Budesonide/glycopyrronium/formoterol fumarate triple therapy prevents pulmonary hypertension in a COPD mouse model via NFκB inactivation.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a health problem that results in death, commonly due to the development of pulmonary hypertension (PH). Here, by utilizing a mouse model of intratracheal elastase-induced emphysema that presents three different phases of COPD, we sought to observe whether budesonide/glycopyrronium/formoterol fumarate (BGF) triple therapy could prevent COPD-PH in addition to ameliorating COPD progression. METHODS: We utilized intratracheal elastase-induced emphysema mouse model and performed experiments in three phases illustrating COPD progression: inflammatory (1 day post-elastase), emphysema (3 weeks post-elastase) and PH (4 weeks post-elastase), while treatments of BGF and controls (vehicle, one-drug, and two-drug combinations) were started in prior to elastase instillation (inflammatory phase), at day 7 (emphysema), or at day 14 (PH phase). Phenotype analyses were performed in each phase. In vitro, A549 cells or isolated mouse lung endothelial cells (MLEC) were treated with TNFα with/without BGF treatment to analyze NFκB signaling and cytokine expression changes. RESULTS: We observed significant reductions in the proinflammatory phenotype observed in the lungs and bronchoalveolar lavage fluid (BALF) 1 day after elastase administration in mice treated with BGF compared with that in mice administered elastase alone (BALF neutrophil percentage, p = 0.0011 for PBS/Vehicle vs. PBS/Elastase, p = 0.0161 for PBS/Elastase vs. BGF). In contrast, only BGF treatment significantly ameliorated the elastase-induced emphysematous lung structure and desaturation after three weeks of elastase instillation (mean linear intercept, p = 0.0156 for PBS/Vehicle vs. PBS/Elastase, p = 0.0274 for PBS/Elastase vs. BGF). Furthermore, BGF treatment prevented COPD-PH development, as shown by improvements in the hemodynamic and histological phenotypes four weeks after elastase treatment (right ventricular systolic pressure, p = 0.0062 for PBS/Vehicle vs. PBS/Elastase, p = 0.027 for PBS/Elastase vs. BGF). Molecularly, BGF acts by inhibiting NFκB-p65 phosphorylation and subsequently decreasing the mRNA expression of proinflammatory cytokines in both alveolar epithelial and pulmonary endothelial cells. CONCLUSION: Our results collectively showed that BGF treatment could prevent PH in addition to ameliorating COPD progression via the inhibition of inflammatory NFκB signaling.

Antimicrobial resistance, virulence factors, and genotypes of Pseudomonas aeruginosa clinical isolates from Gorgan, northern Iran.

Pseudomonas aeruginosa is an important nosocomial pathogen with a capacity of resistance to multiple antibiotics and production of various extracellular and cell-associated virulence factors that clearly contribute to its pathogenicity. The objective of this study was to investigate the antibiotic susceptibility, virulence factors, and clonal relationship among clinical isolates of P. aeruginosa. Different clinical specimens from hospitalized patients were investigated for P. aeruginosa. Susceptibility of the isolates was evaluated by disc diffusion and broth microdilution methods, as described by the Clinical and Laboratory Standards Institute (CLSI) guideline. A total of 97 P. aeruginosa isolates were recovered from clinical specimens. The percentage of isolates resistant to antimicrobials was imipenem 25.77%, meropenem 15.46%, gentamicin 16.49%, tobramycin 15.46%, amikacin 16.49%, ciprofloxacin 20.61%, levofloxacin 24.74, ceftazidime 20.61%, piperacillin 15.46%, piperacillin/tazobactam 12.37%, colistin 9.27%, and polymyxin B 11.34%. Of isolates, 87.62% possessed ß-hemolytic activity, 78.35% lecithinase, 59.8% elastase, 37.11% DNase, and 28.86% twitching motility. The frequency of virulence genes in isolates was lasB 82.47%, plcH 82.47%, exoA 58.76%, exoS 56.7%, and pilA 10.3%. ERIC-PCR typing clustered P. aeruginosa isolates to 19 common types (CT1-CT19) containing isolates from different hospitals and 43 single types (ST1-ST43). Colistin and polymyxin B were the most effective agents against the majority of P. aeruginosa isolates, emphasizing the effort to maintain their antibacterial activity as last-line therapy. The frequency of some virulence factors and genes was noticeably high, which is alarming. In addition, more effective strategies and surveillance are necessary to confine and prevent the inter-hospital and/or intra-hospital dissemination of P. aeruginosa between therapeutic centers.

