Increased risk and severity of unprovoked venous thromboembolism with clustering cardiovascular risk factors for atherosclerosis: Results of the REMOTEV registry.

BACKGROUND: The role of cardiovascular risk factors (CVRF) for atherosclerosis in venous thromboembolic disease (VTE) is controversial. The aim of this study was to evaluate the impact of CVRF and their cumulative effects on the occurrence of unprovoked VTE, severity, recurrence and survival. METHODS AND RESULTS: This is a prospective cohort from the REMOTEV registry including all consecutively hospitalized patients for acute symptomatic VTE. From November 2013 to December 2016, 515 patients with 6months follow-up (FU) were selected for the analysis. Events were classified as unprovoked or provoked VTE. In univariate analysis, hypertension (OR 1.44, [95% CI 1.01-2.06]), diabetes (OR 2.07, [95% CI: 1.25-3.55]) and age (OR 1.94, [95% CI: 1.31-2.88]) were significantly associated with the risk of unprovoked VTE. After adjustment, diabetes (OR 1.82, [95% CI: 1.07-3.18]) and age (OR 1.79, [95% CI: 1.15-2.8]) remained associated with the risk of unprovoked VTE. The proportion of unprovoked VTE increased significantly with the number of CVRF adjusted for thrombophilia (1 CVRF: OR 3 [95% CI: 1.44-6.52]) 2 CVRF: OR 4.33 [95% CI: 2.07-9.49] and ≥3 CVRF: OR 4.58 [95% CI: 2.27-9.7]). The severity of pulmonary embolism was significantly associated with CVRF clustering. There were more VTE recurrences and deaths during the 6months of FU with cumulative CVRF. CONCLUSION: The risks of unprovoked VTE and PE severity are associated with clustering CVRF. The role of cumulative CVRF predominates rather than the specific burden of each of the CVRF in the risk of VTE occurrence.

Incidence and risk factors of venous thromboembolism: Peculiarities in psychiatric institutions.

INTRODUCTION: The objectives of this study were to assess the incidence and risk factors for venous thromboembolism (VTE) in a population of patients hospitalized in a psychiatric setting. MATERIAL AND METHODS: Episodes of VTE occurring in patients hospitalized at the Erstein Hospital (France), specialized in psychiatry, were retrospectively identified from a computerized database. The clinical, somatic, psychiatric and therapeutic characteristics of each patient were analyzed in comparison with a control population composed of patients of similar age and sex, hospitalized during the same period in a psychiatric setting but who did not suffer from VTE. RESULTS: Between January 2012 and October 2015, 12,320 patients were hospitalized. Forty-one patients experienced an episode of VTE, giving an incidence of 47.8per1000patient-years (3.32 cases per 1000 patients). Restriction of mobility (restraint or confinement), somatic clinical profile, psychiatric diagnosis or psychotropic treatment were not associated with an increased risk of VTE. The event occurred within the first 48h of hospitalization for 31.7% of patients, and within the first week for 56.1%. Time to onset for the occurrence of VTE between admission and the end of the first week was significantly associated with acute decompensation of a chronic psychiatric pathology (p=0.003). CONCLUSION: The incidence of VTE in a psychiatric setting is high. Acute decompensation of a chronic psychiatric pathology is associated with a risk of VTE.

Single source dual energy CT: What is the optimal monochromatic energy level for the analysis of the lung parenchyma?

OBJECTIVE: To determine the optimal monochromatic energy level for lung parenchyma analysis in spectral CT. METHODS: All 50 examinations (58% men, 64.8±16yo) from an IRB-approved prospective study on single-source dual energy chest CT were retrospectively included and analyzed. Monochromatic images in lung window reconstructed every 5keV from 40 to 140keV were independently assessed by two chest radiologists. Based on the overall image quality and the depiction/conspicuity of parenchymal lesions, each reader had to designate for every patient the keV level providing the best diagnostic and image quality. RESULTS: 72% of the examinations exhibited parenchymal lesions. Reader 1 picked the 55keV monochromatic reconstruction in 52% of cases, 50 in 30% and 60 in 18%. Reader 2 chose 50keV in 52% cases, 55 in 40%, 60 in 6% and 40 in 2%. The 50 and 55keV levels were chosen by at least one reader in 64% and 76% of all patients, respectively. Merging 50 and 55keV into one category results in an optimal setting selected by reader 1 in 82% of patients and by reader 2 in 92%, with a 74% concomitant agreement. CONCLUSION: The best image quality for lung parenchyma in spectral CT is obtained with the 50-55keV monochromatic reconstructions.

