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1.
J Helminthol ; 96: e9, 2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35115061

RESUMO

Gyrodactylus sphinx Dmitrieva & Gerasev, 2000 is the only species of Gyrodactylus originally described from Aidablennius sphynx (Valenciennes) in the Black Sea. In the present study, monogeneans similar to G. sphinx are reported from the same host and from two other species of Blenniidae from the Black Sea, as well as from the Mediterranean Sea. This study aims to verify the taxonomic status of the specimens found in different hosts and localities, other than the type ones of G. sphinx. Twenty-two measurements of the haptoral structures of 169 gyrodactylids were used for the morphological study. Morphometric variability between different samples was analysed using analysis of variance, multivariate analysis of variance (MANOVA) and principal component analysis (PCA). Molecular studies were carried out using the nuclear internal transcribed spacer 2 and 5.8S ribosomal DNA regions. Network, Bayesian phylogenetic and species delimitation analyses were performed to infer the number of taxonomic units and the phylogeographic relationships occurring within and among them. MANOVA revealed a significant dependence of the morphometry of hamuli and marginal hooks on host species and regions, but a clear differentiation between samples was not confirmed by PCA. Moreover, the ranges of all dimensions overlapped between samples. However, molecular analyses suggested the occurrence of at least two taxonomic entities. The most common entity was present in individuals of the Black and Mediterranean seas, and is described here as Gyrodactylus gerasevi n. sp., whereas a second entity recognized as a G. sphinx was found only in individuals from two localities off Crimea. The monophyletic cluster grouping of these two species was placed within a large clade that also included a separate sister cluster with seven other species of the Gyrodactylus orecchiae cross-ocean species group.


Assuntos
Doenças dos Peixes , Trematódeos , Animais , Teorema de Bayes , Mar Negro , Humanos , Mar Mediterrâneo , Filogenia , Especificidade da Espécie , Trematódeos/genética
2.
Helminthologia ; 59(2): 152-164, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36118371

RESUMO

This study aims to investigate the level of genetic variability of Fasciola hepatica flukes isolated from cattle in Algeria and to determine the phylogenetic and phylogeographic relationships with sequences isolated worldwide. Mitochondrial (Cytochrome c Oxidase subunit I gene - COI) and nuclear markers (Internal Transcribed Spacers of nuclear ribosomal DNA - ITS) for 24 F. hepatica flukes isolated from 12 cattle in North Algeria were characterised. Only two haplotypes were obtained for the COI gene, resulting in a low level of genetic variation. The analysis of variation among the COI sequences isolated from around the world did not show high levels of genetic divergence, and the phylogenetic analysis revealed a genetic similarity among F. hepatica isolates from different areas of the world. The analysis of the ITS region showed a low level of variability, which prevented obtaining informative phylogenetic and phylogeographic results. The present study also revealed that specimens of F. hepatica are genetically similar in different hosts, indicating that the genetic structure among populations of this parasite is not influenced by the host species. The low levels of genetic variation for COI and ITS regions among fluke isolates from all continents are consistent with a common origin for the flukes' worldwide distribution.

3.
Parasitol Res ; 119(1): 63-73, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31813012

RESUMO

This study provides updated information on the distribution of the phlebotomine sand fly species and their genetic characterization in Sardinia, a Mediterranean island where leishmaniasis is endemic. From April to November 2017, sand flies were trapped in five different capture sites using sticky traps and light traps as collection methods, operated nearby sheep, poultry, cat, and dog shelters. Phlebotomine specimens (n = 513) collected were morphologically and molecularly identified as Phlebotomus perniciosus (249/513, 48.5%), Phlebotomus perfiliewi (236/513; 46%), and Sergentomyia minuta (28/513, 5.5%). Sand flies were collected from the second half of May to October confirming the well-defined seasonal activity, which peaks in August in Sardinia. Overall, correlation analyses indicated a significant positive association between the monthly number of sand flies collected and the mean temperature (r = 0.88, rho = 0.87, and tau = 0.69, P < 0.05), while there was non-significant, moderately negative correlation between the monthly number of sand flies collected and the monthly mean relative humidity and wind (r = - 0.22, rho = 0.02, and tau = 0.04, P > 0.05). This study provides the first data on the molecular characterization of phlebotomine sand flies in this region and confirms the presence of three sand fly species. Molecular results suggest that the morphological features used for analysis represent synapomorphic-derived characters which are shared among descendant taxa and the common ancestor.


