Risk and benefit trade-off of thromboprophylaxis in patients with Fontan circulation: insights from the National Database of Health Insurance Claims of Japan

Background

Patients with Fontan circulation are at an increased risk of developing thromboembolic events in the first 3–12 months after surgery [1,2]. Thromboembolic events can lead to significant mortality [3]. The current guidelines recommend the use of antithrombotic therapy, either aspirin or warfarin, as a primary thromboprophylaxis [4,5]. On the other hand, the main adverse effect of thromboprophylaxis is bleeding, which may increase the risk of death. However, there are limited data to assess the outcomes of the thromboembolic and bleeding complications of thromboprophylaxis. Therefore, this retrospective cohort study aimed to evaluate the safety and efficacy of thromboprophylaxis after Fontan surgery.

Methods

We identified 1903 patients who underwent Fontan surgery between June 2011 and September 2019 from the National Database of Health Insurance Claims and Specific Health Checkups of Japan. The patients were followed-up from 2 months to 1 year after Fontan surgery to assess the primary outcomes of thromboembolic and bleeding events. Moreover, we identified the factors associated with primary outcomes in this population using multivariate logistic regression analysis.

Results

A total of 1903 patients (56.1% male) underwent Fontan surgery at a median age of 3 years (1–22); 1815 patients (95.4%) had an extracardiac conduit. No thromboprophylaxis was prescribed to 65 patients (3.4%), whereas 228 patients (12.0%) received aspirin alone, 346 patients (18.2%) received warfarin alone, and 1264 patients (66.4%) received a combination therapy of aspirin and warfarin. In the first post-operative year, thromboembolic events occurred in 234 patients (12.3%) and bleeding events occurred in 202 patients (10.6%). Older age (odds ratio, 1.08; 95% confidence interval, 1.06–1.11) and aspirin use (odds ratio, 0.34; 95% confidence interval, 0.15–0.78) were independently associated with thromboembolic events. In particular, up to 5 months after surgery, the incidence rate of thromboembolism was significantly lower in patients who received aspirin alone (0.9%) than in those who received other thromboprophylaxis regimens (no thromboprophylaxis, 13.8%; warfarin, 7.5%; combination therapy, 7.4%; p<0.05). No significant difference in incidence of bleeding events was observed among the four thromboprophylaxis regimens. A history of postoperative hemorrhage (odds ratio, 1.49; 95% confidence interval, 1.01–2.21) and the use of a potassium channel blocker (odds ratio, 2.12; 95% confidence interval, 1.10–4.05) was associated with a higher risk of bleeding events.

Conclusions

In this study, patients who received aspirin alone showed a significantly lower incidence of thromboembolic events. Aspirin may be useful for preventing thromboembolism a year after Fontan surgery. After Fontan surgery, it is important to select a safe and effective thromboprophylaxis regimen and evaluate the risk factors for thromboembolic and bleeding events in a timely manner.

Funding Acknowledgement

Type of funding sources: None.

A novel germline BMPR1A variant (c.72_73delGA) in a Japanese family with hereditary mixed polyposis syndrome

Hereditary mixed polyposis syndrome (HMPS) is a rare autosomal dominant disorder characterized by a mixture of typical and/or atypical juvenile polyps, adenomas and hyperplastic polyps, resulting in an increased risk of colorectal cancer. In HMPS, four different germline BMPR1A variants from five unrelated families have been reported. This study is the first to report HMPS within a Japanese family. The proband underwent repeated colonoscopic polypectomies over a 5-year period, since the age of 67. Histological examination of these resected polyps revealed adenomas, juvenile-like polyps and hyperplastic changes. Genetic testing was conducted to identify the causative genes for hereditary gastrointestinal cancer syndromes, including BMPR1A. We detected a germline variant, c.72_73delGA, in BMPR1A. The proband’s elder brother, younger sister and nephew have also undergone repeated colonoscopic polypectomies at other clinics. His sister and nephew underwent genetic testing, and the same BMPR1A variant was identified.

An apparatus based on an atomic force microscope for implementing tip-controlled local breakdown

Solid-state nanopores are powerful tools for sensing of single biomolecules in solution. Fabrication of solid-state nanopores is still challenging, however; in particular, new methods are needed to facilitate the integration of pores with larger nanofluidic and electronic device architectures. We have developed the tip-controlled local breakdown (TCLB) approach, in which an atomic force microscope (AFM) tip is brought into contact with a silicon nitride membrane that is placed onto an electrolyte reservoir. The application of a voltage bias at the AFM tip induces a dielectric breakdown that leads to the formation of a nanopore at the tip position. In this work, we report on the details of the apparatus used to fabricate nanopores using the TCLB method, and we demonstrate the formation of nanopores with smaller, more controlled diameters using a current limiting circuit that zeroes the voltage upon pore formation. Additionally, we demonstrate the capability of TCLB to fabricate pores aligned to embedded topographical features on the membranes.

