Assessing the toxicity of safer by design CuO surface-modifications using terrestrial multispecies assays.

Safer by design (SBD) modifications of nanomaterials (NMs) have been pursued, aiming to maintain functionality and yet reduce hazard and support sustainable nanotechnology. The present case study involves copper oxide nanomaterials (CuO NMs) used in paint that have been surface modified by a SBD approach to particles coated with citrate (CIT-), ascorbate (ASC-), polyethylenimine (PEI+), and polyvinylpyrrolidone (PVP). We assessed the effect of the 4 different surface modified (CIT, ASC, PVP and PEI) NMs plus the pristine non-coated (PRI NM) and a Cu salt (CuCl2), using the soil multispecies test system (samples at 28-56-84 days). Further, the species were tested individually, and Cu was measured in the test media (soil and soil solution) and organisms. There was a potential relationship with zeta potential, and toxicity of CuO NMs was as follows: -PEI (+28 mV) caused the least impact, -ASC and -CIT (-17 mV, -18 mV) the most, while PVP and PRI (-8 mV, -9 mV) caused an intermediate response. Differences were not explained by the contribution of soluble Cu. Coating interfered with the release of Cu2+ and/or the activation of copper regulators and detoxification mechanisms in the organisms, i.e. time to reach some kind of stability in organisms' uptake was shorter for -ASC and longer for -PVP during prolonged time. Thus, one of the main findings is that NMs hazard assessment requires long term testing to understand predicted effects across materials. Further, the coverage using a multispecies approach offers increased relevance and a more ecosystem qualified response.

Fragmentation of Valence and Carbon Core Excited and Ionized CH2FCF3 Molecule.

The photofragmentation dynamics of 1,1,1,2-tetrafluoroethane (R134a) with photon energies from 12 eV up to 320 eV, surrounding the C 1s edge is discussed. The ionic moieties were measured in coincidence with the ejected electrons (PEPICO mode), and detected as a function of the photon energy. Around the C K core edge, the fragmentation profiles are examined regarding the site specific excitation of the CH2FCF3 molecule. In the present case, site-selectivity is favored by the distinct chemical environments surrounding both C atoms. NEXAFS spectrum at the C 1s edge simulation has been obtained at the TDDFT level and excited state geometry optimization calculations have been performed at the inner-shell multiconfigurational self-consistent field level. Our observations indicate that the C(H2F) 1s excitation to a highly repulsive potential expels a fluorine atom leaving the heavier radical fragment C2F3H2* which relaxes to the fundamental state of the ion C2F3H2+. On the other hand, the excitation from the C(F3) 1s carbon to a repulsive state in the C-C bond, leads to a C-C bond cleavage, explaining the observed site specific fragmentation.

Multigenerational exposure of Folsomia candida to silver: Effect of different contamination scenarios (continuous versus pulsed and recovery).

Effects of pollutants are mostly assessed using standard testing procedures, which cover a fraction of the animals' life cycle. Although, in nature species are exposed during multiple generations of sub-lethal doses of persistent chemicals. In the present study, we focused on the multigenerational (MG) effects of silver in Folsomia candida during 6 generations using the EC50 for reproduction as exposure concentration. We tested 9 different exposure scenarios, going from continuous 6 generations Ag exposure over pulse exposure (i.e. one generation clean, next contaminated, next clean etc.) to gradually increasing the number of exposure generations, with a final transfer to clean media. The biological endpoints assessed included survival, reproduction and size, with reproduction being the most sensitive. The biological response depended on the specific MG scenario, e.g. the 6 Ag MG caused a decreased number of juveniles from F4, whereas the pulse exposure experienced an increase in reproductive output when in clean soil. It is uncertain whether Ag causes transgenerational effects, but the reproduction levels in both pulse exposures are lower than in continuous control over the 6 generations which could be due to transference of Ag by the maternal generation. Overall, population size distribution seemed to indicate a delay in time for egg laying, with close relationship between adult survival, organisms size and reproduction output. Size monitoring allowed significant added interpretation possibilities and we strongly recommend the addition of this endpoint to the standard guideline. The smaller observed size range can have implications in terms of adaptation potential, carrying associated increased risk.