Assuntos
Phlebotomus/classificação , Phlebotomus/genética , Animais , Gatos , Cães , Feminino , Insetos Vetores , Itália/epidemiologia , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/parasitologia , Phlebotomus/parasitologia , Ovinos , Temperatura
4.
Acc Chem Res ; 51(3): 753-760, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29465979

RESUMO

In the last decade technology has brought significant changes to our lives, including new habits and a new view on social relationships. These technological innovations are based on several factors, one of which is miniaturization. This was made possible also due to the discovery and synthesis of new materials with characteristics at the nanoscale that are designed for specific purposes. This "on purpose" approach, joined to the development of preparation and growth methods, has led to use of thin films rather than bulk materials in devices. Using thin films makes devices easier to produce, and using films for coating protects the devices and gives specific properties to surfaces. For several decades thin films, surfaces, and interfaces have been intensively investigated. Indeed, device performances rely on the optimized match of thin films of different natures, such as organic and inorganic semiconductors and metals for contacts. Surprisingly, in comparison, little attention has been devoted to the deposition of organic radicals on a substrate. This might be because these materials are considered not stable enough for evaporation. In this work, we demonstrate that it is possible to evaporate and deposit organic radicals onto well-defined surfaces under controlled conditions, without degradation. Using soft X-ray spectroscopies, performed also at synchrotrons, we investigate thin film processes, surfaces, and interfaces at the nanoscale, when organic radicals are deposited on metal and metal oxide surfaces. We suggest how to design organic radicals bearing in mind the thermodynamic factors that govern thin film stability, with the purpose of obtaining not only a chemically stable radical, but also stable thin films. We investigate the thermal and air stability of the deposited films, and we explore the influence of the surface/radical chemical bond and the role of surface defects on the magnetic moment at the interface. We find that organic radicals are physisorbed and keep their magnetic moment on inert and passivated surfaces such as Au(111) and Al2O3(112̅0) single crystals, SiO2, and ideal TiO2(110) single crystals, while defective sites such as oxygen vacancies or the presence of OH groups lead to chemisorption of the organic radicals on the surface with quenching of their magnetic moment. Our work shows that the use of X-ray based techniques represents a powerful approach to reveal the mechanisms governing complex interfaces, such as radical/metal and radical/metal-oxide, where it is important to describe both charge and spin behavior (spinterfaces). It also makes it possible to conceive new experiments to investigate the magnetic character of the thin films versus their structural properties, toward tuning the arrangement of the molecules in films. Controlling the molecular arrangement will give the opportunity to tune the mutual position and orientation of the molecules, that is, of the single magnetic moments in the films, "imprinting" their magnetic properties. A deep understanding of stable radical/inorganic spinterfaces may open the way to use radicals in solid state devices or as quantum bits with dedicated configurations, as proposed for other molecular quantum bits, and in spin-based electronics.

5.
Phys Chem Chem Phys ; 18(19): 13693-700, 2016 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-27140434

RESUMO

We have investigated diindenoperylene (DIP) thin films deposited on Au(110) single crystals, by using a multi-technique approach based on X-ray photoemission spectroscopy (XPS), resonant photoemission spectroscopy (RPES), near edge X-ray absorption fine structure (NEXAFS) spectroscopy, atomic force microscopy (AFM) and photoemission electron microscopy (PEEM). DIP molecules are physisorbed on gold, with image-charge screening playing the major role as an interface phenomenon. DIP thin films show Stranski-Krastanov growth mode and the structural herringbone arrangement mimics the arrangement found in DIP single crystals. These results are common with the (100) and (111) gold substrate geometries. On the contrary, the island aggregation is substrate geometry-dependent. This paves the way to exploit the degree of anisotropy in different lattice geometries as a tool for molecular patterning of inorganic surfaces, keeping the electronic structure preserved.

