Improved diagnostic accuracy with three lung tumor markers compared to six-marker panel

Background

Combining multiple tumor markers increases sensitivity for lung cancer diagnosis in the cost of false positive. However, some would like to check as many as tumor markers in the fear of missing cancer. We though to propose a panel of fewer tumor markers for lung cancer diagnosis.

Methods

Patients with suspected lung cancer who simultaneously underwent all six tests [carcinoembryonic antigen (CEA), cytokeratin-19 fragment (CYFRA), squamous cell carcinoma-associated antigen (SCC), neuron-specific enolase (NSE), pro-gastrin-releasing peptide (ProGRP), and sialyl Lewis-X antigen (SLX)] were included. Tumor markers with significant impact on the lung cancer in a logistic regression model were included in our panel. Area under the curve (AUC) was compared between our panel and the panel of all six.

Results

We included 1,733 [median 72 years, 1,128 men, 605 women, 779 (45%) confirmed lung cancer]. Logistic regression analysis suggested CEA, CYFRA, and NSE were independently associated with the lung cancer diagnosis. The panel of these three tumor markers [AUC =0.656, 95% confidence interval (CI): 0.630-0.682, sensitivity 0.650, specificity 0.662] had better (P<0.001) diagnostic performance than six tumor markers (AUC =0.575, 95% CI: 0.548-0.602, sensitivity 0.829, specificity 0.321).

Conclusions

Compared to applying all six markers (at least one marker above the upper limit of normal), the panel with three markers (at least one marker above the upper limit of normal) led to a better predictive value by lowering the risk of false positives.

Bilateral Pneumothorax after a Transbronchial Lung Cryobiopsy for Interstitial Lung Disease

We herein report a case of bilateral pneumothorax after a unilateral transbronchial lung cryobiopsy (TBLC). A 73-year-old man with no history of cardiothoracic surgery underwent a TBLC for the reevaluation of interstitial lung disease. Five hours later, he developed bilateral pneumothorax, pneumomediastinum, and subcutaneous emphysema. He underwent bilateral chest drainage and was discharged 18 days later. The lung biopsy specimens obtained from the TBLC contained visceral pleura and bronchial cartilage, suggesting bronchial injury as the cause of the bilateral pneumothorax.

ILD-GAP combined with the monocyte ratio could be a better prognostic prediction model than ILD-GAP in patients with interstitial lung diseases

BACKGROUND

The ILD-GAP scoring system is known to be useful in predicting prognosis in patients with interstitial lung disease (ILD). An elevated monocyte count was associated with increased risks of IPF poor prognosis. We examined whether the ILD-GAP scoring system combined with the monocyte ratio (ILD-GAPM) is superior to the conventional ILD-GAP model in predicting ILD prognosis.

METHODS

In patients with ILD treated between April 2013 and April 2017, we were retrospectively assessed the relationships between baseline clinical parameters, including age, sex, Charlson Comorbidity Index score (CCIS), ILD diagnosis, blood biomarkers, pulmonary function test results, and disease outcomes. In ILD patients were included idiopathic pulmonary fibrosis (IPF), idiopathic nonspecific interstitial pneumonia (iNSIP), collagen vascular disease-related interstitial pneumonia (CVD-IP), chronic hypersensitivity pneumonitis (CHP), and unclassifiable ILD (UC-ILD). We also assessed the ability to predict prognosis was compared between the ILD-GAP and ILD-GAPM models.

RESULTS

A total of 179 patients (mean age, 73 years) were assessed. All of them were taken pulmonary function test, including percentage predicted diffusion capacity for carbon monoxide. ILD patients included 56 IPF cases, 112 iNSIP and CVD-IP cases, 6 CHP cases and 5 UC-ILD cases. ILD-GAPM provided a greater area under the receiver-operating characteristic curve (0.747) than ILD-GAP (0.710) for predicting 3-year ILD-related events. Furthermore, the log-rank test showed that the Kaplan-Meier curves in ILD-GAPM were significantly different by stage (P = 0.015), but not by stage in ILD-GAP (P = 0.074).

CONCLUSIONS

The ILD-GAPM model may be a more accurate predictor of prognosis for ILD patients than the ILD-GAP model.

Serum heme oxygenase-1 as a prognostic biomarker in patients with acute exacerbation of interstitial lung disease

Serum heme oxygenase (HO)-1 level has been reported as a clinically reliable diagnostic biomarker for acute exacerbation of interstitial lung disease (ILD); however, its utility for predicting mortality among these patients is unclear. Serum HO-1 levels of patients newly diagnosed with acute exacerbation of ILD were measured at the time of initiating steroid pulse therapy. The relationship between serum HO-1 and various other serum biomarkers, change in HRCT findings, and disease prognosis at 12 weeks after diagnosis of acute exacerbation was evaluated in 51 patients, of whom 17 (33%) had idiopathic pulmonary fibrosis (IPF). Serum HO-1 was higher in patients with acute exacerbation of IPF than in patients with acute exacerbation of other ILDs. Serum HO-1 levels were higher in patients who died within these 12 weeks than in survivors. Among age, sex, comorbidities, IPF diagnosis, HRCT findings, and blood biomarkers, serum HO-1 was a primary predictor of 12-week mortality. In 41 patients who underwent repeat HRCT, serum HO-1 was higher in patients with honeycomb progression than in those without. Serum HO-1 measurement could be useful for evaluating disease mortality and morbidity of patients with acute exacerbation of ILDs.

Safety and Efficacy of Combination Therapy of Remdesivir, Baricitinib, and High-dose Steroids in Patients Hospitalized with Moderate to Severe COVID-19

Objective Dexamethasone, remdesivir (REM), and baricitinib (BAR) are commonly used to treat coronavirus disease 2019 (COVID-19). High-dose steroids have also been reported to be well tolerated, even when used in combination with multiple drugs. In this retrospective study, we assessed the safety and therapeutic efficacy of a three-drug combination of high-dose steroids, REM, and BAR in hospitalized COVID-19 patients. Methods We retrospectively evaluated the safety and efficacy of three-drug combination therapy. Patients We evaluated 107 patients hospitalized with moderate or severe COVID-19 who underwent 3-drug combination therapy with high-dose steroids (80 mg of methylprednisolone or more, REM, and BAR) in our institution from December 2020 to June 2021. The mean age was 62.1±13.7 years old, and 71.2% were men. The severity of the study patients was as follows: 18 (16.8%) with an 8-category ordinal score of 4, 84 (78.5%) with a score of 5, and 5 (4.7%) with a score of 6. Results The frequency of high-grade adverse events was low, except for hyperglycemia (n=59, 45.8%). The median duration from symptom onset to the start of three-drug combination therapy was eight days. All but one of the patients treated with the combination therapy improved. The median time to improvement by 1 category of the eight-category ordinal score was 6 days, and the 28-day mortality was 0.9%. Conclusion This study showed the safety profile of three-drug combination therapy of high-dose steroids, REM, and BAR in moderate to severe COVID-19 patients. The three-drug combination therapy is well tolerated and has the potential to prevent exacerbation of severity.

The clinical impact of comorbidities among patients with idiopathic pulmonary fibrosis undergoing anti-fibrotic treatment: A multicenter retrospective observational study

BACKGROUND

Among patients with idiopathic pulmonary fibrosis (IPF), few studies have investigated the clinical impact of anti-fibrotic treatment (AFT) with and without comorbidities. The aim of the study was to determine whether Charlson Comorbidity Index score (CCIS) can predict the efficacy of AFT in patients with IPF.

