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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.
131

Avaliação histologica e imunohistoquimica da maturidade dos plexos mioentericos na gastrosquise experimental de ratos realizada em duas diferentes idades gestacionais / Histologic and immunohistochemical evaluation of the myenteric plexus maturity in the intestines of the experimental rat gastrochisis in two different gestational days

França, Willy Marcus Gomes 24 November 2006 (has links)
Orientador: Lourenço Sbragia Neto / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-08T14:55:03Z (GMT). No. of bitstreams: 1 Franca_WillyMarcusGomes_D.pdf: 3673624 bytes, checksum: 691804a882449e544abe2d0c2ae420af (MD5) Previous issue date: 2006 / Resumo: Na gastrosquise (G), o grau de lesão das alças intestinais exteriorizadas está diretamente relacionado ao tempo de contato com o líquido amniótico (LA) e exposição ao mecônio, que causam alterações morfológicas e histológicas do intestino, além da formação de uma fina camada de fibrina (fibrous peel) sobre a serosa, formando aderências entre as alças intestinais. Estas lesões levam ao hipoperistaltismo intestinal e deficiência na absorção dos nutrientes, contribuindo para o aumento da morbidade e alto custo médico-hospitalar. O hipoperistatismo na G é atribuído à desorganização e à imaturidade dos plexos mioentéricos. Estas características podem servir como marcadores do grau de lesão intestinal, e que podem ser identificados pela presença de neurofilamentos dos plexos nervosos intestinais e sugerir a antecipação do parto. Nesse estudo identificamos as alterações morfológicas e histológicas intestinais e dos plexos mioentéricos em dois diferentes tempos de contato com o LA. A G experimental em fetos de ratas Spreague-Dowley foi realizada em duas idades gestacionais, 18,5o dia (E18,5) e 19,5o dia (E19,5), que foram divididos em 3 subgrupos: controle (C), sham (S) e gastrosquise (G). Medimos o peso corporal fetal (PC), peso (PI) e comprimento intestinais (CI). As camadas da parede intestinal e os plexos mioentéricos foram avaliados pela coloração de H&E e imunofluorescência (?-Internexina), respectivamente. O PC não apresentou diferença significativa entre C/S/G, nos 2 grupos. O PI e CI foram respectivamente maior e menor nos fetos G (p<0,001) nos 2 grupos. Os diâmetros intestinais e as camadas da parede apresentaram diferença significativa entre C/S/G, em ambos os grupos (p<0,001), mas o tempo de contato com LA e exposição ao mecônio comprometeram a serosa e D-II (diâmetro II) (p<0,001), e CI (p=0,001). A ?-internexina apresentou imunorreatividade mais intensa nos fetos G de E18,5. Concluímos que no modelo de G em fetos de ratos, as alterações da parede intestinal, principalmente da camada serosa e do comprimento intestinal, bem como a imaturidade dos plexos mioentéricos, apresentaram-se mais intensas nos fetos cujo contato com o LA e exposição ao mecônio foram mais prolongados (G/E18,5). Estudos experimentais adicionais devem ser desenvolvidos e direcionados para compreensão da motilidade intestinal na G com o objetivo de minimizar os danos neuromusculares nas alças intestinais expostas ao LA e permitir avaliar as supostas vantagens da antecipação do parto para fetos humanos com G / Abstract: BACKGROUND: The amniotic fluid (AF) and its components such as fetal urine and meconium may lead to intestinal alterations in gastroschisis (G), which cause immaturity of the myenteric plexus and consequent intestinal hypomotility and malabsorption. In this study we identified morphological and histological alterations of the intestine and of the myenteric plexus with two different times of exposure to the AF. METHODS: The experimental G was achieved at two different gestational ages, on day 18.5 (E18.5) and on day 19.5 (E19.5) of gestation in fetal rats which were divided into 3 subgroups: control (C), sham (S) e gastroschisis (G). We measured fetal body weight (BW), intestinal weight (IW) and intestinal length (IL). The layers of intestinal wall and myenteric plexus were evaluated by hematoxylin and eosin staining (H&E staining) and immunofluorescence (?-Internexin), respectively. RESULTS: BW did not show significant differences among C/S/G, in both groups. IW and IL were respectively larger and shorter in the G fetuses (p<0.001) in both groups. Intestinal diameters and wall layers presented significant differences among C/S/G in both groups (p<0.001), but time of exposure to AF compromised the serous membrane, D-II (diameter II) (p<0.001) and IL (p=0.001). The ?-Internexin presented more intensive immunoreactivity in G/E18.5 fetuses. CONCLUSION: In gastroschisis, the longer the time of exposure to AF, the more severe will be bowel impairment, especially concerning IL and the serous layer; and the more immature will be the myenteric plexus / Doutorado / Cirurgia / Doutor em Cirurgia
132

