Appendicular Skeletal Muscle Mass Correlates with Patient-Reported Outcomes and Physical Performance in Patients with Idiopathic Pulmonary Fibrosis.

Idiopathic pulmonary fibrosis (IPF), an incurable lung disease of unknown cause, often presents with losses of skeletal muscle mass. IPF requires comprehensive care, but it has not been investigated which skeletal muscle mass index reflects holistic management factors: pulmonary function, patient-reported outcomes (PROs), and physical performance. We compared three representative indices of skeletal muscle mass with holistic management factors in IPF patients. Twenty-seven mild to severe IPF patients (21 male) with the mean age of 76.1 ± 5.9 years were enrolled. The three indices were appendicular skeletal muscle mass index (ASMI), cross-sectional area of pectoralis major (PMCSA), and cross-sectional area of erector spinae muscles (ESMCSA). ASMI is considered as a gold standard for sarcopenia assessment, while PMCSA and ESMCSA are frequently used in IPF. As PROs, we assessed breathlessness with the modified Medical Research Council dyspnea scale (mMRC), symptoms with the chronic obstructive pulmonary disease assessment test (CAT), and health-related quality of life with St. George's Respiratory Questionnaire (SGRQ). For physical performance, peripheral muscle strength and 6-min walk distance (6MWD) were investigated. In this cross-sectional study, ASMI showed the greatest number of significantly correlated indices, such as pulmonary function, peripheral muscle strength, 6MWD, mMRC, and SGRQ. PMCSA showed the next greatest number of correlations, with peripheral muscle strength, 6MWD, and mMRC, whereas ESMCSA showed no significant correlations with any index. Thus, ASMI correlated with both PROs and physical performance, and PMCSA correlated mainly with physical performance. In conclusion, assessing ASMI is helpful for the comprehensive care of patients with IPF.

Bivalent HIV-1 fusion inhibitors based on peptidomimetics.

Membrane fusion is a valid target for inhibition of HIV-1 replication. A 34-mer fragment peptide (C34), which is contained in the HIV-1 envelope protein gp41, has significant anti-HIV activity. Previously, a dimeric derivative of C34 linked by a disulfide bridge at its C-terminus was found to have more potent anti-HIV activity than the C34 peptide monomer. To date, several peptidomimetic small inhibitors have been reported, but most have lower potency than peptide derivatives related to C34. In the present study we applied this dimerization concept to these peptidomimetic small inhibitors and designed several bivalent peptidomimetic HIV-1 fusion inhibitors. The importance of the length of linkers crosslinking two peptidomimetic compounds was demonstrated and several potent bivalent inhibitors containing tethered peptidomimetics were produced.

Dimeric C34 Derivatives Linked through Disulfide Bridges as New HIV-1 Fusion Inhibitors.

C34, a 34-mer fragment peptide, is contained in the HIV-1 envelope protein gp41. A dimeric derivative of C34 linked through a disulfide bridge at its C terminus was synthesized and found to display potent anti-HIV activity, comparable with that of a previously reported PEGylated dimer of C34REG. The reduction in the size of the linker moiety for dimerization was thus successful, and this result might shed some light on the mechanism of the suppression of six-helix bundle formation by these C34 dimeric derivatives. Addition of a Gly-Cys(CH2 CONH2 )-Gly-Gly motif at the N-terminal position of a C34 monomeric derivative significantly increased the anti-HIV-1 activity. This moiety functions as a new pharmacophore, and this might provide a useful insight into the design of potent HIV-1 fusion inhibitors.

Impact of Controlling Nutritional Status Score on Mortality in Elderly Patients with Idiopathic Pulmonary Fibrosis.

