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Ocular toxoplasmosis is the major cause of infectious posterior uveitis worldwide, inducing visual field defect and/or blindness. Despite the severity of this disease, an effective treatment is still lacking. In this study, spiramycin-loaded PLGA implants were developed aiming at the treatment of ocular toxoplasmosis. Implants were manufactured by a hot-molding technique, characterized by Fourier Transform Infrared Spectroscopy, X-Ray Diffraction, Differential Scanning Calorimetry, Scanning Electron Microscopy; evaluated in terms of ocular biocompatibility by immunofluorescence, flow cytometry, cell migration, Hen's egg test-chorioallantoic membrane (HET-CAM) irritation test; and investigated in terms ofin vitroefficacy againstToxoplasma gondii. Characterization techniques indicated that spiramycin was dispersed into the polymeric chains and both substances preserved their physical structures in implants. The HET-CAM test indicated that implants did not induce hemorrhage or coagulation, being non-irritant to the CAM. ARPE-19 cells showed viability by MTT assay, and normality in cell cycle kinetics and morphology, without stimulating cell death by apoptosis. Finally, they were highly effective against intracellular parasites without inducing human retinal pigment epithelial cell death. In conclusion, spiramycin-loaded PLGA implants represent a promising therapeutic alternative for the local treatment of ocular toxoplasmosis.

Background: All guidelines for DBS in Parkinson’s disease (PD) include a contraindication for ‘dementia’. It is unclear where this cut-off should occur and if patients with mild cognitive impairment (MCI) do not do as well. This prospective cohort analysis assessed if pre-operative cognition affected post-operative quality of life. Methods: PD patients receiving bilateral STN-DBS (n=100) were prospectively studied using STROBE guidelines. All had Montreal Cognitive Assessment (MoCA), motor (UPDRS), mood (BDI-II), and quality of life (Parkinson Disease Questionnaire summary index, PDQ-39-SI). Two cohorts, pre-operative MCI (MoCA:18-25) and normal cognition (MoCA:26-30), had post-operative PDQ-39-SI at 1-year. The primary outcome was the proportion of patients with an improved PDQ-39-SI at 1-year. Results: Cohorts were not significantly different in age, severity of illness, response to dopamine, or mood. MCI was present in 27/100. Improved quality of life at 1-year occurred in 75% with normal cognition and 70% with MCI (p=0.54) with RR=1.1 (95% CI, 0.8-1.5). Linear regression analysis showed no correlation between pre-operative cognition and post-operative outcome (R2=0.02). Conclusions: Parkinson’s patients with MCI should be offered DBS if their motor symptoms require surgery. Guidelines for DBS surgery in PD should change from “dementia is contraindicated” to “patients require adequate cognitive functioning, MoCA greater than equal to 18.”

This study aimed to evaluate in vitro and in vivo trypanocidal activity of free and nanoencapsulated curcumin against Trypanosoma evansi. In vitro efficacy of free curcumin (CURC) and curcumin-loaded in lipid-core nanocapsules (C-LNCs) was evaluated to verify their lethal effect on T. evansi. To perform the in vivo tests, T. evansi-infected animals were treated with CURC (10 and 100 mg kg−1, intraperitoneally [i.p.]) and C-LNCs (10 mg kg−1, i.p.) during 6 days, with the results showing that these treatments significantly attenuated the parasitaemia. Infected untreated rats showed protein peroxidation and an increase of nitrites/nitrates, whereas animals treated with curcumin showed a reduction on these variables. As a result, the activity of antioxidant enzymes (superoxide dismutase and catalase) differs between groups (P<0·05). Infected animals and treated with CURC exhibited a reduction in the levels of alanine aminotransferase and creatinine, when compared with the positive control group. The use of curcumin in vitro resulted in a better parasitaemia control, an antioxidant activity and a protective effect on liver and kidney functions of T. evansi-infected adult male Wistar rats. [ABSTRACT FROM PUBLISHER]

The use of long-period gratings (LPGs) to distribute optical power from one core to all the cores in a multicore fiber (MCF) is theoretically analyzed. Simple analytical expressions that describe the mode power’s evolution along the LPGs are derived from the coupled mode equations. This study demonstrated the power transfer between cores in a MCF promoted by identical LPGs. Moreover, with this technique, the pump signal can be distributed to all the cores without interfering with the transmission signals.