METHODS

We retrospectively assessed data extracted from the medical records of IPF patients who received anti-fibrotic agents between 2009 and 2019. The collected data included age, sex, CCIS, pulmonary function test, high-resolution computed tomography (HRCT) pattern, gender/age/physiology (GAP) score, and 3-year IPF-related events defined as the first acute exacerbation or death within 3 years after starting AFT.

RESULTS

We assessed 130 patients (median age, 74 years) who received nintedanib (n = 70) or pirfenidone (n = 60). Median duration of AFT was 425 days. Patients were categorized into high (≥ 3 points) and low (≤ 2 points) CCIS groups. There was no significant difference between the groups in terms of age, sex, duration of AFT, GAP score, or incidence of usual interstitial pneumonia pattern on HRCT except percentage predicted diffusion capacity of lung for carbon monoxide. Also, significant difference was not seen between the groups for 3-year IPF-related events (P = 0.75). Especially, in the low CCIS group but not the high CCIS group, the longer duration of AFT had better disease outcome.

CONCLUSION

In the present study, we could not show any relation between CCIS and IPF disease outcomes in patients undergoing AFT, though the longer duration of AFT might be beneficial for IPF outcomes among patients with low CCIS.

Acute Exacerbation and Proposed Criteria for Progressive Pulmonary Fibrosis in Patients with Fibrotic Hypersensitivity Pneumonitis and Idiopathic Pulmonary Fibrosis

BACKGROUND

Acute exacerbation (AE) occasionally develops in the course of fibrotic hypersensitivity pneumonitis (HP).

OBJECTIVE

The aim of the study was to compare AE of fibrotic HP with that of idiopathic pulmonary fibrosis (IPF).

METHODS

Consecutive patients with pathologically confirmed fibrotic HP and IPF diagnosed based on a multidisciplinary discussion were included in the analysis. AE in patients with fibrotic HP and IPF was evaluated retrospectively.

RESULTS

This study included 309 and 160 patients with fibrotic HP and IPF, respectively. Their 50% survival times were 96.1 and 78.0 months, respectively (hazard ratio [HR]: 0.54 [95% confidence interval, CI: 0.36-0.77], log-rank test; p < 0.001). Notably, the cumulative AE rates of fibrotic HP were 3% at 1 year and 10% at 3 years. Moreover, the corresponding rates of IPF were 8% at 1 year and 20% at 3 years (HR: 0.66 [95% CI: 0.45-0.93], log-rank test; p = 0.034). The 90-day survival rates from the AE onset of fibrotic HP and IPF were 75% and 64%, respectively (HR: 0.51 [95% CI: 0.31-0.83], log-rank test; p = 0.006). The respiratory function test on the physiological criteria of progressive pulmonary fibrosis (PPF) was a predictor of AE in fibrotic HP. However, the high-resolution CT (HRCT) changes in the criteria of PPF were not. Nevertheless, both the physiological and radiological criteria of PPF were a predictor of AE of IPF.

CONCLUSION

AE of fibrotic HP has a lesser prognostic effect than that of IPF. HRCT criteria for PPF were not a risk factor for AE in patients with fibrotic HP.

＜Editors' Choice＞ Comparison of clinical features between patients with acute exacerbation of idiopathic interstitial pneumonia and collagen vascular disease-associated interstitial pneumonia

Acute exacerbation (AE) of interstitial pneumonia (IP) shows poor prognosis, due to the typical histological pattern of diffuse alveolar damage superimposed upon lung fibrosis. The previous reports comparing clinical features between AE of idiopathic interstitial pneumonias (IIPs) and those of IPs with known etiology are limited. We retrospectively compared clinical parameters including age, sex, Charlson Comorbidity Index score (CCIS), blood biomarkers at diagnosis of AE, treatment, and 3-month mortality between patients with AE of IIPs and collagen vascular disease-associated interstitial pneumonia (CVD-IP). We assessed 85 patients, comprising 66 patients with AE of IIPs (78%) and 19 patients with AE of CVD-IP (22%). The least absolute shrinkage and selection operator regression selected CCIS (hazard ratio, 1.281; 95% confidence interval, 1.055-1.556; P = 0.012) and log serum lactate dehydrogenase (LDH) (hazard ratio, 6.267; 95% confidence interval, 2.172-18.085; P < 0.001) as significant predictors of 3-month mortality among these patients. Also, the adjusted survival curves using sex, CCIS, and serum LDH showed no significant differences between these two groups. In conclusion, among AE patients, CCIS and serum LDH level may be more important prognostic factors for 3-month mortality rather than two classification of IP subtypes: IIPs and CVD-IP.

A novel catheter ablation strategy for non-paroxysmal atrial fibrillation combining cryoballoon, radiofrequency, and Marshall-vein ethanol ablations

BACKGROUNDS

Catheter ablation for non-paroxysmal atrial fibrillation (non-PAF) remains challenging and more effective strategy has been required to reduce postoperative arrhythmia recurrences. This study aims to investigate the efficacy and safety of a novel extensive ablation strategy for non-PAF, that is based on a combination of cryoballoon (CBA), radiofrequency (RFA), and Marshall-vein ethanol ablations (EA-VOM).

METHODS

The study was a single-center, retrospective observational study. We enrolled 171 consecutive patients who underwent de-novo catheter ablation for non-PAF under conscious sedation with a novel extensive ablation strategy that included CBA for pulmonary vein isolation (PVI) and left atrial roof ablation (LARA), RFA for mitral isthmus (MI) ablation, superior vena cava isolation, and other linear ablations and EA-VOM. Recurrence of atrial arrhythmias over 1 year, procedure outcomes, and procedure-related complications were investigated.

RESULTS

A total of 139 (81.3%) patients remained in sinus rhythm during 1-year follow-up. Of the 139 patients, 51 patients (29.8%) received antiarrhythmic drugs. The mean procedure time was 204 ± 45 min. PVI and LARA ablation by CBA and MI block by RFA and EA-VOM were completed in 171 (100%) and 166 (97.1%) patients, respectively. No serious procedure-related complications were observed except for one case of delayed pericardial effusion.

CONCLUSION

Approximately 80% of the study patients were AF-free during 1-year follow-up period after a single procedure based on the novel extensive ablation strategy combining CBA, RFA, and EA-VOM. This strategy for non-PAF may be preferred in terms of maintenance of sinus rhythm, safety even in high-risk patients, and relatively short procedure time.

Novel Insights into Microbial Behavior Gleaned Using Microfluidics

Microorganisms develop into communities in nearly every environmental niche, which is typically replete with micrometer-scale gaps and features. In each of these habitats, microorganisms adapt to and are affected by their physical environment. Conventional culture methods use glass bottom dishes or millimeter-scale flow cells, which poorly mimic the complexity of natural micrometer-scale environments; therefore, the limitations associated with the creation of microbe-scale environments with granularity hinder the ability to examine their ecological behavior. Microfluidics is a tool that is increasingly being used to study microorganisms because it enables the manipulation of micrometer-scale flows while simultaneously facilitating real-time and live-cell imaging. In this review, we discuss several insights into the behavior of bacteria and fungi that were gained through the adoption of microfluidics to control complex micrometer-scale environments. We also discuss the potential of the increased adoption of this tool.

