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1.
Struct Dyn ; 6(6): 064303, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31832487

ABSTRACT

Most chemical and biochemical reactions in nature and in industrial processes are driven by thermal effects that bring the reactants above the energy barrier for reaction. In aqueous solutions, this process can also be triggered by the laser driven temperature jump (T-jump) method, in which the water vibrational (stretch, bend, or combination) modes are excited by a short laser pulse, leading to a temperature increase in the irradiated volume within a few picoseconds. The combination of the laser T-jump with X-ray spectroscopic probes would add element-specificity as well as sensitivity to the structure, the oxidation state, and the spin state of the intermediates of reactions. Here, we present preliminary results of a near infrared pump/X-ray absorption spectroscopy probe to study the ligand exchange of an octahedral aqueous Cobalt complex, which is known to pass through intermediate steps yielding tetrahedral chlorinated as final species. The structural changes of the chemical reaction are monitored with great sensitivity, even in the presence of a mild local increase in temperature. This work opens perspectives for the study of non-light-driven reactions using time-resolved X-ray spectroscopic methods.

2.
Allergy ; 73(3): 635-643, 2018 03.
Article in English | MEDLINE | ID: mdl-28960335

ABSTRACT

BACKGROUND: Patients with asthma present structural and inflammatory alterations that are believed to play a role in disease severity. However, airway remodeling and inflammation have not been extensively investigated in relation to both symptom control and airflow obstruction in severe asthmatics. We aimed to investigate several inflammatory and structural pathological features in bronchial biopsies of severe asthmatics that could be related to symptom control and airflow obstruction after standardized treatment. METHODS: Fifty severe asthmatics received prednisone 40 mg/d for 2 weeks and maintenance therapy with budesonide/formoterol 400/12 µg twice daily + budesonide/formoterol 200/6 µg as needed for 12 weeks. Endobronchial biopsies were performed at the end of 12 weeks. We performed extensive immunopathological analyses of airway tissue inflammation and remodeling features in patients stratified by asthma symptom control and by airflow obstruction. RESULTS: Airway tissue inflammation and remodeling were not associated with symptom control. Asthmatics with persistent airflow obstruction had greater airway smooth muscle (Asm) area with decreased periostin and transforming growth factor beta-positive cells within Asm bundles, in addition to lower numbers of chymase-positive mast cells in the submucosa compared to patients with nonpersistent obstruction. CONCLUSIONS: Symptom control in severe asthmatics was not associated with airway tissue inflammation and remodeling, although persistent airflow obstruction in these patients was associated with bronchial inflammation and airway structural changes.


Subject(s)
Anti-Asthmatic Agents/therapeutic use , Asthma/drug therapy , Asthma/pathology , Bronchi/pathology , Adult , Airway Obstruction/etiology , Airway Obstruction/pathology , Airway Remodeling/drug effects , Airway Remodeling/physiology , Asthma/complications , Budesonide, Formoterol Fumarate Drug Combination/therapeutic use , Female , Humans , Inflammation/pathology , Male , Middle Aged , Prednisone/therapeutic use
3.
Clin Exp Allergy ; 42(10): 1459-71, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22994343