A Novel Diagnostic System for Infectious Diseases Using Solid-State Nanopore Devices

Nanopore-based diagnostic systems are a promising tool for counting viruses in a specimen one by one. However, despite intensive R&D efforts, it remains difficult to recognize virus subtypes by nanopore devices. We thus propose a novel diagnostic system that combines a specialized virus recognition procedure with a nanopore detection procedure. This recognition procedure consists of three steps: 1) capture target viruses using specific probes for recognition; 2) release captured targets; and 3) detect released targets by nanopore. Proof-of-concept tests are conducted using avidin-modified fluorescent particles (as a model for viruses) and biotin-modified alkane thiol (as a model for probes). The avidin-modified particles are confirmed to be captured on electrode by biotin-modified probes and then, the particles are electrochemically released from the electrode. Consequently, the released particles are successfully detected by nanopore devices. Furthermore, the concept is also proved by using human influenza viruses (H1N1, A/PR/8/34) and sugar chain (6'-sialyllactose)-modified probes. This suggests that our concept is applicable to various infectious diseases by changing probes (ligands).

[Dissolution and maintenance of portal vein thrombosis with antithrombin III and edoxaban in liver cirrhosis:a case report]

A male patient in his 70s was referred to our department. He was found to have alcoholic liver cirrhosis, esophageal varices, and portal vein thrombosis. Antithrombin III (ATIII) formulation was administered. The thrombus was almost completely lysed 2 days after administration. Because portal vein thrombosis could recur, edoxaban, a direct oral anticoagulant (DOAC), was introduced to prevent recurrence. After 4 months, he showed no recurrence of portal vein thrombosis. In the present case, the combination of an ATIII formulation as initial treatment and edoxaban as maintenance therapy was safe and effective. The combination of ATIII and edoxaban may be a treatment option for patients with portal vein thrombosis.

Clinical characteristics and prognostic factors of pneumonia in patients with and without rheumatoid arthritis

Background

To elucidate the characteristics of pneumonia in rheumatoid arthritis (RA) patients and to assess whether pneumonia in RA patients differs from that in non-RA patients.

Methods

We retrospectively divided pneumonia patients into two groups, those with RA and those without RA, and compared the two groups. We evaluated the risk factors for mortality with univariate and multivariate logistic regression analysis.

Results

Among 1549 patients, 71 had RA. The RA patients with pneumonia were 71.0±8.9 years old, 54.9% were female, 40.9% had a smoking history, and 71.8% had underlying respiratory disease. Female sex, non-smoker, and respiratory comorbidities were statistically more frequent in the RA patients than non-RA patients. The most frequent causative microbial agents of pneumonia in the RA patients were Streptococcus pneumoniae, Pseudomonas aeruginosa, Haemophilus influenzae, Mycoplasma pneumoniae, and influenza virus, whereas those of pneumonia in non-RA patients were S. pneumoniae, influenza virus, M. pneumoniae, Legionella spp., P. aeruginosa, H. influenzae, and Moraxella catarrhalis. Polymicrobial infection were identified as etiologies more frequently in the RA patients than non-RA patients. Although the severity of pneumonia did not differ between the two groups, mortality was statistically higher in the RA patients than non-RA patients. Multivariate analysis showed RA to be an independent risk factor for mortality.

Conclusions

P. aeruginosa, H. influenzae, M. catarrhalis, and polymicrobial infection were statistically more frequent etiologies of pneumonia in the RA patients than non-RA patients. RA itself was found to be an independent risk factor for mortality from pneumonia.

Heterocyclic boronic acids display sialic acid selective binding in a hypoxic tumor relevant acidic environment

A group of heterocyclic boronic acids demonstrating unusually high affinity and selectivity for sialic acids are described, with strong interactions under the weakly acidic pH conditions associated with a hypoxic tumoral microenvironment.

Boronic acids are well known for their ability to reversibly interact with the diol groups found in sugars and glycoproteins. However, they are generally indiscriminate in their binding. Herein we describe the discovery of a group of heterocyclic boronic acids demonstrating unusually high affinity and selectivity for sialic acids (SAs or N-acetylneuraminic acid), which are sugar residues that are intimately linked with tumor growth and cancer progression. Remarkably, these interactions strengthen under the weakly acidic pH conditions associated with a hypoxic tumoral microenvironment. In vitro competitive binding assays uncovered a significantly higher ability of 5-boronopicolinic acid, one of the derivatives identified in this work as a strong SA-binder, to interact with cell surface SA in comparison to a gold-standard structure, 3-propionamidophenylboronic acid, which has proven to be an efficient SA-binder in numerous reports. This structure also proved to be suitable for further chemical conjugation with a well-preserved SA-binding capability. These findings suggest an attractive alternative to other ongoing boronic acid based chemistry techniques aiming to achieve tumor-specific chemotherapies and diagnoses.

Viper bite during pregnancy: case report

Viper bites in pregnant women have rarely been reported thus far. Moreover, there is no consensus regarding the treatment of such cases. In this paper, the authors report the successful treatment of viper bite during pregnancy without using antivenom.

One-to-one spatially matched experiment and atomistic simulations of nanometre-scale indentation

We have carried out nanoindentation studies of gold in which the indenter is atomically characterized by field-ion microscopy and the scale of deformation is sufficiently small to be directly compared with atomistic simulations. We find that many features of the experiment are correctly reproduced by molecular dynamics simulations, in some cases only when an atomically rough indenter rather than a smooth repulsive-potential indenter is used. Heterogeneous nucleation of dislocations is found to take place at surface defect sites. Using input from atomistic simulations, a model of indentation based on stochastic transitions between continuum elastic-plastic states is developed, which accurately predicts the size distributions of plastic 'pop-in' events and their dependence on tip geometry.

