Distinction between rhinovirus-induced acute asthma and asthma-augmented influenza infection.

BACKGROUND: Rhinovirus (RV) is an established trigger of asthma attacks, whereas such a link is less consistent for influenza virus (IFV). OBJECTIVE: In the context of precision medicine, we hypothesized that IFV infection may cause a condition essentially different from RV, and we investigated this by evaluating clinical characteristics of RV/IFV-positive and -negative children with respiratory symptoms and/or fever. METHODS: One thousand two hundred and seven children, 6 months to 13 years old, hospitalized for flu-like illness were recruited in this cross-sectional study. Collected information included demographics, medical history, symptoms/physical findings/diagnosis at presentation and treatment. Nasal secretions were PCR-tested for IFV/RV. Associations were evaluated with adjusted logistic regression models. RESULTS: Rhinovirus positivity was associated with an asthma-like presentation, including increased wheeze/effort of breathing/diagnosis of acute asthma, and decreased fever/vomiting. Conversely, IFV+ children presented with less wheeze/effort of breathing/diagnosis of acute asthma, while they were more frequently febrile. In those with previous asthma history, both viruses induced wheeze; however, IFV was uniquely associated with a more generalised and severe presentation including fever, rales, intercostal muscle retractions and lymphadenopathy. These symptoms were not seen in RV+ asthmatics, who had fewer systemic signs and more cough. CONCLUSIONS AND CLINICAL RELEVANCE: In children with respiratory symptoms and/or fever, RV but not IFV is associated with wheeze and an asthma-like presentation. In those with an asthma history, IFV causes more generalised and severe disease that may be better described as "asthma-augmented influenza" rather than an "asthma attack." Differences in the acute conditions caused by these viruses should be considered in the design of epidemiological studies.

Measurement of lentiviral vector titre and copy number by cross-species duplex quantitative PCR.

Lentiviruses are the vectors of choice for many preclinical studies and clinical applications of gene therapy. Accurate measurement of biological vector titre before treatment is a prerequisite for vector dosing, and the calculation of vector integration sites per cell after treatment is as critical to the characterisation of modified cell products as it is to long-term follow-up and the assessment of risk and therapeutic efficiency in patients. These analyses are typically based on quantitative real-time PCR (qPCR), but as yet compromise accuracy and comparability between laboratories and experimental systems, the former by using separate simplex reactions for the detection of endogene and lentiviral sequences and the latter by designing different PCR assays for analyses in human cells and animal disease models. In this study, we validate in human and murine cells a qPCR system for the single-tube assessment of lentiviral vector copy numbers that is suitable for analyses in at least 33 different mammalian species, including human and other primates, mouse, pig, cat and domestic ruminants. The established assay combines the accuracy of single-tube quantitation by duplex qPCR with the convenience of one-off assay optimisation for cross-species analyses and with the direct comparability of lentiviral transduction efficiencies in different species.

Comparative Evaluation of Human Mesenchymal Stem Cells of Fetal (Wharton's Jelly) and Adult (Adipose Tissue) Origin during Prolonged In Vitro Expansion: Considerations for Cytotherapy.

Mesenchymal stem cells (MSCs) are somatic cells with a dual capacity for self-renewal and differentiation, and diverse therapeutic applicability, both experimentally and in the clinic. These cells can be isolated from various human tissues that may differ anatomically or developmentally with relative ease. Heterogeneity due to biological origin or in vitro manipulation is, nevertheless, considerable and may equate to differences in qualitative and quantitative characteristics which can prove crucial for successful therapeutic use. With this in mind, in the present study we have evaluated the proliferation kinetics and phenotypic characteristics of MSCs derived from two abundant sources, that is, fetal umbilical cord matrix (Wharton's jelly) and adult adipose tissue (termed WJSC and ADSC, resp.) during prolonged in vitro expansion, a process necessary for obtaining cell numbers sufficient for clinical application. Our results show that WJSC are derived with relatively high efficiency and bear a substantially increased proliferation capacity whilst largely sustaining the expression of typical immunophenotypic markers, whereas ADSC exhibit a reduced proliferation potential showing typical signs of senescence at an early stage. By combining kinetic with phenotypic data we identify culture thresholds up to which both cell types maintain their stem properties, and we discuss the practical implications of their differences.

Viruses and bacteria in acute asthma exacerbations--a GA² LEN-DARE systematic review.

A major part of the burden of asthma is caused by acute exacerbations. Exacerbations have been strongly and consistently associated with respiratory infections. Respiratory viruses and bacteria are therefore possible treatment targets. To have a reasonable estimate of the burden of disease induced by such infectious agents on asthmatic patients, it is necessary to understand their nature and be able to identify them in clinical samples by employing accurate and sensitive methodologies. This systematic review summarizes current knowledge and developments in infection epidemiology of acute asthma in children and adults, describing the known impact for each individual agent and highlighting knowledge gaps. Among infectious agents, human rhinoviruses are the most prevalent in regard to asthma exacerbations. The newly identified type-C rhinoviruses may prove to be particularly relevant. Respiratory syncytial virus and metapneumovirus are important in infants, while influenza viruses seem to induce severe exacerbations mostly in adults. Other agents are relatively less or not clearly associated. Mycoplasma and Chlamydophila pneumoniae seem to be involved more with asthma persistence rather than with disease exacerbations. Recent data suggest that common bacteria may also be involved, but this should be confirmed. Although current information is considerable, improvements in detection methodologies, as well as the wide variation in respect to location, time and populations, underline the need for additional studies that should also take into account interacting factors.

