Krebs von den Lungen-6 levels at admission predicts exercise-induced hypoxemia before and after discharge in patients with COVID-19

BACKGROUND

There are no reports of exercise-induced hypoxemia in patients with coronavirus disease 2019 (COVID-19). Additionally, the predictive factors and prevalence of exercise-induced hypoxemia are unknown. This study investigated the incidence and predictive factors of exercise-induced hypoxemia before and after discharge in patients with COVID-19.

METHODS

We enrolled 77 patients diagnosed with COVID-19 who were hospitalized between November 2020 and October 2021 and who underwent a 6-min walk test before and after discharge. Based on the test results, we classified patients into exercise-induced and non-exercise-induced hypoxemia groups and investigated the predictive factors of exercise-induced hypoxemia using logistic regression analysis.

RESULTS

The incidences of exercise-induced hypoxemia in patients with COVID-19 were 37.7% and 19.5% before and after discharge, respectively. At admission, the Krebs von den Lungen-6 levels was the associated factor for exercise-induced hypoxemia in patients with COVID-19 before and after discharge, with cut-off values of 314 U/mL and 367 U/mL, respectively. Age and lactate dehydrogenase levels were the associated factors for exercise-induced hypoxemia in patients with COVID-19 before discharge, with cut-off values of 61 years and 492 U/L, respectively.

CONCLUSIONS

Some patients with COVID-19 may continue to experience exercise-induced hypoxemia after discharge. Age, lactate dehydrogenase, and Krebs von den Lungen-6 levels at admission could serve as predictive markers of exercise-induced hypoxemia before and after discharge in these patients.

Cryptogenic organizing pneumonia after withdrawal of systemic corticosteroids for chronic eosinophilic pneumonia and severe asthma under benralizumab treatment

A 79-year-old woman with severe asthma developed chronic eosinophilic pneumonia (CEP). After CEP resolved with oral prednisolone at 30 mg/day, prednisolone was tapered and discontinued under introduction of benralizumab for her severe asthma. However, 8 weeks later, symptoms and bilateral patchy infiltrates on chest radiography appeared. Lymphocytosis without eosinophilia was seen in bronchoalveolar lavage fluids, and transbronchial biopsy indicated organizing pneumonia. Cryptogenic organizing pneumonia (COP) was diagnosed and resolved with prednisolone at 30 mg/day. Prednisolone was tapered to 3 mg/day without relapse of CEP or COP. This case suggests the overlap and similar pathogenesis of CEP and COP.

The Prognostic Nutritional Index before durvalumab after chemoradiation predict the overall survival in patients with stage III non-small cell lung cancer

BACKGROUND

Adjuvant durvalumab after chemoradiation has become the standard of care for patients with stage III NSCLC, according to the PACIFIC trial. Whether biomarkers before durvalumab for patients with stage III NSCLC showed predictive and prognostic effects remains unknown.

METHODS

This is a retrospective study in the Fujieda Municipal General Hospital between October 2018 and March 2022. We assessed the predictive value of the Prognostic Nutritional Index (PNI) in stage III non-small cell lung cancer (NSCLC) patients treated with durvalumab after chemoradiation.

RESULTS

After applying the inclusion and exclusion criteria, the study included 56 patients for further analysis. The median follow-up period was 17.6 months (range, 3.0-45.4 months). According to receiver operating characteristic curve results, the PNI cutoff value to predict overall survival (OS) was 37.9, with sensitivity and specificity at 67.9% and 67.9%. Accordingly, the patients were divided into low- and high-PNI groups. Patients with the low-PNI group had a significantly shorter progression-free survival compared to the high-PNI group (median, 9.1 vs. 21.3 months, p = 0.032). OS was also shorter in the low-PNI group (median, 19.0 months vs. not reached, p < 0.001). In the multivariate Cox hazards regression analyses, the high-PNI was an independent prognostic factor for OS (hazard ratio, 0.187; 95% confidence interval, 0.046-0.760; p = 0.019).

It seems that PNI could be used as a predictor for OS in patients with stage III NSCLC treated with durvalumab after chemoradiation.KEY MESSAGESInadequate immunocompetence and nutritional status after chemoradiation therapy may result in poor antitumor efficacy of ICIs.Pretreatment immune and nutritional assessment using PNI could be considered an independent predictor for the survival of stage III NSCLC patients treated with durvalumab after chemoradiation therapy.

Idiopathic Fibrotic Nonspecific Interstitial Pneumonia with Cicatricial Organizing Pneumonia and Intraluminal Pulmonary Ossification Containing Bone Marrow

A 72-year-old man presented with bilateral ground-glass opacities in the lower lung fields on chest radiography. Computed chest tomography showed ground-glass opacities and micronodules in both lower lungs. A video-assisted thoracoscopic biopsy of the right lower lung showed homogeneous thickening of the alveolar septa with fibrosis and inflammatory cell infiltration consistent with fibrotic non-specific interstitial pneumonia (fNSIP). Cicatricial organizing pneumonia and intraluminal pulmonary ossification containing bone marrow that was considered to represent dendriform pulmonary ossification. Idiopathic fNSIP was diagnosed. The patient remains stable under antifibrotic treatment.