6.
J Fish Biol ; 82(3): 856-76, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23464548

RESUMO

This study provides data on the genetic structuring of the pipefish Syngnathus abaster in the western Mediterranean and Adriatic Seas. A total of 109 specimens were collected in brackish-water biotopes. The control region and three other regions of the mitochondrial genome were analysed. The most relevant result was the high genetic structuring found by Bayesian inference (BI), maximum likelihood (ML) and network analyses, which were consistent in showing three well-separated clusters of S. abaster populations. Furthermore, BI and ML did not support the monophyly of the taxon S. abaster. These results suggest the occurrence of a species complex in the study area, whose differentiation may have occurred since the Pleistocene. The results also show a very high genetic variability at the inter-population level, with no shared haplotypes among sites. Evolutionary forces due to the fragmented nature of the brackish-water habitats may account for the high genetic divergence found among the groups and populations. Finally, although dispersal by rafting over long distances may occasionally occur, this study suggests linear stepping-stone model of colonization to be most likely. The complexity of the results obtained suggests that further studies are needed to elucidate the phylogeny of S. abaster.


Assuntos
DNA Mitocondrial/genética , Evolução Molecular , Variação Genética , Filogenia , Smegmamorpha/genética , Animais , Teorema de Bayes , Haplótipos , Funções Verossimilhança , Mar Mediterrâneo , Análise de Sequência de DNA
7.
ACS Appl Mater Interfaces ; 15(25): 30935-30943, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37319383

RESUMO

Blatter radical derivatives are very attractive due to their potential applications, ranging from batteries to quantum technologies. In this work, we focus on the latest insights regarding the fundamental mechanisms of radical thin film (long-term) degradation, by comparing two Blatter radical derivatives. We find that the interaction with different contaminants (such as atomic H, Ar, N, and O and molecular H2, N2, O2, H2O, and NH2) affects the chemical and magnetic properties of the thin films upon air exposure. Also, the radical-specific site, where the contaminant interaction takes place, plays a role. Atomic H and NH2 are detrimental to the magnetic properties of Blatter radicals, while the presence of molecular water influences more specifically the magnetic properties of the diradical thin films, and it is believed to be the major cause of the shorter diradical thin film lifetime in air.

8.
J Chem Phys ; 134(1): 014504, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21219004

RESUMO

Resonant and preresonant Raman spectra obtained on diindenoperylene (DIP) thin films are interpreted with calculations of the deformation of a relaxed excited molecule with density functional theory (DFT). The comparison of excited state geometries based on time-dependent DFT or on a constrained DFT scheme with observed absorption spectra of dissolved DIP reveals that the deformation pattern deduced from constrained DFT is more reliable. Most observed Raman peaks can be assigned to calculated A(g)-symmetric breathing modes of DIP or their combinations. As the position of one of the laser lines used falls into a highly structured absorption band, we have carefully analyzed the Raman excitation profile arising from the frequency dependence of the dielectric tensor. This procedure gives Raman cross sections in good agreement with the observed relative intensities, both in the fully resonant and in the preresonant case.


