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Metabolismo proteico e estresse oxidativo em musculatura de fetos provenientes de ratas portadoras de tumor submetidas a dieta rica em leucina / Protein metabolism and oxidative stres in fetal muscle proceeding from tumour-bearing rats fed a leucine-rich dietCruz, Bread Leandro Gomes da, 1979- 12 August 2018 (has links)
Orientador: Maria Cristina Cintra Gomes Marcondes / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-12T11:27:11Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007 / Resumo: Câncer acomete, aproximadamente, uma entre 3000 gravidezes e causa um terço de mortes maternas. A leucina é usada experimentalmente para minimizar as alterações do metabolismo protéico durante o crescimento tumoral. Este trabalho investigou os efeitos do crescimento tumoral sobre o metabolismo protéico e estresse oxidativo nos fetos provenientes de ratas alimentadas com dieta suplementada com leucina. Os grupos de fêmeas prenhes foram divididos da seguinte forma: controle (C), controle com dieta suplementada com leucina (L), tumor (W), tumor com dieta suplementada com leucina (WL), dieta pareada á ingestão diária das ratas do grupo W (Cp), dieta suplementada com leucina e pareada á ingestão diária das ratas do grupo WL (Lp). Após 20 dias de prenhes os músculos fetais foram analisados. Os resultados mostraram que a síntese protéica fetal foi reduzida no grupo W quando comparados aos outros grupos. Houve significativa recuperação da síntese protéica no músculo dos fetos WL sugerindo efeito positivo do uso de aminoácido de cadeia ramificada nessa situação. Ocorreu aumento significativo da degradação protéica nos fetos W. Essa perda protéica foi amenizada pelo uso da dieta suplementada com leucina indicando efeito benéfico sobre a degradação protéica no grupo WL que obteve valores similares ao observado no grupo C. A atividade da enzima glutationa-S-transferase ficou elevada no músculo de fetos WL em comparação com o grupo W. Também houve aumento na atividade da enzima fosfatase alcalina no grupo WL indicando maior atividade celular nesse grupo quando comparado ao grupo W. A presença de MDA (Malondialdeído) no músculo fetal também ficou reduzida nos fetos WL. Com a análise desses parâmetros conclui-se que a dieta suplementada com leucina pode alterar o metabolismo muscular fetal aumentando a síntese protéica e reduzindo o efeito danoso do estresse oxidativo. / Abstract: Cancer occurs in approximately 1 per 3.000 pregnancies and accounts for one-third of maternal deaths. Leucine has been used experimentally to minimize the protein metabolism changes during tumor growth. The present work investigated the effects of tumor growth on muscle protein metabolism and oxidative stress in fetus pregnant rats fed a leucine-rich diet. Fetal groups from pregnant Wistar rats were: control (C), control fed leucine-rich diet (L), tumor-bearing (W), tumor-bearing fed leucine-rich diet (WL), Pair-fed control (P) and Pair-fed Leucine (PL). After 20 days the fetal muscles were analyzed. The results showed that fetal protein synthesis was decreased in W group, when compared to the other groups. The significantly recover on muscle protein synthesis in fetus of WL group suggested a positive effect of this branched-chain amino acid. There was a significant increase on protein degradation in W fetus and a protective effect of the leucine-rich diet on muscle protein waste in WL group, since it was similar to C group. The muscle enzyme glutathione-S-transferase activity was increased in WL fetus in comparison to W group. The muscle alkaline phosphatase activity increased in WL group. The malondialdehyde content (MDA) in fetal muscle was decreased in WL fetus. The leucine supplemented diet can alter the fetal muscle protein metabolism, improving the fetal muscle protein synthesis and reducing the oxidative stress. / Mestrado / Fisiologia / Mestre em Biologia Funcional e Molecular
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Avaliação morfofuncional do desenvolvimento da articulação do joelho em fetos humanos / Morphofunctional evaluation of the knee joint development in human fetusesJosy Alvarenga Cal Rosa 12 March 2015 (has links)
