Impact of cardiovascular risk factors on incidence and severity of Retinal Vein Occlusion.

PURPOSE: Retinal Vein Occlusion (RVO) is a thrombotic process affecting retinal veins. The purpose of this research is to study demographic characteristics and prevalence of cardiovascular comorbidities among subjects affected by RVO. In addition, authors explore the role of each variable in determining occlusion type and severity. SUBJECTS, MATERIALS AND METHODS: This was a prospective observational study recruiting subjects affected by RVO and secondary macular edema. Exclusion criteria included pre-existing macular edema, recent ocular surgery (<6 months), pregnancy, diagnosis other than RVO, diabetes mellitus type I, any systemic pathology that significantly reduced life expectancy. Each participant was studied through a comprehensive medical history, cardiovascular assessment, blood testing, ocular exam, and macular OCT imaging. RESULTS: A total of 145 eyes, 145 participants, thereof 80 males (55%) and 65 females. (45%) Mean age: 62.5 ± 14.3 SD. 61 eyes (42%) were affected by CRVO and 84 eyes (58%) by BRVO. No statistically significant differences were noted between genders. Hypertension was very prevalent (63%). Dyslipidemia was more associated with BRVO (p = 0.044). Subjects with hypertension had a mean central macular thickness (CMT) of 643 µm against a mean of 489 µm of those without hypertension. (p < 0.05). No other variable was associated with macular edema severity. CONCLUSIONS: Older age and hypertension are strong risk factors for RVO. Dyslipidemia was strongly associated with BRVO. (p=0.044) Hypertension was not only associated with RVO incidence, but also with its severity. In fact, hypertensive subjects had significantly worse macular edema.

Ocular hypertension management in long-term treatments with intravitreal dexamethasone implants: a 3-year experience.

PURPOSE: A commonly recognized complication of intravitreal steroids is ocular hypertension (OHT).The aim of this study was to investigate the effectiveness of pharmacotherapy in controlling this side effect, even in patients receiving sequential injections. METHODS: A total of 146 injections were performed on 78 patients over 3 years. 78 eyes were treated with 1 injection, 44 eyes were treated with 2 injections; 24 eyes were treated with 3 injections. The intravitreal corticosteroid used in this observational study is 0.7mg dexamethasone, commercially known as 0.7mg Ozurdex®. RESULTS: Following the first injection, mean intraocular pressure (IOP) increased by 1,90 mmHg. Following the second injection, mean IOP increased by 0.23 mmHg. Following the third injection, there was no statistically significant change. Patients with IOP >= 21mmHg (7% of all participants) were started on topical pressure-lowering medications. CONCLUSIONS: Intravitreal dexamethasone implants increased IOP of variable degrees in different patients. However, secondary OHT was effectively controlled with pharmacotherapy alone. This allowed for continuation of dexamethasone therapy.

Preparation of small size palladium nanoparticles by picosecond laser ablation and control of metal concentration in the colloid.

We assessed a method for the preparation of small, highly stable and unprotected Pd nanoparticles by picosecond laser ablation in 2-propanol. The nanoparticles can be extracted from 2-propanol by centrifugation and redispersed in water, where a strongly negative ζ-potential assures long term stability. The proposed procedure permits reduction of particle size down to 1.6nm and optimization of the Pd(0):Pd(II) ratio which, in the best cases, was of the order of 6:1. The increase of this ratio with ablation times has been correlated to the high temperature conversion of PdO to metallic Pd by a simple theoretical model. A study of the relationship between colloid absorption at 400nm and Pd concentration permitted the role of PdO in the determination of the UV-vis spectra to be clarified and the limits of the Mie theory for the evaluation of colloid concentration to be established. The absorption at 400nm can be used as a fast method to estimate the Pd content in the colloids, provided that a calibration of the ablation process is preliminarily performed.

Cutaneous Adverse Reactions to Highly Antiretroviral Therapy in HIV-Positive Patients.