The authors present a clinical case of a 35-year-old patient who was diagnosed with intercostal artery-to-pulmonary artery fistula and review the literature of systemic-to-pulmonary fistulae based on radiological findings of an exceptional case report.

We consider an approach to the Brans-Dicke theory of gravity in which the scalar field has a geometrical nature. By postulating the Palatini variation, we find out that the role played by the scalar field consists in turning the space-time geometry into a Weyl integrable manifold. This procedure leads to a scalar-tensor theory that differs from the original Brans-Dicke theory in many aspects and presents some new features. [ABSTRACT FROM AUTHOR]

The description of the Casimir effect via the conventional light front frame gives the result that no finite Casimir energy density exists when the boundary conditions are related to the unphysical situation where the boundaries move at the speed of light. In the present paper, we investigate if the consideration of the oblique light front coordinates, more convenient for studies in thermal light front quantum field theories, can also be used to describe in a physically consistent manner the Casimir effect in the light front dynamics. Using these coordinates, we show that the correct prescription in the light front formalism to recover the standard Casimir effect involves two aspects: the presence of boundaries that are not at the speed of light and that impose conditions to the field taken at the same Minkowski time. [ABSTRACT FROM AUTHOR]

Liposomes, usually assembled from organic/synthetic lipidic compounds, are biocompatible, biodegradable, non-toxic, and do not induce immune response. Due to their structural versatility in terms of size, composition, surface charge, bilayer fluidity and ability to encapsulate drugs regardless of their solubility, liposomes enable the production of a vast number and type of formulations with potential clinical use. They can be administered through several routes of administration (e.g. i.v., i.m., oral, nasal, etc.). The use of liposomes enables the variation and control retention of drugs in biologic fluids, enhancing blood circulation and specific compartments residence. They can be tailored to target specific tissues and cells. They can play a very important role for imaging diagnosis and/or therapy. After an extensive literature review of the subject, we selected a particular area of potential clinical application: pulmonary oedema. This clinical entity has a variety of possible etiologies, conducing to two main types of edema: cardiogenic and non-cardiogenic. At the moment a dedicated technique for the early diagnosis/therapy of this pathology is lacking. We propose a new methodology using a specially designed GUV formulation, encapsulating chosen radiotracers labeled with 99mTc. The aim of the work has been successfully achieved in an experimental animal model of cardiogenic pulmonary oedema. Experiments using an animal model of non-cardiogenic pulmonary oedema are in course (simultaneous study with two different drugs), using the same GUV methodology. Preliminary results are very promising.

In addition to the classical neurotransmitters, acetylcholine and noradrenaline, a wide number of peptides with neurotransmitter activity have been identified in the past few years. Among them, the tachykinins substance P (SP), neurokinin A (NKA) and neurokinin B (NKB) appear to act as mediators of nonadrenergic, noncholinergic (NANC) excitatory neurotransmission. Tachykinins interact with specific membrane proteins, belonging to the family of G protein-coupling cell membrane receptors. Until now, three tachykinin receptors termed NK1 (NK1R), NK2 (NK2R) and NK3 (NK3R) have been cloned in different species. A large amount of reports suggests that these peptides are involved in nociception and neuroimmunomodulation, and in the development of different diseases such as bronchial asthma, inflammatory bowel syndrome and psychiatric disorders. Tachykinin receptor antagonists are therefore promising, therapeutically relevant agents. However, and in spite of extensive research, the obtention of selective antagonists of tachykinin receptors have revealed very difficult. An understanding of how ligands interact with their receptors is essential to permit a rational design of compounds acting selectively at the tachykinin receptor level. The major aim of the present article is to review the structure-activity data that exist for tachykinins and their receptors, with the purpose of getting insight into basic structural requirements that determine ligand / receptor interaction.

This paper presents a brief overview of motor technologies and the main results of the characterisation of electricity use in Central and Eastern European countries, as well as the results of the assessment of carbon and electricity savings potential of energy efficient motor technologies in this field. Because this sector is scattered over many countries and because it was quite difficult to obtain accurate information on motor electricity use, only the main countries have been subject to this evaluation. The countries included in the study were Bulgaria, the Czech Republic, Hungary, Poland, Romania, Russia, Slovakia and Ukraine.