A articulação do joelho tem sido vastamente estudada nas ultimas décadas. Este intenso interesse pode ser visto sob o foco da complexidade desta articulação e de sua importância clínica. No entanto, nota-se escassa informação a respeito de aspectos morfológicos e ultraestruturais sobre o desenvolvimento desta articulação, em fetos humanos de diferentes faixas etárias, o que poderia servir de base teórica para estratégias de reparo da cartilagem e engenharia de tecidos, bem como contribuir para uma melhor compreensão de doenças e malformações ao longo do desenvolvimento dos componentes articulares. Desse modo, considerando-se a importância do conhecimento sobre aspectos morfofuncionais do desenvolvimento normal dos tecidos cartilagíneos na articulação do joelho humano, realizou-se a presente pesquisa com fetos humanos abrangendo a faixa etária da 16ª a 31ª semanas de vida intrauterina. Foram utilizados 20 fetos, os quais foram divididos em 4 grupos (n=5) da seguinte forma: grupo 1 (G1): 16-19 semanas de vida intrauterina (VIU); grupo 2 (G2): 20-23 semanas VIU; grupo 3 (G3): 24-27 semanas VIU e grupo 4 (G4): 28-31 semanas VIU, em que foram realizadas análises morfométricas da cartilagem das epífises do fêmur e tíbia na articulação do joelho, para os parâmetros: área dos condrócitos, densidade de condrócitos e matriz extracelular, análise estereológica para o volume dos condrócitos, e análise qualitativa da distribuição, organização e tipificação de fibras colágenas com uso de Picro-sirius sob análise com luz polarizada. Também se analisou a ultraestrutura através de microscopia eletrônica de varredura (MEV). Frente à metodologia proposta e os resultados obtidos a respeito da avaliação morfofuncional, concluiu-se que a área e o volume dos condrócitos, bem como a densidade da matriz extracelular, na região média das epífises cartilagíneas, tanto do fêmur quanto da tíbia, aumentaram com o avançar da faixa etária, enquanto a densidade dos condrócitos diminuiu. Na região média das epífises, a cartilagem imatura dos fetos mais jovens, inicialmente com características de uma zona de proliferação, passa a apresentar, em fetos com idade mais avançada, características de uma zona de maturação, com condrócitos maiores e mais distantes uns dos outros. Na camada superficial da epífise a organização e orientação das fibras de colágeno modificam-se nos diferentes grupos, passando de uma orientação irregular no grupo dos fetos mais jovens, para uma organização pantográfica no grupo de fetos mais desenvolvidos. Finalmente, verifica-se a clara relação entre o amadurecimento da cartilagem e as alterações na organização e orientação das fibras colágenas, as quais contribuem para as propriedades requeridas na cartilagem em cada fase de seu desenvolvimento, tais como resistência à tensão, resistência à compressão e habilidade para distribuir cargas / The knee joint has been widely studied in recent decades. This intense interest can be seen from the perspective of the joint complexity and its clinical importance. However, there is little information about morphological and ultrastructural aspects of the development of this joint, particularly in human fetuses within different age, which could serve as a theoretical basis for cartilage repair strategies and tissue engineering, as well as contributing for a better understanding of diseases and malformation during the development of joint components. Thus, considering the importance of morphological and functional aspects of normal cartilaginous tissue development in the human knee joint, this research was performed with human fetuses covering the age range 16 to 31 weeks of intrauterine life. Twenty (20) fetuses were divided into 4 groups (n = 5) as follows: Group 1 (G1): 16-19 weeks, Group 2 (G2): 20-23 weeks, Group 3 (G3): 24-27 weeks and Group 4 (G4): 28-31 weeks. For the femoral and tibial epiphysis cartilage in the knee joint, it was performed morphometric analysis regarding area of chondrocytes, percent density of chondrocytes and extracellular matrix, stereological analysis of the chondrocytes volume and qualitative analysis of the distribution, organization and characterization of collagen fibers using picrosirius staining under analysis with polarized light. It was also analyzed the ultrastructure by scanning electron microscopy. Facing the proposed methodology and the results regarding the morphological evaluation of the middle region of both femur and tibia epiphysis, it was concluded that the area and the volume of the chondrocytes, as well as the density of extracellular matrix increased with advancing age, while the percent density of chondrocytes decreased. In the middle region of the epiphysis, immature cartilage of younger fetuses, initially with characteristics of a proliferation zone starts to present, in older fetuses, characteristics of maturation zone, presenting larger chondrocytes and more distant from each other. In the epiphysis cartilage surface, the organization and orientation of the collagen fibers changed in different groups, from an irregular orientation in the younger fetuses group, to a pantograph organization in the most developed fetuses group. Finally, it was observed the relationship between the cartilage development and the changes in the collagen fibers organization and orientation in order to obtain the cartilage properties required at each stage of the development, such as tensile strength, resistance to compression and ability to distribute loads