Deterioration of the immune response induced by sulfamethoxazole-trimethoprim in a rheumatoid arthritis patient with Pneumocystis jirovecii pneumonia

A 73-year-old woman with rheumatoid arthritis treated with methotrexate and prednisolone was admitted with dyspnea and ground-glass opacity on chest CT. We diagnosed her with Pneumocystis jirovecii pneumonia (PCP) based on a positive PCR analysis of Pneumocystis jirovecii and the presence of cysts in bronchoalveolar lavage fluid. The PaO2 was 74.7 Torr on room air, and treatment with sulfamethoxazole-trimethoprim only was initiated. The hypoxemia and ground-glass opacity increased on hospital day 3, and the administration of adjunctive steroid therapy resulted in an improvement in the patient's condition. Although patients with PCP with HIV infection and hypoxemia are often treated with adjunctive steroid therapy to prevent adverse immune reactions, the efficacy of additive steroid administration in case of non-HIV PCP has not been established.

Prognostic factors and radiographic outcomes of nontuberculous mycobacterial lung disease in rheumatoid arthritis

OBJECTIVE

The aims of our study were to retrospectively review patients with rheumatoid arthritis (RA) with nontuberculous mycobacterial (NTM) lung disease, to assess the prognostic factors, and to analyze the time to disease deterioration according to the antirheumatic drugs received during the NTM lung disease followup period.

METHODS

We retrospectively analyzed medical records of 98 HIV-negative RA patients with NTM lung disease treated at our institution, and investigated potential risk factors of mortality with Cox regression analysis. Time to radiologic deterioration was evaluated if antirheumatic drugs were not changed during observational periods and computed tomography was performed once each year.

RESULTS

Mean patient age was 67.6 years, and median followup period was 4.4 years. NTM species included Mycobacterium avium complex (83.7%), M. kansasii (6.1%), M. gordonae (6.1%), and others (4.1%). Radiographic features included nodular/bronchiectatic (NB) disease (57.1%), fibrocavitary (FC) disease (14.3%), FC+NB disease (16.3%), and other types (12.2%). Initial management included observation in 74 (75.5%) patients. Negative prognostic factors of mortality were C-reactive protein (CRP) ≥ 1.0 mg/dl and radiographic features of FC, FC+NB, or other disease types. Median time to radiologic deterioration was 3.6 years. Erythrocyte sedimentation rate (ESR) > 50 mm/h was a negative prognostic factor of radiologic deterioration.

CONCLUSION

The most frequent NTM species was M. avium complex. CRP and radiographic features were prognostic factors for all-cause mortality, and ESR was a prognostic factor of radiologic deterioration. Further studies are warranted focusing on time to disease deterioration according to antirheumatic drug received during NTM followup.

Effect of using stencil masks made by focused ion beam milling on permalloy (Ni81Fe19) nanostructures

Focused ion beam (FIB) milling is a common fabrication technique to make nanostencil masks which has the unintended consequence of gallium ion implantation surrounding milled features in silicon nitride membranes. We observe major changes in film structure, chemical composition, and magnetic behaviour of permalloy nanostructures deposited by electron beam evaporation using silicon nitride stencil masks made by a FIB as compared to stencil masks made by regular lithography techniques. We characterize the stenciled structures and both types of masks using transmission electron microscopy, electron energy loss spectroscopy, energy dispersive x-ray spectroscopy, magnetic force microscopy and kelvin probe force microscopy. All these techniques demonstrate distinct differences at a length scale of a 1-100 nm for the structures made using stencil mask fabricated using a FIB. The origin of these differences seems to be related to the presence of implanted ions, a detailed understanding of the mechanism however remains to be developed.

An autopsy case of pulmonary aspergillosis with fungus ball formation in an artificial aortic graft

A 38-year-old man with Marfan syndrome underwent an aortic replacement with an artificial aortic valve at 27 years of age and an aortic graft at 31 years of age. In 2011, he was diagnosed as having chronic necrotizing pulmonary aspergillosis (CNPA). He developed a fever and an increased sputum volume and was admitted to the hospital in 2012. Contrast-enhanced CT showed an irregularly shaped nonenhanced structure in the aortic graft. He died on hospital day 31. From the autopsy findings, we speculated that an infiltration by the CNPA lesion into a pulmonary vein was followed by the hematogenous formation of a fungus ball in the aortic graft.

Etiology and factors contributing to the severity and mortality of community-acquired pneumonia

OBJECTIVE

Community-acquired pneumonia (CAP) remains a major cause of death. No studies have reported the use of rapid influenza diagnostic tests (RIDT) for the etiological diagnosis, and the factors contributing to severity and mortality have not yet been fully investigated. The aim of this study was to review the etiologies of CAP using RIDT and to identify risk factors related to the severity and mortality of the disease.

METHODS

This retrospective study assessed these factors in hospitalized patients, with special emphasis on microbial etiology.

RESULTS

A total of 1,032 patients aged 63.9±18.3 years were studied, 66.2% of whom were men. Microbial identification was obtained in 57.0% of the cases. The most frequent causative microbial agents were Streptococcus pneumoniae, Mycoplasma pneumoniae and the influenza virus, and the second most frequent pathogens in the patients with severe CAP and the non-survivors were S. pneumoniae and the influenza virus. Age (≥65 years), chronic obstructive pulmonary disease, congestive heart failure, diabetes mellitus, dementia and Legionella spp. infection and polymicrobial infection were each found to be independent factors related to severity in the multivariate analysis, whereas "unidentified pathogen" was found to be an independent factor for non-severe CAP. Age (≥65 years), chronic pulmonary aspergillosis, post-lung cancer surgery and severe CAP were found to be independent factors for non-survival according to a multivariate analysis.