Assuntos
Indenos/química , Membranas Artificiais , Perileno/análogos & derivados , Perileno/química , Teoria Quântica , Análise Espectral Raman
9.
Nutr Metab Cardiovasc Dis ; 20(9): 633-40, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20399085

RESUMO

BACKGROUND AND AIMS: Vitamin D deficiency has been associated with chronic heart failure (CHF). We evaluated vitamin D levels in relationship with New York Heart Association (NYHA) classes, N-terminal pro-brain natriuretic peptide (NT-proBNP) values and left ventricular (LV) measures in ≥60 year old patients with stable CHF. Differently from previous investigations, LV function was assessed by transthoracic echocardiography, to provide easily reproducible results. METHODS AND RESULTS: The study was performed at geographic latitude 44° N, from March to May and from September to November 2008. Acute HF and diseases or drugs altering vitamin D status were exclusion criteria. NYHA scores and 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D and NT-proBNP concentrations were assessed in 90 (45 F, 45 M) Caucasian patients with CHF secondary to hypertension and/or coronary artery disease. Vitamin D levels were also measured in 31 subjects without heart disease (controls). LV echocardiography was performed in 52 (26 F, 26 M) representative patients. Vitamin D concentrations were significantly lower in CHF cases than in controls. Among subject with CHF, 97.8% presented vitamin D deficiency (25(OH)D<75 nmol/L), being severe (<25 nmol/L) in 66.7%. LV end-diastolic and end-systolic diameters were significantly longer, LV end-diastolic and end-systolic volumes bigger and fractional shortening lower in CHF patients with 25(OH)D<25 nmol/L than with 25(OH)D≥25 nmol/L (p<0.05). Log-values of 25(OH)D were negatively correlated with LV end-systolic diameter and volume (r=-0.28; p<0.05). On subgroup analysis, these results persisted only in male patients. CONCLUSIONS: In elderly CHF patients, vitamin D deficiency was highly prevalent and often severe. This first addressed echocardiography study showed a sex-specific association between vitamin D deficiency and LV dilation. Since further echocardiography data are easily obtainable, larger investigations are demanded.


Assuntos
Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Ecocardiografia , Feminino , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/sangue
10.
Science ; 200(4341): 552-4, 1978 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-205949

RESUMO

The intraventricular injection of methionine-enkephalin (50 to 100 micrograms) or [d-Ala2]-methionine-enkephalinamide (1.5 to 12 micrograms), a synthetic enkephalin analog resistant to enzyme degradation, caused a marked dose-dependent increase in dihydroxyphenylacetic acid and homovanillic acid concentrations in the rat striatum. The [d-Ala2] analog increased the accumulation of dopa in the striatum after aromatic amino acid decarboxylase inhibition, indicating that it increased dopamine synthesis. At the highest doses used both enkephalins failed to modify brain serotonin metabolism. The monolateral microinjection of the [d-Ala2]] analog (3 to 6 micrograms) into the caudate nucleus increased the concentration of dihydroxyphenylacetic acid in the injected side, whereas bilateral injection increased the concentration of this compound in both caudate nuclei and caused catalepsy. The stimulant effect of the [d-Ala2] analog on dopamine synthesis in the striatum persisted after destruction of striatal postsynaptic dopamine receptors with kainic acid. The biochemical and behavioral effects of enkephalins were prevented by naloxone, a specific narcotic antagonist. The results indicate that enkephalins stimulate dopamine synthesis by an action on opioid receptors localized on dopaminergic nerve terminals.


Assuntos
Núcleo Caudado/metabolismo , Dopamina/biossíntese , Endorfinas/farmacologia , Encefalinas/farmacologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Encefalinas/antagonistas & inibidores , Ácido Homovanílico/metabolismo , Ácido Caínico/farmacologia , Masculino , Naloxona/farmacologia , Ratos , Receptores Dopaminérgicos/efeitos dos fármacos , Receptores Opioides/efeitos dos fármacos
11.
Phys Chem Chem Phys ; 11(40): 9000-4, 2009 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-19812817

RESUMO

The results of our multitechnique investigation performed on diindenoperylene thin films deposited on rutile TiO2(110) show island growth, with crystallites nucleating preferentially along the [110] substrate crystallographic axis. The findings evidence that the films' properties at the interface are common to those found for a number of organic molecules deposited on the same substrate, revealing that the structural and morphological properties of organic thin films on rutile TiO2(110) are completely driven by its surface morphology.