Adverse drug reactions to highly antiretroviral therapy (HAART) are major obstacles in its success. Although overall mortality from HIV has dramatically declined owing to HAART, these antiretroviral regimens have been associated with a wide spectrum of severe cutaneous reactions. The severity of cutaneous adverse reactions varies greatly, and some may be difficult to manage. To optimize adherence and efficacy of antiretroviral treatment, clinicians must focus on preventing adverse effects whenever possible, and distinguish those that are self-limited from those that are potentially serious. This paper presents the case of a serious cutaneous adverse reaction to Atripla in a HIV-positive 50-year-old Caucasian woman.

Achilles tendon ultrasonography may detect early features of psoriatic arthropathy in patients with cutaneous psoriasis.

BACKGROUND: Psoriatic arthropathy is a progressive and debilitating disease involving reduction of functional activity of the articulations with consequent deterioration of the patient's quality of life. The entheses represent the initial site of articular inflammation and the enthesis of the Achilles tendon is the first to be affected. In some patients with psoriasis, enthesitis may not be diagnosed because it is still asymptomatic. OBJECTIVES: To evaluate whether ultrasonography allows early diagnosis in a larger population and to identify significant alterations of enthesitis beyond increased thickness of the Achilles tendon. MATERIALS AND METHODS: The study was undertaken on 59 patients (16 women, 43 men), with chronic plaque psoriasis and 59 patients with other dermopathies. The patients underwent echographic evaluation of the Achilles heel using a Voluson imaging system. The severity of the psoriasis was evaluated by the Psoriasis Area Severity Index and the enthesitis by the Glasgow Ultrasound Enthesitis Scoring System (GUESS). RESULTS: The GUESS score was higher in those patients with psoriasis compared with patients with other dermopathies. Among psoriatic patients, 22% (13 of 59) presented tendon thickness over 5·29 mm and irregular tendon structure. Other abnormalities affected the tendon in 12 patients. In seven patients (12%) bursitis was also revealed. CONCLUSIONS: Our data confirm that ultrasonography is a sensitive technique which reveals enthesitis more frequently than clinical examination in patients affected by psoriasis. We suggest the use of ultrasonography of the Achilles tendon in early diagnosis of psoriatic arthropathy with the objective of preventing progression of the pathology.

Multiple cutaneous metastases in the chest from prostatic carcinoma.

We report a case of multiple cutaneous metastases from prostate cancer. A 78-year-old man with an 8-year history of prostate cancer had multiple nodular lesions in the chest. Histologically, the lesion showed an abortive glandular lumina and tall columnar cells with abundant cytoplasm. Immunohistochemical staining for AE1:AE3 cytokeratin cocktail, prostate-specific antigen, and prostate-specific acid phosphatase was positive in tumor cells, confirming the diagnosis of cutaneous metastases from prostate cancer. We report this case because of the rarity of cutaneous metastases from prostatic adenocarcinoma in the chest region.

Hybrid composites made of multiwalled carbon nanotubes functionalized with Fe3O4 nanoparticles for tissue engineering applications.

A straightforward technique for functionalization of multiwalled carbon nanotubes (MWCNTs) with magnetite (Fe(3)O(4)) nanoparticles was developed. Iron oxide nanoparticles were deposited on MWCNT surfaces by a deposition-precipitation method using Fe(3+)/Fe(2+) salts precursors in basic solution. The characterizations by HRTEM, XRD, SEM/EDX, AAS and TPR analyses confirmed the successful formation of magnetic iron oxide nanoparticles on the MWCNT surface. Fe(3)O(4)/MWCNT hybrid composites were analysed in vitro by incubation with mesenchymal stem cells for 1, 3 and 7 days, either in the presence or absence of a static magnetic field. Analysis of cell proliferation was performed by the MTT assay, quantification of cellular stress was performed by the Lactate Dehydrogenase assay and analysis of cell morphology was performed by actin immunofluorescence and scanning electron microscopy. Results demonstrate that the introduction of magnetite into the MWCNT structure increases biocompatibility of oxidized MWCNTs. In addition, the presence of a static magnetic field further increases Fe(3)O(4)/MWCNT influence on cell behaviour. These results demonstrate this novel Fe(3)O(4)/MWCNT hybrid composite has good potential for tissue engineering applications.

Coumarin-conjugated multiwalled carbon nanotubes for potential biological applications: development and characterization.

