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Errata inserted. / Bibliography: leaves 98-120. / x, 120, [4] leaves, [13] leaves of plates : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This study is concerned with the identification of genes related to the very early stages of meiosis when homologous pairing occurs. A cDNA library is prepared at the premeiotic interphase and prophase stages of meioses. Differential screening is used to identify and select clones showing preferential expression in anthers at early meiosis. Two selected clones are chosen for further analysis and to investigate a possible role in chromosome pairing. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Science, 1997

Thesis (Ph.D.)--University of California, San Francisco, 2004. / Bibliography: leaves 161-169. Also available online.

Proefschrift Universiteit Maastricht. / Met bibliogr., lit. opg. - Met samenvatting in het Nederlands.

γ-aminobutyric acid is the major inhibitory neurotransmitter in the adult mammalian central nervous system (CNS) and may also play a neurotrophic role during CNS development. Diversification of GABA_A receptor mediated responses are in part a result ofvariation in subunit composition in the receptor complex. This variation arises both from the number of different subtypes of GABA_A receptor subunits (α1-6, β1-4, γ1-3, δ1, ρ1-3, ε, ρ), as well as from post-transcriptional processes such as RNA splicing. In this thesis, I have investigated the developmental onset of GABA_A receptor gene expression and the distribution and temporal expression of GABA_A receptor subunit mRNAs and 12 splice variants within the developing and adult murine CNS. Preliminary studies using S 1 nuclease protection analysis demonstrated that α1, β3 and γ2 were the predominant subtypes of GABA_A receptor subunits expressed at embryonic day 14 and in the adult murine CNS. In situ hybridisation analysis demonstrated overlapping but distinct spatial and temporal patterns of GABA_A subunit mRNA expression during postnatal development and in the adult murine CNS. Analysis of γ2 mRNA splice variants demonstrated that the γ2S transcript is the predominant γ2 mRNA expressed during latter stages of embryo genesis, while the γ2L transcript is the predominant γ2 isoform present inthe adult CNS. Since there is a 29 to 47 percent amino acid identity among the various GABA_A receptor subunits, I have also demonstrated through site-directed mutagenesis studies, that changes in a conserved amino acid in the cysteine loop of the bovine a 1 GABA_A receptor subunit resulted in a loss of agonist and antagonist binding (DI49N), while a change in a conserved amino acid in the M1 transmembrane domain of the bovine α1 GABA_A receptor subunit resulted in loss of agonist binding and reduction in the B_max and K_d for antagonist binding (P243A). 'These results are in contrast to the effect of identical mutations in the bovine β1 subunit and suggest that if the pentameric GABA_A receptor assembly is composed of (α1)2(β1)1(γ2)2, then changes in highly conserved amino acids in the α1 receptor subunit would have a greater distortion on the structure of the receptor complex.

