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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.
471

Seropositividad a Helicobacter pylori y su relación con náusea y vómitos durante las primeras 20 semanas del embarazo

Castillo Contreras, Ofelia, Maguiña Quispe, Jorge, Medina Morales, Bryan, Malaverry Lozano, Héctor 12 1900 (has links)
Existen estudios que encontraron mayor prevalencia de anticuerpos contra Helicobacter pylori (Hp) en gestantes con hiperémesis gravídica, en comparación con mujeres embarazadas asintomáticas. Objetivos. Determinar la relación entre la seropositividad a Hp y la presencia de náusea y vómitos durante las primeras 20 semanas del embarazo en gestantes de una red hospitalaria, entre marzo y diciembre de 2015. Material y métodos. Estudio de casos y controles no pareado en gestantes hasta las 20 semanas de embarazo. El índice de Rhodes para náusea y vómitos clasificó a las gestantes en casos (9-40 puntos) y en controles (8 puntos). La seropositividad a Hp fue definida como IgG ≥ 1,1 U/mL. La asociación entre Hp y náusea y vómitos del embarazo se determinó con el análisis de regresión logística, controlando por edad, paridad, edad gestacional y nivel socioeconómico. Resultados. Un total de 108 pacientes fueron incluidas, 21 controles y 87 casos. No hubo diferencias significativas en edad (p = 0,916), paridad (p = 0,18) y nivel socioeconómico (p = 0,36). La seropositividad a Hp en los casos fue 78,2% (68/87) y en los controles 61,9% (13/21). En el análisis de regresión logística, los casos presentaron mayor riesgo de seropositividad a Hp que los controles (OR = 3,05; IC 95%: 0,92-10,1; p = 0,068), pero no fue significativa. Conclusiones. Las pacientes con náusea y vómitos en las primeras 20 semanas de gestación tuvieron un mayor riesgo de haber estado expuestas a Hp, aunque esta relación no fue significativa debido al pequeño tamaño de muestra. / There are studies that found a higher prevalence of antibodies against Helicobacter pylori (Hp) in patients with hyperemesis gravidarum, compared to asymptomatic pregnant women. Objective. To determine the relationship between seropositivity to Hp and the presence of nausea and vomiting during the first 20 weeks of gestation in pregnant women of a hospital network, from March to December 2015. Material and methods. Unmatched case-control studies in pregnant women until 20 weeks of gestation. The Rhodes’ index for nausea and vomiting classified pregnant women in cases (9-40 points) and controls (8 points). Hp seropositivity was defined as IgG ≥ 1.1 U/mL. The association between Hp and nausea and vomiting of pregnancy was determined by logistic regression analysis controlling for age, parity, gestational age and socioeconomic status. Results. A total of 108 patients were included, 21 controls and 87 cases. There were no significant differences in age (p = 0.916), parity (p = 0.18) and socioeconomic status (p = 0.36). Hp seropositivity in cases was 78.2% (68/87) and controls 61.9% (13/21). In the logistic regression analysis, cases had higher risk of Hp seropositivity than controls (OR = 3.05; 95% CI: 0.92-10.1; p = 0.068), but was not significant. Conclusions. Patients with nausea and vomiting in the first 20 weeks of gestation had a higher risk of having been exposed to Hp, although this relationship was not significant due to the small sample size.
472

Helicobacter Pylori Restriction-Modification Systems : Possible Roles Beyond Genome Protection