Development and evaluation of accessories to improve the posture of veterinary surgeons in surgical procedures conducted in the field / Desenvolvimento e avaliação de acessórios para melhorar a postura de cirurgiões veterinários em procedimentos cirúrgicos realizados a campo

The study was conducted based on the information collected on rural properties in the state of Goiás, during practical classes of Surgical Clinic in Large Animals at the Veterinary Hospital of the Escola de Veterinária e Zootecnia of the Universidade Federal de Goiás and during the implementation of outreach projects developed by the institution. An acropostite-phimosis surgical procedure in the bulls in the field was selected, lasting over 30 minutes and requiring movements, posture and strength on the part of the surgeon. Devices were proposed and developed to provide improved comfort and safety to surgeons. The first device was a stool to be used by the professional during the execution of the surgical intervention. The use enabled the surgeon to sit down and rest their feet on the ground, reducing knee bending and distributing the support forces in various muscle groups. For the movement restriction of the surgeon, another accessory was developed to support the foreskin of the animal. Made of wood, this other device serves as a support for keeping the foreskin away from the ground and close to the surgeon. Its length, width and thickness established a good relation with the stool height, providing minimal discomfort to the professional. The third device was designed to assist in the immobilization of the animal and increase safety for the patient and surgical team. A fourth accessory was designed to protect the scapular region and avoid the occurrence of injuries in the radial nerve, myopathies and traumas during the rollover or prolonged stay of the animal in lateral decubitus. The choice of the shape, dimensions and softness of the device was mainly based on the weight of the animal. Such devices have proven to be effective, reducing the time of surgery, making cervical and lumbar movement easier, in addition to providing better support to the surgeon, reducing risks of musculoskeletal diseases.(AU)

O estudo foi realizado com base nas informações coletadas em propriedades rurais do estado de Goiás, durante aulas práticas de Clínica Cirúrgica de Grandes Animais no Hospital Veterinário da Escola de Veterinária e Zootecnia da Universidade Federal de Goiás e durante a execução de projetos de extensão desenvolvidos pela instituição. Foi selecionado um procedimento cirúrgico de acropostite-fimose em touros a campo, com duração acima de 30 minutos e com exigência de movimentos, postura e força por parte do cirurgião. Foram propostos e desenvolvidos dispositivos para proporcionar melhor conforto e segurança aos cirurgiões. O primeiro consistiu de um assento para ser usado pelo profissional durante a execução da intervenção cirúrgica. A utilização permitiu que o cirurgião sentasse e apoiasse os pés no chão, reduzindo a flexão dos joelhos e distribuindo as forças de apoio por diversos grupos musculares. Para a restrição de movimentação do cirurgião, outro acessório foi desenvolvido para apoiar o prepúcio do animal. Confeccionado em madeira, serve de suporte para mantê-lo distante do solo e próximo ao cirurgião. Seu comprimento, largura e espessura estabeleceram boa relação com a altura do assento, proporcionando o mínimo de desconforto ao profissional. O terceiro dispositivo foi confeccionado para auxiliar na imobilização do animal e aumentar a segurança para o paciente e para a equipe de cirurgia. Um quarto acessório foi desenvolvido para proteger a região escapular e evitar a ocorrência de lesões de nervo radial, miopatias e traumas durante o derrubamento ou a permanência prolongada do animal em decúbito lateral. A escolha do formato, das dimensões e da maciez do dispositivo fundamentou-se principalmente no peso do animal. Tais dispositivos mostraram-se efetivos, pois reduziram o tempo de cirurgia, facilitaram a movimentação cervical e a lombar, além de proporcionarem um melhor apoio do cirurgião e, assim, reduzirem riscos de doenças osteomusculares.(AU)

Echocardiographic features of the right heart in sleep-disordered breathing: the Framingham Heart Study.

The effect of sleep-disordered breathing (SDB) on right heart structure and function is controversial. Studies of patients referred for evaluation of possible sleep apnea have yielded conflicting results, and the impact of SDB on the right heart has not been investigated in the general population. We examined the echocardiographic features of subjects with SDB at the Framingham Heart Study site of the Sleep Heart Health Study. Of 1,001 polysomnography subjects, 90 with SDB defined as a respiratory disturbance index (RDI) score > 90th percentile (mean RDI = 42) were compared with 90 low-RDI subjects (mean RDI = 5) matched for age, sex, and body mass index. Right heart measurements, made without knowledge of clinical status, were compared between groups. The majority of the subjects were male (74%). After multivariable adjustment, right ventricle (RV) wall thickness was significantly greater (p = 0.005) in subjects with SDB (0.78 +/- 0.02 cm) than in the low-RDI subjects (0.68 +/- 0.02 cm). Right atrial dimensions, RV dimensions, and RV systolic function were not found to be significantly different between subjects with SDB and the low-RDI subjects. We conclude that in this community-based study of SDB and right heart echocardiographic features, RV wall thickness was increased in subjects with SDB. Whether the RV hypertrophy observed in persons with SDB is associated with increased morbidity and mortality remains unknown.

