Sternocleidomastoid Muscle Thickness Correlates with Exercise Tolerance in Patients with COPD.

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) have difficulties inhaling as the diaphragm becomes flattened and weakened due to lung hyperinflation. This weakened respiratory function is compensated for by the increased activity of the accessory respiratory muscles, such as the sternocleidomastoid muscle (SCM). OBJECTIVES: This study aimed to evaluate the difference in the SCM thickening fraction (SCM TF) of each respiratory phase (end-expiration, resting inspiration, and end-inspiration), as measured using ultrasonography (US), between patients with COPD and control subjects. We also evaluate the correlation between the SCM TF of each respiratory phase and exercise tolerance in patients with COPD. METHODS: Patients with COPD (n = 44) and age-matched controls (n = 20) underwent US for determination of the SCM TF. Ventilation parameters, including the peak oxygen uptake (peak VO2) and the change in the inspiratory capacity, were measured during cardiopulmonary exercise testing. The SCM thickness and TF was measured during end-expiration, resting breathing, and end-inspiration. RESULTS: The SCM was significantly thinner in patients with COPD than in controls at end-expiration. The increase in the SCM TF from end-expiration to end-inspiration in patients with COPD did not differ significantly from that in control subjects. In contrast, the SCM TF from end-expiration to resting inspiration was significantly greater in patients with COPD than in control subjects. The peak VO2 was strongly positively correlated with the SCM TF from end-expiration to end-inspiration in patients with COPD (r = 0.71, p < 0.01). CONCLUSIONS: The SCM may be thinner in patients with COPD than in controls. The SCM TF may also be associated with exercise tolerance.

Decreased Tongue Strength is Related to Skeletal Muscle Mass in COPD Patients.

Dysphagia is frequently observed in patients with chronic obstructive pulmonary disease (COPD). Decreased tongue strength is one of the causes of dysphagia, and it is often observed in patients with sarcopenia. Sarcopenia is also frequently observed in COPD patients. We hypothesized that tongue strength is lower in COPD patients compared to normal subjects. This was a single-center, observational, cross-sectional study. Maximum tongue pressure (MTP) was measured in 27 patients with COPD and 24 age-matched control subjects. We also evaluated handgrip strength, gait speed, and appendicular skeletal muscle mass to define subjects as having sarcopenia. We used bioelectrical impedance analysis to assess body composition. The eating assessment test-10 was used to diagnose dysphagia. MTP was significantly lower in COPD patients than in control subjects (33.8 ± 8.4 vs 38.0 ± 5.3; p = 0.032). All measures of muscle and fat free body mass, handgrip strength, and gait speed were also significantly lower in COPD patients compared to control subjects (p < 0.01). The prevalence of sarcopenia in COPD patients was higher than that in control subjects (6/27 versus 0/24; p = 0.007), but the prevalence of dysphagia was not different between groups (COPD: 5/27, versus control: 1/24; p = 0.112). MTP was moderately correlated with skeletal muscle mass index (r = 0.56, p = 0.003) and handgrip strength (r = 0.43, p = 0.027) in COPD patients. Tongue strength was lower in COPD patients compared to normal subjects, and decreased tongue strength may be correlated with sarcopenia in COPD patients.

Diaphragmatic excursion is correlated with the improvement in exercise tolerance after pulmonary rehabilitation in patients with chronic obstructive pulmonary disease.