This work presents a novel cascade of chemical functionalization of multiwalled carbon nanotubes which allows the conjugation with differently substituted coumarins. Aim of the present work is to synthesize new materials able to rescue cells from the adverse effect of CNT particles since pristine CNTs are practically insoluble and tend to accumulate inside cells, organs and tissues. Moreover, it was reported that single walled CNTs particles show an adverse effect on keratinocytes through an oxidative mechanism, leading to NF-kB activation. The conjugation with coumarins, known superoxide anion scavengers, could switch the cytotoxicity of the new materials. The cascade functionalization of MWCNTs by sequential steps of carboxylation, acylation, amine modification and finally, coumarin conjugation have been performed and the synthesis and the chemical properties of several f-MWCNTs-coumarins have been exploited.

Morphological modification of MWCNT functionalized with HNO3/H2SO4 mixtures.

The acidic oxidation with HNO3/H2SO4 mixtures is widely reported as an effective method to functionalize multi-walled carbon nanotubes (MWCNT). Although effective, a bad control of the oxidation conditions frequently cause serious modifications of carbon nanotube network, limiting further potential applications. Investigations about the effect of functionalization operating conditions on the morphological, chemical and chemical-physical properties of MWCNT can be useful for a proper setting of oxidation reactions of MWCNT according to their specific applications. In this work the effect of HNO3/H2SO4 ratio on the morphological and chemical-physical properties and on the degree of functionalization of MWCNT was investigated. Electron microscopy, thermogravimetric, X-ray diffraction, titration and water dispersion analyses clearly revealed that the increase of the amount of concentrated sulphuric acid in the HNO3/H2SO4 mixture lead to an increase of the amount of functional groups on the MWCNT surface but also to an increase of structural damage in terms of tube cutting and generation of additional defects in the graphitic network of pristine

Scaling laws for multi-walled carbon nanotube growth by catalyzed chemical vapor deposition.

The synthesis of C nanotubes by catalyzed chemical vapor deposition at 600 degrees C is investigated, using yield and purity degree of C deposits to monitor the reaction outcome. From the reaction, carried out in C4H10-H2-He environment over Al2O3 supported Fe catalysts, multi-walled C nanotubes are attained, which, after purification, are analyzed by routinely-used diagnostics techniques. In order to clarify the role of the growth parameters, various experiments are performed changing flow rates of reactive gases, as well as, amount, metal load and reduction temperature of Fe/Al2O3 catalysts in the ranges 15-90 cc/min, 0.25-2.00 g, 10-40 wt% and 500-700 degrees C, respectively. Correspondingly, carbon yield varies between 47 wt% and 913 wt%, while purity degree between 56 wt% and 93 wt%. Owing to the lack of any correlation between these changes, it is initially quite difficult to envisage the effect, produced by any change of the growth conditions, on the final reaction outcome. The problem is solved by applying a semi-empirical approach, through which the "original" growth variables are combined to give dimensionless arguments (scaling laws for the reaction parameters), able to account for all the variation of yield and purity in the ranges considered. As final result, the growth issue can be easily predicted because carbon yield and purity degree can be approximated through very simple functions of the "new" process variables.

Influence of carbon source and Fe-catalyst support on the growth of multi-walled carbon nanotubes.

Catalytic activity of iron based catalysts in the production of multi-walled carbon nanotubes (MWCNTs) has been investigated. The effect of the carbon source (ethane or isobutane), catalyst support (Al2O3 or SiO2), iron loading, catalyst reduction temperature and reaction temperature on yield and quality of carbon products has been examined. The structural and morphological properties of catalyst and carbon products obtained have been analyzed by means of scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy (RS), thermogravimetric analysis (TGA) and X-ray powder diffraction (XRD). The iron-based catalysts supported on alumina seem to be efficient systems for the production of carbon nanotubes from chemical vapor deposition (CVD) of isobutane with very interesting yields. The opportune calibration of reaction parameters, such as iron loading and reaction temperature, can in fact drive the synthesis toward the formation of high quality CNTs.

Effects of zafirlukast on bronchial asthma and allergic rhinitis.

