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Artrite-encefalite dos caprinos - aspectos clínicos e epidemiológicos / Caprine arthritis encephalitis - Clinical and epidemiological featuresMaria do Carmo Custodio de Souza Hunold Lara 10 April 2002 (has links)
Estudou-se a freqüência da ocorrência de anticorpos antivírus da Artrite-encefalite dos Caprinos, em caprinos de 14 plantéis localizados no Estado de São Paulo, por um período de 2 anos, utilizando-se a técnica de imunodifusão em gel de ágar. A prevalência obtida foi de 26,3%, sendo significativamente maior nos caprinos mantidos em regime intensivo (31,8% - 733/2303) de criação do que no sistema semi-extensivo (13,1% - 128- 977). A infecção pelo vírus da Artrite-encefalite dos Caprinos aumentou gradativa e significativamente após os 6 meses de idade, havendo predominância da infecção nos caprinos mais velhos. Não se detectou influência de fatores sexuais sobre a prevalência da enfermidade determinada em caprinos do sexo feminino (27,9% - 663/2375) e masculino (32,3% - 94/291). A prevalência da doença foi significativamente maior nos caprinos das raças Anglo Nubiana (63,8% - 88/138) e Toggenbourg (56,0% - 28/50) do que nas demais raças estudadas: Saanen (27,4% - 673/2458), Alpina (11,9% - 59/497), Bôer (5,9% - 2/34) e caprinos mestiços (10,7% - 11/103). Paralelamente realizou-se estudo clínico dos animais infectados pelo vírus da Artrite-encefalite dos Caprinos, quando pudemos demonstrar que 17,1% (64/374) dos caprinos sororeagentes apresentavam a forma clínica articular da enfermidade e que 6,6% (17/249) das cabras sororeagentes apresentavam a forma mamária. A possibilidade de transmissão vertical transplacentária foi menor do que 3,8%. Verificou-se ser pequena a possibilidade dos cabritos se infectarem pelo colostro de cabras sororeagentes positivas, mas podem se infectar pelo leite oriundos dessas cabras infectadas (18,8% - 3/16). O tempo de duração dos anticorpos séricos adquiridos passivamente pelo colostro variou de 60 a 120 dias. Demonstrou-se, indiretamente, a presença e a viabilidade do vírus no sangue circulante, colostro e leite de caprinos infectados, bem como a possibilidadede infectar animais susceptíveis por inoculação, sendo o período de incubação de 45 a 60 dias. Não se demonstrou diferenças significativas dos teores séricos de proteína total, gamaglobulina e da atividade enzimática da glutamiltransferase - γGT em cabritos que receberam colostro de cabras infectadas ou não infectadas pelo mencionado vírus. / The frequency of occurrence of antibodies anti-caprine arthritis-encephalitis virus was studied in 14 herds in the State of São Paulo, during 2 years, using agar gel immunodiffusion. Prevalence was equal to 26.3%, and was significantly higher in animals kept under an intensive management scheme (31.8% - 733/2303), than in animals kept under a semi-extensive one (13.1% - 128- 977). Infection by the caprine arthritis-encephalitis virus increased gradual and significantly after 6 months of age. Infection was predominant in older animals. There was no gender influence on the prevalence of the disease, both in females (27.9% - 663/2375) and males (32.3% - 94/291). In relation to breed, prevalence of the disease was significantly higher in Anglo-Nubian (63.8% - 88/138) and Toggenbourg animals (56.0% - 28/50), than in the rest of the breeds studied: Saanen (27.4% - 673/2458), Alpine (11.9% - 59/497), Boer (5.9% - 2/34) and mixed breed animals (10.7% - 11/103). A clinical study of the animals infected by caprine arthritis-encephalitis virus was also performed. It was observed that 17.1% (64/374) of seroreagents presented the articular form of the disease and that 6.6% (17/249) of the seroreagent females presented the mammary form of the disease. The possibility of vertical, transplacentary transmission was lower than 3.8%. It was observed that the probability of infection of kids by colostrum of infected females was low (18.8% - 3/16). Antibodies passively acquired by colostrum ingestion lasted from 60 to 120 days. The presence and viability of the virus circulating in blood, colostrum and milk of infected animals, as well as the possibility of infection of susceptible animals by inoculation was indirectly demonstrated. Incubation period ranged from 45 to 60 days. There was no significant difference in serum levels of total protein and gammaglobulin, and in enzymatic activity of glutamiltransferase - γGT in kids that received colostrum from infected and non-infected females.
