927 resultados para HUMAN-HERPESVIRUS-8 INFECTION


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A prática do ioga tem se tornado cada vez mais popular, não apenas pelos benefícios físicos, mas principalmente pelo bem-estar psicológico trazido pela sua prática. Um dos componentes do ioga é o Prãnãyama, ou controle da respiração. A atenção e a respiração são dois mecanismos fisiológicos e involuntários requeridos para a execução do Prãnãyama. O principal objetivo desse estudo foi verificar se variáveis contínuas do EEG (potência de diferentes faixas que o compõem) seriam moduladas pelo controle respiratório, comparando-se separadamente as duas fases do ciclo respiratório (inspiração e expiração), na situação de respiração espontânea e controlada. Fizeram parte do estudo 19 sujeitos (7 homens/12 mulheres, idade média de 36,89 e DP = ± 14,46) que foram convidados a participar da pesquisa nas dependências da Faculdade de Saúde da Universidade Metodista de São Paulo. Para o registro do eletroencefalograma foi utilizado um sistema de posicionamento de cinco eletrodos Ag AgCl (FPz, Fz, Cz, Pz e Oz) fixados a uma touca de posicionamento rápido (Quick-Cap, Neuromedical Supplies®), em sistema 10-20. Foram obtidos valores de máxima amplitude de potência (espectro de potência no domínio da frequência) nas frequências teta, alfa e beta e delta e calculada a razão teta/beta nas diferentes fases do ciclo respiratório (inspiração e expiração), separadamente, nas condições de respiração espontânea e de controle respiratório. Para o registro do ciclo respiratório, foi utilizada uma cinta de esforço respiratório M01 (Pletismógrafo). Os resultados mostram diferenças significativas entre as condições de respiração espontânea e de controle com valores das médias da razão teta/beta menores na respiração controlada do que na respiração espontânea e valores de média da potência alfa sempre maiores no controle respiratório. Diferenças significativas foram encontradas na comparação entre inspiração e expiração da respiração controlada com diminuição dos valores das médias da razão teta/beta na inspiração e aumento nos valores das médias da potência alfa, sobretudo na expiração. Os achados deste estudo trazem evidências de que o controle respiratório modula variáveis eletrofisiológicas relativas à atenção refletindo um estado de alerta, porém mais relaxado do que na situação de respiração espontânea.

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Background: Proton Magnetic Resonance Spectroscopy (H-MRS) is a non-invasive imaging technique that enables quantification of neurochemistry in vivo and thereby facilitates investigation of the biochemical underpinnings of human cognitive variability. Studies in the field of cognitive spectroscopy have commonly focused on relationships between measures of N-acetyl aspartate (NAA), a surrogate marker of neuronal health and function, and broad measures of cognitive performance, such as IQ. Methodology/Principal Findings: In this study, we used H-MRS to interrogate single-voxels in occipitoparietal and frontal cortex, in parallel with assessments of psychometric intelligence, in a sample of 40 healthy adult participants. We found correlations between NAA and IQ that were within the range reported in previous studies. However, the magnitude of these effects was significantly modulated by the stringency of data screening and the extent to which outlying values contributed to statistical analyses. Conclusions/Significance: H-MRS offers a sensitive tool for assessing neurochemistry non-invasively, yet the relationships between brain metabolites and broad aspects of human behavior such as IQ are subtle. We highlight the need to develop an increasingly rigorous analytical and interpretive framework for collecting and reporting data obtained from cognitive spectroscopy studies of this kind. © 2014 Patel, Blyth, Griffiths, Kelly and Talcott.

