Search PubMed⌕ Search

Biomedical subjects

G Bonsignore

Publications and source records attributed to G Bonsignore.

At least 37 records · Page 2Linked to original sources
PubMed2001

Evaluation of the POLYMESAM system in the diagnosis of obstructive sleep apnea syndrome.

The reliability of a POLYMESAM (PM) instrument in the detection of ventilatory disorders and in the diagnosis of obstructive sleep apnea syndrome (OSAS) was evaluated in 50 subjects suspected for OSAS, simultaneously studied by polysomnography (PSG) in a sleep laboratory. Recordings were analysed by separate scorers, blinded to the results of the paired recording. The number of central (Ac), obstructive (Ao) or mixed apneas (Am), of hypopneas (H), and the total number of ventilatory disorders (AH) per hour of time in bed (TIB) calculated on the two recordings were significantly correlated. Bland and Altman analysis showed a good agreement between AH/TIB, Ac/TIB, Am/TIB and mean AH duration; a lower Ao/TIB at PM was mirrored by a higher H/TIB. Forty-two subjects had OSAS according to an apnea/hypopnea index (AHI) > or = 10 at PSG. Due to low sleep efficiency, AH/TIB was substantially lower than AHI. However an AH/TIB > or = 5 at PM showed a sensitivity of 100% and a specificity of 71.4%, while an AH/TIB > or = 10 showed a sensitivity of 95.2% and a specificity of 100%. In conclusion, PM proved reliable for recognition of the characteristics of ventilatory disorders and for diagnosis of OSAS.

Diagnosis, Differential↗
PubMed2000

Effects of gemcitabine on cell proliferation and apoptosis in non-small-cell lung cancer (NSCLC) cell lines.

We evaluated the antiproliferative and the proapoptotic ability of gemcitabine in three non-small-cell lung cancer (NSCLC) cell lines. NCI-H292 (mucoepidermoid carcinoma), NCI-CorL23 (large-cell carcinoma) and NCI-Colo699 (adenocarcinoma) cells were cultured with and without 0.5, 0.05 and 0.005 microM gemcitabine for 24, 48 and 72 h, respectively. Gemcitabine exerted a stronger and earlier antiproliferative and proapoptotic effect on H292 cells than on CorL23 or Colo699 cells. Fas receptor expression was increased in all three cell lines and was higher in Colo699 than in CorL23 cells. The incubation of NSCLC with anti-Fas agonistic monoclonal antibody (CH11) induced cell apoptosis in H292 cells, demonstrating that the Fas receptor was functionally active. Finally, gemcitabine and CH-11 exerted a synergistic effect on cell apoptosis in H292 cells. This study demonstrates that gemcitabine induces apoptosis in NSCLC and that this effect might be exerted by modulating functionally active Fas expression, and these effects of gemcitabine were stronger in H292 cells than in either CorL23 or Colo699 cells.

Antigens, Neoplasm↗
PubMed2000

Structural consequences of airway inflammation in asthma.

Asthma represents a chronic inflammatory process of the airways followed by healing, the end-result of which is an altered structure referred to as a remodeling of the airways. Repair usually involves 2 distinct processes: regeneration (which is the replacement of injured tissue by parenchymal cells of the same type) and replacement by connective tissue and its eventual maturation into scar tissue. In many instances both processes contribute to the healing response and inflammation. In asthma the processes of cell dedifferentiation, migration, differentiation, and maturation and connective tissue deposition can be followed either by complete or altered restitution of airway structure and function, the latter often seen as fibrosis and increase in smooth muscle and mucus gland mass. These features result in an increased resistance to airflow, particularly when there is bronchial contraction and bronchial hyperresponsiveness. The effect on airflow is compounded by the presence of increased mucous secretion and inflammatory exudate, which not only blocks the airway passages but also causes an increased surface tension that favors airway closure.

Animals↗
PubMed2000

Apoptosis and airway inflammation in asthma.

Asthma is a disease characterized by a chronic inflammation of the airways and by structural alterations of bronchial tissues, often referred to as airway remodelling. The development of chronic airway inflammation in asthma depends upon the continuous recruitment of inflammatory cells from the bloodstream towards the bronchial mucosa and by their subsequent activation. It is however increasingly accepted that mechanisms involved in the regulation of the survival and apoptosis of inflammatory cells may play a central role in the persistent inflammatory process characterizing this disease. Increased cellular recruitment and activation, enhanced cell survival and cell:cell interactions are therefore the key steps in the development of chronic airway inflammation in asthma, and represent the major causes for tissue damge, repair and remodelling.

