RESUMO
The excited state dynamics of two quadrupolar polyaromatic N-methylpyridinium cations have been fully investigated in order to acquire detailed information on their photo-induced behavior. The two molecules are symmetric push-pull compounds having a D-π-A+-π-D motif, with the same electron-acceptor central unit (A = N-methylpyridinium) and two distinctive electron-donor polyaromatic side groups (D), namely naphthyl and pyrenyl substituents. Both molecules undergo charge transfer during the absorption, as revealed by a significant solvatochromism exhibited with solvent polarity, but the fate of their excited state was found to be markedly different. The careful analysis of the data gathered from femtosecond-resolved fluorescence up-conversion and transient absorption experiments, supported by DFT quantum mechanical calculations and temperature-dependent stationary measurements, shows the leading role of intramolecular charge transfer, assisted by symmetry breaking, in the pyrenyl derivative and that of rotamer interconversion in the naphthtyl one. Both excited state processes are controlled by the viscosity rather than polarity of the solvent, and they occur during inertial solvation in low-viscous media and lengthening up to tens of picoseconds in highly viscous solvents.
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The ground and excited state properties of 1-methyl-2-[(E)-2-(2-naphthyl) vinyl]pyridinium iodide have been investigated in solvents of different polarities and viscosities using stationary and ultrafast time resolved spectroscopic techniques supported by density functional theory (DFT) calculations. The investigated compound shows an important negative solvatochromism, which serves as evidence of a certain push-pull character exhibited upon photoexcitation, but the most remarkable feature is an extremely large absorption spectrum, as opposed to the narrower emission band. Interestingly, both experiments and calculations have revealed a conformational disorder in the ground state between four quasi-isoenergetic rotamers which contribute to the broad absorption spectrum. These equilibria are shifted towards one prevailing species in the excited state, pointing out an unexpected and efficient rotamer interconversion during the S1 lifetime, manifestly against the non-equilibrated excited rotamers principle. The rotamer interconversion has been found to be very fast and only hindered in a rigid matrix at low temperatures.
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Five in silico principal properties (PPs) for 218 heterocyclic cations and four PPs for 38 organic and inorganic anionic counterparts of ionic liquids (ILs) were derived by the VolSurf+ approach. VolSurf+ physicochemical descriptors take into account several cationic structural features of ILs such as heterocyclic aromatic and non-aromatic cationic cores, alkyl chain length, presence of oxygen atoms in the substituents as well as the properties of a wide variety of inorganic and organic anions. Combination of these cation and anion PPs can provide descriptors for over 8000 ILs, thus allowing the development of QSPR models for IL cytotoxicity (IPC-81 rat cell line) and enzyme toxicity (acetylcholinesterase inhibition). The adoption of a Partial Least Squares approach, relating PPs and toxicities, provided affordable predictions for ILs in both learning and external validation sets, implying the possibility to extend the predictive model to a set of 520 ILs. This allows us to establish priorities in selecting ILs for experimental hazard assessment as required by the REACH regulation.
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West Nile virus (WNV) is a zoonotic arboviral pathogen transmitted by mosquitoes in a cycle that involves wild birds as reservoir hosts. The virus is responsible for outbreaks of viral encephalitis in humans and horses. In Europe, Culex pipiens (Diptera: Culicidae) is considered to be the main vector of WNV, but other species such as Stegomyia albopicta (=Aedes albopictus) (Diptera: Culicidae) may also act as competent vectors of this virus. Since 2008 human cases of WNV disease have been reported in northeast Italy. In 2011, new areas of southern Italy became involved and a first outbreak of WNV lineage 1 occurred on the island of Sardinia. On the assumption that a potential involvement of St. albopicta in WNV transmission cannot be excluded, and in order to evaluate the competence of this species for the virus, an experimental infection of an St. albopicta laboratory colony, established from mosquitoes collected in Sardinia, was carried out. The results were compared with those obtained in a colony of the main vector Cx. pipiens. The study showed St. albopicta collected on Sardinia to be susceptible to WNV infection, which suggests this Italian mosquito species is able to act as a possible secondary vector, particularly in urban areas where the species reaches high levels of seasonal abundance.