Performance of rapid influenza testing in hospitalized children.

Influenza infection is associated with high hospitalization rates among young children. Rapid diagnosis of influenza infection is particularly useful in order to prevent nosocomial infection and allows for the timely initiation of antiviral treatment. We evaluated the performance of a rapid influenza test in hospitalized children during the influenza season. All children (aged 6 months to 14 years) hospitalized with fever and/or respiratory symptoms, admitted during the 2005 influenza season, participated in the study. A multiplex reverse transcriptase polymerase chain reaction (RT-PCR), able to identify IFV-A H1N1, H3N2, and IFV-B subtypes, was performed on nasopharyngeal aspirates. The nasal swab was tested with a lateral-flow immunoassay (QuickVue Influenza Test). The performance of the rapid test was compared with the results of PCR. Influenza infection was diagnosed by PCR in 41/217 (19%) patients. Infection with influenza A virus (H3N2) was diagnosed in all cases. The performance of the QuickVue Influenza Test was estimated as follows: sensitivity 67.5%, specificity 96%, positive predictive value 79%, and negative predictive value 93%. The sensitivity of the test was higher in infants aged 6-12 months, in those with short duration of symptoms, and in the peak phase of the epidemic. The QuickVue Influenza Test is useful and reasonably accurate to detect influenza infection in hospitalized children during the influenza season. Infection with influenza virus is unlikely if the test is negative. A positive result suggests that infection is probable if influenza virus circulates in the community.

Budesonide and formoterol inhibit inflammatory mediator production by bronchial epithelial cells infected with rhinovirus.

BACKGROUND: Rhinoviruses (RVs) are responsible for the majority of acute asthma and chronic obstructive pulmonary disease (COPD) exacerbations. RVs infect the lower airways and induce the production of pro-inflammatory and remodelling-associated mediators. Budesonide (BUD) and formoterol (FORM) synergize in controlling asthma and COPD exacerbations; however, their effects on virus-induced inflammation and remodelling are less known. OBJECTIVE: We investigated whether BUD and FORM synergize in suppressing RV-induced inflammation and remodelling in the airways. METHODS: In vitro models of RV infection of BEAS-2B and primary normal human bronchial epithelial (NHBE) cells were used. We assessed the effects of individual and combined drugs administered post-infection, at a clinically relevant concentration range (10(-6)-10(-10) m), on the production of CCL5, CXCL10, CXCL8, IL-6 and the remodelling-associated VEGF and bFGF, using ELISA and RT-PCR. RESULTS: BUD effectively suppressed RV-mediated induction of all mediators studied, in a concentration-dependent manner. FORM alone suppressed the production of CXCL8 and bFGF. The combination of BUD and FORM had concentration-dependent, additive or synergistic effects in the suppression of RV-induced CCL5, CXCL8 and CXCL10 in both cell types as well as VEGF in NHBE only. Combination treatment also resulted in an enhanced suppression of RV-induced IL-6, and CCL5 at the mRNA level as compared with BUD or FORM alone. CONCLUSION: BUD and FORM suppress RV-induced chemokines and growth factors in bronchial epithelial cells in a concentration-dependent, synergistic or additive manner. These data further support the combined use of BUD and FORM in asthma and COPD and intensification of this therapy during exacerbations.

Bone tissue formation from human embryonic stem cells in vivo.

Although the use of embryonic stem cells in the assisted repair of musculoskeletal tissues holds promise, a direct comparison of this cell source with adult marrow-derived stem cells has not been undertaken. Here we have compared the osteogenic differentiation potential of human embryonic stem cells (hESC) with human adult-derived stem cells in vivo. hESC lines H7, H9, the HEF-1 mesenchymal-like, telomerized H1 derivative, the human embryonic kidney epithelial cell line HEK293 (negative control), and adult human mesenchymal stem cells (hMSC) were either used untreated or treated with osteogenic factors for 4 days prior to injection into diffusion chambers and implantation into nude mice. After 11 weeks in vivo chambers were removed, frozen, and analyzed for evidence of bone, cartilage, and adipose tissue formation. All hESCs, when pretreated with osteogenic (OS) factors gave rise exclusively to bone in the chambers. In contrast, untreated hESCs (H9) formed both bone and cartilage in vivo. Untreated hMSCs did not give rise to bone, cartilage, or adipose tissue in vivo, while pretreatment with OS factors engendered both bone and adipose tissue. These data demonstrate that hESCs exposed to OS factors in vitro undergo directed differentiation toward the osteogenic lineage in vivo in a similar fashion to that produced by hMSCs. These findings support the potential future use of hESC-derived cells in regenerative medicine applications.

The reliability of frozen-section diagnosis in various breast lesions: a study based on 3451 biopsies.

In this study, we analyze breast biopsy material over a 5-year period and we compare the results of frozen-section diagnosis with the corresponding diagnosis of the permanent histologic sections. In this study, which represents the largest series in the available international literature, it is proven that frozen-section diagnosis of various breast lesions is a highly accurate procedure in spite of the difficulties facing the pathologist with the frequent borderline or premalignant lesions. The great responsibility of the pathologist is emphasized.