Animals↗
PubMed2000

ICAM-1 and alpha3beta1 expression by bronchial epithelial cells and their in vitro modulation by inflammatory and anti-inflammatory mediators.

BACKGROUND: Adhesion molecules are involved in inflammatory and repair processes of the bronchial epithelium. ICAM-1 is mainly involved in inflammatory reactions, whereas integrins, such as alpha3beta1, are mainly involved in repair processes. METHODS: Using bronchial biopsies from 10 asthmatics and eight controls, we first evaluated by immunohistochemistry expression of alpha3beta1 and ICAM-1 in intact and damaged epithelium. Then, using the human pulmonary epithelial cell line WI-26 VA, we studied, by flow-cytometry, the modulation of ICAM-1 and alpha3beta1 expression, and, by ELISA, the release of fibronectin by proinflammatory cytokines, such as IL-5, and anti-inflammatory cytokines, such as IL-4, TGF-beta, and EGF. RESULTS: alpha3beta1 expression was slightly higher in asthma than in controls, as well as in damaged epithelium than in undamaged epithelium. ICAM-1 expression was higher in asthma than in controls, and similarly distributed in intact or damaged epithelium. In vitro, alpha3beta1 was significantly increased by TGF-beta, EGF, and IL-4, and significantly decreased by IL-5. Fibronectin release was significantly increased by TGF-beta and IL-4, unchanged by EGF, and slightly but significantly decreased by IL-5. ICAM-1 expression was significantly decreased by TGF-beta and IL-4, unchanged by EGF, and significantly increased by IL-5. CONCLUSIONS: These differences in adhesion molecule expression and fibronectin release may be important in epithelial cell inflammation and repair.

Adolescent↗
PubMed2000

Influence of sampling interval on the evaluation of nocturnal blood pressure in subjects with and without obstructive sleep apnoea.

Blood pressure (BP) variability during sleep is high in obstructive sleep apnoea syndrome (OSAS). How BP sampling interval affects the estimate of mean nocturnal BP in OSAS and control subjects was investigated. Nine subjects with apnoea/hypopnoea index (AHI) <5 and 18 OSAS patients with AHI >30 underwent nocturnal polysomnography with beat-by-beat BP monitoring. Mean nocturnal BP was evaluated averaging: a) all systolic (Ps) and diastolic (Pd) BP values; b) Ps and Pd sampled every 5, 10, 15, 20, and 30 min. The sampling starting point was repeatedly shifted, and several mean BP estimates for each sampling interval were obtained. Differences (deltaPs and deltaPd) between means obtained by sampling BP and by averaging all BP values were calculated. In both groups deltaPs and deltaPd scatter increased as sampling interval increased; their variance was always higher in OSAS subjects (p<0.001). Over 95% of deltaPs and deltaPd were <5% of the beat-by-beat mean values at all sampling intervals in controls, but this occurred only at sampling intervals < or =10 min in OSAS subjects. To conclude, for each blood pressure sampling time, a larger number of inaccurate nocturnal mean blood pressure estimates are obtained in obstructive sleep apnoea syndrome than in control subjects. Obstructive sleep apnoea syndrome subjects require more frequent blood pressure measurements to obtain a similar accuracy in nocturnal blood pressure evaluation.

Blood Pressure↗
PubMed2000

15-Lipoxygenase expression and 15(S)-hydroxyeicoisatetraenoic acid release and reincorporation in induced sputum of asthmatic subjects.