An autopsy case of disseminated Cunninghamella bertholletiae infection in an immunocompetent patient: a case report

BACKGROUND

Recently, deaths due to mucormycosis in immunocompromised hosts have increased; however, the clinical and pathological features of mucormycosis are not fully understood, especially in view of the associated high mortality and rare incidence in immunocompetent patients.

CASE PRESENTATION

We have described a rare autopsy case of a 67-year-old Japanese man with chronic obstructive pulmonary disease who contracted mucormycosis. He had not been on any immunosuppressants, and his immune functions were intact. Since 3 days prior to admission to our hospital, he had experienced progressive dyspnea, productive cough, and fever. Chest computed tomography revealed pleural effusion in the left lower hemithorax and consolidation in the right lung field. Although he was administered with tazobactam-piperacillin hydrate (13.5 g/day), renal dysfunction occurred on the ninth disease day. Therefore, it was switched to cefepime (2 g/day). However, his general condition and lung-field abnormality worsened gradually. Cytological analysis of the sputum sample at admission mainly revealed sporangiophores and unicellular sporangioles, while repeated sputum culture yielded Cunninghamella species. Therefore, he was diagnosed with pulmonary mucormycosis. Liposomal amphotericin B (5 mg/kg/day) was initiated on the 28^th disease day. However, chest radiography and electrocardiography detected cardiomegaly and atrial fibrillation, respectively, and he died on the 37^th disease day. A postmortem examination revealed clusters of fungal hyphae within the arteries of the right pulmonary cavity wall, the subpericardial artery, intramyocardial capillary blood vessels, and the esophageal subserosa vein. Direct sequencing revealed that all fungal culture samples were positive for Cunninghamella bertholletiae.

CONCLUSIONS

Cunninghamella bertholletiae could rapidly progress from colonizing the bronchi to infecting the surrounding organs via vascular invasion even in immunocompetent patients.

The clinical utility of comprehensive measurement of autoimmune disease-related antibodies in patients with advanced solid tumors receiving immune checkpoint inhibitors: a retrospective study

BACKGROUND

The comprehensive measurement of autoimmune disease-related antibodies (Abs) before immune checkpoint inhibitor (ICI) treatment may be useful for predicting the development of immune-related adverse events (irAEs); however, the clinical utility is not well known.

MATERIALS AND METHODS

We retrospectively analyzed patients with advanced solid tumors treated with ICI monotherapy or doublet combination therapy between July 2014 and December 2020 at single institute. Anti-nuclear antibody (ANA), anti-thyroglobulin (Tg) Ab, anti-thyroid peroxidase (TPO) Ab, anti-glutamic acid decarboxylase (GAD) Ab, anti-acetylcholine esterase receptor (AchR) Ab, and platelet-associated immunoglobulin G (PA-IgG) Ab were comprehensively measured for the screening before ICI therapy.

RESULTS

Of 275 registered patients (median age, 70 years; male, 64.4%; Eastern Cooperative Oncology Group performance status of 0 or 1, 88.7%; and prior regimen of 0-1/≥2, 88.7%/11.3%), 128 non-small-cell lung cancer, 35 gastric cancer, 33 head and neck cancer, 24 melanoma, 19 renal cell carcinoma, 13 urothelial carcinoma, 12 esophageal cancer, 5 malignant mesothelioma of pleura, 2 endometrial cancer, and 4 other cancer were included. The number of patients with positive ANA, Tg, TPO, PA-IgG, GAD, and AchR Abs was 52 (24.9%), 38 (14.5%), 11 (10.1%), 6 (3.5%), 5 (2.0%), and 1 (0.5%), respectively. There was no association between the development of any irAEs and Abs positivity, while thyroid dysfunction developed more frequently among patients with than without Tg Ab or TPO Ab (39.5% versus 12.5%, P < 0.01; 45.5% versus 14.3%, P = 0.02).

CONCLUSIONS

The clinical utility of comprehensive measurement of autoimmune disease-related Abs before introduction of ICI therapy was limited for predicting irAE. However, Tg and TPO Abs were risk factors as regards the development of ICI-induced thyroid dysfunction.

Prediction of Postoperative Delirium after Gastrointestinal Surgery Using the Mie Constructional Apraxia Scale

Background

Postoperative delirium (POD) is a transient postoperative complication that occurs after surgical procedures. Risk factors reported for POD include dementia and cognitive decline. The purpose of this study was to identify predictors of POD by examining the use of preoperative neuropsychological tests, including the Mie Constructional Apraxia Scale (MCAS), and patient background factors.