Assuntos
Culicidae/virologia , Insetos Vetores/virologia , Vírus do Nilo Ocidental/fisiologia , Aedes/virologia , Animais , Culex/virologia , ItáliaRESUMO
A joint experimental and theoretical approach, involving state-of-the-art femtosecond fluorescence up-conversion measurements and quantum mechanical computations including vibronic effects, was employed to get a deep insight into the excited state dynamics of two cationic dipolar chromophores (Donor-π-Acceptor(+)) where the electron deficient portion is a N-methyl pyridinium and the electron donor a trimethoxyphenyl or a pyrene, respectively. The ultrafast spectroscopic investigation, and the time resolved area normalised emission spectra in particular, revealed a peculiar multiple emissive behaviour and allowed the distinct emitting states to be remarkably distinguished from solvation dynamics, occurring in water in a similar timescale. The two and three emissions experimentally detected for the trimethoxyphenyl and pyrene derivatives, respectively, were associated with specific local emissive minima in the potential energy surface of S1 on the ground of quantum-mechanical calculations. A low polar and planar Locally Excited (LE) state together with a highly polar and Twisted Intramolecular Charge Transfer (TICT) state is identified to be responsible for the dual emission of the trimethoxyphenyl compound. Interestingly, the more complex photobehaviour of the pyrenyl derivative was explained considering the contribution to the fluorescence coming not only from the LE and TICT states but also from a nearly Planar Intramolecular Charge Transfer (PICT) state, with both the TICT and the PICT generated from LE by progressive torsion around the quasi-single bond between the methylpyridinium and the ethene bridge. These findings point to an interconversion between rotamers for the pyrene compound taking place in its excited state against the Non-equilibrated Excited Rotamers (NEER) principle.
Assuntos
Elétrons , Compostos de Piridínio/química , Estrutura Molecular , Compostos de Piridínio/síntese química , Teoria Quântica , Espectrometria de FluorescênciaRESUMO
We report a case of laboratory-confirmed Zika virus infection imported into Europe from the Americas. The patient developed fever, rash, and oedema of hands and feet after returning to Italy from Brazil in late March 2015. The case highlights that, together with chikungunya virus and dengue virus, three major arboviruses are now co-circulating in Brazil. These arboviruses represent a burden for the healthcare systems in Brazil and other countries where competent mosquito vectors are present.
Assuntos
Infecção por Zika virus , Zika virus/isolamento & purificação , Anticorpos Antivirais/sangue , Brasil , Exantema/virologia , Febre/virologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Itália , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Viagem , Zika virus/genética , Zika virus/imunologia , Infecção por Zika virus/sangue , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/virologiaRESUMO
The occurrence of larval Anisakidae and Raphidascarididae in anchovies and sardines from the North Adriatic Sea has been estimated. Anisakis pegreffii and Hysterothylacium aduncum were reported, with low prevalence values. In brief, a total amount of 7650 fish specimens collected between September 2011 and 2012 were analysed using three different inspection analyses: a visual inspection of the coelomic cavity, an examination of the viscera exploiting the positive hydro-tropism of the larvae (modified Baermann technique) and enzymatic digestion of muscular tissue pools. Low level of infestation was reported for Anisakis sp. in both in anchovies and sardines, while higher values were reported for Hysterothylacium sp. Subsamples of nematodes collected were characterized at species level using the molecular diagnostic key based on ITS nuclear ribosomal region, and A. pegreffii and H. aduncum were identified. The low prevalence of Anisakis sp. in sardines and anchovies from the North Adriatic Sea could be related to the peculiar distribution of cetaceans and carnivorous zooplankton in the investigated region and could be used as a potential tag to define oily fishes from this specific fishing area as at low-risk for anisakiasis.
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Anisaquíase/epidemiologia , Infecções por Ascaridida/epidemiologia , Doenças dos Peixes/epidemiologia , Animais , Anisaquíase/parasitologia , Anisakis/genética , Infecções por Ascaridida/parasitologia , Ascaridoidea/genética , DNA Espaçador Ribossômico/genética , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Larva , Mar Mediterrâneo/epidemiologia , Prevalência , Alimentos Marinhos/parasitologiaRESUMO
We report here experimental evidence of dual emission in a cationic push-pull system (bearing a methyl pyridinium group as an electron acceptor and a diphenylamino group as an electron donor), which shows negative solvatochromism. An intriguing blue shift and enlargement of the fluorescence band upon increasing the solvent polarity have suggested a possible contribution of an upper excited state to the stationary emission. Ultrafast transient absorption has indeed revealed the presence of an intermediate transient species in some solvents. The investigation of the fluorescence properties at low temperatures and in the rigid matrix has given a clear indication of this additional emission at shorter wavelengths. Femtosecond up-conversion measurements have shown interesting rise-decay dynamics in the kinetics and two well distinguished emission bands characterized by different deactivations. A single isoemissive point in the time-resolved area-normalized spectra has unambiguously pointed out the presence of two consecutive emissive species: the locally excited and the intramolecular charge transfer excited states.
