247 research outputs found
Sun-photometric measurements of atmospheric turbidity variations caused by the Pinatubo aerosol cloud in the Himalayan region during the summer periods of 1991 and 1992
Measurements of direct solar irradiance were taken episodically on two days of September 1990 and regularly in the summer periods from July to October 1991 and from
mid-July to mid-August 1992 at the Pyramid Laboratory (5050 m a.m.s.l.) situated at the foot of Mt. Everest (Nepal), using two examples of the Volz multispectral sunphotometer, model A. These sun-photometric measurements were analysed in terms of the Bouguer-Lambert-Beer law in order to
determine the values of aerosol optical thickness at the three sun-photometric window-wavelengths. Examining these spectral series in terms of the well-known Ångström formula, the best-fit values of turbidity parameters a and b were calculated with great accuracy. From the measurements taken in September 1990, we found values of the aerosol optical thickness in good agreement with the mean values of the background aerosol optical depth measured at the Mauna Loa Observatory (Hawaii) during the four-year period from 1988 to 1991. The spectral values of the aerosol optical thickness determined during the summer of 1991 show that the mean daily values of parameter b increased abruptly from about 0.06 to more than 0.16 from July 26 to 28, 1991, and then varied between 0.09 and 0.16 during the rest of the measurement period. Simultaneously, parameter a was found to decrease from more than 1.25 to 0.39 towards the end of July and to vary between 0.40 and 0.78 during September. These large variations of both atmospheric turbidity parameters have been attributed to the growth of the aerosol particles and to the consequent
changes in the size distribution curve of the Pinatubo aerosol particles. Analysing the variations of the stratospheric aerosol optical depth in terms of particle polydispersions consisting of a linear combination of a background aerosol monomodal model and a bimodal model representing the Pinatubo fresh aerosol particle size
distribution, the vertical mass loading of stratospheric aerosol particles was estimated to vary between 0.037 and 0.047 g m22 from July 24 to 27 and to increase to values ranging between 0.048 and 0.074 g m22 during the rest of summer 1991, presenting a mean value of (0.063 6 0.009) g m22 for the two-month period. The measurements taken in summer 1992 show that parameter b ranged between 0.08 and 0.12, while parameter a was found to vary between 0.23 and 0.73. The stratospheric aerosol depth values were analysed through a best-fit procedure based on a linear combination of a background model of small aerosol particles and a trimodal model consisting of aged volcanic aerosol particles. Following this procedure, the vertical mass loading of Pinatubo aerosol particles was found to vary between 0.043 and 0.057 g m22 during summer 1992, the mean value being evaluated as equal to (0.047 6 0.004) g m22
Esculetin provides neuroprotection against mutant huntingtin-induced toxicity in huntington’s disease models
Huntington’s disease (HD) is a neurodegenerative disorder caused by an abnormal CAG trinucleotide repeat expansion within exon 1 of the huntingtin (HTT) gene. This mutation leads to the production of mutant HTT (mHTT) protein which triggers neuronal death through several mechanisms. Here, we investigated the neuroprotective effects of esculetin (ESC), a bioactive phenolic compound, in an inducible PC12 model and a transgenic Drosophila melanogaster model of HD, both of which express mHTT fragments. ESC partially inhibited the progression of mHTT aggregation and reduced neuronal death through its ability to counteract the oxidative stress and mitochondria impairment elicited by mHTT in the PC12 model. The ability of ESC to counteract neuronal death was also confirmed in the transgenic Drosophila model. Although ESC did not modify the lifespan of the transgenic Drosophila, it still seemed to have a positive impact on the HD phenotype of this model. Based on our findings, ESC may be further studied as a potential neuroprotective agent in a rodent transgenic model of HD
From the dual function lead AP2238 to AP2469, a multi-target-directed ligand for the treatment of Alzheimer\u2019s disease