Arteriovenous fistula patency in the 3 years following vonapanitase and placebo treatment.

OBJECTIVE: This study explored the long-term outcomes of arteriovenous fistulas treated with vonapanitase (recombinant human elastase) at the time of surgical creation. METHODS: This was a randomized, double-blind, placebo-controlled trial of 151 patients undergoing radiocephalic or brachiocephalic arteriovenous fistula creation who were randomized equally to placebo, vonapanitase 10 µg, or vonapanitase 30 µg. The results after 1 year of follow-up were previously reported. The current analysis occurred when the last patient treated was observed for 3 years. For the current analysis, the primary end point was primary patency; the secondary end points included secondary patency, use of the fistula for hemodialysis, and rate of procedures to restore or to maintain patency. RESULTS: There was no significant difference in the risk of primary patency loss with vonapanitase 10 µg or 30 µg vs placebo. When seven initial patency loss events related to cephalic arch and central vein balloon angioplasty were excluded, the risk of patency loss was reduced with vonapanitase overall (hazard ratio [HR], 0.63; P = .049) and 30 µg (HR, 0.51; P = .03). In patients with radiocephalic fistulas (n = 67), the risks of primary and secondary patency loss were reduced with 30 µg (HR, 0.37 [P = .02] and 0.24 [P = .046], respectively). The rate of procedures to restore or to maintain fistula patency was reduced with 30 µg vs placebo (0.23 vs 0.72 procedure days/patient/year; P = .03) and also reduced in patients with radiocephalic fistulas with 30 µg vs placebo (0.17 vs 0.85 procedure days/patient/year; P = .048). CONCLUSIONS: In this study, vonapanitase did not significantly improve primary patency in the primary analysis but did significantly improve primary patency in an analysis that excluded patency loss due to cephalic arch and central vein balloon angioplasty. In patients with radiocephalic fistulas, 30 µg significantly improved primary and secondary patency. Vonapanitase 30 µg decreased the rate of procedures to restore or to maintain patency in the analysis that included all patients and in the subset with radiocephalic fistulas.

The virulence of Dichelobacter nodosus, measured by the elastase test, is an important predictor for virulent footrot diagnosis in New South Wales sheep flocks.

Ovine footrot is a contagious bacterial disease that causes foot lesions, and depending on the virulence of the causative strains, may lead to severe underrunning of the hoof and lameness. Virulent footrot can be identified, treated and controlled more effectively than less virulent benign forms. The in vitro elastase test for virulence of the causative bacteria, Dichelobacter nodosus, has been used to support clinical diagnosis. However, not all laboratory-designated virulent D. nodosus strains cause clinical signs of virulent footrot. This study evaluated retrospectively how well the elastase test supported clinical footrot diagnosis in 150 sheep flocks examined for suspect footrot in New South Wales between August 2020 and December 2021. Flocks were included if measures of clinical disease, environmental conditions and the virulence of D. nodosus isolates were available. Variation in the elastase activity result between D. nodosus isolated from the same flock made bacterial virulence hard to interpret, but calculating the mean elastase rate for all isolates from the same flock made correlations between bacterial virulence and flock footrot diagnosis possible. Simplifying bacterial virulence into whether there were any elastase-positive D. nodosus isolates before 12 days increased the predictive value of elastase results for virulent diagnosis, compared with using the first day that any isolate was elastase positive or the percentage of elastase-positive isolates by 12 days, but not all clinically virulent flocks had isolates with elastase activity before 12 days. Logistic regression models were fitted to identify the minimum number of predictors for virulent footrot diagnosis, with models suggesting that virulent footrot diagnosis was best predicted by adding the elastase test result and environmental conditions to the prevalence of severe foot lesions (score 4 and 5). However, performing the same analysis with different breeds, ages of sheep and seasons might highlight other factors important in the diagnosis of virulent footrot.

The clinical and laboratory impact of reporting faecal elastase-1 in watery stool samples.