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Influência do vírus da artrite encefalite caprina no imunograma sanguíneo e lácteo de cabras naturalmente infectadas / Influence of caprine arthritis encephalitis virus on blood and milk immunogram of naturally infected goatsBruna Parapinski dos Santos 31 July 2012 (has links)
A Artrite Encefalite Caprina (AEC) é uma lentivirose multisistêmica que tem a glândula mamária caprina como um dos alvos lesionais da doença. Pode causar uma manifestação mamária específica, chamada de mastite endurativa, além da mama representar uma importante via de eliminação do vírus, mesmo em animais que não apresentam a forma clínica. Considerando-se a possibilidade desta virose, cuja célula alvo predominante é o monócito, levar a alterações imunológicas que influenciem a susceptibilidade do animal a outras doenças, objetivou-se avaliar essa interação do vírus e da imunidade do hospedeiro por meio de fenotipagem, fagocitose e produção de Espécies reativas de oxigênio (ERO) e dos mecanismos de morte das células sanguíneas e lácteas de cabras naturalmente infectadas. Para isso 200 cabras foram triadas e, destas selecionadas oito fêmeas não sororreagentes e dez sororreagentes na pesquisa de anticorpos séricos para AEC, dentro dos padrões hematológicos da espécie e com dois exames bacteriológicos do leite negativos. O leite e o sangue colhido destes animais foram submetidos às seguintes provas: fenotipagem dos leucócitos CD4+, CD8+, CD14+, PG68A+ e CD45+, fagocitose de Staphylococcus aureus e de Escherichia coli por células CD14+ e PG68A+, produção de ERO e marcação com Anexina-V e Iodeto de Propídeo (PI) por granulócitos e células mononucleares. A infecção pelo VAEC pode ser associada a um aumento de células CD14+ no leite, mas não no sangue. Os outros perfis celulares não sofreram alterações. Quanto a função fagocítica, o vírus reduziu a porcentagem de fagocitose de Staphylococcus aureus por granulócitos PG68A+ do leite. Esta alteração não ocorreu na fagocitose de Escherichia coli e na produção de ERO dessas células, nem na fagocitose e produção de ERO pelas células CD14+ ressaltando que nesses processos a espécie bacteriana pode sofrer interações com o vírus ou mesmo com a resposta imune do organismo infectado. O VAEC não influenciou significativamente os mecanismos de morte ora investigados, mas a tendência dos resultados sugere que possa haver indução de morte por apoptose e/ou por necrose nos granulócitos do sangue e influenciar no processo de necrose destas células no leite, sem alterar esses processos nas células mononucleares. Ressalta-se a importância da interação monócito-neutrófilo na glândula mamária, principalmente nos animais sororreagentes para AEC, mesmo na ausência de mastite bacteriana. / The caprine arthritis encephalitis (CAE) is a multisystem lentivirose that have the goat mammary gland as one target of the lesional disease. May cause a mammary specific expression, called indurative mastitis, beyond these organ represent a major route of virus elimination, even in animals that do not exhibit this clinical manifestation. Considering the possibility of this virus, whose target cell are predominantly monocyte, lead to immunological changes that influence the animal\'s susceptibility to other diseases, this study aimed to evaluate the interaction of virus and host immunity by phenotyping, phagocytosis and production of reactive oxygen species (ROS) and the mechanisms of cell death, in blood and milk of goats naturally infected. For that, 200 goats were screened and was selected eight females non sero-reagents and ten seroreagents for serum antibodies against CAE, with the haematological analises within the species standards and two negative bacteriological tests of milk. Milk and blood from these animals underwent the following tests: phenotyping of leukocytes CD4+, CD8+, CD14+, PG68A+ and CD45+, phagocytosis of Staphylococcus aureus and Escherichia coli ROS production by CD14+ and PG68A+ cells, and labeling with Annexin-V and propidium iodide (PI) for granulocytes and mononuclear cells. CAEV infection may be associated with an increase in CD14+ cells in milk, but not in blood. The other cellular profile did not change. In the phagocytic function, the virus reduced the percentage of phagocytosis of Staphylococcus aureus by granulocytes PG68A+ milk. This change did not occur in the phagocytosis of Escherichia coli and production of ROS in these cells, nor in phagocytosis and ROS production by CD14+ cells, noting that in those cases the bacterial species may undergo interactions with the virus or even with the immune response of the infected organism. The VAEC not significantly affect the mechanism of death now investigated, but the tendency of the results suggests that can induce apoptosis and/or necrosis in the blood granulocytes and influence the process of necrosis of these cells in milk, without changing these processes mononuclear cells. We emphasize the importance of monocyte-neutrophil interaction in the mammary gland, especially in animals seropositive for CAE, even in the absence of bacterial mastitis.