Identification of a Novel Gene Involved in Cell-to-cell Communication-induced Cell Death and eDNA Production in Streptococcus mutans

Streptococcus mutans is a major caries-causing bacterium that forms firmly attached biofilms on tooth surfaces. Biofilm formation by S. mutans consists of polysaccharide-dependent and polysaccharide-independent processes. Among polysaccharide-independent processes, extracellular DNA (eDNA) mediates the initial attachment of cells to surfaces. We previously reported that the secreted peptide signal, competence-stimulating peptide (CSP) induced cell death in a subpopulation of cells, leading to autolysis-mediated eDNA release. The autolysin gene lytF, the expression of which is stimulated by CSP, has been shown to mediate CSP-dependent cell death, while cell death was not entirely abolished in the lytF deletion mutant, indicating the involvement of other factors. To identify novel genes involved in CSP-dependent cell death, we herein compared transcriptomes between live and dead cells derived from an isogenic population. The results obtained revealed the accumulation of several mRNAs in dead cells. The deletion of SMU_1553c, a putative bacteriocin gene, resulted in significant reductions in CSP-induced cell death and eDNA production levels from those in the parental strain. Moreover, in the double mutant strain of lytF and SMU_1553c, cell death and eDNA production in response to synthetic CSP were completely abolished under both planktonic and biofilm conditions. These results indicate that SMU_1553c is a novel cell death-related factor that contributes to CSP-dependent cell death and eDNA production.

Usefulness of the over-the-wire microelectrodes catheter in treatment of ventricular arrhythmia arising from the left ventricular summit

BACKGROUND

This study was aimed to investigate efficacy of the over-the-wire (OTW) microelectrodes catheter in coronary venous system (CVS) mapping and treatment of outflow tract ventricular arrhythmia (OTVA) arising from the vicinity of the left ventricular summit (LVS).

METHODS

Consecutive 62 patients with idiopathic OTVA in whom the OTW microelectrodes catheter was routinely used for CVS mapping were analyzed. CVS mapping was performed for both main trunk (from great cardiac vein to anterior interventricular vein) and branches including annular branch or septal branch.

RESULTS

The earliest activation site (EAS) was within the CVS in 21 patients. Among them, the EAS was within the main trunk of the CVS in 7 (33%) and within the branch of the CVS in 14 (67%) patients. Radiofrequency catheter ablation was started at an anatomically adjacent site to the EAS, which eliminated OTVA in 16 (76%) patients　(the endocardial LVOT in 10 and the aortic sinus of Valsalva in 6 patients). For the remaining 5 patients with unsuccessful catheter ablation at an anatomically adjacent site, targeted OTVA was eliminated by catheter ablation at the EAS within the CVS in 2 patients and by chemical ablation with ethanol injection in 1 patient, resulting in overall success rate of 90% (19/21).

CONCLUSION

The OTW microelectrodes-guided ablation of OTVA from the vicinity of the LVS was effective. In maximizing the efficacy of ablation, CVS branch mapping is important since the earliest activation was commonly recorded not in the main trunk but within the branch of the CVS. This article is protected by copyright. All rights reserved.

Heme Oxygenase-1 in Patients With Interstitial Lung Disease: A Review of the Clinical Evidence

The clinical course and rate of progression of interstitial lung disease (ILD) are extremely variable among patients. For the purpose of monitoring disease activity, ILD diagnosis, and predicting disease prognosis, there are various biomarkers, including symptoms, physiological, radiological, and pathological findings, and peripheral blood and bronchoalveolar lavage fluid results. Of these, blood biomarkers such as sialylated carbohydrate antigen, surfactant proteins-A and -D, CC-chemokine ligand 18, matrix metalloprotease-1 and -7, CA19-9, and CA125 have been previously proposed. In the future, heme oxygenase-1 (HO-1) may also become a candidate ILD biomarker; it is a 32-kDa heat shock protein converting heme to carbon monoxide, biliverdin/bilirubin, and free iron to play a role in the pulmonary cytoprotective reaction in response to various stimuli. Recent research suggests that HO-1 can increase in lung tissues of patients with ILD, reflecting anti-inflammatory M2 macrophage activation, and the measurement of HO-1 levels in peripheral blood can be useful for evaluating the severity of lung damage in ILD and for predicting subsequent fibrosis formation.

Serum heme oxygenase-1 measurement is useful for evaluating disease activity and outcomes in patients with acute respiratory distress syndrome and acute exacerbation of interstitial lung disease

Background

Oxidative stress plays an important role in acute lung injury, which is associated with the development and progression of acute respiratory failure. Here, we investigated whether the degree of oxidative stress as indicated by serum heme oxygenase-1 (HO-1) is clinically useful for predicting prognosis among the patients with acute respiratory distress syndrome (ARDS) and acute exacerbation of interstitial lung disease (AE-ILD).

Methods

Serum HO-1 levels of newly diagnosed or untreated ARDS and AE-ILD patients were measured at diagnosis. Relationships between serum HO-1 and other clinical parameters and 1 and 3-month mortality were evaluated.

Results

Fifty-five patients including 22 of ARDS and 33 of AE-ILD were assessed. Serum HO-1 level at diagnosis was significantly higher in ARDS patients than AE-ILD patients (87.8 ± 60.0 ng/mL vs. 52.5 ± 36.3 ng/mL, P <  0.001). Serum HO-1 correlated with serum total bilirubin (R = 0.454, P <  0.001) and serum LDH (R = 0.500, P <  0.001). In both patients with ARDS and AE-ILDs, serum HO-1 level tended to decrease from diagnosis to 2 weeks after diagnosis, however, did not normalized. Composite parameters including serum HO-1, age, sex, and partial pressure of oxygen in arterial blood/fraction of inspired oxygen (P/F) ratio for prediction of 3-month mortality showed a higher AUC (ARDS: 0.925, AE-ILDs: 0.892) than did AUCs of a single predictor or combination of two or three predictors.

Conclusion

Oxidative stress assessed by serum HO-1 is persistently high among enrolled patients for 2 weeks after diagnosis. Also, serum HO-1 levels at the diagnosis combined with age, sex, and P/F ratio could be clinically useful for predicting 3-month mortality in both ARDS and AE-ILD patients.

An autopsy case of ventilator-associated tracheobronchitis caused by Corynebacterium species complicated with diffuse alveolar damage

Ventilator-associated tracheobronchitis (VAT) has been reported to occur in 11% of intubated patients. Corynebacterium spp. can cause lower respiratory infections; however, to our knowledge, there have been no reported cases of VAT caused by Corynebacterium spp. A 55-year-old man was hospitalized with acute respiratory failure after autologous peripheral blood stem cell transplantation for Hodgkin lymphoma. Chest computed tomography showed diffuse ground-glass opacities in both lung fields. A few days after tracheal intubation, steroid pulse, and antibacterial drugs, the patient's pulmonary involvement temporarily improved. However, these opacities rapidly deteriorated, leading to death about 2 weeks after hospitalization. No significant bacteria other than Corynebacterium spp. were detected in sputum cultures during treatment and in blood culture at autopsy. Histological findings revealed tracheitis and diffuse alveolar damage. According to these findings, we diagnosed the patient as having VAT caused by Corynebacterium spp. This report suggests that Corynebacterium spp. might be an important causative pathogen of VAT in immunodeficient patients who undergo tracheal intubation. Additionally, optimal treatment for Corynebacterium spp. must be determined.

Afatinib + bevacizumab combination therapy in EGFR-mutant NSCLC patients with osimertinib resistance: Protocol of an open-label, phase II, multicenter, single-arm trial

Introduction

As most patients with epidermal growth factor receptor (EGFR)‐mutant non‐small cell lung cancer (NSCLC) develop progressive disease after treatment with osimertinib, it is important to develop more effective treatment options. Afatinib has been shown to be more effective in in vitro studies than osimertinib when used in cancer cell lines containing some specific EGFR mutations. Therefore, afatinib may be an effective solution, especially when used in combination with an anti‐VEGF agent such as bevacizumab.