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Levels of 24 organochlorine compounds, including toxic mono-ortho PCB congeners, were determined in the organs and tissues (blubber, kidney, lung, muscle, liver, heart) of 13 common bottlenose dolphins (Tursiops truncatus) stranded between 2000 and 2005 in the northern part of the Croatian territorial waters of the Adriatic Sea. Polychlorinated biphenyls (PCBs) were found at higher concentrations in comparison with organochlorine pesticides (OCPs) in all of the analyzed tissues. Sums of six indicator congeners (Σ6PCB) constituted around 50% of the total PCB amount, while PCB-153 and PCB-138 were found to have the highest concentrations. Among the seven investigated OCPs, p,p'-DDE was found at the highest concentrations. In blubber, mean values of 22,048 and 11,310ngg(-1) wet weight were determined for ΣPCB and ΣDDT, respectively. Much lower concentrations were found in muscle samples, followed by similar concentrations in kidneys, liver and heart, while the lowest levels of organochlorine contaminants were found in lungs. The results indicate that p,p'-DDT is still being introduced in the Mediterranean region. PCB concentrations are among the highest found in this region and toxicological assessments indicate that the health of this specie is at high risk.
Assuntos
Golfinho Nariz-de-Garrafa/fisiologia , Monitoramento Ambiental/métodos , Praguicidas/metabolismo , Bifenilos Policlorados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Golfinho Nariz-de-Garrafa/classificação , Golfinho Nariz-de-Garrafa/crescimento & desenvolvimento , Croácia , Feminino , Rim/química , Fígado/química , Pulmão/química , Masculino , Músculos/química , Miocárdio/química , Praguicidas/análise , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análiseRESUMO
In 2011, from 26 September to 16 October, a small outbreak of West Nile virus (WNV) disease occurred on the island of Sardinia (Italy). According to the national case definition, six cases with acute neurological disease were confirmed in hospitalized patients, and four of them died; one of these was only 34 years old. In two case, WNV RNA was detected in urine, suggesting renal involvement. Sequence analysis showed lineage 1 and 2 circulation.
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Surtos de Doenças , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/classificação , Vírus do Nilo Ocidental/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Genótipo , Humanos , Itália/epidemiologia , Masculino , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de DNA , Urina/virologia , Febre do Nilo Ocidental/mortalidade , Vírus do Nilo Ocidental/isolamento & purificaçãoRESUMO
A brief review of the arboviruses isolated In Italy is presented and discussed. Some of the Arboviruses considered in this paper are endemic in the country and are transmitted by arthropods that play actually a role of vectors, (sand flyes, hard ticks and mosquitoes); other arboviruses, sporadically isolated, are potential agents of emerging human or zoonotic diseases.
Assuntos
Infecções por Arbovirus/epidemiologia , Arbovírus/isolamento & purificação , Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/transmissão , Animais , Infecções por Arbovirus/transmissão , Infecções por Arbovirus/veterinária , Doenças das Aves/epidemiologia , Doenças das Aves/virologia , Aves/virologia , Vírus Chikungunya , Reservatórios de Doenças , Vírus da Encefalite Transmitidos por Carrapatos , Encefalite Transmitida por Carrapatos/epidemiologia , Encefalite Transmitida por Carrapatos/transmissão , Encefalite Transmitida por Carrapatos/virologia , Humanos , Itália/epidemiologia , Ixodes/virologia , Murinae/parasitologia , Phlebotomus/virologia , Rhipicephalus/virologia , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/transmissão , Febre do Nilo Ocidental/veterinária , Vírus do Nilo OcidentalRESUMO
BACKGROUND: Chikungunya virus (CHIKV), which is transmitted by Aedes spp mosquitoes, has recently caused several outbreaks on islands in the Indian Ocean and on the Indian subcontinent. We report on an outbreak in Italy. METHODS: After reports of a large number of cases of febrile illness of unknown origin in two contiguous villages in northeastern Italy, an outbreak investigation was done to identify the primary source of infection and modes of transmission. An active surveillance system was also implemented. The clinical case definition was presentation with fever and joint pain. Blood samples were gathered and analysed by PCR and serological assays to identify the causal agent. Locally captured mosquitoes were also tested by PCR. Phylogenetic analysis of the CHIKV E1 region was done. FINDINGS: Analysis of samples from human beings and from mosquitoes showed that the outbreak was caused by CHIKV. We identified 205 cases of infection with CHIKV between July 4 and Sept 27, 2007. The presumed index case was a man from India who developed symptoms while visiting relatives in one of the villages. Phylogenetic analysis showed a high similarity between the strains found in Italy and those identified during an earlier outbreak on islands in the Indian Ocean. The disease was fairly mild in nearly all cases, with only one reported death. INTERPRETATION: This outbreak of CHIKV disease in a non-tropical area was to some extent unexpected and emphasises the need for preparedness and response to emerging infectious threats in the era of globalisation.
