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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

A molecular investigation of the prevalence of suspected periodontopathogens and their association with preterm birth

Claude, Bayingana January 2010 (has links)
<p>More than 20 million infants in the world (15.5 % of all births) are born with low birth weight. Ninety-five % of them are in developing countries. Oral colonization of Gramnegative anaerobes has&nbsp / been implicated as a risk factor for preterm delivery of low birth weight (PLBW) infants. The objective of this study was to investigate the association between periodontal pathogens and pre-term&nbsp / delivery of low birth weight (PLBW) infants. The study sample included 200 randomly selected women admitted to the department of obstetrics-gynecology of the teaching hospital of Butare in&nbsp / Rwanda. Mothers were asked to complete a questionnaire in order to identify factors which might pose a health risk to them and their infants. Gingival crevicular fluid (GCF) was collected from each quadrant of the mother&rsquo / s month (using paper points) within 24 hours of delivery. Ten ml of foetal cord serum samples were collected at delivery and 10 ml of maternal serum samples were&nbsp / collected within 48 of delivery. GCF was examined by PCR for the presence of 5 periodontopathogens and ELISA was used for the evaluation of cytokines (IL-6 and IL-10) and immunoglobulins (IgM, IgG) in foetal cord and maternal blood against the periodontopathogens. P. intermedia showed significant associations either on its own or in combinations with most indicators of&nbsp / periodontal disease used in this study, while Aa and members of the red complex were significantly associated with gum bleeding and reduced frequency of tooth brushing. A strong association&nbsp / between PLBW and maternal and foetal cord serum sample levels of IL-10 was observed. Also, a good association was observed between PLBW and FCB sample levels of IL-6. Significant&nbsp / associations were observed between PLBW and maternal IgG against the different peridontopathogens. The findings of this study may suggest that the levels of maternal IgG and foetal IgM&nbsp / against the different periodontopathogens are associated with dissemination of maternal periodontopathogens to the foetus thereby illiciting an inflammatory response which contributes to&nbsp / PLBW. </p>
22

Epidemiological and Bacteriological Aspects of Spotted Fever Rickettsioses in Humans, Vectors and Mammals in Sweden

