523 research outputs found
Changing clinical and therapeutic trends in tentorial dural arteriovenous fistulas: a systematic review
BACKGROUND AND PURPOSE: Tentorial dural arteriovenous fistulas are characterized by a high hemorrhagic risk. We evaluated trends in outcomes and management of tentorial dural arteriovenous fistulas and performed a meta-analysis evaluating clinical and angiographic outcomes by treatment technique. MATERIALS AND METHODS: We performed a comprehensive literature search for studies on surgical and endovascular treatment of tentorial dural arteriovenous fistulas. We compared the proportion of patients undergoing endovascular, surgical, and combined endovascular/surgical management; the proportion of patients presenting with ruptured tentorial dural arteriovenous fistulas; and proportion of patients with good neurologic outcome across 3 time periods: 1980-1995, 1996-2005, and 2006-2014. We performed a random-effects meta-analysis, evaluating the rates of occlusion, long-term good neurologic outcome, perioperative morbidity, and resolution of symptoms for the 3 treatment modalities. RESULTS: Twenty-nine studies with 274 patients were included. The proportion of patients treated with surgical treatment alone decreased from 38.7% to 20.4% between 1980-1995 and 2006-2014. The proportion of patients treated with endovascular therapy alone increased from 16.1% to 48.0%. The proportion of patients presenting with ruptured tentorial dural arteriovenous fistulas decreased from 64.4% to 43.6%. The rate of good neurologic outcome increased from 80.7% to 92.9%. Complete occlusion rates were highest for patients receiving multimodality treatment (84.0%; 95% CI, 72.0%-91.0%) and lowest for endovascular treatment (71.0%; 95% CI, 56.0%-83.0%; P < .01). Long-term good neurologic outcome was highest in the endovascular group (89.0%; 95% CI, 80.0%-95.0%) and lowest for the surgical group (73.0%; 95% CI, 51.0%-87.0%; P < .03). CONCLUSIONS: Patients with tentorial dural arteriovenous fistulas are increasingly presenting with unruptured lesions, being treated endovascularly, and experiencing higher rates of good neurologic outcomes. Endovascular treatment was associated with superior neurologic outcomes but lower occlusion rate
FoxO3a as a positive prognostic marker and a therapeutic target in Tamoxifen-resistant breast cancer
Background: Resistance to endocrine treatments is a major clinical challenge in the management of estrogen receptor positive breast cancers. Although multiple mechanisms leading to endocrine resistance have been proposed, the poor outcome of this subgroup of patients demands additional studies. Methods: FoxO3a involvement in the acquisition and reversion of tamoxifen resistance was assessed in vitro in three parental ER+ breast cancer cells, MCF-7, T47D and ZR-75-1, in the deriving Tamoxifen resistant models (TamR) and in Tet-inducible TamR/FoxO3a stable cell lines, by growth curves, PLA, siRNA, RT-PCR, Western blot, Immunofluorescence, Transmission Electron Microscopy, TUNEL, cell cycle, proteomics analyses and animal models. FoxO3a clinical relevance was validated in silico by Kaplan−Meier survival curves. Results: Here, we show that tamoxifen resistant breast cancer cells (TamR) express low FoxO3a levels. The hyperactive growth factors signaling, characterizing these cells, leads to FoxO3a hyper-phosphorylation and subsequent proteasomal degradation. FoxO3a re-expression by using TamR tetracycline inducible cells or by treating TamR with the anticonvulsant lamotrigine (LTG), restored the sensitivity to the antiestrogen and strongly reduced tumor mass in TamR-derived mouse xenografts. Proteomics data unveiled novel potential mediators of FoxO3a anti-proliferative and pro-apoptotic activity, while the Kaplan−Meier analysis showed that FoxO3a is predictive of a positive response to tamoxifen therapy in Luminal A breast cancer patients. Conclusions: Altogether, our data indicate that FoxO3a is a key target to be exploited in endocrine-resistant tumors. In this context, LTG, being able to induce FoxO3a, might represent a valid candidate in combination therapy to prevent resistance to tamoxifen in patients at risk
A Novel Transformer-Based IMU Self-Calibration Approach through On-Board RGB Camera for UAV Flight Stabilization