Five Year Outcomes of Surgical Treatment for Popliteal Artery Entrapment Syndrome.

OBJECTIVE/BACKGROUND: The aim of this study was to evaluate long-term outcomes following surgery for popliteal artery entrapment syndrome. METHODS: A retrospective study of all patients that underwent surgery for popliteal artery entrapment syndrome between January 2003 and December 2009 was performed. Patient demographic data, clinical features, imaging modalities, and surgical management were recorded. The primary outcome was 5 year patency. RESULTS: Eighteen patients (25 limbs) underwent surgery. The mean age at the time of surgical procedure was 35 (median 35 years; range 15-49). Presentation was bilateral in seven patients (39%). Diagnosis was made using various imaging modalities, including position stress test, Duplex ultrasonography, computed tomography angiography, magnetic resonance imaging and conventional angiography. In four limbs the popliteal artery was compressed and undamaged (16%), and treatment consisted of musculo-tendinous division alone. In 16 limbs the popliteal artery was damaged with lesions limited to the popliteal artery (64%) where treatment consisted of venous interposition. In five limbs lesions extended beyond the popliteal artery (20%) and procedures included one below knee femoro-popliteal bypass, three femoro-posterior tibial bypasses, and one popliteo-posterior tibial bypass. Musculo-tendinous division was associated with vascular reconstruction in 19 limbs (90%). Mean follow up was 82 months (median 81 months, range 60-120). Five year patency was 84%. CONCLUSION: Long-term outcomes of surgical procedures performed for popliteal artery entrapment syndrome can be considered satisfactory.

[Contribution of mathematical models and biomechanical properties in predicting the risk of abdominal aortic aneurysm rupture]. / Apport des modèles mathématiques et des études biomécaniques dans la prédiction du risque de rupture des anévrysmes de l'aorte abdominale.

INTRODUCTION: Rupture is the worst outcome of abdominal aortic aneurysm (AAA). The decision to operate should include counterbalancing the risk of aneurysm rupture against the risk of aneurysm repair, within the context of a patient's overall life expectancy. Current surgical guidelines are based on population studies, and important variables are missed in predicting individual risk of rupture. METHODS: In this literature review, we focused on the contribution of biomechanical and mathematical models in predicting risk of AAA rupture. RESULTS: Anatomical features as diameter asymmetry and lack of tortuosity are shown to be anatomical risk factors of rupture. Wall stiffness (due to modifications of elastin and collagen composition) and increased inflammatory response are also factors that affect the structural integrity of the AAA wall. Biomechanical studies showed that wall strength is lower in ruptured than non-ruptured AAA. Intra-luminal thrombus also has a big role to play in the occurrence of rupture. Current mathematical models allow more variables to be included in predicting individual risk of rupture. CONCLUSION: Moving away from using maximal transverse diameter of the AAA as a unique predictive factor and instead including biological, structural and biomechanical variables in predicting individual risk of rupture will be essential in the future and will help gain precision and accuracy in surgical indications.

Iterative reconstruction in single source dual-energy CT pulmonary angiography: Is it sufficient to achieve a radiation dose as low as state-of-the-art single-energy CTPA?

