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Acute anterior ischemic optic neuropathy (AION) is a disabling disease which impairs visual function. Standard treatment is unable to affect the outcome and the visual damage persists. We describe the case of a 64-year-old patient affected by AION, whose only known risk factor was hypercholesterolemia. After a first onset of involvement of the right eye (RE), the patient presented four weeks later with an analogous episode affecting the left eye (LE). Since standard treatment, started at involvement of the RE, had not yielded any beneficial effect, the patient underwent three sessions of LDL apheresis. The scotomatous portion of the visual field reduced even after the first session, there was further improvement after the third, and after six months the condition remained stable. Corrected vision improved from 2/10 to 6/10 after the third session. LDL cholesterol and fibrinogen decresade after the third session from 239 mg/dL to 31 mg/dL and from 289 mg/dL to 92 mg/dL, respectively. In conclusion, thanks to its effect of antagonizing hemorheologic disorders of the ocular microcirculation, LDL apheresis seems to be an efficacious treatment of AION, especially in patients suffering from hypercholesterolemia.  相似文献   
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Mutations in the PEX gene at Xp22.1 (phosphate-regulating gene with homologies to endopeptidases, on the X-chromosome), are responsible for X-linked hypophosphataemic rickets (HYP). Homology of PEX to the M13 family of Zn2+ metallopeptidases which include neprilysin (NEP) as prototype, has raised important questions regarding PEX function at the molecular level. The aim of this study was to analyse 99 HYP families for PEX gene mutations, and to correlate predicted changes in the protein structure with Zn2+ metallopeptidase gene function. Primers flanking 22 characterised exons were used to amplify DNA by PCR, and SSCP was then used to screen for mutations. Deletions, insertions, nonsense mutations, stop codons and splice mutations occurred in 83% of families screened for in all 22 exons, and 51% of a separate set of families screened in 17 PEX gene exons. Missense mutations in four regions of the gene were informative regarding function, with one mutation in the Zn2+-binding site predicted to alter substrate enzyme interaction and catalysis. Computer analysis of the remaining mutations predicted changes in secondary structure, N-glycosylation, protein phosphorylation and catalytic site molecular structure. The wide range of mutations that align with regions required for protease activity in NEP suggests that PEX also functions as a protease, and may act by processing factor(s) involved in bone mineral metabolism.   相似文献   
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We analyzed trends over time and determinants of late diagnosis of HIV infection among people diagnosed with AIDS in 1986 to 1998 in a tertiary care center in Rome, Italy. Information on the date of a first HIV test was collected prospectively, in addition to data routinely collected for AIDS reporting. Patients with AIDS were defined as "late testers" if the time interval between first positive HIV test result and AIDS diagnosis was < or = 3 months. Overall, 503 people with AIDS of 1977 included in the analysis (25.4%) were late testers. the proportion of late testers decreased from 62.5% in 1986 to 16% in 1995. Thereafter, this proportion increased to 20.5% in 1996, 33.7% in 1997, and 36.6% in 1998. In multivariate analysis, the following variables were significantly associated with late testing: AIDS diagnosis in years 1986 to 1993 or 1997 to 1998 compared with 1995, male gender, age > or = 45 years, men who have sex with men, heterosexual contacts, or having unknown transmission mode compared with intravenous drug users, and being born outside Italy. Since 1996, the overall number of AIDS cases diagnosed at our center began to decrease whereas the number of late-testing AIDS patients did not decrease, resulting in an increasing proportion of late testers during the last 3 years of the study. This findings may reflect the effect of combination antiretroviral therapy in slowing progression to AIDS of HIV-infected persons aware of their status. A relevant number of people still discover their HIV infection late and may therefore miss treatment opportunities. New testing strategies are needed to reach more people who engage in high-risk behaviors, especially those at risk for sexual transmission, and those born outside Italy.  相似文献   
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Thirty-six cases of enterococcal septicemia in patients with hematological malignancies were reviewed retrospectively and categorized according to their clinical significance using strict previously described definitions. Overall, most of the infected patients were males (77 %), had acute leukemia (64 %), had recently received cytotoxic drug therapy (86 %), were granulocytopenic at the onset of septicemia (77 %), and acquired the infection during hospitalization (77 %). The source of septicemia was unknown in 18 (50 %) patients, intestinal in 15 (42 %) and intravascular in three (8 %). Mortality was 19 % among 21 inpatients who had clinically significant septicemia and 30 % among patients with septicemia of uncertain clinical significance. The fatal outcome could be definitively attributed to enterococcal septicemia in only one of the nine inpatients who died. Clinically significant septicemia appeared somewhat more frequently to be polymicrobial (p=0.06), whereas septicemia of unknown significance presented more frequently as breakthrough septicemia (p=0.013). Unless associated with intravascular infection, enterococcal septicemia in patients with hematological malignancies seems to represent a marker of cytotoxic drug damage of the intestinal mucosa rather than a truly invasive infection.  相似文献   
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J. H. Saurat    L. Galoppin    CL. Ponvert  J. Paupe 《Allergy》1978,33(3):125-129
The leucocyte migration test (LMT) was performed on 20 patients with an intolerance to glafenin--a non-narcotic analgesic drug. LMT was found to be positive in 50% of the subjects with intolerance, a highly significant percentage as compared with the control groups. HSA-glafenin was found to be the most appropriate method for presenting the antigen, but glafenin and its hydroxylated metabolites were only found to induce a migration inhibition in the subjects intolerant to glafenin.  相似文献   
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ObjectiveSensory deficits are important risk factors for delirium but have been investigated in single-center studies and single clinical settings. This multicenter study aims to evaluate the association between hearing and visual impairment or bi-sensory impairment (visual and hearing impairment) and delirium.DesignCross-sectional study nested in the 2017 “Delirium Day” project.Setting and ParticipantsPatients 65 years and older admitted to acute hospital medical wards, emergency departments, rehabilitation wards, nursing homes, and hospices in Italy.MethodsDelirium was assessed with the 4AT (a short tool for delirium assessment) and sensory deficits with a clinical evaluation. We assessed the association between delirium, hearing and visual impairment in multivariable logistic regression models, adjusting for: Model 1, we included predisposing factors for delirium (ie, dementia, weight loss and autonomy in the activities of daily living); Model 2, we added to Model 1 variables, which could be considered precipitating factors for delirium (ie, psychoactive drugs and urinary catheters).ResultsA total of 3038 patients were included; delirium prevalence was 25%. Patients with delirium had a higher prevalence of hearing impairment (30.5% vs 18%; P < .001), visual impairment (24.2% vs 15.7%; P < .01) and bi-sensory impairment (16.2% vs 7.5%) compared with those without delirium. In the multivariable logistic regression analysis, the presence of bi-sensory impairment was associated with delirium in Model 1 [odds ratio (OR) 1.5, confidence interval (CI) 1.2–2.1; P = .00] and in Model 2 (OR 1.4; CI 1.1–1.9; P = .02), whereas the presence of visual and hearing impairment alone was not associated with delirium either in Model 1 (OR 0.8; CI 0.6–1.2, P = .36; OR 1.1; CI 0.8–1.4; P = .42) or in Model 2 (OR 0.8, CI 0.6–1.2, P = .27; OR 1.1, CI 0.8–1.4, P = .63).Conclusions and implicationsOur findings support the importance of routine screening and specific interventions by a multidisciplinary team to implement optimal management of sensory impairments and hence prevention and the management of the patients with delirium.  相似文献   
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