Objective
To characterise changes in respiratory muscle strength, physical function, and dyspnoea in patients who underwent pre‐ and post‐operative exercise intervention following lobectomy for ...non‐small‐cell lung cancer (NSCLC).
Methods
This retrospective study included NSCLC patients who underwent lobectomy via video‐assisted thoracoscopic surgery (VATS) or posterolateral thoracotomy (PLT) and pre‐ and post‐operative exercise intervention consisting of breathing, flexibility, resistance, aerobic exercises, coughing/huffing techniques, and early mobilisation. Maximum mouth inspiratory (Pimax) and expiratory pressures (Pemax), 6‐min walk distance (6MWD), quadriceps force (QF), and modified Medical Research Council (mMRC) dyspnoea scale were evaluated preoperatively, at hospital discharge, and post‐lobectomy 1 and 3 months.
Results
Data from 41 patients were analysed. At hospital discharge, the Pimax, Pemax, 6MWD, and mMRC dyspnoea scores were lower than pre‐operatively; QF remained unchanged; Pimax and 6MWD recovered to pre‐operative values at post‐lobectomy 1 month; and Pemax and mMRC dyspnoea scores recovered at 3 months. During sub‐analysis, Pimax and mMRC dyspnoea scores in the VATS (n = 24) and PLT groups (n = 17) recovered to pre‐operative values at post‐lobectomy 1 and 3 months.
Conclusion
After lobectomy, respiratory muscle strength, physical function, and dyspnoea in patients who underwent exercise intervention returned to pre‐operative values at post‐lobectomy 3 months.
Abstract
BACKGROUND AND AIMS
Proteinuria is a major risk factor for the progression of chronic kidney disease. Protein overload in the proximal tubular epithelial cells causes oxidative stress, ...lysosomal dysfunction, inflammation and apoptosis, resulting in proximal tubule dysfunction. Recent studies have focussed on the association between proximal tubule injury and cellular senescence and the development of drugs targeting and removing senescent proximal tubular cells. Senescent cells show resistance to apoptosis and persistently secrete inflammatory cytokines, resulting in chronic inflammation. It has been suggested that excess proliferation induced by fatty acids causes senescence of proximal tubular cells. However, the association between protein overload, proliferation and cellular senescence in proximal tubular cells remains unclear. The present study aimed to clarify the effect of protein overload on cell proliferation and senescence in a proteinuric mouse model and in an immortalized proximal tubular epithelial cell line. Moreover, it was evaluated whether the endocytic receptors for protein uptake, megalin and cubilin, affect protein overload-induced proliferation and senescence using knockout (KO) of megalin and cubilin in the proteinuric mouse model.
METHOD
Experiments were performed using podocin-KO (proteinuric mouse model) and megalin-cubilin-podocin triple-KO mice. Kidneys from these mice were analysed using immunohistochemical and immunofluorescent staining. Immortalized proximal tubular cells (RPTEC/TERT1, ATCC) were used for in vitro experiments, wherein RPTEC/TERT1 cells were incubated with 0.1–10 mg/mL of human serum albumin (HSA; Sigma), fatty acid-free HSA (Sigma), and transferrin (Sigma). Western blotting, quantitative rt-PCR, senescence-associated beta-galactosidase (SA-β-gal) staining and immunofluorescence were performed to analyse cellular senescence. The effect of a PKC activator (phorbol 12-myristate 13-acetate) and an inhibitor (Go6983) on proliferation and senescence was also evaluated.
RESULTS
The proliferation markers EdU incorporation, PCNA (Figure 1) and Ki-67 were detected in proximal tubular cells of podocin-KO mice, but not in wild-type mice. In triple-KO mice, a decrease in PCNA-positive tubules was observed. This suggests that protein reabsorption via megalin and cubilin provoked cell proliferation. Light microscopy analysis and a proliferation assay with BrdU incorporation revealed that HSA overload-induced the proliferation of RPTEC/TERT1 cells, whereas fatty acid-free HSA or transferrin had no effect on the proliferation of RPTEC/TERT1 cells. Western blot analysis showed that HSA treatment, but not fatty acid-free HSA treatment, induced alterations in proliferation (PCNA and Ki-67), cell cycle (cyclin A, D, and Rb), cellular senescence (p21 and p16), and DNA injury (γ-H2AX). Using immunofluorescence, an increase in p21 and p16 expression was also observed in HSA-treated cells. Moreover, the HSA-treated cells showed positive staining for SA-β-gal. These results suggest that fatty acids bound to HSA induce cell proliferation and senescence. Furthermore, results showed that a PKC inhibitor suppressed HSA-induced proliferation and senescence, while a PKC activator accelerated these alterations without HSA treatment.
