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Biomedical subjects

A Castagnaro

Publications and source records attributed to A Castagnaro.

16 recordsLinked to original sources

Vascular endothelial growth factor up-regulation and bronchial wall remodelling in asthma.

BACKGROUND: There is increasing in vitro evidence to support a role for vascular endothelial growth factor (VEGF), a major regulator of angiogenesis, as a mediator of fibrosis associated with neovascularization. OBJECTIVE: We tested the hypothesis that VEGF is involved both in increased airway mucosal vascularity and in the subepithelial fibrosis of asthmatic patients. METHODS: Bronchial biopsies were performed in 24 asthmatic patients and eight healthy controls. Immunostaining, using computerized image analysis, was performed using monoclonal antibodies against VEGF(+) cells, type IV collagen, to outline the basement membrane thickness, and tryptase and EG2, to identify mast cells and eosinophils, respectively. RESULTS: The counts of VEGF(+) cells (P<0.05), mast cells and EG2(+) cells (both P<0.01) were higher in asthmatics than in controls. The number of vessels, the vascular area in the lamina propria, and the basement membrane thickness were significantly higher in asthmatics than in healthy volunteers (P<0.01). Moreover, in asthmatic patients, the number of VEGF(+) cells was significantly related to the number of vessels (P<0.01), to mast cells (P<0.01) and to basement membrane thickness (P<0.01). A colocalization study also revealed that mast cells were a relevant cellular source of VEGF. High doses of inhaled fluticasone propionate significantly reduced VEGF(+) cells (P<0.05), vessel number (P<0.05), vascular area (P<0.05) and basement membrane thickness (P<0.05) in a subgroup of asthmatic patients. CONCLUSIONS: This study shows that VEGF, in addition to being involved in the vascular component of airway remodelling, may play a role in the thickening of the basement membrane in asthma.

Administration, Inhalation↗

Eosinophils in induced sputum from asymptomatic smokers with normal lung function.

Cigarette smoking is the dominant risk factor for chronic obstructive pulmonary disease (COPD). However, only 10-15% of smokers develop the disease and early changes within the airways are poorly defined. We aimed to compare cell profiles in induced sputum (IS) from asymptomatic smokers to that from healthy subjects, and to ascertain whether or not inflammatory cells in IS are related to lung function and smoking habit. We recruited 34 heavy, non-allergic asymptomatic smokers with normal lung function and 15 healthy volunteers, who performed lung function tests and IS by hypertonic saline (3%) solution. In smokers, significantcorrelation between pack-years and FEF25-75 (rs = -0.43, P < 0.02) was found. In IS, smokers had higher counts of macrophages (P < 0.01) and eosinophils (P < 0.02), when compared to those of healthy subjects. Additionally, eosinophils were found in IS of 14 out of 34 smokers, with eosinophils had a higher pack-years (31 +/- 25 vs. 13 +/- 10, P = 0.02) and lower FEF 25-75% value (78% +/- 34 vs. 100% +/- 23. P < 0.04). when compared to smokers without eosinophils. Additionally, on the basis of regression equations by stepwise multiple regression analysis, eosinophils were predicted by pack-years (r2 = 0.41). Our results showed that asymptomatic smokers have evidence of inflammatory cells in IS samples. In addition, we found thatthe degree of eosinophilic inflammation is related to early changes of lung function and can be predicted by smoking habit.

Adult↗

Relationship between outcome measures of six-minute walk test and baseline lung function in patients with interstitial lung disease.

BACKGROUND AND AIM OF THE WORK: In patients with interstitial lung disease (ILD), the six-minute walk test (6MWT) has been rarely used, and up till now, the relationship between outcome measures of the test and baseline lung function has not yet been examined. Therefore, we assessed walk distance, oxygen desaturation, and breathlessness perception during 6MWT, and their relationships to baseline lung function in patients with ILD. METHODS: Forty ILD patients with history of breathlessness during physical exertion performed a 6MWT following a standard protocol. Breathlessness perception during walk was assessed by visual analogue scale (VAS, in mm). RESULTS: The mean walk distance was 487 meters (range 271-689). Mean baseline oxygen saturation (Base SpO2, %) was 94% and was reduced during walk, either as mean oxygen saturation (Mean SpO2, 89%, p < 0.001) or as mean fall in oxygen saturation during walk (Fall SpO2, 5%). Furthermore, VAS significantly increased after walk (5 mm to 44 mm, p < 0.001). A close relationship of TLco and TLC to walk distance and Fall SpO2 was found (r = 0.45 and 0.42 and r = -0.75 and -0.64, respectively; p < 0.001, each). On the basis of regression equations by stepwise multiple regression analysis, walk distance was predicted by age and FVC (r2 = 0.50), Mean SpO2 by TLco and Base SpO2 (r2 = 0.80), and Fall SpO2 only by TLco (r2 = 0.57). Breathlessness perception was not reliably predicted by any assessed variables. CONCLUSIONS: We confirmed that 6MWT provides a global evaluation of sub-maximal exercise capacity in ILD patients. We also found that walk distance and oxygen desaturation, but not breathlessness perception during walk, are strictly related to baseline lung function.