Activation of TLR5 by Salmonella-derived flagellins

Metcalfe, Hannah Jane January 2012 (has links)
No description available.
133

Studies on the chemical constituents of the seeds of Clausena lansium and their anti-obesity activity

Huang, Li January 2017 (has links)
University of Macau / Institute of Chinese Medical Sciences
134

The uptake of drugs in relation to their action on tissues

Rang, H. P. January 1964 (has links)
No description available.
135

Epidemiological and aetiological aspects of diarrhoeal disease in the Eastern Cape

Baxter, Esther January 1993 (has links)
Diarrhoeal disease is a major cause of mortality in children in developing countries. It also remains a serious problem among all age groups throughout the world. Whereas studies to determine the epidemiological and aetiological factors of diarrhoeal disease have been reported for other parts of South Africa and the world, as yet no information is available for the Eastern Cape. Therefore this study was undertaken to determine the factors for this area. Enteropathogens were compared for the different ages in the various population groups and, where possible, seasonal and geographical differences were emphasised. A total of 7 278 faecal samples were examined by six laboratories in the Eastern Cape during the period November 1988 to October 1990. Data was recorded noting the age, sex and population group of the patients. The towns selected were Port Elizabeth, Uitenhage, Cradock, Grahamstown and their surrounding areas. The isolation rates for the pathogens studied in the various population groups were compared to those reported in similar studies in other countries. The seasonal incidences of the various selected pathogens were compared with those reported from elsewhere in South Africa. It was thought that the higher temperature of summer may influence the finding in the White population group, while rainfall would play a greater role for the Coloured and Black populations. The geographical distribution of the pathogens emphasised the difference in living conditions between the different population groups. For example a generally higher infestation rate of Helminths occurred in rural areas and in the groups living under poorer conditions. The low isolation rates for certain bacteria and the large percentage of samples from which no pathogens were isolated indicate the need for further research. However, the finding should be valuable for determining Public Health priorities and in the management of outbreaks of diarrhoeal disease.
136

The Effect of inflammatory bowel disease and growth retardation on the self-image of adolescents

Marshall, Helga Adda January 1987 (has links)
This study was undertaken to determine the effect of inflammatory bowel disease (IBD), in general, and one of its manifestations, growth retardation, in particular, on the self-image of adolescents. The conceptualization of adolescent self-image as described by D. Offer (1981) was the basis for the study's framework. The psychological, social, sexual, familial and coping selves, further classified into 11 separate content areas, comprised the adolescent self-image. A descriptive-comparative design was used to describe the self-image of adolescents with IBD and to compare the similarities and differences in self-image among the IBD adolescents with and without growth retardation and their healthy peers. A convenience sampling method was used to obtain 24 IBD subjects between the ages of 12 and 20, eleven of whom had growth retardation. A normative sample of adolescents (N = 1385) was used by permission of D. Offer for purposes of comparison with the IBD subjects. Data were gathered using the Offer Self-image Questionnaire for adolescents. The adolescents with IBD did not differ remarkably from the norm in their perceptions of self although a tendency among the females to have concerns about their body image and sexual maturation was demonstrated. The IBD subgroup without growth retardation reported self-image perceptions that were superior to the norm and the growth retarded subgroup in almost every category. The IBD subgroup with growth retardation reported a disturbed self-image in a number of areas. The males revealed disturbances primarily in body image and secondarily in emotional harmony, and adaptability to stress in the immediate environment, family relations, and sexual maturation. The females revealed self-image disturbances in sexual maturation and body image. The findings of the study suggest that growth retardation in the IBD adolescent may have a negative effect on self-image. The findings may demonstrate a more notable and broader effect of growth retardation on self-image in the males with IBD than in the females. / Applied Science, Faculty of / Nursing, School of / Graduate
137

