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1.
Neuroimaging in Pineal Tumors 总被引:4,自引:0,他引:4
F Reis MD AV Faria MD PhD VA Zanardi MD PhD JR Menezes MD F Cendes MD PhD LS Queiroz MD PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread. 相似文献
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Lajoie J Zijenah LS Faucher MC Ward BJ Roger M;ZVITAMBO Study Group 《Human immunology》2003,64(8):823-829
Because of the essential role of transporter associated with antigen processing (TAP1 or TAP2) molecule in antigen processing, the implication of its polymorphism as a factor involved in human diseases and the possible genetic variation at this locus among ethnically diverse populations, we underwent a study to analyze the full extent of TAP1 polymorphism in an indigenous Zimbabwean population (Shona ethnic group). Using single-stranded conformation polymorphism and DNA direct sequencing procedures, we detected the presence of 11 nucleotide sequence variations in the entire coding region of TAP1. Of these variants, eight are nonconservative substitutions with respect to amino acid composition and are located in a critical part of the protein that could modulate its function. Five new polymorphic sites were identified in exon 1 (codons 7 Pro --> Ser, 17 Gly --> Arg, 141 Val --> Val), exon 6 (codon 419 Gly --> Cys), and exon 7 (codon 487 Arg --> Arg). Significant differences were seen in the distribution of TAP1*0201 and TAP1*0401 alleles, and codon 333 (Ile --> Val) polymorphism among African and non-African populations. Thus, TAP1 polymorphism has evolved differently among populations presumably because of the evolutionary pressures generated by prevalent pathogens in these geographically distinct regions. 相似文献
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CYP3A5 genetic polymorphisms in different ethnic populations. 总被引:3,自引:0,他引:3
Jean-Nicholas Roy Julie Lajoie Lynn S Zijenah Azemi Barama Charles Poirier Brian J Ward Michel Roger 《Drug metabolism and disposition》2005,33(7):884-887
Cyp3A5 activity varies within any given ethnic population, suggesting that genetic variation within the Cyp3A5 gene may be the most important contributor to interindividual and interracial differences in Cyp3A-dependent drug clearance and response. The full extent of Cyp3A5 polymorphism in a white and an indigenous African population was analyzed using DNA direct sequencing procedures. The presence of 10 and 12 single nucleotide polymorphisms was detected in the white and African samples, respectively. Thirteen novel mutations occurring at low frequencies were identified in these populations. Significant differences were observed in the distribution of Cyp3A5*3, Cyp3A5*6, and Cyp3A5*7 alleles among white and African populations. The frequency of Cyp3A5*3 allele in white Canadians (approximately 93%) is higher than in Zimbabweans (77.6%) (p < 0.001). In contrast, Cyp3A5*6 and Cyp3A5*7 alleles are relatively frequent in African subjects (10-22%) but absent in white subjects (p < 0.001). These differences may reflect evolutionary pressures generated by environmental factors in geographically distinct regions. However, the genetic polymorphism of Cyp3A5 alone does not explain the interindividual differences in Cyp3A-mediated metabolism. 相似文献
6.