Adult↗

The increased number of very late activation antigen-4-positive cells correlates with eosinophils and severity of disease in the induced sputum of asthmatic patients.

BACKGROUND: Lymphocyte function associate-1 (LFA-1), macrophage antigen-1 (Mac-1), and very late activation antigen-4 (VLA-4) are involved in the infiltration of leukocytes into the tissues. Experimental models of allergic inflammation suggest that VLA-4 could determine the selective recruitment of eosinophils into the inflamed airways. OBJECTIVE: Our purpose was to evaluate the involvement of integrins in eosinophil recruitment in asthma. METHODS: We evaluated by immunocytochemistry the expression of VLA-4, LFA-1, and Mac-1 and their relationship with inflammatory cells and severity of disease in the induced sputum of 20 mild to moderate atopic asthmatic subjects and in 8 healthy subjects. RESULTS: The number of VLA-4+ cells is increased in asthmatic patients and VLA-4 is mainly localized on eosinophils. Furthermore, VLA-4+ cells are significantly related to eosinophils. In contrast, LFA-1 and Mac-1 cellular expressions do not differ between asthmatic and control subjects and are not related to any specific cell type. Eosinophils and VLA-4+ cells are significantly higher in moderately compared with mildly asthmatic patients (P <.01, P <.05) and with healthy control subjects (P <.0005, P <.001). Eosinophils and VLA-4+ cells are also higher in mildly asthmatic patients compared with control subjects (P <.001, P <.005). CONCLUSION: This is the first report demonstrating, by a noninvasive method in humans, that VLA-4+ cells are increased and correlate with the eosinophils in the induced sputum of atopic patients with mild to moderate asthma and that VLA-4 expression is related to the severity of disease.

Adult↗

Isolation and purification of a 316 Da preformed compound from strawberry (Fragaria ananassa) leaves active against plant pathogens.

An antibiotic called fragarin showing activities against bacterial and fungal plant pathogens was isolated and purified by FPLC chromatography from the soluble fraction of strawberry leaves. The molecular weight value determined by mass spectrometry is 316 Da. Fragarin remains fully active after protease treatment or alkaline hydrolysis at 100 degrees C for 20 min. Biological and chemical analyses suggest that fragarin may be a new type of an antimicrobial preformed compound--phytoanticipin--and would constitute a primary non-specific barrier of strawberry defense.

Anti-Bacterial Agents↗

Induced sputum in patients with newly diagnosed sarcoidosis: comparison with bronchial wash and BAL.

OBJECTIVES: Sarcoidosis is characterized by a diffuse alveolar inflammatory process, although bronchial airways are often involved. This study compares the cellular profiles of induced sputum (IS), bronchial washing (BW), and BAL in newly diagnosed sarcoidosis patients to those in control subjects, and examines whether inflammatory cell counts from IS are correlated with inflammatory cell counts from BW and BAL in sarcoidosis patients. PATIENTS AND MEASUREMENTS: We recruited 15 untreated patients with stage I and II pulmonary sarcoidosis and 12 healthy volunteers. Sputum was induced with hypertonic saline solution in all individuals. Bronchoscopy was performed on a different occasion in all patients and in five control subjects. RESULTS: Mean lymphocyte counts in IS, BW, and BAL fluid from sarcoidosis patients were significantly higher than in control subjects (9.4% vs 3.8%, p < 0.05; 12.6% vs 3.9%, p < 0.05; 24.1% vs 2.6%, p < 0.05, respectively). Moreover, total cell count and percentage of epithelial cells in IS were significantly higher in sarcoidosis patients than in control subjects (p < 0.01 and p < 0.05, respectively). In sarcoidosis patients, comparison between different samples showed significantly higher percentages of macrophages in BW and BAL than in IS (p < 0.05 and p < 0.01, respectively), whereas the percentage of neutrophils was higher in IS compared with BW and BAL (p < 0.01 and p < 0.001, respectively). Finally, the percentage of lymphocytes in IS was significantly lower than that in BAL (p < 0.05) but not that in BW. CONCLUSIONS: We demonstrated that, compared with IS in healthy control subjects, IS in untreated pulmonary sarcoidosis patients contains more total cells, lymphocytes, and epithelial cells. Although the relative proportion of inflammatory cells in the three samples differed, lymphocyte counts in IS were high. This finding suggests that IS could be used as a valuable alternative to more conventional invasive techniques in clinical assessment of pulmonary sarcoidosis patients.