Method

The study was performed as a retrospective cohort study. The subjects were 33 patients (mean age, 75.8 ± 10.9 years; male:female ratio, 26:7) who underwent gastrointestinal surgery at Matsusaka City Hospital between December 2019 and April 2021. Data were collected retrospectively from medical records. The study was started after receiving approval from the institution's ethics committee. The survey items included general patient information, nutritional assessment, surgical information, and neuropsychological tests. Subjects were classified into 2 groups according to the presence or absence of POD. If a significant difference was observed between the 2 groups, the sensitivity, specificity, and area under the curve were calculated using a receiver operating characteristic (ROC) curve.

Result

There were 10 patients in the POD group (male:female ratio, 6:4) and 23 patients in the non-POD group (20:3). The POD group had a shorter education history (p = 0.047) and significantly higher MCAS scores (p = 0.007) than the non-POD group. The ROC curve showed a sensitivity of 90%, a specificity of 69%, and an area under the curve of 0.798 when the MCAS cutoff value was set at 3 points.

Conclusion

Preoperative MCAS results were capable of predicting the occurrence of POD after gastrointestinal surgery. In addition, a relatively short education background was also considered a risk factor for POD.

The Geriatric Nutritional Risk Index and Prognostic Nutritional Index Predict the Overall Survival of Advanced Non-Small Cell Lung Cancer Patients

We aimed to assess the prognostic and predictive significance of pretreatment Geriatric Nutritional Risk Index (GNRI) and Prognostic Nutritional Index (PNI) measurements on advanced non-small cell lung cancer (NSCLC) patients treated with first-line therapy. Patients with advanced NSCLC treated between February 2014 and August 2020 were retrospectively analyzed. The optimal cutoff points for GNRI and PNI were measured with receiver operating characteristic (ROC) curve analysis according to overall survival (OS). The predictive factors for progression-free survival (PFS) and OS were evaluated with univariate and multivariate analyses via the Cox hazards regression. A total of 160 patients were included in the study. Significant differences between the low and high-GNRI or PNI groups were found regarding ECOG-PS. The low-GNRI and low-PNI groups had significantly shorter PFS and OS than the high-GNRI and high-PNI groups. A multivariate analysis using a Cox regression model revealed that the high-GNRI group was an independent prognostic factor of OS and PFS, and the PNI group was an independent prognostic factor of OS. Pretreatment GNRI and PNI may therefore be a potential effective predictor of the survival of advanced NSCLC patients undergoing first-line treatment.

Argon plasma coagulation with atezolizumab and chemoradiation in lung pleomorphic cancer showed a remarkable response: Case report

RATIONALE

Lung pleomorphic carcinoma (LPC) is generally resistant to chemotherapy or radiotherapy. However, a combination of immune checkpoint inhibitors and radiotherapy has a remarkable efficacy against LPC.

PATIENT CONCERNS AND DIAGNOSES

Here, we report the case of a 50-year old man diagnosed with progressive LPC. The tumor invaded the carina and predominantly obstructed the right main bronchus; therefore, a combination of palliative chemoradiotherapy and atezolizumab was initiated. However the trachea was gradually obstructed.

INTERVENTION AND OUTCOME

Argon plasma coagulation (APC) was performed to prevent tumor invasion. After three APC sessions, the tumor showed a necrotic change and was easily excised using biopsy forceps.

LESSONS

A combination of chemoradiotherapy, atezolizumab, and APC showed a good efficacy, and the patient had a good response to atezolizumab maintenance therapy. Multidisciplinary treatments, such as a combination of immune checkpoint inhibitors and APC, could have synergistic efficacy in lung cancer.

Difference in Local Lung Movement During Tidal Breathing Between COPD Patients and Asthma Patients Assessed by Four-dimensional Dynamic-ventilation CT Scan

Background

The validity of four-dimensional dynamic-ventilation CT scan for distinguishing COPD from asthma has not been established.

Purpose

To assess whether four-dimensional dynamic-ventilation CT scan can aid in the diagnosis of COPD by comparing local lung movement during tidal breathing between COPD and asthma.

Patients and Methods

Thirty-three COPD patients (30 males and three females; median age 74; range 44-89 years) and 11 asthma patients (five males and six females; median age 55; range: 32-75 years) underwent whole-lung dynamic-ventilation CT scan. CT data were reconstructed, one respiratory cycle to 10 phases, and in addtion we reconstructed threefold new phase data sets. We then analyzed local lung movement during tidal breathing using unpaired t-tests and chi-squared tests.

Results

The local lung movement in COPD patients was significantly smaller than in asthma patients, especially in the ventral part of the lung. This was so even in patients who had mild emphysema (Goddard score <8).

Conclusion

Quantitative evaluation using four-dimensional dynamic-ventilation CT scan demonstrated that local lung movement during tidal breathing, particularly in the ventral lung, was smaller in COPD than in asthma patients, which may help distinguish COPD from asthma.