Kumar, Ritesh 05 1900 (has links) (PDF)
Helicobacter pylori is one of the most potential and successful human pathogen which colonizes atleast 50% of world population. One of the important characteristics of this pathogen is the degree of allelic diversity and genetic variability which helps it to adapt and colonize. Phase variation is one of the mechanisms used by Helicobacter pylori to generate variation, where presence of homopolymeric nucleotide or dinucleotide repeats in an ORF make it prone to frequent length changes as a consequence of slipped strand mispairing mediated mutagenesis. An important feature of H. pylori biology is the presence of a large number of Restriction-Modification (R-M) systems in its genome. Till date, seven strains have been completely sequenced and each have more than 20 R-M systems. The presence of homopolymeric nucleotide or dinucleotide repeats in many of R-M systems make them an interesting subject for investigation. Here, we show that hp0051 which codes for a C5 cytosine methyltransferase from H. pylori is a hypermutable gene, which undergoes random mutations. In addition it exhibits phase variation due to presence of a dinucleotide (AG) repeat which results in a truncated protein. hp0051 homologs were amplified and sequenced from different clinical isolates of H. pylori. Sequence analysis showed that hp0051 homologs from 23 clinical isolates are different from each other suggesting a hypervariable nature of the sequence. It was observed that when over expressed in E. coli hp0051 undergoes random mutations. These mutations give rise to different variants of HP0051 with different biochemical properties. Different variants of HP0051 were biochemically characterized. All variants recognize 5´-CCTC-3´ and methylate the first cytosine. A few of the isoforms exhibit degeneracy in the recognition site as they recognize 5´- CNCC-3´ (N being any nucleotide) and methylates third cytosine. Molecular modelling studies suggest that HP0051 has two domains, one large domain having catalytic and AdoMet binding motifs and small domain having target recognition domain. DNA sequencing, peptide finger mapping, MALDI MS-MS and CD have been used to establish the differences between the different isoforms of HP0051. Interestingly when a mutant protein which lacks methylation activity was expressed in E.coli random mutations were not observed. To understand the role of methylation in the occurrence of random mutations, microarray analysis was done. Microarray analysis have shown that the overexpression of HP0051 results in the down regulation of deoxyadenine methyltransferase (dam) in E.coli. Microarray data were further authenticated by RT PCR analysis. dam plays a vital role in mismatch repair pathway and down regulation of dam results in enhanced mutation rates. A large number of clinical isolates were analysed for the presence of hp0051 and hp0051 was found to be present in 83% of strains obtained from patients compared to 25 % of strains from healthy volunteers. Single colonies obtained from the same patient were analysed and it was found that variation in hp0051 exists within a patient also. Deletion of an orphan C5 cytosine methyltransferase, hp0051 in H. pylori strains 26695, SS1 and 98.4 has a significant effect on the expression of number of genes belonging to motility, adhesion and virulence. 98.4∆hp0051 mutant strain has a different LPS profile and is able to induce high IL-8 production compared to wild-type. H. pylori strain 26695∆hp0051 is more motile than the wild- type. hp0051 from strain 26695 is able to complement mutant SS1 and 98.4 strains. This study highlights the possible significance of cytosine methylation in the physiology of H. pylori. hp0050 is a N6 DNA adenine methyltransferase which overlaps with the hp0051 ORF .hp0050 was cloned, over expressed and purified to near homogeneity. It recognizes the sequence 5´GRRG 3´ (where R is A or G) and most intriguingly methylates both adenines when R is A (5´GAAG 3´). Kinetic analysis suggest a non processive (repeated hit) mechanism of methylation in which HP0050 methyltransferase methylates one adenine at a time in sequence 5´GAAG 3´. Interestingly, HP0050 homologs from two clinical strains PG227 and 128 methylate only 5´GAGG 3´ compared to 5´GRRG 3´ in strain 26695. HP0050 MTase is highly conserved as it is present in more than 90% of strains. Inactivation of hp0050 in strain PG227 resulted in poor growth suggesting its important role in the physiology of Helicobacter pylori. Collectively, these findings provide impetus for exploring the role(s) of this conserved DNA methyltransferase in the cellular processes of Helicobacter pylori. In one of the clinical isolate it was found that hp0051 and hp0050 can code for a single polypeptide due to an insertion mutation. This mutant ( hp0050 and hp0051 fusion ) was cloned, overexpressed and purified. It was found that fusion protein is able to methylate both adenine and cytosine in the cognate sequence. Similarly, hp1369 - hp1370 is a phase variable type III MTase and it belongs to ɛ group of MTases based on the arrangement of motifs. It has a poly G repeat in its ORF and any change in the number of repeats can result in a functional (full length) or non functional (truncated) protein. Within strain 26695, it has 10 G repeat which results in a truncated protein. Addition of a single nucleotide by site directed mutagenesis in the repeat results in a full length functional protein. HP1369_HP1370 fusion protein recognizes and methylates 5´ TCAGC 3´. DNA methyltransferases are known to play a critical role in gene regulation, cell cycle regulation and pathogenesity in a number of pathogens. H. pylori genome is rich in DNA methyltransferases and this study shows that these methyltransferases exhibit unique features like phase - variation and polymorphism .We propose that high degree of variation that exists in these methyltransferases could play a vital role in enhancing the ability of H. pylori to adapt its host.
473

