Degradable Cell-Adhesive Hybrid Hydrogels by Cross-Linking of Gelatin with Poly(2-isopropenyl-2-oxazoline).

This study focused on the cross-linking of poly(2-isopropenyl-2-oxazoline) (PiPOx) with gelatin to obtain strong, degradable hybrid hydrogels with good cell adhesion. The molecular weight and concentration of PiPOx and the PiPOx-to-gelatin ratio were varied to adjust the mechanical and swelling properties of the hybrid hydrogels. The swelling degree of PiPOx-gelatin hydrogels in water ranged between 1260 and 810%, with the corresponding Young's compressive moduli ranging from 77 to 215 kPa. Rheological measurements demonstrated the mechanical stability of the hydrogels. The hydrogels exhibited substantial degradation in Dulbecco's phosphate-buffered saline (DPBS) and cell culture medium within several weeks, indicating their degradability and responsiveness. The cell adhesion assay with primary human foreskin fibroblasts revealed the hybrid hydrogels are noncytotoxic and support cell attachment and proliferation. These strong hydrogels thus show excellent potential as biomedical cell scaffolds, combining the tunability and strength of PiPOx hydrogels with gelatin's cell-interactive properties while the ester-containing cross-links provide tunable degradability.

Changes in the physical and affective dimensions of dyspnoea after a home-based pulmonary rehabilitation in fibrotic idiopathic interstitial pneumonias.

Background: Our objective was to evaluate the short-, medium- and long-term benefits of home-based pulmonary rehabilitation (PR) on the physical and affective components of dyspnoea in people with fibrotic idiopathic interstitial pneumonias (f-IIPs). Anxiety and depressive symptoms, fatigue, health-related quality of life and exercise tolerance were also assessed. Methods: Data on 166 individuals with f-IIPs who enrolled in an 8-week home-based PR programme (weekly supervised 90-min session) were retrospectively analysed. Assessments included the Dyspnoea-12 (D-12) questionnaire, Hospital Anxiety and Depression Scale, Fatigue Assessment Scale, Visual Simplified Respiratory Questionnaire and 6-min stepper test, and were performed at home at short, medium (6 months) and long (12 months) term. Results: Among the 166 individuals with f-IIPs who enrolled in PR, 75 (45%) and 91 (55%) participants had a diagnosis of idiopathic pulmonary fibrosis and fibrosing non-specific interstitial pneumonia, respectively, and 87 (52%) participants concluded a full year of follow-up. In the total group, both physical and affective components of dyspnoea were improved, at short, medium and long term, after PR. Overall, half of the participants reached the minimally important difference of 3 points of the D-12 questionnaire at the end of PR, and at the 6- and 12-month follow-ups. Anxiety and depressive symptoms, fatigue and health-related quality of life were also improved, while the short-term benefits in exercise tolerance were not maintained 1 year after PR. Conclusion: An individualised home-based PR programme resulted in short-, medium- and long-term improvements in both physical and affective components of dyspnoea assessed by the D-12 questionnaire.

Frequency and characteristics of refractory dyspnea in idiopathic fibrosing interstitial pneumonia.

Patients with idiopathic fibrosing interstitial pneumonias (f-IIPs) mainly suffer from dyspnea. Refractory dyspnea, defined as persistent dyspnea despite optimal treatment, could be the signal to prescribe dyspnea relievers. We aimed to examine the prevalence and characteristics of refractory dyspnea in consecutive patients with f-IIPs. Refractory dyspnea was defined by an mMRC≥3 and also by a VAS dyspnea score≥2 at rest. The sensory and affective characteristics of refractory dyspnea (mMRC≥3) and associated quality of life (QoL) anxiety and depression were compared with non-refractory dyspnea (mMRC1-2) using the Multidimensional Dyspnea Profile (MDP), King's Brief Interstitial Lung Disease (KBILD) and Hospital Anxiety and Depression scale (HADs). We included 40 patients (24 men), aged 72 [68-79], FVC of 71 % [59-86] and DLCO 47 % [40-49]. Refractory dyspnea, was found in 38 % (95%CI:23-54) when defined by mMRC≥3 and in 67 % (95%CI:50-81) using a resting VAS dyspnea score ≥2. The agreement between the two definitions was low. Patients with refractory dyspnea (mMRC≥3) were more often women (60 % vs.28 %, p = 0.046), had a lower DLCO (24 % [22-43] vs.47 % [43-51], p = 0.014) and more frequently used oxygen (60 % vs.12 %, p = 0.003); they experience more intense air hunger (5/10 [3-6] vs.2/10 [0-5], p = 0.018)). No significant differences were observed in VAS, MDP, KBILD, or HADs scores between refractory and non-refractory dyspnea patients. Our results indicate a significant frequency of refractory dyspnea in patients with f-IIPs and an association with air hunger but no impact on the affective dimension of dyspnea, anxiety, depression and QoL, suggesting that the mMRC score might not accurately identify patients distressed by their breathlessness.