BACKGROUND: Recent evidence shows that 15(S)-hydroxy-eicoisatetraenoic acid (15[S]-HETE) can be released and rapidly reincorporated into cellular lipids. These mechanisms exert several immunoregulatory functions that may be relevant in airway inflammation. OBJECTIVE: Our purpose was to evaluate the levels of both soluble and cell-associated 15(S)-HETE and to examine 15-lipoxygenase (15-LO) messenger RNA (mRNA) expression in sputum samples obtained from 10 control and 18 asthmatic subjects. METHODS: Levels of 15(S)-HETE were measured by reverse-phase HPLC separation followed by RIA in supernatants and in cell membrane-extracted phospholipids after acid hydrolysis. 15-LO mRNA was evaluated by primed in situ hybridization (PRINS). Combined immunocytochemistry and PRINS was used to identify the phenotype of cells bearing 15-LO transcripts. RESULTS: Levels of both soluble and cell-associated 15(S)-HETE were higher in asthmatic than in control subjects (P <.0001). The percentage of cells expressing 15-LO mRNA was higher in asthmatic than in control subjects (P <.01). On double staining for specific cell-type markers and 15-LO mRNA, macrophages were the major source for 15-LO. CONCLUSION: This study shows that the induced sputum technique allows the evaluation of 15-LO activity and that soluble, cell-associated 15(S)-HETE and 15-LO levels are higher in asthmatic than in control subjects. In addition, this study indicates that, in induced sputum, airway macrophages are the major source of 15(S)-HETE in asthma.

Adult↗
PubMed2000

c-erbB-2 and episialin challenge host immune response by HLA class I expression in human non-small-cell lung cancer.

The role of major histocompatibility complex expression in cancer prognosis and pathogenesis is contradictory. The aim of the current study was to compare the expression of HLA class I molecules and of oncoproteins that may be sources of peptides presented by HLA class I antigens in non-small-cell lung cancer. For this purpose, the expression of HLA class I antigen and TAP-1 molecule (a transporter in the antigen-processing 1 transport protein) were studied with epidermal growth factor, receptor; c-erbB-2; episialin; wild-type and mutant p53; bcl-2 oncoprotein expression; and angiogenic factor expression (vascular endothelial growth factor and thymidine phosphorylase). The degree of lymphocytic stromal infiltration and of platelet-endothelial cell adhesion molecule-expressing lymphocytes was also studied. A strong association of c-erbB-2 and MUC1 (episialin) expression with HLA class I expression was observed (p = 0.005 and 0.009, respectively). Intense CD31-positive lymphocytic infiltration was also more frequent in HLA class I-positive cases (p = 0.05). Although there was no association of HLA class I expression with survival, loss of the HLA class I expression in MUC1 or c-erbB-2 overexpressing cases conferred a poorer clinical outcome (p = 0.04). Both c-erbB-2 and MUC1 are well-known targets of T-cell-mediated cytotoxicity and cell-cell or cell-matrix adhesion-regulating proteins. The authors provide evidence that the sequence of cell adhesion-disrupting oncoprotein expression, HLA class I induction, and enhanced epitope presentation followed by lymphocytic response is an important pathogenetic three-step sequence of events that define, in part, the clinical outcome in non-small-cell lung cancer.

Aged↗
PubMed2000

15(S)-HETE modulates LTB(4) production and neutrophil chemotaxis in chronic bronchitis.

We evaluated the levels of 15(S)-hydroxyeicosatetraenoic acid [15(S)-HETE] and the expression of 15-lipoxygenase (15-LO) mRNA in induced sputum obtained from 10 control and 15 chronic bronchitis subjects. 15(S)-HETE was evaluated by reverse phase high-performance liquid chromatography separation followed by specific RIA. 15-LO mRNA expression was determined by primed in situ labeling. The levels of both soluble and cell-associated 15(S)-HETE resulted significantly higher in chronic bronchitis than in control subjects. The percentage of cells expressing 15-LO mRNA was significantly higher in chronic bronchitis than in control subjects (P < 0.01). Double staining for specific cell type markers and 15-LO mRNA showed macrophages and neutrophils positive for 15-LO, whereas similar staining of peripheral blood neutrophils did not show evidence for 15-LO expression, suggesting that expression of 15-LO in neutrophils takes place on migration into the airways. Because 15(S)-HETE inversely correlated with the percentage of neutrophils in sputum of chronic bronchitis subjects, we studied the effect of 15(S)-HETE on leukotriene B(4) (LTB(4)) production in vitro and evaluated the concentration of LTB(4) in induced sputum and the contribution of LTB(4) to the chemotactic activity of induced sputum samples ex vivo. The results obtained indicate that macrophages and neutrophils present within the airways of chronic bronchitis subjects express 15-LO mRNA; increased basal levels of 15(S)-HETE may contribute to modulate, through the inhibition of 5-lipoxygenase metabolites production, neutrophil infiltration and airway inflammation associated with chronic bronchitis.

