886 resultados para Overturning of control blocks
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A forty-year-old man underwent an allogeneic BMT from his HLA identical sister. GvHD prophylaxis was done with cyclosporine (CyA), methotrexate and prednisone (PDN). On day +90 extensive GvHD was noted and higher doses of immunosuppressive drugs alternating CyA with PDN were initiated. Patient's follow-up was complicated by intermittent episodes of leukopenia and monthly episodes of sinusitis or pneumonia. One year after BMT, the patient developed hoarseness and nasal voice. No etiologic agent could be identified on a biopsy sample of the vocal chord. Upon tapering the doses of immunosuppressive drugs, the patient had worsening of chronic GvHD and was reintroduced on high doses of cyclosporine alternating with prednisone on day +550. Three months later, GvHD remained out of control and the patient was started on azathioprine. On day +700, hoarseness and nasal voice recurred. Another biopsy of the left vocal chord failed to demonstrate infection. Episodes of sinusitis became more frequent and azathioprine was withheld 3 months after it was started. One month later, the patient had bloody nasal discharge and surgical drainage of maxillary sinuses was performed. Histopathology showed hyphae and cultures grew Scedosporium apiospermum. ltraconazole 800 mg/day was initiated. The patient developed progressive respiratory failure and died 15 days later.
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The shifted Legendre orthogonal polynomials are used for the numerical solution of a new formulation for the multi-dimensional fractional optimal control problem (M-DFOCP) with a quadratic performance index. The fractional derivatives are described in the Caputo sense. The Lagrange multiplier method for the constrained extremum and the operational matrix of fractional integrals are used together with the help of the properties of the shifted Legendre orthonormal polynomials. The method reduces the M-DFOCP to a simpler problem that consists of solving a system of algebraic equations. For confirming the efficiency and accuracy of the proposed scheme, some test problems are implemented with their approximate solutions.
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This study was undertaken in the municipality of Bananal, São Paulo, an endemic area for schistosomiasis with a prevalence under 10% and low parasite load among infected individuals. Our objective was to identify the clinical forms of schistosomiasis among 109 patients in whom the disease had been diagnosed through direct fecal analysis and who had been medicated with oxamniquine at the time of the Plan for the Intensification of Schistosomiasis Control Actions (1998-2000). These patients were submitted to an abdominal ultrasonography and fecal analysis by Kato-Katz method, four years, on average, after the end of the Plan. Five patients, whose abdominal ultrasound images were compatible with either peripheral or central periportal fibrosis and portal hypertension, were identified. None of the 109 patients presented Schistosoma mansoni eggs at fecal analysis. Ultrasonography is a sensitive, noninvasive diagnostic method that allows a better identification of the extent of liver involvement in schistosomiasis cases.
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Despite the importance of understanding the epidemiology of agents responsible for infectious diarrhea in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) population, the number of articles about this subject is relatively few. The current article summarizes published data on bacterial, fungal, viral and parasitic enteropathogens in the HIV/AIDS seropositive subjects in different countries, regions and localities. In general, there is a great difference in the frequencies of etiological agents due to factors which include immune status, geographical location, climate and socioeconomic conditions. It is important to stress that a great prevalence of infection by emergent agents has been reported in the more advanced stages of AIDS. Therefore, to establish specific treatment depends directly on knowledge of these agents and risk factors associated to their distribution. Moreover, the colonization by potential pathogenic agents verified in these individuals is high thus implicating that they act as carriers. Finally, public health measures of control and prevention must take into consideration the regional previously identified enteropathogens, especially in areas where HIV prevalence is high.
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The effect of sub-lethal feeding of bait formulations containing molluscicidal component of Ferula asafoetida (ferulic acid, umbelliferone), Syzygium aromaticum (eugenol) and Carum carvi (limonene) on biochemical changes in the ovotestis of snail Lymnaea acuminata were studied. Bait formulations feeding to L. acuminata were studied in clear glass aquaria having diameter of 30 cm. Baits were prepared from different binary combinations of attractant amino acid (valine, aspartic acid, lysine and alanine 10 mM) in 100 mL of 2% agar solution + sub-lethal (20% and 60% of 24h LC50) doses of different molluscicides (ferulic acid, umbelliferone, eugenol and limonene). These baits caused maximum significant reduction in free amino acid, protein, DNA, RNA levels i.e. 41.37, 23.56, 48.36 and 14.29% of control in the ovotestis of the snail, respectively. Discontinuation of feeding after treatment of 60% of 96h LC50 of molluscicide containing bait for next 72h caused a significant recovery in free amino acid, protein, DNA and RNA levels in the ovotestis of L. acuminata.
