Search

Abstract: Objectives: Although the aortic-valve-sparing (AVS) reimplantation technique according to David has shown favorable durability results in mid-term and long-term studies, composite valve grafting (CVG) according to Bentall is still considered the standard procedure. Methods: Retrospectively, we evaluated the results of aortic root replacement of patients with Marfan syndrome (MFS) who underwent surgery between January 1995 and January 2010. MFS was diagnosed using the Ghent criteria. AVS was used in 58 patients and CVG in 30 patients with MFS. AVS was done for aortic-root aneurysm (n =48) or aortic dissection type A (n =10). CVG was used for aortic-root aneurysm in 14 patients or aortic dissection type A in 16 patients. The mean follow-up was 3.2 (95% CI: 2.4–4.2) years. Results: In both groups, 30-day mortality was 0%. Three patients (10.0%) in the CVG group required resternotomy for postoperative bleeding versus two patients (3.4%) in the AVS group (p =0.3). At follow-up, mortality was 10% in the CVG group versus 3.4% in the AVS group (p =0.3). Re-operation was required in two patients (3.4%) after AVS and in three patients after CVG (10%) (p =0.3). Three patients (10.0%) who underwent CVG had endocarditis and two patients (6.7%) had a stroke during follow-up, whereas no endocarditis and stroke occurred after AVS. After 14 years, stratified event-free survival was better in the AVS group (event-free survival was 82.3% vs 58.6%, log-rank test p =0.086), especially after aneurysm (p =0.057). After 10 years, freedom from aortic regurgitation ≥II° in the AVS group was 80% for aneurysm and 50% after dissection (p =0.524). Conclusion: The reimplantation technique according to David was associated with excellent survival, good valve function and a low rate of re-operation, endocarditis, and stroke. There was a trend to better event-free survival for AVS patients making it the procedure of choice in MFS patients. [Copyright &y& Elsevier]

Urban centres produce most of the world''s waste and between a third and a half goes uncollected. The answer to the problem of waste disposal lies partly in agriculture, as waste can be extremely nutrient-rich. In the last decade there has been a tremendous increase in the developing world in total city area under informal food production and there are many examples of waste recycling onto the urban or peri-urban plots. Farmers on the Jos Plateau, Nigeria, have developed a successful soil fertility management strategy based on the combination of inorganic fertilisers, manure and urban waste ash. This study sought to provide some preliminary data on urban waste ash produced by open burning and used in farming in a developing country. Ash samples were collected from different locations around Jos and tested for C, N, pH, P, Na, K, Ca, Mg, Fe, Mn, Zn, Cu, Ni, Cd and Pb. It was found that ash is an effective liming material (because of the high pH, and high Ca, Mg and K contents), and has the potential to contribute significant quantities of micro-nutrients such as Mn, Zn and Cu. Ash, however, is far from being a homogenous material and its variability means that its fertilising potential will vary between batches and that, even if mean and median levels are low, there is the risk of the formation of localised areas of soil with excessive heavy metal contents (this is particularly the case with Pb). Further research is required to determine the plant-availability of these elements in the ash and to assess the wider environmental and health implications of uncontrolled, open burning of waste as a means of producing ash for agricultural purposes. [Copyright &y& Elsevier]

Discusses a study which described a spectral parameterization of mean-flow forcing due to breaking gravity waves for application in the equations of motion in atmospheric models. Background of the study; Spectral parameterization; Result of the applications of the parameterization.

Examines the role of gravity waves to the zonal winds in the equatorial stratosphere simulated by a type of tropical convection. Utilization of two-dimensional cloud-resolving model; Description of the profiles of zonal forcing; Estimation of the magnitude of the zonal forcing; Comparison between simulations regarding background winds.

Studies vertically propagating waves generated by deep convection using two-dimensional simulation of a midlatitude squall line. General model description; Physical interpretation of the spectral analysis results; Characteristics of the stratospheric wave field.