Methods

A phase II multicenter, open‐label, single‐arm trial has been initiated to evaluate the efficacy and safety of afatinib and bevacizumab combination as salvage therapy for EGFR‐mutated lung cancer in patients previously treated with osimertinib. The primary endpoint will be the objective response rate (ORR) and secondary endpoints are progression‐free survival (PFS), overall survival (OS), disease control rate (DCR), and adverse events (AEs).

Discussion

A previous study indicated that afatinib inhibits lung cancer cells with specific EGFR mutations more effectively than other EGFR‐TKIs such as osimertinib. Therefore, we expect that combination therapy using afatinib and bevacizumab will be effective in patients previously treated with osimertinib (registration no. jRCTs031190077).

[A Case of Significant Ejection Fraction Reduction and Heart Failure Induced by Osimertinib]

BACKGROUND

In recent years, osimertinib has been increasingly used as a therapeutic drug for epidermal growth factor receptor(EGFR)mutation-positive lung cancer, with heart failure rarely reported as an adverse event. We report here a case of a significantly decreased ejection fraction and heart failure that were induced by osimertinib. We consider the case important and include a discussion of relevant previous reports.

CASE

The patient was a 73-year-old woman who had been on oral gefitinib as first-line treatment for EGFR mutation-positive(exon19 deletion)non-small cell lung cancer for approximately 1 year and 2 months. Thereafter, she tested positive for an EGFR resistance mutation(T790M); and accordingly, oral osimerti- nib was started at 80mg/day as second-line treatment. After continuing this treatment for 6 months with no particular adverse events, she visited our hospital and was found to have dyspnea on exertion and increased pleural effusion. Based on these findings, cancer relapse was suspected, and the patient was hospitalized for detailed examinations. She was diagnosed with heart failure based on the elevated BNP level that was found in a blood test and CT and echocardiography findings, and her ejection fraction deteriorated to 19% from a pretreatment level of 59%. The conditions improved after diuretic and b- blocker treatment. Given the absence of any possible cause of heart failure or reduced ejection fraction in her past history of illness and medication, we concluded that these conditions were induced by osimertinib.

CONCLUSION

While heart failure induced by EGFR-TKIs has been rarely reported, osimertinib may cause cardiomyopathy due to human epidermal growth factor receptor type 2(HER2)inhibitory activity.

The inhibitory effects of polypyrrole on the biofilm formation of Streptococcus mutans

Streptococcus mutans primary thrives on the biofilm formation on the tooth surface in sticky biofilms and under certain conditions can lead to carious lesions on the tooth surface. To search for a new preventive material for oral biofilm-associated diseases, including dental caries, we investigated the effects of polypyrrole, which contains an electrochemical polymer and causes protonation and incorporation of anion under low pH condition, on the biofilm formation of S. mutans and other streptococci. In this study, polypyrrole was applied in biofilm formation assays with the S. mutans strains UA159 and its gtfB and gtfC double mutant (gtfBC mutant), S. sanguinis, S. mitis and S. gordonii on human saliva and bovine serum albumin-coated 96-well microtiter plates in tryptic soy broth supplemented with 0.25% sucrose. The effects of polypyrrole on biofilm formation were quantitatively and qualitatively observed. High concentrations of polypyrrole significantly inhibited the biofilm formation of S. mutans UA159 and S. sanguinis. As an inhibition mechanism, polypyrrole attached to the surface of bacterial cells, increased chains and aggregates, and incorporated proteins involving GTF-I and GTF-SI produced by S. mutans. In contrast, the biofilm formation of gtfBC mutant, S. sanguinis, S. mitis and S. gordonii was temporarily induced by the addition of low polypyrrole concentrations on human saliva-coated plate but not on the uncoated and bovine serum albumin-coated plates. Moreover, biofilm formation depended on live cells and, likewise, specific interaction between cells and binding components in saliva. However, these biofilms were easily removed by increased frequency of water washing. In this regard, the physical and electrochemical properties in polypyrrole worked effectively in the removal of streptococci biofilms. Polypyrrole may have the potential to alter the development of biofilms associated with dental diseases.

SMU.940 regulates dextran-dependent aggregation and biofilm formation in Streptococcus mutans

The oral bacterium Streptococcus mutans is the principal agent in the development of dental caries. Biofilm formation by S. mutans requires bacterial attachment, aggregation, and glucan formation on the tooth surface under sucrose supplementation conditions. Our previous microarray analysis of clinical strains identified 74 genes in S. mutans that were related to biofilm morphology; however, the roles of almost all of these genes in biofilm formation are poorly understood. We investigated the effects of 21 genes randomly selected from our previous study regarding S. mutans biofilm formation, regulation by the complement pathway, and responses to competence-stimulating peptide. Eight competence-stimulating peptide-dependent genes were identified, and their roles in biofilm formation and aggregation were examined by mutational analyses of the S. mutansUA159 strain. Of these eight genes, the inactivation of the putative hemolysin III family SMU.940 gene of S. mutansUA159 promoted rapid dextran-dependent aggregation and biofilm formation in tryptic soy broth without dextrose (TSB) with 0.25% glucose and slightly reduced biofilm formation in TSB with 0.25% sucrose. The SMU.940 mutant showed higher expression of GbpC and gbpC gene than wild-type. GbpC is known to be involved in the dextran-dependent aggregation of S. mutans. An SMU.940-gbpC double mutant strain was constructed in the SMU.940 mutant background. The gbpC mutation completely abolished the dextran-dependent aggregation of the SMU.940 mutant. In addition, the aggregation of the mutant was abrogated by dextranase. These findings suggest that SMU.940 controls GbpC expression, and contributes to the regulation of dextran-dependent aggregation and biofilm formation.

Inhibiting effects of fructanase on competence-stimulating peptide-dependent quorum sensing system in Streptococcus mutans

Streptococcus mutans produces glucosyltransferases encoded by the gtfB and gtfC genes, which synthesize insoluble glucan, and both insoluble and soluble glucans by conversion of sucrose, and are known as principal agents to provide strong biofilm formation and demineralization on tooth surfaces. S. mutans possess a Com-dependent quorum sensing (QS) system, which is important for survival in severe conditions. The QS system is stimulated by the interaction between ComD {Receptor to competence-stimulating peptide (CSP)} encoded by the comD and CSP encoded by the comC, and importantly associated with bacteriocin production and genetic competence. Previously, we found enzyme fructanase (FruA) as a new inhibitor for the glucan-dependent biofilm formation. In the present study, inhibiting effects by FruA on glucan-independent biofilm formation of S. mutans UA159, UA159.gtfB^-, UA159.gtfC^-, and UA159.gtfBC^- were observed in sucrose and no sucrose sugars-supplemented conditions using the plate assay. The reduction of UA159.comC^- and UA159.comD^- biofilm formation were also observed as compared with UA159 in same conditions. These results suggested that inhibitions of glucan-independent and Com-dependent biofilm formation were involved in the inhibiting mechanism by FruA. To more thoroughly investigate effects by FruA on the QS system, we examined on CSP-stimulated and Com-dependent bacteriocin production and genetic transformation. FruA inhibited bacteriocin production in collaboration with CSP and genetic transformation in bacterial cell conditions treated with FruA. Our findings show that FruA has multiple effects that inhibit survival functions of S. mutans, including biofilm formation and CSP-dependent QS responses, indicating its potential use as an agent for prevention of dental caries.