BACKGROUND: Low faecal elastase-1 (FE-1) results are suggestive of pancreatic insufficiency, but watery diarrhoea may lead to falsely low results. METHODS: FE-1 results reported on watery samples over a three-year period were reviewed. Results in watery samples were compared to those from a formed sample. The follow-up of patients in whom an FE-1 result ≤199 ug/g stool (Schebo ELISA) was reported on a watery sample was also reviewed. RESULTS: In total, 288 watery samples were identified. All results (19/19) ≥200 ug/g in watery samples were also ≥200 ug/g when measured in a formed sample from the same patient. There were 41 results ≤199 ug/g in watery samples, of which 29 (71%) were ≥200 ug/g when measured in a formed sample. Thirty-seven patients with a single FE-1 value ≤199 ug/g from a watery sample were followed up. Pancreatic Enzyme Replacement Therapy (PERT) was commenced in 15 patients. This was inappropriate in at least one patient. Reporting practice was subsequently changed to not report FE-1 values ≤199 ug/g in watery samples. This change was assessed after 12 months. Repeat samples were received from 15/56 (27%) of patients. Overall, 10/15 (67%) of samples were ≥200 ug/g on repeat. PERT was not commenced inappropriately in any of these patients. CONCLUSIONS: There is value in measuring FE-1 in watery samples, as 144/288 (50%) of watery samples analysed were ≥200 ug/g, enabling a diagnosis of exocrine pancreatic insufficiency to be excluded. Not reporting FE-1 values ≤199 ug/g in a first-time watery stool samples appears clinically safe and has potentially reduced inappropriate diagnoses and prescribing.

Therapeutic Potential of Antimicrobial Peptide PN5 against Multidrug-Resistant E. coli and Anti-Inflammatory Activity in a Septic Mouse Model.

Antibiotic-resistant bacteria have become a public health problem. Thus, antimicrobial peptides (AMPs) have been evaluated as substitutes for antibiotics. Herein, we investigated PN5 derived from Pinus densiflora (pine needle). PN5 exhibited antimicrobial activity without causing cytotoxic effects. Based on these results, we examined the mode of action of PN5 against Gram-negative and -positive bacteria. PN5 exhibited membrane permeabilization ability, had antimicrobial stability in the presence of elastase, a proteolytic enzyme, and did not induce resistance in bacteria. Bacterial lipopolysaccharide (LPS) induces an inflammatory response in RAW 264.7 macrophages. PN5 suppressed proinflammatory cytokines mediated by NF-κB and mitogen-activated protein kinase signaling. In C57BL/6J mice treated with LPS and d-galactosamine, PN5 exhibited anti-inflammatory activity in inflamed mouse livers. Our results indicate that PN5 has antimicrobial and anti-inflammatory activities and thus may be useful as an antimicrobial agent to treat septic shock caused by multidrug-resistant (MDR) Escherichia coli without causing further resistance. IMPORTANCE Antibiotic-resistant bacteria are a global health concern. There is no effective treatment for antibiotic-resistant bacteria, and new alternatives are being suggested. The present study found antibacterial and anti-inflammatory activities of PN5 derived from Pinus densiflora (pine needle), and further investigated the therapeutic effect in a mouse septic model. As a mechanism of antibacterial activity, PN5 exhibited the membrane permeabilization ability of the toroidal model, and treated strains did not develop drug resistance during serial passages. PN5 showed immunomodulatory properties of neutralizing LPS in a mouse septic model. These results indicate that PN5 could be a new and promising therapeutic agent for bacterial infectious disease caused by antibiotic-resistant strains.

Reduced expression of virulence factors in multidrug-resistant Pseudomonas aeruginosa strains.

MDR Pseudomonas aeruginosa strains are isolated from clinical specimens with increasing frequency. It seems that acquiring genes which determine antibiotic resistance usually comes at a biological cost of impaired bacterial physiology. There is no information on investigations comparing phenotypic differences in MDR and MDS P. aeruginosa strains in literature. The study included 150 clinical P. aeruginosa isolates (75 classified as MDS and 75 as MDR). PFGE analysis revealed five pairs of identical isolates in the group of MDR strains and the results obtained for these strains were not included in the statistical analyses. MDR strains adhered to polystyrene to a lesser extent than MDS strains. The growth rate in the liquid medium was significantly lower for MDR strains. Detectable amounts of alginate were present in the culture supernatants of seven MDS and six MDR strains. The MDR P. aeruginosa strains which were investigated produced significantly lower amounts of extracellular material binding Congo Red, lower lipolytic, elastase, LasA protease, phospholipase C activity and pyocyanin quantity in culture supernatants when compared with MDS strains. No significant differences were observed between MDR and MDS strains in proteolytic activity. In conclusion, the MDR P. aeruginosa strains have impaired virulence when compared to MDS strains.