12.
J Chem Phys ; 130(19): 194705, 2009 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-19466853

RESUMO

We study the electronic structure of zinc phthalocyanine (ZnPc) and 1,4-octa-decyl substituted zinc phthalocyanine [(Dec)(8)PcZn] thin films (approximately 6-15 nm) using resonant photoemission spectroscopy and X-ray absorption spectroscopy (XAS) at room temperature and at liquid He temperature. From XAS we conclude that the probability amplitude of the lowest unoccupied molecular orbital is located predominantly at the inner C and N atoms of the molecules. Nonlinear energy shifts in resonant photoemission were observed; large shifts are explained by reduced electrical conductivity of inhomogeneously oriented molecules.

13.
J Phys Condens Matter ; 21(31): 314017, 2009 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21828578

RESUMO

We present the results of photoemission electron microscopy investigations on diindenoperylene (DIP) thin films deposited on polycrystalline gold, prepared in order to have a roughness much larger than the molecular size. Our investigations revealed the ability of the DIP molecule to form well-organized films, exhibiting a different molecular orientation with respect to the already known λ and σ phases. In locally thicker film regions, the energy of the films is minimized by a molecular arrangement that has an asymptotic tendency to the σ phase.

14.
J Chem Phys ; 129(24): 244708, 2008 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-19123527

RESUMO

Thin films of perylene on Si(111) and Si(100) substrates have been investigated using a variety of experimental techniques. We find that the structural and morphological properties as well as the growth modes strongly depend on the preparation parameters. In general, we observe the existence of a relatively weak coupling between perylene and the two single crystal substrates. However, under special preparation conditions, it is possible to obtain a multilayer phase on the Si(111) substrate that is characterized by flat-lying, parallel-oriented molecules, and strong coupling with the substrate in the first layer. This phase has different structural, electronic, and intermolecular bonding properties as compared to the known crystalline phases. On Si(100), by varying the deposition rate between 0.1 and 10 nm/min, it is possible to observe a transition from island growth mode, with large and isolated crystallites, to homogeneous film growth. These findings contribute to the basic knowledge for film engineering. Thus, the film morphology could be designed ranging from the growth of very large single grains suitable for a complete nanodevice to homogenous films for application in large displays.

15.
J Endocrinol Invest ; 31(11): 1014-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19169059

RESUMO

CONTEXT: Autonomic nervous system imbalance is related to cardiovascular risk. Heart rate variability (HRV) indexes are associated with age, race, and sex, but the role of sex hormones is still unknown. OBJECTIVE: To evaluate sympathovagal balance (SB) in transsexuals. PATIENTS: Eighteen transsexual subjects, 12 male-to-female (group 1) and 6 female- to-male (group 2), compared with 34 age-matched controls: 17 males (group 3) and 17 females (group 4). Autonomic testing of SB was performed by Power Spectral Analysis (PSA) of HRV in clinostatism (c) and orthostatism (o). PSA identifies power peaks: high frequency (HF) expresses vagal activity, while low frequency (LF) expresses sympathetic activity. RESULTS: Group 1 showed lower LFc than groups 2, 3, and 4 (p<0.001, p=0.05, p<0.001, respectively), and lower LFo than groups 3 and 4 (p=0.01); HFc was lower than in groups 2, 3, and 4 (p=0.02, p=0.02, p<0.001, respectively), and HFo was lower than in groups 3 and 4 (p<0.001). LFo/HFo ratio was higher in group 1 than in group 4 (p<0.001). No differences emerged between groups 2 and 3. Group 2 showed lower HFo than group 4 (p=0.03), and a higher LFo/HFo ratio (p=0.01). Group 3 showed lower HFo and HFc than group 4 (p=0.02, p=0.05, respectively), and a higher LFo/HFo ratio (p=0.03). CONCLUSION: In this study we found a sympathovagal imbalance due to a reduced sympathetic and parasympathetic influence on heart rate. Sex hormone therapy per se may play a role in this imbalance, and HRV measurement could be useful in detecting cardiovascular risk in transsexuals.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Frequência Cardíaca , Transexualidade/fisiopatologia , Nervo Vago/fisiopatologia , Adulto , Doenças Cardiovasculares/etiologia , Feminino , Humanos , Masculino , Fatores de Risco
16.
Comput Methods Programs Biomed ; 90(2): 124-36, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18262677