A Prediction Equation to Assess Resting Energy Expenditure in Japanese Patients with COPD

Background: Medical nutrition therapy is important in the management of chronic obstructive pulmonary disease (COPD) patients. Determination of resting energy expenditure is essential to define therapeutic goals for medical nutrition. Previous studies proposed the use of equations to predict resting energy expenditure. No prediction equation is currently available for the Japanese population. The objective of this study was to develop an equation to predict resting energy expenditure in Japanese chronic obstructive pulmonary disease patients. To this end, we investigated clinical variables that correlate with the resting energy expenditure. Methods: This study included 102 COPD patients admitted at the Matsusaka Municipal Hospital Respiratory Center. We measured resting energy expenditure by indirect calorimetry and explored the relationship of resting energy expenditure with clinical variables by univariate and stepwise linear regression analysis. Results: The resting energy expenditure by indirect calorimetry was significantly correlated with fat-free mass, body weight, body mass index, height, gender, and pulmonary function test by univariate analysis. In the stepwise linear regression analysis, the fat-free mass, body weight, and age remained significantly correlated with indirect calorimetry’s resting energy expenditure. The fat-free mass, body weight, and age explained 50.5% of the resting energy expenditure variation. Conclusion: Fat-free mass, body weight, and age were significantly correlated with resting energy expenditure by stepwise linear regression analysis, and they were used to define a predictive equation for Japanese COPD patients.

Good response with durvalumab after chemoradiotherapy for epidermal growth factor receptor exon 20 insertion adenocarcinoma: A case report

Epidermal growth factor receptor (EGFR) exon 20 insertion is not associated with sensitivity to EGFR tyrosine kinase inhibitors and chemotherapy. Here, we report the case of a 41-year-old man who presented a right lower lobe nodule and mediastinal lymph node enlargement diagnosed as EGFR exon 20 insertion adenocarcinoma with high-expression programmed cell death ligand 1 (PD-L1). He showed stable disease to chemoradiation treatment at the primary tumor site. However, durvalumab treatment has good response. Non-small cell lung cancer with EGFR exon 20 insertion and high PD-L1 expression may be treated with immunotherapy exposure.

Comparing the risk of hepatitis B virus reactivation between direct-acting antiviral therapies and interferon-based therapies for hepatitis C

Hepatitis B virus (HBV) reactivation has been reported during antihepatitis C treatment in patients with hepatitis C virus (HCV) and HBV co-infection. We aimed to evaluate the frequency and risk factors of HBV reactivation during anti-HCV therapy and compared those between interferon (IFN)-free direct-acting antiviral (DAA) therapies and IFN-based therapies. Three hundred and twenty-two patients with HCV infection receiving anti-HCV therapy were retrospectively screened. The baseline HBV infection statuses of all eligible patients and the HBV-DNA level of all patients with current or previous HBV infection were examined at the end of treatment. In patients with baseline anti-HBs positivity, changes in anti-HBs titre were evaluated. Of 287 patients who met the inclusion criteria, 157 had current (n=4) or previous (n=153) HBV infection; 85 were treated with IFN-free DAA therapies and 72 were treated with IFN-based therapies. Six patients experienced HBV reactivation (n=2) or HBV reappearance (n=4) after IFN-free DAA therapies, while no patient developed HBV reactivation after IFN-based therapies. The risk factors of HBV reactivation or reappearance were DAA therapies and a reduction in anti-HBs titre to <12 mIU mL^-1 by the end of treatment. The decline changes of anti-HBs titre were significantly higher in patients treated with DAA therapies. Although HBV reactivation hepatitis was not observed, three of four patients with HBV reactivation or reappearance after achieving HCV eradication had viremia 8 weeks after completion of therapy. A significant proportion of patients develop HBV reactivation or reappearance without hepatitis after IFN-free DAA therapies. Low levels of anti-HBs and their decrease to <12 mIU mL^-1 after treatment are significant risk factors for HBV reactivation or reappearance.

Micro/extended-nano sampling interface from a living single cell

Single-cell analysis is of increasing importance in many fields, but is challenging due to the ultra-small volumes (picoliters) of single cells. Indeed, analysis of a specific analyte might require the analysis of a single molecule or several molecules. Analytical processes usually include sampling, chemical processing, and detection. Although several papers have reported chemical processing and detection methods for single cells, a sampling method compatible with maintaining the viability of a single cell during sampling has yet to be developed. Here, we propose a femtoliter sampling method from a living single cell using micro/nanofluidic device technology. The sampling of 39 fL of cytoplasm from a single human aortic endothelial cell was demonstrated and its viability after sampling was confirmed.

[Indication and Efficacy of Amniotic Membrane Transplantation Performed under Advanced Medical Healthcare]

PURPOSE

To survey indications and outcomes of amniotic membrane transplantation (AMT) performed under Advanced Medical Healthcare (AMH) in Japan.