Echocardiographic examination of women previously treated with fenfluramine: long-term follow-up of a randomized, double-blind, placebo-controlled trial.

BACKGROUND: Fenfluramine hydrochloride was withdrawn from the market in September 1997 after reports of heart valve abnormalities in patients who used it. The prevalence of echocardiographic abnormalities and the clinical cardiovascular status of patients who received fenfluramine monotherapy remains uncertain. METHODS: A long-term, follow-up evaluation was undertaken in subjects who were randomly assigned to receive either fenfluramine hydrochloride (60 mg daily) or placebo as part of a double-blind smoking cessation therapy study. Cardiovascular status was evaluated by echocardiography, medical history, and physical examination. RESULTS: From the group of 720 smokers who had originally participated in the smoking cessation therapy trial, 619 women were enrolled; data from 530 (276 in the fenfluramine group and 254 in the placebo group) were evaluable. No statistically significant differences were identified in the prevalence of aortic or mitral regurgitation by Food and Drug Administration criteria or by grade, aortic or mitral valve leaflet mobility restriction or thickening, elevated pulmonary artery systolic pressure, or abnormal left ventricular ejection fraction. No significant differences were demonstrated in cardiovascular status by physical examination, and no serious cardiac events were noted among fenfluramine-treated subjects. CONCLUSION: There was no evidence of drug-related heart disease up to 4.9 years after anorexigen therapy in subjects who were randomly assigned to receive fenfluramine at the recommended dose for up to 3 months.

Noninvasive methods for detecting elevated left-sided cardiac filling pressure.

Knowledge of left-sided cardiac filling pressures has an important role in the management of patients with chronic heart failure. However, the use of a pulmonary artery catheter to measure pulmonary capillary wedge pressure is generally reserved for hospitalized patients with decompensated heart failure, leaving only noninvasive means of estimating left heart pressures in the majority of patients. Unfortunately, the routine clinical evaluation of patients with chronic systolic heart failure lacks the sensitivity and specificity needed to accurately assess left atrial pressure. In this review, we focus on noninvasive methods that can reliably predict left-sided filling pressures and may have clinical application in the ambulatory setting.

Immediate effect of aortic valve replacement for aortic stenosis on left ventricular diastolic chamber stiffness.

Diastolic dysfunction is common after coronary artery bypass surgery, and we hypothesized that left ventricular (LV) hypertrophy associated with aortic stenosis may lead to worsening LV diastolic function after aortic valve replacement for aortic stenosis. Transesophageal echocardiographic LV images and simultaneous pulmonary arterial wedge pressures were used to define the LV diastolic pressure cross-sectional area relation before and immediately after aortic valve replacement for aortic stenosis in 14 patients. In all patients, LV diastolic chamber stiffness increased, as evidenced by a leftward shift in the LV diastolic pressure cross-sectional area relation. At comparable LV filling (pulmonary arterial wedge) pressures the mean LV end-diastolic cross-sectional area preoperatively was 17.9 +/- 1.7 cm2, but decreased by 32% after aortic valve replacement to 12.1 +/- 1.2 cm2 (p = 0.0001). In conclusion, after aortic valve replacement, diastolic chamber stiffness increased in all patients.

Ventricular remodeling in active myocarditis. Myocarditis Treatment Trial.

BACKGROUND: Remodeling of the left ventricle with the development of a spherical cavity occurs in dilated cardiomyopathy and is associated with a poor long-term prognosis. The early effects of myocarditis on left ventricular geometry have not been previously described or correlated with clinical outcome. METHODS: The baseline echocardiograms of 35 patients with biopsy-confirmed myocarditis were compared with 20 normal controls. Left ventricular end-diastolic volume, long axis length, and mid-cavity diameter were measured. The degree of sphericity was expressed as the ratio of the mid-cavity diameter to the long axis length. Left ventricular ejection fraction was assessed by radionuclide angiography. RESULTS: In patients with myocarditis, mean left ventricular volume of 81 +/- 29 mL/m(2) was significantly greater than 50 +/- 8 mL/m(2) in controls (P =.001). Chamber dilatation occurred primarily along the mid-cavity diameter, which measured 5.3 +/- 0.8 cm in patients with myocarditis versus 4.2 +/- 0.4 cm in controls (P =.001). The degree of left ventricular sphericity in patients with myocarditis, 0.64 +/- 0.08, was significantly greater than that of controls, 0.54 +/- 0.04 (P =.001). When patients were stratified according to left ventricular volume, patients with increased left ventricular volume (>75 mL/m(2)) were associated with a more spherical chamber and lower left ventricular ejection fraction than patients with a more normal left ventricular volume (

