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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

Mikrosatellitenalterationen in der Serum-DNA bei Patienten mit Bronchialkarzinom

Bruhn, Norbert 20 October 1999 (has links)
Die Bedeutung von Mikrosatellitenalterationen in malignen Tumoren ist trotz intensiver Forschungstätigkeit bisher nicht ausreichend geklärt. Bei Patienten mit einem hereditären nichtpolypösen kolorektalen Karzinom-Syndrom (HNPCC) konnte aber ein möglicherweise kausaler Zusammenhang zwischen einer Keimbahnmutation der Gene, die an dem DNA-"mismatch"-Reparaturmechanismus beteiligt sind, und der Ätiologie dieser Erkrankung nachgewiesen werden. Der Nachweis von Mikrosatelliteninstabilitäten wird zur Identifizierung des HNPCC-Syndroms genutzt. Der Anteil nachgewiesener Mikrosatelliteninstabilitäten bei sporadischen Tumorerkrankungen ist deutlich niedriger als beim HNPCC-Syndrom. Die Mechanismen zur Entstehung von Mikrosatelliteninstabilitäten bei sporadischen Tumor-erkrankungen sind bisher ungeklärt. Der gelungene Nachweis von Mikrosatellitenalterationen im Serum, Fäzes, Urin und Sputum von Tumorpatienten könnte das diagnostische Repertoire erweitern und möglicherweise die frühzeitige Erkennung von Tumorerkrankungen verbessern. Eine auf eine PCR basierende Methode zur Analyse von Mikrosatellitenalterationen in Tumor- und Serumproben wurde in dieser Arbeit etabliert. Drei Mikrosatellitenmarker (AR, ACTBP2, UT762) wurden bei der Untersuchung eingesetzt. Es wurden Tumor- und Serum-DNA mit der DNA von Lymphozyten verglichen und analysiert. Es wurden 43 Patienten mit Bronchialkarzinom untersucht, darunter 16 Patienten mit kleinzelligem und 27 Patienten mit nichtkleinzelligem Bronchialkarzinom. Es wurden bei 5 von 16 (31 %) Patienten mit SCLC und bei 9 von 27 (33 %) Patienten mit NSCLC in mindestens einem Mikrosatellitenlocus eine Mikrosatelliteninstabilität oder ein LOH nachgewiesen. In der Kontrollgruppe mit gesunden Probanden waren keine Mikrosatellitenalterationen nachweisbar. Die unverändert sehr schlechte Prognose von Patienten mit Bronchialkarzinom unterstreicht die Notwendigkeit der Entwicklung einer zuverlässigen und sensitiven Methode zur verbesserten Frühdiagnostik. Dazu wird es notwendig sein, weitere Mikrosatellitenmarker hinsichtlich ihrer Tumorsensitivität und -spezifität an einer ausreichenden Anzahl von Patienten zu testen und die prognostische Bedeutung von Mikrosatellitenalterationen bei Patienten mit einem Bronchialkarzinom zu klären. / Background: Despite intensive research efforts, the significance of microsatellite alterations in malignant tumors is not sufficiently understood. Since a possible causal connection between disease etiology and a germination mutation of the genes, involved in the mismatch repair mechanism, could be demostrated in patients with hereditary nonpolyposis colorectal cancer (HNPCC), the detection of microsatellite instabilities may be used to identify the so-called HNPCC syndrome. While the amount of proven microsatellite instabilities in sporadic tumor diseases is significantly lower than in the HNPCC syndrome, the mechanisms generating these instabilities have not been clarified yet. Their succesful measurement in serum, feces, urine, and sputum would extend the diagnostic repertory for tumor patients and possibly improve the early detection of neoplastic disease or its recurrence. Results: In this thesis, a PCR-based method was established for the analysis of microsatellite alterations in tumor specimens and serum samples. Three microsatellite markers were employed, including AR, ACTBP2, and UT762. The DNA of tumors and serum was analyzed and compared with the DNA of lymphocytes. Specimens of 43 patients with bronchial carcinoma (16 small cell lung carcinoma (SCLC), 27 non-small cell lung carcinoma (NSCLC)) were examined. In 5 of the patients with SCLC (31%) and in 9 of those with NSCLC (33%) a microsatellite instability or a loss of heterozygosity (LOH) was demonstrated in at least one microsatellite locus. The controls, which included samples of serum and lymphocytes of 10 healthy volunteers, did not show any microsatellite alterations. Outlook: The still poor prognosis of patients with bronchial carcinoma warrants further development of sensitive and reliable methods to improve early detection. Beyond this study, further microsatellite markers need to be tested in a sufficient number of patients with respect to sensitivity and specificity of tumor diagnosis. In addition, the prognostic significance of microsatellite alterations in tumor patients requires further investigation.

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