METHODS

Questionnaires were sent to 21 facilities performing AMT under AMH from 2010-2012. Diagnosis, effectiveness, and final outcomes were surveyed. Moreover, we retrospectively examined the diagnosis, treatment effectiveness, and final outcomes in all AMTs performed under AMH at Kyoto Prefectural University of Medicine (KPUM) from April 2009 through June 2013.

RESULTS

Clinical data of 311 eyes that underwent AMT under AMH was obtained. Of those, diagnoses included pterygium (n = 148), corneal ulcer/epithelial defect (n = 60), corneal perforation (n = 28), intractable glaucoma (n = 24), and others (n = 51). The surgical outcome was completely or partially successful in 287 eyes (92.3%). The final outcome was effective in 281 eyes (90.4%). A total of 45 eyes of 37 patients underwent AMT under AMH at KPUM. Of those, diagnoses included pterygium (n = 15), recurrence of pterygium (n = 27), and symblepharon (n = 3). The surgical outcome was completely successful in 98% and partially successful in 2%. The final outcome was effective in all cases.

CONCLUSION

AMT performed under AMH in Japan was most common in eyes with pterygium, and was highly effective in these cases, as well as corneal ulcer/epithelial defect, corneal perforation, and intractable glaucoma.

Lymphotropic hepatitis C virus has an interferon-resistant phenotype

Hepatitis C virus (HCV) infects and associates with B cells, leading to abnormal B-cell activation and development of lymphoproliferative and autoimmune disorders. This immune perturbation may in turn be associated with the resistance of HCV against the host immune system. The objective of this study was to analyse the effects of HCV infection of B cells on the efficacy of interferon (IFN)-based therapy. The study enrolled 102 patients with chronic hepatitis C who were treated with pegylated IFN plus ribavirin. HCV RNA titres in B cells were compared in patients with rapid viral responder (RVR) vs non-RVR, sustained viral responder (SVR) vs non-SVR and null viral responder (NVR) vs VR. The levels of HCV RNA in B cells were significantly higher in non-RVR, non-SVR and NVR groups. Association between the therapy outcome and the positive B-cell HCV RNA was also investigated in relation to other known viral and host factors. Multivariable analyses showed that the positive B-cell HCV RNA and the minor single-nucleotide polymorphism near the IL28B gene (rs8099917) were independent factors associated with NVR in patients infected with HCV genotype 1. When these two factors were combined, the sensitivity, specificity, positive and negative predictive values for NVR were 92.3%, 98.2%, 92.3% and 98.2%, respectively. Genotype 1 and the presence of one or no mutations in the IFN-sensitivity determining region were associated with higher levels of B-cell HCV RNA. B-cell-tropic HCV appears to have an IFN-resistant phenotype. B-cell HCV RNA positivity is a predictive factor for resistance to IFN-based therapy.

Thin-section CT findings of patients with acute Streptococcus pneumoniae pneumonia with and without concurrent infection

OBJECTIVES

The aim of this study was to compare the pulmonary thin-section CT findings of patients with acute Streptococcus pneumoniae pneumonia with and without concurrent infection.

METHODS

The study group comprised 86 patients with acute S. pneumoniae pneumonia, 36 patients with S. pneumoniae pneumonia combined with Haemophilus influenzae infection, 26 patients with S. pneumoniae pneumonia combined with Pseudomonas aeruginosa infection and 22 patients with S. pneumoniae pneumonia combined with methicillin-susceptible Staphylococcus aureus (MSSA) infection. We compared the thin-section CT findings among the groups.

RESULTS

Centrilobular nodules and bronchial wall thickening were significantly more frequent in patients with pneumonia caused by concurrent infection (H. influenzae: p<0.001 and p<0.001, P. aeruginosa: p<0.001 and p<0.001, MSSA: p<0.001 and p<0.001, respectively) than in those infected with S. pneumoniae alone. Cavity and bilateral pleural effusions were significantly more frequent in cases of S. pneumoniae pneumonia with concurrent P. aeruginosa infection than in cases of S. pneumoniae pneumonia alone (p<0.001 and p<0.001, respectively) or with concurrent H. influenzae (p<0.05 and p<0.001, respectively) or MSSA infection (p<0.05 and p<0.05, respectively).

CONCLUSIONS

When a patient with S. pneumoniae pneumonia has centrilobular nodules, bronchial wall thickening, cavity or bilateral pleural effusions on CT images, concurrent infection should be considered.

Transcriptional activation of the anchoring protein SAP97 by heat shock factor (HSF)-1 stabilizes K(v) 1.5 channels in HL-1 cells

BACKGROUND AND PURPOSE

The expression of voltage-dependent K⁺ channels (K_v) 1.5 is regulated by members of the heat shock protein (Hsp) family. We examined whether the heat shock transcription factor 1 (HSF-1) and its inducer geranylgeranylacetone (GGA) could affect the expression of K_v1.5 channels and its anchoring protein, synapse associated protein 97 (SAP97).