Adrenomedullin amidation enzyme activities in hypertensive patients

Adrenomedullin (AM) is a potent vasodilating peptide secreted from the vasculature of various organs. It is biologically active when its C-terminus is amidated. Recently, an RIA method was developed for measurement of the active form of AM, or mature AM. We here employed this method to investigate the significance of amidation of AM in controlling cardiovascular function. Thirty-six patients under hemodialysis were recruited and divided into hypertensive (n = 25; 157/86 mmHg) and normotensive (n= 11; 116/66 mmHg) groups. Mature AM, immature AM and blood pressure were monitored during hemodialysis in all patients. There was a significant reduction in blood pressure during hemodialysis in both groups, although after hemodialysis blood pressure was still higher in hypertensives than in normotensives (139 +/-14.8/76 +/- 2.5 mmHg vs. 110 +/- 5.1/66.7 +/- 3.1 mmHg). Mature AM before hemodialysis were lower in hypertensives than normotensives and it decreased in both groups. Although mature AM decreased more in normotensives than in hypertensives (-27 +/- 8% vs. -17 +/- 5%), at the end point, its level was still higher in normotensives. The ratio of mature AM/immature AM decreased only in normotensives (-11.4 8.7%), whereas it remained stable in hypertensives (0.2 +/- 5.6%). Both groups showed similar changes in ANP, endothelin, catecholamines, cGMP, and NOx. The low level in mature AM level in hypertensives may have contributed to the higher blood pressure in this group. The attenuation of AM amidation in normotensives indicates that an unspecified amidative enzyme of AM was regulated in order to normalize blood pressure.

Bone marrow transplantation attenuates murine IgA nephropathy: role of a stem cell disorder

BACKGROUND

The pathogenesis of IgA nephropathy is still obscure. The aim of this study was to investigate whether the fundamental pathogenesis of IgA nephropathy lies in bone marrow stem cells (BMCs).

METHODS

We used donors of two different strains for bone marrow transplantation (BMT) into mice with a high content of serum IgA (ddY strain, HIGA mice), a murine model of IgA nephropathy. One group (B6-->HIGA, N = 5) received BMCs of C57BL/6j (B6) mice, and the other (HIGA-->HIGA, N = 8) were reconstituted with BMCs of HIGA mice.

RESULTS

Twenty-six weeks after BMT, in B6-->HIGA mice, mesangial deposits of IgA and C3 were statistically milder than those in HIGA-->HIGA mice. Light microscopic observations disclosed that glomerular sclerosis and mesangial matrix expansion in B6-->HIGA mice were decreased compared with those in HIGA-->HIGA mice. These B6-->HIGA mice also excreted less urinary albumin than HIGA-->HIGA mice. Furthermore, serum levels of IgA in B6-->HIGA mice were markedly lower than those in HIGA-->HIGA mice. Size analysis of serum IgA revealed that macromolecular IgA were notably lower in B6-->HIGA mice than in HIGA-->HIGA mice.

CONCLUSIONS

Our results suggest that qualitative and quantitative changes of serum IgA are determined at the level of stem cells, and that BMT from normal donors can attenuate glomerular lesions in HIGA mice. This approach may offer a new avenue to study the pathogenesis of IgA nephropathy.

Identification of soluble interleukin-4 receptor in rat glomerular epithelial cells(1)

Interleukin (IL)-4, a pleiotropic cytokine involved in many glomerular diseases, is regulated positively by membrane-bound IL-4R (mIL-4R) and negatively by soluble IL-4R (sIL-4R). Because natural sIL-4R has been documented only in mice, we undertook this study in rats to determine whether they, too, express sIL-4R, particularly in kidney cells. A pair of IL-4R primers was designed for this purpose and used in the polymerase chain reaction. As a result, sIL-4R was found not only in rats spleen cells but also in their glomerular epithelial cells (GEC). Sequence analysis revealed that the mRNA of rat sIL-4R has a 75-bp insert sequence. This insert generated a termination TGA codon upstream from the transmembrane region, resulting in formation of the sIL-4R. Subsequent screening of the kidney cDNA library enabled us to obtain the whole 3605-bp cDNA of sIL-4R; the full-length 3530-bp mIL-4R cDNA was also identified as a much longer sequence than previously published. Among the total 39 clones positive for IL-4R, two were confirmed as sIL-4R, and 37 clones were positive for mIL-4R. Next, the translated portion of sIL-4R cDNA was constructed into an expression vector, enabling us to obtain a recombinant sIL4R-myc fusion protein. By using this recombinant sIL-4R, we proved that sIL-4R can antagonize the IL-4-induced proliferation of spleen cells. Present study demonstrated that sIL-4R is expressed in kidney cells and antagonistically functional.

[A case of difficult intubation with tracheobronchial anomaly]

We experienced a case of difficult intubation with tracheobronchial anomaly. A 66-year-old male was scheduled for subtotal esophagectomy. We used a univent bronchial blocker tube (UBT) to separate the lungs because of difficulty with tracheal intubation using a 37 F double lumen tube (DLT). Intraoperatively, we could not separate the lungs due to tracheobronchial anomaly in the right lung, and attempted to change the tube. We could insert a 35 F DLT to the trachea and separate the lungs. In the case of difficult or impossible conventional direct-vision intubation, the use of DLT is a relative contraindication. However, in this case, the separation of the lungs with UBT was difficult because of tracheobronchial anomaly.

ATF-2-binding regulatory element is responsible for the Ly49A expression in murine T lymphoid line, EL-4

To understand the mechanism of Ly49A-expression and its significance in T-cell differentiation, we analyzed the 5'-flanking region of the Ly49A gene in a search for the Ly49A-regulatory element. Since very few known regulatory elements have been found in this region, presumably a novel regulatory sequence(s) could exist. Accordingly, we defined the 13-bp regulatory element, 5'-ATGACGAGGAGGA-3', restricted to Ly49A-expression in EL-4 cells in comparison with two other representative cell lines tested. This element, designated as EL13, proved to be previously undiscovered by homology search and is highly homologous with several virus DNAs. Using EL13 as a probe we have cloned a cDNA encoding a binding protein to EL13. Its deduced nucleotide sequence revealed that EL13-binding protein is almost identical with rat ATF-2. Although ATF-2 is known to bind to cyclic AMP responsive element (CRE), EL13 shares five out of eight nucleotides with this consensus sequence. Our results suggested that ATF-2 may play an important role via binding to EL13 for the expression of Ly49A. These data will provide useful information for understanding T-cell and NK-cell differentiation in murine immune system.

Evidence suggesting the involvement of hematopoietic stem cells in the pathogenesis of IgA nephropathy

To investigate the role of hematopoietic stem cells in the pathogenesis of IgA nephropathy, T-cell-depleted bone marrow cells for IgA nephropathy-prone ddY mice were transplanted into C57BL/6j (B6) mice pretreated with cyclophosphamide. In the 12th week after bone marrow transplantation, transplanted bone marrow cells had successfully regenerated. In B6 recipients of T-cell-depleted allogeneic bone marrow cells for ddY mice ([ddy-->B6]), mesangial IgA and C3 deposits were significantly more intense than those in B6 mice receiving syngeneic bone marrow cells of B6 mice ([B6-->B6]). The serum IgA level in [ddY-->B6] mice was higher than that in [B6-->B6] mice. Molecular profile analysis of serum IgA revealed that the serum concentration of macromolecular IgA was increased in [ddY-->B6], but not in [B6-->B6] mice. These data suggest that disorders programmed at the level of BMCs are involved in the pathogenesis of IgA nephropathy by increasing circulating levels of macromolecular IgA.