Elfving, Karin January 2013 (has links)
Rickettsiae are obligate intracellular gram-negative bacteria transmitted by arthropod vectors. Rickettsiae sometimes cause disease in humans, typically with high fever, headache and occasionally an eschar. In Sweden, Rickettsia helvetica, belonging to the spotted fever group, is the only tick-transmitted rickettsia found free in nature. The pathogenic roll of R. helvetica has not been fully investigated, but it has been implicated in aneruptive fever and cardiac disease. This thesis describes parts of the transmission pathways of rickettsiae in Sweden. Rickettsia infection rates in ticks collected from birds were analysed, and the birds’ role as disseminators and reservoirs was studied. We found that more than one in ten ticks was infected with rickettsia bacteria, predominantly R. helvetica, and that migrating birds contribute not only to long-distance dispersion of bacteria, but also to an inflow of novel and potentially pathogenic rickettsia species, in this case R. monacensis and R. sp. strain Davousti-like species, into Sweden. Further, wild and domestic animals were found to have seroreactivity against R. helvetica, which shows that they are exposed and susceptible to rickettsia. Their role as reservoirs has not been determined, yet they may indirectly be involved in transmission of rickettsia to humans by infected ticks feeding on them. The seroreactivity in humans was also studied. Patients investigated for suspected Borrelioses and blood donors had detectable antibodies against Rickettsia spp., with the highest prevalence detected in the suspected Borreliosis group. This shows that humans in Sweden are exposed to and develop an immune response against rickettsia. The suspicion that R. helvetica may cause severe symptoms was verified by a patient with subacute meningitis where the bacterium was shown for the first time to cause an invasive infection with CNS involvement and where the bacterium was isolated from the patient’s cerebrospinal fluid. Growth characteristics and morphology of R. helvetica were studied to better understand invasiveness and virulence. The findings indicate that the invasiveness is comparable with other rickettsia, though R. helvetica seems to have a stable but slightly slower growth.  Rickettsia helvetica is endemic in Sweden and therefore needs to be considered when investigating disease after a tick bite. / Rickettsia är en liten, strikt intracellulär, gramnegativ bakterie som sprids med vektorer som fästingar, löss och loppor. Bakterien kan orsaka Rickettsios hos människa, en sjukdom där de vanligaste symtomen är hög feber, huvudvärk, muskelvärk och i vissa fall ett bettmärke (eschar). I Sverige är Rickettsia helvetica, som tillhör spotted fever gruppen (SFG), den enda fästingöverförda rickettsia bakterien som hittats allmänt i naturen. Patogeniciteten för R. helvetica är ofullständigt utredd, men ”aneruptive fever” och hjärtmuskelinflammation har rapporterats. Avhandlingen beskriver delar av smittkedjan för SFG rickettsia i Sverige. Bakteriernas förekomst i fästingar plockade från fåglar har studerats, likaså det ekologiska tryck som flyttfåglars bärarskap av infekterade fästingar bidrar med när de korsar olika världsdelar. Mer än var tionde fästing var infekterad med rickettsia bakterier, i huvudsak R. helvetica. Det visade sig att flyttfåglar bidrar inte bara till långväga spridning av bakterier utan även till införsel av nya potentiellt patogena rickettsiaarter, i detta fall identifierades R. monacensis och en R. sp strain Davousti liknande art. Vidare analyserades seroreaktivitet mot Rickettsia helvetica hos både tamdjur och vilda djur, vilket visade på antikroppsutveckling, som uttryck för smittexposition, i mer än vart femte djur. Djurens roll som reservoar för bakterien är inte klarlagd, men oavsett är djuren indirekt involverade i spridningen av bakterien till människa via infekterade fästingar som suger blod. Seroreaktivitet hos människa har också studerats. Patienter, provtagna på grund av misstanke om borreliainfektion, samt blodgivare hade detekterbara antikroppar mot Rickettsiae, med högst prevalens i gruppen med misstänkt borreliainfektion. Fynden visar att människor i Sverige är exponerade för och utvecklar en immunreaktion mot rickettsia. Att R. helvetica skulle kunna ge allvarlig sjukdom verifieras av ett patientfall med subakut meningit där bakterien för första gången visats ge invasiv infektion med påverkan på nervsystemet (CNS engagemang) och där bakterien isolerats från patientens ryggmärgsvätska.  Morfologi och tillväxtegenskaper för R. helvetica undersöktes för att bättre förstå bakteriens invasivitet och virulens. Fynden indikerar att invasiviteten är jämförbar med andra rickettsiaarter men R. helvetica verkar ha en stabil men något långsammare tillväxt. Rickettsia helvetica är endemisk i Sverige och måste tas i beaktande vid sjukdomsutredning efter ett fästingbett.
23

A molecular investigation of the prevalence of suspected periodontopathogens and their association with preterm birth

Claude, Bayingana January 2010 (has links)
<p>More than 20 million infants in the world (15.5 % of all births) are born with low birth weight. Ninety-five % of them are in developing countries. Oral colonization of Gramnegative anaerobes has&nbsp / been implicated as a risk factor for preterm delivery of low birth weight (PLBW) infants. The objective of this study was to investigate the association between periodontal pathogens and pre-term&nbsp / delivery of low birth weight (PLBW) infants. The study sample included 200 randomly selected women admitted to the department of obstetrics-gynecology of the teaching hospital of Butare in&nbsp / Rwanda. Mothers were asked to complete a questionnaire in order to identify factors which might pose a health risk to them and their infants. Gingival crevicular fluid (GCF) was collected from each quadrant of the mother&rsquo / s month (using paper points) within 24 hours of delivery. Ten ml of foetal cord serum samples were collected at delivery and 10 ml of maternal serum samples were&nbsp / collected within 48 of delivery. GCF was examined by PCR for the presence of 5 periodontopathogens and ELISA was used for the evaluation of cytokines (IL-6 and IL-10) and immunoglobulins (IgM, IgG) in foetal cord and maternal blood against the periodontopathogens. P. intermedia showed significant associations either on its own or in combinations with most indicators of&nbsp / periodontal disease used in this study, while Aa and members of the red complex were significantly associated with gum bleeding and reduced frequency of tooth brushing. A strong association&nbsp / between PLBW and maternal and foetal cord serum sample levels of IL-10 was observed. Also, a good association was observed between PLBW and FCB sample levels of IL-6. Significant&nbsp / associations were observed between PLBW and maternal IgG against the different peridontopathogens. The findings of this study may suggest that the levels of maternal IgG and foetal IgM&nbsp / against the different periodontopathogens are associated with dissemination of maternal periodontopathogens to the foetus thereby illiciting an inflammatory response which contributes to&nbsp / PLBW. </p>
24