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Fetal and placental haemodynamic responses to hypoxaemia, maternal hypotension and vasopressor therapy in a chronic sheep modelErkinaro, T. (Tiina) 22 August 2006 (has links)
Abstract
Knowledge of the effects of maternally administered vasopressors on human fetal and placental haemodynamics is sparse and limited to elective Caesarean deliveries in uncomplicated pregnancies. We hypothesized that, after short-term fetal hypoxaemia, which activates fetal cardiovascular compensatory mechanisms, treatment of maternal hypotension with ephedrine or phenylephrine results in divergent responses in fetal and placental haemodynamics.
Chronically instrumented near-term sheep fetuses with either normal placental function or increased placental vascular resistance following placental embolization were exposed to two subsequent periods of decreased fetal oxygenation caused by maternal hypoxaemia and epidural-induced hypotension. The fetuses that underwent placental embolization were also chronically hypoxaemic.
Fetal and placental haemodynamics were assessed by invasive techniques and by noninvasive Doppler ultrasonography. Our results show that umbilical artery blood flow velocity waveforms cannot be used to derive information of fetal cardiac function. Furthermore, the changes in placental volume blood flows and vascular resistances caused by maternal vasopressor treatment cannot be reliably recognized based on uterine and umbilical artery pulsatility index values.
In response to acute hypoxaemia, a fetus with normal placental function redistributes its right ventricular cardiac output from the pulmonary to the systemic circulation and is able to increase its combined cardiac output, with a concomitant relative decrease in the net forward flow through the aortic isthmus. However, fetal haemodynamic responses to subsequent hypoxaemic insults may vary. Furthermore, the compensatory responses of fetuses with increased placental vascular resistance differ from those of normal fetuses. In these fetuses, repeated episodes of a further decrease in oxygenation lead to lactataemia.
The effects of ephedrine on uteroplacental and umbilicoplacental circulations were more favourable than those of phenylephrine. Ephedrine restored the changes in fetal cardiovascular haemodynamics caused by maternal hypotension to the baseline conditions in both embolized and nonembolized fetuses. Phenylephrine did not reverse fetal pulmonary vasoconstriction or the relative decrease in the net forward flow through the aortic isthmus. Moreover, fetal left ventricular function was impaired by phenylephrine. Although no significant differences in fetal acid-base status were observed in fetuses with normal placental function, the lactate concentrations of the embolized fetuses increased further when maternal hypotension was treated with phenylephrine.
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Evaluation of the Genetic Differences Between Two Subtypes of Campylobacter fetus (Fetus and Venerealis) in CanadaMukhtar, Lenah January 2013 (has links)
The pathogen Campylobacter fetus (CF) is classified into two subspecies, Campylobacter fetus subspecies fetus (CFF) and Campylobacter fetus subspecies venerealis (CFV). Even though CFF and CFV are genetically closely related, they exhibit differences in their host adaptation; CFF inhabits the gastrointestinal tract of both humans and several animal species, while classical CFV is specific to the bovine genital tract and is of particular concern with respect to international bovine trade regulation. Traditionally, differentiation between the two subspecies has been achieved using a limited number of biochemical tests but more rapid and definitive genetic methods of discrimination are desired. A recent study suggested that the presence of a genomic island only in CFV could discriminate between the two sub- species but this hypothesis could not be confirmed on a collection of isolates originating in Canada.