Congestive heart failure in patients with coronary artery disease: the gender paradox.

To determine whether the increased prevalence of congestive heart failure in women compared with men undergoing diagnostic cardiac catheterization is the result of a difference in the left ventricular pressure/volume relation, we retrospectively compared the clinical characteristics, left ventricular ejection fraction, and end-diastolic pressure and volume in 586 women and 1081 men undergoing diagnostic coronary angiography and left ventriculography. In comparison with men, women were older (63 vs 60 years; p = 0.0001) and had more hypertension (41% vs 31%; p = 0.0001), diabetes (18% vs 12%; p = 0.003), and symptoms of congestive heart failure (13% vs 10%; p = 0.05). In spite of this, women had a better mean left ventricular ejection fraction (61% vs 56%; p = 0.0001) and less prevalent three-vessel disease (23% vs 34%; p = 0.0001). Left ventricular end-diastolic volume index was smaller in women compared with men (73 vs 79 ml/m2; p = 0.0001) in spite of having similar left ventricular end-diastolic pressure. When patients were stratified according to left ventricular end-diastolic pressure, women had a significantly smaller end-diastolic volume than men did when left ventricular end-diastolic pressure was > or = 18 mm Hg (74 vs 86 ml/m2; p = 0.0001). In a multivariate analysis, female sex remained an independent predictor of congestive heart failure (odds ratio 1.72, 95% confidence interval 1.11 to 2.66, p = 0.02). This study suggests that diastolic dysfunction is one mechanism for the paradox of more frequent heart failure symptoms in spite of better preserved left ventricular systolic function in women. Sex appears to influence the pattern of myocardial dysfunction in patients with known or suspected coronary artery disease, but the basis for this observation remains speculative.

Right ventricular dilation in primary amyloidosis: an independent predictor of survival.

This study was designed to characterize the geometry and function of the right ventricle and its prognostic significance in patients with primary (AL) cardiac amyloidosis. AL amyloidosis is an infiltrative systemic disease that can result in thickening of heart structures and rapidly progressive congestive heart failure due to restrictive ventricular physiology and eventual systolic dysfunction. Thirty-seven patients with AL amyloid heart involvement and 20 normal control subjects were evaluated using 2-dimensional and Doppler echocardiography. Based on the ratio of left-to-right end-diastolic ventricular chamber areas, patients were classified into 2 groups: 25 patients with disproportionate right ventricular (RV) dilation (left ventricular to RV ratio < or = 2) and 12 with a ventricular area ratio > 2. Patients with a relatively dilated right ventricle (ratio < or = 2) had a shorter median survival (4 months) compared with patients with an area ratio > 2 (10 months, p <0.003). Of multiple clinical, echocardiographic, and Doppler features entered into a multifactorial model, a ventricular area ratio < or = 2 remained the only independent predictor of survival. Patients with AL amyloid heart disease represent a heterogeneous population with regard to both prognosis and the relative degree of right to left ventricular dilation. RV dilation in patients with amyloid heart disease appears to be associated with more severe involvement and is associated with a very poor prognosis with a median survival of only 4 months.

Right coronary artery stenosis: an independent predictor of atrial fibrillation after coronary artery bypass surgery.