CONCLUSION

In addition to S. pneumoniae, the influenza virus was a frequent cause of CAP overall and a frequent causative pathogen in both severe cases of CAP and non-survivors. Legionella spp. infection and polymicrobial infection were found to be an independent factor for the severity of CAP along with advanced age and certain comorbidities. An advanced age, certain respiratory comorbidities and severe CAP were found to be important independent factors for the mortality of CAP.

Anti-TCRβ mAb induces long-term allograft survival by reducing antigen-reactive T cells and sparing regulatory T cells

TCR specific antibodies may modulate the TCR engagement with antigen-MHC complexes, and in turn regulate in vivo T cell responses to alloantigens. Herein, we found that in vivo administration of mAbs specific for mouse TCRβ (H57-597), TCRα or CD3 promptly reduced the number of CD4(+) and CD8(+) T cells in normal mice, but H57-597 mAb most potently increased the frequency of CD4(+) Foxp3(+) Treg cells. When mice were injected with staphylococcal enterotoxin B (SEB) superantigen and H57-597 mAb, the expansion of SEB-reactive Vβ8(+) T cells was completely abrogated while SEB-nonreactive Vβ2(+) T cells remained unaffected. More importantly, transient H57-597 mAb treatment exerted long-lasting effect in preventing T cell responses to alloantigens, and produced long-term cardiac allograft survival (>100 days) in 10 out of 11 recipients. While Treg cells were involved in maintaining donor-specific long-term graft survival, T cell homeostasis recovered over time and immunity was retained against third party allografts. Moreover, transient H57-597 mAb treatment significantly prolonged survival of skin allografts in naïve recipients as well as heart allografts in skin-sensitized recipients. Thus, transient modulation of the TCRβ chain by H57-597 mAb exhibits potent, long-lasting therapeutic effects to control alloimmune responses.

Field deposition from metallic tips onto insulating substrates

The deposition of gold ions from atomic force microscope cantilever tips onto bulk insulating substrates with nearby surface electrodes is discussed. Numerical models of the potential distribution are used to estimate potential barriers for the desorption process. These models indicate deposition height thresholds of 7-10 nm with the tip 20-25 nm from the metallic electrode edge over a KBr surface but greater than 20 nm high for InP/GaAs/InP substrates with a two-dimensional electron gas (2DEG) as the back electrode. Experimental results for the deposition of gold clusters over KBr surfaces near metal electrodes in ultra-high vacuum (UHV) are presented and show promising agreement with calculations of the deposition threshold heights. Deposition of clusters over InP is discussed for comparison and indicates similar trends.

[Clinical study of pneumocystis pneumonia in patients with rheumatoid arthritis]

We reviewed case of pneumocystis pneumonia (PCP) with rheumatoid arthritis. We administered the antirheumatic drug methotrexate (MTX) at the time of to 13 patients, corticosteroids to 11 patients and a tumor necrosis factor (TNF) inhibitor to 3 patients. Treatment for PCP was started on admission in all cases. We administered adrenocorticosteroids to all 13 patients with a PaO2 level < 70 Torr. Three patients were under respiratory management, and 4 patients died. By univariate analysis, prognostic indicators of death were: presence of acute respiratory distress syndrome (ARDS), peripheral blood neutrophil/lymphocyte ratio, serum albumin value, serum beta-D-glucan value, and AaDO2 and PaO2/FiO2 ratios. Readministration of a TNF inhibitor in 2 patients and MTX in 3 patients was possible after PCP remission. Even though we began treatment for PCP on the day of admission, 25% of patients died. PCP may occur in patients who are given MTX or a TNF inhibitor or both, and the clinician should endeavor to detect its onset as early as possible. Elucidation of the prognostic indicators of recovery may require multivariate analysis of many cases.

[Case of novel influenza A (H1N1) pneumonia with shrinkage of a pulmonary lesion]

Fever developed in a 56-year-old man with sarcoidosis and bronchial asthma, and influenza was diagnosed. He was given zanamivir on the day of diagnosis, but he suffered a bronchial asthma attack 4 days after the diagnosis of influenza, and pneumonia developed 7 days subsequently. He was then admitted to our hospital. A rapid antigen test was positive for influenza type A, and reverse-transcriptase polymerase chain reaction results were also positive for novel influenza A (H1N1). Chest computed tomography showed homogeneous ground-glass opacities in bilateral lung fields, and novel influenza A (H1N1) pneumonia was diagnosed. The patient was treated with oseltamivir and steroid therapy for the bronchial asthma attack; however, ground-glass opacities enlarged and became consolidated. The lower lobes of both lungs showed shrinkage and persistent volume loss. Improvement in the consolidation was accompanied by improvement in his respiratory condition. We report a case with an interesting radiological course.

Lung diseases directly associated with rheumatoid arthritis and their relationship to outcome

The outcome and cause of death of each lung disease directly associated with rheumatoid arthritis (RA-LD) have been poorly investigated. A retrospective study was conducted of 144 patients with RA-LD, in whom the median follow-up period after the initial visit for a respiratory examination was 4.5 yrs. A total of 57 patients were identified with usual interstitial pneumonia (UIP), 31 with bronchiectasis, 16 with nonspecific interstitial pneumonia (NSIP), 11 with bronchiolitis, five with organising pneumonia (OP), five with diffuse alveolar damage (DAD) and 19 with combined disease. The 5-yr survival rates were 36.6% in the UIP group, 87.1% in the bronchiectasis group, 93.8% in the NSIP group, 88.9% in the bronchiolitis group, 60.0% in the OP group and 20.0% in the DAD group. Survival of patients with DAD was worse than that of patients with UIP. Overall, survival of patients with UIP was worse than that of patients with bronchiectasis, NSIP or bronchiolitis. Of the 144 patients, 71 (49.3%) died, of whom 58 (81.7%) died due to respiratory lesions. Of patients with RA-LD, patients with DAD experienced the highest mortality, and the survival of patients with UIP was worse than that of patients with NSIP.