To identify alternative gene targets that would support accurate subspecies discrimination, this study has applied several approaches including suppression subtractive hybridization and whole genome sequencing supplemented with optical mapping. A subtractive hybridization screen, using a well-characterized CFV isolate recovered during routine screening of bulls in an Artificial Insemination center in western Canada and that lacked much of the genomic island and a typical Canadian CFF isolate, yielded 50 clones; characterization of these clones by hybridization screening against selected CF isolates and by nucleotide sequence BLAST analysis identified three potentially CFV-specific clones that contained inserts originating from a second genomic island. Further screening using a larger CF sample set found that only Clone #35 was truly CFV-specific. Optical maps (NcoI digest) of the Canadian CFF and CFV isolates used for the subtractive hybridization showed that certain regions of these genomes were quite distinct from those of two reference strains. Whole genome sequencing of these two isolates identified two target genes (PICFV5_ORF548 and CFF_Feature #3) that appear to be selectively retained in the two subspecies. Screening of a collection of CF isolates by PCRs targeting these three loci (SSH_Clone #35, PICFV5_ORF548 and CFF_Feature #3) supported their use for subspecies discrimination. This work demonstrates the complex genomic diversity associated with these CF subtypes and the challenge posed by their discrimination using limited genetic loci.
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Vliv kouření matky na homeostázu fetoplacentární jednotky / The effect of maternal smoking on the homeostasis of the fetoplacental unitAdamcová, Karolína January 2021 (has links)
Maternal smoking causes serious health danger for a mother but especially for a baby. Cigarette smoking produces complex steroidogenesis changes during the whole life of a woman. To study the influence of smoking on fetoplacental unit focusing on steroid hormons it was important first to concentrate on changes of the chosen steroids around the delivery. The first part of the thesis is dedicated to observe some chosen steroid hormons in peripartal period (37th week of the pregnancy, first stage of labor of mothers and mixed umbilical blood of their neonates) and to look for relations to the age of mother, the increase of the weight during the pregnancy, the type of the delivery and the sex of the baby. It was interesting to compare steroids in the relation to the type of the delivery: vaginal delivery versus planned caesarean section. Non-smoking women who delivered a boy spontaneously had significantly higher level of 17-OH-pregnenolone, progesterone, cortisol, corticosterone and significantly lower level of estradiol in comparison with non-smoking women who delivered a boy by a planned Caesarean section. In the maternal blood in the 37th week of the pregnancy there were found differences between steroids in accordance to the sex of the fetus but they were not found in the neonates' case. The age...
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A semiquantitative and qualitative histopathologic assessment of the effect of type II intrauterine growth retardation on the structure of the carotid bodies in fetuses and neonatesLaing, David 24 August 2017 (has links)
The major physiological function of the carotid body is to respond to a low partial pressure of oxygen in the systemic arterial blood. The structure and functions of the adult carotid body have been extensively investigated over the past fifteen years. However, the carotid body in children has been relatively neglected with only a handful of studies being performed. To date, no study has been undertaken to investigate the effects of intrauterine hypoxia on the carotid body of foetuses. Clinically, intrauterine growth retardation has been ascribed, amongst other causes, to placental insufficiency that results in chronic hypoxia in the fetus. Intrauterine growth retardation can be divided into two types: - Type I (symmetrical) and type II (asymmetrical). In Type II intrauterine growth retardation, growth retardation