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Irrigation schemes and dams have posed a great concern on public health systems of several countries, mainly in the tropics. The focus of the present review is to elucidate the different ways how these human interventions may have an effect on population dynamics of anopheline mosquitoes and hence, how local malaria transmission patterns may be changed. We discuss different studies within the three main tropical and sub-tropical regions (namely Africa, Asia and the Pacific and the Americas). Factors such as pre-human impact malaria epidemiological patterns, control measures, demographic movements, human behaviour and local Anopheles bionomics would determine if the implementation of an irrigation scheme or a dam will have negative effects on human health. Some examples of successful implementation of control measures in such settings are presented. The use of Geographic Information System as a powerful tool to assist on the study and control of malaria in these scenarios is also highlighted.
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The diagnosis of asymptomatic infection with Leishmania (Leishmania) chagasi has become more important over recent years. Expansion of visceral leishmaniasis might be associated with other routes of transmission such as transfusion, congenital or even vector transmission, and subjects with asymptomatic infection are potential reservoirs. Moreover, the identification of infection may contribute to the management of patients with immunosuppressive conditions (HIV, transplants, use of immunomodulators) and to the assessment of the effectiveness of control measures. In this study, 149 subjects living in a visceral leishmaniasis endemic area were evaluated clinically and submitted to genus-specific polymerase chain reaction (PCR), serological testing, and the Montenegro skin test. Forty-nine (32.9%) of the subjects had a positive PCR result and none of them developed the disease within a follow-up period of three years. No association was observed between the results of PCR, serological and skin tests. A positive PCR result in subjects from the endemic area did not indicate a risk of progression to visceral leishmaniasis and was not associated with a positive result in the serological tests.
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Leishmaniasis remains a major public health problem worldwide and is classified as Category I by the TDR/WHO, mainly due to the absence of control. Many experimental models like rodents, dogs and monkeys have been developed, each with specific features, in order to characterize the immune response to Leishmania species, but none reproduces the pathology observed in human disease. Conflicting data may arise in part because different parasite strains or species are being examined, different tissue targets (mice footpad, ear, or base of tail) are being infected, and different numbers (“low” 1×102 and “high” 1×106) of metacyclic promastigotes have been inoculated. Recently, new approaches have been proposed to provide more meaningful data regarding the host response and pathogenesis that parallels human disease. The use of sand fly saliva and low numbers of parasites in experimental infections has led to mimic natural transmission and find new molecules and immune mechanisms which should be considered when designing vaccines and control strategies. Moreover, the use of wild rodents as experimental models has been proposed as a good alternative for studying the host-pathogen relationships and for testing candidate vaccines. To date, using natural reservoirs to study Leishmania infection has been challenging because immunologic reagents for use in wild rodents are lacking. This review discusses the principal immunological findings against Leishmania infection in different animal models highlighting the importance of using experimental conditions similar to natural transmission and reservoir species as experimental models to study the immunopathology of the disease.
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Thesis submitted to the Instituto Superior de Estatística e Gestão de Informação da Universidade Nova de Lisboa in partial fulfillment of the requirements for the Degree of Doctor of Philosophy in Information Management – Geographic Information Systems
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Rett syndrome is a neurodevelopmental disorder caused by mutations in the MECP2 gene. We investigated the genetic basis of disease in a female patient with a Rett-like clinical. Karyotype analysis revealed a pericentric inversion in the X chromosome -46,X,inv(X)(p22.1q28), with breakpoints in the cytobands where the MECP2 and CDKL5 genes are located. FISH analysis revealed that the MECP2 gene is not dislocated by the inversion. However, and in spite of a balanced pattern of X inactivation, this patient displayed hypomethylation and an overexpression of the MECP2 gene at the mRNA level in the lymphocytes (mean fold change: 2.55±0.38) in comparison to a group of control individuals; the expression of the CDKL5 gene was similar to that of controls (mean fold change: 0.98±0.10). No gains or losses were detected in the breakpoint regions encompassing known or suspected transcription regulatory elements. We propose that the de-regulation of MECP2 expression in this patient may be due to alterations in long-range genomic interactions caused by the inversion and hypothesize that this type of epigenetic de-regulation of the MECP2 may be present in other RTT-like patients.