In this paper, we assess the design and performances of a strictly non-blocking all-optical cross-connect demonstrator node for WDM wavelength path networks. The all-optical cross-connect (AOXC) prototype was experimentally tested in a small 2 x 2 WDM network with a STM-16 bit stream per channel. The single and cascaded performance of the AOXC was also simulated and its results were validated with the experimental ones.

First results on the investigation of the tensile load stress - elastic strain response of an AlSi-metal matrix composites are presented. Measurements were performed at room temperature and in-situ at elevated temperature using white high-energy synchrotron radiation. The experiments show the evolution of the lattice plane dependent microstrains in the aluminium matrix and the silicon particles.

Background:All guidelines for DBS in Parkinson’s disease (PD) include a contraindication for ‘dementia’. It is unclear where this cut-off should occur and if patients with mild cognitive impairment (MCI) do not do as well. This prospective cohort analysis assessed if pre-operative cognition affected post-operative quality of life. Methods:PD patients receiving bilateral STN-DBS (n=100) were prospectively studied using STROBE guidelines. All had Montreal Cognitive Assessment (MoCA), motor (UPDRS), mood (BDI-II), and quality of life (Parkinson Disease Questionnaire summary index, PDQ-39-SI). Two cohorts, pre-operative MCI (MoCA:18-25) and normal cognition (MoCA:26-30), had post-operative PDQ-39-SI at 1-year. The primary outcome was the proportion of patients with an improved PDQ-39-SI at 1-year. Results:Cohorts were not significantly different in age, severity of illness, response to dopamine, or mood. MCI was present in 27/100. Improved quality of life at 1-year occurred in 75% with normal cognition and 70% with MCI (p=0.54) with RR=1.1 (95% CI, 0.8-1.5). Linear regression analysis showed no correlation between pre-operative cognition and post-operative outcome (R2=0.02). Conclusions:Parkinson’s patients with MCI should be offered DBS if their motor symptoms require surgery. Guidelines for DBS surgery in PD should change from “dementia is contraindicated” to “patients require adequate cognitive functioning, MoCA318”.

ß-radiation detected nuclear magnetic resonance (ß-NMR) measurements of12B occupying sites with noncubic surroundings after implantation into Si have been extended from p-type to moderately doped n-type material. The quadrupole split signals observed in both materials indicate the existence of the same interstitial related boron defect but with lower thermal stability in n-type Si.

A controlled clinical trial of Rifaprim (rifampicin 600 mg plus trimethoprim 160 mg, in a single daily dose at 10 p.m.) and cotrimoxazole (two tablets b.i.d.) was carried out in two groups of twenty out-patients, each with chronic or recurrent urinary tract infections. Both treatments lasted 10 days. At the first follow-up, 3–11 days after the end of treatment, bacteriological failure was observed in two Rifaprim patients and in four contrimoxazole patients. Clinical improvement with sterile urine or markedly reduced bacterial count was observed in nineteen Rifaprim patients and in fifteen cases of the other group. Mild allergic phenomena were observed in three Rifaprim patients, but they did not require discontinuation of treatment; anorexia was complained of by a cotrimoxazole patient. Rifaprim appears a valuable alternative in the treatment of chronic urinary tract infection, mainly because it reduces or abolishes the risk of emergence of resistance.

Summary Geochemical characteristics were systematically determined for Early Cretaceous samples of carbonatitic rocks from Eastern Paraguay (Rio Apa, Amambay and Central Provinces). The data show that all the occurrences have an enriched isotopic signature and that the carbonatites have negligible or absent crustal signature. A petrogenetic model (parent liquids, fractional crystallization, hydrothermal interactions and weathering) is proposed as a function of incompatible trace element, stable (O-C) and radiogenic (Sr-Nd) isotope variations with the aim to test the significance of carbonatitic complexes as a marker of the metasomatized subcontinental lithospheric mantle. The results indicate that the carbonatites and primary carbonates from eastern Paraguay, and those from the north eastern Paraná Basin (SE Brazil), were affected by metasomatic events distinct in time and composition.