Adult↗
PubMed2000

Blood pressure and heart rate during periodic breathing while asleep at high altitude.

The ventilatory and arterial blood pressure (ABP) responses to isocapnic hypoxia during wakefulness progressively increased in normal subjects staying 4 wk at 5,050 m (Insalaco G, Romano S, Salvaggio A, Braghiroli A, Lanfranchi P, Patruno V, Donner CF, and Bonsignore G; J Appl Physiol 80: 1724-1730, 1996). In the same subjects (n = 5, age 28-34 yr) and expedition, nocturnal polysomnography with ABP and heart rate (HR) recordings were obtained during the 1st and 4th week to study the cardiovascular effects of phasic (i.e., periodic breathing-dependent) vs. tonic (i. e., acclimatization-dependent) hypoxia during sleep. Both ABP and HR fluctuated during non-rapid eye movement sleep periodic breathing. None of the subjects exhibited an ABP increase during the ventilatory phases that correlated with the lowest arterial oxygen saturation of the preceding pauses. Despite attenuation of hypoxemia, ABP and HR behaviors during sleep in the 4th wk were similar to those in the 1st wk. Because ABP during periodic breathing in the ventilatory phase increased similarly to the ABP response to progressive hypoxia during wakefulness, ABP variations during ventilatory phases may reflect ABP responsiveness to peripheral chemoreflex sensitivity rather than the absolute value of hypoxemia, suggesting a major tonic effect of hypoxia on cardiorespiratory control at high altitude.

Acclimatization↗
PubMed2000

Spontaneous gastroesophageal reflux and airway patency during the night in adult asthmatics.

Controversies still exist on the role of nighttime gastroesophageal reflux (GER) in precipitating nocturnal asthma. We tested the relationship between GER and nocturnal bronchoconstriction by continuously and simultaneously monitoring both respiratory resistances and esophageal pH in seven asthmatics with moderate to severe GER disease. Twenty-nine GER episodes were found during the study night lasting more than 5 min (LGER) and 72 not longer than 5 min (SGER). Both long (LGER) and short (SGER) gastroesophageal refluxes were able to maintain significantly higher lower respiratory resistances (RLR) at the resolution of each GER episode (RLR(e)) with respect to baseline values. RLR, expressed as the area under the RLR curve along each GER episode (AUCR(LR)) and as RLR(e), showed significant correlations with GER duration. Moreover, a significant correlation was found between RLR measured 10 min after GER resolution and GER duration during each episode. We conclude that GER itself is able to elicit nocturnal bronchoconstriction in asthmatics with moderate to severe GER disease and that bronchoconstriction severity and duration are related to GER duration.

Adult↗
PubMed2000

Glucocorticoid receptor alpha and beta in glucocorticoid dependent asthma.

Patients with glucocorticoid (GC)-dependent asthma present an ongoing inflammation of the airways despite chronic long-term treatment with oral GC. Interleukin (IL)-8 and granulocyte/macrophage colony-stimulating factor (GM-CSF) have been implicated in airway inflammation in severe asthma and their synthesis is normally repressed by GC. To further characterize the inflammatory process in GC-dependent asthma, we measured the release of IL-8 and GM-CSF by peripheral blood mononuclear cells (PBMC) of eight normal subjects, six untreated controlled asthmatics, six untreated uncontrolled asthmatics, and nine GC-dependent asthmatics. We show that PBMC from GC-dependent asthmatics released high amounts of these cytokines despite chronic in vivo exposure to GC (p < 0.001 versus normal subjects). In contrast, when untreated uncontrolled asthmatics were given a short course of oral GC, IL-8 and GM-CSF production was inhibited (p = 0.0078). Release of IL-8 and GM-CSF by PBMC of GC-dependent asthmatics was reduced after in vitro GC treatment (p < 0.002). We investigated whether the incapacity of GC to inhibit production of these cytokines in vivo was the result of a dysregulation of the glucocorticoid receptor (GR) in GC-dependent asthma. GRalpha and GRbeta are, respectively, the functional receptor and a putative dominant negative form of the receptor. Western blot and polymerase chain reaction (PCR) analyses indicated that GRalpha was expressed at similar level in all groups and was largely predominant over GRbeta. Thus, persistent release of IL-8 and GM-CSF in GC-dependent asthma is not associated with low expression of GRalpha or overexpression of GRbeta.