ABSTRACT

BACKGROUND: Airway inflammation in asthma involves innate immune responses. Toll-like receptors (TLRs) and thymic stromal lymphopoietin (TSLP) are thought to be involved in airway inflammation, but their expression in asthmatics' both large and small airways has not been investigated. OBJECTIVE: To analyse the expression of TLR2, TLR3, TLR4 and TSLP in large and small airways of asthmatics and compare their expression in smoking and non-smoking asthmatics; to investigate whether TLR expression is associated with eosinophilic or neutrophilic airway inflammation and with Mycoplasma pneumoniae and Chlamydophila pneumoniae infection. METHODS: Using immunohistochemistry and image analysis, we investigated TLR2, TLR3, TLR4 and TSLP expression in large and small airways of 24 victims of fatal asthma, FA, (13 non-smokers, 11 smokers) and nine deceased control subjects (DCtrl). TLRs were also measured in 18 mild asthmatics (MA) and 12 healthy controls (HCtrl). M. pneumoniae and C. pneumoniae in autopsy lung tissue were analysed using real-time polymerase chain reaction. Airway eosinophils and neutrophils were measured in all subjects. RESULTS: Fatal asthma patients had higher TLR2 in the epithelial and outer layers of large and small airways compared with DCtrls. Smoking asthmatics had lower TLR2 levels in the inner and outer layers of the small airways than non-smoking asthmatics. TSLP was increased in the epithelial and outer layers of the large airways of FA. FA patients had greater TLR3 expression in the outer layer of large airways and greater TLR4 expression in the outer layer of small airways. Eosinophilic airway inflammation was associated with TLR expression in the epithelium of FA. No bacterial DNA was detected in FA or DCtrls. MA and HCtrls had only a small difference in TLR3 expression. CONCLUSIONS AND CLINICAL RELEVANCE: Increased expression of TLR 2, 3 and 4 and TSLP in fatal asthma may contribute to the acute inflammation surrounding asthma deaths.


Subject(s)
Asthma/mortality , Cytokines/metabolism , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 3/metabolism , Toll-Like Receptor 4/metabolism , Adult , Asthma/immunology , Female , Humans , Inflammation/immunology , Lung/immunology , Male , Middle Aged , Up-Regulation , Thymic Stromal Lymphopoietin
4.
Allergy ; 67(4): 552-9, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22229658

ABSTRACT

BACKGROUND: Altered deposition of extracellular matrix (ECM) in the airway smooth muscle (ASM) layer as observed in asthma may influence ASM mechanical properties. We hypothesized that ECM in ASM is associated with airway function in asthma. First, we investigated the difference in ECM expression in ASM between asthma and controls. Second, we examined whether ECM expression is associated with bronchoconstriction and bronchodilation in vivo. METHODS: Our cross-sectional study comprised 19 atopic mild asthma patients, 15 atopic and 12 nonatopic healthy subjects. Spirometry, methacholine responsiveness, deep-breath-induced bronchodilation (ΔR(rs) ) and bronchoscopy with endobronchial biopsies were performed. Positive staining of elastin, collagen I, III and IV, decorin, versican, fibronectin, laminin and tenascin in ASM was quantified as fractional area and mean density. Data were analysed using Pearson's or Spearman's correlation coefficient. RESULTS: Extracellular matrix expression in ASM was not different between asthma and controls. In asthmatics, fractional area and mean density of collagen I and III were correlated with methacholine dose-response slope and ΔR(rs) , respectively (r = 0.71, P < 0.01; r = 0.60, P = 0.02). Furthermore, ASM collagen III and laminin in asthma were correlated with FEV(1) reversibility (r = -0.65, P = 0.01; r = -0.54, P = 0.04). CONCLUSION: In asthma, ECM in ASM is related to the dynamics of airway function in the absence of differences in ECM expression between asthma and controls. This indicates that the ASM layer in its full composition is a major structural component in determining variable airways obstruction in asthma.


Subject(s)
Asthma/metabolism , Bronchi/metabolism , Extracellular Matrix/metabolism , Muscle, Smooth/metabolism , Adult , Asthma/pathology , Asthma/physiopathology , Bronchi/pathology , Bronchi/physiopathology , Bronchoscopy , Collagen/metabolism , Cross-Sectional Studies , Extracellular Matrix/pathology , Female , Humans , Immunohistochemistry , Male , Middle Aged , Muscle, Smooth/pathology , Respiratory Function Tests , Young Adult
5.
IEEE Trans Biomed Eng ; 58(9): 2633-9, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21708494

ABSTRACT

The detection of dysplasia in the gastrointestinal tract can be performed using optical microsensors based on thin-film optical filters and silicon photodiodes. This paper describes two optical microsensors that can be used for spectroscopy data collection in two different spectral bands (one in the violet/blue region and the other in the green region) for which two optical filters were designed and fabricated. An empirical analysis of gastrointestinal spectroscopic data using these specific spectral bands is performed. The obtained results show that it is possible to accurately differentiate dysplastic lesions from normal tissue, with a sensitivity and specificity of 77.8% and 97.6%, respectively. Therefore, the developed filters can be used as a tool to aid in diagnosis. The small size of the optical microsensors can enable, in the future, integration in endoscopic capsules.