[Effects of folic acid supplementation on hyperhomocysteinemia in CAPD patients: effects on unsaturated fatty acids]

Hyperhomocysteinemia has been recognized as one of the risk factors for atherosclerosis and premature vascular disease. Patients on dialysis and end-stage renal disease also manifest high plasma concentrations of homocysteine. We performed this study to evaluate the effects of folic acid supplementation on hyperhomocysteinemia in CAPD patients. Twenty-three CAPD patients (8 males, 15 females, 49.1 +/- 14.2-years-old) dialyzed for 22.7 +/- 19.2 months participated in the study. Daily 5-mg doses of folic acid supplementation for 4 weeks significantly reduced plasma concentrations of total homocysteine (p < 0.01) and serine (p < 0.001). This observation suggests that the reduction of plasma concentrations of total homocysteine results from activation of homocysteine remethylation to methionine. On the other hand, folic acid supplementation also revealed significant correlations between changes in serum concentrations of both dihomo-gamma-linolenic acid and arachidonic acid and changes in plasma concentrations of total homocysteine (r = -0.517, p < 0.05, r = -0.451, p < 0.05, respectively). In addition, serum concentrations of both dihomo-gamma-linolenic acid and arachidonic acid in 11 CAPD patients with hyperhomocysteinemia (> or = 35 micromol/litter) were significantly lower than those of 12 CAPD patients with normohomocysteinemia (< 35 micromol/litter) (p < 0.05, p < 0.05, respectively). Serum concentrations of both dihomo-gamma-linolenic acid and arachidonic acid in CAPD patients with hyperhomocysteinemia increased significantly (p < 0.01, p < 0.05, respectively) and reached similar levels of CAPD patients with normohomocysteinemia, while plasma concentrations of total homocysteine decreased after folic acid supplementation. These findings suggest that correction of hyperhomocysteinemia in patients on dialysis produces an increase in unsaturated fatty acids.

Detection of antibodies to a recombinant gag protein derived from human endogenous retrovirus clone 4-1 in autoimmune diseases

To investigate whether human endogenous retroviruses (HERV) contribute to autoimmune diseases, we prepared a recombinant p30gag protein derived from clone 4-1 of the HERV family, using a baculovirus-vector system. This p30gag protein (CA41B) was approximately 30 kDa, as expected, and reacted with antibodies for p30gag purified from both murine and feline leukemia virus. This result suggested that the antigenic determinant for p30gag was well conserved in CA41B. Analysis of serum antibodies to p30gag in patients with autoimmune diseases was done by Western blotting. CA41B detected anti-p30gag antibodies in 48.3% of systemic lupus erythematosus (SLE) patients, 35.0% of Sjögren's syndrome (SS) patients, and 33.3% of mixed connective tissue disease (MCTD) patients, whereas no anti-p30gag antibodies were found in healthy subjects. This suggested that HERV p30gag or other retroviral p30gag proteins possessing the same antigenic determinant as CA41B may play a role in these diseases. Although detection of antibodies to HERV p30gag in autoimmune diseases is indirect evidence that HERV proteins are involved, this study showed that patients with autoimmune diseases have antibodies to HERV p30gag using a recombinant HERV protein rather than synthetic peptides based on HERV or retroviral proteins of other species.

Abnormal calcium metabolism in myotonic dystrophy as shown by the Ellsworth-Howard test and its relation to CTG triplet repeat length

Myotonic dystrophy (DM) is an autosomal dominant disorder characterized by peculiar clinical features. Its molecular basis is the unstable expansion of a CTG triplet repeat in the gene encoding myotonin protein kinase (Mt-PK), the nucleotide sequence of which has extensive homology to the cyclic AMP (cAMP)-dependent protein kinase gene. Extensive efforts have been made to clarify the signal transduction pathway in which the responsible gene operates, but confirming evidence has yet to be obtained. Because some symptoms in DM are similar to those in hypoparathyroidism, we divided 24 DM patients into two groups on the basis of their serum calcium levels; Group 1, those with normocalcemia (11 patients), and group 2, those with hypocalcemia (13 patients). The highly sensitive parathyroid hormone (HS-PTH) plasma levels in group 1 were within normal limits, whereas those in group 2 were abnormally high. Laboratory findings for the group 2 patients resembled those for pseudohypoparathyroidism (PHP), whereas those for group 1 patients were normal. The Ellsworth-Howard (EH) test was used to determine which type of PHP the group 2 patients belonged to. Both the phosphaturic (delta P) and urinary cAMP (UcAMP) responses were estimated. The delta P responses in group 2 were significantly lower than those in group 1, but their UcAMP responses did not differ. This is evidence that group 2 patients had PHP type II, whereas group 1 patients were normal. We also investigated whether the disease severity differed between the groups. Cataracts, ectopic calcifications, and ossifications, which are associated with PHP, were more frequent in group 2. In addition, the mean IQ in that group was significantly lower. Clinically, the group 2 signs agreed well with those of PHP, whereas for group 1 there was only a slight similarity. These results are additional evidence that the patients in group 2 have abnormal calcium metabolism, the abnormality being in the postadenylate cyclase-cAMP pathway in the renal tubular cells. The degree of (CTG)n expansion, the so-called expanded DNA fragment (EF) size, was determined by standard Southern blot analysis. The allelic EF sizes in both groups were greater than in the healthy controls. Moreover, those in group 2 were significantly longer than those in group 1. We therefore investigated whether EF size is correlated with the serum calcium and plasma PTH levels, the delta P responses in the EH test, and IQ. All these items were significantly correlated with EF size. Our findings show that the expanded DNA fragment size in DM is correlated with the degree of abnormal calcium metabolism.

Genetic variation and interspecific hybridization among natural populations of zoysiagrasses detected by RFLP analyses of chloroplast and nuclear DNA

Genetic variations among 17 accessions of zoysiagrasses collected from natural populations in Japan were investigated by RFLP analyses of chloroplast DNA (cpDNA) and nuclear DNA. These accessions were classified into five species based on morphological characteristics: Zoysia japonica, Z. matrella, Z. tenuifolia, Z. sinica, and Z. macrostachya. On the basis of eight kinds of RFLPs in cpDNAs detected across accessions, six chloroplast genome types (types A-F) were identified. Although type-A cpDNA was shared by five accessions of japonica and four accessions of matrella, derivative cpDNAs of type A, which each arose by a mutation, were identified in one accession of japonica (type B) and in two accessions of matrella (type C). One accession of japonica which showed spikelets similar to those of shapes macrostachya, contained type-F cpDNA as did sinica and macrostachya. The two accessions of tenuifolia each showed a specific cpDNA type, i.e. types D and E. Genetic relationships among the 17 accessions were investigated by the RFLP analyses of nuclear DNA with 20 genomic and gene probes. A dendrogram constructed with genetic distances calculated from the RFLP patterns indicated four major groups among them. Six accessions of japonica comprised one group, whereas the one accession of japonica possessing the type-F cpDNA was clustered with macrostachya and sinica. Four accessions of matrella with type A cpDNA constituted another group in the dendrogram, showing a closer relationship to the japonica accessions than to the other two accessions of matrella. The remaining two accessions of matrella and tenuifolia accessions were grouped together. These data indicate that zoysiagrasses distributed in Japan harbor highly genetic variations, and that interspecific hybridization has occurred in natural populations.