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Altered state theories of hypnosis posit that a qualitatively distinct state of mental processing, which emerges in those with high hypnotic susceptibility following a hypnotic induction, enables the generation of anomalous experiences in response to specific hypnotic suggestions. If so then such a state should be observable as a discrete pattern of changes to functional connectivity (shared information) between brain regions following a hypnotic induction in high but not low hypnotically susceptible participants. Twenty-eight channel EEG was recorded from 12 high susceptible (highs) and 11 low susceptible (lows) participants with their eyes closed prior to and following a standard hypnotic induction. The EEG was used to provide a measure of functional connectivity using both coherence (COH) and the imaginary component of coherence (iCOH), which is insensitive to the effects of volume conduction. COH and iCOH were calculated between all electrode pairs for the frequency bands: delta (0.1-3.9 Hz), theta (4-7.9 Hz) alpha (8-12.9 Hz), beta1 (13-19.9 Hz), beta2 (20-29.9 Hz) and gamma (30-45 Hz). The results showed that there was an increase in theta iCOH from the pre-hypnosis to hypnosis condition in highs but not lows with a large proportion of significant links being focused on a central-parietal hub. There was also a decrease in beta1 iCOH from the pre-hypnosis to hypnosis condition with a focus on a fronto-central and an occipital hub that was greater in high compared to low susceptibles. There were no significant differences for COH or for spectral band amplitude in any frequency band. The results are interpreted as indicating that the hypnotic induction elicited a qualitative change in the organization of specific control systems within the brain for high as compared to low susceptible participants. This change in the functional organization of neural networks is a plausible indicator of the much theorized "hypnotic-state". © 2014 Jamieson and Burgess.

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Neuroimaging (NI) technologies are having increasing impact in the study of complex cognitive and social processes. In this emerging field of social cognitive neuroscience, a central goal should be to increase the understanding of the interaction between the neurobiology of the individual and the environment in which humans develop and function. The study of sex/gender is often a focus for NI research, and may be motivated by a desire to better understand general developmental principles, mental health problems that show female-male disparities, and gendered differences in society. In order to ensure the maximum possible contribution of NI research to these goals, we draw attention to four key principles—overlap, mosaicism, contingency and entanglement—that have emerged from sex/gender research and that should inform NI research design, analysis and interpretation. We discuss the implications of these principles in the form of constructive guidelines and suggestions for researchers, editors, reviewers and science communicators.

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Multiple transformative forces target marketing, many of which derive from new technologies that allow us to sample thinking in real time (i.e., brain imaging), or to look at large aggregations of decisions (i.e., big data). There has been an inclination to refer to the intersection of these technologies with the general topic of marketing as “neuromarketing”. There has not been a serious effort to frame neuromarketing, which is the goal of this paper. Neuromarketing can be compared to neuroeconomics, wherein neuroeconomics is generally focused on how individuals make “choices”, and represent distributions of choices. Neuromarketing, in contrast, focuses on how a distribution of choices can be shifted or “influenced”, which can occur at multiple “scales” of behavior (e.g., individual, group, or market/society). Given influence can affect choice through many cognitive modalities, and not just that of valuation of choice options, a science of influence also implies a need to develop a model of cognitive function integrating attention, memory, and reward/aversion function. The paper concludes with a brief description of three domains of neuromarketing application for studying influence, and their caveats.

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Entre las actividades de ocio de los/as jóvenes, cabe mencionar las asociadas con los videojuegos. Por ello, la finalidad central de este estudio es analizar las preferencias del colectivo de adolescentes con los videojuegos, así como conocer su dedicación y problemáticas que generan, teniendo en cuenta principalmente la variable de género. El presente trabajo se encuadra en un enfoque metodológico cuantitativo-cualitativo, a partir de la recogida de datos con un cuestionario y la técnica del grupo de discusión. En el estudio han participado un total de 151 adolescentes. 124 a partir de la aplicación de un cuestionario cerrado (62 hombres y 62 mujeres) y 27 a través de la realización de 6 grupos de discusión (17 hombres y 10 mujeres). Como resultados y conclusiones, cabe destacar la existencia diferenciada en el uso de los videojuegos en función de la edad y por razón de género. A su vez, las mujeres muestran una responsabilidad mayor en esta actividad, tanto en el tiempo de dedicación como en la elección. Los chicos destinan una gran cantidad de tiempo a los videojuegos de contenido violento, mientras las chicas prefieren los de estrategia. En general, el juego con videojuegos no genera problemáticas sustanciales y controversias, aunque algunos participantes reflejan manifestaciones de mal humor. Por último, cabe indicar que las prácticas con los videojuegos en la adolescencia se ciñen al mero hecho de divertirse, desperdiciando las posibilidades educativas que esta actividad ofrece.