Subject(s)
Diagnostic Techniques, Digestive System/instrumentation , Gastrointestinal Neoplasms/diagnosis , Microtechnology/instrumentation , Optics and Photonics/instrumentation , Spectrometry, Fluorescence/instrumentation , Algorithms , Diffusion , Humans , Sensitivity and Specificity , Silicon Dioxide , Titanium , Upper Gastrointestinal Tract/pathology
6.
Article in English | MEDLINE | ID: mdl-21096117

ABSTRACT

This paper describes the design of a miniature, cost-effective spectroscopy system for assessing tissue biochemical and morphological information using a few wavelengths. This instrument will integrate thin-film optical filters and silicon photodiodes, avoiding the use of a spectrograph and optical fibers. The components in the set-up design are described. The feasibility of using only 16 wavelengths to accurately extract tissue properties is confirmed on physical tissue models. Also, the suitable spectral performance of several optical filters for the selection of these wavelengths is demonstrated. The reduced size of this device will make possible its implementation in an endoscopic capsule.


Subject(s)
Capsule Endoscopes , Neoplasms/diagnosis , Photometry/instrumentation , Spectrometry, Fluorescence/instrumentation , Transducers , Early Diagnosis , Equipment Design , Equipment Failure Analysis , Humans , Miniaturization
7.
Rev Port Pneumol ; 16(6): 917-20; discussion 924, 2010.
Article in English, Portuguese | MEDLINE | ID: mdl-21067699

ABSTRACT

Hemoptysis is a common and alarming clinical problem. Acute massive hemoptysis is a life threatening condition. Different therapeutic strategies such as surgery, endovascular treatment and/or bronchoscopy have been applied. We report two cases of patients with severe hemoptysis who were treated by bronchoscopy guided topical hemostatic tamponade therapy with oxidized regenerated cellulose.


Subject(s)
Bronchoscopy , Cellulose, Oxidized , Hemoptysis/therapy , Hemostatic Techniques , Female , Humans , Male , Middle Aged , Severity of Illness Index
8.
Clin Exp Allergy ; 40(10): 1473-81, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20937062

ABSTRACT

BACKGROUND: IgE and its high-affinity receptor FcɛRI play an important role in allergy and asthma. The distribution of FcɛRI expression in the airways and within the airway wall, however, is largely unknown. OBJECTIVE: In this study, we aimed to map the distribution of FcɛRI in different layers of large airways (LA) and small airways (SA) in lung tissue from non-smoking and smoking patients who died of asthma [fatal asthma (FA)] and non-smoking controls (CTR). METHODS: Postmortem lung tissue from 24 cases of non-smoking FA, 13 smoking FA patients and from 19 subjects who died of non-pulmonary causes (CTR) was immunohistochemically stained for FcɛRI and AA1 (mast cell tryptase marker). The expression of these markers was analysed in inner, muscle, and outer layers of both LA and SA by image analysis. RESULTS: FcɛRI expression was higher in non-smoking and smoking FA compared with CTR in the inner and outer layer of SA. In the outer layer of LA, FcɛRI expression was higher in non-smoking FA compared with CTR. AA1 was higher in non-smoking FA compared with smoking FA and CTR in the outer layer of the SA, which was correlated with FcɛRI in this layer. CONCLUSION: Our results show that the expression of FcɛRI is higher in both LA and SA in FA compared with CTR. These differences are predominantly found in the outer layer where they can be attributed in part to the increased mast cell numbers. These results indicate an increased capacity to mount IgE-mediated reactions in FA, both in LA and SA.