Helicobacter pylori em pacientes com ulcera peptica e gastrite cronica : : detecção pela Nested PCR e pela PCR e genotipagem pelos genes Urease C e Urease B / Helicobacter pylori in patients with peptic ulcer and chronic gastritis: detection by nested PCR and by PCR and genotyping by genes Urease C and Urease B

Roesler, Bruna Maria 24 August 2006 (has links)
Orientador: Sandra Cecilia Botelho Costa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-07T12:19:53Z (GMT). No. of bitstreams: 1 Roesler_BrunaMaria_M.pdf: 3428404 bytes, checksum: ee37171bd6740210c88477c4839317fb (MD5) Previous issue date: 2006 / Resumo: O Helicobacter pylori é uma bactéria gram-negativa que está estritamente relacionada com o desenvolvimento de doenças gástricas, inclusive malignas, sendo classificada como carcinógeno do grupo I pela Agência Internacional para Pesquisa do Câncer. Apesar de grande parte da população mundial estar contaminada pela bactéria, a maioria dos indivíduos permanece assintomática. Muitas abordagens são sugeridas para diferenciar os isolados de H. pylori e diversas técnicas de biologia molecular têm sido aplicadas para caracterizar as amostras clínicas de diferentes pacientes. A análise de restrição (RFLP) usada em conjunto com a PCR tem sido amplamente utilizada para a tipagem de isolados clínicos, utilizando vários genes do genoma do H. pylori como alvos para esse método. Padrões de eletroforese da nested PCR e da PCR para as regiões dos genes urease C e urease B do H. pylori foram obtidos com enzimas de restrição e comparados entre pacientes com úlcera péptica e gastrite crônica. Os produtos da nested PCR para urease C foram digeridos com a enzima Mbo I e os produtos da PCR para urease B com a enzima Hae III, sendo os fragmentos obtidos analisados por eletroforese em gel de agarose. Foram encontrados 7 padrões de genotipagem para urease B e 17 padrões para urease C. O grupo prevalente para gastrite crônica obtido com essa última genotipagem foi o denominado grupo ureC MboI G, com fragmentos de 110, 120, 250 e 310 pares de bases, ocorrendo em 13 pacientes (15,7% dos casos). Em relação aos casos de úlcera péptica, o grupo de genotipagem mais prevalente foi o denominado ureC MboI E, com 110, 180 e 500 pares de bases, ocorrendo em 11 pacientes (24,4% do total de casos). O grupo prevalente obtido com a genotipagem para urease B foi o denominado ureB I, com um fragmento único de 750 pares de bases. Esse grupo foi o prevalente tanto para os casos de úlcera péptica (27), com 60,0%, quanto para os de gastrite crônica (53), com 63,9%. Não foram observadas diferenças significativas entre os padrões encontrados para ambas as doenças. A nested PCR para detecção prévia do DNA do H. pylori também foi realizada, obtendo-se 100% de concordância. Os métodos de tipagem dos produtos obtidos por nested PCR e PCR proporcionam um esquema funcional e de grande reprodutibilidade para estudos epidemiológicos e de caracterização de cepas / Abstract: Helicobacter pylori is a gram-negative bacterium that has been implicated as a major human gastric pathogen responsible for gastritis and peptic ulcer disease. It has been classified as a group I carcinogen by the International Agency for Research on Cancer and is regarded as a primary factor for gastric cancer. A significant proportion of the world population is infected with H. pylori, even though most infections are asymptomatic. To isolate H. pylori, many approaches have been presented and several molecular techniques have been applied to separate clinical isolates from different patients. PCR-RFLP analysis has been widely developed for the typing of clinical isolates, with several genes within H. pylori having been targeted by this method. Eletroforesis patterns of nested PCR and PCR to urease C and urease B gene regions of H. pylori were obtained by restriction fragment length polymorphism and compared among patients with peptic ulcer and chronic gastritis. Nested PCR products for urease C were digested with MboI enzyme and PCR products for urease B with Hae III enzyme, and the obtained fragments were analyzed by eletroforesis in agarosis gel. We have encountered 7 genotyping patterns for urease B and 17 patterns for urease C. The prevalent group for chronic gastritis which was obtained with this last genotyping was named ureC MboI G group, with fragments of 110, 120, 250 and 310 base pairs, occurring in 13 patients (15,7% of the cases). Regarding the peptic ulcer cases, the most prevalent genotyping group was named ureC MboI E group, with 110, 180 and 500 base pairs, occurring in 11 patients (24,4% of the cases). The prevalent group obtained with the genotyping for urease B was named ureB I, with only one fragment of 750 base pairs. This group was the prevalent one both in peptic ulcer cases (27) with 60,0%, and in chronic gastritis case (53), with 63,9%. We haven¿t found meaningful differences among the encountered patterns for both diseases. Nested PCR for previous detection of H. pylori DNA has also been performed, and we have obtained 100% of concordance. The typing methods of the products obtained by nested PCR and PCR show a functional scheme and of great reproduction for epidemiologic studies and of H. pylori strains characterization / Mestrado / Mestre em Farmacologia
474