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Introdução: A tuberculose miliar resulta da disseminação linfohematogénica do Mycobacterium tuberculosis, sendo uma manifestação grave da infeção. Caso clínico: Criança de 9 anos, género feminino, com his¬tória de febre prolongada. O diagnóstico de tuberculose miliar foi colocado após telerradiografia torácica com infiltrado reticu¬lonodular difuso bilateral, e corroborado pelo achado de tubér¬culos coroideus no olho direito e visualização de bacilos álcool¬ ¬ácido resistentes em amostra de suco gástrico. Detetaram¬-se tuberculomas cerebrais na ressonância magnética. Isolou¬se Mycobacterium tuberculosis multissensível em amostras de suco gástrico. Após mais de 40 dias de tratamento, persistia a febre e baciloscopia positiva. Foi excluída infeção pelo vírus da imunodeficiência humana. Não foram detetadas complicações. Posteriormente, a evolução clínica foi favorável. Discussão/Conclusão: A tuberculose mantém-¬se um diag¬nóstico relevante na criança com febre prolongada. A associa¬ção da imagem torácica, baciloscopias positivas e tubérculos coroideus foram fundamentais para a celeridade do diagnóstico e implementação do tratamento. Reforça¬-se a importância de manter elevado índice de suspeição para uma patologia que tem tratamento.

