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1.

Purpose

To compare automated measurements of maximal diameter (Dmax) of abdominal aortic aneurysm (AAA) orthogonal to luminal or outer wall envelope centerline for endovascular repair (EVAR) follow-up.

Material and Methods

Eighty-three consecutive patients with AAA treated by EVAR who had at least 1 computed tomography (CT) scan before and 2 CT scans after EVAR with at least 5 months’ interval were included. Three-dimensional reconstruction of the AAA was achieved with dedicated segmentation software. Performances of automated calculation algorithms of Dmax perpendicular to lumen or outer wall envelope centerlines were then compared to manual measurement of Dmax on double-oblique multiplanar reconstruction (gold standard). Accuracy of automated Dmax measurements at baseline, follow-up, and progression over time was evaluated by calculation of mean error, Bland-Altman plot, and regression models.

Results

Disagreement in Dmax measurements between outer wall envelope algorithm and manual method was insignificant (mean error: baseline, -0.07 ± 1.66 mm, P = .7; first follow-up, 0.24 ± 1.69 mm, P = .2; last follow-up, -0.41 ± 2.74 mm, P = .17); whereas significant discrepancies were found between the luminal algorithm and the manual method (mean error: baseline, -1.24 ± 2.01 mm, P < .01; first follow-up, -1.49 ± 3.30 mm, P < .01; last follow-up, -1.78 ± 3.60 mm, P < .01). Dmax progression results were more accurate with AAA outer wall envelope algorithm compared to luminal method (P = .2).

Conclusions

AAA outer wall envelope segmentation is recommended to enable automated calculation of Dmax perpendicular to its centerline during EVAR follow-up.  相似文献   
2.
3.
Introduction: Inflammatory bowel diseases, such as Crohn’s disease (CD) and ulcerative colitis (UC), are widespread diseases (with an estimated 2.2 million Europeans affected), and even populations previously considered ‘low risk’ (such as Japan and India) are witnessing an increasing incidence. CD is a chronic, progressive immunologically driven disease, with an evolution characterized by succession of periods of progression and remission. New physiopathological pathways are continuously being discovered, the more we understand about how the disease appears and progresses, the more targets become available for the development of novel therapies.

Areas covered: Filgotinib is one of these promising new therapies; this article discusses the currently available data. We used an exhaustive search of the PubMed database to corroborate information regarding its chemical characteristics, and the studies evaluating clinical efficacy and safety.

Expert opinion: Up to now, the phase-II study evaluating Filgotinib yielded very promising results in moderate to severe CD patients, with good clinical response, mucosal healing, while having few and moderate adverse effects, both in anti-TNF naïve and resistant patients. Phase-III studies are still ongoing and will help decide whether Filgotinib will be a worthwhile drug in the treatment of CD and the best way to use it.  相似文献   