The biochemical and antibiogram characteristics of Escherichia coli isolated from the intestine of the pigeon, Columba livia

Salameh, Bassam Michel 01 January 1991 (has links)
This study deals with the nature and characteristics of the Gram negative bacterial flora of the intestine of the domestic pigeon. Columba livia was selected for this study because of the abundance of this species around the Classroom building on the University of the Pacific campus.
138

Physiological Effects of Ascaris Suum Intestinal Microflora on 5-Hydroxytryptamine Level and Binding Sites in the Intestinal Epithelial Cells

Shahkolahi, Akbar Mohammadpour 12 1900 (has links)
Serotonin (5-hydroxytryptamine, 5-HT) has been shown to activate carbohydrate metabolism in adult female Ascaris suum. Serotonin may be either absorbed directly from the environment or synthesized de novo from the absorbed L-tryptophan in adult female A. suum. The enzymes necessary for the synthesis of 5-HT have been identified in both intestine and muscle tissues. The serotonin absorbed from the environment is obtained either from the host's gastrointestinal contents or from the 5-HT producing bacteria in the intestine of A. suum. Numerous 5-HT producing bacteria were identified in the intestinal microflora. The physiological contributions of 5-HT producing bacteria to the 5-HT level, turnover and binding sites in the intestinal tissue of A. suum were investigated.
139

Causes of neurological disorders : associations of pm2.5 exposure and intestinal disorders