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Einleitung: Notwendige Voraussetzung für die Entstehung von Zervixkarzinomen ist eine persistierende Infektion mit humanen Papillomaviren (HPV). Die HPV-Typen 16 und 18 verursachen mit etwa 70% den überwiegenden Teil der Zervixkarzinome. Seit 2006/2007 stehen zwei Impfstoffe gegen HPV 16 und 18 zur Verfügung. Fragestellung: Wie effektiv ist die HPV-Impfung hinsichtlich der Reduktion von Zervixkarzinomen bzw. ihren Vorstufen (CIN)? Stellt die HPV-Impfung eine kosteneffektive Ergänzung zur derzeitigen Screeningpraxis dar? Gibt es Unterschiede bezüglich der Kosten-Effektivität zwischen den beiden verfügbaren Impfstoffen? Sollte aus gesundheitsökonomischer Perspektive eine Empfehlung für den Einsatz der HPV-Impfung gegeben werden? Falls ja, welche Empfehlungen bezüglich der Ausgestaltung einer Impfstrategie lassen sich ableiten? Welche ethischen, sozialen und juristischen Implikationen sind zu berücksichtigen? Methoden: Basierend auf einer systematischen Literaturrecherche werden randomisierte kontrollierte Studien zur Wirksamkeit der HPV-Impfungen für die Prävention von Zervixkarzinomen bzw. deren Vorstufen, den zervikalen intraepithelialen Neoplasien, identifiziert. Gesundheitsökonomische Modellierungen werden zur Beantwortung der ökonomischen Fragestellungen herangezogen. Die Beurteilung der Qualität der medizinischen und ökonomischen Studien erfolgt mittels anerkannter Standards zur systematischen Bewertung wissenschaftlicher Studien Ergebnisse: Bei zu Studienbeginn HPV 16/18 negativen Frauen, die alle Impfdosen erhalten haben, liegt die Wirksamkeit der Impfungen gegen HPV 16/18-induzierten CIN 2 oder höher bei 98% bis 100%. Nebenwirkungen der Impfung sind vor allem mit der Injektion assoziierte Beschwerden (Rötungen, Schwellungen, Schmerzen). Es gibt keine signifikanten Unterschiede für schwerwiegende unerwünschte Ereignisse zwischen Impf- und Placebogruppe. Die Ergebnisse der Basisfallanalysen der gesundheitsökonomischen Modellierungen reichen bei ausschließlicher Berücksichtigung direkter Kostenkomponenten von ca. 3.000 Euro bis ca. 40.000 Euro pro QALY (QALY = Qualitätskorrigiertes Lebensjahr), bzw. von ca. 9.000 Euro bis ca. 65.000 Euro pro LYG (LYG = Gewonnenes Lebensjahr). Diskussion: Nach den Ergebnissen der eingeschlossenen Studien sind die verfügbaren HPV-Impfstoffe wirksam zur Prävention gegen durch HPV 16/18 verursachte prämaligne Läsionen der Zervix. Unklar ist derzeit noch die Dauer des Impfschutzes. Hinsichtlich der Nebenwirkungen ist die Impfung als sicher einzustufen. Allerdings ist die Fallzahl der Studien nicht ausreichend groß, um das Auftreten sehr seltener Nebenwirkungen zuverlässig zu bestimmen. Inwieweit die HPV-Impfung zur Reduktion der Inzidenz und Mortalität des Zervixkarzinoms in Deutschland führen wird, hängt nicht allein von der klinischen Wirksamkeit der Impfstoffe ab, sondern wird von einer Reihe weiterer Faktoren wie der Impfquote oder den Auswirkungen der Impfungen auf die Teilnahmerate an den bestehenden Screeningprogrammen determiniert. Infolge der Heterogenität der methodischen Rahmenbedingungen und Inputparameter variieren die Ergebnisse der gesundheitsökonomischen Modellierungen erheblich. Fast alle Modellanalysen lassen jedoch den Schluss zu, dass die Einführung einer Impfung mit lebenslanger Schutzdauer bei Fortführung der derzeitigen Screeningpraxis als kosteneffektiv zu bewerten ist. Eine Gegenüberstellung der beiden verschiedenen Impfstoffe ergab, dass die Modellierung der tetravalenten Impfung bei der Berücksichtigung von QALY als Ergebnisparameter in der Regel mit einem niedrigeren (besseren) Kosten-Effektivitäts-Verhältnis einhergeht als die Modellierung der bivalenten Impfung, da auch Genitalwarzen berücksichtigt werden. In Sensitivitätsanalysen stellten sich sowohl die Schutzdauer der Impfung als auch die Höhe der Diskontierungsrate als wesentliche Einflussparameter der Kosten-Effektivität heraus. Schlussfolgerung: Die Einführung der HPV-Impfung kann zu einem verringerten Auftreten von Zervixkarzinomen bei geimpften Frauen führen. Jedoch sollten die Impfprogramme von weiteren Evaluationen begleitet werden, um die langfristige Wirksamkeit und Sicherheit beurteilen sowie die Umsetzung der Impfprogramme optimieren zu können. Von zentraler Bedeutung sind hohe Teilnahmeraten sowohl an den Impfprogrammen als auch - auch bei geimpften Frauen - an den Früherkennungsuntersuchungen. Da die Kosten-Effektivität entscheidend von der Schutzdauer, die bislang ungewiss ist, beeinflusst wird, ist eine abschließende Beurteilung der Kosten-Effektivität der HPV-Impfung nicht möglich. Eine langfristige Schutzdauer ist eine bedeutende Vorraussetzung für die Kosten-Effektivität der Impfung. Der Abschluss einer Risk-Sharing-Vereinbarung zwischen Kostenträgern und Herstellerfirmen stellt eine Option dar, um die Auswirkungen der Unsicherheit der Schutzdauer auf die Kosten-Effektivität zu begrenzen.