Ancestría versus selección: Infección con Helicobacter pylori en la Población chilena

Frías Villarroel, Liesbeth. January 2010 (has links)
No description available.
475

DETECCIÓN Y VIABILIDAD DE Helicobacter pylori EN AGUAS CRUDAS Y POTABLES EN TRES PLANTAS DE POTABILIZACIÓN EN LA CIUDAD DE BOGOTÁ

Vesga Pérez, Fidson Juarismy 10 September 2018 (has links)
Helicobacter pylori es una bacteria capaz de colonizar la mucosa gástrica, produciendo una de las infecciones más frecuentes en la población, con una prevalencia global del 50%, que alcanza el 70-80% en Colombia. El objetivo de este estudio fue determinar la presencia, viabilidad y virulencia de H. pylori en aguas crudas y potables de tres plantas potabilizadoras de la ciudad de Bogotá. Para ello, se evaluaron 310 muestras (155 de cada matriz) mediante las técnicas de cultivo, PCR convencional, qPCR y FISH. También se evaluaron indicadores de contaminación fecal y parámetros fisicoquímicos. Se demostró la presencia de células cultivables de H. pylori en 56 de las 310 muestras de las tres plantas de potabilización (11-24%). También se detectó ADN de H. pylori en las 3 plantas por PCR convencional y qPCR (15-27% de las muestras de agua cruda y 24-31% de agua potable). Por qPCR fue posible cuantificar H. pylori en 13 (8.4%) muestras de agua cruda y en 20 (12.9%) de agua potable. El genotipo de H. pylori más prevalente en el agua fue vacA m1/s1. No se encontró relación entre los indicadores de contaminación fecal y la presencia de H. pylori en el agua cruda ni potable. Tampoco se encontró relación entre el pH, la conductividad, la turbidez y el cloro residual de las muestras y la presencia y/o ausencia de H. pylori. Los resultados de este estudio demuestran que células viables de H. pylori están presentes tanto en el agua de entrada como en la de salida de las plantas potabilizadoras analizadas, pudiendo ser estas un vehículo de transmisión del patógeno. Sin embargo, para evauluar el riesgo real al que está expuesto el consumidor, deben realizarse otros estudios que evalúen el potencial infeccioso de estas células. / Helicobacter pylori is a bacteria able to colonize the gastric mucosa, producing one of the most common infections in the population, with a global prevalence of 50% which reaches 70%-80% in Colombia. The objective of the present study was to determinate the presence, viability and virulence of H. pylori in raw and drinking waters of three water treatment plants in the city of Bogotá. For this purpose, 310 water samples (155 of each type of water) were evaluated by culture, conventional PCR, qPCR and FISH techniques. Fecal indicators and physic-chemical parameters were also evaluated. The presence of cultivable H. pylori cells was demonstrated in 56 out of the 310 samples coming from the three water treatment plants (11-24%). H. pylori DNA was also detected by conventional PCR and q PCR (15-27% of raw water and 24-31% of drinking water samples); by qPCR it was possible to quantify H. pylori in 13 (8.4%) samples of raw water and in 20 (12.9%) of drinking water. The H. pylori vacA m1/s1 genotype was the most prevalent among the analyzed water samples. Regarding the fecal indicators and the presence of H. pylori, no relation was found in either raw or drinking water. No association was found between pH, the conductivity, turbidity and residual chlorine of the samples and the presence and/or absence of H. pylori. Results obtained in this research demonstrate that viable H. pylori cells are present both in raw and drinking water of the analyzed water treatment plants being those able to be vehicle of transmission of the pathogen. However, in order to assess the real risk to which the consumer is exposed, other studies should be carried out to evaluate the potential infectious of these cells. / Helicobacter pylori es una bactèria capaç de colonitzar la mucosa gàstrica, produint una de les infeccions més freqüents en la població, amb una prevalença global del 50%, i del 70-80% a Colòmbia. L'objectiu d'este estudi va ser determinar la presència, viabilitat i virulència de H. pylori en aigües crues i potables de tres plantes potabilitzadores de la ciutat de Bogotà. Per a aquest propòsit, es van avaluar 310 mostres (155 de cada matriu) per mitjà de les tècniques de cultiu, PCR convencional, qPCR i FISH. També es van avaluar indicadors de contaminació fecal i paràmetres fisicoquímics. Es va demostrar la presència de cèl·lules cultivables de H. pylori en 56 de les 310 mostres de les tres plantes potabilitzadores (11-24%). També es va detectar ADN de H. pylori a les 3 plantes per PCR convencioanl i qPCR (15-27% de les mostres d'aigua crua i 24-31% d'aigua potable). Per qPCR va ser possible quantificar H. pylori en 13 (8.4%) mostres d'aigua crua i en 20 (12.9%) d'aigua potable. El genotip de H. pylori més prevalent en l'aigua va ser el vacA m1/s1. No es va trobar relació entre els indicadors de contaminació fecal i la presència de H. pylori ni a l'aigua crua ni a la potable. Tampoc es va trobar relació entre el pH, la conductivitat, la terbolesa i el clor residual de les mostres i la presència i/o absència de H. pylori. Els resultats d'aquest estudi demostren que hi ha cèl·lules viables de H. pylori tant en l'aigua d'entrada com en la d'eixida de les plantes potabilitzadores analitzades, i podent ser aquestes un vehicle de transmissió del patogen. Malgrat això, per a avaluar el risc real a que s'exposa el consumidor, han de realitzar-se altres estudis que avaluen el potencial infecciós d'aquestes cèl¿lules. / Vesga Pérez, FJ. (2018). DETECCIÓN Y VIABILIDAD DE Helicobacter pylori EN AGUAS CRUDAS Y POTABLES EN TRES PLANTAS DE POTABILIZACIÓN EN LA CIUDAD DE BOGOTÁ [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/107957 / TESIS
476