The investigation and management of pancreatic exocrine insufficiency: A retrospective cohort study.

Pancreatic exocrine insufficiency (PEI) is associated with significant gastrointestinal symptoms, but is readily treated by pancreatic enzyme replacement therapy (PERT). We reviewed our current practice and examined the factors that predict repeating a positive faecal elastase-1 (FE1; <200 µg/g), the repeat FE1 being normal, initiation of PERT and clinical response to treatment. A single-centre retrospective cohort study was conducted. Outpatients with FE1 <200 µg/g between 2012 and 2018 were included. Logistic regression was used to explore the associations with each outcome, with statistical adjustment for confounders. Two-hundred and ten patients were included; 28.1% of patients had their FE1 repeated, 47.5% of whom had a normal repeat result. Patients with initial FE1 <15 µg/g were unlikely to be reclassified on repeat testing. Patients with a confirmatory low FE1, abnormal pancreatic imaging or abnormal nutrition blood tests were more likely to be started on PERT (all p<0.05). Patients with abnormal pancreatic imaging were 10 times more likely to respond to PERT (odds ratio 10.70; 95% confidence interval 1.62-70.70; p=0.01). Augmenting clinical judgement with pancreatic imaging and repeat FE1 testing could improve the rate of PERT prescription and inform the approach to non-response, particularly in cases where there is diagnostic doubt.

Primary Cilia Deficiency Induces Intracranial Aneurysm.

BACKGROUND: Intracranial aneurysm (IA) rupture is life-threatening. However, the mechanisms underlying IA initiation, progression, and rupture remain poorly understood. In the present study, we examined the role of primary cilia in IA development. RESULTS: IA was experimentally induced in mice with elastase and angiotensin II treatment. The number of cells with primary cilia was determined in both IA and peri-IA regions. The role of primary cilia in IA development was assessed through knocking out or manipulating the expression of important components of primary cilia. Finally the role of primary cilia in human IA patients was studied. In the mice model of IA, the primary cilia number was significantly decreased in the IA region. Knocking out Polycystin 1, Polycystin 2, and Intraflagellar Transport 88 in mice would increase the susceptibility of mice to IA development. The IA development could be modulated through manipulating the pathways that regulate primary cilia dynamics. And chemical screening showed that the three factors (PHA 680623, Rapamycin, and Forskolin) could efficiently suppress the IA development. Finally, we demonstrated that the primary cilia deficiency in IA development is conserved in humans. And IA patients had a higher frequency of gene mutations which are related to primary cilia regulation. CONCLUSION: Our study provides an important support for the role of primary cilia in the development of IA. The primary cilia stabilizing chemicals might be useful for preventing IA development.

Animal models of arterial stiffness.

Animal models of large artery wall stiffness fall into two categories: firstly those that slowly develop multifactorial vascular dysfunction spontaneously, such as the ageing rat. The second type of model consists of those in which a specific pathology is induced by surgical, chemical, or genetic means. Such models are based on a short-term, highly traumatic insult to the arterial wall of a young animal and its acute reaction to such insult. This is very different from the human situation in which changes in wall stiffness arise from the long-term accumulation of relatively minor episodes of vascular insult in the vulnerable elderly.

Pulmonary Emphysema Cross-Linking with Pulmonary Fibrosis and Vice Versa: a Non-usual Experimental Intervention with Elastase and Bleomycin.