OBJECTIVE: Dual-energy (DE) brings numerous significant improvements in pulmonary CT angiography (CTPA), but is associated with a 15-50% increase in radiation dose that prevents its widespread use. We hypothesize that thanks to iterative reconstruction (IR), single source DE-CTPA acquired at the same radiation dose that a single-energy examination will maintain an equivalent quantitative and qualitative image quality, allowing a more extensive use of the DE technique in the clinical routine. MATERIAL AND METHODS: Fifty patients (58% men, mean age 64.8yo ± 16.2, mean BMI 25.6 ± 4.5) were prospectively included and underwent single source DE-CTPA with acquisition parameters (275 mA fixed tube current, 50% IR) tweaked to target a radiation dose similar to a 100 kV single-energy CTPA (SE-CTPA), i.e., a DLP of 260 mGy cm. Thirty patients (47% men, 64.4yo ± 18.6, BMI 26.2 ± 4.6) from a previous prospective study on DE-CTPA (375 mA fixed tube current, reconstruction with filtered-back projection) were used as the reference group. Thirty-five consecutive patients (57% men, 65.8yo ± 15.5, BMI 25.7 ± 4.4) who underwent SE-CTPA on the same scanner (automated tube current modulation, 50% IR) served as a comparison. Subjective image quality was scored by two radiologists using a 5-level scale and compared with a Kruskal-Wallis nonparametric test. Density measurements on the 65 keV monochromatic reconstructions were used to calculate signal-to-noise (SNR) and contrast-to-noise (CNR) ratios that were compared using a Student's t test. Correlations between image quality, SNR, CNR and BMI were sought using a Pearson's test. p<0.05 was considered significant. RESULTS: All examinations were of diagnostic quality (score ≥ 3). In comparison with the reference DE-CTPA and the SE-CTPA protocols, the DE-IR group exhibited a non-inferior image quality (p=0.95 and p=0.21, respectively) and a significantly lower mean image noise (p<0.01 and p=0.01) thus slightly improving the SNR (p=0.09 and p=0.47) and the CNR (p=0.12 and p=0.51). There was a strong negative relationship between BMI and SNR/CNR (ρ=-0.59 and -0.55 respectively), but only a moderate negative relationship between BMI and image quality (ρ=-0.27). CONCLUSION: With iterative reconstruction, objective and subjective image quality of single source DE-CTPA are preserved even though the radiation dose is lowered to that of a single-energy examination, overcoming a major limitation of the DE technique and allowing a widespread use in the clinical routine.

[Post-denervation renal artery stenosis - a matter of concern?]. / Les sténoses artérielles rénales post-dénervation - une problématique préoccupante ?

Renal denervation, an invasive technique indicated in resistant hypertension patients insufficiently controlled by antihypertensive drugs, has a good safety profile. However, an increasing number of post-denervation renal artery stenosis cases has recently been reported. We describe the case of a 49-year-old woman with resistant hypertension who was referred to our university hypertension center for renal sympathetic denervation. Her daily treatment included six antihypertensive drugs. CT angiography prior to denervation showed no renal artery stenosis or vessel wall lesions. A standard renal denervation procedure using the St Jude protocol was performed. After an initial improvement in blood pressure profile, she presented with a blood pressure impairment at 3 months after renal denervation leading to the diagnosis of a severe right renal artery stenosis.

Current optimal morphological evaluation of peripheral arterial diseases.

Imaging plays a central role in the management of peripheral arterial diseases (PAD), emphasized by the continuously increasing use of modern cross-sectional imaging and the corresponding decline of digital subtraction angiography (DSA) in the diagnostic setting. Imaging is sometimes used as a screening tool in high-risk individuals. In symptomatic patients, imaging is mandatory to make an accurate positive diagnosis, grade the severity and the extent of the abnormalities, carefully choose and plan the best therapeutic option and provide adequate follow-up. Non-invasive diagnosis of PAD can be made by Doppler ultrasonography, magnetic resonance angiography (MRA) and computed tomography angiography (CTA). Given the major technological breakouts over the last decade, MRA and especially CTA are nowadays mature and precise enough to properly answer all the questions raised in symptomatic patients. This review article aims at describing state-of-the-art non-invasive imaging of PAD, its involvement in the decision-making for the vascular surgeon and the future trends and developments expected in the coming years.

Popliteal artery entrapment syndrome.