Indolent feature of Helicobacter pylori-uninfected intramucosal signet ring cell carcinomas with CDH1 mutations / ヘリコバクターピロリ未感染胃に発生するCDH1変異粘膜内印環細胞癌は進行が遅い特徴を持つ

Nikaido, Mitsuhiro 24 September 2021 (has links)
京都大学 / 新制・論文博士 / 博士(医学) / 乙第13442号 / 論医博第2241号 / 新制||医||1054(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 羽賀 博典, 教授 藤田 恭之, 教授 伊藤 貴浩 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
477

Organoid Models of Digestive Diseases

Holokai, Loryn 14 October 2019 (has links)
No description available.
478

Evaluación fitoquímica y actividad anti-helicobacter pylori del aceite esencial de Minthostachys mollis “muña” en pacientes con gastritis del Hospital Militar Central

Rojas Wisa, Oscar Favio January 2017 (has links)
Realiza la evaluación fitoquímica y la actividad anti-Helicobacter pylori del aceite esencial de Minthostachys mollis “muña” en pacientes del Hospital Militar Central diagnosticados con gastritis. Las hojas de M. mollis se recolectaron en Tranca (3300 m.s.n.m.), distrito de Vinchos, provincia de Huamanga, Región Ayacucho. Se extrajo el aceite esencial (AE) por arrastre con vapor de agua, resultando con un rendimiento de 2,00 %v/p, densidad 0,9041 g/mL, índice de refracción 1,56689 a 20 ºC. La composición química fue determinada por el método cromatografía de gases acoplada a espectrometría de masas, resultando: D-mentona (39,75 %), pulegona (22,45 %), (2S-trans)-5-metil-2-(1-metiletil) - (ciclohexanona (10,24 %), β-linalol (3,33 %) y neomentol (2,13 %). Por el método de Artemia salina se evaluó la bioactividad y citotoxicidad, mostrando una CL50=15,24 mg/Kg. La dosis letal media oral aguda (DL50) = 2,21 mL/kg, en ratas albinas de acuerdo al método de dosis límite, catalogada de baja toxicidad. A los tres grupos en estudio se administró vía oral por diez días cápsulas de gelatina aceite esencial de M. mollis, 300 mg, 700 mg y 1000 mg + omeprazol 40 mg respectivamente usándose como vehículo el aceite de Plukenetia volubilis “sacha inchi”; al grupo de control positivo se suministró por vía oral en dosis diaria cápsulas de amoxicilina 1500 mg + claritromicina 1000 mg + omeprazol 40 mg, durante diez días. Al grupo control negativo se administró por vía oral en dosis diaria aceite de P. volubilis en cápsulas en iguales condiciones. Después de 30 días de tratamientos se realizó una endoscopia alta para el control a todos los grupos en estudio; con el tratamiento clásico antibióticos + omeprazol se observó la erradicación de la mencionada bacteria y con el tratamiento de AE + omeprazol no se observó la erradicación. Se concluye que el aceite esencial de Minthostachys mollis “muña” bajo las condiciones de este ensayo no presenta actividad anti-Helicobacter pylori. / Tesis
479