Elastase (PPE) is usually used for emphysema models, whereas bleomycin (BLM) is used for fibrosis models. The aim of this study was to investigate the effect of BLM in PPE-induced emphysema, as well as the effect of PPE in BLM-induced fibrosis. C57BL/6 mice were divided into five groups: control, PPE, BLM, PPE + BLM, and BLM + PPE. Mice received saline, PPE (3 U/mouse), or BLM (20 U/kg) by intranasal instillation. Mice from the BLM and BLM + PPE groups received BLM on day 0 and saline or PPE on day 21, respectively. Those in the PPE and PPE + BLM groups received PPE on day 0 and saline or BLM on day 21, respectively. Mice were euthanized on day 42. We performed histology, morphometry in lung sections and ELISA, zymography and western blotting in BAL samples or lung homogenates. In the lungs of PPE + BLM and BLM + PPE groups, we observed inflammation, oxidative stress and expression of MMP-2 and MMP-9. The alveolar enlargement was reduced in the PPE + BLM group, suggesting that the BLM could participate in the alveolar remodeling process. The significance of this result supports future therapeutic approaches targeting extracellular-matrix deposition in patients with emphysema as a way to repair the enlargement of alveoli and airspaces.

Lung structure and function in elastase-treated rats: A follow-up study.

Structural and functional longitudinal alterations of the lungs were followed in an emphysema model. Rats were treated with porcine pancreatic elastase (PPE, n=21) or saline (controls, C, n=19). Before the treatment and 3, 10, 21 and 105 days thereafter, absolute lung volumes (FRC, TLC and RV) and tissue mechanical parameters (elastance: H; damping: G) were determined. At 3, 21 and 105 days the lungs were fixed in subgroups of rats. From histological samples the equivalent diameter of airspaces (Dalv), elastin (Mec) and collagen densities were assessed. In the PPE group, FRC and RV were higher from 3 days after treatment compared to controls (p<0.001), while TLC exhibited a delayed increase. H and G decreased in the PPE group throughout the study (p<0.001). Higher Mec (p<0.001) and late-phase inflammation were observed at 105 days. We conclude that during the progression of emphysema, septal failures increase Dalv which decreases H; this reveals a strong structure-function relationship.

The effect of pancreatic elastase on diabetic nephropathy.

Pancreatic elastase has been shown to inhibit the thickening of glomerular basement membranes in experimental diabetic animals. We explored the clinical significance of the prolonged administration of pancreatic elastase on diabetic nephropathy, in patients whose blood glucose levels and blood pressure were controlled. Pancreatic elastase was administered for 12 months. Body weight levels, blood glucose levels, HbA1c values and blood pressure remained unchanged. Administration of 10,800 U of pancreatic elastase caused a significant decrease in albuminuria (before administration, 512.4 +/- 79.8 mg/g creatinine vs. 12 months after administration, 284.1 +/- 61.9 mg/g creatinine, P < 0.01, n = 28). In the contrast group (n = 18), no significant changes in albuminuria were observed after administration of 300 mg of dilazep dihydrochloride. Serum levels of creatinine and urinary levels of NAG and beta 2 MG were not affected by pancreatic elastase. The present study indicates a significant inhibitory effect of pancreatic elastase on increased albuminuria in diabetic patients.

An experimental study on prevention of postlaminectomy scar formation by the use of new materials.

An experimental study was performed to investigate the prevention of scar formation after lumbar laminectomy, using Elastase and the new polylactic acid (PLA) membrane containing Elastase. The experimental animals consisted of four groups: control group, E group (using intravenous administration of Elastase), P group (covering the laminectomy defect with PLA membrane), and P-E group (covering the laminectomy defect with "PLA" + Elastase" membrane). The animals were killed at varying intervals (2-12 weeks) and changes in the lumbar spines were evaluated histologically. Scar formation was suppressed most significantly in the P-E group, followed in order by the E group, the P group, and the controls.

Effect of pancreatopeptidase E (elastase) on the suppression of intimal fibrous proliferation after arterial reconstruction in high cholesterol fed rabbits.

The purpose of this study was to investigate the effect of pancreatopeptidase E (Elastase) administration on the healing of anastomosed arteries. A segment of infrarenal aorta was resected and reanastomosed in rabbits. In the control group, rabbits were fed commercial chow (ORC 4). In the cholesterol group, rabbits were fed a diet of 1% cholesterol added to ORC 4. In the Elastase group, rabbits were fed the same diet as the cholesterol group but received intraabdominal injections of Elastase. The rabbits were kept for 4 months and the abdominal aorta was retrieved for examination. All anastomosed aortas were patent. The cholesterol group developed aneurysmal dilatation in one and stenosis of the anastomosed sites due to hypergranulation in the remaining rabbits. Neither aneurysmal nor stenotic changes were detected in the other groups. We concluded that the administration of Elastase suppressed cholesterol induced atherosclerotic changes at the anastomotic sites in these animals.