Administration, Inhalation↗

Effect of sputum induction on spirometric measurements and arterial oxygen saturation in asthmatic patients, smokers, and healthy subjects.

BACKGROUND: Sputum production induced by inhalation of hypertonic saline solution has been proposed as a technique to collect secretions and inflammatory cells from the airways of subjects with bronchial asthma or with a history of smoking. The aim of this study was to determine the effect of a sputum induction procedure on spirometric results and arterial oxygen saturation (SaO(2)) in asthmatic patients, smokers, and healthy subjects. METHODS: We recruited 14 subjects suffering from asthma (11 men and 3 women; age range, 18 to 49 years), 14 subjects with a history of smoking (5 men and 9 women; age range, 23 to 64 years), and 9 healthy volunteers (7 men and 2 women; age range, 28 to 54 years). To obtain a sample of induced sputum, all subjects inhaled a mist of 3% hypertonic saline solution nebulized for 5 min and repeated the cycle no more than four times. Asthmatic patients were pretreated with 200 microg salbutamol (inhaled). During sputum induction, the transcutaneous SaO(2) was continuously measured and baseline, fall, and the differences between baseline and fall SaO(2) were recorded. Additionally, we measured the duration of mild desaturation (change in SaO(2), < 4%) and of marked desaturation (change in SaO(2), > 5%) in each subject. Finally, baseline FEV(1) and changes in FEV(1) as a percentage of baseline values were recorded in all subjects. RESULTS: We found that baseline and fall SaO(2) values for the three groups were similar. However, in each group a significant mean change in SaO(2) was evident during sputum production (asthmatic patients, 6.0%; smokers, 5.3%; healthy subjects, 6.0%). Moreover, the mean durations of mild desaturation were 7 min, 21 s in asthma patients; 8 min, 24 s in smokers; and 7 min, 16 s in healthy subjects. Similarly, the durations of marked desaturation were 1 min, 25 s in asthmatic patients, 1 min, 19 s in smokers, and 1 min, 21 s in healthy subjects. The mean (+/- SD) fall in FEV(1) was not statistically different among the three groups (asthmatic patients, 1.36 +/- 5.6%; smokers, 7.58 +/- 11.76%; and healthy subjects, 0.05 +/- 9.6%). However, one smoker did experience excessive bronchoconstriction (fall in FEV(1), > 20%). CONCLUSIONS: This study demonstrated a significant and comparable fall in SaO(2) during sputum induction by inhalation of hypertonic saline solution in asthmatic patients, smokers, and healthy subjects. The results suggest that subjects who are hypoxemic before sputum induction require SaO(2) monitoring during the procedure.

Adolescent↗

Personality profiles and breathlessness perception in outpatients with different gradings of asthma.

We studied the relationship between personality profiles, breathlessness perception and clinical and functional features in 36 outpatient asthmatics (12 females; age range: 18-52 yr). Each patient underwent psychometric evaluation with Minnesota Multiphasic Personality Inventory (MMPI). Breathlessness perception was evaluated by Borg's scale during methacholine (M) challenge, and PS20 (the perception score obtained when FEV1 fell by 20%) was recorded. Baseline FEV1 values ranged from 70.0 to 126%. PC20 M values ranged from 0.05 to 31.7 mg/ml. According to a symptoms score system (0 to 12 points), 12 asthmatics were classified as mild, 12 as moderate, and 12 as moderate/severe. We did not find any specific personality profile in asthmatic patients. Sixteen asthmatics had at least one MMPI subscale score indicative of psychological disturbances. We found a significant trend from mild to moderate and moderate/severe asthmatics (p < 0.015), when the number of asthmatics with subscale scores indicative of psychological disturbances was compared to that of asthmatics with normal scores. Moreover, we found that the asthmatics with scores indicative of hypochondriasis showed a significant trend from mild to moderate and moderate/severe asthma (p < 0.015). Furthermore, in all asthmatic patients, hypochondriasis scores were positively correlated to asthma severity score (p < 0.02). PS20 values ranged from 0.1 to 8.1. Twelve asthmatics were hypoperceivers (PS20 < or = 1) and four were hyperperceivers (PS20 > or = 5). We observed a significant trend from mild to moderate and moderate/severe asthmatics (p < 0.025) when we compared the number of hypoperceivers to that of normoperceivers. In conclusion, we found that in outpatients with different grading of asthma, severity of disease is linked to psychological disturbances and poor perception of breathlessness, additionally, hypochondriasis was related to disease severity in all patients.

