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141.
Annaratone L Marchiò C Renzulli T Castellano I Cantarella D Isella C Macrì L Mariscotti G Balmativola D Cantanna E Deambrogio C Pietribiasi F Arisio R Schmitt F Medico E Sapino A 《Translational oncology》2012,5(3):180-189
We investigated whether residual material from diagnostic smears of fine needle aspirations (FNAs) of mammographically detected breast lesions can be successfully used to extract RNA for reliable gene expression analysis. Twenty-eight patients underwent FNA of breast lesions under ultrasonographic guidance. After smearing slides for cytology, residual cells were rinsed with TRIzol to recover RNA. RNA yield ranged from 0.78 to 88.40 μg per sample. FNA leftovers from 23 nonpalpable breast cancers were selected for gene expression profiling using oligonucleotide microarrays. Clusters generated by global expression profiles partitioned samples in well-distinguished subgroups that overlapped with clusters obtained using "biologic scores" (cytohistologic variables) and differed from clusters based on "technical scores" (RNA/complementary RNA/microarray quality). Microarray profiling used to measure the grade of differentiation and estrogen receptor and ERBB2/HER2 status reflected the results obtained by histology and immunohistochemistry. Given that proliferative status in the FNA material is not always assessable, we designed and performed on FNA leftover a multiprobe genomic signature for proliferation genes that strongly correlated with the Ki67 index examined on histologic material. These findings show that cells residual to cytologic smears of FNA are suitable for obtaining high-quality RNA for high-throughput analysis even when taken from small nonpalpable breast lesions. 相似文献
142.
Bonura C Di Carlo P Spicola D Cal C Mammina C Fasciana T Giammanco A 《The new microbiologica》2012,35(2):239-243
Recent reports indicate an increase in rates of infection and disease due to rapidly growing mycobacteria (RGM) in patients with pre-existing chronic lung disease. Studies have described difficulties in correctly identifying closely related species, even when proper methodologies are adopted, and several different gene targets have been proposed. We describe two cases of RGM infection in a 29-year-old HIV-1 positive Congolese man and a 19-year-old HIV-1 positive Liberian woman, respectively, both with bronchiectasis due to previous Mycobacterium tuberculosis (MTB) infection. Mycobacterium porcinum and Mycobacterium bolletii were identified in bronchoalveolar lavage fluid and sputum, respectively. After starting the patients on antiretroviral treatment and primary prophylaxis against non-tuberculous mycobacteria (NTM), and ensuring that they adhered to their prescribed regimen, we observed an improvement in their clinical condition and mycobacteria cleared from their respiratory specimens. Management of RGM respiratory infection in immunocompromised patients has to be evaluated on a case-by-case basis, taking into account the patient's pulmonary sequelae, adherence to multiple treatments and immune profile. 相似文献
143.
Elisabetta Pace Caterina Di Sano Stefania La Grutta Maria Ferraro Giuseppe Albeggiani Giuseppe Liotta Serena Di Vincenzo Carina Gabriela Uasuf Jean Bousquet Mark Gjomarkaj 《PloS one》2012,7(12)
Background
Increased activation and increased survival of T lymphocytes characterise bronchial asthma.Objectives
In this study the effect of budesonide on T cell survival, on inducible co-stimulator T cells (ICOS), on Foxp3 and on IL-10 molecules in T lymphocyte sub-populations was assessed.Methods
Cell survival (by annexin V binding) and ICOS in total lymphocytes, in CD4+/CD25+ and in CD4+/CD25- and Foxp3 and IL-10 in CD4+/CD25+ and in CD4+/CD25-cells was evaluated, by cytofluorimetric analysis, in mild intermittent asthmatics (n = 19) and in controls (n = 15). Allergen induced T lymphocyte proliferation and the in vivo effects of budesonide in mild persistent asthmatics (n = 6) were also explored.Results
Foxp3 was reduced in CD4+/CD25- and in CD4+/CD25+ cells and ICOS was reduced in CD4+/CD25+ cells but it was increased in CD4+CD25-in asthmatics when compared to controls. In asthmatics, in vitro, budesonide was able to: 1) increase annexin V binding and to reduce ICOS in total lymphocytes; 2) increase annexin V binding and Foxp3 and to reduce ICOS in CD4+/CD25- cells; 3) reduce annexin V binding and to increase IL-10 and ICOS in CD4+/CD25+ cells; 4) reduce cell allergen induced proliferation. In vivo, budesonide increased ICOS in CD4+/CD25+ while it increased Foxp3 and IL-10 in CD4+/CD25+ and in CD4+/CD25- cells.Conclusions
Budesonide modulates T cell survival, ICOS, Foxp3 and IL-10 molecules differently in T lymphocyte sub-populations. The findings provided shed light on new mechanisms by which corticosteroids, drugs widely used for the clinical management of bronchial asthma, control T lymphocyte activation. 相似文献144.
145.