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Efeito da sinvastatina na evolução clínica e na resposta imune celular Th17 na encefalite auto-imune experimental / The Effects of Simvastatin in Clinical Outcome and in the Development of Th17 Immune Response in Experimental Autoimmune EncephalomyelitisDaniel May de Oliveira 08 October 2009 (has links)
Encefalite auto-imune experimental (EAE) é o modelo animal da doença humana esclerose múltipla. Foi demonstrado que as estatinas podem ter efeitos benéficos na EAE. Diversos mecanismos de ação foram descritos para explicar esses efeitos, entre eles: estímulo a expressão de HO-1, inibição da expressão de Toll-like receptors (TLR) e inibição da produção de citocinas de padrão Th1. Estudamos o efeito de uma estatina, a sinvastatina, na evolução clínica da EAE e seus mecanismos de ação. Também avaliamos o papel do TLR4 na EAE. O tratamento com sinvastatina melhorou a evolução clínica da EAE nas doses de 1 e 5 mg/kg/dia. A análise do infiltrado celular no SNC mostrou mudança do padrão de diferenciação dos linfócitos com menor porcentagem de células produtoras de IL-17 nos grupos tratados em relação aos controles. Os animais TLR-4 -/- apresentaram melhor evolução da doença. Concluímos que o tratamento com sinvastatina melhora a evolução clínica da EAE através da inibição da produção de IL-17 e que animais TLR-4 -/- têm melhor desfecho clínico na EAE que os controles. / Experimental autoimmune encephalomyelitis (EAE) is considered the experimental model for the human multiple sclerosis disease. It has been demonstrated that statins, used as lipid-lowering agents, can have beneficial effects on EAE. Several actions have been described to explain these effects: enhancement of HO-1 expression, inhibition of Toll-like receptors expression and inhibition of Th1 cytokines. We have investigated the effect of a statin, simvastatin, on EAE clinical development and the mechanisms behind those effects. Simvastatin treatment ameliorated EAE clinical outcome at doses 1 and 5 mg/kg/day. SNC cellular infiltrates analysis showed altered pattern of differentiation with decreased percentage of IL-17-producing T lymphocytes in treated group comparing with controls. TLR4 -/- mice showed better clinical development. We concluded that simvastatin treatment ameliorates EAE clinical outcome through inhibition of IL-17 production. Mice TLR4 -/- have better EAE clinical outcome than WT controls.
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Systematic review and meta-analysis of secondary prophylaxis for prevention of HIV-related toxoplasmic encephalitis relapse using trimethoprim-sulfamethoxazoleConnolly, Mark P., Haitsma, Gertruud, Hernández, Adrián V., Vidal, José E. 20 October 2017 (has links)
A recent systematic literature and meta-analysis reported relative efficacy of trimethoprim-sulfamethoxazole (TMP-SMX) for the treatment of toxoplasmic encephalitis (TE) in HIV-infected adults. Here, we estimated relapse rates during secondary prophylaxis with TMP-SMX, and further explored differences in relapse rates prior to introduction of highly active antiretroviral therapy (HAART) and the widespread adoption of HAART. A systematic search of PubMed, Embase, and Cochrane Central Register of Controlled Trials yielded 707 studies whereby 663 were excluded after abstract screening, and 38 were excluded after full review leaving 6 studies for extraction. We performed double data extraction with a third-party adjudicator. Study designs varied with only one randomized study, four prospective cohorts and one retrospective cohort. Relapse rates were transformed using the Freeman-Tukey method and pooled using both fixed-effect and random-effects meta-analysis models. The TMP-SMX relapse rate was 16.4% (95% CI = 6.2% to 30.3%) based on random-effects models. When the disaggregated pre-HAART studies (n = 4) were included, the relapse rate was 14.9% (random effects; 95% CI = 3.7% to 31.9%). Analysis of two post-HAART studies indicated a relapse rate of 19.2% (random effects; 95% CI = 2.8% to 45.6%). Comparing the relapse rates between pre- and post-HAART studies were contrary to what might be expected based on known benefits of HAART therapy in this population. Nevertheless, cautious interpretation is necessary considering the heterogeneity of the included studies and a limited number of subjects receiving TMP-SMX reported in the post-HAART era.