EXPERIMENTAL APPROACH

Transfected mouse atrial cardiomyocytes (HL-1 cells) and COS7 cells were subjected to luciferase reporter gene assay and whole-cell patch clamp. Protein and mRNA extracts were subjected to Western blot and quantitative real-time polymerase chain reaction.

KEY RESULTS

Heat shock of HL-1 cells induced expression of Hsp70, HSF-1, SAP97 and K_v1.5 proteins. These effects were reproduced by wild-type HSF-1. Both heat shock and expression of HSF-1, but not the R71G mutant, increased the SAP97 mRNA level. Small interfering RNA (siRNA) against SAP97 abolished HSF-1-induced increase of K_v1.5 and SAP97 proteins. A luciferase reporter gene assay revealed that the SAP97 promoter region (from −919 to −740) that contains heat shock elements (HSEs) was required for this induction. Suppression of SIRT1 function either by nicotinamide or siRNA decreased the level of SAP97 mRNA. SIRT1 activation by resveratrol had opposing effects. A treatment of the cells with GGA increased the level of SAP97 mRNA, K_v1.5 proteins and I_Kur current, which could be modified with either resveratrol or nicotinamide.

CONCLUSIONS AND IMPLICATIONS

HSF-1 induced transcription of SAP97 through SIRT1-dependent interaction with HSEs; the increase in SAP97 resulted in stabilization of K_v1.5 channels. These effects were mimicked by GGA.

Meticillin-resistant Staphylococcus aureus and meticillin-susceptible S. aureus pneumonia: comparison of clinical and thin-section CT findings

OBJECTIVES

The purpose of this study was to compare the clinical and thin-section CT findings in patients with meticillin-resistant Staphylococcus aureus (MRSA) and meticillin-susceptible S. aureus (MSSA).

METHODS

We retrospectively identified 201 patients with acute MRSA pneumonia and 164 patients with acute MSSA pneumonia who had undergone chest thin-section CT examinations between January 2004 and March 2009. Patients with concurrent infectious disease were excluded from our study. Consequently, our study group comprised 68 patients with MRSA pneumonia (37 male, 31 female) and 83 patients with MSSA pneumonia (32 male, 51 female). Clinical findings in the patients were assessed. Parenchymal abnormalities, lymph node enlargement and pleural effusion were assessed.

RESULTS

Underlying diseases such as cardiovascular were significantly more frequent in the patients with MRSA pneumonia than in those with MSSA pneumonia. CT findings of centrilobular nodules, centrilobular nodules with a tree-in-bud pattern, and bronchial wall thickening were significantly more frequent in the patients with MSSA pneumonia than those with MRSA pneumonia (p = 0.038, p = 0.007 and p = 0.039, respectively). In the group with MRSA, parenchymal abnormalities were observed to be mainly peripherally distributed and the frequency was significantly higher than in the MSSA group (p = 0.028). Pleural effusion was significantly more frequent in the patients with MRSA pneumonia than those with MSSA pneumonia (p = 0.002).

CONCLUSIONS

Findings from the evaluation of thin-section CT manifestations of pneumonia may be useful to distinguish between patients with acute MRSA pneumonia and those with MSSA pneumonia.

Nonstructural protein 3-4A: the Swiss army knife of hepatitis C virus

Hepatitis C virus (HCV) nonstructural protein 3-4A (NS3-4A) is a complex composed of NS3 and its cofactor NS4A. It harbours serine protease as well as NTPase/RNA helicase activities and is essential for viral polyprotein processing, RNA replication and virion formation. Specific inhibitors of the NS3-4A protease significantly improve sustained virological response rates in patients with chronic hepatitis C when combined with pegylated interferon-α and ribavirin. The NS3-4A protease can also target selected cellular proteins, thereby blocking innate immune pathways and modulating growth factor signalling. Hence, NS3-4A is not only an essential component of the viral replication complex and prime target for antiviral intervention but also a key player in the persistence and pathogenesis of HCV. This review provides a concise update on the biochemical and structural aspects of NS3-4A, its role in the pathogenesis of chronic hepatitis C and the clinical development of NS3-4A protease inhibitors.