The laterodorsal nucleus (LDN) of the thalamus provides a prominent afferent projection to the postsubiculum (dorsal presubiculum). To characterize synaptic transmission in this pathway, we placed stimulating electrodes in the LDN and recorded fEPSPs elicited in the postsubiculum of urethane-anesthetized rats. LDN stimulation elicited a source-sink dipole between the deep and superficial layers of the postsubiculum, respectively, consistent with anatomical evidence for the termination of thalamic afferents in the superficial layers of the structure, and the existence of deep layer neurons with apical dendrites extending into these layers. Postsubicular fEPSPs were typically 0.5-1.0 mV in amplitude, with a peak latency of approximately 6 ms. Consistent with anatomical observations, the short onset latency of fEPSPs elicited by LDN stimulation, and their ability to follow a 60-Hz train of stimulation, indicate that the projection is monosynaptic. Paired-pulse stimulation revealed pronounced paired-pulse depression that was maximal at 100 ms, suggesting that initial release probabilities are high at LDN-postsubiculum synapses, in common with many neocortical pathways. A conventional tetanus protocol that yields LTP in hippocampal pathways had no effect on postsubicular fEPSPs, but long-term depression could be induced by 60-Hz stimulation. Drug infusion studies revealed that synaptic transmission in the LDN-postsubiculum projection is predominantly AMPA-receptor mediated. Rats were implanted with indwelling infusion cannulae targeting the postsubiculum, and, after a recovery period, were anaesthetized withurethane, and implanted with stimulating and recording electrodes. Infusion of CNQX almost completely abolished postsubicular fEPSPs, whereas D-AP5 had little effect. However, 60-Hz LTD was blocked by D-AP5 infusion, revealing that this form of synaptic plasticity is NMDA-receptor dependent. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Background: The relationship of aortic valve dysfunction and ascending aortic aneurysm is unclear in adults with bicuspid aortic valve disease. Methods: We retrospectively studied 134 consecutive out-patients (98 men, 36 women aged 43±18years) with bicuspid aortic valve disease. To investigate the relationship of ascending aortic aneurysm and aortic valve dysfunction we exclusively considered severe pathologies that required treatment by surgical or percutaneous intervention. Results: Of 134 patients, 39 had aortic valve dysfunction without concomitant ascending aortic aneurysm which had been treated previously with isolated valve surgery or percutaneous valvuloplasty comprising 25 patients with aortic stenosis (19%) and 14 patients with aortic regurgitation (10%). Conversely, 26 patients had ascending aortic aneurysm which had been treated previously with aortic surgery (19%). Of these, ascending aortic aneurysm was associated with severe aortic stenosis in 13 patients and with severe aortic regurgitation in 7 patients, whereas aneurysm was unrelated to severe aortic valve dysfunction in the remaining 6 patients including 2 without any degree of aortic valve dysfunction. The maximal aortic diameters were similar at the time of aortic surgery irrespective of presence of severe aortic valve dysfunction (P =.527). Other characteristics of patients with ascending aortic aneurysm were also similar irrespective of presence or type of aortic valve dysfunction. Conclusion: The majority of patients with bicuspid aortic valve disease exhibit ascending aortic aneurysm in conjunction with severe aortic valve dysfunction. However, in our study 6 of 134 (5%) of persons with bicuspid aortic valve disease developed ascending aortic aneurysm without aortic valve dysfunction. [Copyright &y& Elsevier]

Highlights from the article: Gastroesophageal reflux disease (GERD) is defined as reflux of stomach contents causing troublesome symptoms and/or complications.[1] Typical symptoms of GERD include heartburn, regurgitation, a combination of the two, and dysphagia. The present study highlights that GERD symptoms are infrequent among Indian patients with cirrhosis and ascites. In a study on Chinese population on the prevalence of reflux esophagitis in patients with cirrhosis, it was noted that most patients with reflux esophagitis were asymptomatic.

Abstract: Background: Until today, FBN1 gene mutation characteristics were not compared with clinical features for the prediction of mitral valve disease progression. Methods: Therefore, we conducted a study of 116 patients (53 men, 63 women aged 33±15years) with a causative FBN1 gene mutation and ≤moderate mitral valve regurgitation at baseline. Results: During 7.4±6.8years 30 patients developed progression of mitral valve regurgitation≥1 grade (primary endpoint), and 26 patients required mitral valve surgery (secondary endpoint). Cox regression analysis identified an association of atrial fibrillation (hazard ratio (HR)=2.703; 95% confidence interval (CI) 1.013–7.211; P =.047), left ventricular ejection fraction (HR=.970; 95%CI .944–.997; P =.032), indexed end-diastolic left ventricular diameter (HR=15.165; 95%CI 4.498–51.128; P <.001), indexed left atrial diameter (HR=1.107; 95%CI 1.045–1.173; P =.001), tricuspid valve prolapse (HR=2.599; 95%CI 1.243–5.437; P =.011), posterior leaflet prolapse (HR=1.075; 95%CI 1.023–1.130; P =.009), and posterior leaflet thickening (HR=3.368; 95%CI 1.265–8.968; P =.015) with progression of mitral valve disease, whereas none of the FBN1 gene mutation characteristics were associated with progression of mitral valve disease. However, Cox regression analysis identified a marginal relationship of FBN1 gene mutations located both in a transforming-growth-factor beta-binding protein-like (TGFb-BP) domain (HR=3.453; 95%CI .982–12.143; P =.053), and in the calcium-binding epidermal growth factor-like (cbEGF) domain (HR=2.909; 95%CI .957–8.848; P =.060) with mitral valve surgery, a finding that was corroborated by Kaplan–Meier analysis (P =.014; and P =.041, respectively). Conclusion: Clinical features were better predictors of mitral valve disease progression than FBN1 gene mutation characteristics. [Copyright &y& Elsevier]

