BIO Bragg gratings on microfibers for label-free biosensing
[EN] Discovering nanoscale phenomena to sense biorecognition events introduces new perspectives to exploit nano science and nanotechnology for bioanalytical purposes. Here we present Bio Bragg Gratings (BBGs), a novel biosensing approach that consists of diffractive structures of protein bioreceptors patterned on the surface of optical waveguides, and tailored to transduce the magnitude of biorecognition assays into the intensity of single peaks in the reflection spectrum. This work addresses the design, fabrication, and optimization of this system by both theoretical and experimental studies to explore the fundamental physicochemical parameters involved. Functional biomolecular gratings ar…
Early detection of lung cancer in exhaled breath condensate using miRNA markers
Background: Lung cancer is the leading cause of death by cancer worldwide. Since 5-year survival rate increases significantly when lung cancer is diagnosed at early stages, the development of accurate non-invasive biomarkers for early lung cancer diagnosis is of utmost importance. Over the last years, several tumour biomarkers based on microRNAs (miRNAs) determined in exhaled breath condensate (EBC) have been evaluated and could be applied to early diagnosis of lung cancer. Rationale: miRNA signatures for surgical specimens of lung cancer have been determined providing a panel of differentially expressed miRNAs that were able to discriminate lung cancer patients from normal subjects. Using …
JAK2 mediates lung fibrosis, pulmonary vascular remodelling and hypertension in idiopathic pulmonary fibrosis: an experimental study
BackgroundPulmonary hypertension (PH) is a common disorder in patients with idiopathic pulmonary fibrosis (IPF) and portends a poor prognosis. Recent studies using vasodilators approved for PH have failed in improving IPF mainly due to ventilation (V)/perfusion (Q) mismatching and oxygen desaturation. Janus kinase type 2 (JAK2) is a non-receptor tyrosine kinase activated by a broad spectrum of profibrotic and vasoactive mediators, but its role in PH associated to PH is unknown.ObjectiveThe study of JAK2 as potential target to treat PH in IPF.Methods and resultsJAK2 expression was increased in pulmonary arteries (PAs) from IPF (n=10; 1.93-fold; P=0.0011) and IPF+PH (n=9; 2.65-fold; P<0.00…
BIO-Bragg gratings: structured molecular networks for on-fiber bioanalysis
The research on photonic biosensors is a scientific hot topic at the moment, with a significant potential impact on industry and medicine. Label-free, miniaturized, inexpensive and low-loss biosensors are developed based on optical fiber technology. Our approach is based on a Bio-Bragg-Grating (BBG) patterned on the surface of a microfiber. We present the design, fabrication and proof of concept of our device, as well as its multiplexing and tunability perspectives [1] .
Denaturing for Nanoarchitectonics: Local and Periodic UV-Laser Photodeactivation of Protein Biolayers to Create Functional Patterns for Biosensing
[EN] The nanostructuration of biolayers has become a paradigm for exploiting nanoscopic light-matter phenomena for biosensing, among other biomedical purposes. In this work, we present a photopatterning method to create periodic structures of biomacromolecules based on a local and periodic mild denaturation of protein biolayers mediated by UV-laser irradiation. These nanostructures are constituted by a periodic modulation of the protein activity, so they are free of topographic and compositional changes along the pattern. Herein, we introduce the approach, explore the patterning parameters, characterize the resulting structures, and assess their overall homogeneity. This UV-based patterning…
Hypoxemia Adds to the CURB-65 Pneumonia Severity Score in Hospitalized Patients With Mild Pneumonia
BACKGROUND: Hypoxemia may influence the prognosis of patients with mild pneumonia, regardless of the initial CURB-65 score (confusion, blood urea nitrogen > 20 mg/dL, respiratory rate > 30 breaths/min, blood pressure < 90/60 mm Hg, and age ≥ 65 y). OBJECTIVE: To determine the risk factors associated with hypoxemia and the influence of hypoxemia on clinical outcomes in hospitalized patients with mild pneumonia. METHODS: We performed a multicenter prospective cohort study of 585 consecutive hospitalized patients with mild pneumonia (CURB-65 groups 0 and 1). We stratified the patients according to the presence of hypoxemia, defined as a PaO2/FIO2 < 300 mm Hg on admission. We assessed the risk …
Is it possible to predict which patients with mild pneumonias will develop hypoxemia?
SummaryUsually, mortality due to mild community-acquired pneumonias (CAP) (Pneumonia severity index (PSI) classes I–III) is low (<3%), but the appearance of hypoxemia significantly increases mortality. Our aim was to determine the clinical parameters associated with risk factors of developing hypoxemia in subjects with mild CAP (PSI I–III) and the clinical outcomes of the hypoxemic group.We analyzed clinical characteristics and the outcomes of patients with mild CAP and hypoxemia (PaO2/FiO2<300), in a prospective, multicenter cohort study of 1195 patients.Mild pneumonias (PSI I–III) were found in 645 cases (53.9%), of which 217 (33.6%) presented hypoxemia according to a PaO2/FiO2<300. Patie…