RESUMO

The vast amount of heterogeneous data generated in various fields of neurosciences such as neuropsychopharmacology can hardly be classified using traditional databases. We present here the concept of a virtual archive, spatially referenced over a simplified 3D brain map and accessible over the Internet. A simple prototype (available at http://aquatics.crs4.it/neuropsydat3d) has been realized using current Web-based virtual reality standards and technologies. It illustrates how primary literature or summary information can easily be retrieved through hyperlinks mapped onto a 3D schema while navigating through neuroanatomy. Furthermore, 3D navigation and visualization techniques are used to enhance the representation of brain's neurotransmitters, pathways and the involvement of specific brain areas in any particular physiological or behavioral functions. The system proposed shows how the use of a schematic spatial organization of data, widely exploited in other fields (e.g. Geographical Information Systems) can be extremely useful to develop efficient tools for research and teaching in neurosciences.


Assuntos
Encéfalo/anatomia & histologia , Gráficos por Computador , Neurofarmacologia , Psicofarmacologia , Interface Usuário-Computador , Animais , Biologia Computacional , Humanos , Internet , Modelos Anatômicos , Modelos Neurológicos
17.
J Endocrinol Invest ; 30(5): 356-62, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17598965

RESUMO

Changes in body composition, hormone secretions, and heart function with increased risk of sudden death occur in eating disorders. In this observational clinical study, we evaluated sympathovagal modulation of heart rate variability (HRV) and cardiovascular changes in response to lying-to-standing in patients with anorexia (AN) or bulimia nervosa (BN) to analyze: a) differences in autonomic activity between AN, BN, and healthy subjects; b) relationships between autonomic and cardiovascular parameters, clinical data and leptin levels in patients with eating disorders. HRV, assessed by power spectral analysis of R-R intervals, blood pressure (BP) and heart rate (HR) were studied by tilt-table test in 34 patients with AN, 16 with BN and 30 healthy controls. Autonomic and cardiovascular findings were correlated with clinical data, and serum leptin levels. Leptin levels were lowered in AN vs BN and healthy subjects (p<0.0001), but both AN and BN patients showed unbalanced sympathovagal control of HRV due to relative sympathetic failure, prevalent vagal activity, impaired sympathetic activation after tilting, independently from their actual body weight and leptin levels. No significant correlations were obtained between HRV data vs clinical data, BP and HR findings, and leptin levels in eating disorders. Body mass indices (BMI) (p<0.02), and leptin levels (p<0.04) correlated directly with BP values. Our data showed alterations of sympathovagal control of HRV in eating disorders. These changes were unrelated to body weight and BMI, diagnosis of AN or BN, and leptin levels despite the reported effects of leptin on the sympathetic activity.


Assuntos
Anorexia Nervosa/fisiopatologia , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Bulimia Nervosa/fisiopatologia , Frequência Cardíaca/fisiologia , Leptina/sangue , Nervo Vago/fisiologia , Adulto , Anorexia Nervosa/sangue , Anorexia Nervosa/complicações , Doenças do Sistema Nervoso Autônomo/complicações , Pressão Sanguínea/fisiologia , Índice de Massa Corporal , Peso Corporal , Bulimia Nervosa/sangue , Bulimia Nervosa/complicações , Feminino , Humanos , Postura/fisiologia , Teste da Mesa Inclinada
18.
Minerva Urol Nefrol ; 59(4): 455-8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17947963

RESUMO

Myelolipoma of the adrenal gland is a benign, endocrinologically inactive neoplasm composed of mature adipose tissue and a variable amount of hematopoietic elements. Rarely giant adrenal myelolipomas have been reported in literature and they are very unusual clinical entities. We describe a case in a 72 year-old woman observed at our Department of Urology for nausea, flank and abdominal pain. The surgical resected mass measured 16.5x11.5x10 cm and weighted 1 250 g. A survey of the literature on this topic is made.