does not become clinically evident until the third trimester. There is relative brain sparing with a greater deprivation in the size of abdominal organs, such as the liver and the kidneys. Previous studies have shown that there is no correlation between volume of the carotid body and hypoxia in children. However, Heath et al. made the observation that there are three variants of chief cells (progenitor, light and dark) within the carotid body and that an increase in the relative percentage of the dark subtype is an indicator of hypoxia. Using this observation, the present study set out to test two hypotheses: Firstly, whether the carotid body is functional in utero; and secondly whether there are any objective morphological changes in the carotid bodies of fetuses that have been subjected to intrauterine growth retardation. The carotid bodies from 72 fetuses with a gestational age between thirty and forty weeks were removed from the archived autopsy material, and differential cell counts were performed of the various cells present within the carotid bodies, using haematoxylin and eosin stained sections of the carotid bodies. The cases were assigned to three groups: - I) cases that had clinical and pathological evidence of intrauterine growth retardation, 2) negative controls and 3) positive controls. The three main groups were categorised as follows: -: (1) Intrauterine growth retardation (all cases with a weight for gestational age that is below the tenth centile and a brain to liver ratio of greater than four.) (2) Negative controls (all cases in whom there is a normal weight for age, a brain to liver ratio of less than three and no histological evidence of an episode of significant hypoxia before death). (3) Positive controls (all cases in whom there was clinically significant hypoxia present before death). The groups comprised of: 20 hypoxic positive controls, 15 negative controls, and 16 test cases which had suffered from intrauterine growth retardation. The remaining 21 cases were 7 dysmorphic infants, 3 congenital infection cases (congenital syphilis) and 11 cases that fitted the negative control criteria but had suffered significant hypoxia, thus excluding them from that category. The results showed that no significant difference was present in the percentage of sustentacular cells between any of the three groups. The results of the percentage of dark chief cells were as follows: l) mean percentage of dark chief cells in the intrauterine growth retardation group was 21.1 ±10.9%. 2) mean percentage of dark chief cells in the negative controls was 12.3 ±7.3%. 3) mean percentage of dark chief cells in the positive controls was 21.2 ±9.8%. A significant difference was present between the intrauterine growth retardation cases and the negative controls p=0.013, and between the positive and negative controls p=0.006. The dark chief cell count in the intrauterine growth retardation group showed no significant difference from the positive controls. No age-related difference appeared to be present in any of the groups. The conclusions reached are: a) Clinical hypoxia correlates with morphological changes in the carotid body, manifesting as an increase in the percentage of dark chief cells. b) intrauterine growth retardation cases show similar morphological changes in the carotid body to cases that have suffered from clinical hypoxia. c) therefore, by deduction intrauterine growth retardation fetuses have probably also been exposed to significant hypoxia while in utero. d) the fact that morphological changes in response to hypoxia are occurring in the carotid bodies of fetuses is an indication that the carotid body may be functional in utero. The results of the study indicate that a dark chief cell percentage of greater than 20% indicates that the fetus has been subjected to significant hypoxia, while a percentage of less than 10% indicates that it has not. A percentage of between 10 and 20% is unhelpful in determining whether hypoxia has taken place. The results of this study indicate that histological examination of the carotid bodies in neonates suspected of intrauterine growth retardation could be a useful additional means of assessment.
