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1.
J Neural Eng ; 14(1): 011001, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28068295

RESUMO

Support vector machines (SVMs) are widely used classifiers for detecting physiological patterns in human-computer interaction (HCI). Their success is due to their versatility, robustness and large availability of free dedicated toolboxes. Frequently in the literature, insufficient details about the SVM implementation and/or parameters selection are reported, making it impossible to reproduce study analysis and results. In order to perform an optimized classification and report a proper description of the results, it is necessary to have a comprehensive critical overview of the applications of SVM. The aim of this paper is to provide a review of the usage of SVM in the determination of brain and muscle patterns for HCI, by focusing on electroencephalography (EEG) and electromyography (EMG) techniques. In particular, an overview of the basic principles of SVM theory is outlined, together with a description of several relevant literature implementations. Furthermore, details concerning reviewed papers are listed in tables and statistics of SVM use in the literature are presented. Suitability of SVM for HCI is discussed and critical comparisons with other classifiers are reported.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia/métodos , Eletromiografia/métodos , Sistemas Homem-Máquina , Reconhecimento Automatizado de Padrão/métodos , Máquina de Vetores de Suporte , Algoritmos , Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Humanos , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Robótica/métodos
2.
Euro Surveill ; 19(48): 20978, 2014 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-25496572

RESUMO

Toscana virus (TOSV), transmitted by phlebotomine sandflies, is recognised as one of the most important causes of viral meningitis in summer in Mediterranean countries. A surveillance plan based on both human and entomological surveys was started in 2010 in the Emilia-Romagna region, Italy. Clinical samples from patients with neurological manifestations were collected during 2010 to 2012. The surveillance protocol was improved during these years, allowing the detection of 65 human infections. Most of these infections were recorded in hilly areas, where sandflies reach the highest density. Entomological sampling around the homes of the patients resulted in a low number of captured sandflies, while later sampling in a hilly area with high number of human cases (n=21) resulted in a larger number of captured sandflies. Using this approach, 25,653 sandflies were sampled, of which there were 21,157 females, which were sorted into 287 pools. TOSV RNA was detected by real-time PCR in 33 of the pools. The results highlighted the role of Phlebotomus perfiliewi as the main vector of TOSV and a potential link between vector density and virus circulation. This integrated system shows that an interdisciplinary approach improves the sensitiveness and effectiveness of health surveillance.


Assuntos
Vigilância da População , Psychodidae/virologia , RNA Viral/genética , Vírus da Febre do Flebótomo Napolitano/isolamento & purificação , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Genótipo , Humanos , Imunoglobulina G , Imunoglobulina M , Insetos Vetores/virologia , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vírus da Febre do Flebótomo Napolitano/classificação , Vírus da Febre do Flebótomo Napolitano/genética , Análise de Sequência de DNA , Distribuição por Sexo , Adulto Jovem
3.
Clin Microbiol Infect ; 18(6): 558-64, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21966997

RESUMO

Neisseria gonorrhoeae resistance to cephalosporins, the currently recommended treatment, and treatment failures with cefixime have been reported worldwide. The purposes of the present study were (i) to examine the susceptibility of N. gonorrhoeae isolates isolated in Italy from 2006 through 2010 to cefixime (n = 293) taking into account both European Committee on Antimicrobial Susceptibility Testing (EUCAST) and Clinical And Laboratory Standards Institute (CLSI) criteria for categorization; (ii) to determine the contribution to decreased/resistant susceptibility of mutations in the penA, mtrR, ponA and porB1b genes in a subsample of isolates; and (iii) to genotype the isolates showing decreased susceptibility or resistance to cefixime, by N. gonorrhoeae multi-antigen sequence typing (NG-MAST) and by pulsed-field gel electrophoresis (PFGE) to identify the predominant genotypes. Minimum inhibitory concentrations (MICs) were determined by the E-test and agar dilution method on 293 isolates and results were interpreted according to both EUCAST 2010 (MIC R >0.12 mg/L) and CLSI 2008 (MIC R >0.25 mg/L) criteria. All isolates showed full susceptibility to ceftriaxone, whereas those with a MIC for cefixime ≥0.125 mg/L were on the increase from 2008 through 2010. The same penA gene alterations were found among isolates with MICs close to the EUCAST breakpoint as the resistant ones, and they belong to ST1407. Seven isolates, belonging to various sequence types, showed a different por allele, though similar to the por 908 allele present in ST1407. PFGE divided strains ST1407 into two main groups confirming their genetic relationship.