Assuntos
Neoplasias das Glândulas Suprarrenais , Mielolipoma , Neoplasias das Glândulas Suprarrenais/diagnóstico , Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia , Idoso , Feminino , Humanos , Mielolipoma/diagnóstico , Mielolipoma/cirurgia , Resultado do Tratamento
19.
ACS Appl Mater Interfaces ; 8(3): 1805-12, 2016 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-26727145

RESUMO

Organic radicals are fascinating materials because of their unique properties, which make them suitable for a variety of applications. Their synthesis may be challenging, and big efforts have focused on chemical stability. However, introducing a new material in electronics not only requires chemically stable molecules but also stable monolayers and thin films in view of their use in devices. In this work, we have investigated the thin films of a derivative of the Blatter radical that was synthesized bearing in mind the thermodynamic factors that govern thin film stability. We have proved our concept by investigating the electronic structure, the paramagnetic character, and stability of the obtained films under UHV and ambient conditions by in situ X-ray photoelectron spectroscopy, ex situ atomic force microscopy, and electron paramagnetic resonance spectroscopy.

20.
J Neurosci ; 20(22): 8596-606, 2000 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11069968

RESUMO

Reduction in both presynaptic and postsynaptic structures in the aging neocortex may significantly affect functional synaptic properties in this area. To directly address this issue, we combined whole-cell patch-clamp recording of spontaneously occurring postsynaptic currents (PSCs) with morphological analysis of layer V pyramidal neurons in the parietal cortex of young adult (1- to 2-month-old) and aged (28- to 37-month-old) BN x F344 F(1) hybrid rats. Analysis of spontaneous PSCs was used to contrast functional properties of basal synaptic input with structural alterations in the dendritic tree of pyramidal neurons and density of terminals in contact with these cells. We observed significant changes in a number of morphological parameters of pyramidal neurons in aged rats. These include smaller cell body size and fewer basal dendritic branches (but not of oblique dendrites and dendritic tufts) and spines. Ultrastructural analysis also revealed a lower density of presynaptic terminals per unit length of postsynaptic membrane of labeled pyramidal neurons in the aged brain. This reduction in both presynaptic and postsynaptic elements was paralleled by a significant decrease in frequency of tetrodotoxin-insensitive miniature (action potential-independent) PSCs (mPSCs). The frequency of excitatory and inhibitory mPSCs was reduced to the same extent. In contrast, no significant change was observed in the frequency of spontaneous PSCs recorded in absence of tetrodotoxin (sPSCs), indicating an increase in action potential-dependent (frequency(sPSCs) - frequency(mPSCs)) input to pyramidal neurons in the aged group. This functional compensation may explain the lack of drastic loss of spontaneous neuronal activity in normal aging.


Assuntos
Potenciais de Ação/fisiologia , Envelhecimento/patologia , Envelhecimento/fisiologia , Neocórtex/ultraestrutura , Células Piramidais/ultraestrutura , Sinapses/ultraestrutura , Animais , Contagem de Células , Dendritos/ultraestrutura , Potenciais Pós-Sinápticos Excitadores/fisiologia , Técnicas In Vitro , Neocórtex/fisiologia , Lobo Parietal/fisiologia , Lobo Parietal/ultraestrutura , Técnicas de Patch-Clamp , Células Piramidais/fisiologia , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos F344 , Sinapses/fisiologia
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