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Detection of Campylobacter fetus in bovine preputial scrapings using PCR and culture assaysSchmidt, Tracy 13 May 2009 (has links)
The traditional method for the diagnosis of bovine genital campylobacteriosis is the culture and identification of the causative organism, Campylobacter fetus subsp. venerealis (Cfv) from the genital tract. This approach is considered relatively insensitive due to the fragility of the bacteria, their specific nutritional and atmospheric requirements and their being easily overgrown by commensal bacteria. The identification of isolates is also problematic due to the limited biochemical activity of the bacteria. With the rapid advances made in the molecular field, assays have become more robust and cost-effective making them feasible for the diagnostic laboratory. The potential speed, sensitivity and specificity offered by these assays provide attractive alternatives for the identification of pathogens which are notoriously difficult to identify. The first part of this investigation was concerned with the implementation and evaluation of a polymerase chain reaction (PCR) assay for the direct detection of C. fetus in bovine preputial specimens. The specificity of a published C. fetus-specific primer pair was established by testing C. fetus reference and field isolates in addition to a collection of other Campylobacter species and organisms which may encountered in the genital tract of cattle. All C. fetus isolates tested yielded a single PCR amplicon of approximately 750 bp. No amplicons were generated when any of the other non-C. fetus isolates were tested. Following minor modifications to the assay, the sensitivity of the assay was determined using spiked Weybridge medium. A detection limit of 615 Cfv/mR Weybridge medium (or 6,15 cell equivalents per PCR assay) was obtained. Preputial material collected and submitted for laboratory testing may often be contaminated with faeces, urine, semen and/or blood. All of these components are known to be potential PCR inhibitors and the influence of each, on the sensitivity of the PCR assay, was subsequently evaluated. Faeces were identified as a potent inhibitor and contamination of specimens with as little as 1% (w/v) faeces reduced the sensitivity of the assay. Concentrations of up to 50% (v/v) of blood, urine and semen had no effect on the sensitivity of the assay. Preputial specimens, collected in Weybridge medium, were subsequently pooled and spiked and used to establish the sensitivity of both the PCR and culture methods as well as determine the influence of time on the sensitivity of the assays. Testing was carried out in triplicate on samples collected from different herds which were ascertained to be free of Cfv based on the use of specific selection criteria. The detection limit of the culture method was found to be better than that achieved using PCR only immediately after the samples were spiked. The detection limit of the culture method decreased with time whilst the detection limit of the PCR assay remain unchanged up to 72 hours post-inoculation. Ensuing field evaluation involved the testing of 212 clinical samples using both the culture method and the optimized PCR assay. Of the samples tested 4,2% were found to be positive using the PCR assay, whilst only 3,8% were found to be positive by culture. Based upon this evaluation the analytical specificity of the PCR assay was calculated to be 99% and the analytical sensitivity, 85,7%. The second part of this investigation was concerned with the subspeciation of C. fetus isolates. Currently the only test recommended by the Office International des Epizooties (OIE) for the subspeciation of isolates, is tolerance to 1% glycine. Doubts over the reliability of this test have led to alternative or supplementary tests being sought. Within the context of this investigation a collection of 40 South African field isolates were subspeciated using a previously described subspecies-specific primer set as well as the traditional 1% glycine tolerance phenotyping test. Additionally, other phenotyping tests (selenite reduction, growth at 42 °C and susceptibility to metronidazole and cefoperazone) were evaluated to determine their suitability for use as an aid in the subspeciation of C. fetus isolates. None of the field isolates yielded a Cfv-specific subspecies PCR amplicon using the published primer set suggesting that all of the isolates were Campylobacter fetus subsp. fetus (Cff). Based on tolerance to 1% glycine however, only 6 isolates were identified as Cff (glycine tolerant), whilst the remainder were classified as Cfv. The results of the ‘sensitive’ hydrogen sulphide test indicated that the Cfv isolates were specifically Cfv biovar intermedius. The lack of agreement between the PCR and the phenotyping subspeciation results concur with the findings reported by other researchers. It is consequently concluded that the published VenSF/VenSR subspecies-primer set is unsuitable for the subspeciation of South African field isolates. / Dissertation (MSc)--University of Pretoria, 2008. / Veterinary Tropical Diseases / unrestricted