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Background: Langerhans cell histiocytosis is a rare proliferative histiocytic disease of unknown etiology. Histologically, it is characterized by granuloma-like proliferation of Langerhans-type dendritic cells derived from bone marrow. Many investigators have suggested the possible role of viruses such as Epstein-Barr virus, human herpesvirus-6 (HHV-6), herpes simplex virus (HSV) types 1 and 2, and Cytomegalovirus in the pathogenesis of Langerhans cell histiocytosis. Objectives: In this study, we have investigated the presence of Cytomegalovirus in Langerhans cell histiocytosis in Iranian children. Patients and Methods: In this retrospective study, we have investigated the presence of Cytomegalovirus DNA expression, using paraffin-embedded tissue samples of 30 patients with Langerhans cell histiocytosis and 30 age and site-matched controls by qualitative Polymerase Chain Reaction (PCR) method. Results: No significant difference in prevalence of Cytomegalovirus presence between patients and controls was found. Cytomegalovirus was found by qualitative PCR in only 2 (6.66%) out of 30 patients and in 1 (3.3%) of 30 control samples with a P value of 1 (1.00 > 0.05) using chi-square test with OR: 2.07; 95% CI of OR: 0.18 - 24.15. Conclusions: Our findings do not support the hypothesis of a possible role for Cytomegalovirus in the pathogenesis of Langerhans cell histiocytosis.

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Sarcocystis species are worldwide spread cyst-forming protozoa that can infect wild boar but little is known about the prevalence of these parasites. In this study we assessed the prevalence of Sarcocystis spp. infections in wild boars from northeastern Portugal, for which novel PCR testing assays targeting Sarcocystis genus, S. miescheriana and S. suihominis were implemented, and risk factors potentially associated with these infections were evaluated. Samples from muscle tissue, namely diaphragm (n = 102), oesophagus (n = 96) and heart (n = 101), were collected from a total of 103 wild boar hunted between October 2011 and February 2012. Diaphragm muscle was used for the PCR detection of Sarcocystis nucleic acids since a higher proportion of samples showed the presence of cysts during histological examination. PCR assay targeting Sarcocystis genus yielded a 73.8% infection rate, which indicate a high level of exposure to these protozoan parasites among wild boars. These samples showed to be positive with the S. miescheriana-specific PCR assay and no sample was positive with the S. suihominis-specific assay, suggesting that a single species infecting wild boar is circulating in Portugal. These results were confirmed by the partial sequencing of the 18S rRNA gene amplified from selected samples from different geographic regions. Adults, young adults and female wild boars were found to be more likely infected. Hunters have an important role in the life cycle of S. miescheriana since potentially infected viscera and carcasses can be left behind promoting the protozoan dissemination to the scavenging final hosts. If hunting dogs bite and ingest infected meat they can perpetuate the life cycle of Sarcocystis spp. spreading oocysts or sporocysts in the environment.

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Separately, actinic keratosis (AK) and cutaneous squamous cell carcinoma (SCC) have been associated with cutaneous human papillomavirus (HPV) infections. To further explore the association between HPV infection and SCC development, we determined markers of cutaneous HPV infection within a single population in persons with precursor lesions (AK), cancerous lesions (SCC), and without. Serum and plucked eyebrow hairs were collected from 57 tumor-free controls, 126 AK, and 64 SCC cases. Presence of HPV L1 and E6 seroreactivity and viral DNA were determined for HPV types 5, 8, 15, 16, 20, 24, and 38. Significant positive associations with increasing severity of the lesions (controls, AK, and SCC, respectively) were observed for overall HPV L1 seropositivity (13%, 26%, and 37%) and for HPV8 (4%, 17%, and 30%). In parallel, the proportion of L1 seropositive individuals against multiple HPV types increased from 14% to 39% and 45%. The overall E6 seroreactivity, however, tended to decline with AK and SCC, especially for HPV8 (21%, 11%, and 2%). HPV DNA positivity was most prevalent in the AK cases (54%) compared with the SCC cases (44%) and the tumor-free controls (40%). Among all participants, there was a positive trend between overall HPV DNA positivity and L1 seropositivity, but not E6 seropositivity. Taken together, our data suggest that cutaneous HPV infections accompanied by detectable HPV DNA in eyebrow hairs and HPV L1 seropositivity, but not E6 seropositivity, are associated with an increased risk of AK and SCC.