Specimens of O. americanus collected in eight localities from Rio Grande do Sul and four from Paraná (Brasil) were studied. Patterns of chromosomal localization and activity of nucleolar organizer regions (NORs) were established using the silver banding technique. It was shown that diploid and tetraploid specimens from all localities have homologues of group 4 bearing active NORs. In addition, some populations showed NOR activity on only one homologue number 5 (Uruguaiana, Prudentópolis), 8 (Itaqui) or 2 (Pato Branco). Intrapopulation polymorphism was found, some specimens showing the extra band and others not. Most cells analysed from the intestinal epithelium of an individual showed the same particular staining pattern of NORs, which were unequally stained, suggesting differences in their activity. The tetraploid genomes showed a maximum of five and a minimum of two active NORs. Diploid genomes showed two active NORs and four in the case of one specimen from Pato Branco. Four diploid populations and sympatry of 2n and 4n animals in Santa Bárbara do Sul (RS) were detected for the first time in South Brasil. Karyological evolution, as well as the meaning of number and unequal activity of NORs on tetraploid genomes are discussed.

Malgré les progrès spectaculaires de la recherche, le cancer du sein reste un problème majeur de santé publique et une priorité de la recherche biomédicale. L’incidence du cancer du sein est plus élevée dans les pays occidentaux mais sa mortalité est relativement plus élevée dans les pays d’Afrique subsaharienne comme la République du Bénin (Afrique de l’Ouest). Plusieurs facteurs dont l’accès au diagnostic et aux soins opportuns pourraient expliquer ce constat. Mais, récemment, l’intérêt des chercheurs a été attiré par le cancer du sein survenant chez les jeunes femmes. En effet, chez les femmes âgées de moins de 45 ans, le cancer du sein la principale cause de décès par cancer. Le cancer du sein dans cette classe d’âge est par ailleurs corrélé à une survie inférieure et une fréquence plus élevée de caractéristiques clinicopathologiques péjoratives. Les études hospitalières réalisées en République du Bénin insistent sur le jeune âge des patientes mais aucune étude nationale n’a été réalisée. Par conséquent, les recommandations occidentales préconisant la mammographie de dépistage chez les femmes entre 50 et 74 ans sont encore largement utilisées. La détermination de l’âge du diagnostic des cancers du sein au Bénin aidera à l’adaptation de ces recommandations.

The authors describe an optical fiber link that is used in conjunction with the CERN host interface family to connect high-performance VAXes to VMEbus or FASTBUS over distances up to 1000 m. The modular construction allows other permutations, including VAX/VAX, FASTBUS/FASTBUS, VMEbus/VMEbus, or FASTBUS/VMEbus connections, over similar distances. The link comprises two identical optical data interconnects (ODI) connected by two unidirectional multimode fibers. The ODI at each end of the link can be connected to any device conforming to the DRB32 user interface specification. The authors discuss the operation of an ODI, the testing of the optical link, and present and future ODI implementations.<>

The direct ethanol fuel cell (DEFC) has received increasing attention once the complete ethanol oxidation is difficult to accomplish and, so far, no catalyst has efficiently cleaved the C-C bond. This paper reports on electrocatalysts supported on carbon containing 40 wt% metal loading of Pt, Ru, Ni, and Sn prepared by microwave-assisted heating. The electrocatalysts displayed homogeneously distributed particles ranging from 3 to 5 mm. The cyclic voltammetric and chronoamperometric curves recorded in the presence and absence of ethanol in acid medium exhibited the characteristic transition metal electrocatalyst profile. Acetic acid and acetaldehyde were the major products after 12 h of electrolysis. The best electrocatalyst in a single Direct Ethanol Fuel Cells (DEFC) was Pt75Sn13Ru11Ni1/C (55 mW cm−2). This value denoted that the catalyst performed surprisingly well at relatively low temperature (80°C).

We prepared different PtSnX (X = Ni, Ru, Rh, Pd, and W) nanocatalysts supported on Vulcan carbon XC-72 with 40 wt% metal loading by thermal decomposition of polymeric precursors (DPP) and tested their activity in the electrooxidation of ethanol in acidic medium (0.05 mol L−1H2SO4). We characterized the nanoparticles by EDX and XRD, which revealed 64% atomic ratio of Pt in an fcc structure with crystallite sizes of 4 to 10 nm. Electrochemical tests in the presence of ethanol showed that the addition of Ni to the PtSn/C nanocatalysts enhanced ethanol electrooxidation. The composition Pt66Sn11Ni23/C presented mass activity of 3.5 A gPt−1and power density of 25 mW cm−2in a direct ethanol fuel cell test. The Ni effect on the PtSn nanocatalyst prompted us to synthesize and test other compositions containing this metal and use them in a direct ethanol fuel cell station. The Pt82Sn09Ni09/C nanocatalyst delivered the best power density value (45 mW cm−2).