Mineral trioxide aggregate inhibits osteoclastic bone resorption

Mineral trioxide aggregate (MTA), a commonly used endodontic repair material, is useful for both basic and clinical research, and the effect of MTA on osteoblast differentiation has been well-defined. However, the effects of MTA on osteoclastic bone resorption are not fully understood. Hence, the aim of this study is to examine the effect of MTA solution in the regulation of osteoclast bone-resorbing activity using osteoclasts formed in co-cultures of primary osteoblasts and bone marrow cells. MTA solution dose-dependently reduced the total area of pits formed by osteoclasts. The reduction of resorption induced by 20% MTA treatment was due to inhibition of osteoclastic bone-resorbing activity and had no effect on osteoclast number. A 20% MTA solution disrupted actin ring formation, a marker of osteoclastic bone resorption, by reducing phosphorylation and kinase activity of c-Src, and mRNA expressions of cathepsin K and mmp-9. A high concentration of MTA solution (50%) induced apoptosis of osteoclasts by increasing the expression of Bim, a member of the BH3-only (Bcl-2 homology) family of pro-apoptotic proteins. Taken together, our results suggest that MTA is a useful retrofilling material for several clinical situations because it both stimulates osteoblast differentiation and inhibits bone resorption.

Experiment study on fracture fixation with low rigidity titanium alloy: plate fixation of tibia fracture model in rabbit

In order to investigate bone tissue reaction to the low rigidity titanium alloy of TNTZ in bone plate fixation, animal experiment with rabbit was performed with X-ray follow-up and histological observation. Experimental fractures were made in rabbit tibiae, and fixed by different bone plates of SUS316L, Ti-6Al-4V and TNTZ. Although there was no significant difference in fracture healing, bone atrophy was observed in cortical bone especially under the bone plate, which was different in time course among three materials. The bone atrophy under the bone plate was confirmed as porous or poor bone tissue in histological observation. In addition, the diameter of the tibia bone was increased in TNTZ as the result of bone remodeling with a new cortical bone. It is confirmed that the elastic modulus of the bone plate will naturally influence bone tissue reaction to the bone plate fixation according to the Wolff's law of functional restoration.

Arsenic in various foods: Cumulative data

Data for the arsenic content in various foods were collated. The number of collected values was about 2500 columns, which enables an estimation of the range of arsenic contents in each food group. Data were categorized into six groups (crops, milk/meat/egg, fish, algae, seafood, others) and expressed as a percentile graph. In addition, the inorganic arsenic ratio of each food group was estimated. This approach enabled the authors to understand the arsenic contents of some food groups at a glance. The intake of inorganic arsenic seems to be mostly from seafood. The contribution from other categories of food is small.

Atomic force microscopy dissects the hierarchy of genome architectures in eukaryote, prokaryote, and chloroplast

Because of its applicability to biological specimens (nonconductors), a single-molecule-imaging technique, atomic force microscopy (AFM), has been particularly powerful for visualizing and analyzing complex biological processes. Comparative analyses based on AFM observation revealed that the bacterial nucleoids and human chromatin were constituted by a detergent/salt-resistant 30-40-nm fiber that turned into thicker fibers with beads of 70-80 nm diameter. AFM observations of the 14-kbp plasmid and 110-kbp F plasmid purified from Escherichia coli demonstrated that the 70-80-nm fiber did not contain a eukaryotic nucleosome-like "beads-on-a-string" structure. Chloroplast nucleoid (that lacks bacterial-type nucleoid proteins and eukaryotic histones) also exhibited the 70-80-nm structural units. Interestingly, naked DNA appeared when the nucleoids from E. coli and chloroplast were treated with RNase, whereas only 30-nm chromatin fiber was released from the human nucleus with the same treatment. These observations suggest that the 30-40-nm nucleoid fiber is formed with a help of nucleoid proteins and RNA in E. coli and chroloplast, and that the eukaryotic 30-nm chromatin fiber is formed without RNA. On the other hand, the 70-80-nm beaded structures in both E. coli and human are dependent on RNA.

Autophagy is activated for cell survival after endoplasmic reticulum stress

Eukaryotic cells deal with accumulation of unfolded proteins in the endoplasmic reticulum (ER) by the unfolded protein response, involving the induction of molecular chaperones, translational attenuation, and ER-associated degradation, to prevent cell death. Here, we found that the autophagy system is activated as a novel signaling pathway in response to ER stress. Treatment of SK-N-SH neuroblastoma cells with ER stressors markedly induced the formation of autophagosomes, which were recognized at the ultrastructural level. The formation of green fluorescent protein (GFP)-LC3-labeled structures (GFP-LC3 "dots"), representing autophagosomes, was extensively induced in cells exposed to ER stress with conversion from LC3-I to LC3-II. In IRE1-deficient cells or cells treated with c-Jun N-terminal kinase (JNK) inhibitor, the autophagy induced by ER stress was inhibited, indicating that the IRE1-JNK pathway is required for autophagy activation after ER stress. In contrast, PERK-deficient cells and ATF6 knockdown cells showed that autophagy was induced after ER stress in a manner similar to the wild-type cells. Disturbance of autophagy rendered cells vulnerable to ER stress, suggesting that autophagy plays important roles in cell survival after ER stress.