Ilse C. E. Hendriksen Juliet Mwanga-Amumpaire Lorenz von Seidlein George Mtove Lisa J. White Rasaq Olaosebikan Sue J. Lee Antoinette K. Tshefu Charles Woodrow Ben Amos Corine Karema Somporn Saiwaew Kathryn Maitland Ermelinda Gomes Wirichada Pan-Ngum Samwel Gesase Kamolrat Silamut Hugh Reyburn Sarah Joseph Kesinee Chotivanich Caterina I. Fanello Nicholas P. J. Day Nicholas J. White Arjen M. Dondorp 《PLoS medicine》2012,9(8)
Background
In African children, distinguishing severe falciparum malaria from other severe febrile illnesses with coincidental Plasmodium falciparum parasitaemia is a major challenge. P. falciparum histidine-rich protein 2 (PfHRP2) is released by mature sequestered parasites and can be used to estimate the total parasite burden. We investigated the prognostic significance of plasma PfHRP2 and used it to estimate the malaria-attributable fraction in African children diagnosed with severe malaria.Methods and Findings
Admission plasma PfHRP2 was measured prospectively in African children (from Mozambique, The Gambia, Kenya, Tanzania, Uganda, Rwanda, and the Democratic Republic of the Congo) aged 1 month to 15 years with severe febrile illness and a positive P. falciparum lactate dehydrogenase (pLDH)-based rapid test in a clinical trial comparing parenteral artesunate versus quinine (the AQUAMAT trial, ISRCTN 50258054). In 3,826 severely ill children, Plasmadium falciparum PfHRP2 was higher in patients with coma (p = 0.0209), acidosis (p<0.0001), and severe anaemia (p<0.0001). Admission geometric mean (95%CI) plasma PfHRP2 was 1,611 (1,350–1,922) ng/mL in fatal cases (n = 381) versus 1,046 (991–1,104) ng/mL in survivors (n = 3,445, p<0.0001), without differences in parasitaemia as assessed by microscopy. There was a U-shaped association between log10 plasma PfHRP2 and risk of death. Mortality increased 20% per log10 increase in PfHRP2 above 174 ng/mL (adjusted odds ratio [AOR] 1.21, 95%CI 1.05–1.39, p = 0.009). A mechanistic model assuming a PfHRP2-independent risk of death in non-malaria illness closely fitted the observed data and showed malaria-attributable mortality less than 50% with plasma PfHRP2≤174 ng/mL. The odds ratio (OR) for death in artesunate versus quinine-treated patients was 0.61 (95%CI 0.44–0.83, p = 0.0018) in the highest PfHRP2 tertile, whereas there was no difference in the lowest tertile (OR 1.05; 95%CI 0.69–1.61; p = 0.82). A limitation of the study is that some conclusions are drawn from a mechanistic model, which is inherently dependent on certain assumptions. However, a sensitivity analysis of the model indicated that the results were robust to a plausible range of parameter estimates. Further studies are needed to validate our findings.Conclusions
Plasma PfHRP2 has prognostic significance in African children with severe falciparum malaria and provides a tool to stratify the risk of “true” severe malaria-attributable disease as opposed to other severe illnesses in parasitaemic African children. Please see later in the article for the Editors'' Summary. 相似文献146.
147.
148.
Mitigation measures for pandemic influenza in Italy: an individual based model considering different scenarios 总被引:1,自引:0,他引:1
Ciofi degli Atti ML Merler S Rizzo C Ajelli M Massari M Manfredi P Furlanello C Scalia Tomba G Iannelli M 《PloS one》2008,3(3):e1790
Background
Individual-based models can provide the most reliable estimates of the spread of infectious diseases. In the present study, we evaluated the diffusion of pandemic influenza in Italy and the impact of various control measures, coupling a global SEIR model for importation of cases with an individual based model (IBM) describing the Italian epidemic.Methodology/Principal Findings
We co-located the Italian population (57 million inhabitants) to households, schools and workplaces and we assigned travel destinations to match the 2001 census data. We considered different R0 values (1.4; 1.7; 2), evaluating the impact of control measures (vaccination, antiviral prophylaxis -AVP-, international air travel restrictions and increased social distancing). The administration of two vaccine doses was considered, assuming that first dose would be administered 1-6 months after the first world case, and different values for vaccine effectiveness (VE). With no interventions, importation would occur 37–77 days after the first world case. Air travel restrictions would delay the importation of the pandemic by 7–37 days. With an R0 of 1.4 or 1.7, the use of combined measures would reduce clinical attack rates (AR) from 21–31% to 0.3–4%. Assuming an R0 of 2, the AR would decrease from 38% to 8%, yet only if vaccination were started within 2 months of the first world case, in combination with a 90% reduction in international air traffic, closure of schools/workplaces for 4 weeks and AVP of household and school/work close contacts of clinical cases. Varying VE would not substantially affect the results.Conclusions
This IBM, which is based on country-specific demographic data, could be suitable for the real-time evaluation of measures to be undertaken in the event of the emergence of a new pandemic influenza virus. All preventive measures considered should be implemented to mitigate the pandemic. 相似文献149.
Thinking about RNA? MicroRNAs in the brain 总被引:1,自引:0,他引:1
Christian Barbato Corinna Giorgi Caterina Catalanotto Carlo Cogoni 《Mammalian genome》2008,19(7-8):541-551
MicroRNAs (miRNAs) are a recently discovered class of small RNA molecules implicated in a wide range of diverse gene regulatory mechanisms. Interestingly, numerous miRNAs are expressed in a spatially and temporally controlled manner in the nervous system. This suggests that gene regulation networks based on miRNA activities may be particularly relevant in neurons. Recent studies show the involvement of RNA-mediated gene silencing in neurogenesis, neural differentiation, synaptic plasticity, and neurologic and psychiatric diseases. This review focuses on the roles of miRNAs in the gene regulation of the nervous system. 相似文献
150.