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31.
Lipid abnormalities in HIV-infected patients are not correlated with lopinavir plasma concentrations
32.
Sequence-based typing of Legionella pneumophila serogroup 1 offers the potential for true portability in legionellosis outbreak investigation 总被引:7,自引:0,他引:7
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Seven gene loci of Legionella pneumophila serogroup 1 were analyzed as potential epidemiological typing markers to aid in the investigation of legionella outbreaks. The genes chosen included four likely to be selectively neutral (acn, groES, groEL, and recA) and three likely to be under selective pressure (flaA, mompS, and proA). Oligonucleotide primers were designed to amplify 279- to 763-bp fragments from each gene. Initial sequence analysis of the seven loci from 10 well-characterized isolates of L. pneumophila serogroup 1 gave excellent reproducibility (R) and epidemiological concordance (E) values (R = 1.00; E = 1.00). The three loci showing greatest discrimination and nucleotide variation, flaA, mompS, and proA, were chosen for further study. Indices of discrimination (D) were calculated using a panel of 79 unrelated isolates. Single loci gave D values ranging from 0.767 to 0.857, and a combination of all three loci resulted in a D value of 0.924. When all three loci were combined with monoclonal antibody subgrouping, the D value was 0.971. Sequence-based typing of L. pneumophila serogroup 1 using only three loci is epidemiologically concordant and highly discriminatory and has the potential to become the new "gold standard" for the epidemiological typing of L. pneumophila. 相似文献
33.
34.
Riccardo Castiglia Silvia Garagna Valeria Merico Nicholas Oguge Marco Corti 《Chromosome research》2006,14(5):587-594
We present the results of a cytogenetic study on Mus (Nannomys) minutoides from Kenya by means of C- and G- banding and in-situ fluorescence hybridization (FISH) to localize the telomeric sequences. The karyotype is characterized by the occurrence of
several Rb chromosomes Rb(1.X), Rb(1.Y). Rb(2.17), Rb(3.13), Rb(4.10), Rb(5.11), Rb(6.7), Rb(8.12), not previously described
for this species. This finding suggests a high level of chromosomal diversification, which means it is possible to consider
this cytotype as a new, well-differentiated, chromosomal lineage within the subgenus. The C-banding of the metaphases illustrated
conspicuous blocks of centromeric heterochromatin at the paracentromeric regions of all telocentric chromosomes. Centromeric
heterochromatin is not visible on all biarmed chromosomes. Following hybridization with telomeric probes, bright interstitial
telomeric sequence (ITS) fluorescence signals are evident at the pericentromeric area of all Rb chromosomes, with the exception
of Rb(2.17). Considering the localization of the C-positive heterochromatin and of the telomeric sequences, the events leading
to the Kenyan cytotype from an all-telocentric condition probably included two steps: first, fusion without loss of heterochromatin
and pericentromeric telomeric sequences; second, the reduction of the C-positive satellite DNA followed by the amplification
of telomeric sequences in the C-negative paracentromeric region of Rb chromosomes. The presence of a single Rb(2.17) without
ITS indicates possible variations of this mechanism. 相似文献
35.
Valeria Ascoli Silvia Taccogna Caterina Carnovale Scalzo Francesco Nardi 《Diagnostic cytopathology》1995,12(4):303-308
Using a commercially available monoclonal antibody (Ks20.1) and the avidin-biotin peroxidase method on cytospins and cell blocks, we analyzed cytokeratin (CK) 20 expression in 169 serous effusions. Cytoplasmic staining was observed in 44/151 malignant fluids. Colon, gastric, and pancreatic adenocarcinomas and mucinous ovarian tumors were most frequently positive. Single cases of transitional-cell and squamous cell carcinomas were reactive as well. Lung and breast cancers were mostly negative. Nonmucinous ovarian tumors were invariably unlabeled as were mesotheliomas and normal mesothelial cells. the study shows that CK 20 is valuable in distinguishing tumor cell origin in effusions. in particular, it identifies a set of carcinomas with the majority arising from the gastrointestinal tract, and represents a highly characteristic marker for colorectal cancer. © 1995 Wiley- Liss, Inc. 相似文献
36.
Rudy G E van Eijsden Mike Gerards Lars M T Eijssen Alexandra T M Hendrickx Roselie J E Jongbloed John H J Wokke Rogier Q Hintzen Maria E Rubio-Gozalbo Irenaeus F M De Coo Egill Briem Valeria Tiranti Hubert J M Smeets 《Genetics in medicine》2006,8(10):620-627
PURPOSE: Oxidative phosphorylation is under dual genetic control of the nuclear and the mitochondrial DNA (mtDNA). Oxidative phosphorylation disorders are clinically and genetically heterogeneous, which makes it difficult to determine the genetic defect, and symptom-based protocols which link clinical symptoms directly to a specific gene or mtDNA mutation are falling short. Moreover, approximately 25% of the pediatric patients with oxidative phosphorylation disorders is estimated to have mutations in the mtDNA and a standard screening approach for common mutations and deletions will only explain part of these cases. Therefore, we tested a new CHIP-based screening method for the mtDNA. METHODS: MitoChip (Affymetrix) resequencing was performed on three test samples and on 28 patient samples. RESULTS: Call rates were 94% on average and heteroplasmy detection levels varied from 5-50%. A genetic diagnosis can be made in almost one-quarter of the patients at a potential output of 8 complete mtDNA sequences every 4 days. Moreover, a number of potentially pathogenic unclassified variants (UV) were detected. CONCLUSIONS: The availability of long-range PCR protocols and the predominance of single nucleotide substitutions in the mtDNA make the resequencing CHIP a very fast and reliable method to screen the complete mtDNA for mutations. 相似文献
37.