BACKGROUND: In patients with chronic obstructive pulmonary disease (COPD), the maximum level of diaphragm excursion (DEmax) is correlated with dynamic lung hyperinflation and exercise tolerance. This study aimed to elucidate the utility of DEmax to predict the improvement in exercise tolerance after pulmonary rehabilitation (PR) in patients with COPD. METHODS: This was a prospective cohort study. Of the 62 patients with stable COPD who participated in the outpatient PR programme from April 2018 to February 2021, 50 completed the programme. Six-minute walk distance (6MWD) was performed to evaluate exercise tolerance, and ultrasonography was performed to measure DEmax. Responders to PR in exercise capacity were defined as patients who demonstrated an increase of > 30 m in 6MWD. The receiver operating characteristic (ROC) curve was used to determine the cut-off point of DEmax to predict responses to PR. RESULTS: Baseline levels of forced expiratory volume in 1 s, 6MWD, maximum inspiratory pressure, DEmax and quadriceps muscle strength were significantly higher, and peak dyspnoea of modified Borg (mBorg) scale score was lower in responders (n = 30) than in non-responders (n = 20) to PR (p < 0.01). In multivariate analysis, DEmax was significantly correlated with an increase of > 30 m in 6MWD. The area under the ROC curve of DEmax to predict responders was 0.915, with a sensitivity and specificity of 83% and 95%, respectively, at a cut-off value of 44.9 mm of DEmax. CONCLUSION: DEmax could adequately predict the improvement in exercise tolerance after PR in patients with COPD.

miR-155 inhibits mitophagy through suppression of BAG5, a partner protein of PINK1.

Removal of dysfunctional mitochondria is essential step to maintain normal cell physiology, and selective autophagy in mitochondria, called mitophagy, plays a critical role in quality control of mitochondria. While in several diseases and aging, disturbed mitophagy has been observed. In stem cells, accumulation of damaged mitochondria can lead to deterioration of stem cell properties. Here, we focused on miR-155-5p (miR-155), one of the most prominent miRNAs in inflammatory and aged tissues, and found that miR-155 disturbed mitophagy in mesenchymal stem cells (MSCs). As a molecular mechanism of miR-155-mediated mitophagy suppression, we found that BCL2 associated athanogene 5 (BAG5) is a direct target of miR-155. Reduction of BAG5 resulted in destabilization of PTEN-induced kinase (PINK1) and consequently disrupted mitophagy. Our study suggests a novel mechanism connecting aging and aging-associated inflammation with mitochondrial dysfunction in stem cells through a miRNA-mediated mechanism.

Transforming Growth Factor ß-Activated Kinase 1 Regulates Mesenchymal Stem Cell Proliferation Through Stabilization of Yap1/Taz Proteins.

Bone marrow-derived mesenchymal stem cells (BMMSCs) are multipotent stem cells capable of differentiation into a variety of cell types, proliferation, and production of clinically useful secretory factors. These advantages make BMMSCs highly useful for cell transplantation therapy. However, the molecular network underlying BMMSC proliferation remains poorly understood. Here, we showed that TGFß-activated kinase 1 (Tak1) is a critical molecule that regulates the activation of cell cycling and that Tak1 inhibition leads to quiescence in BMMSCs both in vivo and in vitro. Mechanistically, Tak1 was phosphorylated by growth factor stimulations, allowing it to bind and stabilize Yap1/Taz, which could then be localized to the nucleus. We also demonstrated that the quiescence induction by inhibiting Tak1 increased oxidized stress tolerance and improved BMMSC engraftment in intramuscular and intrabone marrow cell transplantation models. This study reveals a novel pathway controlling BMMSC proliferation and suggests a useful method to improve the therapeutic effect of BMMSC transplantation. Stem Cells 2019;37:1595-1605.

Ability to categorize end-feel joint movement according to years of clinical experience: an experiment with an end-feel simulator.

[Purpose] Discrimination between end-feel types is difficult, and years of clinical experience is considered a factor for improving the accuracy of the discrimination. The present study investigated whether the accuracy of classification of end-feel types improves with the increase in years of clinical experience. [Participants and Methods] In total, 44 therapists (range of years of clinical experience: 1-26 years) and 13 students were included. The participants identified the type of end feel simulated by our newly developed simulator. The proportion of correct answers of the therapists was compared with that of the students. For the therapists, years of clinical experience and their awareness of end feel were examined, and their relationships with the ability to classify end-feel types were analyzed. [Results] The therapists showed a higher ability to identify end-feel type than the students. The ability of the therapists improved according to their years of clinical experience. The cutoff values for years of clinical experience to improve the ability for identifying bone-to-bone, muscular, and tissue approximations were 15, 6, and 15, respectively. The therapists who were always conscious about end feel were associated with a higher ability to classify end-feel types. [Conclusion] Our present study demonstrated that the ability to classify end feel improves with the increase in years of clinical experience.