Assuntos
Antibacterianos/farmacologia , Cefixima/farmacologia , Ceftriaxona/farmacologia , Neisseria gonorrhoeae/efeitos dos fármacos , Neisseria gonorrhoeae/isolamento & purificação , Proteínas de Bactérias/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Eletroforese em Gel de Campo Pulsado , Genótipo , Humanos , Itália , Masculino , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Tipagem Molecular , Proteínas Mutantes/genética , Neisseria gonorrhoeae/classificação , Neisseria gonorrhoeae/genética , Análise de Sequência de DNA
4.
Clin Microbiol Infect ; 17(9): 1349-52, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21745260

RESUMO

Dengue is a significant mosquito-borne infection in humans, and its worldwide prevalence is rapidly increasing. In 2010, 83 serum samples from febrile travellers returning from dengue-endemic countries to a region in north-eastern Italy, densely infested with Aedes albopictus, were analysed for dengue virus (DENV). DENV RNA was detected in 20.5% of patients. By RT-PCR, DENV serotypes 1 and 3 were the most common. DENV must be identified early in symptomatic travellers returning from high-risk countries, to prevent outbreaks where potential vectors exist.


Assuntos
Vírus da Dengue/isolamento & purificação , Dengue/epidemiologia , Adolescente , Adulto , Animais , Anticorpos Antivirais/sangue , Criança , Chlorocebus aethiops , Dengue/transmissão , Dengue/virologia , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Vigilância da População , RNA Viral , Reação em Cadeia da Polimerase em Tempo Real , Viagem , Células Vero , Proteínas não Estruturais Virais/genética
6.
Euro Surveill ; 15(16)2010 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-20430000

RESUMO

Following a large West Nile virus (WNV) epidemic in northeastern Italy in 2008, human and animal surveillance activities were implemented in Emilia Romagna. Human surveillance was performed by serology or genome detection on blood and cerebrospinal fluid for all suspected cases suffering from acute meningoencephalitis in the regional territory. Animal surveillance consisted of passive and active surveillance of horses and active surveillance of wild birds and mosquitoes. Between 15 June and 31 October 2009, nine of 78 possible cases of West Nile neuroinvasive disease were confirmed (three fatal). From May to October, 26 cases of neurological West Nile disease were confirmed among 46 horses. The overall incidence of seroconversion among horses in 2009 was 13%. In 2009, 44 of 1,218 wild birds yielded positive PCR results for WNV infection. The planned veterinary and entomological surveillance actions detected WNV activity from the end of July 2009, about 2-3 weeks before the onset of the first human neurological case. Passive surveillance of horses seems to be an early and suitable tool for the detection of WNV activity, but it will be less sensitive in the future, because an intensive programme of horse vaccination started in June 2009.


Assuntos
Surtos de Doenças/prevenção & controle , Surtos de Doenças/estatística & dados numéricos , Vigilância da População/métodos , Medição de Risco/métodos , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/prevenção & controle , Vírus do Nilo Ocidental/isolamento & purificação , Humanos , Incidência , Itália/epidemiologia , Fatores de Risco
7.
J Dent Res ; 89(5): 521-6, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20200417

RESUMO

Treponema denticola has been identified as an important cause of periodontal disease and hypothesized to be involved in extra-oral infections. The objective of this study was to investigate the role of T. denticola cell length and motility during mouse peritoneal macrophages in vitro uptake. Macrophages, incubated under aerobic and anaerobic conditions, produced a similar amount of TNF-alpha when stimulated with Escherichia coli LPS. The uptake of FlgE- and CfpA-deficient mutants of T. denticola was significantly increased compared with the wild-type strain, due to cell size or lack of motility. Opsonization with specific antibodies considerably improved the treponemes' uptake. These results suggest that macrophages, in addition to other phagocytes, could play an important role in the control of T. denticola infection, and that the raising of specific antibodies could improve the efficacy of the immune response toward T. denticola, either at an oral site or during dissemination.


Assuntos
Macrófagos Peritoneais/imunologia , Fagocitose/imunologia , Treponema denticola/imunologia , Aerobiose , Anaerobiose , Animais , Anticorpos Antibacterianos/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Células Cultivadas , Proteínas do Citoesqueleto/genética , Escherichia coli , Técnica Indireta de Fluorescência para Anticorpo , Imunoglobulina E/genética , Lipopolissacarídeos/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Proteínas de Membrana/imunologia , Camundongos , Mutação/genética , Treponema denticola/genética , Fator de Necrose Tumoral alfa/análise
8.
Euro Surveill ; 14(50)2009 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-20070935

RESUMO

We report a case of Usutu virus (USUV)-related illness in a patient that underwent an orthotropic liver transplant (OLT). Post transplant, the patient developed clinical signs of a possible neuroinvasive disease with a significant loss of cerebral functions. USUV was isolated in Vero E6 cells from a plasma sample obtained immediately before the surgery, and USUV RNA was demonstrated by RT-PCR and sequencing. This report enlarges the panel of emerging mosquito-borne flavivirus-related disease in humans.