Jiang WZ Jin NY Li ZJ Zhang LS Wang HW Zhang YJ Han WY 《第二军医大学学报》2006,27(4):434-434
To express the core protein of HIV-1 of Chinese prevalent strain (HIV-1 (CN)) in Pichia pastoris, the fulllength gag gene was inserted into the secretory expression vector pHILS1. Linearized recombinant plasmid pHILGAG by Sail was electrotransformed into the yeast strain GS115, and the yeast transformants were identified by PCR. To induce the interest protein to be expressed, the PCR positive transformants were inoculated in the medium of BMGY and BMMY, mRNA of the strain was detected by RT-PCR, and the expressed protein was analyzed by SDS-PAGE, Western blotting and thin layer scanning. mRNA (1.3 kb) was amplified by RT-PCR. SDS-PAGE and Western blotting analysis showed that the molecular mass of the expressed protein was 55 kD, which was similar to the expected value, and the expressed protein could react with McAb to HIV-1 p24. Thin layer scanning analysis demonstrated that the whole amount of the expressed protein was approximately 13 % of the soluble protein in the supernatant. The recombinant yeast had good genetic stability. The optimal expression conditions of the engineering yeast were as follows: BMMY medium, 80-90% of dissolved oxygen, 1% methanol, and 3-day-cultivation course. Gag proteins were expressed under the optimal expression condition and purified via gel filtration chromatography. The purity of the interest protein was up to 85 %. After the purified proteins were inoculated into BALB/c mice, the anti-HIV-1 antibodies in the immunized mice could be detected by Western blotting. 相似文献
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Modern population based oral health management requires a complete understanding of the impact of disease in order to provide efficient and effective oral health care and guidance. Periodontitis is an important cause of tooth loss and has been shown to be associated with a number of systemic conditions. The impact of oral conditions and disorders on quality of life has been extensively studied. However, the impact of periodontitis on quality of life has received less attention. This review summarizes the literature on the impact of periodontitis on oral health‐related quality of life (OHRQoL). Relevant publications were identified after searching the MEDLINE and EMBASE electronic databases. Screening of titles and abstracts and data extraction was conducted. Only observational studies were included in this review. Most of the reviewed studies reported a negative impact of periodontitis on OHRQoL. However, the reporting standards varied across studies. Moreover, most of the studies were conducted in developed countries. 相似文献
10.
Cairo MS; Christensen R; Sender LS; Ellis R; Rosenthal J; van de Ven C; Worcester C; Agosti JM 《Blood》1995,86(7):2509-2515
Neonates, especially those of very low birthweight (VLBW), have an increased risk of nosocomial infections secondary to deficiencies in development. We previously demonstrated that granulocyte-macrophage colony-stimulating factor (GM-CSF) production and mRNA expression from stimulated neonatal mononuclear cells are significantly less than that from adult cells. Recombinant murine GM-CSF administration to neonatal rats has resulted in neutrophilia, increased neutrophil production, and increased survival of pups during experimental Staphylococcus aureus sepsis. In the present study, we sought to determine the safety and biologic response of recombinant human (rhu) GM-CSF in VLBW neonates. Twenty VLBW neonates (500 to 1,500 g), aged < 72 hours, were randomized to receive either placebo (n = 5) or rhuGM-CSF at 5.0 micrograms/kg once per day (n = 5), 5.0 micrograms/kg twice per day (n = 5), or 10 micrograms/kg once per day (n = 5) given via 2-hour intravenous infusion for 7 days. Complete blood counts, differential, and platelet counts were obtained, and tibial bone marrow aspirate was performed on day 8. Neutrophil C3bi receptor expression was measured at 0 and 24 hours. GM-CSF levels were measured by a sandwich enzyme-linked immunosorbent assay at 2, 4, 6, 12, and 24 hours after the first dose of rhuGM-CSF. At all doses, rhuGM-CSF was well tolerated, and there was no evidence of grade III or IV toxicity. Within 48 hours of administration, there was a significant increase in the circulating absolute neutrophil count (ANC) at 5.0 micrograms/kg twice per day and 10.0 micrograms/kg once per day, which continued for at least 24 hours after discontinuation of rhuGM-CSF. When the ANC was normalized for each patient's first ANC, there was a significant increase in the ANC on days 6 and 7 at each dose level. By day 7, all tested doses of rhuGM- CSF resulted in an increase in the absolute monocyte count (AMC) compared with placebo-treated neonates. In those receiving rhuGM-CSF 5.0 micrograms/kg twice per day, there was additionally a significant increase in the day 7 and 8 platelet count. Tibial bone marrow aspirates demonstrated a significant increase in the bone marrow neutrophil storage pool (BM NSP) at 5.0 micrograms/kg twice per day and 10.0 micrograms/kg once per day. Neutrophil C3bi receptor expression was significantly increased 24 hours after the first dose of rhuGM-CSF at 5.0 micrograms/kg once per day. The elimination half-life (T1/2) of rhuGM-CSF was 1.4 +/- 0.8 to 3.9 +/- 2.8 hours.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献