A molecular investigation of the prevalence of suspected periodontopathogens and their association with preterm birth

Claude, Bayingana January 2010 (has links)
Philosophiae Doctor - PhD / More than 20 million infants in the world (15.5 % of all births) are born with low birth weight. Ninety-five % of them are in developing countries. Oral colonization of Gramnegative anaerobes has been implicated as a risk factor for preterm delivery of low birth weight (PLBW) infants. The objective of this study was to investigate the association between periodontal pathogens and pre-term delivery of low birth weight (PLBW) infants. The study sample included 200 randomly selected women admitted to the department of obstetrics-gynecology of the teaching hospital of Butare in Rwanda. Mothers were asked to complete a questionnaire in order to identify factors which might pose a health risk to them and their infants. Gingival crevicular fluid (GCF) was collected from each quadrant of the mother’s month (using paper points) within 24 hours of delivery. Ten ml of foetal cord serum samples were collected at delivery and 10 ml of maternal serum samples were collected within 48 of delivery. GCF was examined by PCR for the presence of 5 periodontopathogens and ELISA was used for the evaluation of cytokines (IL-6 and IL-10) and immunoglobulins (IgM, IgG) in foetal cord and maternal blood against the periodontopathogens. P. intermedia showed significant associations either on its own or in combinations with most indicators of periodontal disease used in this study, while Aa and members of the red complex were significantly associated with gum bleeding and reduced frequency of tooth brushing. A strong association between PLBW and maternal and foetal cord serum sample levels of IL-10 was observed. Also, a good association was observed between PLBW and FCB sample levels of IL-6. Significant associations were observed between PLBW and maternal IgG against the different peridontopathogens. The findings of this study may suggest that the levels of maternal IgG and foetal IgM against the different periodontopathogens are associated with dissemination of maternal periodontopathogens to the foetus thereby illiciting an inflammatory response which contributes to PLBW. / South Africa
25

"A molecular investigation of the prevalence of suspected periodontopathogens and their association with preterm birth"

Bayingana, Claude January 2010 (has links)
Philosophiae Doctor - PhD / More than 20 million infants in the world (15.5 % of all births) are born with low birth weight. Ninety-five % of them are in developing countries. Oral colonization of Gramnegative anaerobes has been implicated as a risk factor for preterm delivery of low birth weight (PLBW) infants. The objective of this study was to investigate the association between periodontal pathogens and pre-term delivery of low birth weight (PLBW) infants. The study sample included 200 randomly selected women admitted to the department of obstetrics-gynecology of the teaching hospital of Butare in Rwanda. Mothers were asked to complete a questionnaire in order to identify factors which might pose a health risk to them and their infants. Gingival crevicular fluid (GCF) was collected from each quadrant of the mother’s month (using paper points) within 24 hours of delivery. Ten ml of foetal cord serum samples were collected at delivery and 10 ml of maternal serum samples were collected within 48 of delivery. GCF was examined by PCR for the presence of 5 periodontopathogens and ELISA was used for the evaluation of cytokines (IL-6 and IL-10) and immunoglobulins (IgM, IgG) in foetal cord and maternal blood against the periodontopathogens. P. intermedia showed significant associations either on its own or in combinations with most indicators of periodontal disease used in this study, while Aa and members of the red complex were significantly associated with gum bleeding and reduced frequency of tooth brushing. A strong association between PLBW and maternal and foetal cord serum sample levels of IL-10 was observed. Also, a good association was observed between PLBW and FCB sample levels of IL-6. Significant associations were observed between PLBW and maternal IgG against the different peridontopathogens. The findings of this study may suggest that the levels of maternal IgG and foetal IgM against the different periodontopathogens are associated with dissemination of maternal periodontopathogens to the foetus thereby illiciting an inflammatory response which contributes to PLBW.
26

Izolace DNA z vybraných zeleninových výrobků (paprika) / DNA isolation from selected vegetable products (paprika)