The effect of emphysema on lung function and survival in patients with idiopathic pulmonary fibrosis

BACKGROUND AND OBJECTIVE

In this study the prevalence, lung function and prognosis of IPF combined with emphysema were evaluated.

METHODS

Consecutive patients with usual interstitial pneumonia (UIP) on high-resolution computed tomography (HRCT), with or without emphysema, were assessed retrospectively. The area of fibrosis in the base of the lungs was assessed by HRCT as minimal (<2 cm from the subpleura), moderate (>or=2 cm from the subpleura, <1/3 of the area of the base of the lungs) or severe (>or=1/3 of the area of the base of the lungs).

RESULTS

Among 660 patients with UIP on HRCT, 221 showed upper-lobe emphysema. Pulmonary function results for patients with UIP and UIP/emphysema, respectively, were: FVC, 71.8% and 87.1%; FEV1%, 86.7% and 87.9%; and DL(CO), 74.3% and 65.2% of predicted. The relationship between FVC, the extent of fibrosis and survival was investigated in 362 patients with records of pulmonary function tests and no lung cancer at the time of entry into the study. Although the extent of fibrosis was similar between the groups, 71.3% of UIP patients met the lung volume criteria for IPF (FVC <80% of predicted), whereas only 26.5% of UIP/emphysema patients met the lung volume criteria for IPF. Median survival was 7.5 years in the UIP group and 8.5 years in the UIP/emphysema group.

CONCLUSIONS

Emphysema was a common finding in patients with UIP. Patients with UIP and emphysema had greater lung volumes and better survival compared with those with UIP alone.

Clinical characteristics of acute pulmonary thromboembolism in Japan: results of a multicenter registry in the Japanese Society of Pulmonary Embolism Research

BACKGROUND

Although the incidence of acute pulmonary thromboembolism (APTE) has been increasing in Japan, patient characteristics, management strategies, and outcome have not yet been assessed in large series.

HYPOTHESIS

The present study was designed to investigate the current status of APTE in Japan.

METHODS

Of a total of 533 registry patients with pulmonary thromboembolism, 309 with APTE were analyzed with respect to clinical symptoms and signs, predisposing factors, diagnostic procedures, estimation of deep venous thrombosis, treatment, and clinical course.

RESULTS

Main risk factors were recent major surgery, cancer, prolonged immobilization, and obesity; only a few patients had coagulopathy and 36% were in cardiogenic shock at presentation. The majority of registry patients underwent lung scans or pulmonary angiography; 30% were diagnosed only by lung scanning. Venous ultrasonography was used in only 34 patients, while 188 patients underwent at least one diagnostic procedure for deep venous thrombosis. Thrombolysis was more frequently performed in patients with cardiogenic shock, and only a few patients received thromboembolectomy. In-hospital mortality rate was 14%. In patients with cardiogenic shock, the mortality rate was reduced by thrombolysis. The predictors of in-hospital mortality were male gender, cardiogenic shock, cancer, and prolonged immobilization.

CONCLUSIONS

The patients in this registry had almost the same findings as those in Western patients, except for some points that had the possibility of demonstrating a difference between Westerners and Japanese in the development of APTE. These results can prove especially helpful in planning prospective, randomized trials that will clarify the impact of widely used treatment modalities on the outcome of patients with APTE.

High Q optical fiber tips for NC-AFM in liquid

Non-contact atomic force microscopy is rapidly expanding from ultra-high vacuum to include the study of surfaces and biomolecules in liquids by high resolution imaging and force spectroscopy. This is despite the additional frequency shift noise due to the inherently low Q factor of the cantilever oscillating in a liquid. In this paper we present a tip based on an optical fiber which can operate in liquid with Q factors in excess of 100 using a 'diving bell' arrangement which allows only a small portion of the tip to be submerged. We demonstrate stable imaging and force spectroscopy using this set-up. The tips are based on scanning near-field optical microscopy tips and, when used with NC-AFM, provide a method of combining both high resolution mechanical and fluorescence studies of biomolecules and cells.

Determination of the local contact potential difference of PTCDA on NaCl: a comparison of techniques

There has been increasing focus on the use of Kelvin probe force microscopy (KPFM) for the determination of local electronic structure in recent years, especially in systems where other methods, such as scanning tunnelling microscopy/spectroscopy, may be intractable. We have examined three methods for determining the local apparent contact potential difference (CPD): frequency modulation KPFM (FM-KPFM), amplitude modulation KPFM (AM-KPFM), and frequency shift-bias spectroscopy, on a test system of 3,4,9,10-perylene tetracarboxylic dianhydride (PTCDA) on NaCl, an example of an organic semiconductor on a bulk insulating substrate. We will discuss the influence of the bias modulation on the apparent CPD measurement by FM-KPFM compared to the DC-bias spectroscopy method, and provide a comparison of AM-KPFM, AM-slope detection KPFM and FM-KPFM imaging resolution and accuracy. We will also discuss the distance dependence of the CPD as measured by FM-KPFM for both the PTCDA organic deposit and the NaCl substrate.

