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Real-time PCR per a la vigilància epidemiològica de la malaltia pneumocòccica invasiva (MPI) en pacients pediàtricsSelva Jové, Laura 28 June 2012 (has links)
Streptococcus pneumoniae (S. pneumoniae) és un colonitzador habitual del tracte respiratori superior dels humans. Es tracta d’un patogen comú de l’espècie humana que presenta una elevada taxa de morbiditat i mortalitat arreu del món.
El bacteri pot causar otitis mitjana, sinusitis o infeccions de tracte respiratori superior, (per contigüitat) però també pot causar malaltia invasiva, quan habita en un territori habitualment estèril, produint pneumònia, bacterièmia, septicèmies i meningitis, entre d’altres.
La malaltia pneumocòccica és un important problema de salut pública i és la principal causa individual de mortalitat infantil en el món. Segons dades de la Organització Mundial de la Salut (OMS), s’estima que a l’any 2000 es van produir 14.5 milions d’episodis greus de malaltia pneumocòccica, que va resultar en 826 000 morts en nens menors de dos anys. Un 61% d’aquestes morts es van produir a l’Àfrica subsahariana i al sud-est asiàtic. Tanmateix, en aquests països i, en especial a les zones rurals, les capacitats de diagnòstic són limitades o inexistents i la identificació de l’agent etiològic es basa en signes i símptomes clínics. És molt important aïllar l’agent etiològic causant de malaltia per tal de poder avaluar el millor tractament possible. No obstant, les tècniques actuals per al diagnòstic de la malaltia presenten una limitada sensibilitat i especificitat.
El cultiu microbiològic, com a mètode de diagnòstic clàssic, té una baixa sensibilitat per a detectar el pneumococ. L’objectiu d’aquesta tesi és avaluar el potencial de les tècniques moleculars per al diagnòstic i caracterització de la malaltia pneumocòccica i discernir si l’ús de tècniques moleculars com la reacció en cadena de la polimerasa (PCR) poden suposar un avantatge tant per la rapidesa del mètode com per la detecció del patogen present en una mostra a baixa concentració. L’aplicació d’aquest tipus de tècniques en mostres biològiques impregnades en paper de filtre (dried-spot) i conservades a temperatura ambient poden ser un excel•lent sistema per a la detecció i serotipat de S. pneumoniae en països en vies de desenvolupament on la falta de recursos econòmics esdevé una de les principals limitacions.
La capacitat del pneumococ de causar malaltia depèn de la presència d’una càpsula polisacàrida que impedeix la fagocitosi. Tot i que la presència de la càpsula és un requisit perquè produeixi malaltia, no és suficient per conferir virulència, sinó que són necessaris una varietat de factors determinants addicionals, com ara les adhesines, les proteases, les toxines, els sistemes de transport i enzims que modifiquen el medi extracel•lular. Recentment, s’ha descobert un determinant de virulència del pneumococ que és la proteïna rica en repeticions de serina, PsrP (Pneumococcal-serine rich protein). Es tracta d’una adhesina que intervé en l’adhesió del pneumococ a les cèl•lules pulmonars. PsrP és un important factor de virulència capaç de causar malaltia i un potencial candidat a una nova vacuna proteica. / Streptococcus pneumoniae (S. pneumoniae) is a common colonizer of the upper respiratory tract of humans. This is a major human pathogen and leading cause of morbidity and mortality worldwide.
The bacteria can cause otitis media, sinusitis or upper respiratory tract infections (contiguity) but can also cause invasive disease, when living in an area usually sterile, causing pneumonia, bacteraemia, sepsis and meningitis, among others.
According to the World Health Organization, in 2000, pneumococcal disease was estimated to have caused about 14.5 million severe episodes. There were approximately 826 000 deaths from pneumococcal disease in children under five years and 61% of these deaths occurred in sub-Saharan Africa and Southeast Asia. However, in these countries, especially in rural areas, diagnostic capabilities are limited or nonexistent and agent identification is based on clinical signs and symptoms. It is very important to isolate the etiologic agent of disease in order to assess the best treatment possible. However, present techniques for the diagnosis of the disease have a limited sensitivity and specificity.