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Role of the Japanese Encephalitis Virus Envelope Glycoprotein E in Viral PathogenicityGoldhardt, Joseph L. 01 December 2019 (has links)
Japanese encephalitis virus (JEV) is the causative agent of Japanese encephalitis (JE), the leading cause of vaccine-preventable neurological disease. JEV is a flavivirus that is primarily transmitted through the bite of infected mosquitoes, similar to dengue virus (DENV), St. Louis encephalitis virus (SLEV), West Nile virus (WNV), and Zika virus (ZIKV). The two viral characteristics that dictate virulence are (1) neuroinvasiveness, the ability of the virus to invade the central nervous system(CNS), and (2) neurovirulence, the capacity of the virus to kill resident cells in the CNS. The clinically proven live-attenuated JEV vaccine, SA14-14-2, lacks both pathogenic characteristics unlike its virulent parental virus, SA14. Previous work has revealed the viral E gene as the main determinant of these two pathogenic properties, though the molecular mechanisms behind their attenuation remain unclear. The E gene encodes for the viral envelope glycoprotein that is involved in viral entry into susceptible host cells. The E protein of SA14-14-2 differs from SA14 by nine amino acids. To investigate the role of these mutations in JEV virulence, we created a series of SA14E mutants using infectious cDNA technology. Here, we report the independent function of domains I (DI) and II (DII) of the viral E protein in JEV neurotropism. We reveal that an individual mutation in DI, E138K,and synergism between two mutations in DII, E244G and K279M,are independently sufficient for the attenuation of JEV neuroinvasion. Also, we report that multiple E mutations are required for full attenuation of JEV neurovirulence. Overall, our findings show the direct relationship between genetic factors and JEV neuroinvasion. These results provide a solid foundational base for the logical development of other, currently non-existing, live-attenuated neurotropic flavivirus vaccines and antivirals.
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Frühsommer-Meningoenzephalitis (FSME)-spezifische IgG Antikörper Konzentration, IgG Antikörper Avidität und FSME-spezifische T-Zell-Antwort nach primärer Vakzinierung bei Kindern mit Juveniler idiopathischer Arthritis / Tick-borne-encephalitis-(TBE)-specific IgG antibody concentrations, IgG antibody avidity and TBE-specific T-cell response after primary vaccination in children with juvenile idiopathic arthritis (JIA)Stern, Ricarda Charlotte January 2020 (has links) (PDF)
Bei Kindern mit Juveniler idiopathischer Arthritis (JIA) sind Impfungen auf Grund der immunsuppressiven Umstände durch die Erkrankung und der entsprechenden Therapie dringend empfohlen. Daher sollten JIA-Patienten, die sich längere Zeit in einem Frühsommer-Meningoenzephalitis (FSME)-Risikogebiet aufhalten oder leben, dringend eine aktive Immunisierung gegen den FSME-Virus durchführen.
In der vorliegenden Studie verglichen wir sowohl die humorale als auch die zelluläre Immunantwort auf die FSME-Impfung bei 99 gegen FSME geimpften JIA-Patienten mit 30 immunologisch gesunden, altersgleichen Kindern (HC). Dazu untersuchten wir die FSME-spezifische IgG Antikörper Konzentration und Avidität, den FSME-Neutralisations-Titer und die FSME-spezifische T-Zell-Antwort mittels IFN-γ Secretion Assay und Ermittlung der IFN-γ Konzentration im Überstand der mit FSME-Antigen stimulierten Zellkulturen.
Es zeigten sich ähnliche Ergebnisse hinsichtlich der IgG-anti-FSME-Konzentration, -Avidität und des FSME-Neutralisations-Titers. Der Erhalt von FSME-Boosterimpfungen hatte einen positiven Effekt auf die FSME-spezifische IgG Antikörper Konzentration bei den JIA-Patienten und die FSME-spezifische IgG Antikörper Avidität sowohl bei den JIA-Patienten als auch bei den HC. JIA-Patienten, die eine Therapie mit Methotrexat (MTX) während der FSME-Impfung erhielten, hatten weniger häufig einen RAI ≥ 60 %. Hinsichtlich der zellulären Immunreaktion zeigten sich ähnliche Ergebnisse zwischen den JIA-Patienten und den HC. Bei der durchflusszytometrischen Bestimmung der T-Zellen beobachteten wir in beiden Gruppen, dass die aktivierten CD4+ T-Helferzellen im Vergleich zu den aktivierten CD8+ zytotoxischen T-Zellen mehr IFN-γ nach der Stimulation mit dem FSME-Antigen produzierten. Die JIA-Patienten wiesen signifikant mehr IFN-γ produzierenden Naive-T-Zellen auf als die HC. Die humorale und zelluläre FSME-Immunreaktion schienen nicht miteinander zu korrelieren.