Gőghová, Sabína January 2018 (has links)
The diploma thesis deals with micromethod of DNA isolation from ten differently processing food products containing pepper (Capsicum annum). PCR ready DNA was isolated by magnetic particles PGMA functionalized by carboxyl groups from homogenates prepared in lysis buffer with CTAB. Quantity and quality of DNA was estimated using spectrophotometric measurements and verified using PCR methods with primers specific for plant rDNA. Quality of isolated DNA varied depending on processing technology. DNA isolated from smoked grinded peppers and from heat treated food products was degraded and amplified with primers F_26S and R_26S (PCR product 220 bp) in contrary to the primers F_18S and R_5.8S (PCR product 700 bp). DNA isolated from the other food products was amplified with primers F_18S and R_5.8S (PCR product 700 bp). PCR product from one grinded pepper (Žitavská paprika) was cloned and sequenced.
27

Mikrobiální lipázy a jejich využití / Microbial lipases and their application

Pavlačková, Jana January 2010 (has links)
This diploma thesis is focused on the study of the preparation for fat separators and wastewater pipes that contains the microorganisms with lipolytic activity. Theoretical part of this thesis describes lipases, microorganisms producing this enzymes and usage of lipases. In this part possibilities of identification of microorganisms are presented too. The practical part is concerned with the study of commercial preparation Sany Duo Spezial with proven presence of microorganisms with lipolytic activity. These microorganisms were identified by means of the PCR method. This method identified mictoorganisms like genus Bacillus sp. Next characterization of the preparation was focused on the determination of COD and the investigation of the influence of various conditions of culture medium on the lipases production and their activity. The effect of temperature, ions and pH was studied. Lipolytic activity was determine spectrophotometricaly with usage of p-nitrophenyllaurate whitch dissociates to yellow product p-nitrophenol.
28

Izolace DNA v kvalitě pro PCR z probiotických výrobků pro dětskou výživu / Isolation of PCR-ready DNA from probiotic products for baby nutrition

Mantlová, Gabriela January 2013 (has links)
The aim of thesis is focused on isolation of DNA in quality for polymerase chain reaction (PCR) and the identification of probiotic bacteria. From six probiotic supplements for children were isolated PCR-ready DNAs using magnetic carriers P(HEMA-co-GMA). Isolated DNA was amplified by genus-specific and species-specific primers. DNAs of Lactobacillus, Bifidobacterium and Streptococcus genera were identified as: L. acidophilus, L. rhamnosus, L. casei, B. bifidum, B. longum ssp. longum, B. breve, B. longum ssp infantis, B. animalis and S. thermophilus. The identification corresponded with the data declared by the producers.
29

Využití magnetických částic při izolaci DNA z vybraných tepelně zpracovaných výrobků rostlinného původu / The application of magnetic particles for DNA isolation from thermally processed food products

Hronová, Aneta January 2017 (has links)
The thesis has been focused on testing of micromethod of DNA isolation using magnetic particles from thermic-managed food products in a quality suitable for polymerase chain reaction (PCR). Currant jams were selected for the analysis. These were homogenized using plastic copist and stomacher in lysis buffer with cetyltrimethylammonium bromide (CTAB). The effect of chloroform-octanol and isopropanol in the preparation of homogenates was tested. Homogenates were used for DNA isolation by magnetic particles. Rough fraction of DNA was purified by binding on the magnetic particles after centrifugation of the CTAB complexes with proteins, polyphenols and polysaccharides. Two types of magnetic particles were tested: microparticles of poly(hydroxyethylmethacrylate-co-glycidylmethacrylate) - P(HEMA-co-GMA) and nanoparticles of iron oxides covered by poly(L-lysine) - PLL. Isolated DNA was analyzed spectrophotometrically - it was assessed its concentration and contamination by polyphenols and proteins. After that, amplification of the DNA was tested in PCR. Primers specific for plant ribosomal DNA were used. PCR products of expected length 700 bp were detected by agarose gel electrophoresis. It was shown that DNA isolated from currant jams using magnetic particles was in PCR-ready quality.
30

Pesquisa sentinela da introdução do vírus do Oeste do Nilo no Brasil pela análise de doadores de sangue do Amazonas e Mato Grosso do Sul / Sentinel survey of the introduction of West Nile virus in Brazil by analyzing blood donors of Amazonas and Mato Grosso do Sul