Microbiological culture, considered the “gold-standard” in microbiological diagnosis has low sensitivity to detect pneumococcus. The aim of this Thesis is to evaluate the potential of molecular techniques for diagnosis and characterization of pneumococcal disease and to discern whether the use of molecular techniques such as PCR, can be an advantage both for the speed of method as for the detection of the pathogen present in a sample in low concentration. The application of these techniques in biological samples impregnated filter paper (dried-spot) and kept at room temperature can be an excellent system for the detection and serotyping of S. pneumoniae in developing countries where lack of financial resources is a major constraint.
The ability of the pneumococcus to cause disease depends on the presence of a polysaccharide capsule that prevents phagocytosis. Although the presence of the capsule is a requirement to produce disease, is not sufficient to confer virulence, but need a large number of additional factors such as adhesins, proteases, toxins, transportation systems and enzymes that modify the extracellular medium. One recently identified pneumococcal virulence determinant is the pneumococcal serine-rich repeat protein (PsrP). This is an adhesin involved in adherence of pneumococci to lung cells. PsrP is an important virulence factor capable of causing disease and a potential new vaccine candidate protein.
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Míra informovanosti a postoje rodičů k nadstandardnímu očkování dětí 0-3 roky v městě Příbram. / Level of awareness and attitudes of parents to above-standard vaccination of children 0-3 years in Přibram.PODLENOVÁ, Kateřina January 2013 (has links)
This thesis is concerned with the level of parents´ awareness and attitudes to above-standard vaccination of children from 0-3 years in Příbram. Among the optional vaccination of children from 0-3 years belong vaccination against pneumococcal disease, rotavirus infections, meningococcal invasive disease (caused by meningococcal of group C, A+C, or A, C, W 135 and Y, now also of group B), tick-borne encephalitis, varicella smallpox, influenza and hepatitis A (or a combination of type A + B). The first part deals with the issue in a theoretical perspective. It foreshadows the basic characteristics of the diseases against which the premium vaccination of children from 0-3 years is offered. Further it is focused on vaccines against these diseases, which can occur in the Czech Republic. The survey is summarized in the research. There were parents of children attending one of the 12 kindergartens in Příbram in the sample of the research. tely 40% of the parents (or mothers) of these children in each kindergarten.The results were summarized in schedules of absolute and relative frequencies, or graphs. It was set three basic goals that were met with five hypotheses. The first of these was to monitor the attitudes of parents to above-standard vaccination of children from 0-3 years in Příbram. To this target relate hypothesis H1: Parents are interested in above-standard vaccination of children from 0-3 years in Příbram, H2: Parents with higher educational level have significantly higher interest in above-standard vaccination of children from 0-3 years and H3: Parents are statistically significantly more interested in vaccination against tick-borne encephalitis than other extra vaccination of children from 0-3 years, due to an endemic area of tick-borne encephalitis in Příbram. These hypotheses were not confirmed statistically. The second aim investigated the main reason for the possible lack of interest in extra vaccination of children from 0-3 years in Příbram. The target was filled with hypothesis H4: The main reason for the possible lack of parents´ interest in extra vaccination of children from 0-3 years is high price of vaccines, which was statistically refuted. The third goal was to explore parents' knowledge about diseases against which the extra vaccination of children from 0-3 years is offered. To this goal was set the hypothesis H5: Parents have sufficient information about the diseases against which the extra vaccination of children from 0-3 years is offered. This hypothesis was confirmed. The hypotheses were verified by ?chi-square? test at a significance level of 5%, which is an instrument of verification or falsification of hypotheses. This work may be used in practice as a preview to the parents´ awareness and interest in extra vaccination of children from 0-3 years. As well as cumulative information materials for professionals and the public about the above-standard vaccination of children from 0-3 years.
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Immune response to Streptococcus pneumoniae polysaccharide vaccination and antigen-selected B cells in highly susceptible individualsLeggat, David Jason 20 August 2014 (has links)
No description available.
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