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Urinary tract infections (UTIs) are among the most common bacterial infections in humans. Murine models of human UTI are vital experimental tools that have helped to elucidate UTI pathogenesis and advance knowledge of potential treatment and infection prevention strategies. Fundamentally, several variables are inherent in different murine models, and understanding the limitations of these variables provides an opportunity to understand how models may be best applied to research aimed at mimicking human disease. In this review, we discuss variables inherent in murine UTI model studies and how these affect model usage, data analysis and data interpretation. We examine recent studies that have elucidated UTI host–pathogen interactions from the perspective of gene expression, and review new studies of biofilm and UTI preventative approaches. We also consider potential standards for variables inherent in murine UTI models and discuss how these might expand the utility of models for mimicking human disease and uncovering new aspects of pathogenesis

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Japanese encephalitis virus (JEV) is a single stranded RNA virus that infects the central nervous system leading to acute encephalitis in children. Alterations in brain endothelial cells have been shown to precede the entry of this flavivirus into the brain, but infection of endothelial cells by JEV and their consequences are still unclear. Productive JEV infection was established in human endothelial cells leading to IFN-beta and TNF-alpha production. The MHC genes for HLA-A, -B, -C and HLA-E antigens were upregulated in human brain microvascular endothelial cells, the endothelial-like cell line, ECV 304 and human foreskin fibroblasts upon JEV infection. We also report the release/shedding of soluble HLA-E (sHLA-E) from JEV infected human endothelial cells for the first time. This shedding of sHLA-E was blocked by an inhibitor of matrix metalloproteinases (MMP). In addition, MMP-9, a known mediator of HLA solubilisation was upregulated by JEV. In contrast, human fibroblasts showed only upregulation of cell-surface HLA-E. Addition of UV inactivated JEV-infected cell culture supernatants stimulated shedding of sHLA-E from uninfected ECV cells indicating a role for soluble factors/cytokines in the shedding process. Antibody mediated neutralization of TNF-alpha as well as IFNAR receptor together not only resulted in inhibition of sHLA-E shedding from uninfected cells, it also inhibited HLA-E and MMP-9 gene expression in JEV-infected cells. Shedding of sHLA-E was also observed with purified TNF-alpha and IFN-beta as well as the dsRNA analog, poly (I:C). Both IFN-beta and TNF-alpha further potentiated the shedding when added together. The role of soluble MHC antigens in JEV infection is hitherto unknown and therefore needs further investigation.

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[en]Human papillomavirus (HPV) belongs to the Papillomaviridae virus family and it is one of the most common sexual transmission infections. HPV genome is composed of eight genes, including two early genes and six late genes. Among these late genes, E6 and E7 code for proteins that trigger cell-cycle re-entry in infected cells, which can lead to cervical cancer development. The IARC (International Agency for Research Cancer) proposed a guideline based on Hill’s criteria to determine whether the relation between HPV infection and cervical cancer is causal or not. Epidemiological studies have demonstrated that HPV infection is a necessary but non-sufficient cause for cervical cancer. Furthermore, HPV infection is considered the first necessary cause described of a human cancer, being HPV16 and 18 carcinogenic to humans and the most studied types. Cervical cancer is the second leading cause of cancer death among women worldwide. Different screening programs are carried out with the aim of preventing cervical cancer; such as cytologies and HPV tests. There are two main methods which are equally usable to detect HPV: the real-time PCR assays and the array assays. Regarding the molecular mechanisms of HPV mediated malignancies, E2, E6 and E7 proteins of HPV16 lead to immune response evasion, inducing IL-10 and TGF-β1 gene expression. Besides, E6 and E7 proteins allow cell-cycle reentry, phosphorylating RB and ubiquitinating p53 respectively. HPV genome integration in host genome leads to the alteration of host and viral genes expression, including oncogenes and tumor suppressor genes. However, the differences of E6 and E7 oncoproteins in different HPV types is poorly known due to the fact that almost the most studied HPV type has been HPV16.