The development of drugs with different pharmacological properties appears to be an innovative therapeutic approach for Alzheimer\u2019s disease. In this article, we describe a simple structural modification of AP2238, a first dual function lead, in particular the introduction of the catechol moiety performed in order to search for multi-target ligands. The new compound AP2469 retains antiacetylcholinesterase (AChE) and beta-site amyloid precursor protein cleaving enzyme (BACE)1 activities compared to the reference, and is also able to inhibit Ab42 self aggregation, Ab42 oligomer-binding to cell membrane and subsequently reactive oxygen species formation in both neuronal and microglial cells. The ability of AP2469 to interfere with Ab42 oligomer-binding to neuron and microglial cell membrane gives this molecule both neuroprotective and antiinflammatory properties. These findings, together with its strong chain-breaking antioxidant performance, make AP2469 a potential drug able to modify the course of the diseas
Chemical characterization of the stained glass window from the rose window, Siena Duomo (Italy, 1288-1289)
[EN] The chemical composition of nine medieval coloured stained glasses from Duomo (Catedral) of Siena, Italy, has been
characterized. They come from the rose window elaborated under the drawing of Duccio di Buoninsegna masterwork (1288-
89 AD). This note explains the results obtained by EMPA, representative of bulk chemistry of several coloured glasses (deep
green, olive green, yellow, purple, pink, deep blue, light blue, red plaqué and also uncoloured), as well as the associated
trace elements (obtained by Induced Coupled Plasma Mass Spectrometry) that represent the chemical fingerprint of these
glasses. The studied samples are sodium-calcium glass (chemical compositions in the range 13-14 wt% Na2O, 56-64 wt%
SiO2, 4 wt% MgO, 9-10 wt% CaO, 2,5-4 wt% K2O); thus of Mediterranean tradition.This fact has been found by our team in
previous studies (stained glasses from the church of Monestir de Pedralbes, Barcelona) for XIV century glass made at least
40 years later. As a general rule, the conservation state of these sodium glasses is good, except for the cohesion of grisaille
to glass mesostase.
This study allowed to identify three glass groups developed from different raw material formulations: a first group is
constituted by deep green, olive green, light blue and yellow glass; a second one comprises by uncoloured, deep purple,
deep blue and pink glass; and finally, the plaqué red glass that shows deeply different composition. Pink and yellow glass
was produced following the traditional recipe compiled by Theophilus, a monk who lived at the beginning of XII century.
This implies a separate process of raw material purification and a careful control of the redox kiln conditions; thus, these
glasses can be considered as traditional or technologically not evolved. The deep blue, light blue and deep purple were
obtained after the artisan dosed addition of a cobalt salt. Olive green and deep green glasses were produced with addition
of copper (together with manganese and iron), previously prepared as a pigment that has as excipient a potassium glass.
The use of potassium glass instead of the sodium glass locally produced strongly suggests that the pigment could be bought
directly from Middle or Northern Europe markets and/or could be a sub-product of copper ore melting. On the other hand,
the production of sodium red ruby plaqué glass, technologically more evolved and comparable to the coeval potassium glass
coming from the Central Europe glass factories, would be outstanding in the XIV century; but we interpret (taking into
account its chemical composition) that was produced later and introduced during the restoration conducted at the end of
XVII century. We can also note the use of well-dosed lead additions in order to increase the lightness and transparency of
coloured glass. Manganese has been a very important element in the Siena workshop glassmaker colour palette achievements.
On the other hand, the trace-element chemical fingerprint of the glass allows arguing what kind of mineral salts were used
as pigments, as well as the way to introduce it in the uncoloured original glass.[ES] Se han caracterizado químicamente una colección de vidrios arquitectónicos coloreados originales del rosetón del Duomo
(catedral) de Siena, Italia, realizados bajo diseño del artista Duccio di Buoninsegna en 1288-89. Esta comunicación expone los
resultados obtenidos mediante el empleo de microsonda electrónica de Castaing (mayoritarios) y espectrometría de masas
con fuente de plasma acoplado inductivamente (ICP-MS, elementos en traza) en vidrios de varios colores (incoloro, verde
oscuro, verde oliva, amarillo, violeta, rosa, azul oscuro, azul celeste, rojo plaqué). Se trata de vidrios sódico-cálcicos (valores
en peso alrededor del 13-14 % de Na2O, 56-64 % SiO2, 4% MgO, 9-10 % CaO, 2,5-4 K2O) de tradición por tanto mediterránea.