Assessing cardiotonic steroids involvement in hypertensive rat models with Helicobacter pylori infections

Masso, Zelie Flavienne 31 July 2020 (has links)
Introduction: Hypertension is an important public health challenge worldwide, being the leading cause of cardiovascular disease, morbidity and mortality. It is particularly prevalent in people in sub-Saharan Africa, especially in urban areas. There is an urgent need to develop strategies to prevent, detect, treat, and control hypertension effectively in the African region. Helicobacter pylori, a gram-negative bacterium responsible for many gastric disorders worldwide, has been associated with hypertension in some previous studies; where blood pressure of patients with Helicobacter pylori infection did not subside after hypertensive treatment, when compared to patients without Helicobacter pylori infections. This effect was suggested to be due to Helicobacter pylori produced and modified cardiotonic steroids that are found in elevated concentrations in hypertensive patients. Cardiotonic steroids are positive inotropic agents which are known to increase blood pressure. A sensitive analytical method is needed to detect and quantify the low concentrations of cardiotonic steroids in biological samples. Materials and Methods: An extraction method was optimised using reversed phase Solid Phase Extraction. A targeted liquid chromatography tandem mass spectrometry method using an Agilent binary series 1100/1200 LC system with a Kinetex C18 RP column (100 x 2.1 mm, 2.6 µm) coupled to a Sciex 4000QTRAP tandem mass spectrometer was developed and validated for the detection and quantitation of 9 different cardiotonic steroids in both solvent and whole blood. The method was validated according to the International Conference on Harmonization guidelines with regards to precision, accuracy, sensitivity, selectivity, linearity, range, limit of detection, limit of quantification, reproducibility, recovery, carry-over and stability. Media from Helicobacter pylori cultures and faecal samples from human and different normo- and hypertensive rat strains were analysed. Data analysis was performed with Analyst® Software (version 1.5.2) and multiple t-test and Kruskal Wallis test using GraphPad Prism 8 software. Results and Discussion: The calibration curves of tested cardiotonic steroids were linear over a concentration range of 0.1-40 ng/mL with coefficients of determination greater than 0.990 except for telocinobufagin. The analytical method was selective with an estimated limit of detection and limit of quantification between 0.02-0.5 ng/mL and 0.1-2 ng/mL respectively. All tested cardiotonic steroids showed good recovery of over 70%. Accuracy and precision were found to be within acceptable limits of 15% and 20% at lowest limit of quantification for almost all the analytes and their stability in blood and solvent at room temperature, 4°C, -20°C and -80°C was tested for a month. Cardiotonic steroids were detected in Helicobacter pylori cultures and faecal samples with the exception of ouabain and proscillaridin A which were not detected at all. Although Helicobacter pylori were shown to produce cardiotonic steroids in vitro, no evidence of the effect of Helicobacter pylori on cardiotonic steroids production was detected in different normo- and hypertensive rat groups. Conclusion: The quantitative analytical method was successfully validated, over expected in vivo concentration ranges for 8 different cardiotonic steroids. The extraction and analytical methods were both successfully applied to Helicobacter pylori cultures and faecal rat samples where cardiotonic steroids were detected. / Dissertation (MSc)--University of Pretoria 2020. / National Research Foundation Student bursary / Pharmacology / MSc (Pharmacology) / Unrestricted
480