Involvement of ADAM12 in Chondrocyte Differentiation by Regulation of TGF-ß1-Induced IGF-1 and RUNX-2 Expressions.

A disintegrin and metalloproteinase 12 (ADAM12) is known to be involved in chondrocyte proliferation and maturation; however, the mechanisms are not fully understood. In this study, expression and localization of ADAM12 during chondrocyte differentiation were examined in the mouse growth plate by immunohistochemistry. Adam12 expression during ATDC5 chondrogenic differentiation was examined by real-time PCR and compared with the expression pattern of type X collagen. The clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 system was used to generate Adam12-knockout (KO) ATDC5 cells. Adam12-KO and Adam12 overexpressing cells were used for analyses of ADAM12 expression with or without TGF-ß1 stimulation. ADAM12 was identified predominantly in chondrocytes of the proliferative zone in mouse growth plates by immunohistochemistry. Adam12 was upregulated prior to Col10a1 during chondrogenic differentiation in wild-type ATDC5 cells. In Adam12-KO ATDC5 cells, following initiation of chondrogenic differentiation, we observed a reduction in Igf-1 expression along with an upregulation of hypertrophy-associated Runx2, Col10a1, and type X collagen protein expressions. In ATDC5 wild-type cells, stimulation with TGF-ß1 upregulated the expressions of Adam12 and Igf-1 and downregulated the expression of Runx2. In contrast, in Adam12-KO ATDC5 cells, these TGF-ß1-induced changes were suppressed. Adam12 overexpression resulted in an upregulation of Igf-1 and downregulation of Runx2 expression in ATDC5 cells. The findings suggest that ADAM12 has important role in the regulation of chondrocyte differentiation, potentially by regulation of TGF-ß1-dependent signaling and that targeting of ADAM12 may have a role in management of abnormal chondrocyte differentiation.

Laser-assisted cell removing (LACR) technology contributes to the purification process of the undifferentiated cell fraction during pluripotent stem cell culture.

Purification of undifferentiated cells by removing differentiated parts is an essential step in pluripotent stem cell culture. This process has been traditionally performed manually using a fine glass capillary or plastic tip under a microscope, or by culturing in a selective medium supplemented with anti-differentiation inhibitors. However, there are several inevitable problems associated with these methods, such as contamination or biological side-effects. Here, we developed a laser-assisted cell removing (LACR) technology that enables precise, fast, and contact-less cell removal. Using LACR combined with computational image recognition/identification-discriminating technology, we achieved automatic cell purification (A-LACR). Practicability of A-LACR was evaluated by two demonstrations: selective removal of trophoblast stem (TS) cells from human iPS and TS cell co-cultures, and purification of undifferentiated iPS cells by targeting differentiated cells that spontaneously developed. Our results suggested that LACR technology is a novel approach for stem cell processing in regenerative medicine.

Exertional dyspnoea and cortical oxygenation in patients with COPD.

This study was designed to investigate the association of perceived dyspnoea intensity with cortical oxygenation and cortical activation during exercise in patients with chronic obstructive pulmonary disease (COPD) and exertional hypoxaemia.Low-intensity exercise was performed at a constant work rate by patients with COPD and exertional hypoxaemia (n=11) or no hypoxaemia (n=16), and in control participants (n=11). Cortical oxyhaemoglobin (oxy-Hb) and deoxyhaemoglobin (deoxy-Hb) concentrations were measured by multichannel near-infrared spectroscopy. Increased deoxy-Hb is assumed to reflect impaired oxygenation, whereas decreased deoxy-Hb signifies cortical activation.Exercise decreased cortical deoxy-Hb in control and nonhypoxaemic patients. Deoxy-Hb was increased in hypoxaemic patients and oxygen supplementation improved cortical oxygenation. Decreased deoxy-Hb in the pre-motor cortex (PMA) was significantly correlated with exertional dyspnoea in control participants and patients with COPD without hypoxaemia. In contrast, increased cortical deoxy-Hb concentration was correlated with dyspnoea in patients with COPD and hypoxaemia. With the administration of oxygen supplementation, exertional dyspnoea was correlated with decreased deoxy-Hb in the PMA of COPD patients with hypoxaemia.During exercise, cortical oxygenation was impaired in patients with COPD and hypoxaemia compared with control and nonhypoxaemic patients; this difference was ameliorated with oxygen supplementation. Exertional dyspnoea was related to activation of the pre-motor cortex in COPD patients.