Intermittent claudication is frequently encountered in vascular surgical practice in atherosclerotic patients. However, it may also be observed in a younger subset of patients without any cardiovascular risk factors and can represent a challenging diagnosis. Popliteal artery entrapment syndrome is rare but can cause intermittent claudication in young people. There is a lack of consensus about optimal strategies or diagnosis and management, particularly for variants such as functional popliteal entrapment. Since the first description in 1959, knowledge of the pathology and the underlying anatomic abnormalities was advanced through sporadic publications of case reports and small case series, but popliteal artery entrapment syndrome still remains a rare anatomic abnormality. It can be difficult to differentiate from other causes of lower limb pain in young patients, and diagnosis can be challenging. We propose to review clinical symptomatology, classification, radiological diagnosis and treatment of popliteal entrapment syndrome.

Experimental demonstration of four-party quantum secret sharing.

Secret sharing is a multiparty cryptographic task in which some secret information is split into several pieces which are distributed among the participants such that only an authorized set of participants can reconstruct the original secret. Similar to quantum key distribution, in quantum secret sharing, the secrecy of the shared information relies not on computational assumptions, but on laws of quantum physics. Here, we present an experimental demonstration of four-party quantum secret sharing via the resource of four-photon entanglement.

Modern MRI tools for the characterization of acute demyelinating lesions: value of chemical shift and diffusion-weighted imaging.

Acute demyelinating lesions occur in various inflammatory disorders of the CNS. Apart from multiple sclerosis, most cases can be attributed to an overshooting immunological response to infectious agents called acute disseminated encephalomyelitis (ADEM). ADEM, which is mostly characterized by a monophasic course, has a multiphasic variant (MDEM). The early application of corticosteroids has been shown to be beneficial for the outcome; thus, an early diagnosis is highly desirable. Furthermore, the differential diagnosis ruling out neoplastic disorders may be difficult using conventional MRI alone. The potential diagnostic value of advanced MR techniques such as chemical shift imaging (CSI) and diffusion-weighted imaging (DWI) was investigated in a patient with MDEM, who had a new lesion in continuity with the initial disease manifestation. CSI was performed at 1.5 T with a long echo time of 135 ms for the evaluation of N-acetyl-aspartate (NAA) and choline (Cho) and with short TE of 30 ms for macromolecules (mm) and myo-Inositol (mI). DWI was performed using a single-shot isotropic EPI sequence. Whereas acute and chronic areas of demyelination were neither distinguishable on T2- nor on contrast-enhanced T1-weighted images, CSI and DWI revealed different metabolite concentrations and diffusion characteristics within the composite lesion, clearly separating acute from chronic areas of demyelination. In conclusion, the addition of CSI and DWI may add to the diagnostic power of MRI in the setting of demyelinating disorders by identifying areas of acute and chronic demyelination, even in the absence of contrast enhancement.

Aversive racism and selection decisions: 1989 and 1999.

The present study investigated differences over a 10-year period in whites' self-reported racial prejudice and their bias in selection decisions involving black and white candidates for employment. We examined the hypothesis, derived from the aversive-racism framework, that although overt expressions of prejudice may decline significantly across time, subtle manifestations of bias may persist. Consistent with this hypothesis, self-reported prejudice was lower in 1998-1999 than it was in 1988-1989, and at both time periods, white participants did not discriminate against black relative to white candidates when the candidates' qualifications were clearly strong or weak, but they did discriminate when the appropriate decision was more ambiguous. Theoretical and practical implications are considered.

Reducing intergroup bias: elements of intergroup cooperation.

The authors examined the potentially separable contributions of 2 elements of intergroup cooperation, interaction and common fate, and the processes through which they can operate. The manipulation of interaction reduced bias in evaluative ratings, which supports the idea that these components are separable, whereas the manipulation of common fate when the groups were interacting was associated with lower bias in nonverbal facial reactions in response to contributions by in-group and out-group members. Whereas interaction activated several processes that can lead to reduced bias, including decategorization, consistent with the common in-group identity model (S. L. Gaertner, J. F. Dovidio, P. A. Anastasio, B. A. Bachman, & M. C. Rust, 1993) as well as M. Hewstone and R. J. Brown's (1986) group differentiation model, the primary set of mediators involved participants' representations of the memberships as 2 subgroups within a superordinate entity.

Improved survival and amelioration of nephrotoxic nephritis in intercellular adhesion molecule-1 knockout mice.