Un resultado semejante se encontró precedentemente para vidrios realizados a lo largo del siglo XIV, cuanto menos unos 40
años después (vidriera de la iglesia del Monestir de Pedralbes, Barcelona). En general, el estado de conservación de estos
vidrios es bueno, excepto por lo que se refiere a la adherencia de las grisallas al vidrio base.
El estudio desarrollado ha permitido identificar tres grupos de vidrios desarrollados a partir de formulaciones de diferentes
composiciones: un primer grupo constituido por los vidrios de color verde claro, verde oscuro, azul celeste y amarillo; un
segundo grupo constituido por los vidrios incoloro, violeta, azul oscuro, y malva; y finalmente el vidrio rojo plaqué, de
composición netamente diferente a todos los demás. Desde el punto de vista de la obtención de los colores, cabe destacar que
los datos químicos permiten deducir que el malva y el amarillo han sido elaborados siguiendo la receta tradicional del monje
Theophilus de inicios del siglo XII, utilizando un proceso de purificación especial de las materias primas, y controlando
artesanalmente las condiciones redox del horno; en este sentido, estos vidrios se pueden calificar como tradicionales o
tecnológicamente poco evolucionados. Los colores azul oscuro, violeta y azul celeste se han obtenido mediante la adición de
una misma sal de cobalto en diferentes dosis, y los colores verde oliva y verde oscuro mediante la adición de cobre (junto
con manganeso y hierro), previamente preparados en un colorante que tiene como excipiente un vidrio potásico. Este último
hecho (el empleo de vidrio potásico no usual en los centros productores del área mediterránea) permite suponer que el color
puede haber sido comprado directamente a un fabricante centroeuropeo o que se tratara de un subproducto de fundición
de minerales de cobre. Por su parte, la fabricación del vidrio plaqué, tecnológicamente más complejo y comparable al vidrio
rojo plaqué potásico centroeuropeo contemporáneo indicaría, si fuera original, la incorporación de este proceso tecnológico
al taller local. En opinión de los autores se trata de un vidrio de producción local mucho más tardia, incorporado en la
restauración documentada a finales del siglo XVII. Destaca también, como en Pedralbes, el empleo del plomo para aumentar
la luminosidad y transparencia del vidrio, en dosis variables atendiendo al color del vidrio. Por otro lado hay que señalar que
en Siena el manganeso es un elemento muy importante con el que el fabricante del vidrio jugó intensamente para obtener
la paleta de colores. El análisis de los metales presentes como elementos traza, y de las tierras raras, permite establecer
sólidas hipótesis sobre el tipo de sales minerales empleadas como colorantes y como fueron incorporados al vidrio incoloro
original.Este trabajo se ha podido realizar
en el marco de diferentes proyectos financiados (proyecto
3338 de la Fundació Bosch i Gimpera, UB; acción integrada
hispano-italiana HI2006-0190: La producción y el comercio
del vidrio plano en Europa y en el Mediterráneo Occidental,
entre los siglos XI y XV: un estudio arqueométrico) . La
caracterización geoquímica de los vidrios mediante MSE e
ICP-MS se ha llevado a cabo en los Serveis Científico-Tècnics
de la Universitat de Barcelona (SCT-UB);Peer reviewe
Miconazole as adjuvant therapy for oral lichen planus : a double-blind randomized controlled trial
Background: Topical steroids are the first choice for the treatment of oral lichen planus (OLP). Antifungal drugs are often employed together with them, to prevent secondary oral candidosis, although it has been suggested anecdotally that they can also be beneficial for OLP itself. Objectives: To compare the effect of clobetasol propionate with and without a topical antifungal drug (miconazole) on the symptoms and extension of OLP. Methods: A randomized, parallel, double-blind trial was conducted at the Unit of Oral Medicine and Pathology of the University of Milan. Thirty-five outpatients with histologically proven OLP were randomly assigned to receive either clobetasol propionate and miconazole, or clobetasol propionate and placebo for 6 weeks. Primary outcomes included symptoms and extension of lesions; adverse effects were also recorded. Results: All the patients who concluded the study (30 of 35) showed clinical and subjective improvement within 3 weeks. The addition of miconazole did not affect in a significant way the signs and symptoms of OLP. No cases of clinical candidosis were seen in the patients taking miconazole, while one-third (five of 15) of the placebo group were affected. Conclusions: Although effective in preventing iatrogenic candidosis, the addition of miconazole to topical steroid treatment does not improve the efficacy of the therapy