Differentiated phenotype of glomerular mesangial cells in nodular culture

Prolonged culture of glomerular mesangial cells forms nodular structures composed of cells and surrounding extracellular matrix (ECM), which may mimic the situation in the glomerular mesangium of the kidney. The aim of this study was to investigate whether nodule-associated cells (NAC) exhibit a different phenotype to nodule-unassociated cells (NUC) in vitro. As phenotypic markers for rat mesangial cells, we examined mitogenic activity, expression of alpha-smooth muscle actin, and production of ECM constituents. Autoradiographic and immunohistochemical analyses revealed that NAC showed far less mitogenesis that NUC, like mesangial cells in the normal glomerulus. Immunofluorescence study and Northern blot analysis showed that alpha-smooth muscle actin, a marker of mesangial cell activation/dedifferentiation, was strongly expressed in NUC but faint in NAC. When nodules were dissolved by trypsinization, the dispersed NAC regained both active mitogenesis and alpha-smooth muscle actin expression, suggesting that the altered phenotype was reversible. Northern blot analysis revealed that the ratio of type IV collagen versus type I collagen expression, a marker of mesangial cell differentiation, was elevated in NAC compared with NUC. This phenotypic shift toward differentiation was associated with upregulation of transforming growth factor-beta 1. These findings demonstrate that mesangial cells in nodules exhibit a phenotype which is distinct from that of cells in two-dimensional cultures. We hypothesize that, as a differentiated feature, cultured mesangial cells have the ability to create an appropriate three-dimensional cyto-architecture that resembles the glomerular mesangium.

Reconstitution of SCID mouse with tonsillar cells from patients with IgA nephropathy

IgA nephropathy (IgAN) is characterized by a predominant IgA deposition to the renal mesangium. Immunological abnormalities are closely related to the occurrence and progression of IgAN. Many reports have indicated that tonsillectomy favours the clinical course of IgAN. To understand the role of tonsil glands in the occurrence and progression of IgAN, we injected tonsillar lymphoid cells from patients with IgAN into severe combined immuno-deficient mice (SCID). Tonsillar glands were obtained surgically from 3 patients with IgAN (experimental group) and from 7 patients with chronic tonsillitis without any manifestation of renal diseases (control group). Tonsils were homogenized and resultant cells cryopreserved. On the day of injection, cells were thawed and passed through Ficoll-Paque gradients to obtain mononuclear cells. Fifty million cells were injected intraperitoneally into the SCID mice. After 8 weeks, transferred cells successfully reconstituted SCID, as shown by the fact that human immunoglobulins were detected in the sera of both groups. Renal histopathological examination revealed there was no IgA deposition to the mesangial area in either group. These results indicate that tonsillar mononuclear cells alone may not directly relate to the occurrence of IgAN.

Role of the deletion of polymorphism of the angiotensin converting enzyme gene in the progression and therapeutic responsiveness of IgA nephropathy

Studies conducted over the last decade demonstrated variable therapeutic efficacy of angiotensin converting enzyme (ACE) inhibitor on the progression of glomerular diseases, including IgA nephropathy. In this study, among patients with biopsy-proven IgA nephropathy, 53 patients in whom creatinine clearance had been monitored over 5 yr were recruited for study. These patients were classified into two groups according to whether or not renal function had declined as determined by the slope of creatinine clearance against time: group 1 had stable renal function; group 2 had declining renal function (average: -6.7 +/- 1.3 ml/min/yr). 21 of 53 patients were treated with ACE inhibitor and followed for 48 wk. Gene polymorphism consisting of insertion (I) or deletion (D) of a 287-bp DNA fragment (presumed to be a silencer element) of the ACE gene was determined by PCR. 46 age-matched individuals without history of proteinuria were analyzed as controls. The DD genotype was significantly more frequent in group 2 (43%) than in controls (7%) or group 1 patients with stable renal function (16%). 48 wk after ACE inhibitor administration, proteinuria significantly decreased in patients with DD genotype but not in those with ID or II genotypes. The results indicate that deletion polymorphism in the ACE gene, particularly the homozygote DD, is a risk factor for progression to chronic renal failure in IgA nephropathy. Moreover, this deletion polymorphism predicts the therapeutic efficacy of ACE inhibition on proteinuria and, potentially, on progressive deterioration of renal function.

Expression of an endogenous retroviral gene product in human placenta

To investigate the presence and potential pathophysiological role of endogenous retroviruses in humans, we prepared a recombinant protein using clone 4-I, a proviral sequence. DNA fragments containing the env region of clone 4-I were subcloned into a prokaryotic expression vector (pET3), and 2 fusion proteins, SU413 and SU415, were then expressed in Escherichia coli after treatment with isopropyl-beta-thiogalactopyranoside (IPTG). By sonicating lysates of the transformed E. coli, the recombinant protein SU413 was successfully separated from the native bacterial components, and was used to raise an antiserum in rabbits. In immunoblot analysis, this antiserum specifically recognized the recombinant protein, but did not react with other components of E. coli. This antiserum was then used for an immunofluorescence study of human placenta, in which the env gene transcript has been reported. As a result, the anti-SU413 serum detected substances in syncytiotrophoblasts and vascular endothelia from a human placenta. No such reactivity was detected in human kidney or human liver. Immunoblot analysis revealed that this antiserum reacted to a single molecule of 38-kDa in placenta, and its reactivity was reduced by the antiserum absorbed with SU413 antigen. These findings suggest that human placental syncytiotrophoblasts and vascular endothelia preferentially express a molecule encoded by human endogenous retrovirus clone 4-I.

Heparin selectively inhibits gene expression of matrix metalloproteinase transin in cultured mesangial cells

The aim of this study is to examine the transcriptional regulation of matrix metalloproteinase transin in glomerular mesangial cells responding to inflammatory cytokines and heparin. Northern blot analysis revealed that IL-1 beta preferentially induced transin mRNA. The stimulatory effect was not specific to transin, and upregulation of procollagen alpha 1(IV), laminin B2 and tissue inhibitor of metalloproteinases-1 (TIMP-1) mRNAs was also observed. After IL-1 stimulation, expression of the transin transcript increased progressively for up to 48 hours, differing from the limited induction of procollagen alpha 1(IV) or TIMP-1. When mesangial cells were stimulated by IL-1 beta in the presence of heparin, transin expression was markedly suppressed in a dose-dependent manner. The inhibitory effect of heparin was specific to transin, and induction of procollagen alpha 1(IV), laminin B2 or TIMP-1 by IL-1 beta was not affected. These findings revealed the selective counter regulation by IL-1 beta and heparin of the transin expression in mesangial cells.

An adult case of polycystic kidney disease associated with congenital hepatic fibrosis

Congenital hepatic fibrosis is often associated with infantile, but not with adult polycystic kidney disease. We report the unusual case of an adult patient with polycystic kidney disease complicated by congenital hepatic fibrosis. A 27-year-old women was admitted to our hospital because of gross hematuria due to hemorrhage from renal cysts. She presented hematemesis from ruptured esophageal varices at the age of 14 years. She was diagnosed as having end-stage renal disease due to polycystic kidney disease at the age of 23 years, and maintenance hemodialysis was initiated the following year. Gross hematuria was managed with supportive therapy. However, the patient developed cholangitis and died of sepsis. Postmortem examinations as well as the patient's clinical course suggested that she had an autosomal dominant type of polycystic kidney disease. Histological findings of the liver were compatible with congenital hepatic fibrosis.