Ungeachtet der Tatsache, an der JIA erkrankt zu sein oder nicht, zeigten die FSME-geimpften Kinder dieser Studie auch einige Jahre nach der letzten FSME-Impfung eine ähnliche humorale und zelluläre Immunogenität gegen das FSME-Virus. Besonders wichtig ist die Gabe von FSME-Boosterimpfungen, um eine erfolgreiche Immunantwort zu erreichen und zu erhalten. Trotz des negativen Effekts der immunsuppressiven Therapie erreichten fast alle JIA-Patienten eine ausreichende humorale und zelluläre Immunogenität. Daher scheint eine erfolgreiche FSME-Immunisierung bei JIA-Patienten mit immunsuppressiver Therapie realisierbar zu sein. / In children with JIA, vaccinations are strongly recommended due to the immunosuppressive conditions caused by the disease and the corresponding therapy. Therefore, JIA patients who are remaining or living in a TBE risk area for a longer period of time are urgently ask to undergo active immunization against the TBE virus.
In the study at hand we compared both the humoral and cellular immune response to TBE vaccination in 99 JIA patients vaccinated against TBE with 30 immunologically healthy children (HC) of the same age. We investigated TBE-specific IgG antibody concentration and avidity, TBE neutralizing antibody titers and TBE-specific T-cell response by IFN-γ secretion assay and determination of the IFN-γ concentration in the supernatant of TBE antigen-stimulated cell cultures.
Similar results were obtained for TBE-specific IgG antibody concentration and avidity and TBE neutralizing antibody titers. A positive effect was noted on TBE-specific lgG antibody concentration in JIA patients as well as the TBE-specific lgG antibody avidity in both JIA patients and HC when they received a TBE booster vaccination. JIA patients who received therapy with methotrexate (MTX) during TBE vaccination were less likely to have a RAI ≥ 60 %. Regarding the cellular immune response, similar results were found between JIA patients and HC. The flow cytometric determination of T-cells we observed in both groups that activated CD4+ T-helper cells produced more IFN-γ after stimulation with the TBE antigen compared to activated CD8+ cytotoxic T-cells. The JIA patients showed significantly more IFN-γ producing naïve T cells than the HC. The humoral and cellular TBE immune response did not seem to correlate.
Regardless of whether or not the children suffered from JIA, the TBE vaccinated children in this study showed similar humoral and cellular immunogenicity against the TBE virus, even several years after the last TBE vaccination. It is thereby particularly important to perform TBE booster to achieve and maintain a successful immune response. Despite the negative effect of immunosuppressive therapy, almost all JIA patients achieved a sufficient humoral and cellular immunogenicity. Therefore, a successful TBE immunization in JIA patients with immunosuppressive therapy seems to be feasible.
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Atypical Presentation of Cerebral Palsy and Seizures: A case report on Rasmussen’s Encephalitis in an AdolescentNoordin, Naveed S, Deyo, Logan J, Ryon, Connor W, Anderson, Willie T, III 18 March 2021 (has links)
Rasmussen’s encephalitis is a rare neurological disease first described in 1958 that is characterized by medico-refractory seizures, focal unilateral cerebral inflammation, and deficits such as hemiparesis. While we still do not have a full understanding of this disease, proposed theories behind its etiology include auto-immune manifestations, immune attack by T cells, and malfunctional alterations in genetic expression. It is classically considered a rare childhood malady with a median age of onset of six years, and cases in adolescents and adults are even rarer, representing up to 10% of all cases to date. In this report, we would like to share a rare case of Rasmussen's encephalitis that occurred in an adolescent. Our 17-year-old male patient presented with signs and symptoms beginning at age 14 and was initially diagnosed with cerebral palsy only to later present with additional symptoms and characteristic EEG and MRI findings that ultimately led to a diagnosis of Rasmussen’s encephalitis. Thus, with this case report, our intent is twofold: to shed light on an atypical presentation of an already rare disease, even rarer in adolescents and adults, and to underscore the importance of keeping a broad differential when it comes to evaluating a patient with seizures.