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Finance from the NOVA – School of Business and Economics
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The crisis has drawn attention to the fact that not only emerging powers but other regions of the world as well may be offering different development models and may constitute into alternative, in some dimensions more positive agents, in the conduct of the present stage of globalisation. Notwithstanding, the traditional western powers have not lost a large amount of control of the world economy. And the crisis proceeds, reallocating world power as in a Hobbesian anarchy. It is difficult to foresee smooth developments in the near future. On the contrary, multilateralism seems to be losing ground to unilateral action or bilateral arrangements. More or less disguised currency wars may lead to serious disequilibria, and turf wars may become more frequent, with motives ranging from securing captive markets to control of specific commodities and energy goods, or targeted regulatory frameworks. As economic policy becomes even more involved with defence and security affairs, the feedbacks from each side to the other seem likely to keep dissent and animosity high, rather than contributing to peaceful and constructive approaches. A more trouble-prone world may be easily expected.
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Cats are the definitive hosts of Toxoplasma gondii. Infected cats excrete oocysts in their feces, infecting humans and other animals. The objective of the present study was to determine the presence of anti-Toxoplasma antibodies in cat owners and their pets, and determine if there was a relationship between Toxoplasma infection and humans who live with infected cats. IgG anti-Toxoplasma antibodies in sera of 59 cat owners were determined by enzyme-linked immunosorbent assay (ELISA), in 24 sera from their cats, IgG, IgM, and IgA antibodies were found using Burney's ELISA. Thirty-eight (64%) of 59 cat owners were positive to IgG anti-Toxoplasma. Seropositivity for cats was 70.8% IgG, 8.3% IgM, and 62.5% IgA. Cohabitation with cats infected by T. gondii, feeding with leftovers or raw viscera, and lack of control over how their feces were handled are risk factors conducive for humans to become infected by T. gondii.
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The proliferation of Aedes aegypti, a species of mosquito that is the vector of the dengue pathogen, is being augmented by the population's lack of care in allowing the formation of larval habitats. One form of controlling dengue is the distribution of information on the mosquito to improve awareness and to provide the means necessary for the elimination of its reproductive habitats. To evaluate a teaching method concerning the vector and dengue, students from the 5th and 6th years of primary education were compared before and after didactic intervention with a group of control students. The students who received intervention were more successful in identifying the stages of the cycle, biological and morphological characteristics of the adult insect and the importance of the mosquito in health issues. The didactic intervention was successful in developing knowledge leading to increased awareness of the importance of preventative measures that should be taken against the vector and the disease.