[Autopsy case of diffuse pleural thickening presenting respiratory impairment and benign asbestos pleurisy]

A 51-year-old man presented with back pain in 1997. He had a 30-year-history of occupational asbestos exposure. His chest CT showed bilateral pleural thickening and pleural effusion. The pleural effusion of the right thorax exhibited both elevated level of adenosine deaminase and increased numbers of lymphocytes. Antituberculous chemotherapy had no effect on the exudates. Progressive bilateral pleural thickening were found on chest CT, and pulmonary function tests showed severe restrictive ventilatory impairments since 1998. Thoracoscopic pleural biopsy was conducted in 2001 to exclude pleural malignant mesothelioma. No malignancy was found in pleural samples. After 3-year observation and excluding other causes, he was given a diagnosis of benign asbestos pleurisy. In 2005, fibrotic changes were found in both lower lung fields in chest CT. He suffered from respiratory failure with carbon dioxide retention, and died in 2006. The autopsy disclosed asbestos-related lung diseases. We suspected that diffuse pleural thickening could be a major cause of fatal respiratory impairment in this case.

Improved COBAS TaqMan hepatitis C virus test (Version 2.0) for use with the High Pure system: enhanced genotype inclusivity and performance characteristics in a multisite study

We have evaluated the COBAS TaqMan hepatitis C virus (HCV) test (version 2.0) for use with the High Pure system (HCVHPS V2), a new, revised real-time reverse transcription-PCR assay developed to improve the genotype quantitation of version 1.0 (HCVHPS V1). Revisions were made in the wash buffer and in the reverse transcription temperature. The genotype inclusivity of HCVHPS V2 was evaluated at three different sites, using HCVHPS V2, HCVHPS V1, and the COBAS AMPLICOR HCV MONITOR test (version 2.0) (CAHCM). The fully automated COBAS Ampliprep/COBAS TaqMan HCV test was also used in one of the participating laboratories. The mean differences in HCV RNA values between HCVHPS V2 and CAHCM and between HCVHPS V2 and HCVHPS V1 ranged from -0.21 to 0.13 log and from 0.24 to 1.27 log, respectively, with >0.5-log differences for genotypes 2, 3, 4, and 5. With a NIBSC panel of HCV genotypes 1 through 6, the measured HCVHPS V2 values were within 0.25 log of the nominal values for all 6 genotypes. When serial dilutions of genotype-specific clinical HCV specimens were tested, the assay showed a limit of detection between 10 and 20 IU/ml and a linear range of 25 IU/ml to 3.91 x 10(8) IU/ml. Clinical and analytical specificities of 100% were demonstrated with 100 HCV-seronegative specimens as well as with 12 non-HCV members of Flaviviridae and 22 additional microorganisms. These data indicate that HCVHPS V2 is a robust and accurate test for the quantitation of all six HCV genotypes and useful in monitoring viral load in all clinical HCV specimens.

Radiotherapy negates the effect of retroperitoneal nonclosure for prevention of lymphedema of the legs following pelvic lymphadenectomy for gynecological malignancies: an analysis from a questionnaire survey

Using patient questionnaires, we studied the long-term effect of leaving the peritoneum open on the incidence of lymphedema of the legs in patients following pelvic lymphadenectomy for gynecological malignancies. The patients were retrospectively assigned to one of two groups, depending on whether the retroperitoneum was closed or left open at surgery. Three years after surgery, we obtained valid questionnaire responses from 101 patients (43 cervical, 46 endometrial, and 12 ovarian cancers) in the closure group and 83 patients (34 cervical, 40 endometrial, and 9 ovarian cancers) in the nonclosure group. In patients' self-analysis, the overall incidence of lymphedema of the legs was significantly lower in the nonclosure group than in the closure group (25.3% and 50.5%, respectively; P < 0.01). The incidence of lymphedema of the legs was significantly increased by postoperative radiotherapy. Especially in the nonclosure group, the incidence of lymphedema was only 15.8% in patients who did not have radiotherapy, but it increased significantly (44.4%) (P < 0.05) when patients underwent radiotherapy. In conclusion, this questionnaire survey suggested that leaving the retroperitoneum open after lymphadenectomy is significantly effective in reducing the incidence of leg lymphedema, which impairs patients' quality of life more than expected by physicians.

Melanoma differentiation-associated gene-7 (mda-7)/interleukin (IL)-24 induces anticancer immunity in a syngeneic murine model

