The risk of death and the composite outcome of death, Q-wave myocardial infarction, or stroke did not differ significantly between the two groups. The risk of target-vessel revascularization was higher in the group that received stents.
The risk of death and the composite outcome of death, Q-wave myocardial infarction, or stroke did not differ significantly between the two groups. The risk of target-vessel revascularization was higher in the group that received stents.
Significant narrowing of the left main coronary artery puts a patient at high risk, since it can jeopardize the entire myocardium of the left ventricle, and it has the worst prognosis of any form of coronary artery disease.
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On the basis of clinical trials that show a survival benefit with bypass surgery as compared with medical treatment,
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coronary-artery bypass grafting (CABG) has been considered standard therapy for patients with left main coronary artery disease and is recommended by current practice guidelines.
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Because of concern about procedural risk and long-term durability, percutaneous coronary intervention (PCI) usually has been restricted . . .
Phase-change materials undergo rapid and reversible crystalline-to-amorphous structural transformation and are being used for nonvolatile memory devices. However, the transformation mechanism remains ...poorly understood. We have studied the effect of electrical pulses on the crystalline-to-amorphous phase change in a single-crystalline Ge₂Sb₂Te₂ (GST) nanowire memory device by in situ transmission electron microscopy. We show that electrical pulses produce dislocations in crystalline GST, which become mobile and glide in the direction of hole-carrier motion. The continuous increase in the density of dislocations moving unidirectionally in the material leads to dislocation jamming, which eventually induces the crystalline-to-amorphous phase change with a sharp interface spanning the entire nanowire cross section. The dislocation-templated amorphization explains the large on/off resistance ratio of the device.
The high capacity of the layered Li–excess oxide cathode is always accompanied by extraction of a significant amount of oxygen from the structure. The effects of oxygen on the electrochemical cycling ...are not well understood. Here, the detailed reaction scheme following oxygen evolution was established using real-time gas analysis and ex situ chemical analysis of the surface of the electrodes. A series of electrochemical/chemical reactions involving oxygen radicals constantly produced and decomposed lithium carbonate during cell operation. Moreover, byproducts, including water, affected the cycle life and rate capability: hydrolysis of the electrolyte salt formed hydrofluoric acid that attacked the surface of the electrode. This finding implies that protection of the electrode surface from damage, for example, by a coating or removal of oxygen radicals by scavengers, will be critical to widespread usage of Li–excess transition metal oxides in rechargeable lithium batteries.
Early detection and classification of bone tumors in the proximal femur is crucial for their successful treatment. This study aimed to develop an artificial intelligence (AI) model to classify bone ...tumors in the proximal femur on plain radiographs.
Standard anteroposterior hip radiographs were obtained from a single tertiary referral center. A total of 538 femoral images were set for the AI model training, including 94 with malignant, 120 with benign, and 324 without tumors. The image data were pre-processed to be optimized for training of the deep learning model. The state-of-the-art convolutional neural network (CNN) algorithms were applied to pre-processed images to perform three-label classification (benign, malignant, or no tumor) on each femur. The performance of the CNN model was verified using fivefold cross-validation and was compared against that of four human doctors.
The area under the receiver operating characteristic (AUROC) of the best performing CNN model for the three-label classification was 0.953 (95% confidence interval, 0.926-0.980). The diagnostic accuracy of the model (0.853) was significantly higher than that of the four doctors (0.794) (P = 0.001) and also that of each doctor individually (0.811, 0.796, 0.757, and 0.814, respectively) (P<0.05). The mean sensitivity, specificity, precision, and F1 score of the CNN models were 0.822, 0.912, 0.829, and 0.822, respectively, whereas the mean values of four doctors were 0.751, 0.889, 0.762, and 0.797, respectively.
The AI-based model demonstrated high performance in classifying the presence of bone tumors in the proximal femur on plain radiographs. Our findings suggest that AI-based technology can potentially reduce the misdiagnosis of doctors who are not specialists in musculoskeletal oncology.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background:Although there is an increase in the use of mechanical circulatory support devices to rescue patients with acute myocardial infarction (AMI) complicated by refractory cardiogenic shock ...(CS), the optimal timing of the application remains controversial. Therefore, this study aimed to compare the clinical outcomes between venoarterial-extracorporeal membrane oxygenation (VA-ECMO) insertion before and after coronary revascularization in AMI patients with refractory CS.Methods and Results:A total of 253 patients with AMI who underwent revascularization therapy with VA-ECMO were included. The study population was stratified into extracorporeal cardiopulmonary resuscitation (E-CPR) before revascularization (N=106, reference cohort) and refractory CS without E-CPR before revascularization (n=147, comparison cohort). Patients with refractory CS but without E-CPR before revascularization were further divided into VA-ECMO before revascularization (N=50) and VA-ECMO after revascularization (n=97). The primary endpoint was a composite of in-hospital mortality, left ventricular assist device implantation, and heart transplantation. The primary endpoint occurred in 60 patients (40.8%) of the comparison cohort and 51 patients (48.1%) of the reference cohort. Among the comparison cohort, the primary endpoint was significantly lower in VA-ECMO before revascularization than in VA-ECMO after revascularization (32.0% vs. 49.5%, OR 0.480, 95% CI 0.235–0.982, P=0.045). A similar trend was observed after a 1-year follow up.Conclusions:Early initiation of VA-ECMO before revascularization therapy might improve clinical outcomes in patients with AMI complicated by refractory CS.
Intimate electrical contact occurs between a substituted poly(metaphenylenevinylene) (PmPV) and bundles of single‐walled nanotubes (SWNT) as evidenced by atomic force microscopy, optical, and ...electronic measurements carried out on single, isolated SWNT/PmPV structures (see picture). PmPV may provide a useful route toward “functionalizing” the SWNT without destroying their electrical character.
Pericyte loss is an early characteristic change in diabetic retinopathy (DR). Despite accumulating evidence that hyperglycemia-induced angiopoietin 2 (Ang2) has a central role in pericyte loss, the ...precise molecular mechanism has not been elucidated. This study investigated the role of Ang2 in pericyte loss in DR. We demonstrated that pericyte loss occurred with Ang2 increase in the diabetic mouse retina and that the source of Ang2 could be the endothelial cell. Ang2 induced pericyte apoptosis via the p53 pathway under high glucose, whereas Ang2 alone did not induce apoptosis. Integrin, not Tie-2 receptor, was involved for Ang2-induced pericyte apoptosis under high glucose as an Ang2 receptor. High glucose changed the integrin expression pattern, which increased integrin α3 and β1 in the pericyte. Furthermore, Ang2-induced pericyte apoptosis in vitro was effectively attenuated via p53 suppression by blocking integrin α3 and β1. Although intravitreal injection of Ang2 induced pericyte loss in C57BL/6J mice retina in vivo, intravitreal injection of anti-integrin α3 and β1 antibodies attenuated Ang2-induced pericyte loss. Taken together, Ang2 induced pericyte apoptosis under high glucose via α3β1 integrin. Glycemic control or blocking Ang2/integrin signaling could be a potential therapeutic target to prevent pericyte loss in early DR.
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