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RESUMO: A Malária é causada por parasitas do género Plasmodium, sendo a doença parasitária mais fatal para o ser humano. Apesar de, durante o século passado, o desenvolvimento económico e a implementação de diversas medidas de controlo, tenham permitido erradicar a doença em muitos países, a Malária continua a ser um problema de saúde grave, em particular nos países em desenvolvimento. A Malária é transmitida através da picada de uma fêmea de mosquito do género Anopheles. Durante a picada, os esporozoítos são injetados na pele do hospedeiro, seguindo-se a fase hepática e obrigatória do ciclo de vida. No fígado, os esporozoítos infetam os hepatócitos onde se replicam, dentro de um vacúolo parasitário (VP) e de uma forma imunitária silenciosa, em centenas de merozoitos. Estas novas formas do parasita são as responsáveis por infetar os eritrócitos, iniciando a fase sanguínea da doença, onde se os primeiros sintomas se manifestam, tais como a característica febre cíclica. A fase hepática da doença é a menos estudada e compreendida. Mais ainda, as interações entre o VP e os organelos da células hospedeira estão ainda pouco caracterizados. Assim, neste estudo, as interações entre os organelos endocíticos e autofágicos da célula hospedeira e o VP foram dissecados, observando-se que os anfisomas, que são organelos resultantes da intersecção do dois processos de tráfego intracelular, interagem com o parasita. Descobrimos que a autofagia tem também uma importante função imunitária durante a fase hepática inicial, ao passo, que durante o desenvolvimento do parasita, já numa fase mais tardia, o parasita depende da interação com os endossomas tardios e anfisomas para crescer. Vesiculas de BSA, EGF e LC3, foram, também, observadas dentro do VP, sugerindo que os parasitas são capazes de internalizar material endocítico e autofágico do hospedeiro. Mais ainda, mostramos que esta interação depende da cinase PIKfyve, responsável pela conversão do fosfoinositidio-3-fosfato no fosfoinositidio-3,5-bifosfato, uma vez que inibindo esta cinase o parasita não é capaz de crescer normalmente. Finalmente, mostramos que a proteína TRPML1, uma proteína efetora do fosfoinositidio-3,5-bifosfato, e envolvida no processo de fusão das membranas dos organelos endocíticos e autofágicos, também é necessária para o crescimento do parasita. Desta forma, o nosso estudo sugere que a membrana do VP funde com vesiculas endocíticas e autofágicas tardias, de uma forma dependente do fositidio-3,5-bifosfato e do seu effetor TRPML1, permitindo a troca de material com a célula hospedeira. Concluindo, os nossos resultados evidenciam que o processo autofágico que ocorre na célula hospedeira tem um papel duplo durante a fase hepática da malaria. Enquanto numa fase inicial os hepatócitos usam o processo autofágico como forma de defesa contra o parasita, já durante a fase de replicação o VP funde com vesiculas autofágicas e endocíticas de forma a obter os nutrientes necessários ao seu desenvolvimento.--------- ABSTRACT: Malaria, which is caused by parasites of the genus Plasmodium, is the most deadly parasitic infection in humans. Although economic development and the implementation of control measures during the last century have erradicated the disease from many areas of the world, it remains a serious human health issue, particularly in developing countries. Malaria is transmitted by female mosquitoes of the genus Anopheles. During the mosquito blood meal, Plasmodium spp. sporozoites are injected into the skin dermis of the vertebrate host, followed by an obligatory liver stage. Upon entering the liver, Plasmodium parasites infect hepatocytes and silently replicate inside a host cell-derived parasitophorous vacuole (PV) into thousands of merozoites. These new parasite forms can infect red blood cells initiating the the blood stage of the disease which shows the characteristic febrile malaria episodes. The liver stage is the least characterized step of the malaria infection. Moreover, the interactions between the Plasmodium spp. PV and the host cell trafficking pathways are poorly understood. We dissected the interaction between Plasmodium parasites and the host cell endocytic and autophagic pathways and we found that both pathways intersect and interconnect in the close vicinity of the parasite PV, where amphisomes are formed and accumulate. Interestingly, we observed a clearance function for autophagy in hepatocytes infected with Plasmodium berghei parasites at early infection times, whereas during late liver stage development late endosomes and amphisomes are required for parasite growth. Moreover, we found the presence of internalized BSA, EGF and LC3 inside parasite vacuoles, suggesting that the parasites uptake endocytic and autophagic cargo. Furthermore, we showed that the interaction between the PV and host traffic pathways is dependent on the kinase PIKfyve, which converts the phosphoinositide PI(3)P into PI(3,5)P2, since PIKfyve inhibition caused a reduction in parasite growth. Finally, we showed that the PI(3,5)P2 effector protein TRPML1, which is involved in late endocytic and autophagic membrane fusion, is also required for parasite development. Thus, our studies suggest that the parasite parasitophorous vacuole membrane (PVM) is able to fuse with late endocytic and autophagic vesicles in a PI(3,5)P2- and TRPML1-dependent manner, allowing the exchange of material between the host cell and the parasites, necessary for the rapid development of the latter that is seen during the liver stage of infection. In conclusion, we present evidence supporting a specific and essential dual role of host autophagy during the course of Plasmodium liver infection. Whereas in the initial hours of infection the host cell uses autophagy as a cell survival mechanism to fight the infection, during the replicative phase the PV fuses with host autophagic and endocytic vesicles to obtain nutrients required for parasite growth.