Adult↗
PubMed2000

Endogenous digitalislike factors in obstructive sleep apnea.

Recent studies have provided evidence that hypoxia may stimulate the release of endogenous digitalislike factors (EDLF). Obstructive sleep apnea (OSA) is characterized by intermittent hypoxia during sleep and may be associated with sympathetic activation and a high risk of developing hypertension. This study was designed to measure EDLF in the plasma of patients with OSA diagnosed by polysomnography, with patients being classified by the number of apneic-hypopneic episodes/h sleep (apnea-hypopnea index, AHI). Plasma was obtained in the morning from 8 male normotensive OSA patients (OSA-N) (AHI 70+/-6), 2 untreated hypertensive OSA patients (OSA-HT), and 11 age-matched healthy male controls (C). EDLFs of different hydrophobicities were separated from the same plasma sample by solid-state C18-cartridges with 25% acetonitrile (ACN) (EDLF-1) followed by 40% ACN (EDLF-2). This procedure recovered ouabain in the first fraction and digoxin and digoxigenin in the second. EDLF was quantified in pM ouabain-equivalents by a human placenta radioreceptor assay. EDLF-1 levels were similar for OSA-N and C (231+/-55 vs. 258+/-58), whereas EDLF-2 levels were increased in OSA-N (244+/-51 vs. 110+/-25 in C, p=0.02). Norepinephrine was increased in apneics. The two OSA-HT had EDLF and norepinephrine levels similar to OSA-N. These preliminary results suggest that OSA is associated with an increase in the more hydrophobic EDLF levels in both normotensive and hypertensive states. No significant increase was found for the less hydrophobic ouabain-like EDLF.

Adult↗
PubMed1999

The expression of basic fibroblast growth factor (bFGF) in tumor-associated stromal cells and vessels is inversely correlated with non-small cell lung cancer progression.

Tumor progression results from complex interactions between tumor and tumor-associated host tissue. Basic fibroblast growth factor (bFGF), via activation of its receptor, FGFR-1, has been postulated to be an important inducer of host stromal response and angiogenesis. To assess the putative role of tumor-associated stromal cells and vessels in tumor progression, we studied non-small cell lung cancer (NSCLC) from 84 patients, including 51 squamous cell carcinomas and 33 nonsquamous cell carcinomas, by immunohistochemical detection. bFGF and FGFR-1 immunoreactivity was observed in tumor and in tumor-associated stromal cells and vessels. The expression of bFGF and FGFR-1 in stromal cells was higher in squamous than in non-squamous cell carcinomas (respectively, P = .007 and P = .0004). We found that bFGF and FGFR-1 expression in tumor and tumor-associated stromal cells and vessels was directly correlated with host stromal response, as assessed by intratumoral extension of stroma, but not with angiogenic response, as assessed by microvessel count. Although FGFR-1 expression of tumor cells was directly correlated with T-stage (P = .03), bFGF expressions of tumor-associated stromal cells and vessels were inversely correlated with lymph node metastasis (respectively, P = .0001 and P = .0002) and advanced pathological stage (respectively, P = .03 and P = .01). These findings suggest that bFGF might mediate host stromal response in NSCLC and that the expression of bFGF in tumor-associated stromal cells and vessels might have an inhibitory role in NSCLC progression.

Aged↗
PubMed1999

Evaluation of apoptosis of eosinophils, macrophages, and T lymphocytes in mucosal biopsy specimens of patients with asthma and chronic bronchitis.