Background: There are only a few reports on the nutritional status and mortality of patients with idiopathic pulmonary fibrosis (IPF). As such, this study aims to investigate the relationship between controlling nutritional status (CONUT) and the mortality of elderly patients with IPF. Methods: A total of 170 IPF patients aged ≥65 years old who visited the rehabilitation department of our hospital between July 2014 and July 2021 (mean age: 75.7 ± 6.3 years, sex (male/female): 138/32, %FVC: 78.3 ± 18.3%) were retrospectively analyzed. The Kaplan-Meier method and log-rank test were applied. Furthermore, using a Cox proportional hazards model with multivariate analysis, we analyzed the relationship between all-cause mortality and baseline characteristics including CONUT. Results: Based on the CONUT score, the normal group included 101 cases, the mild group included 58 cases, the moderate group included 11 cases, and the severe group had 0 cases. There were 49 cases of all-cause mortality events, suggesting that the mortality of the moderate group was significantly poorer than that of the normal and mild groups (p < 0.05). Furthermore, multivariate analysis identified GAP stage (HR: 5.972, 95%CI: 2.901~12.291, p < 0.0001), mMRC scale (HR: 0.615, 95%CI: 0.389~0.971, p = 0.009), and CONUT (HR: 2.012, 95%CI: 1.192~3.395, p = 0.037) as factors significantly influencing mortality. Conclusions: Severe malnutrition was not observed in elderly patients with IPF. Moderate malnutrition was associated with a significantly higher risk of all-cause mortality, suggesting that CONUT is an important indicator for predicting mortality.

Determinants of Six-Minute Walk Distance in Idiopathic Pulmonary Fibrosis and Idiopathic Pleuroparenchymal Fibroelastosis.

Background: In idiopathic pulmonary fibrosis (IPF), 6-minute walking distance (6MWD) is an independent factor for mortality. Idiopathic pleuroparenchymal fibroelastosis (IPPFE) is a rare disease with physical features such as emaciation, but the relationship between IPPFE and 6MWD is unclear. In this study, we investigated the factors that cause a decrease in the percent of the predicted value of a 6-minute walk distance (%6MWD), including the disease entities, IPF and IPPFE. Methods: This study included 100 patients (IPF: 75 patients, IPPFE: 25 patients, age: 73.5 ± 7.2 years, sex: 73 males) who visited the rehabilitation department. Patients with a %6MWD ≥ 80% were assigned to the normal group (n = 54), and patients with a %6MWD < 80% were assigned to the decreased group (n = 46). The items showing a significant difference between groups were used as independent variables, after the consideration of multicollinearity, for a logistic analysis where %6MWD < 80% was used as the dependent variable. Results: The 6MWD results show that there was no significant difference between IPF and IPPFE in the absolute value of 6MWD and in the number of people with 6MWD ≥ 250 m, but when 6MWD was compared with %6MWD, the IPPFE group showed a significantly lower value than the IPF group (p = 0.013). Logistic regression analysis showed that only BMI (p = 0.032), GAP index (p = 0.043), and mMRC (p = 0.026) were factors that caused a decrease in %6MWD in 100 patients. Conclusion: The results suggest that leanness, shortness of breath and severity of illness are the most important factors that determine exercise tolerance, regardless of disease entity in IPF and IPPFE.

Benefits of Pulmonary Rehabilitation in Patients with Idiopathic Pulmonary Fibrosis Receiving Antifibrotic Drug Treatment.

Background: Although patients with idiopathic pulmonary fibrosis (IPF) often receive treatment with antifibrotic drugs (AFDs) and pulmonary rehabilitation (PR) concurrently, there are no reports on the effect of PR on patients with IPF receiving AFDs. Therefore, we investigated the effect of PR on patients with IPF receiving AFDs. Methods: Eighty-seven eligible patients with IPF (61 male; 72.0 ± 8.1 years; GAP severity stage I/II/III: 26/32/12) were recruited for the study. Patients who completed a 3-month outpatient PR program and those who did not participate were classified into four groups according to use of AFDs: PR group (n = 29), PR+AFD group (n = 11), treatment-free observational group (control group; n = 26), and AFD group (n = 21). There was no significant difference in age, sex, or severity among the groups. Patients were evaluated for physical functions such as 6-min walk distance (6MWD) and muscle strength, dyspnea, and health-related quality of life (HRQOL) at baseline and at 3 months. Results: In the PR group, dyspnea and 6MWD showed significant improvement after the 3-month PR program (p < 0.05 and p < 0.01, respectively). HRQOL was significantly worse at 3 months (p < 0.05) in the AFD group, but not in the other groups. The change in 6MWD from baseline to the 3-month time point was significantly higher in the PR+AFD group than in the AFD groups (p < 0.01). Conclusions: It was suggested that AFD treatment reduced exercise tolerance and HRQOL at 3 months; however, the concurrent use of PR may prevent or mitigate these effects.