CONCLUSION
The present study showed that fatty acid-associated albumin induced proliferation and senescence of the proximal tubule cells, which were dependent on megalin/cubilin endocytosis of filtered protein. PKC activation is at least in part related to cell proliferation and senescence. It is unknown which molecular switch determine the cell cycle fate.
Abstract
Background and Aims
Megalin, an endocytic receptor in proximal tubular cells, plays a critical role in renal tubular protein reabsorption. We previously reported that oxidative stress ...induced the temporally increase in renal megalin expression through the PI3K/AKT signaling pathway, but that megalin elevation is normalized or decreased during long term exposure to oxidative stress (hydrogen peroxide). However, the underlying mechanisms are unclear. Studies have addressed that megalin is subjected to regulated intramembrane proteolysis (RIP). Intracellular megalin COOH-terminal fragment (MCTF) is produced by protein kinase C-regulated, metalloprotease-mediated ectodomain shedding and further cleavage by gamma-secretase to produce the soluble megalin intracellular domain (MICD). The MICD in turn translocates to the nucleus where it decreases expression of the Lrp2 gene encoding megalin. In the present study, we evaluated the effect of megalin RIP on the oxidative stress-regulated megalin expression.
Method
HK-2 cells were cultured with hydrogen peroxide (0.4 mmol/l) for 4.5 or 24 h, followed by treatment with gamma-secretase inhibitor, Compound E (5 mmol/L) or PKC activator, Phorbol 12-myristate 13-acetate (PMA, 0.5 mmol/L). Megalin expression was determined by performing western blotting or real-time PCR. The MCTF in medium was detected by western blotting. In animal experiments, Sprague-Dawley rats were randomly divided into two groups (n = 5): (i) STZ group (diabetic phenotype induced by streptozotocin administration) and (ii) sham group (vehicle). Urine was collected at two weeks after STZ administration, and the excretion of MCTF in urine was analyzed.
Results
Treatment of HK-2 cells with hydrogen peroxide (0.4 mmol/L) significantly increased megalin protein and mRNA levels at 4.5 h. Pretreatment of Compound E showed further increase in megalin expression in hydrogen peroxide-exposed cells. It was also found that presenilin-1 and -2, which are components of gamma-secretase, double knockdown with siRNA increased megalin expression in hydrogen peroxide treated-cells. On the other hand, PMA treatment inhibited the increase in both megalin protein and mRNA levels. In the cells treated with hydrogen peroxide for 24 h, megalin mRNA levels were normalized, but pretreatment of Compound E kept the elevation in megalin mRNA levels at 24 h after the treatment with hydrogen peroxide. Interestingly, megalin MCTF in the medium was increased by hydrogen peroxide treatment in a dose-dependent manner. Furthermore, megalin MCTF excretion in the urine of STZ-induced diabetes was significantly increased compared to sham rats.
Conclusion
These results suggested that oxidative stress-induced megalin upregulation was inhibited by RIP activation of megalin, suggesting that megalin RIP plays a role as a negative feedback system to oxidative stress-induced megalin upregulation. Furthermore, our data indicate that oxidative stress induces urinary excretions of MCTF in diabetic rats during the normoalbuminuric stage and potentially act as a marker of diabetic kidney disease.
Patients with plaster cast immobilization of the lower limb have an estimated symptomatic venous thromboembolism rate of 5.5%. However, there is currently no practical physical prophylaxis for ...deep-vein thrombosis (DVT). The objective of this study was to examine the effects of forced deep breathing on peak blood velocity in the superficial femoral vein (PBVFV), which is a surrogate measure of the efficacy of thromboprophylaxis against DVT, in patients with plaster cast immobilization of the lower limb.
Nine young males and 18 elderly males were recruited. We immobilized the right lower limb of each subject with a plaster splint and measured PBVFV during forced deep breathing in supine and sitting positions.
In all subjects, PBVFV during forced deep breathing in both positions was significantly higher than at rest. There was no significant difference in the PBVFV change ratio for three breathing rates in the sitting position for the young subjects (15breaths/min: 415%, 5breaths/min: 475%, 3breaths/min: 483%), whereas that for the elderly subjects at 3breaths/min (449%) was significantly higher than that at 15breaths/min (284%).