Orientadores: Pablo Agustin Vargas, Lynne Bingle / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-13T01:09:27Z (GMT). No. of bitstreams: 1 Silva_AndreiaAparecidada_D.pdf: 22491420 bytes, checksum: 91def4321f81cbc12963ed48ee86d77d (MD5) Previous issue date: 2009 / Resumo: Introdução: Inúmeras lesões de origem infecciosa, cística, neoplásica e inflamatória foram reportadas nas glândulas salivares de pacientes HIV+. Objetivos: Os objetivos deste trabalho foram analisar e comparar a resposta do sistema imune inato (proteínas da família PLUNC) em glândulas salivares maiores, provenientes de pacientes autopsiados com AIDS e sem AIDS (grupo controle) no Departamento de Patologia da Faculdade de Medicina da Universidade Estadual de São Paulo (FMUSP) no período de 1996 a 2000. Material e Métodos: Os pacientes autopsiados foram divididos em 05 grupos: grupo 01- controle (pacientes HIV negativos), grupo 02- HIV+ sem alterações nas glândulas salivares maiores, grupo 03- (micobacteriose), grupo 04 (citomegalovirose) e grupo 05 (sialadenite) para a realização de reações de imunohistoquímica para os anticorpos SPLUNC 1, SPLUNC 2 A, SPLUNC 2B e LPLUNC 1. Para o grupo controle foi realizado técnica de hibridização in situ para SPLUNC 2. Resultados: a média de idade dos pacientes selecionados para o grupo controle foi de 60,92 anos + 9,48 anos enquanto que a média de idade dos pacientes HIV positivos foi de 37,75 anos + 11,11. Nos casos de micobacteriose e citomegalovirose foi observada maior intensidade de marcação nas regiões próxima a área de infecção, quando comparada com áreas na periferia da lesão para os anticorpos SPLUNC 2 A e 2B. O anticorpo LPLUNC 1 foi positivo apenas nos ductos salivares e apresentou positividade em 42,22%, 51,06% e 63,88% para as glândulas parótida, submandibular e sublingual respectivamente. Com relação à hibridização in situ, foi observado positividade em todos os casos. Conclusão: a família de proteínas PLUNC pode ter papel fundamental na proteção dos organismos frente a agentes infecciosos, no entanto são necessários maiores estudos. / Abstract: Objectives: The aim of this study was to determine the expression of PLUNC proteins in major salivary glands (MSG) of AIDS patients with or without infectious conditions and non-HIV patients using post-mortem material. Methods: Sex, age, CD4 cell count, and clinical history were obtained retrospectively from the clinical records of all patients (n=63). We analysed the expression of PLUNCs (SPLUNC1, SPLUNC2, LPLUNC1) using immunohistochemistry in parotid (n=45), submandibular (n=47) and sublingual gland (n=37) samples of AIDS patients [30 with normal histology, 21 with mycobacteriosis, 14 with cytomegalovirus (CMV) infection, 30 with chronic nonspecific sialadenitis, and 30 HIV-negative controls. In situ hybridization (ISH) for SPLUNC2 in the MSG of the HIVnegative group was performed. Immunoreactivity was assessed as positive or negative. Results: The mean age of the patients who died of AIDS (n=63) and CD4 cell count (n=44) were 37 years and 63 cells microL(-1), respectively. The mean age of the HIV negative patients was 61 years. SPLUNC 1 expression was detected in the mucous acini of submandibular and sublingual glands, and SPLUNC2 was seen in the serous cells of the MSG. LPLUNC 1 expression was only positive in the salivary ducts of the MSG. There was a higher expression of SPLUNC2 in AIDS patients with CMV infection and mycobacteriosis when compared with all other groups. The intensity of staining for SPLUNC2 was greater around the lesions than the peripheral ones. There were no significant differences between control subjects and AIDS patients without histologic alterations or with chronic nonspecific sialadenitis. ISH for SPLUNC 2 showed perinuclear positivity in the serous cells in all HIV-negative cases. Conclusions: SPLUNC1 and LPLUNC1 proteins were similarly expressed in the MSG of AIDS patients and non-HIV patients. CMV infection and mycobacteriosis increase SPLUNC2 expression in serous cells in the MSG of AIDS patients. Further studies are needed to understand the biological processes involved in SPLUNC2 expression in the MSG infected by CMV and mycobacteriosis. / Doutorado / Patologia / Doutor em Estomatopatologia

Natural killer (NK) cells, lymphocytes of the innate immune system, can recognize a wide array of cells via several receptors families such as Ly49 and NKR-P1. The Nkrp1 gene family encode for C-type lectin-like receptors which can recognize their ligands, Clr, on target cells. Nkrp1 and Clr genes are intertwined in the NK gene complex and are thus inherited together. The Nkrp1-Clr genes in 129S6 and BALB/c mouse strains show significant sequence polymorphism compared to those of C57BL/6 mice while the overall gene organization and gene number are conserved. RT-PCR was utilized to study the expression of individual Nkrp1-Clr genes. In situ hybridization was performed to validate expression results from RT-PCR, as well as to verify the cell types in which Nkrp1-Clr genes are expressed. Surprisingly, our expression studies reveal an interesting pattern of expression of Nkrp1 and Clr genes not only in lymphoid tissues but also in the epithelial cells of the intestine, kidney, eye and lung, the myocytes of the heart and skeletal muscle, and possibly some endothelial cells, indicating novel functions of NK cells in these tissues.

Mitochondria are intracellular organelles responsible for oxidative phosphorylation. They contain their own DNA which encodes some components involved in oxidative phosphorylation. Mitochondrial DNA is very susceptible to mutations. Mitochondrial abnormalities have been observed in several disorders of muscle and brain. Alzheimer's disease is a form of dementia characterized by the formation of numerous neuritic plaques and neurofibrillary tangles. There is evidence suggesting a possible role for mitochondrial abnormalities in Alzheimer's disease. The goal of this project was to determine if there were quantitative changes in mitochondrial DNA content in large neurons from Alzheimer's disease patients, compared to age-matched control patients. The relative mitochondrial DNA content per unit area was assessed in brain sections from Alzheimer's disease subjects and age-matched control subjects using in situ hybridization to mitochondrial DNA. The results were not conclusive due to technical concerns with the in situ hybridization technique which are discussed. / Thesis / Master of Science (MS)