During flight, unmanned aerial vehicles (UAVs) need several sensors to follow a predefined path and reach a specific destination. To this aim, they generally exploit an inertial measurement unit (IMU) for pose estimation. Usually, in the UAV context, an IMU entails a three-axis accelerometer and a three-axis gyroscope. However, as happens for many physical devices, they can present some misalignment between the real value and the registered one. These systematic or occasional errors can derive from different sources and could be related to the sensor itself or to external noise due to the place where it is located. Hardware calibration requires special equipment, which is not always available. In any case, even if possible, it can be used to solve the physical problem and sometimes requires removing the sensor from its location, which is not always feasible. At the same time, solving the problem of external noise usually requires software procedures. Moreover, as reported in the literature, even two IMUs from the same brand and the same production chain could produce different measurements under identical conditions. This paper proposes a soft calibration procedure to reduce the misalignment created by systematic errors and noise based on the grayscale or RGB camera built-in on the drone. Based on the transformer neural network architecture trained in a supervised learning fashion on pairs of short videos shot by the UAV’s camera and the correspondent UAV measurements, the strategy does not require any special equipment. It is easily reproducible and could be used to increase the trajectory accuracy of the UAV during the flight
The unruptured intracranial aneurysm treatment score A multidisciplinary consensus
Objective: We endeavored to develop an unruptured intracranial aneurysm (UIA) treatment score (UIATS) model that includes and quantifies key factors involved in clinical decision-making in the management of UIAs and to assess agreement for this model among specialists in UIA management and research. Methods: An international multidisciplinary (neurosurgery, neuroradiology, neurology, clinical epidemiology) group of 69 specialists was convened to develop and validate the UIATS model using a Delphi consensus. For internal (39 panel members involved in identification of relevant features) and external validation (30 independent external reviewers), 30 selected UIA cases were used to analyze agreement with UIATS management recommendations based on a 5-point Likert scale (5 indicating strong agreement). Interrater agreement (IRA) was assessed with standardized coefficients of dispersion (v(r)*) (v(r)* 5 0 indicating excellent agreement and v(r)* = 1 indicating poor agreement). Results: The UIATS accounts for 29 key factors in UIA management. Agreement with UIATS (mean Likert scores) was 4.2 (95% confidence interval [CI] 4.1-4.3) per reviewer for both reviewer cohorts; agreement per case was 4.3 (95% CI 4.1-4.4) for panel members and 4.5 (95% CI 4.3-4.6) for external reviewers (p = 0.017). Mean Likert scores were 4.2 (95% CI 4.1-4.3) for interventional reviewers (n = 56) and 4.1 (95% CI 3.9-4.4) for noninterventional reviewers (n = 12) (p = 0.290). Overall IRA (v(r)*) for both cohorts was 0.026 (95% CI 0.019-0.033). Conclusions: This novel UIA decision guidance study captures an excellent consensus among highly informed individuals on UIA management, irrespective of their underlying specialty. Clinicians can use the UIATS as a comprehensive mechanism for indicating how a large group of specialists might manage an individual patient with a UIA.Peer reviewe
The restoring of interhemispheric brain connectivity following carotid endarterectomy: an exploratory observational study