Intercellular adhesion molecule-1 (ICAM-1) expression is upregulated in nephrotoxic nephritis, a model of human rapidly progressive glomerulonephritis. To evaluate the pathogenetic relevance of ICAM-1 in this model, nephrotoxic nephritis was induced in ICAM-1 knockout mice and genetic controls. Mice were preimmunized with rabbit IgG in complete Freund's adjuvant. Seven days later they received rabbit anti-mouse glomerular basement membrane IgG. The early humoral immune responses (levels of circulating mouse anti-rabbit IgG, glomerular deposition of rabbit and mouse IgG and mouse C3c) were not altered in ICAM-1 knockout mice. During 28 d of follow-up, 3 of 19 control nephritic mice and 0 of 16 ICAM-1 knockout mice died. Proteinuria was high in nephritic control mice (means 10 to 12 mg/24 h at all time points investigated) and significantly reduced in nephritic ICAM-1 knockout mice (means <4.4 mg). Mean serum creatinine rose from 29 micromol/L at day -7 to 48 micromol/L (day 28) in nephritic control mice. This increase in serum creatinine was significantly lower in ICAM-1 knockout mice: 27 (day -7) and 36 micromol/L (day 28). Histologic analysis at day 28 revealed that ICAM-1 deficiency in nephrotoxic nephritis mice led to significantly reduced glomerular crescent formation (2+/-3% in ICAM-1 knockout mice versus 13+/-8% in nephritic controls) and tubulointerstitial injury (score 0.4+/-0.4 versus 2.0+/-1.1). By immunohistochemistry, ICAM-1 deficiency in nephritic mice led to significantly reduced (peri-)glomerular and/or interstitial macrophage influx, alpha-smooth muscle actin expression, and type IV collagen accumulation. These data indicate that ICAM-1 is a central mediator of glomerular and tubulointerstitial injury in murine nephrotoxic nephritis.

Intergroup bias: status, differentiation, and a common in-group identity.

The present research examined factors that moderate and mediate the reduction of intergroup bias. Two 3-person laboratory groups, which had first worked separately on a task, were informed prior to intergroup contact that (a) the groups were equal or unequal in status based on their task performance, and (b) they had been working on the same or on different task dimensions. Consistent with M. Hewstone and R. J. Brown's (1986) mutual intergroup differentiation model, bias was eliminated when the groups' areas of expertise were differentiated and equally valued (i.e., in the equal status-different dimensions conditions). Moreover, as expected on the basis of the common in-group identity model, more inclusive group representations mediated this effect. The findings of the present research thus offer a theoretical integration that can suggest interventions to facilitate positive intergroup contact.

Influence of calving season and stocking rate on birth weight and weaning weight of Simmental-sired calves from Brahman-Hereford F1 dams.

Braham-Hereford F1 dams have been used to evaluate the influence of grazing pressure on forage attributes and animal performance at the Texas A&M University Agricultural Research Center at Overton. Data for this study were compiled from 1,909 records of Simmental-sired calves born to Braham-Hereford F1 cows from 1975 to 1990. Birth weight and weaning weight were analyzed independently to estimate the influence of year, season of birth, dam age, weaning age, and sex of calf. The effect of stocking rate as represented by levels of forage availability on weaning weights and subsequent birth weights was measured. Within the fall and winter calving seasons, lactating dams grazing at a high stocking rate produced calves with the lowest subsequent birth weights. Lactating dams assigned to creep-fed treatments had calves with the heaviest subsequent birth weights. Although dams that were less than 3.5 yr of age had calves with the lightest birth weights, there was no apparent decline in birth weight of calves from dams 12 to 17 yr old. Year, sex of calf, age of dam, stocking rate, season of birth, age at weaning, and birth weight were significant factors affecting weaning weight (P less than .01). Fall-born calves grazing cool-season annual pastures were heavier at weaning (267.6 kg) than either winter- (252.0 kg) or spring-born calves (240.9 kg). A stocking rate x season-of-birth interaction was observed for birth weight and weaning weight (P less than .05). Differences in weaning weight from low- vs high-stocked pastures were greater for fall-born calves (61.6 kg) than for winter-born calves (48.7).(ABSTRACT TRUNCATED AT 250 WORDS)