Subject(s)
Asthma/immunology , Bronchi/immunology , Receptors, IgE/biosynthesis , Adult , Asthma/metabolism , Autopsy , Bronchi/metabolism , Female , Humans , Image Processing, Computer-Assisted , Immunohistochemistry , Male , Mast Cells/immunology , Middle Aged , Tryptases/biosynthesis
9.
Clin Exp Allergy ; 39(10): 1499-507, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19486035

ABSTRACT

BACKGROUND: To date, little information has been available about pulmonary artery pathology in asthma. The pulmonary artery supplies the distal parts of the lungs and likely represents a site of immunological reaction in allergic inflammation. The objective of this study was to describe the inflammatory cell phenotype of pulmonary artery adventitial inflammation in lung tissue from patients who died of asthma. METHODS: We quantified the different inflammatory cell types in the periarterial region of small pulmonary arteries in lung tissue from 22 patients who died of asthma [fatal asthma (FA)] and 10 control subjects. Using immunohistochemistry and image analysis, we quantified the cell density for T lymphocytes (CD3, CD4, CD8), B lymphocytes (CD20), eosinophils, mast cells (chymase and tryptase), and neutrophils in the adventitial layer of pulmonary arteries with a diameter smaller than 500 microm. RESULTS: Our data (median/interquartile range) demonstrated increased cell density of mast cells [FA=271.8 (148.7) cells/mm2; controls=177.0 (130.3) cells/mm2, P=0.026], eosinophils [FA=23.1 (58.6) cells/mm2; controls=0.0 (2.3) cells/mm2, P=0.012], and neutrophils [FA=50.4 (85.5) cells/mm2; controls=2.9 (30.5) cells/mm2, P=0.009] in the periarterial space in FA. No significant differences were found for B and T lymphocytes or CD4+ or CD8+ subsets. Chymase/tryptase positive (MCCT) mast cells predominated over tryptase (MCT) mast cells in the perivascular arterial space in both asthma patients and controls [MCCT/(MCCT+MCT)=0.91 (0-1) in FA and 0.75 (0-1) in controls, P=0.86]. CONCLUSIONS: Our results show that the adventitial layer of the pulmonary artery participates in the inflammatory process in FA, demonstrating increased infiltration of mast cells, eosinophils, and neutrophils, but not of T and B lymphocytes.


Subject(s)
Arteritis/metabolism , Asthma/metabolism , Lung/metabolism , Mast Cells/metabolism , Pulmonary Artery/metabolism , Adolescent , Adult , Aged , Antigens, CD/metabolism , Arteritis/mortality , Arteritis/pathology , Asthma/mortality , Asthma/pathology , Child , Chymases/metabolism , Female , Humans , Inflammation/metabolism , Inflammation/mortality , Inflammation/pathology , Leukocytes/metabolism , Leukocytes/pathology , Lung/blood supply , Lung/pathology , Male , Mast Cells/pathology , Middle Aged , Pulmonary Artery/pathology , Retrospective Studies , Tryptases/metabolism
10.
Fitoterapia ; 79(5): 356-60, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18538949