Previous studies have shown that the human melanoma differentiation-associated gene-7 (mda-7)/interleukin-24 (IL-24) has tumor-suppressor activity in vitro and in vivo. Additionally, in vitro studies using human peripheral blood mononuclear cells indicate that mda-7/IL-24 has TH1 cytokine-like activity. However, the individual properties of mda-7/IL-24 have been previously examined separately. Thus, there is not a single study that has examined both, antitumor and proimmune properties of mda-7/IL-24. Furthermore, the tumor suppressive activity and the cytokine activity of mda-7/IL-24 have not been previously tested in an immunocompetent setting. We therefore in the present study evaluated the antitumor and immune properties of mda-7/IL-24 in a murine syngeneic tumor model. In vitro, adenovirus-mediated mda-7 gene (Ad-mda7) transfer to murine fibrosarcoma (UV2237m; MCA16) and normal (10T1/2) cells significantly inhibited growth (P=0.001) and induced apoptosis in tumor cells but not in normal cells. In vivo, intratumoral administration of Ad-mda7 resulted in significant inhibition of tumor growth (P<0.05), with a subset of mice showing complete tumor regression. We next evaluated the immune potentiation activity of Ad-mda7 in a cancer vaccine model. UV2237m cells transfected with Ad-mda7 and injected into syngeneic immunocompetent C3H mice were unable to grow; however, they did grow in immunocompromised nude mice. These tumor-free C3H mice, when challenged with parental tumor cells experienced no tumor growth, suggesting induction of systemic immunity. Moreover, splenocytes prepared from vaccinated C3H mice demonstrated higher proliferative activity and produced elevated levels of TH1 cytokines compared with those from control mice. An in vitro subset analysis of splenocytes from vaccinated mice demonstrated a significant increase in the CD3(+)CD8(+) but not the CD3(+)CD4(+) cell population (P=0.019). Thus Ad-mda7 treatment of syngeneic tumors induces tumor cell death and promotes immune activation, leading to anticancer immunity.

Characterization of 17beta-hydroxysteroid dehydrogenase type 4 in human ovarian surface epithelial cells

The human ovarian surface epithelium (hOSE) is a single layer of mesothelial-type primitive epithelial cells that are potential estrogen targets. It has been reported that hOSE cells can produce estrogen. However, the mechanisms that regulate estrogen level(s) in hOSE cells are not yet known. To elucidate the enzymes involved in these reactions, we examined gene expression of 17beta-hydroxysteroid dehydrogenases (17beta-HSDs) in primary hOSE (POSE) and OSE2a cells using RT-PCR. We found that POSE cells and cells of the immortalized hOSE line, OSE2a, bidirectionally converted estrone (E1) and 17beta-estradiol (E2). Both cell types expressed mRNA for 17beta-HSD type 1 (17beta-HSD1), suggesting that the enzyme is involved in the E1 to E2 conversion. Interestingly, both cells expressed 17beta-HSD4 mRNA but not 17beta-HSD2 mRNA. We prepared an antibody against the carboxyl terminal of 17beta-HSD4 (anti-17beta-HSD4 antibody), which recognized the 80 and 48 kDa proteins in POSE and OSE2a cells based on immunoblot analysis. Furthermore, immunohistochemical study revealed the presence of 17beta-HSD4 in hOSE cells in the human ovary. These results suggest that 17beta-HSD4 is involved in estrogen inactivation and may protect against an excessive accumulation of E2 in hOSE cells.

Transient increase in squamous cell carcinoma antigen expression in cultured cervical carcinoma CaSki cells in response to exposure to cis-diamminedichloroplatinum

The present study was conducted to elucidate the molecular mechanism underlying the transient increase in circulating squamous cell carcinoma antigen (SCC Ag) levels in response to CIS-diamminedichloroplatinum (CDDP) infusion using an in vitro model. The uterine cervical squamous carcinoma CaSki cells were cultured for 72 h after 3 h exposure to 5.0 microg/ml CDDP. The effects of CDDP exposure on the proliferative activity and apoptosis in cultured CaSki cells were determined by bromodeoxyuridine (BrdU) uptake and cell counting and by the TUNEL assay, respectively. SCC Ag levels in cultured CaSki cells and culture media were determined with the use of SCC-RIA kit. The expression of SCC Ag-1 mRNA and SCC Ag-2 mRNA in cultured CaSki cells was assessed using semiquantitative RT-PCR with Southern blot analysis. The number of BrdU-positive CaSki cells significantly decreased 6 h after exposure to CDDP, whereas the apoptosis-positive rate of cultured CaSki cells significantly increased 12 h after the CDDP exposure. The number of cultured CaSki cells significantly decreased 72 h after the CDDP exposure. The total SCC Ag protein levels in both cultured CaSki cells and the culture media after the 3-hour CDDP exposure increased in a time-dependent manner during the subsequent incubation for 48 h. Semiquantitative RT-PCR revealed that the expression levels of both SCC Ag-1 and SCC Ag-2 mRNA increased (1.7- and 2.7-fold, respectively) 12 h after the exposure to CDDP relative to those before the subsequent cultures. Exposure of uterine cervical squamous carcinoma CaSki cells to CDDP resulted in a transient increase in SCC Ag protein and mRNA expression in those cells during the initial 12 h after the exposure, being associated with decreased proliferative activity and increased apoptosis of those cells.

Effect of cis-diammine dichloroplatinum on vascular endothelial growth factor expression in uterine cervical carcinoma

PURPOSE OF INVESTIGATION

In this study, we investigated the effects of cis-diammine dichloroplatinum (CDDP) on VEGF mRNA expression and VEGF production in uterine cervical carcinoma tissues obtained from patients with locally advanced disease and in CaSki cells cultured in vitro.

METHODS

VEGF in cultured CaSki cells and in the culture media was measured using a sensitive enzyme-linked immunosorbent assay (ELISA) before and 24 h, 48 h and 72 h after 3 h exposure to CDDP. VEGF mRNA expression in CaSki cells was assessed by the semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) before and 24 h and 48 h after 3 h exposure to CDDP. We also examined the effect of CDDP on microvessel counts in uterine cervical carcinoma tissues obtained before and after high-dose CDDP intraarterial chemotherapy. Immunohistochemical staining using a monoclonal antibody against CD34 was carried out with cervical carcinoma tissue specimens, and microvessel counts were quantified by counting vessels.