Serum butyrylcholinesterase and the risk of future type 2 diabetes: the Kansai Healthcare Study.

OBJECTIVE: Butyrylcholinesterase is synthesized in the liver. The serum butyrylcholinesterase level has been cross-sectionally reported to be higher in patients with diabetes, hyperlipidaemia, obesity and fatty liver than in those without them. It is not known whether serum butyrylcholinesterase is associated with the risk of future type 2 diabetes. DESIGN: A prospective cohort study. PARTICIPANTS: A total of 8470 Japanese men aged 40-55 years without type 2 diabetes at baseline. MEASUREMENTS: Type 2 diabetes was diagnosed if a fasting plasma glucose (FPG) level was ≥7·0 mmol/l, if a HbA1 c level was ≥6·5% or if participants were taking oral hypoglycaemic medication or insulin. RESULTS: During the 42,227 person-years of follow-up, 868 cases had developed type 2 diabetes. Serum butyrylcholinesterase was significantly positively correlated with body mass index (BMI), FPG, alanine aminotransferase (ALT), γ-glutamyltransferase (GGT) and triglycerides (TG), whereas negatively with high-density lipoprotein (HDL) cholesterol. In Cox proportional hazards models, after adjusting for age, BMI, FPG, alcohol consumption, smoking habit, walk to work, regular leisure-time physical activity and family history of diabetes, the highest quartile (398-806 IU/l) of serum butyrylcholinesterase increased the risk of type 2 diabetes compared with the lowest quartile (56-311 IU/l) [hazard ratio (HR) 1·41 (95% confidence interval (CI), 1·14-1·74)]. After further adjusting for ALT and GGT, this association remained [HR 1·40 (95% CI, 1·13-1·73)]. Furthermore, this association was significant independent of TG and HDL cholesterol. CONCLUSIONS: Elevated serum butyrylcholinesterase was independently associated with an increased risk of future type 2 diabetes.

Drinking pattern and risk of chronic kidney disease: the kansai healthcare study.

BACKGROUND/AIMS: The association between alcohol consumption and the risk of chronic kidney disease (CKD) has been reported. What is not known is whether drinking pattern combined with the weekly frequency of alcohol consumption and the quantity per drinking day is associated with the risk of CKD. METHODS: We enrolled 9,112 Japanese nondiabetic men aged 40 to 55 years with absence of proteinuria, an estimated glomerular filtration rate (eGFR) of 60 ml/min/1.73 m(2) or higher, and not on antihypertensive medications at baseline. CKD was defined if eGFR was <60 ml/min/1.73 m(2). The weekly frequency classification was nondrinkers, 1-3 drinking days/week, or 4-7 drinking days/week. The quantity consumed per drinking day was classified as 0.1-23.0 g ethanol/drinking day, 23.1-46.0 g ethanol/drinking day, 46.1-69.0 g ethanol/drinking day, and ≥69.1 g ethanol/drinking day. RESULTS: During the 79,099 person-years, 1,253 subjects developed CKD. Compared to nondrinkers, those who consumed 23.1-46.0 or 46.1-69.0 g ethanol/drinking day on 4-7 drinking days/week had a decreased risk of CKD (multiple-adjusted hazard ratio (HR) 0.62 (0.52-0.74) and 0.76 (0.59-0.97), respectively). The association between the quantity per drinking day and the incidence of CKD was U-shaped among each category of the weekly frequency. HRs within similar categories of quantity per drinking day were lower in the 4-7 drinking days/week group than in the 1-3 drinking days/week group. CONCLUSION: Among middle-aged Japanese men, the people who drank middle-range quantity, specifically who drank 4-7 days/week, had lower risk of CKD than nondrinkers.

