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41.
Jaime Guevara-Aguirre Arlan L Rosenbloom Marco Guevara-Aguirre Kemal Yariz Jeanette Saavedra Lisa Baumbach Jonathan Shuster 《Growth hormone & IGF research》2007,17(3):261-264
CONTEXT & OBJECTIVE: The Ecuadorian GH receptor deficiency (GHRD)/Laron syndrome population is the only large cohort with a single GHR mutation (E180 splice), permitting identification of numerous carrier and noncarrier first-degree relatives, to ascertain effects of heterozygosity on GH-dependent IGF-I and IGFBP-3 concentrations and on growth. DESIGN: First-degree relatives (n=212) of GHRD patients had specimens taken for IGF-I, IGFBP-3, and GHR genotyping. Normal statured (n=40) and short statured (n=40) unrelated controls had measurement of IGF-I, IGFBP-3, and stature. RESULTS: There were no significant differences between heterozygous and homozygous normal relatives in IGF-I or IGFBP-3 standard deviation scores (SDS). Heterozygous relatives had lower mean height SDS than did homozygous normals, but with extensive overlap between genotype groups in both child and adult relatives. Height SDS in general did not relate to IGF-I or IGFBP-3 concentrations. CONCLUSIONS: GH-dependent IGF-I and IGFBP-3 secretion is not affected by heterozygosity for the E180 splice mutation that causes GHRD/Laron syndrome in the Ecuadorian population. Heterozygosity is associated with reduction in mean statural SDS, but this is not sufficient to be clinically important and not mediated through measurable differences in circulating IGF-I or IGFBP-3 related to genotype. 相似文献
42.
Francesco Landi Ettore Capoluongo Andrea Russo Graziano Onder Matteo Cesari Paola Lulli Angelo Minucci Marco Pahor Cecilia Zuppi Roberto Bernabei 《Growth hormone & IGF research》2007,17(1):58-66
CONTEXT: Increasing evidences from experimental and human studies suggest that the activity of the growth hormone (GH/insulin-like growth factor-I) axis may contribute to the age-related cognitive decline and poor cognition in late life. OBJECTIVE: The aim of the present study was to evaluate the relationship of total serum free IGF-I and its binding protein-3 with cognitive performance in older persons aged 80 years or older. DESIGN: Data are from baseline evaluation of the ilSIRENTE study (n=353). Cognitive performance was evaluated using five items enclosed in the Minimum Data Set for Home Care assessment form: short-term memory, procedural memory, cognitive skills in daily decision making, verbal expression, comprehension. Free insulin-like growth factor-I (free IGF-I) and IGF-binding protein-3 (IGFBP-3) in blood were measured. Analysis of covariance (ANCOVA) was used to examine the relationship between cognitive impairment and the serum free IGF-I and IGFBP-3 concentrations, after adjustment for potential confounding variables. RESULTS: After adjustment for potential confounders, which included age, gender, education, cerebrovascular disease, ischemic heart disease, congestive heart failure, hypertension, diabetes, depression, Parkinson diseases, thyroid diseases, smoking status, alcohol abuse, body mass index, and number of medications, individuals with verbal expression problems (n=20) and individuals with comprehension problems (n=24) had a significantly lower serum levels of readily dissociable IGF-I than participants without cognitive impairments. The serum IGFBP-3 presented the same behavior of free IGF-I. CONCLUSION: The present study suggests that among old-old subjects living in the community lower levels of total serum free IGF-I and IGFBP-3 are associated with impairment of cognitive performance. This finding suggests that the GH/IGF-I axis may play an important role in the age-related decline of cognitive performance. 相似文献
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45.
Hemoglobin adducts of benzo[a]pyrene diolepoxide in newspaper vendors: association with traffic exhaust 总被引:1,自引:0,他引:1
Pastorelli Roberta; Restano Jolanda; Guanci Marco; Maramonte Monica; Magagnotti Cinzia; Allevi Riccardo; Lauri Davide; Fanelli Roberto; Airoldi Luisa 《Carcinogenesis》1996,17(11):2389-2394
Benzo[a]pyrene diol epoxide adducts with hemoglobin (Hb) weremeasured to detect human exposure to environmental benzo[a]pyrenefrom traffic exhaust. Benzo[a]pyrene tetrahydrotetrols (BPTs)released from Hb after acid hydrolysis were quantitated by gaschromatography-mass spectrometry after immunoaffinity chromatography.Fifty three newspaper vendors were enrolled. The median adductconcentration was 0.3 fmol BPTs/mg Hb in high density traffic-exposedvendors and 相似文献
46.