Dementia-related genetic variants in an Italian population of early-onset Alzheimer’s disease
Early-onset Alzheimer’s disease (EOAD) is the most common form of early-onset dementia. Although three major genes have been identified as causative, the genetic contribution to the disease remains unsolved in many patients. Recent studies have identified pathogenic variants in genes representing a risk factor for developing Alzheimer’s disease (AD) and in causative genes for other degenerative dementias as responsible for EOAD. To study them further, we investigated a panel of candidate genes in 102 Italian EOAD patients, 45.10% of whom had a positive family history and 21.74% with a strong family history of dementia. We found that 10.78% of patients carried pathogenic or likely pathogenic variants, including a novel variant, in PSEN1, PSEN2, or APP, and 7.84% showed homozygosity for the ε4 APOE allele. Additionally, 7.84% of patients had a moderate risk allele in PSEN1, PSEN2, or TREM2 genes. Besides, we observed that 12.75% of our patients carried only a variant in genes associated with other neurodegenerative diseases. The combination of these variants contributes to explain 46% of cases with a definite familiarity and 32% of sporadic forms. Our results confirm the importance of extensive genetic screening in EOAD for clinical purposes, to select patients for future treatments and to contribute to the definition of overlapping pathogenic mechanisms between AD and other forms of dementia
Efficacy of hyaluronic acid binding assay in selecting motile spermatozoa with normal morphology at high magnification
<p>Abstract</p> <p>Background</p> <p>The present study aimed to evaluate the efficacy of the hyaluronic acid (HA) binding assay in the selection of motile spermatozoa with normal morphology at high magnification (8400x).</p> <p>Methods</p> <p>A total of 16592 prepared spermatozoa were selected and classified into two groups: Group I, spermatozoa which presented their head attached to an HA substance (HA-bound sperm), and Group II, those spermatozoa that did not attach to the HA substance (HA-unbound sperm). HA-bound and HA-unbound spermatozoa were evaluated according to the following sperm forms: 1-Normal morphology: normal nucleus (smooth, symmetric and oval configuration, length: 4.75+/-2.8 μm and width: 3.28+/-0.20 μm, no extrusion or invagination and no vacuoles occupied more than 4% of the nuclear area) as well as acrosome, post-acrosomal lamina, neck, tail, besides not presenting a cytoplasmic droplet or cytoplasm around the head; 2-Abnormalities of nuclear form (a-Large/small; b-Wide/narrow; c-Regional disorder); 3-Abnormalities of nuclear chromatin content (a-Vacuoles: occupy >4% to 50% of the nuclear area and b-Large vacuoles: occupy >50% of the nuclear area) using a high magnification (8400x) microscopy system.</p> <p>Results</p> <p>No significant differences were obtained with respect to sperm morphological forms and the groups HA-bound and HA-unbound. 1-Normal morphology: HA-bound 2.7% and HA-unbound 2.5% (P = 0.56). 2-Abnormalities of nuclear form: a-Large/small: HA-bound 1.6% vs. HA-unbound 1.6% (P = 0.63); b-Wide/narrow: HA-bound 3.1% vs. HA-unbound 2.7% (P = 0.13); c-Regional disorders: HA-bound 4.7% vs. HA-unbound 4.4% (P = 0.34). 3. Abnormalities of nuclear chromatin content: a-Vacuoles >4% to 50%: HA-bound 72.2% vs. HA-unbound 72.5% (P = 0.74); b-Large vacuoles: HA-bound 15.7% vs. HA-unbound 16.3% (P = 0.36).</p> <p>Conclusions</p> <p>The findings suggest that HA binding assay has limited efficacy in selecting motile spermatozoa with normal morphology at high magnification.</p
Recurrent Scedosporium apiospermum mycetoma successfully treated by surgical excision and terbinafine treatment: a case report and review of the literature
Background:
Scedosporium apiospermum
is an emerging opportunistic filamentous fungus, which is notorious for its
high levels of antifungal
‑resistance. It is able to cause localized cutaneous or subcutaneous infections in both immu‑
nocompromised and immunocompetent persons, pulmonary infections in patients with predisposing pulmonary
diseases and invasive mycoses in immunocompromised patients. Subcutaneous infections caused by this fungus
frequently show chronic mycetomatous manifestation.