Cysteamine supplementation during in vitro maturation (IVM) of rabbit oocyte improves the developmental capacity after intracytoplasmic sperm injection.

PURPOSE: Current approaches to in vitro maturation (IVM) may result in low efficiency and inadequate quality of the oocytes due to insufficient cytoplasmic maturation. Although positive effects of the cysteamine supplementation in IVM medium for oocyte nuclear maturation or male pronuclear formation have been confirmed, it is still controversial whether the cysteamine addition affects embryo development after IVM. We aimed here to confirm the effect of cysteamine addition into IVM medium for subsequent embryo development in vitro. METHODS: We administered the cysteamine to the IVM culture of rabbit immature oocytes at various concentrations and observed the developmental rate, speed to reach blastocyst stage and cell numbers at the blastocyst stage. RESULTS: Cysteamine supplementation improved developmental rate to blastocyst stage of the IVM oocytes. On the other hand, addition of glutathione (GSH) inhibitor buthionine sulfoximine inhibited GSH accumulation in the oocytes and subsequent embryo development to the blastocyst stage. CONCLUSIONS: Controlling the GSH quantity of IVM oocytes may be an important factor for success of embryo development, and it is quite probable that a cysteamine supplementation can contribute to an increase of GSH content in oocyte.

Mechanical stimulation of cyclic tensile strain induces reduction of pluripotent related gene expressions via activation of Rho/ROCK and subsequent decreasing of AKT phosphorylation in human induced pluripotent stem cells.

Mechanical stimulation has been shown to regulate the proliferation and differentiation of stem cells. However, the effects of the mechanical stress on the stemness or related molecular mechanisms have not been well determined. Pluripotent stem cells such as embryonic stem (ES) cells and induced pluripotent stem (iPS) cells are used as good materials for cell transplantation therapy and research of mammalian development, since they can self-renew infinitely and differentiate into various cell lineages. Here we demonstrated that the mechanical stimulation to human iPS cells altered alignment of actin fibers and expressions of the pluripotent related genes Nanog, POU5f1 and Sox2. In the mechanically stimulated iPS cells, small GTPase Rho was activated and interestingly, AKT phosphorylation was decreased. Inhibition of Rho-associated kinase ROCK recovered the AKT phosphorylation and the gene expressions. These results clearly suggested that the Rho/ROCK is a potent primary effector of mechanical stress in the pluripotent stem cells and it participates to pluripotency-related signaling cascades as an upper stream regulator.

Cyclic compression-induced p38 activation and subsequent MMP13 expression requires Rho/ROCK activity in bovine cartilage explants.

OBJECTIVE: Excessive mechanical stress on the cartilage causes the degradation of the matrix, leading to the osteoarthritis (OA). Matrix metalloproteinases 13 (MMP13) is a major catalytic enzyme in OA and p38 plays an important role in its induction. However, precise pathway inducing p38 activation has not been elucidated. We hypothesized here that the small GTPase Rho and its effector ROCK might function in upper part of the mechanical stress-induced matrix degeneration pathway. METHODS: Bovine metacarpal phalangeal articular cartilage explants were loaded with 1 MPa dynamic compression for 6 h with or without a ROCK specific inhibitor Y27632 or/and a p38 specific inhibitor SB202190. Then p38 phosphorylation and MMP13 expression were assessed by western blot or/and quantitative RT-PCR. Rho-activity was measured by pull-down assay using glutathione S-transferase fusion protein of Rho binding domain. RESULTS: Cyclic compression caused Rho activation, p38 phosphorylation and MMP13 expression. Both Y27632 and SB202190 were found to block the mechanical stress-enhanced p38 phosphorylation and subsequent MMP13 expression. CONCLUSIONS: The present results show that p38 phosphorylation and MMP13 expression are regulated by Rho/ROCK activation, and support the potential novel pathway that Rho/ROCK is in the upper part of the mechanical stress-induced matrix degeneration cascade in cartilage comprised of p38 and MMP13.

Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ): a patient-based evaluation tool for hip-joint disease. The Subcommittee on Hip Disease Evaluation of the Clinical Outcome Committee of the Japanese Orthopaedic Association.

BACKGROUND: The Japanese Orthopaedic Association Hip Score is widely used in Japan, but this tool is designed to reflect the viewpoint of health-care providers rather than that of patients. In gauging the effect of medical therapies in addition to clinical results, it is necessary to assess quality of life (QOL) from the viewpoint of patients. However, there is no tool evaluating QOL for Japanese patients with hip-joint disease. METHODS: With the aim of more accurately classifying QOL for Japanese patients with hip-joint disease, we prepared a questionnaire with 58 items for the survey derived from 464 opinions obtained from approximately 100 Japanese patients with hip-joint disease and previously devised evaluation criteria. In the survey, we collected information on 501 cases, and 402 were subjected to factor analysis. From this, we formulated three categories-movement, mental, and pain-each comprising 7 items, for a total of 21 items to be used as evaluation criteria for hip-joint function. RESULTS: The Cronbach's α coefficients for the three categories were 0.93, 0.93, and 0.95, respectively, indicating the high reliability of the evaluation criteria. The 21 items included some related to the Asian lifestyle, such as use of a Japanese-style toilet and rising from the floor, which are not included in other evaluation tools. CONCLUSIONS: This self-administered questionnaire may become a useful tool in the evaluation of not only Japanese patients, but also of members of other ethnic groups who engage in deep flexion of the hip joint during daily activities.

Effectiveness of Rehabilitation for Cancer Patients with Bone Metastasis.

Objectives: Advances in cancer treatment have led to extended survival, and, as a result, the number of patients with bone metastases is increasing. Activities of daily living (ADL) decrease with bone metastasis and the need for rehabilitation is increasing. This study examined the effects of rehabilitation in patients with bone metastases. Methods: We retrospectively reviewed data of cancer patients with bone metastasis who received rehabilitation between 2016 and 2018. Efficacy of rehabilitation was evaluated in 92 patients as the change in the Functional Independence Measure (FIM) score divided by rehabilitation days (FIM change/day) and assessed by different metastatic sites. Results: Overall FIM scores significantly improved after rehabilitation. Moreover, FIM change/day improved in patients with pelvic metastases (n=44) more than in patients with other metastatic sites (n=48) (P=0.015). In FIM motor components, improvements in toilet, tub/shower, walk/wheelchair, and stairs were significantly greater in patients with pelvic metastasis than in those with other metastasis sites. Conclusions: Rehabilitation improved ADL status to a greater extent in patients with pelvic metastases than in those with other metastasis sites. Patients with pelvic metastases may fear fractures, limiting their ADL, but rehabilitation could eliminate this fear and improve FIM.

Elevated white blood cell count worsens proteinuria but not estimated glomerular filtration rate: the Kansai Healthcare Study.

BACKGROUND/AIMS: No prospective studies have estimated the association between white blood cell (WBC) count and the risk of proteinuria. We prospectively examined the relationships of WBC count, as a marker of inflammation, with two outcomes: proteinuria and low estimated glomerular filtration rate (eGFR). METHODS: We enrolled 10,008 Japanese men aged 40-55 years who had neither proteinuria nor low eGFR and were not taking antihypertensive medications at entry. Proteinuria was defined as 1+ or higher on urine dipstick. Low eGFR was defined if eGFR was <60 ml/min/1.73 m(2). RESULTS: During the 49,644 person-years of follow-up, 1,557 cases of proteinuria were confirmed. After adjusting for age, body mass index, fasting plasma glucose, systolic blood pressure, diastolic blood pressure, antidiabetic medications, alcohol consumption, smoking, regular leisure-time physical activity and eGFR, the highest quintile (≥7.51 × 10(3)/µl) of WBC count was independently associated with an increased risk of incidence of proteinuria [HR: 1.45 (95% CI: 1.23-1.73)] compared with the lowest quintile (≤4.80 × 10(3)/µl). On the other hand, during 52,833 person-years, we confirmed 439 cases of low eGFR. In multivariate models, there was no association between WBC count and low eGFR. CONCLUSION: Elevated WBC count was independently associated with an increased risk of proteinuria, but not low eGFR.