Assuntos
Aedes/virologia , Infecções por Alphavirus/epidemiologia , Vírus Chikungunya/patogenicidade , Surtos de Doenças , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções por Alphavirus/fisiopatologia , Animais , Vírus Chikungunya/isolamento & purificação , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , ViagemRESUMO
Three clusters of measles cases occurred between June and September 2006, in the Roma/Sinti populations in three different Italian regions: the Bolzano-South Tyrol in northern Italy; Lazio in central Italy; and the island of Sardinia in the southwest.
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Surtos de Doenças/estatística & dados numéricos , Sarampo/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Análise por Conglomerados , Doenças em Gêmeos , Feminino , Humanos , Lactente , Transmissão de Doença Infecciosa do Paciente para o Profissional , Itália/epidemiologia , Masculino , Sarampo/transmissão , Vacina contra Sarampo , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Roma (Grupo Étnico) , Romênia/etnologia , Cidade de Roma/epidemiologia , VacinaçãoRESUMO
Experimental studies have highlighted the potential influence of contaminants on marine mammal immune function and anthropogenic contaminants are commonly believed to influence the development of diseases observed in the wild. However, estimates of the impact of contaminants on wild populations are constrained by uncertainty over natural variation in disease patterns under different environmental conditions. We used photographic techniques to compare levels of epidermal disease in ten coastal populations of bottlenose dolphins (Tursiops truncatus) exposed to a wide range of natural and anthropogenic conditions. Epidermal lesions were common in all populations (affecting > 60% of individuals), but both the prevalence and severity of 15 lesion categories varied between populations. No relationships were found between epidermal disease and contaminant levels across the four populations for which toxicological data were available. In contrast, there were highly significant linear relationships with oceanographic variables. In particular, populations from areas of low water temperature and low salinity exhibited higher lesion prevalence and severity. Such conditions may impact on epidermal integrity or produce more general physiological stress, potentially making animals more vulnerable to natural infections or anthropogenic factors. These results show that variations in natural environmental factors must be accounted for when investigating the importance of anthropogenic impacts on disease in wild marine mammals.
Assuntos
Golfinhos , Dermatopatias/veterinária , Animais , Exposição Ambiental/efeitos adversos , Prevalência , Dermatopatias/epidemiologia , Dermatopatias/etiologia , Dermatopatias/fisiopatologiaRESUMO
A multiprofessional experience carried out during a pedagogic course for health professionals, most of them dentists, to act on the in-service formation of middle level personnel is reported. The course was developed in group, and its task was to learn the problem posing pedagogy. The study was analyzed according to the Pichon-Rivière's theoretical framework. Data analysis has evidenced the close relationship among operativeness and the explicitness of the human relations ghosts, learning difficulties and communication disorders, evidencing the interdependence among communication and learning.
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Comunicação , Educação Continuada/organização & administração , Processos Grupais , Relações Interprofissionais , Equipe de Assistência ao Paciente/organização & administração , Humanos , Modelos Educacionais , Resolução de ProblemasRESUMO
The present study aims at reporting the experience of construction of an interinstitutional relationship: university and health services, pointing out the possibilities and difficulties of the process.
Assuntos
Serviços de Saúde , Relações Interprofissionais , Universidades , HumanosRESUMO
Pyogenic abscess of the liver is uncommon child's pathology. The authors briefly describe a clinical picture characterized by beginning of an hepatic abscess dues to a germ that is not usually pathogen for men. It is often a mouth saprophyte.
Assuntos
Abscesso Hepático/microbiologia , Streptococcus/isolamento & purificação , Criança , Humanos , Abscesso Hepático/tratamento farmacológico , Masculino , Penicilina G/administração & dosagem , Penicilina G/uso terapêuticoRESUMO
The purpose of this work is to evaluate an alternative methodology of education in adult health care undertaken with health care workers. The evaluation was made by the directional question: what did the Adult Health Course mean to you? The analysis consisted of detecting in the responses, the affirmatives that were respective and grouping them in seven categories: 01. Learning new things. 02. Learning to orient people who goes to the basic Health Unit. 03. Interaction with colleagues. 04. Feeling professionally appraned. 05. Worrisome with sons. 06. Improving way of life. 07. Suggestions. The results refers to the presuppositions presented in the introduction of the article, as well as, with the Epidemiologic Model proposed by BLUM.