4.
Cerebral adrenoleukodystrophy (CALD) is a rapidly progressing, often fatal neurodegenerative disease caused by mutations in the ABCD1 gene, resulting in deficiency of ALD protein. Clinical benefit has been reported following allogeneic hematopoietic stem cell transplantation (HSCT). We conducted a large multicenter retrospective chart review to characterize the natural history of CALD, to describe outcomes after HSCT, and to identify predictors of treatment outcomes. Major functional disabilities (MFDs) were identified as having the most significant impact on patients’ abilities to function independently and were used to assess HSCT outcome. Neurologic function score (NFS) and Loes magnetic resonance imaging score were assessed. Data were collected on 72 patients with CALD who did not undergo HSCT (untreated cohort) and on 65 patients who underwent transplantation (HSCT cohort) at 5 clinical sites. Kaplan-Meier (KM) estimates of 5-year overall survival (OS) from the time of CALD diagnosis were 55% (95% confidence interval [CI], 42.2% to 65.7%) for the untreated cohort and 78% (95% CI, 64% to 86.6%) for the HSCT cohort overall (P?=?.01). KM estimates of 2-year MFD-free survival for patients with gadolinium-enhanced lesions (GdE+) were 29% (95% CI, 11.7% to 48.2%) for untreated patients (n?=?21). For patients who underwent HSCT with GdE+ at baseline, with an NFS ≤1 and Loes score of 0.5 to ≤9 (n?=?27), the 2-year MFD-free survival was 84% (95% CI, 62.3% to 93.6%). Mortality rates post-HSCT were 8% (5 of 65) at 100days and 18% (12 of 65) at 1 year, with disease progression (44%; 7 of 16) and infection (31%; 5 of 16) listed as the most common causes of death. Adverse events post-HSCT included infection (29%; 19 of 65), acute grade II-IV graft-versus-host disease (GVHD) (31%; 18 of 58), and chronic GVHD (7%; 4 of 58). Eighteen percent of the patients (12 of 65) experienced engraftment failure after their first HSCT. Positive predictors of OS in the HSCT cohort may include donor-recipient HLA matching and lack of GVHD, and early disease treatment was predictive of MFD-free survival. GdE+ status is a strong predictor of disease progression in untreated patients.? This study confirms HSCT as an effective treatment for CALD when performed early. We propose survival without MFDs as a relevant treatment goal, rather than solely assessing OS as an indicator of treatment success.  相似文献   
5.
It is now possible to provide combination fixed/removable prosthetic restorations using only 1 dental alloy, such as CoCr, a nonprecious alloy. This alloy offers clinical performance and demonstrated corrosion resistance. This clinical report demonstrates use of a single CoCr alloy for metal-ceramic fixed partial dentures in conjunction with a mandibular removable partial denture.  相似文献   
6.
Clinical costs have become an important consideration in dental schools, and have been the subject of several recent studies. In order to determine the actual costs of endodontic procedures, we have attempted to identify the various components of root canal therapy. The present study is based on findings in a university hospital functioning within the context of the French health care system. A questionnaire was used to survey the major factors entering into the achievement of the clinical procedure. The endodontic treatments were performed on 100 1st or 2nd molars, by undergraduate students. The survey involves fixed, variable, direct and indirect costs, and takes into consideration the reimbursements made by the French health care system. Findings indicate that all procedures show an appreciable deficit with a significant difference between initial treatment and retreatment. The analysis of the survey questionnaire findings enables us to offer some recommendations in the area of undergraduate education, as well.  相似文献   
7.
Simon S  Lumley P  Tomson P  Pertot WJ  Machtou P 《Dental update》2008,35(2):110-2, 115-6
Crown down preparation is the most known and described technique since the introduction of Nickel Titanium (NiTi) rotary instruments in endodontics. This technique gives good results but has limitations, such as not addressing the initial anatomy of oval or dumb-bell shaped canals. The specific design of the Protaper instruments allows use of them with a different technique and, specifically, with a brushing motion in the body of the canal. The recent introduction of hand Protaper files has expanded the range of application of this system, especially in curved canals. The 'hybrid technique', using rotary and hand files, and the advantages of the combination of both instruments, are clearly described in this article. Used with this technique, the Protaper is a very safe system to use, and more controllable, for both inexperienced and experienced practitioners alike, than other systems. Clinical Relevance: To understand the precautions needed with rotary files, and how to use them to preserve the anatomy of the canal and get a tapered shaping, even in severely curved canals.  相似文献   
8.
We investigated safety issues and potential experimental confounds when performing functional magnetic resonance imaging (fMRI) investigations in human subjects with fully implanted, active, deep brain stimulation (DBS) systems. Measurements of temperature and induced voltage were performed in an in vitro arrangement simulating bilateral DBS during magnetic resonance imaging (MRI) using head transmit coils in both 1.5 and 3.0 T MRI systems. For MRI sequences typical of an fMRI study with coil-averaged specific absorption rates (SARs) less than 0.4 W/kg, no MRI-induced temperature change greater than the measurement sensitivity (0.1 degrees C) was detected at 1.5 T, and at 3 T temperature elevations were less than 0.5 degrees C, i.e. within safe limits. For the purposes of demonstration, MRI pulse sequences with SARs of 1.45 W/kg and 2.34 W/kg (at 1.5 T and 3 T, respectively) were prescribed and elicited temperature increases (>1 degrees C) greater than those considered safe for human subjects. Temperature increases were independent of the presence or absence of active stimulator pulsing. At both field strengths during echo planar MRI, the perturbations of DBS equipment performance were sufficiently slight, and temperature increases sufficiently low to suggest that thermal or electromagnetically mediated experimental confounds to fMRI with DBS are unlikely. We conclude that fMRI studies performed in subjects with subcutaneously implanted DBS units can be both safe and free from DBS-specific experimental confounds. Furthermore, fMRI in subjects with fully implanted rather than externalized DBS stimulator units may offer a significant safety advantage. Further studies are required to determine the safety of MRI with DBS for other MRI systems, transmit coil configurations and DBS arrangements.  相似文献   
9.
Accurate real-time models of soft tissue behavior are key elements in medical simulation systems. The need for fast computation in these simulations, however, often requires simplifications that limit deformation accuracy. Validation of these simplified models remains a challenge. Currently, real-time modeling is at best validated against finite element models that have their own intrinsic limitations. This study develops a physical standard to validate real-time soft tissue deformation models. We took CT images of a cube of silicone rubber with a pattern of embedded Teflon spheres that underwent uniaxial compression and spherical indentation tests. The known material properties, geometry and controlled boundary conditions resulted in a complete set of volumetric displacement data. The results were compared to a finite element model analysis of identical situations. This work has served as a proof of concept for a robust physical standard for use in validating soft tissue models. A web site has been created to provide access to our database: http://biorobotics.harvard.edu/truthcube/ (soon to be http://www.truthcube.org).  相似文献   
10.

Objective:

Borderline and antisocial personality disorders (PDs) share common clinical features (impulsivity, aggressiveness, substance use disorders [SUDs], and suicidal behaviours) that are greatly overrepresented in prison populations. These disorders have been associated biologically with testosterone and cortisol levels. However, the associations are ambiguous and the subject of controversy, perhaps because these heterogeneous disorders have been addressed as unitary constructs. A consideration of profiles of people, rather than of exclusive diagnoses, might yield clearer relationships.

Methods:

In our study, multiple correspondence analysis and cluster analysis were employed to identify subgroups among 545 newly convicted inmates. The groups were then compared in terms of clinical features and biological markers, including levels of cortisol, testosterone, estradiol, progesterone, and sulfoconjugated dehydroepiandrosterone (DHEA-S).

Results:

Four clusters with differing psychiatric, criminal, and biological profiles emerged. Clinically, one group had intermediate scores for each of the tested clinical features. Another group comprised people with little comorbidity. Two others displayed severe impulsivity, PD, and SUD. Biologically, cortisol levels were lowest in the last 2 groups and highest in the group with less comorbidity. In keeping with previous findings reported in the literature, testosterone was higher in a younger population with severe psychiatric symptoms. However, some apparently comparable behavioural outcomes were found to be related to distinct biological profiles. No differences were observed for estradiol, progesterone, or DHEA-S levels.

Conclusions:

The results not only confirm the importance of biological markers in the study of personality features but also demonstrate the need to consider the role of comorbidities and steroid coregulation.  相似文献   
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