Case report:
We report the case of a 70
‑year
‑old immunocompromised man, who developed a fungal mycetoma‑
tous infection on his right leg. There was no history of trauma; the aetiological agent was identified by microscopic
examination and ITS sequencing. This is the second reported case of
S. apiospermum
subcutaneous infections in
Hungary, which was successfully treated by surgical excision and terbinafine treatment. After 7
months, the patient
remained asymptomatic. Considering the antifungal susceptibility and increasing incidence of the fungus,
Sce
-
dosporium
related subcutaneous infections reported in the past quarter of century in European countries were also
reviewed.
Conclusions:
Corticosteroid treatment represents a serious risk factor of
S. apiospermum
infections, especially if the
patient get in touch with manure
‑enriched or polluted soil or water. Such infections have emerged several times in
European countries in the past decades. The presented data suggest that besides the commonly applied voricona‑
zole, terbinafine may be an alternative for the therapy of mycetomatous
Scedosporium
infections
The census as an information source in public policy-making
This paper provides an assessment of the value of national population censuses as information sources with specific reference toUK census data and its use in policy-making. Mixed methods were adopted to collect quantitative and qualitative data from twosources: (1) a content analysis of policy documents, and (2) interviews with policy-makers in Scotland. The findings highlight thatalthough the general value of the census is recognised, policy-makers are not necessarily closely engaged with the census as a toolfor directing the development and implementation of policy. This is evident, for example in a lack of awareness of proposed changesto the census, and infrequent deployment of available data. The opportunity to change perceptions among policy-makers, and toexpand the application of census data in public policy, is identified. With a novel focus on the deployment of censuses as sources ofevidence for policy-making that includes the views of policy-makers from both within and beyond government, this workcontributes to an established body of global research on international censuses
EUCAARI ion spectrometer measurements at 12 European sites – analysis of new particle formation events
We present comprehensive results on continuous atmospheric cluster and particle measurements in the size range ~1–42 nm within the European Integrated project on Aerosol Cloud Climate and Air Quality interactions (EUCAARI) project. We focused on characterizing the spatial and temporal variation of new particle formation events and relevant particle formation parameters across Europe. Different types of air ion and cluster mobility spectrometers were deployed at 12 field sites across Europe from March 2008 to May 2009. The measurements were conducted in a wide variety of environments, including coastal and continental locations as well as sites at different altitudes (both in the boundary layer and the free troposphere). New particle formation events were detected at all of the 12 field sites during the year-long measurement period. From the data, nucleation and growth rates of newly formed particles were determined for each environment. In a case of parallel ion and neutral cluster measurements, we could also estimate the relative contribution of ion-induced and neutral nucleation to the total particle formation. The formation rates of charged particles at 2 nm accounted for 1–30% of the corresponding total particle formation rates. As a significant new result, we found out that the total particle formation rate varied much more between the different sites than the formation rate of charged particles. This work presents, so far, the most comprehensive effort to experimentally characterize nucleation and growth of atmospheric molecular clusters and nanoparticles at ground-based observation sites on a continental scale
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