OBJECTIVES: This study attempted to determine the importance of severe proximal right coronary artery disease as a predictor of atrial fibrillation in patients after coronary artery bypass surgery. BACKGROUND: Studies in patients undergoing noncardiac surgery have suggested that ischemia in the right coronary artery distribution is associated with a high incidence of atrial fibrillation. However, the importance of right coronary artery disease as a predictor of atrial fibrillation after bypass surgery is unknown. METHODS: The occurrence of sustained postoperative atrial fibrillation was studied prospectively in 168 consecutive patients undergoing coronary artery bypass grafting. Patients were followed up postoperatively until discharge. Severe right coronary artery stenosis was defined as > or = 70% lumen narrowing. RESULTS: Of 104 patients with proximal or mid right coronary artery stenosis, 45 (43%) had atrial fibrillation postoperatively compared with 12 (19%) of the 64 patients without significant right coronary disease (p = 0.001). Univariate predictors of atrial fibrillation included right coronary artery stenosis (p = 0.001), advancing age (p = 0.0001) and lack of beta-adrenergic blocking agent therapy after bypass surgery (p = 0.0004). Multivariate adjusted risk of developing atrial fibrillation after bypass surgery increased with the presence of severe right coronary artery disease (odds ratio 3.69, 95% confidence interval [CI] 1.61 to 8.48), advancing age (odds ratio 2.24/10 years, CI 1.48 to 3.41) and male gender (odds ratio 2.36, CI 1.01 to 5.49). The use of beta-blockers postoperatively was associated with a protective effect (odds ratio 0.4, CI 0.17 to 0.80). CONCLUSIONS: The presence of severe right coronary artery stenosis is an independent and powerful predictor of atrial fibrillation after coronary artery bypass surgery. In association with age, gender and postoperative beta-blocker therapy, these variables can be used to identify patients at increased risk for developing this arrhythmia.

Increased left ventricular diastolic chamber stiffness immediately after coronary artery bypass surgery.

OBJECTIVES: The aim of this study was to assess the incidence and severity of left ventricular diastolic dysfunction immediately after coronary artery bypass surgery by utilizing simultaneous transesophageal echocardiographic and hemodynamic monitoring. BACKGROUND: Left ventricular diastolic dysfunction has been documented after coronary bypass surgery, but its measurement has been technically difficult to acquire and limited by dependence on loading conditions. METHODS: End-diastolic pressure-area curves were constructed before and immediately after coronary bypass surgery in 20 patients. Transesophageal echocardiographic images at the midpapillary level of the left ventricle and hemodynamic data were recorded. Volume status was manipulated to alter loading conditions, and multiple measurements were taken at each loading condition. RESULTS: Diastolic function worsened in all patients, as manifested by a postoperative leftward shift of the end-diastolic pressure-area curve. At a comparable preload, mean end-diastolic area +/- SEM decreased by 15% from 17.6 +/- 0.8 to 14.9 +/- 0.8 cm2 postoperatively (p = 0.0001). CONCLUSIONS: Left ventricular diastolic chamber stiffness frequently increases immediately after coronary artery bypass surgery. Simultaneous hemodynamic and transesophageal echocardiographic monitoring, through the construction of end-diastolic pressure-area curves, is a useful method to evaluate diastolic function and guide management after cardiac surgery.

Right ventricular dysfunction: an independent predictor of adverse outcome in patients with myocarditis.

To assess the predictive value of right ventricular systolic function in patients with active myocarditis, the echocardiograms of 23 patients with biopsy-confirmed myocarditis were reviewed. Right ventricular systolic function was evaluated qualitatively and quantitatively by descent of the right ventricular base. Patients were divided into those with normal right ventricular function, in whom right ventricular descent was 1.9 +/- 0.1 cm, and those with abnormal right ventricular function, in whom right ventricular descent was 0.8 +/- 0.1 cm (p < 0.001). There were no differences between the two groups in age, duration of symptoms, baseline hemodynamics, or histologic assessment. Initial left ventricular ejection fraction was significantly lower in patients with depressed right ventricular function (27.5 +/- 4.9%) compared with that in patients with normal right ventricular function (47.5 +/- 6.3%) (p = 0.01). The likelihood of an adverse outcome, defined as death or need for cardiac transplantation, was greater in patients with abnormal right ventricular function (right ventricular descent < or = 1.7 cm) than in patients with normal right ventricular function (right ventricular descent > 1.7 cm) (p < 0.03). Multivariate analysis revealed that right ventricular dysfunction as quantified by right ventricular descent was the most powerful predictor of adverse outcome.

Right ventricular thrombus: an unusual manifestation of Behçet's disease.

Behcet's disease is a chronic multisystem illness in which cardiac involvement is a rare manifestation. In this unusual case a young man had symptoms that primarily related to recurrent right ventricular thrombi and pulmonary thromboemboli. Transesophageal echocardiography was useful in documenting the presence of intracardiac thrombus and establishing the diagnosis.