Efficacy of Ibudilast on lower limb circulation of diabetic patients with minimally impaired baseline flow: a study using color Doppler ultrasonography and laser Doppler flowmetry.

Ibudilast is a prostacyclin-mediated vasodilator and antiplatelet agent. The hemodynamic effects of ibudilast were evaluated in 41 patients with non-insulin-dependent diabetes mellitus by means of two-dimensional Doppler ultrasonography and laser Doppler blood flowmetry. Before and one hour after oral administration of ibudilast (10 mg), or elastase (1800 U) as a control, the cross-sectional area (CSA) of the dorsal pedis artery, its blood flow index (BFI), and dermal microcirculatory blood volume (MBV) were measured. In the ibudilast group, all of the parameters (CSA, BFI, and MBV) significantly increased as compared with the elastase group. These data suggest that ibudilast is effective in ameliorating diabetic macroangiopathy and microangiopathy of the lower limbs.

Scavenger effect of elastase on calcifications in liver, kidney and central nervous system tissues of rabbits with atherosclerosis induced by cholesterol-rich diet.

The inhibitory effect of elastase on calcification in liver, kidney and the central nervous system (CNS) was studied in rabbits with atherosclerosis induced by a cholesterol-rich diet. A total of 25 male rabbits were divided into six groups. In the first three groups, rabbits received a standard diet, a 1.5% cholesterol-rich diet or a 1.5% cholesterol-rich diet with intraperitoneal elastase (450 IU/kg.day) for 3 months. In the second three groups, rabbits received a standard diet, a 0.67% cholesterol-rich diet or a 0.67% cholesterol-rich diet with intraperitoneal elastase (450 IU/kg.day) for 6 months. Tissue calcium levels were then determined by neutron activation analysis. Tissue lipid levels were also measured. Dietary cholesterol increased serum lipid levels, atherosclerotic lesions and calcium levels in the CNS, but not in the liver or kidney. Calcium levels in the cerebellum and spinal cord of rabbits receiving the 0.67% cholesterol-rich diet plus elastase were significantly lower than those of rabbits receiving the 0.67% cholesterol diet alone. Elastase had a gradual inhibitory effect on the increase in calcium levels in CNS of cholesterol-induced atherosclerotic rabbits, reduced the increase in serum lipids and decreased the incidence of atherosclerotic lesions.

Effect of elastase on primary graft patency after femoralpopliteal arterial bypass for arteriosclerosis obliterans: a randomized, controlled study.

METHODS: Studies were carried out on 104 limbs with femoralpopliteal bypasses for arteriosclerosis obliterans (ASO). They were randomized to a group receiving elastase (10800 EL. U. P.O. per day) with an antiplatelet drug (Elastase group, 58 patients) or a group receiving only the antiplatelet drug (Control group, 46 patients). The follow-up period ranged from 24 to 36 months after operation at 22 institutions across Japan. RESULTS: The cumulative graft patency rate was higher in the Elastase group than the Control group, but the difference lacked statistical significance. When autogenous saphenous veins were used, the cumulative graft patency rate was significantly higher in the Elastase group than the Control group. CONCLUSIONS: The present study suggests that elastase is effective in maintaining graft patency in femoralpopliteal arterial bypass when an autogenous saphenous vein is used as a graft.

[Effects of elastase on experimentally induced aneurysms in rats].

The purpose is to study the potentiality of Elastase in preventing the development of experimentally induced aneurysms in rats. 64 Sprague-Dawly male rats of 5 months age were used. Unilateral common carotid artery ligation was done to effect hemodynamic changes in intracranial vessels. Posterior renal artery was ligated to induce hypertension which was further augmented by feeding with 1% saline and 0.1% BAPN, separately and in combination. The rats were divided into two equal groups of 32 and 32. The second group was in addition treated with intra-muscular injection of Elastase at a dose of 10 mg/kg/day for 6 days in a week. The rats were sacrificed at the end of 18 weeks to study the development of intracranial aneurysm and the effect of Elastase. There were 5 aneurysms in the first group comparing with 2 aneurysms in second group. The histopathology showed thickening of the intima and breakdown of elastic lamina at the site of the aneurysm. The effect of Elastase on these pathological changes is discussed.