Adolescent↗

Specific localization of the respiratory alternative oxidase in meristematic and xylematic tissues from developing soybean roots and hypocotyls.

We used tissue printing and specific immunostaining to examine the localization of the alternative oxidase (AOX) protein in correlation with measurements of AOX capacity. Selected root and hypocotyl regions were analyzed during the first 14 d of growth. It is shown that AOX protein is localized in the apical meristem and in developing xylem. The temporal pattern of expression is coincident with the evolution of AOX capacity. Data suggest that AOX expression is linked to xylem differentiation. Since heat is a major product of the alternative pathway, we speculate that thermogenesis is implicated in morphogenesis.

Gene Expression Regulation, Developmental↗

A fatty-acid-binding protein from wheat kernels.

A protein of about 7 kDa (W-FABP) has been isolated from mature wheat kernels by H2O extraction and gel filtration of the extract, followed by two steps of high-performance liquid chromatography. The N-terminal amino acid-sequence has been determined up to the 28th residue and found to be identical (except for positions 4 and 5) to that deduced from a barley cDNA (EMBL X15257), which had been improperly classified as a non-specific lipid transfer protein (LTP2). Similarly with LTPs, W-FABP does bind fatty acids, but in contrast, it is not significantly homologous to LTPs, it is not recognized by LTP antibodies, it has a more acidic isoelectric point (pH < 6.8 vs. pH > 9.6), and it does not show antibiotic properties.

Amino Acid Sequence↗

Sharp divergence between wheat and barley at loci encoding novel members of the trypsin/alpha-amylase inhibitors family.

Amino acid sequences for three members (CMx1, CMx2, and CMx3) of a new subfamily of trypsin/alpha-amylase inhibitors in wheat have been deduced from the nucleotide sequences of the corresponding cDNAs. A cDNA clone encoding CMx1 was selected from a wheat developing endosperm library using a probe that encoded barley trypsin inhibitor BTI-CMe at low stringency. Sequences corresponding to CMx2 and CMx3 were obtained from cDNA amplified by the polymerase chain reaction. The three CMx sequences contain a premature stop codon after 363 nt, as well as a second stop codon at the same position as in BTI-CMe (nt 439-441). Southern analysis of DNAs from diploid, tetraploid, and hexaploid wheats, as well as from aneuploid lines, indicate that there is a single CMx locus in each of the three genomes of hexaploid wheat, respectively associated with chromosomal arms 4AS, 4BS, and 4DL. These genes are expressed early during endosperm development and not expressed at detectable levels in other tissues. Evolutionary implications are discussed.

Amino Acid Sequence↗

The barley alpha-thionin promoter is rich in negative regulatory motifs and directs tissue-specific expression of a reporter gene in tobacco.

The promoter of the barley alpha-thionin gene (1.6 kb) fused to the beta-glucuronidase (GUS) gene directs temporally-controlled, tissue-specific expression in the endosperm of transgenic tobacco. The nucleotide sequence of this promoter shows negative regulatory motifs which have been functionally analyzed in other genes.

Antimicrobial Cationic Peptides↗

Extreme divergence of a novel wheat thionin generated by a mutational burst specifically affecting the mature protein domain of the precursor.

A new type of neutral thionin (type V), specifically expressed in developing wheat endosperm, has been found to be encoded by a set of single-copy genes located in the long arms of chromosomes 1A, 1B and 1D, within less than 10,000 base-pairs of those corresponding to the highly basic type-I thionins. Divergence between types I and V has occurred through a process of accelerated evolution that has affected the amino acid sequence of the mature thionin but not the precursor domains corresponding to the N-terminal signal peptide and the long C-terminal acidic peptide. This process involved a deletion and a non-synonymous nucleotide substitution rate equal to the synonymous rate in the thionin sequence.

Amino Acid Sequence↗

Extreme variations in the ratios of non-synonymous to synonymous nucleotide substitution rates in signal peptide evolution.

Nucleotide sequences encoding signal peptides from the precursors of alpha-amylase/trypsin inhibitors from cereals are homologous to those corresponding to the precursors of thaumatin II and of plastocyanins. Non-synonymous (KA) and synonymous (KS) rates of nucleotide substitutions have been calculated for all possible binary combinations. Extreme variation in KA/KS ratios has been observed; from the 0.167 average found within the plastocyanin family to an average of 1.90 calculated for the inhibitors/thaumatin II transition. A similar calculation has been carried out for the signal peptide sequences of thionins, which are unrelated to those of the alpha-amylase/trypsin inhibitor family, and an average KA/KS of 0.12 has been obtained. This variation can be largely explained in terms of an empirical index of stability related to amino acid composition and seems to be independent of functional constraints.

Amino Acid Sequence↗