Activation of the prefrontal cortex is associated with exertional dyspnea in chronic obstructive pulmonary disease.

BACKGROUND: Exertional dyspnea is the primary symptom that limits exercise in patients with chronic obstructive pulmonary disease (COPD). It is unknown which activated brain area is associated with this symptom in COPD patients. OBJECTIVES: To investigate the activation of cortical areas associated with dyspnea during exercise in COPD patients. METHODS: COPD patients (n = 10) and age-matched controls (n = 10) performed mild-intensity constant work rate cycle exercise (40% of their symptom-limited peak work rates) for 10 min, while cerebral hemodynamics and oxygenation were measured by near-infrared spectroscopy (NIRS). Ventilatory responses (breathing pattern and pulmonary gas exchange) and Borg scale ratings of dyspnea and leg fatigue were measured during exercise. Three NIRS probes were placed over the prefrontal and temporoparietal cortical regions of the subjects' heads. Changes in cortical oxyhemoglobin (oxy-Hb), deoxyhemoglobin (deoxy-Hb), and total hemoglobin (total Hb) concentrations from baseline recordings were measured. Increased oxy-Hb (oxygenation) was assumed to reflect cortical activation. RESULTS: Oxy-Hb concentration was significantly increased in the prefrontal region during exercise in both groups but not in the temporoparietal regions. The change in prefrontal oxy-Hb concentration of COPD patients was not different from that of controls. Dyspnea scores were positively correlated with changes in oxy-Hb concentrations of the prefrontal regions in both groups. Multivariate analysis showed that oxy-Hb concentration in the prefrontal region was the best predictor of dyspnea in both groups. CONCLUSIONS: Exertional dyspnea was related to activation (oxygenation) of the prefrontal cortex in COPD patients and control subjects.

Effect of Pulmonary Rehabilitation on Erector Spinae Muscles in Individuals With COPD.

BACKGROUND: A recent paper reported that low muscle mass in the erector spinae muscles (ESM) was strongly associated with poor prognosis and declining muscle mass over time in subjects with COPD. However, effects of pulmonary rehabilitation (PR), if any, on ESM mass have not been reported. We hypothesized that PR reduces the annual decline in ESM mass. METHODS: This was a retrospective cohort study. Thirty-nine subjects with COPD who received PR and underwent chest computed tomography before and after PR were evaluated (rehabilitation group). We also evaluated 39 age-matched subjects with COPD who did not receive PR (nonrehabilitation group). Data were collected from August 2010 until March 2020 in both groups. The ESM cross-sectional area (ESMCSA) was measured using axial computed tomography images, and annual changes were calculated. The 6-min walk distance (6MWD) was measured before and after PR; the minimum clinically important difference was defined as 30 m. RESULTS: ESMCSA declined in the nonrehabilitation group over time (-116.0 ± 141.2 mm2/y) but increased in the PR group (51.0 ± 95.3 mm2/y; P < .001). The annual increase in ESMCSA was significantly higher among subjects with an increase in 6MWD that exceeded the minimum clinically important difference compared with nonresponders in the rehabilitation group. The annual change in ESMCSA was negatively correlated with comorbidity index, and triple therapy (long-acting ß2-agonist/long-acting muscarinic antagonist/inhaled corticosteroid) had a favorable effect on annual change in ESMCSA. Multiple regression analysis revealed that only PR was an independent factor for annual change in ESMCSA. CONCLUSIONS: ESM mass was shown to decline yearly in subjects with COPD. The annual decline in muscle mass was reduced by PR.