Valeria?de Mello Coelho Dzung?Nguyen Banabihari?Giri Allyson?Bunbury Eric?Schaffer Dennis?D?TaubEmail author 《BMC immunology》2004,5(1):2
Background
Lipid rafts have been shown to play a role in T cell maturation, activation as well as in the formation of immunological synapses in CD4+ helper and CD8+ cytotoxic T cells. However, the differential expression of lipid raft components between CD4+ and CD8+ T cells is still poorly defined. To examine this question, we analyzed the expression of GM1 in T cells from young and aged mice as well as the expression of the glycosylphosphatidylinositol (GPI)-linked protein Thy-1 and cholesterol in murine CD4+ and CD8+ T cell subpopulations. 相似文献38.
Vincenzo Di Stefano Raffaele Ornello Andrea Gagliardo Angelo Torrente Elisa Illuminato Valeria Caponnetto Ilaria Frattale Raffaella Golini Chiara Di Felice Fabiola Graziano Maria Caccamo Davide Ventimiglia Salvatore Iacono Gabriella Matarazzo Francesco Armetta Giuseppe Battaglia Alberto Firenze Simona Sacco Filippo Brighina 《Nutrients》2021,13(4)
Background: The restrictions taken to control the rapid spread of COVID-19 resulted in a sudden, unprecedented change in people’s lifestyle, leading to negative consequences on general health. This study aimed to estimate the impact of such changes on migraine severity during 2020 March–May lockdown. Methods: Patients affected by migraine with or without aura, diagnosed by expert physicians, completed a detailed interview comprehensive of: assessment of migraine characteristics; measure of physical activity (PA) levels; measure of the intake frequency of main Italian foods; the Insomnia Severity Index (ISI) questionnaire investigating sleep disorders. Results: We included 261 patients with a mean age of 44.5 ± 12.3 years. During social distancing, 72 patients (28%) reported a headache worsening, 86 (33%) an improvement, and 103 (39%) a stable headache frequency. A significant decrease of the PA levels during COVID-19 quarantine in the whole study sample was observed (median total metabolic equivalent task (METs) decreased from 1170 to 510; p < 0.001). Additionally, a significant difference was reported on median ISI scores (from 7 to 8; p < 0.001), which were increased in patients who presented a stable or worsening headache. Conclusions: Our study confirmed that the restrictions taken during the pandemic have affected the practice of PA levels and sleep quality in migraine. Hence, PA and sleep quality should be assessed to find strategies for an improvement in quality of life. 相似文献
39.
Andrea Calcagno Valeria Ghisetti Teresa Emanuele Mattia Trunfio Silvia Faraoni Lucio Boglione Elisa Burdino Sabrina Audagnotto Filippo Lipani Marco Nigra Antonio DAvolio Stefano Bonora Giovanni Di Perri 《Emerging infectious diseases》2021,27(1):303
We measured severe acute respiratory syndrome coronavirus 2 spike protein subunits S1/S2 antibodies by using capillary electrophoresis and a chemiluminescence immunoassay for 5,444 active healthcare workers in Italy. Seroprevalence was 6.9% and higher among participants having contact with patients. Seroconversion was not observed in 37/213 previously infected participants. 相似文献
40.
Jan Höltge Linda Theron Richard G. Cowden Kaymarlin Govender Sally I. Maximo Jennifer S. Carranza Bhumika Kapoor Aakanksha Tomar Angelique van Rensburg Shuang Lu Hongwei Hu Valeria Cavioni Alessia Agliati Ilaria Grazzani Yoel Smedema Gunjanpreet Kaur Kingsley G. Hurlington Jackie Sanders Michael Ungar 《The Journal of adolescent health》2021,68(3):580-588
PurposeIn situations of adversity, young people draw on individual, relational, and contextual (community and cultural) resources to foster their resilience. Recent literature defines resilience as a capacity that is underpinned by a network of interrelated resources. Although empirical studies show evidence of the value of a network approach, little is known regarding how different country contexts influence which resources are most critical within a resource network and how resources interact for adolescent resilience.MethodsNetwork analysis was conducted with data from studies that had used the Child and Youth Resilience Measure. Regularized partial correlation networks of 17 resources were estimated for 14 countries (Botswana, Canada, China, Colombia, Equatorial Guinea, India, Indonesia, Italy, Jordan, New Zealand, the Philippines, Romania, South Africa, and Syrian refugees living in Jordan). The sample size was 18,914 (mean age = 15.70 years, 48.8% female).ResultsWe observed mostly positive associations between the resources of interest. The salience and strength of associations between resources varied by country. The most central resource across countries was having supportive caregivers during stressful times because this resource had the most and strongest positive associations with other resources.ConclusionsThis study gives first empirical evidence from multiple countries that an interplay of social–ecological resources (such as individual skills, peer, caregiver and community support, and educational aspirations and opportunities) matter for adolescent resilience. Across countries, caregiver support appears to be most central for adolescent resilience. Future resilience interventions might apply this network approach to identify important, contextually relevant resources that likely foster additional resources. 相似文献