Geraldi, Marcelo Plaisant 18 September 2012 (has links)
O vírus do Oeste do Nilo (VON) é um Flavivírus capaz de infectar muitas espécies de vertebrados, incluindo o homem. Embora reconhecida desde 1940, esta virose nunca havia sido descrita nas Américas, onde emergiu nos Estados Unidos ao final da década de 1990, com numerosos casos de meningoencefalite em humanos. Posteriormente, sua transmissão por transfusão de sangue e órgãos foi comprovada, levando à implantação de testes moleculares (NAT) para a triagem de doadores nos EUA e Canadá a partir de 2003. Nos anos seguintes, o VON foi sendo progressivamente detectado em países como México, Panamá e áreas do Caribe, sugerindo sua iminente introdução na América do Sul. De fato, evidências sorológicas foram reveladas em cavalos e aves na Colômbia, Venezuela, Argentina e muito recentemente no pantanal mato-grossense (em cavalos). A vigilância epidemiológica para este agente é de grande importância para a saúde pública, visto o potencial de morbimortalidade deste vírus para humanos. Sendo assim este trabalho tem o objetivo de investigar a presença do RNA do VON em amostras de doadores de sangue, pacientes com meningoencefalite ou febre de origem indeterminada e soros e amostras cerebrais de equinos. Foram analisadas 2.202 doações de sangue do Amazonas (HEMOAM), 3.144 do Mato Grosso do Sul (HEMOSUL); líquido cefalorraquidiano de 51 pacientes com suspeita de meningoencefalite viral (Hospital das Clínicas/FMUSP, São Paulo) e soro de 198 pacientes com síndrome febril aguda, negativos para Dengue e Malária (Fundação de Medicina Tropical de Manaus). Além disto, 293 amostras de soros de equinos da região do Pantanal e 63 biópsias de tecido cerebral de cavalos que foram a óbito por encefalite de etiologia desconhecida. Estas amostras foram submetidas ao teste automatizado cobas TaqScreen WNV (Roche) na plataforma cobas s201 em sistema de pool de 6 unidades (doações de sangue) ou individualmente (pacientes). Todas as amostras apresentaram amplificação satisfatória do controle da reação, porém nenhuma apresentou resultado positivo para a presença do RNA do VON. Embora já exista evidência da exposição de equinos no Brasil ao VON, não parece haver até o momento, disseminação importante deste agente entre humanos e equinos, uma vez que o RNA viral não foi detectado nem em doadores de sangue e nem em equinos, incluindo os de cidades próximas aos locais onde cavalos soropositivos foram encontrados (Corumbá MS). / The West Nile Virus (WNV) is a Flavivirus able to infect many species of vertebrates, including man. Recognized since 1940, this virus had never been described in the Americas, which emerged in the United States at the end of the 1990s, with numerous cases of meningoencephalitis in humans. Later, transmission by transfusion of blood and organs was confirmed, leading to the deployment of molecular testing (NAT) for screening of donors in the U.S. and Canada since 2003. In the following years, WNV has been progressively detected in countries like Mexico, Panama and the Caribbean areas, suggesting their imminent introduction in South America In fact, serological evidence was revealed in horses and birds in Colombia, Venezuela and Argentina and most recently in Pantanal, Mato Grosso (horses). Epidemiological surveillance for this agent is of great importance to public health, given the potential morbidity and mortality of this virus to humans. Therefore this study aims to investigate the presence of WNV RNA in samples of blood donors, patients with meningoencephalitis or fever of unknown origin and serum and brain samples from horses. We analyzed 2202 blood donations from Amazon (HEMOAM), 3144 from Mato Grosso do Sul (HEMOSUL); cerebrospinal fluid of 51 patients with suspected viral encephalitis (Hospital das Clínicas / FMUSP, São Paulo) and serum samples from 198 patients with acute febrile syndrome, negative for Dengue and malaria (Foundation for Tropical Medicine in Manaus). In addition, more 293 serum samples from horses of the Pantanal and 63 biopsies of brain tissue from horses that died of encephalitis of unknown etiology. These samples were subjected to automated cobas TaqScreen WNV test (Roche) on the platform in cobas S201with a system of 6 units pool (blood donations) or individually (patients). All samples showed satisfactory control amplification, but none showed as positive for the presence of RNA VON. Although there is already evidence in horses in Brazil of exposure to WNV, there seems to be far that an important spread of this agent between humans and horses, since the viral RNA was not detected either in blood donors or in horses, including cities near the locations where seropositive horses were found (Corumbá - MS).

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