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Untersuchungen zu Nachweis und Differenzierung von Campylobacter fetus subsp. venerealis beim Rind mit konventionellen und molekularbiologischen MethodenBagon, Audrey 09 November 2006 (has links)
Campylobacter fetus subsp. venerealis ist der Erreger der bovinen genitalen Campylobacteriose, einer anzeigepflichtigen Tierseuche. Er hat sein natürliches Reservoir im Präputialsack klinisch gesunder Bullen und ist in der Lage, Aborte zu verursachen (enzooti-scher Abort). Davon abzutrennen sind Infektionen mit C. fetus subsp. fetus, welcher natürlicherweise im Intestinaltrakt des Rindes auftritt und ebenfalls Aborte auszulösen vermag (spo-radischer Abort). Während C. fetus subsp. venerealis einen ausgeprägten Tropismus für die Genitalschleimhaut des Rindes aufweist, handelt es sich bei der Subspezies fetus um einen Zoonoseerreger, der beim Menschen schwerwiegende Erkrankungen mit zumeist septikämischen Charakter verursachen kann. Die Übertragung von C. fetus subsp. venerealis erfolgt hauptsächlich durch den natürlichen Deckakt, es besteht aber auch die Gefahr der Verbreitung durch künstliche Besamung, da klinisch gesunde Bullen den Erreger im Samen enthalten können. Die Unterschiede in der Epidemiologie und die klinische Bedeutung der beiden C. fetus-Subspezies erfordern eine exakte Identifizierung und Differenzierung. Der erste Teil der Untersuchung befasst sich daher mit den Möglichkeiten des molekularen Erregernachweises. Im zweiten Teil wurden 50 Isolate aus den vergangenen fünf Jahren mit molekularen Methoden auf ihre genetische Ähnlichkeit untersucht. Eine Abgrenzung durch traditionelle mikrobiologische Methoden ist sehr problematisch, da sie im Wesentlichen auf nur zwei Reaktionen beruht: die Glycin-Toleranz und die Na-Selenit-Reduktion, wobei neueste Untersuchungen unter standardisierten Bedingungen nur die Glycin-Toleranz als eindeutig charakterische Reaktion für beide Subspezies übrigließe. Aus diesem Grunde wurden PCR-Untersuchungen zur Identifizierung und Differenzierung beider C. fetus-Subspezies eingeführt. In einem ersten Schritt wurde Campylobacter fetus spezifisch nachgewiesen. Danach erfolgte die Differenzierung der Subspezie durch eine weitere PCR, in der nur bei Vorliegen der DNS von C. fetus subsp. venerealis ein Amplikon erhalten wurde. Insgesamt wurden 103 C. fetus-Isolate untersucht, einschließlich der Typenstämme von C. fetus subsp. fetus und C. fetus subsp. venerealis. Auf Grund der Ergebnisse des Gly-cintoleranztests konnten 81 C. fetus subsp. venerealis (Glycin intolerant) und 22 C. fetus subsp. fetus (Glycin tolerant) identifiziert werden. Die Ergebnisse des Glycintoleranztests und der PCR stimmten bei allen 103 C. fetus Isolaten überein. Versuche zum Direktnachweis von C. fetus subsp. venerealis aus Bullensperma durch Anwendung von fünf unterschiedlichen DNS-Extraktionsmethoden waren in ihren Ergebnissen hinsichtlich ihrer Sensitivität nicht zufrieden stellend (104 KbE/ml). Daraus ergibt sich zwingend, dass die Kultivierung des Erregers vor seiner phäno- und genotypischen Charakterisierung weiterhin unverzichtbar bleibt. Durch Untersuchungen mittels PFGE wurde gezeigt, dass die Campylobacter fetus subsp. venerealis-Population, die in Deutschland vorkommt, genetisch nicht einheitlich ist. Eine strenge Gruppierung nach geografischen Regionen war nicht möglich. Innerhalb größerer Gruppen genetisch ähnlicher Stämme fielen Isolate mit identischen Mustern auf, was auf gemeinsame Infektionsquellen hindeutet. Die ERIC-PCR sollte in der vorliegenden Arbeit als zweite Methode der Analyse des Gesamtgenoms zur weiteren Stützung der Ergebnisse der Makrorestriktionsanalyse beitragen. Die Analysen mittels ERIC-PCR machte ein hohes Maß an Heterogenität innerhalb der einzelnen Spezies sichtbar, lässt jedoch keine Assoziation zwischen Bandenprofilen und einer Zuordnung zum Krankheitsbild oder zur geographischen Herkunft zu.
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Testing women as mothers : the policy and practice of prenatal HIV testingLeonard, Lynne January 2003 (has links)
No description available.
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Raman and near infrared spectroscopic analysis of amniotic fluid : metabolomics of maternal and fetal health indicatorsPower, Kristin Marie. January 2007 (has links)
No description available.
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