ABSTRACT

Leandra lacunosa, popularly known as "erva-do-jabuti", is used in Brazilian folkloric medicine for the treatment of diabetes mellitus. Based on this traditional indication, the aim of this work was to evaluate the hypoglycemic activity of the hydroalcoholic extract of L. lacunosa aerial parts (LLH) in normal and alloxan-induced diabetic rats. Chromatographic fractionation of LLH was also carried out by several techniques, affording isolation of the following major compounds: ursolic acid (1), kaempferol (2), luteolin (3), and quercetin (4). The oral administration of LLH (500 mg/kg) in normal rats caused a significant reduction of 24.7% (P<0.05) in the blood glucose levels after 2 h of treatment, while the administration of chlorpropamide (20 mg/kg, p.o.) led to a reduction of 40.2% (P<0.01). After oral administration of glucose (10 g/kg, p.o.), LLH (500 mg/kg, p.o.) significantly inhibited the increase in blood glucose levels compared with the negative control group. The oral treatment with LLH (500 mg/kg) in alloxan-induced diabetic rats significantly reduced the blood glucose levels in 47.8% after 4 h of treatment, while chlorpropamide resulted in a significant reduction of 71.7% in the 4th hour. Our results showed that LLH, displays hypoglycemic activity, which may be related to the effect of the major compounds identified in the crude extract. This study seems to provide biological evidence for the folkloric use of L. lacunosa in the treatment of diabetes mellitus.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Hypoglycemic Agents/pharmacology , Melastomataceae/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Alloxan , Animals , Blood Glucose/drug effects , Glucose Tolerance Test , Hypoglycemic Agents/chemistry , Male , Molecular Structure , Rats , Rats, Wistar
11.
Eur Respir J ; 32(1): 61-9, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18321931

ABSTRACT

There is an intimate relationship between the extracellular matrix (ECM) and smooth muscle cells within the airways. Few studies have comprehensively assessed the composition of different ECM components and its regulators within the airway smooth muscle (ASM) in asthma. With the aid of image analysis, the fractional areas of total collagen and elastic fibres were quantified within the ASM of 35 subjects with fatal asthma (FA) and compared with 10 nonfatal asthma (NFA) patients and 22 nonasthmatic control cases. Expression of collagen I and III, fibronectin, versican, matrix metalloproteinase (MMP)-1, -2, -9 and -12 and tissue inhibitor of metalloproteinase-1 and -2 was quantified within the ASM in 22 FA and 10 control cases. In the large airways of FA cases, the fractional area of elastic fibres within the ASM was increased compared with NFA and controls. Similarly, fibronectin, MMP-9 and MMP-12 were increased within the ASM in large airways of FA cases compared with controls. Elastic fibres were increased in small airways in FA only in comparison with NFA cases. There is altered extracellular matrix composition and a degradative environment within the airway smooth muscle in fatal asthma patients, which may have important consequences for the mechanical and synthetic functions of airway smooth muscle.


Subject(s)
Asthma/metabolism , Extracellular Matrix/metabolism , Matrix Metalloproteinases/metabolism , Muscle, Smooth/metabolism , Tissue Inhibitor of Metalloproteinases/metabolism , Adolescent , Adult , Asthma/pathology , Bronchi/metabolism , Bronchi/pathology , Case-Control Studies , Extracellular Matrix/pathology , Female , Humans , Male , Middle Aged , Muscle, Smooth/pathology
12.
Phytomedicine ; 10(6-7): 606-9, 2003.
Article in English | MEDLINE | ID: mdl-13678251

ABSTRACT

The analgesic effects of the hexane, methylene chloride and ethanol extracts of Miconia rubiginosa were evaluated in mice and rats using the acetic acid-induced writhing and hot plate tests. The extracts (100, 200 and 300 mg/kg body wt.) and indomethacin (5 mg/kg body wt.) produced a significant (p < 0.05 and p < 0.01) inhibition of acetic acid-induced abdominal writhing. These same extracts (200 mg/kg body wt.) showed a significant (p < 0.05) antinociceptive effect, lower than that produced by morphine (4 mg/kg body wt.). The fractionation of the methylene chloride extract yielded ursolic and oleanoic acids as the major compounds. Using only gas chromatography, it was possible to identify the following triterpenes in the hexane extract: alpha-amyrin, beta-amyrin, lupeol and beta-sitosterol.


Subject(s)
Analgesics/pharmacology , Melastomataceae , Pain/prevention & control , Phytotherapy , Plant Extracts/pharmacology , Acetic Acid , Analgesics/administration & dosage , Analgesics/therapeutic use , Animals , Dose-Response Relationship, Drug , Hot Temperature , Male , Mice , Pain/chemically induced , Pain Measurement/drug effects , Plant Components, Aerial , Plant Extracts/administration & dosage , Plant Extracts/therapeutic use , Rats
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