BACKGROUND: Apoptosis regulates inflammatory cell survival, and its reduction contributes to the chronicity of an inflammatory process. Apoptosis is controlled by suppressing or inducing genes, such as bcl-2 and p53, respectively. OBJECTIVE: We sought to assess apoptosis of eosinophils, macrophages, and T lymphocytes in bronchial biopsy specimens from asthmatic subjects and to examine its regulation by evaluating the expression of B-cell lymphoma leukemia-2 (Bcl-2) and P53 proteins. We also sought to explore the relationships between cell apoptosis and GM-CSF, a cytokine able to increase eosinophil and macrophage survival. METHODS: Apoptosis in eosinophils, macrophages, and T lymphocytes was evaluated in bronchial biopsy specimens obtained from 30 asthmatic subjects, 26 subjects with chronic bronchitis, and 15 control subjects by combining the terminal deoxynucleotidyl transferase-mediated dNTP nick end-labeling technique and immunohistochemistry. The expression of P53, Bcl-2, and GM-CSF was studied through immunohistochemistry by using specific mAbs. RESULTS: The number of apoptotic eosinophils and macrophages was lower in subjects with asthma than in those with chronic bronchitis (P <.007 and P <.001, respectively) and inversely correlated with the clinical severity of asthma (P <.001 and P <.002, respectively). Few T lymphocytes were apoptotic in all groups studied. In asthma GM-CSF+ cells correlated with the number of nonapoptotic eosinophils and macrophages (P =.0001) and with the severity of the disease (P <.003). In asthma Bcl-2+ cells were higher than in control subjects and subjects with chronic bronchitis (P <.002 and P <.015, respectively), they outnumbered P53+ cells, and they correlated with the number of T lymphocytes (P <.001) and with the severity of the disease (P <.003). CONCLUSION: Airway inflammation in asthma is associated with an enhanced survival of different cell types caused by reduced apoptosis.

Adult↗
PubMed1999

IL-4 and IgE-anti-IgE modulation of 15(S)-hydroxyeicosatetraenoic acid release by mononuclear phagocytes.

BACKGROUND: IL-4 modulates the synthesis of IgE, the expression of CD23, and the release of 15(S)-hydroxyeicosatetraenoic (15[S]-HETE). OBJECTIVE: We evaluated the release of 15(S)-HETE by IL-4-stimulated monocytes and verified whether the observed increase in 15(S)-HETE release after passive sensitization and anti-IgE challenge of IL-4-treated monocytes was secondary to an increased CD23 expression. METHODS: Human monocytes were incubated for 24, 48, and 72 hours with IL-4 (10 ng/mL) with or without an IgE-anti-IgE stimulation. We evaluated CD23 expression by immunocytochemistry and 15(S)-HETE release by HPLC and RIA. To prove that the increase in 15(S)-HETE release was due to the effect of IL-4 on CD23, we performed experiments with an anti-CD23 blocking mAb. RESULTS: CD23 expression and 15(S)-HETE release were significantly increased by IL-4, reaching a peak after 72 hours (P <.02). After passive sensitization with human IgE and anti-IgE challenge, IL-4-stimulated monocytes released higher amounts of 15(S)-HETE than IL-4-unstimulated monocytes (P <.02). Pretreatment with the anti-human B-cell CD23 MHM6 mAb caused a dose-dependent inhibition of 15(S)-HETE release. CONCLUSIONS: This study shows that immunologic challenge of IL-4-treated, passively sensitized monocytes results in a CD23-dependent additional increase of 15(S)-HETE release, indicating the presence of a synergistic effect of IL-4 on CD23 expression and 15(S)-HETE production.

Antibodies, Anti-Idiotypic↗
PubMed1999

Myocardial ischemia during sleep.

The role of sleep in the pathogenesis of coronary ischaemic events such as myocardial infarction, transient myocardial ischaemia, or cardiac sudden death, is unclear. This review will analyse the available data on the subject according to: (i) the autonomic and cardiovascular changes during sleep that may potentially favour myocardial ischaemia; (ii) the evidence of a circadian distribution of coronary events; and (iii) the factors possibly involved in the pathogenesis of nocturnal angina. Available data suggest that myocardial ischaemia may occur by different mechanisms in non-rapid eye movement (NREM) (decreased coronary perfusion pressure) and rapid eye movement (REM) sleep (increased myocardial oxygen demand). Coronary events show a major peak of occurrence between 6.00 a.m. and noon; however, the myocardial ischaemic threshold, defined as the heart rate value at which myocardial ischaemia develops, may be lower at night than during the daytime, suggesting an unexpectedly higher susceptibility to myocardial ischaemia during sleep than during wakefulness. These data warrant further study on the pathophysiology of coronary circulation during sleep. Finally, some evidence is available that sleep disordered breathing may precipitate nocturnal angina especially in REM sleep, through decreased arterial oxygen content secondary to hypoventilation or true apnoeas. More data are needed to better understand the effects of sleep on the coronary circulation, and to improve the therapeutic approach of nocturnal angina.

Journal Article↗