Asthma and allergic rhinitis are common conditions, occurring with increasing prevalence and frequently coexist. In both conditions histamine and cysteinil leukotrienes are important pathogenic inflammatory mediators. We evaluated the effects of the leukotriene receptor antagonist zafirlukast, 20mg administered twice daily for 2 weeks, in patients with allergic rhinitis and bronchial asthma during the grass pollen season. Patients underwent skin prick testing, spirometry, rhinomanometry, mucus transport test with saccharine, nasal epithelial brushing to study ciliary beat and, finally, nasal lavage.Thirty-five subjects completed the study. At the end of the study period, zafirlukast significantly reduced asthma and rhinitis symptoms (P< or =0.05); FEV(1) values were unchanged (P=0.10), whereas nasal resistances showed a decrease following treatment (P=0.01). Ciliary beat frequency (CBF) also improved (P=0.00), although mucociliary transport showed no improvement (P=0.87). The number of eosinophils in nasal lavage fluid decreased (P=0.00) while that of neutrophils was unchanged (P=0.09). These positive effects suggest that zafirlukast may be usefully employed in the treatment of both bronchial asthma, as previously demonstrated, and allergic rhinitis.

Oxidative modification of proteins in chronic alcoholics.

Oxidative modification of proteins is of great importance because of their biological role in transport, enzyme activity, immune response and membrane fluidity. This study investigated the redox status of proteins in plasma, erythrocyte and erythrocyte ghosts of chronic alcoholics; a comparison with subjects affected by chronic viral hepatitis and healthy controls was also performed. Compared to the other groups, chronic active alcoholics showed significant increase of plasma, erythrocyte and erythrocyte ghost concentrations of carbonyl proteins, marker of protein oxidative damage. Also, a significant correlation was noted between daily alcohol intake and plasma levels of carbonyl proteins. The incubation of fresh human plasma with acetaldehyde, but not with ethanol, led to a significant increase of the carbonyl protein production. In conclusion, plasma, erythrocyte and membrane proteins are oxidatively modified in active chronic alcoholics; these changes seem to be related to acetaldehyde rather than ethanol toxicity.

Pressor effects from daily events and laboratory complex stimuli relating personality factors.

Our preliminary research has attempted to establish a series of methods to study the complex interactions occurring between pressor reactivity and personality profile. Ten untreated mild hypertensives (age 42.9 +/- 8) without damaged target organs were recruited from an outpatient hypertension center along with an equal number of normotensive volunteers (age 38.2 +/- 8.1). We performed a sequence of stressor types under laboratory conditions (sensory perceptual activities, psychomotor responses, and cognitive behavior) following an order ranging from inferior levels to superior levels of systemic integration. The subjects also underwent a 24-h automatic noninvasive blood pressure recording which took into account the situational reactivity. They filled in MMPI and STAI questionnaires before and after the stressor batteries. Only the sensory-perceptual test (Stroop color test modified), the arithmetic test, and the psychomotor test provoked a significant increase in blood pressure and, in the latter test, also a significant increase of the heart rate. The test batteries' mean differences were not significant between the two groups. Similarly, the answers to the trait-anxiety questionnaires did not allow us to make a substantial division between normotensive and hypertensive subjects. On the contrary, the situational anxiety questionnaires showed a significant difference in the score reading preceding and following a task performed by the hypertensive subjects. We observed significant differences for both systolic and diastolic 24-h blood pressure data in transition from a working situation to the sleeping period. However, there was not a significant difference in hypertensive blood pressure readings recorded during work and at home.(ABSTRACT TRUNCATED AT 250 WORDS)

[Copper and nervous system. An experimental study (author's transl)]. / Cuivre et système nerveux. Etude expérimentale.

Sodium azide is known to produce alterations in mammalian copper proteins, thus rendering them unable to bind exogenous metal, which remains in the "labile pool" condition. Continuous administration of sodium azide at LD50 for 30 days causes copper accumulation in several tissues and even in the nervous system, with characteristic changes in neurones and glial cells, very much resembling the alterations observed in Wilson's disease. Dietary copper administration, on the contrary, though raising the level of tissue-bound metal, does not produce cellular damage. These findings allow us to suppose that sodium azide may alterate the coppper chelating proteins in the tissues, especially in the nervous system, thus causing the storage of cell-toxic "labile pool" metal. The pathogenesis of Wilson's disease and the problem of "pathoclisis" in the nervous system are debated.