Analysis of the antigen recognition sites of anti-methamphetamine monoclonal antibodies (II): unique feature of MA-3 antibody

A monoclonal antibody against methamphetamine (MA-3 mAb) was found to be strongly bound to ephedrine. This feature was quite different from that of other fourteen mAbs against MA. Analyses of cDNA sequence and steric conformation by molecular modeling revealed that one hydrophilic pocket was generated in the heavy chain of MA-3 mAb involving CDRH-1 and CDRH-2. Asn33, Asn35, Asn50 and Asp52 were the main components of the unique pocket capable of binding to the hydroxyl group of ephedrine.

Crystallization and preliminary X-ray analysis of the primary receptor (PotD) of the polyamine transport system in Escherichia coli

The primary receptor (potD, M(r) = 39 000) of the polyamine transport system in Escherichia coli has been crystallized by the vapor-diffusion method. Two crystal forms were obtained in the presence of spermidine, and were examined by X-ray analysis. Form I crystals, which diffract to 2.5 A resolution, belong to the space group P2(1), with unit-cell dimensions a = 145.3, b = 69.1, c = 72.5 A and beta = 107.6 degrees. Four molecules are contained in an asymmetric unit. These form two dimers that are related to each other by a local translation of about half of the unit cell along the a axis. The two protein molecules in each dimer are similarly related by a local dyad. Form II crystals diffract to 1.8 A resolution and belong to the space group I4(1), with unit-cell dimensions a = b = 130.3 and c = 38.7 A. They contain one molecule per asymmetric unit.

Genome architecture studied by nanoscale imaging: analyses among bacterial phyla and their implication to eukaryotic genome folding

The proper function of the genome largely depends on the higher order architecture of the chromosome. Our previous application of nanotechnology to the questions regarding the structural basis for such macromolecular dynamics has shown that the higher order architecture of the Escherichia coli genome (nucleoid) is achieved via several steps of DNA folding (Kim et al., 2004). In this study, the hierarchy of genome organization was compared among E. coli, Staphylococcus aureus and Clostridium perfringens. A one-molecule-imaging technique, atomic force microscopy (AFM), was applied to the E. coli cells on a cover glass that were successively treated with a detergent, and demonstrated that the nucleoids consist of a fundamental fibrous structure with a diameter of 80 nm that was further dissected into a 40-nm fiber. An application of this on-substrate procedure to the S. aureus and the C. perfringens nucleoids revealed that they also possessed the 40- and 80-nm fibers that were sustainable in the mild detergent solution. The E. coli nucleoid dynamically changed its structure during cell growth; the 80-nm fibers releasable from the cell could be transformed into a tightly packed state depending upon the expression of Dps. However, the S. aureus and the C. perfringens nucleoids never underwent such tight compaction when they reached stationary phase. Bioinformatic analysis suggested that this was possibly due to the lack of a nucleoid protein, Dps, in both species. AFM analysis revealed that both the mitotic chromosome and the interphase chromatin of human cells were also composed of 80-nm fibers. Taking all together, we propose a structural model of the bacterial nucleoid in which a fundamental mechanism of chromosome packing is common in both prokaryotes and eukaryotes.

Identification of regulatory cis-acting elements for alternative splicing of presenilin 2 exon 5 under hypoxic stress conditions

An alternatively spliced form of the presenilin 2 (PS2) gene lacking exon 5 (PS2V) was found in human brains with sporadic Alzheimer's disease. PS2V was induced by hypoxic stress in human neuroblastoma SK-N-SH cells, indicating that hypoxic stress affects the splicing machineries for PS2 exon 5. Here, we identified the critical cis-acting element (sec 2) on the PS2 pre-mRNA responsible for the aberrant splicing of PS2 exon 5 under hypoxic stress conditions. The element was composed of 23 nucleotides in exon 5 and RNA structural analyses showed a stem-loop structure in this sequence. Treatment with an antisense oligonucleotide directed toward the cis-acting element caused an increase in exon 5 inclusion. These results indicate that the sec 2 identified in this study is a novel regulatory element for exon 5 splicing under stress conditions and that trans-acting factors could specifically bind to the element to skip exon 5 of PS2.

Modulatory effect of fosfomycin on acute inflammation in the rat air pouch model

We examined the effect of fosfomycin (FOM) on the inflammatory response induced by carrageenan in the rat. Air pouches were induced subcutaneously on the backs of rats and injected with carrageenan. The rats were treated with either vehicle or FOM at a dose of 100 mg/kg 1 h before carrageenan challenge. After carrageenan challenge (48 h), the air pouches were removed and analyzed. The volume, protein amounts and cell counts in the exudate obtained from FOM-treated animals were significantly reduced compared with that from vehicle-treated animals. The contents of PGE(2) and TNF-alpha, and mRNA for cyclooxygenase-2 were also markedly suppressed in FOM-treated rats. Histological examination showed suppression of the inflammatory response in the pouch tissues from FOM-treated rats.