This study aimed to evaluate the differences of brain connectivity between healthy subjects (HS) and patients with extracranial internal carotid artery (eICA) stenosis before and after carotid endarterectomy (CEA). An exploratory prospective study was designed. The study population consisted of a patient group (PG) of 20 patients with eICA stenosis eligible for CEA, and a control group (CG) of 20 HS, matched for age and sex. The subjects of the PG group underwent Magnetic Resonance Imaging (MRI) for resting-state functional connectivity MRI (rs-fc MRI) analysis within one week from the CEA (pre-CEA) and 12 months following CEA (post-CEA). The CG underwent a single MRI with the same protocol utilized for the PG. Three region-of-interest to region-of-interest (ROI-to-ROI) rs-fc MRI analyses were conducted: analysis 1 to compare pre-CEA PG and CG; analysis 2 to compare pre-CEA PG and post-CEA PG; analysis 3 to compare post-CEA PG and CG. The Functional Network Connectivity multivariate parametric technique was used for statistical analysis, adopting a p-uncorrected (p-unc) < 0.05 as connection threshold, and a cluster level False Discovery Rate corrected p (p-FDR) < 0.05 as cluster threshold. The clusters were defined by using a data-driven hierarchical clustering procedure. Analysis 1 revealed two clusters of reduced interhemispheric connectivity of pre-CEA PG when compared to CG. Analysis 2 and 3 showed no statistically significant differences. Our exploratory analysis suggests that patients with eICA stenosis have reduced interhemispheric connectivity when compared to a matched control group, and this difference was not evident anymore following endarterectomy
The estrogen receptor alpha:insulin receptor substrate 1 complex in breast cancer: structure-function relationships
Background: Insulin receptor substrate 1 (IRS-1) is a signaling molecule that exerts a key role in mediating cross talk
between estrogen receptor a (ERa) and insulin-like growth factor 1 (IGF-1) in breast cancer cells. Previously, we
demonstrated that a fraction of IRS-1 binds ERa, translocates to the nucleus, and modulates ERa-dependent
transcription at estrogen response elements (ERE). Here, we studied structure–function relationships of the ERa:IRS-1
complex under IGF-1 and/or estradiol (E2) stimulation.
Materials and methods: ERa and IRS-1 deletion mutants were used to analyze structural and functional ERa/IRS-1
interactions. IRS-1 binding to ERE and IRS-1 role in ERa-dependent ERE transcription was examined by chromatin
immunoprecipitation and gene reporter analysis, respectively. The requirement for IRS-1 in ERa function was tested
with RNAi technology.
Results: Nuclear translocation of IRS-1 was induced by E2, IGF-1, and a combination of both stimuli. ERa/IRS-1
binding was direct and involved the activation function-1 (AF-1)/DNA binding domain (DBD) region of ERa and two
discrete regions of IRS-1 (the N-terminal pleckstrin homology domain and a region within the C-terminus). IRS-1 knock
down abrogated IGF-1-dependent transcriptional activity of unliganded ERa, but induced the activity of liganded ERa.
Conclusions: ERa/IRS-1 interactions are direct and involve the ERa AF-1/DBD domain and IRS-1 domains mapping
within N- and C-terminus. IRS-1 may act as a repressor of liganded ERa and coactivator of unliganded ERa
A Novel GAN-Based Anomaly Detection and Localization Method for Aerial Video Surveillance at Low Altitude
The last two decades have seen an incessant growth in the use of Unmanned Aerial Vehicles (UAVs) equipped with HD cameras for developing aerial vision-based systems to support civilian and military tasks, including land monitoring, change detection, and object classification. To perform most of these tasks, the artificial intelligence algorithms usually need to know, a priori, what to look for, identify. or recognize. Actually, in most operational scenarios, such as war zones or post-disaster situations, areas and objects of interest are not decidable a priori since their shape and visual features may have been altered by events or even intentionally disguised (e.g., improvised explosive devices (IEDs)). For these reasons, in recent years, more and more research groups are investigating the design of original anomaly detection methods, which, in short, are focused on detecting samples that differ from the others in terms of visual appearance and occurrences with respect to a given environment. In this paper, we present a novel two-branch Generative Adversarial Network (GAN)-based method for low-altitude RGB aerial video surveillance to detect and localize anomalies. We have chosen to focus on the low-altitude sequences as we are interested in complex operational scenarios where even a small object or device can represent a reason for danger or attention. The proposed model was tested on the UAV Mosaicking and Change Detection (UMCD) dataset, a one-of-a-kind collection of challenging videos whose sequences were acquired between 6 and 15 m above sea level on three types of ground (i.e., urban, dirt, and countryside). Results demonstrated the effectiveness of the model in terms of Area Under the Receiving Operating Curve (AUROC) and Structural Similarity Index (SSIM), achieving an average of 97.2% and 95.7%, respectively, thus suggesting that the system can be deployed in real-world applications