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Analýza spontánního hlášení nežádoucích účinků po očkování proti klíšťové encefalitidě / Analysis of Spontaneous Adverse Events Reports after Tick-borne Encephalitis VaccineBrázdová, Tereza January 2021 (has links)
Analysis of Spontaneous Adverse Events Reports after Tick-Borne Encephalitis Vaccine Author: Tereza Brázdová Supervisor: PharmDr. Eva Zimčíková, Ph.D. Consultant: PharmDr. Kateřina Malá, Ph.D. Department of Social and Clinical Pharmacy, Faculty of Pharmacy in Hradec Králové, Charles University Introduction and aim: Tick-borne meningoencephalitis is one of the most frequent causes of viral meningitis in Europe. In recent years, the number of cases of this infection in the Czech Republic has begun to rise. Vaccination is the only reliable protection against infection, but it also comes with some risks. Analysis of spontaneous adverse reaction reports is a key source of information for signal detection, which is used to identify drug risks. The aim of this thesis was to analyse the spontaneous reporting of suspected adverse drug reactions (ADRs), using the data from the Central Database of ADRs provided by the State Institute for Drug Control. Methodology: Descriptive statistics were performed from reporting data in the period from June 2004 to October 2017. For example, the total number of reports, the number of ADRs and the patient characteristics were analysed. We compared the adverse reactions with the Vigibase database and evaluated the expectability of reported reactions. Results: During the...
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Kundalini, Cerebrospinal Fluid, Multidimensional HealthPortoghese, Theresia 01 April 2022 (has links)
The focus of this thesis is to explore “the inner spiritual architecture” (prāṇa, nāḍī, cakra) through the lens of the pañcamayakośa model concerning raising kuṇḍalinī. We will discuss how the components of the “spiritual architecture” are directly influenced by four select techniques (mula bandhā uḍḍīyāna bandhā, jālandhara bandhā, and mahabandā). These are known as bandhās/mudras, which are specific to The Medieval Transformation for raising kuṇḍalinī. Our focus will explore the mechanics of the bandhās and the recorded, effects.
The thesis’s secondary focus is cerebrospinal fluid (CSF). Under the traditional lens of the pañcamayakośa model, a comparison will be made between the movement of CSF and the recorded movement kuṇḍalinī when engaging mula bandhā uḍḍīyāna bandhā, jālandhara bandhā, and mahabandā. We will also consider the benefits associated with well-regulated cerebrospinal fluid (CSF) flow and compare them to the traditional benefits gained with the practice of raising kuṇḍalinī. Finally, our discussion will shift to parallels between a negative kuṇḍalinī experience and irregular CSF flow and an anecdotal account of irregular CSF flow. The conclusion will show how understanding the philosophy and techniques of raising kundalini under the lens of the pañcamayakośa model can provide unique insights regarding function, flow and manipulation of CSF health.
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Characterization of the Caprine Arthritis Encephalitis Virus (CAEV) Rev N-Terminal Elements Required for Efficient Interaction With the RREAbelson, Michelle L., Schoborg, Robert V. 01 March 2003 (has links)
The Caprine Arthritis Encephalitis Virus (CAEV) genome encodes three structural (gag, pol, and env) and three accessory (rev, tat, and vif) genes. The Rev-C protein regulates Gag, Pol and Env expression by transporting their mRNAs to the cytoplasm. Rev trans-activation requires binding of Rev to an RNA structure called the Rev Response Element (RRE-C). Previous mutational analyses have shown that two domains of Rev are required for its function. The basic domain mediates RRE binding and multimer formation, and the nuclear export signal (NES) mediates trans-activation. Preliminary experiments demonstrate that Rev-C N-terminal deletion mutants bind the RRE less avidly than does wildtype Rev. As a result, it was hypothesized that an additional domain located in the N-terminal exon of Rev-C was required for optimal RRE binding. To test this hypothesis, Rev-C alanine scanning mutants were generated and in vitro RRE binding assays were performed. Alteration of Rev-C amino acids K13, E14, N15, V19, T20, M21 and R27 dramatically decreased affinity for RRE-C. These data demonstrate that Rev-C N-terminal amino acids are required for optimal RRE-C binding and suggest that a third functional domain exists within the N-terminus of Rev-C.
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