The atmospheric aerosol has a large influence on global climate through its ability of scattering and absorbing electromagnetic radiation, which affect the Earth's radiative balance. Characteristics, such as size distribution, chemical composition and hygroscopic properties are important for improving global climate model projections of natural sea spray aerosols, which are numerically dominant in the global aerosol budget. Previous experimental studies in coastal locations revealed a complex mixing between natural and anthropogenic aerosols. This complexity makes it difficult to characterize the behavior of natural sea spray aerosols in a simplified form that is suitable for global models. The aim of the present paper is to characterize the size distributions of natural sea spray aerosols at a coastal site in False Bay, South Africa. The opening of False Bay towards the Southern Ocean with unlimited fetch from Antarctica provides a unique opportunity to measure and focus on pristine marine air masses solely. A large observational data set from the First European-South African Transmission Experiment (FESTER) was analyzed and two case studies are presented to illustrate the contribution of sea spray to aerosol size distributions under pure marine and mixed air mass conditions, respectively. A set of conditions for measuring pure marine aerosols in False Bay was established. The results of the relationship of aerosol concentrations with wind speed reveals the distinct behavior of natural sea spray aerosols and demonstrates the pure marine influence of the Southern Ocean in False Bay. Comparison of the aerosol size distributions to a coastal site in the Mediterranean Sea, attest to the contribution of sea spray to aerosol size distributions in False Bay. • Unique location and orography of False Bay allow for pure marine conditions. • Selection process allows for measurement of sea spray aerosols exclusively. • Rare occurrence to measure influence from Southern Ocean at coastal site. • Comparison to Northern hemisphere coastal sites attest to pure marine conditions. [ABSTRACT FROM AUTHOR]

Mitral valve prolapse has a prevalence of 2% to 3% in the general population, with adverse outcomes such as mitral valve regurgitation (MVR), heart failure, and endocarditis. Predictors of outcomes are used in idiopathic mitral valve prolapse for the timing of surgery, but such predictors are unknown in Marfan syndrome. Therefore, a population-based cohort study of 112 patients (49 male, 63 female; mean age 34 ± 15 years) with classic Marfan syndrome and mitral valve prolapse with moderate or less MVR at baseline was conducted. During 4.6 ± 3.6 years of follow-up, progression of MVR was observed in 41 patients and valve-related events, which comprised mitral valve endocarditis (7 events), heart failure (5 events), and mitral valve surgery (25 events), were observed in 31 patients. Multivariate Cox proportional-hazards regression analysis identified a flail mitral leaflet (hazard ratio [HR] 3.262, 95% confidence interval [CI] 1.406 to 7.566, p = 0.006) and increased indexed end-systolic left ventricular diameters (HR 1.113, 95% CI 1.043 to 1.188, p = 0.001) as independent predictors of progression of MVR. Similarly, mitral valve–related events were independently predicted by a flail mitral leaflet (HR 5.343, 95% CI 2.229 to 12.808, p <0.001), and mild (HR 14.336, 95% CI 1.873 to 109.755, p = 0.01) or moderate (HR 16.849, 95% CI 2.205 to 128.76, p = 0.006) degree of MVR. Conversely, aortic dilatation, dural ectasia, and sporadic mode of inheritance were not associated with outcome. In conclusion, the same clinical determinants that predict outcomes in idiopathic mitral valve prolapse also predict outcomes in mitral valve prolapse associated with Marfan syndrome. [ABSTRACT FROM AUTHOR]