Fu, Pengfei 02 July 2020 (has links)
Objective: The aims of this project were to (a) perform a systematic review and meta-analysis of the associations between multiple neurological disorders (or neurological diseases) and potential influencing factors, including the association between fine particulate matter (PM 2.5) and intestinal dysfunction, and (b) investigate the mechanisms and toxicological effects of PM 2.5 exposure in the brain and intestines using a mouse model of Alzheimer's disease (AD). Design: A systematic review and meta-analysis was conducted to assess the risks of PM 2.5 exposure, as manifested by the incidence of exposure-associate neurological disorders or intestinal dysfunction. An APP/PS1 transgenic mouse model for AD was used to study the brain damage resulting from PM 2.5 exposure, and the miRNA/mRNA regulatory mechanisms contributing to this damage. The inflammatory injuries and bacterial community changes in the intestines of AD mice exposed to PM 2.5 were also investigated. Data sources: Articles for systematic review and meta-analysis were obtained by searching PubMed and China National Knowledge Infrastructure (CNKI), which were published for more than ten years. Animal experiments were conducted at Shanxi University of Taiyuan in China, and toxicological tests were performed according to the stipulated methods and protocols. Review and experimental methods: Data on the risks of incidence of neurological disorders associated with the environmental factor (PM 2.5) and biological factors (intestinal disorders and bacteria) were obtained, and random- or fixed-effects models (depending on the I 2 value) were used to pool the odds ratios (OR) with the 95% confidence intervals (CI) from individual studies. In the animal experiments, mice were divided into four groups of five animals per group, as follows: normal control mice in filtered air, AD mice in filtered air, normal control mice in PM 2.5 air, and AD mice in PM 2.5 air. PM 2.5 mice were exposed to ambient PM 2.5 in a whole-body inhalation exposure device for 8 weeks in Taiyuan, China. Well-established methods were used to explore the toxicological mechanisms by which PM 2.5 exacerbated brain damage in AD mice, namely open-field testing, enzyme-linked immunosorbent assay (ELISA), real-time quantitative RT-PCR, hematoxylin-eosin (HE) staining, and transmission electron microscopy (TEM). Brain damage and related biomarkers in the brains were measured, and miRNA and mRNA profiles were detected using high-throughput sequencing methods. The signaling pathways of miRNAs or mRNAs were predicted and summarized, and specific miRNAs and mRNAs were screened to explore the possible regulatory mechanisms of PM 2.5 -induced brain damage in AD mice. Intestinal and fecal samples from these mice were also subjected to 16S rRNA gene sequencing. HE staining, ELISA, and metagenome bacterial diversity analyses were performed to investigate the effects of PM 2.5 inhalation on intestinal tissue damage, inflammatory responses, and changes of bacterial diversity and communities in AD mice. Results: Long-term PM 2.5 exposure has been associated with increased risks of stroke, dementia, AD, autism spectrum disorder (ASD), and Parkinson's disease (PD) in humans, with the risks of ischemic and hemorrhagic stroke being higher than that of stroke in general. Furthermore, a relatively higher risk of stroke has been observed in heavily polluted countries compared to less polluted countries. It is known that some intestinal disorders and related problems such as constipation, inflammatory bowel disease, irritable bowel syndrome, small intestinal bacterial overgrowth, and diarrhea significantly increase the risks of developing AD or PD. For example, the risk estimates of Helicobacter pylori infection were significantly associated with AD and PD. From another angle, preliminary animal experimental results showed that PM 2.5 promoted brain morphological damage and decreased spatial exploration ability in AD mice, and was concomitant with increases in the concentrations of amyloid-β-42, acetylcholinesterase, tumor necrosis factor-α, and interleukin-6 and decreases in the concentrations of choline acetyltransferase. High-throughput sequencing and bioinformatics analyses revealed that miRNAs and mRNA had differential expression profiles subsequent to PM 2.5 exposure, which suggested that these species are involved in the molecular regulatory mechanisms and possible signal pathways of PM 2.5 -aggravated brain injury in AD mice. These PM 2.5 -aggravated brain injuries were correlated with pathological intestinal injury, inflammatory responses, and changes in bacterial diversity in the intestines and feces of PM 2.5 -exposed AD mice, and decreases in predominant bacteria were identified. These data will assist in delineating the ability of PM 2.5 exposure to induce pathological changes in the brain and gut tissue via the brain-gut axis and thereby aggravate AD. Conclusions: A systematic review and meta-analysis showed that there is a significant association between PM 2.5 exposure and the occurrence of stroke, dementia, AD, ASD, and PD, and a strong association between intestinal disorders and the presence of certain bacteria and the development of AD and PD. PM 2.5 (environmental factors) and intestinal disorders accompanied by changes in bacterial diversity (internal biological factors) appeared to be the two most important factors that increase the risk of developing neurological disorders. Experimental animal data showed that PM 2.5 potently damaged the brain and intestines of AD mice, and that the toxicological mechanisms of this PM 2.5 -mediated brain injury led to morphological changes, inflammation, and perturbation of miRNA/mRNA regulation in the brain. These data suggest that PM 2.5 inhalation also have modulatory effects on the abundance and diversity of intestinal bacteria in AD mice. The findings of this study have clarified positive relationships between environmental and biological factors and neurological disorders and have elucidated the potential mechanisms by which PM 2.5 may mediate the initiation or exacerbation of AD
140

Absorption of caffeine through isolated rat small intestine

Hatch, William James 01 August 1974 (has links)
Intestines of fifty-six albino rats of the Holtzman strain were removed and perfused with Krebs bicarbonate buffered solutions containing caffeine. After one hour of absorbtion, caffeine was extracted from the serosal fluids in chloroform and concentrations were determined spectrophotometrically. It was found that all portions of the small intestine transported caffeine against a concentration gradient. This transport mechanism demonstrated saturation kinetics and was inhibited by ouabain. It was concluded that the movement of caffeine from the mucosa to the serosa of the small intestine cannot be the result of simple diffusion. Possible mechanisms by which the absorption of caffeine takes place are discussed.

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