Dario Roccatello Marco Formica Guido Cavalli Maria C. Amprimo Maria G. Pignatelli Paolo Costa Ruggero de Paulis Giacomo Quattrocchio rea Molino Gianbeppe Giordano 《Artificial organs》1990,14(1):69-72
Neutrophil oxidative metabolism, C3d and beta 2 microglobulin levels, were assessed in nine consecutive patients undergoing cardiopulmonary bypass surgery with polypropylene hollow fiber oxygenators for open cardiac operations. Generation of oxygen free radicals by neutrophils was measured as luminol-enhanced chemiluminescence after stimulation with opsonized Zymosan and phorbol myristate acetate. A significant increase in light emission was detected by using both of the chemiluminescence stimulators. Moreover, a remarkable and significant increase in C3d levels was found already at 10 min. Conversely minimal changes in levels of beta 2 microglobulin were detected during cardiopulmonary bypass surgery. These data suggest that the impact of the patient blood with the foreign surface of cardiopulmonary bypass results in activation of phagocyte cells with increased potential in oxygen consumption. These effects could be partially complement-mediated. 相似文献
47.
Expression of tau protein in non-neuronal cells can result in a redistribution of the microtubule cytoskeleton into thick bundles of tau-containing microtubules (Lewis et al.: Nature 342:498-505, 1989; Kanai et al.: J Cell Biol 109:1173-1184, 1989). We reconstituted microtubule bundles using purified tubulin and tau in order to study the assembly of these structures. Taxol-stabilized tubulin polymers were incubated with various concentrations of recombinant human tau and examined by electron microscopy. With increasing concentrations of tau 3 (tau isoform containing three microtubule binding domains) or tau 4 (isoform containing four microtubule binding domains) the microtubules changed orientation from a random distribution to loosely and tightly packed parallel arrays and then to thick cables. In contrast, tau 4L, the tau isoform containing four microtubule binding domains plus a 58-amino acid insert near the N-terminus, showed minimal bundling activity. tau 4-induced bundling could be inhibited by the addition of 0.5 M NaCl or 0.4 mM estramustine phosphate, conditions which are known to inhibit tau binding to microtubules. A tau construct that contained only the microtubule binding domains plus 19 amino acids to the C-terminus was fully capable of bundling microtubules. Phosphorylation of tau 3 with cAMP-dependent protein kinase had no effect on its ability to induce microtubule bundling. These results indicate that tau protein is directly capable of bundling microtubules in vitro, and suggests that different tau isoforms differ in their ability to bundle microtubule filaments. 相似文献
48.
Self-expanding mesh stent for endoscopic palliation of rectal obstructing tumors: a preliminary report 总被引:2,自引:0,他引:2
Summary The endoscopic insertion of self-expanding mesh stents in four patients affected by obstructing rectal malignant tumors is reported. The preliminary experience shows that, in the short term, normal defecation was achieved, with no complications. Longer follow-up is necessary to evaluate the duration and the quality of the palliative effect. 相似文献
49.
Current controversies in oral lichen planus: report of an international consensus meeting. Part 1. Viral infections and etiopathogenesis. 总被引:11,自引:0,他引:11
Giovanni Lodi Crispian Scully Marco Carrozzo Mark Griffiths Philip B Sugerman Kobkan Thongprasom 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2005,100(1):40-51
Despite recent advances in understanding the immunopathogenesis of oral lichen planus (LP), the initial triggers of lesion formation and the essential pathogenic pathways are unknown. It is therefore not surprising that the clinical management of oral LP poses considerable difficulties to the dermatologist and the oral physician. A consensus meeting was held in France in March 2003 to discuss the most controversial aspects of oral LP. Part 1 of the meeting report focuses on (1) the relationship between oral LP and viral infection with special emphasis on hepatitis C virus (HCV), and (2) oral LP pathogenesis, in particular the immune mechanisms resulting in lymphocyte infiltration and keratinocyte apoptosis. Part 2 focuses on patient management and therapeutic approaches and includes discussion on malignant transformation of oral LP. 相似文献
50.
Roberto Marco 《Developmental dynamics》2006,235(4):855-860
In this review article, we shall focus our attention on the initial steps in the research career of José A. Campos-Ortega and the studies he undertook. Particular emphasis will be placed on how these early experiences shaped his personality and his future scientific contributions. 相似文献