Assuntos
Infecções por Flavivirus/diagnóstico , Flavivirus/isolamento & purificação , Transplante de Fígado , Adulto , Feminino , Flavivirus/genética , Infecções por Flavivirus/etiologia , Humanos , Itália , Transplante de Fígado/efeitos adversos , Pessoa de Meia-Idade
11.
Oral Microbiol Immunol ; 20(5): 289-95, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16101964

RESUMO

BACKGROUND/AIMS: The presence of selected bacteria (Enterococcus faecalis, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis, Treponema denticola) in infected root canals was studied using polymerase chain reaction (PCR) assays, and the association of bacteria with clinical signs of endodontic disease was assessed. The null hypothesis, that no difference could be observed between clinical signs of apical periodontitis and a specific bacterial strain, was tested. METHODS: Microbial samples were obtained from 62 teeth in 54 patients with endodontic disease. For each tooth, clinical data including patient symptoms were collected. Teeth were categorized by diagnosis as having acute apical periodontitis (AAP, teeth with clinical symptoms but no periapical radiolucency, n=22), chronic apical periodontitis (CAP, teeth with radiolucency but no clinical symptoms, n=15) or exacerbated apical periodontitis (EAP, teeth with symptoms and radiolucency, n=25). Seventy-one percent of cases were primary endodontic infections, and 29% were recurrent ('secondary') endodontic infections (failing cases). PCR assays were used to detect the presence of the selected bacteria. RESULTS: T. denticola and E. faecalis were each detected in 15 of 62 samples (24%), P. gingivalis in 8 samples (13%), P. intermedia in 5 samples (8%), and T. forsythensis in 4 samples (7%). T. denticola was detected in 56% of teeth with EAP. E. faecalis was found in 60% of teeth with CAP and in 72% of teeth with secondary infection. Statistical analysis demonstrated an association of CAP and secondary endodontic infection with the presence of E. faecalis. (P<0.01). EAP was associated with the presence of T. denticola (P<0.01). CONCLUSION: T. denticola was associated with symptomatic endodontic disease in the presence of apical bone resorption. E. faecalis was associated with treatment failures. We suggest that these species may play critical roles in endodontic pathology.


Assuntos
Bactérias/isolamento & purificação , Cavidade Pulpar/microbiologia , Doenças da Polpa Dentária/microbiologia , Periodontite Periapical/microbiologia , Reação em Cadeia da Polimerase , Adulto , Idoso , Bactérias/classificação , Infecções por Bacteroidaceae/microbiologia , Bacteroides/isolamento & purificação , Infecções por Bacteroides/microbiologia , Reabsorção Óssea/microbiologia , Enterococcus faecalis/isolamento & purificação , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Itália , Pessoa de Meia-Idade , Doenças Periapicais/microbiologia , Porphyromonas gingivalis/isolamento & purificação , Prevotella intermedia/isolamento & purificação , Treponema denticola/isolamento & purificação , Infecções por Treponema/microbiologia
12.
Parassitologia ; 46(1-2): 109-13, 2004 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-15305697

RESUMO

Tick-borne zoonotic infections are among the most diffuse vector borne diseases: these large group of infections is caused by different microorganisms: Babesia spp., Borrelia spp., Rickettsia spp., Ehrlichia spp., Francisella tularensis, Coxiella burnetii) and tick-borne encephalitis virus. Babesiosis is caused by the protozoa (sporozoa) Babesia microti and it is quite rare in humans in Europe. The ixodids ticks are the competent vectors. A few symptomatic cases have been reported, mainly in splenectomized patients. The laboratory diagnosis is made by the microscopic identification of the parasites within the red blood cells in blood smears. The serologic diagnosis, based mainly upon IFA and WB techniques has only an epidemiological interest. Lyme borreliosis (Lyme disease) has been recognized as the most frequent vector borne disease in mild climate areas. The etiologic agent is a spirochete, belonging to the Borrelia burgdorferi sensu lato complex: B. burgdorferi sensu stricto, B. garinii and B. afzelii. Several additional species of this geno-complex have been identified but their pathogenic capability for humans still needs to be elucidated. Lyme borreliosis is clinically divided into three different clinical stages: the early disease, the disseminated infection and the persistent infection. Individual stages are caused by the diffusion of the spirochetes to different anatomic districts of the body. The main clinical symptoms are, for each stage: the erythema chronicum migrans in the early infection, the peripheral nerves and joint involvement in disseminated diseases and the acrodermatitis chronica atrophica (ACA) with central nervous system involvement in the late disseminated infection. The microbiological diagnosis is achieved by serologic techniques (IFA, EIA, WB) and by isolation of the spirochetes (in vitro culture and DNA amplification methods). Tick-borne relapsing fever (TBRF) is occasionally transmitted to humans by the soft ticks Ornithodorus and is caused by Borrelia spp. Different borreliae are responsible for TBRF in various geographic areas. The laboratory diagnosis is based upon the identification of spirochetes in peripheral blood by microscopic observation of Giemsa stained smears. Rickettsiosis diseases are caused worldwide by the obligate intracellular bacteria belonging to the genus Rickettsia. In the Mediterranean area the most frequently identified rickettsia is R. conorii, that causes the so called Mediterranean spotted fever. The serologic detection of a specific antibody response by IFA techniques is the most prominent tool for the diagnosis. In addition, the PCR method can be applied. Bacteria of the genus Ehrlichia are well known pathogens in veterinary medicine. Since the last decade their zoonotic capability has emerged and E. chafeensis, E. canis and the so called human granulocytic agent (HGE) have been identified in human diseases following a tick bite. The ehrlichiosis is characterized, in human, by a mild fever associated with lymphoadenopathy. The diagnosis is made on the identification of morulae (the intracytoplasmatic inclusion of the growing rickettsiae) in the white cells of peripheral blood. In addition the molecular diagnosis is also possible by PCR. Tick-borne encephalitis (TBE) is the only viral arthropod-borne encephalitis in Europe: it is caused by a flavivirus and it can also be transmitted by the ingestion of goat raw milk. The more relevant epidemiological figure is limited to the Alps, in particular to the Northern side (Austria). Isolated cases have been reported also in Italy. TBE is a benign self-limiting illness that usually recovers without any reliquate. The laboratory diagnosis is obtained by isolating the virus in cell cultures from the CSF or blood of acute phase patients. Serology is anyway the main laboratory tool to perform this diagnosis. Complement fixation and EIA IgM are the most used methods: the latter technique is particularly sensitive in early infection.