[An adult case of glomerulocystic kidney disease]

A 56-year-old female presented with end-stage renal disease. A CT scan of her kidneys demonstrated that the density of the renal parenchyma was quite low as compared with normal kidneys, and that corticomedullary demarcation was obscured. Magnetic resonance imaging (MRI) disclosed low intensity of the kidneys in T1-weighed images, and high intensity in T2-weighed images. In order to elucidate the etiology of her kidney disease, open renal biopsy was performed. The kidney surface was covered with numerous cysts with a diameter of less than 3 mm. Biopsy specimens from the cortical surface showed multiple cystic lesions. Serial sections of more than 200 slices of the biopsy material demonstrated that traces of collapsed glomeruli were present in most of the cysts. On electron microscopy, some epithelial cells lining the cysts were found to be round-shaped and contained a substantial amount of mitochondria, suggesting proximal tubules. These histological findings were compatible with glomerulocystic kidney disease (GCKD). An adult case of GCKD has rarely been reported, but the CT scan as well as MRI of the kidneys appeared to complement the diagnosis of GCKD. Although the cysts of GCKD have been considered to be dilatations of the Bowman's capsules, our observation suggested that part of the cells lining the cysts consisted of proximal tubular epithelium.

Induction of Ly-49 on an interspecies hybridoma between differentiation stage specific murine T cells and a rat T lymphoma

Ly-49 can be expressed in interspecies hybridoma cells resulting from the fusion of Ly-49 negative lymphoid cells from normal mice and Ly-49 negative T cells from the rat thymoma W/Fu(C58NT)D (C58). Several hundred hybridoma clones of this type were studied. Hybridoma clones derived from the fusion between activated C57BL/6 mouse spleen cells and C58 expressed Ly-49 on their surface although Ly-49 was undetectable on both parental cells. No Ly-49 antigen was expressed on hybrids when BW5147, a T lymphoma derived from AKR mouse, replaced C58 as parental cell. Thymocytes from C57BL/6 mice also produced Ly-49 positive interspecies hybridomas with C58. Subsequent manipulation of these thymocytes with a mixture of anti-CD4 and anti-CD8 antibodies plus complement to obtain double negative cells (CD4-/CD8-) prior to the fusion abolished the expression of Ly-49 on hybridomas. On the other hand, if the thymocytes were treated with either anti-CD4 or anti-CD8 antibody plus complement, the resultant thymocytes which were a mixture of cells with a single positive (CD4+/CD8- or CD4-/CD8+) and a double negative phenotype (CD4-/CD8-) retained the ability to produce Ly-49 positive hybridomas. Interspecies hybridomas between either CD4+/CD8- or CD4-/CD8+ functional T cell clones and C58 expressed Ly-49 on their surface, though these parental T cells lacked Ly-49 on their surfaces. Northern hybridization analysis using Ly-49 cDNA revealed that C58 cells do not express Ly-49 mRNA, indicating that a trans-acting factor(s) from C58 plays an important role in the induction of cell surface Ly-49 expression on interspecies hybridomas. Our data indicate the complex nature of the regulatory mechanisms for expression of the Ly-49 molecule.

An autopsy case of light chain deposition disease

This report describes a case of light chain deposition disease (LCDD) with unusual findings of fibrillar structures in the deposits and marked calcification in several organs. A forty-year-old man was initially diagnosed with LCDD in 1987, and died of sepsis three and one-half-years later. Histological examination of autopsy specimens demonstrated eosinophilic amorphous materials, which differed from amyloid, in vessel walls or around parenchymal cells in almost every organ examined. Ultrastructurally, in addition to granular deposits, fibrillar structures were also seen in the deposits. Marked calcification was present in the myocardium, skeletal muscles, adrenal glands and arteries.

Hyperhomocysteinemia as a possible role for atherosclerosis in CAPD patients

It has been shown that hyperhomocysteinemia is a risk factor for atherosclerotic vascular disease. In this study, we measured total plasma homocysteine in continuous ambulatory peritoneal dialysis (CAPD) patients and evaluated its correlation with atherosclerosis. Subjects consisted of healthy volunteers, and hemodialysis (HD) and CAPD patients. Fluoro-HPLC was employed to estimate plasma levels of total homocysteine (Hcy). Plasma levels of total Hcy were significantly higher in the CAPD patients compared with the HD patients and controls. Atherosclerotic score (ASS) was calculated, and the correspondence with plasma levels of total Hcy was analyzed. There was a significant correlation between plasma levels of total Hcy and ASS in CAPD patients. However, plasma levels of total Hcy did not correlate with age, plasma vitamin B6 level, residual renal function, protein catabolic rate (PCR), or KT/V. Our present study suggests that elevated concentrations of total plasma Hcy might play a role in the development of atherosclerosis in CAPD patients.

Neonatal thymectomy diminishes renal IgA deposition in IgA nephropathy-prone ddY mice

To understand the role of thymus-derived T cells in the development of IgA nephropathy (IgAN), we performed neonatal thymectomies on ddY mice, in which this disease occurs spontaneously. Although these thymectomized mice developed a renal lesion closely resembling that typical of IgAN, the extent of their mesangial IgA deposition was significantly milder than in control sham-operated mice. The immunological mechanisms responsible for curbing this mesangial deposition of IgA were then analyzed. The percentage of splenic T cells and the magnitude of mitogenic responses both decreased markedly in thymectomized compared with control mice. These results suggested the hypofunction of thymus-derived T cells. However, serum IgA levels were almost identical in both groups. Furthermore, sera from both groups contained similar amounts of macromolecular IgA, of the type formerly eluted from the affected glomeruli of patients with IgAN. These results strongly indicate that thymus-derived T cells or their products determine the amount of IgA deposited in the kidneys of ddY mice.

The gene encoding mouse lymphocyte antigen Ly-49: structural analysis and the 5'-flanking sequence

Genomic clones encoding the mouse cell-surface antigen, Ly-49, were isolated, and the gene organization was analyzed. The gene spanned approximately 19 kb, and contained seven exons and six introns. The lengths of introns ranged from 1.3 to 8 kb. A 1067-bp sequence in the 5'-flanking region was determined. Primer extension analysis and S1 nuclease mapping revealed a cap site at 158 bp upstream from the ATG coding the N-terminal Met of Ly-49. The 5'-flanking sequence contained a possible promoter sequence, a potential binding site for the T cell-specific transcription factor (TCF-1 alpha/LEF-1), and three sites for the basic helix-loop-helix-binding basic proteins (bHLH). However, no CAAT box-like sequence was present. These results provide important clues for understanding the mechanism of gene expression of lymphocyte antigens.

Renal fibroblasts are sensitive to growth-repressing and matrix-reducing factors from activated lymphocytes

Various forms of nephropathy accompany interstitial fibrosis with lymphocytic infiltration. To probe the relationship between lymphocyte-derived factors and renal fibroblasts, we studied the effect of culture supernatant from lymphocytes stimulated by concanavalin A (ConASN) on the growth and matrix metabolism of rat kidney fibroblasts. 3H-thymidine incorporation and Northern analysis, respectively, revealed that ConASN repressed cell growth and the mRNA level of collagen type I, but dramatically elevated the steady-state expression of metalloproteinase transin/stromelysin. The growth inhibitor in ConASN was moderately heat-sensitive and less than 5 kD in molecular size, qualities that differed from those of transforming growth factor-beta (TGF-beta), IL-1 beta, IL-6, and tumour necrosis factor-alpha (TNF-alpha). The matrix regulatory factor in ConASN was highly heat-sensitive and more than 30 kD in size. Among several lymphokines tested, TNF-alpha produced the same effects as ConASN on the metabolism of extracellular matrix. We hypothesize that lymphocyte-derived factors have a significant role in the attenuation of renal fibrogenesis, as well as its progression, via inhibiting cell growth and matrix accumulation.