Forced deep breathing significantly increased PBVFV in patients with plaster cast immobilization of the lower limb in both supine and sitting positions. Testing the efficacy and adherence in clinical contexts, and following up with the incidence rate of DVT in future studies, is necessary for the development of a new physical prophylaxis for DVT.
•Forced deep breath increases venous blood velocity in healthy males with plaster cast.•Peak blood velocity in the femoral vein is influenced by posture or pace of breaths.•Change ratio of blood velocity resulted in at most a 4.8-fold increase at sitting.
Abstract . The clinical utility of intermittently scanned continuous glucose monitoring (isCGM) in patients with coronavirus disease 2019 (COVID-19) is unclear. Hence, we investigated the accuracy of ...isCGM in COVID-19 patients during dexamethasone therapy. We evaluated the accuracy of the FreeStyle Libre via smartphone isCGM device compared to point-of-care (POC) fingerstick glucose level monitoring in 16 patients with COVID-19 (10 with and 6 without diabetes, 13 men ; HbA1c 6.9+-1.0%) . Overall, isCGM correlated well with POC measurements (46.2% and 53.8% within areas A and B of the Parkes error grid, respectively) . The overall mean absolute relative difference (MARD) for isCGM compared to POC measurements was 19.4%. The MARDs were 19.8% and 19.7% for POC blood glucose measurements ranging from 70 to 180 mg/dL and >180 mg/dL, respectively. When divided according to the presence and absence of diabetes, both groups of paired glucose measurements showed a good correlation (56.3% and 43.7%, and 27.1% and 72.9% within the A and B areas in patients with and without diabetes, respectively) , but the MARD was not significant but higher in patients without diabetes (16.5% and 24.2% in patients with and without diabetes) . In conclusion, although isCGM may not be as accurate as traditional blood glucose monitoring, it has good reliability in COVID-19 patients with and without diabetes during dexamethasone therapy.
Immunotherapy can become a crucial therapeutic option to improve the prognosis of patients with non-small-cell lung cancer (NSCLC). Here, we evaluated the impact of programmed cell death ligand-1 ...(PD-L1) expression in surgically resected NSCLCs.
We estimated PD-L1 expression in 229 consecutive NSCLC specimens using rabbit polyclonal antibodies to human PD-L1 in a SP263 immunohistochemical assay and evaluated PD-L1 expression for potential associations with clinicopathological parameters and survival time.
PD-L1 expression was significantly higher in tumors from men or current smokers. Squamous cell carcinoma histology was independently associated with high PD-L1 expression according to multivariate analysis (p = 0.015). The 5-year survival rate of patients was 70%, and the difference in the 5-year survival rate according to PD-L1 expression was not statistically significant (high expression group 67% vs. low expression group 68%); however, the squamous cell carcinoma group exhibited significantly lower 5-year survival rates as compared to the non-squamous cell carcinoma group (53 and 71%, respectively; p = 0.026).
Here, we revealed high PD-L1 expression and poor prognosis observed in patients with surgically resected squamous NSCLC as compared with non-squamous NSCLC. Our results support the identification of patient subsets that most likely respond to anti-PD-1 therapy as the first step in precision medicine.
Necrotizing pneumonia caused by Panton-Valentine leukocidin (PVL)-positive community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has high mortality, and is currently a serious ...clinical issue. PVL is a two-component toxin consisting of LukS-PV and LukF-PV. PVL was shown to cause necrosis in target cells by forming pores consisting of an octamer comprised of LukS-PV and LukF-PV. However, because of the specificity of PVL toward several target cells and species, the detailed action of PVL remains controversial. Therefore, we focused on necrotizing pneumonia caused by PVL-positive Staphylococcus aureus and clarified the effects of PVL on alveolar macrophages, which play a central role in innate immunity in the alveolar space. We constructed recombinant PVL (rPVL) components and stimulated alveolar macrophages isolated from rabbits, and then evaluated the cytotoxicity and pro-inflammatory cytokine release. Recombinant LukS-PV (rLukS-PV), but not recombinant LukF-PV (rLukF-PV), induced pro-inflammatory cytokine release. Especially, TNF-α release was mediated via the C5a receptor (C5aR) expressed in rabbit alveolar macrophages and rPVL, consisting of rLukS-PV and rLukF-PV, was highly toxic to rabbit alveolar macrophages via the same receptor. Our results, which reveal the action of PVL via C5aR on alveolar macrophages, may be useful for understanding the mechanism of necrotizing pneumonia caused by PVL.
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