Nachsorge bei gastralen MALT-Lymphomen nach alleiniger Helicobacter pylori-Eradikation unter besonderer Berücksichtigung der Patientencompliance / Adherence to follow-up of patients with Gastric-MALT-Lymphoma treated by Helicobacter pylori eradication only

Herold, Johannes Helmut January 2021 (has links) (PDF)
Hintergrund: Der EGILS (European Gastro-Intestinal Lymphoma Study) Consensus Report von 2011 enthält als zentralen Therapiebaustein die H.p.-Eradikationsbehandlung mit nachfolgendem „Watch-and-Wait“ bzw. die Nachsorge nach Vollremission. Voraussetzung für eine strukturierte Nachsorge ist eine gute Patientencompliance. Eine Studie über Dauer und praktische Umsetzbarkeit der Nachsorge, insbesondere nach Vollremission, gibt es bisher nicht. Ziel: Ziel dieser retrospektiven Arbeit war es zu überprüfen, ob die von der EGILS empfohlenen Nachsorgeintervalle von den Patienten nach einer alleinigen H.p.-Eradikation eingehalten werden. Ferner sollte auf dieser Grundlage und unter Berücksichtigung des Therapieerfolgs eine Empfehlung für optimale Nachsorgeintervalle nach klinischer Vollremission erarbeitet werden. Methode: 106 Patienten (50 weiblich; 56 männlich); Alter 59 (33 – 85) Jahre mit beliebigem H.p.Status, histologisch gesichertem gastralem MALT-Lymphom und alleiniger H.p.-Eradikationsbehandlung wurden eingeschlossen. Grundlage zur Beurteilung war, bis zur Vollremission, das Nachsorgeschema gemäß EGILS (alle 4-6 Monate); danach erfolgte die Nachsorge alle 6 bis 12 Monate. Die Compliance wurde bei jedem Patienten als das Verhältnis aus erfüllter Nachsorgepflicht zu individueller Gesamtdauer der Nachsorge berechnet und über alle Patienten gemittelt. Ergebnisse: Die meisten Patienten erreichen nach alleiniger H.p.-Eradikation unabhängig vom H.p.-Status eine Vollremission (ca. 71%). Die Nachsorgen wurden über den gesamten Beobachtungszeitraum zu ca. 55% eingehalten. Patienten mit Interesse an einer Nachsorge nehmen diese über Jahre hinweg sehr zuverlässig war. In dieser Patientengruppe liegt die Compliance bei ca. 95%. Schlussfolgerung: Die exzellente Prognose gastraler MALT-Lymphome, unabhängig vom H.p.-Status, und die hohe Bereitschaft der Patienten für Nachsorgeuntersuchungen auch nach Vollremission erhöht die Attraktivität einer „Watch-and-Wait“-Strategie. Nach klinischer Vollremission sind jährliche endoskopische Nachsorgeuntersuchungen praktisch umsetzbar. / Background: The European gastrointestinal lymphoma study (EGILS) consensus report from 2011 included as a central therapy basis the H pylori eradication treatment with subsequent “watch and wait” as well as follow-up care after full remission. The main requirement for a structured follow up care is good patient compliance. A study about the duration and the practical feasibility of follow up care, especially after full remission has not been carried out to date. Aims: The aim of this retrospective work was to review whether patients were complying with the EGILS recommended follow-up intervals after a single H pylori eradication treatment. Furthermore, on this basis and in consideration of treatment success, a recommendation for the optimal follow-up interval after a full clinical remission should be developed. Methods: 106 patients (50 females, 56 males) with an average age of 59 years (33-85) with a variable H pylori status, histologically confirmed gastric MALT-lymphoma and a single H pylori eradication treatment, were included. The basis of assessment was, up to full remission, the follow-up scheme in accordance with EGILS (4-6 months) thereafter follow up in 6-12 months. The compliance for every patient was calculated as the ratio of fulfilled follow-up care obligations to individual duration of follow-up care and averaged out over all Patients. Results: The majority of patients reached a full remission after a single H pylori eradication independent of H pylori status (ca. 71%). Ca 55% of the follow-up care was adhered to the whole observation period. Patients with an interest continued to take part reliably in follow-up care for many years. The compliance in this patient group was ca 95%. Conclusion: The excellent prognosis of gastric MALT-lymphoma, independent of H pylori status and the willingness of the patients to have aftercare-check-ups even after a full remission, increases the attraction of a “watch and wait” strategy. After a full clinical remission, yearly endoscopic check-ups can be easily implemented.

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