Tailored management of cavernous malformations in women: considerations and strategies—a review
Purpose of reviewCavernous malformations (CM) are vascular lesions in the brain and spinal cord, characterized by clusters of endothelial-lined caverns lacking proper tight junctions. These malformations may be discovered incidentally or present with symptoms such as headaches, focal neurologic deficits, or seizures, with or without hemorrhage. This review focuses on non-surgical management considerations important for women with CM, who face challenges related to pregnancy, exogenous hormone use, anticonvulsive therapy, bone health, and mental health.Recent findingsEmerging evidence suggests that both estrogen and progesterone may influence CM lesion behavior. Exogenous hormones, including those in oral contraceptives and oral hormone replacement therapy, indicate an elevated risk of symptomatic hemorrhage (SH) and may also influence seizure frequency and severity, particularly in women taking antiseizure medications (ASMs). Data suggest that the risk of CM hemorrhage during pregnancy is similar to the risk when not pregnant, although limitations to these studies will be reviewed.SummaryThis review synthesizes the current literature on the interplay between estrogen and progesterone and CM lesion behavior, highlighting the importance of gender- and sex-specific factors in clinical decision-making. Special attention is given to the implications of exogenous hormone use, seizure management, and the psychological well-being of women with CM, underscoring the need for a multidisciplinary approach tailored to the unique needs of this patient population
Surgical clipping is still a good choice for the treatment of paraclinoid aneurysms
ABSTRACT Paraclinoid aneurysms are lesions located adjacent to the clinoid and ophthalmic segments of the internal carotid artery. In recent years, flow diverter stents have been introduced as a better endovascular technique for treatment of these aneurysms. Method From 2009 to 2014, a total of 43 paraclinoid aneurysms in 43 patients were surgically clipped. We retrospectively reviewed the records of these patients to analyze clinical outcomes. Results Twenty-six aneurysms (60.5%) were ophthalmic artery aneurysms, while 17 were superior hypophyseal artery aneurysms (39.5%). The extradural approach to the clinoid process was used to clip these aneurysms. One hundred percent of aneurysms were clipped (complete exclusion in 100% on follow-up angiography). The length of follow-up ranged from 1 to 60 months (mean, 29.82 months). Conclusion Surgical clipping continues to be a good option for the treatment of paraclinoid aneurysms
Natural course of subarachnoid hemorrhage is worse in elderly patients
Aging is a major risk factor for poor outcome in patients with ruptured or unruptured intracranial aneurysms (IA) submitted to treatment. It impairs several physiologic patterns related to cerebrovascular hemodynamics and homeostasis. Objective Evaluate clinical, radiological patterns and prognostic factors of subarachnoid hemorrhage (SAH) patients according to age. Method Three hundred and eighty nine patients with aneurismal SAH from a Brazilian tertiary institution (Hospital do Servidor Público Estadual de São Paulo) were consecutively evaluated from 2002 to 2012 according to Fisher and Hunt Hess classifications and Glasgow Outcome Scale. Results There was statistically significant association of age with impaired clinical, radiological presentation and outcomes in cases of SAH. Conclusion Natural course of SAH is worse in elderly patients and thus, proper recognition of the profile of such patients and their outcome is necessary to propose standard treatment
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