Mitral valve (MV) prolapse (MVP) has a high prevalence of 2% to 3% in the general population and thus constitutes the most common cause of severe nonischemic MV regurgitation (MVR). MVP is also common in persons with the Marfan syndrome. However, to date, a large-scale population-based cohort study using modern echocardiographic techniques has not been performed, and the frequency of MVP and the relation of MV dysfunction and age have not been investigated. Therefore, we conducted a population-based cohort study of 204 patients (108 males and 96 females, aged 31.2 ± 16.4 years) with classic Marfan syndrome. We performed echocardiographic follow-up of 174 patients for a mean of 4.4 ± 4.3 years. On the initial or subsequent echocardiographic scan, MVP was present in 82 patients (40%), severe MVR in 25 (12%), and MV endocarditis in 5 patients (2.5%). At 30 years of age, the Weibull cumulative distribution was 42.6% (95% confidence interval [CI] 36% to 50%) for MVP, 56.5% (95% CI 49.3% to 64%) for MVR of any degree, 6.7% (95% CI 3.9% to 11.3%) for severe MVR, and 0.92% (95% CI 0.21% to 3.91%) for MV endocarditis. The cumulative hazard for severe MVR and MV endocarditis was estimated to increase with age. MVP was associated with dural ectasia (p = 0.01), ectopia lentis (p = 0.02), and skeletal involvement (p <0.001). Severe MVR was related to tricuspid valve prolapse (p = 0.002) and to the sporadic form of the Marfan syndrome (p = 0.006). In conclusion, MVP was comparatively frequent in patients with the Marfan syndrome and carries an increased risk of progression to severe MVR and endocarditis, especially in older adults. [ABSTRACT FROM AUTHOR]

Obstructive and central sleep apneas are treatable disorders, which contribute to cardiovascular morbidity in older adults. Younger adults with Marfan syndrome may also be at risk for sleep apnea, but the relation between cardiovascular complications and sleep apnea is unknown. We used MiniScreen8 portable monitoring devices for polygraphy in 68 consecutive adults with Marfan syndrome (33 men, 35 women, 41 ± 14 years old) to investigate frequency of sleep apnea and its relation to cardiovascular morbidity. The apnea–hypopnea index (AHI) was 6 to 15/hour in 14 subjects (mild sleep apnea, 21%), and AHI was >15/hour in 7 subjects (moderate or severe sleep apnea, 10%). Among established risk factors for sleep apnea, only older age (Spearman rho = 0.35, p = 0.004) and body mass index (rho = 0.26, p = 0.03) were associated with increased AHI. Of all cases of apnea, 12 ± 27 were obstructive, 11 ± 25 central, and 3 ± 9 mixed. AHI was associated with decreased left ventricular ejection fraction (rho = −0.33, p = 0.01), increased N-terminal pro–brain natriuretic peptide levels (rho = 0.35, p = 0.004), enlarged descending aortic diameters (rho = 0.44, p = 0.001), atrial fibrillation (phi = 0.43, p = 0.002), and mitral valve surgery (phi = 0.34, p = 0.02). Of these, left ventricular ejection fraction, N-terminal pro–brain natriuretic peptide levels, atrial fibrillation, and mitral valve surgery were associated with AHI independently of age and body mass index. We found similar associations with oxygen desaturation index. In conclusion, sleep apnea exhibits increased frequency in Marfan syndrome and is not predicted by classic risk factors. Obstructive and central sleep apneas may relate to cardiovascular disease variables. [Copyright &y& Elsevier]

The coastal aerosol represents a complex mixing between sea spray aerosols locally generated at the sea surface and a component generated by natural and/or anthropogenic sources on the nearby land. The aim of this paper is to study the atmospheric concentrations of carbonaceous compounds as measured in the coastal zone of the Northern Adriatic Sea between April 2017 and April 2018. The results show a quite large contribution of carbonaceous compounds, even when the sampled air mass is predominantly maritime. Although it is generally assumed that 70% and 90% of bulk organic carbon (OC) and elemental carbon (EC) concentrations, respectively, are found in the fine mode, we observed higher OC and EC concentrations in the coarse fraction (up to about 37% and 25%, respectively). This confirms the occurrence of mixing between anthropogenic matter and sea spray, mainly composed of coarse aerosol particles, during the atmospheric transport over the Mediterranean basin. • Organic and elemental carbon size distributions measured at an off-shore platform near to an industrial coastal area. • Thermo-optical analysis performed on impactor samples by ad-hoc solutions. • Large organic and elemental carbon concentrations were measured. • Occurrence of external mixing between sea spray and anthropogenic matter. [ABSTRACT FROM AUTHOR]