Assuntos
Doenças Transmitidas por Carrapatos/diagnóstico , Zoonoses , Animais , Animais Domésticos/parasitologia , Vetores Aracnídeos/microbiologia , Vetores Aracnídeos/parasitologia , Vetores Aracnídeos/virologia , Babesiose/diagnóstico , Babesiose/transmissão , Babesiose/veterinária , Bacteriemia/diagnóstico , Bacteriemia/transmissão , Europa (Continente)/epidemiologia , Humanos , Doença de Lyme/diagnóstico , Doença de Lyme/transmissão , Parasitemia/diagnóstico , Parasitemia/transmissão , Doenças Parasitárias em Animais/epidemiologia , Doenças Parasitárias em Animais/transmissão , Testes Sorológicos , Doenças Transmitidas por Carrapatos/epidemiologia , Carrapatos/microbiologia , Carrapatos/parasitologia , Carrapatos/virologia , Viremia/diagnóstico , Viremia/transmissão , Zoonoses/epidemiologia
13.
New Microbiol ; 27(4): 391-7, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15646054

RESUMO

Direct person-to-person transmission of periodontal bacteria through saliva has recently been widely reported and dental units have been demonstrated to retract saliva from patients under treatment and to release it into the mouths of subjects undergoing the next operation. In this study the presence of a group of periodontal pathogenic bacteria inside waterlines in dental units was investigated using polymerase chain reaction (PCR) based methods. Briefly, 18 dental units of three different manufacturers were studied. Dental units were divided into two groups according to their prevalent use in routine practice. The first group consisted of nine dental units characterized by the frequent use of high-speed dental hand-pieces directly inside the mouth and in contact with patients' saliva. The second group, as a control, consisted of nine dental units where high-speed dental hand-pieces were not in use. A one cm section of the waterline tubing connected to the high-speed hand-piece was removed from each dental unit to evaluate the presence of DNA of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Bacteroides forsythus, Treponema denticola. Two specimens were positive for Prevotella intermedia DNA. All the positive results were from samples obtained from dental units categorised in the first group. These findings clearly suggest that dental units have the potential to transmit periodontal pathogens. Manufacturers should be invited to design dental units that incorporate automated devices to disinfect DUWLs between patients with minimal effort by dental staff.


Assuntos
Bactérias/isolamento & purificação , Biofilmes/crescimento & desenvolvimento , DNA Bacteriano/análise , Equipamentos Odontológicos/microbiologia , Contaminação de Equipamentos , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Aggregatibacter actinomycetemcomitans/isolamento & purificação , Bacteroides/crescimento & desenvolvimento , Bacteroides/isolamento & purificação , Humanos , Doenças Periodontais/microbiologia , Reação em Cadeia da Polimerase , Porphyromonas gingivalis/crescimento & desenvolvimento , Porphyromonas gingivalis/isolamento & purificação , Prevotella intermedia/crescimento & desenvolvimento , Prevotella intermedia/isolamento & purificação , Treponema denticola/crescimento & desenvolvimento , Treponema denticola/isolamento & purificação
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