The chicken yolk sac and small intestine are connected through the yolk stalk and share many biological similarities. During the embryonic stage, the extra-embryonic yolk sac helps the embryo to absorb nutrients primarily in the last two weeks of incubation. The chicken yolk sac physically moves yolk contents from the yolk sac to the small intestine at the end of embryogenesis. This is the time when the small intestine replaces the yolk sac in assimilating nutrients for the embryo and later for the posthatch chicken. Additionally, both chicken small intestinal epithelia and the yolk sac secrete beta defensins for promoting intestinal health. Since there are heterogeneous cell types along the mammalian intestinal villus, which are derived from the intestinal stem cells in the crypts, we investigated if cells of the chicken yolk sac and small intestine have the same ontogeny as mammalian intestinal epithelial cells. In this dissertation, we mainly focused on the spatial expression of nutrient transporters (PepT1 and SGLT1), intestinal stem cell markers (Lgr5 and Olfm4), and avian beta defensins in the chicken yolk sac and small intestine during the embryonic and early posthatch stages. RNAscope in situ hybridization was used to identify the distribution of cells expressing PepT1 mRNA in both the chicken yolk sac and small intestine. PepT1 mRNA was found to be expressed by epithelial cells in both the yolk sac and small intestine. In the yolk sac, PepT1 mRNA was uniformly distributed in each endodermal epithelial cell along the villus-like structure. The pattern of PepT1 mRNA expression observed in the chicken yolk sac during the last 10 days of incubation revealed that PepT1 mRNA was increased from e11 to e13, and decreased from e15 to day of hatch. The peak of PepT1 mRNA expression was between e13 and e15, when the yolk sac reaches maximum absorptive area and the growth of the chicken embryo is at its fastest rate. However, the expression of PepT1 mRNA in the intestine was only detected in columnar enterocytes along the villus and not in goblet cells or cells in the crypts. The immunofluorescence assay confirmed that PepT1 protein was located at the brush border membrane of the enterocytes and that protein expression of PepT1 was restricted to the intestinal epithelial cells from approximately the middle to the tip of the villus. In order to identify intestinal stem cells, we used the known mammalian stem cell markers, Lgr5 and Olfm4. Both Lgr5 and Olfm4 are specifically expressed by cells in the chicken intestinal crypts, suggesting that they can be used as biomarkers for chicken intestinal stem cells. Dual labelling of PepT1 and Olfm4 mRNA on the same chicken intestinal sample revealed that there was a gap between PepT1-expressing enterocytes and Olfm4-expressing intestinal stem cells. The cells in this gap were presumably transit amplifying (TA) cells. Additionally, we also found that the TA cell zone along the intestinal villus was reduced during chicken growth. This TA cell population could be clearly detected at day of hatch and d1 posthatch but not later. The expression of SGLT1 mRNA was localized to yolk sac endodermal epithelial cells and showed a sharp increase at the end of incubation. This increase of SGLT1 mRNA coincided with the increase in glucose in the yolk, indicating that the chicken embryo needs glucose as energy for hatching. The mRNA expression profiles of various avian beta defensins have been examined by qPCR and in situ hybridization to investigate the immune function of the yolk sac and small intestine. We found that AvBD10 mRNA showed the highest expression level in the yolk sac and was expressed predominantly in the yolk sac endodermal epithelial cells. Additionally, the expression of AvBD10 mRNA showed a development-specific pattern, which increased from e9 to e11, and decreased from e13 towards day of hatch. The expression patterns of AvBD1, 2, and 7 mRNA were similar to each other. These three genes were found to be expressed by chicken heterophils distributed in the yolk sac blood islands and small intestinal blood vessels. Only a subset of heterophils, which might be activated, were able to express AvBD1, 2, and 7 mRNA. In the intestine, the expression of AvBD10 mRNA was localized to cells along the villus at e19 and day of hatch, but later to only a few cells located above the intestinal crypts. In summary, the endodermal epithelial cells are responsible for the absorptive and immune functions of the chicken yolk sac. The yolk sac mesoderm is critical for embryonic hematopoiesis and innate immunity. The chicken small intestinal epithelial cells are derived from the intestinal stem cells in the crypts. These epithelial cells have different cell types, which are functioning to absorb nutrients and secrete antimicrobial peptides. / Ph. D. / The chicken yolk sac and small intestine are connected to each other and share many biological similarities. Both chicken small intestinal and yolk sac epithelia play critical roles for nutrient absorption and immune defense. In this dissertation, the mRNA for nutrient transporters such as the peptide transporter, PepT1 and the sodium-glucose co-transporter, SGLT1 were found to be expressed by absorptive epithelial cells in both the yolk sac and small intestine. Additionally, both intestinal and yolk sac epithelial cells expressed avian beta defensins (AvBDs), which are important chicken host defense peptides. In the small intestine, there are a number of differentiated cell types that originate from stem cells in the crypt that express the known mammalian stem cell markers, Olfm4 and Lgr5 mRNA. However, in the chicken yolk sac, only the stem cell marker Lgr5 mRNA was expressed by endothelial cells. In summary, the yolk sac epithelial cells are responsible for the absorptive and immune functions for the embryonic stage. The chicken small intestinal epithelial cells are derived from the intestinal stem cells in the crypts. These epithelial cells have different cell types, which function to absorb nutrients and secrete antimicrobial peptides.

No description available.