RESULTS

CDDP treatment resulted in significant increases in not only VEGF concentrations in cultured CaSki cells and culture media but also in VEGF mRNA expression levels in cultured CaSki cells in a time-dependent and dose-dependent manner compared to untreated controls (p < 0.05, n = 5). On the other hand, VEGF concentrations and microvessel counts in cervical carcinoma tissues were significantly lower in cases with complete response (CR) and partial response (PR), compared to those before treatment (p < 0.05, n = 5 ). By contrast, in cases with no change (NC) to CDDP, both VEGF concentrations and microvessel counts did not decrease and rather showed a somewhat increase compared with levels prior to the treatment.

CONCLUSIONS

These results suggest that CDDP-induced increases in VEGF production by cervical carcinoma cells may stimulate angiogenesis in the tumor lesion after CDDP treatment.

Influence of hemodialysis on echocardiographic Doppler indices of the left ventricle: changes in parameters of systolic and diastolic function and Tei index

AIMS

Numbers of previous studies have evaluated the influence of dialysis-induced altered loading condition on Doppler-echocardiographic indices of left ventricle in patients with chronic renal failure. It has been suggested that most of Doppler-derived indices are preload-dependent. On the other hand, there are no studies that have evaluated the influence of hemodialysis on Tei index; a new Doppler-derived index obtained by isovolumetric contraction time plus isovolumetric relaxation time divided by ejection time. The aim of this study is to evaluate whether Tei index is also influenced by dialysis-induced altered loading condition as well as other Doppler-derived indices, and to assess the possibility that Tei index is also preload-dependent.

PATIENTS AND METHODS

Thirty-two patients with chronic renal failure (21 men and 11 women, aged 48-93 years) on maintenance hemodialysis were evaluated for Doppler-derived indices before and after hemodialysis. We studied parameters of diastolic function (peak velocities of mitral inflow in early diastole (E) and late diastole from atrial filling (A), ratio of A to E (A/E), deceleration time (DT), and isovolumetric relaxation time (IRT)), parameters of systolic function (ejection time (ET), pre-ejection period (PEP), ratio of PEP to ET (PEP/ET), and isovolumetric contraction time (ICT)) and Tei index.

RESULTS

Hemodialysis resulted in significant decreases in E, increase in A/E, prolongation of IRT, no change in A and DT; significant prolongation of ICT and PEP, shortening of ET, and increase in PEP/ET and a significant increase in Tei index (0.42 +/- 0.16 vs 0.51 +/- 0.16, p < 0.0001). When patients were subdivided into 2 groups based on weight loss after hemodialysis (> or = 1.5 kg and < 1.5 kg), only the group that lost > or = 1.5 kg had significant change in Tei index before and after hemodialysis (0.40 +/- 0.15 vs 0.52 +/- 0.17, p = 0.0002).

CONCLUSION

This study demonstrates that not only most of Doppler-derived indices but also Tei index is affected by dialysis-induced altered loading condition and suggests that Tei index is possibly preload-dependent.

Role of SEREX-defined immunogenic wild-type cellular molecules in the development of tumor-specific immunity

Recognition of altered self-antigens in tumor cells by lymphocytes forms the basis for antitumor immune responses. The effector cells in most experimental tumor systems are CD8(+) T cells that recognize MHC class I binding peptides derived from molecules with altered expression in tumor cells. Although the need for CD4(+) helper T cells in regulating CD8(+) T cells has been documented, their target epitopes and functional impact in antitumor responses remain unclear. We examined whether broadly expressed wild-type molecules in murine tumor cells eliciting humoral immunity contributed to the generation of CD8(+) T cells and protective antitumor immune responses to unrelated tumor-specific antigens [mutated ERK2 (mERK2) and c-erbB2/HER/neu (HER2)]. The immunogenic wild-type molecules, presumably dependent on recognition by CD4(+) helper T cells, were defined by serological analysis of recombinant cDNA expression libraries (SEREX) using tumor-derived lambda phage libraries screened with IgG antibodies of hosts bearing transplanted 3-methylchoranthrene-induced tumors. Coimmunization of mice with plasmids encoding SEREX-defined murine wild-type molecules and mERK2 or HER2 led to a profound increase in CD8(+) T cells specific for mERK2 or HER2 peptides. This heightened response depended on CD4(+) T cells and copresentation of SEREX-defined molecules and CD8(+) T cell epitopes. In tumor protection assays, immunization with SEREX-defined wild-type molecules and mERK2 resulted in an inhibition of pulmonary metastasis, which was not achieved by immunization with mERK2 alone.

Limitations of successive transradial approach in the same arm: the Japanese experience

The transradial approach (TRA) has been used for diagnostic and interventional cardiology. It has not previously been determined how many times the same radial artery can be cannulated without complications. A total of 812 patients (502 men and 310 women) underwent angiography or angioplasty via the TRA between 1997 and 1999 at our institution with a total of 1,438 procedures. Sheaths were 5 (55%) or 6 Fr (45%). Dropout rates of 3.5% and 7.9% were found at the second TRA attempt in the men and the women, respectively. Of the 62 TRA failures, 56 (90%) were due to narrowing or occlusion of the radial artery after the previous TRA procedure. A third TRA procedure was possible in 90% of the men and 80% of the women. A fifth TRA procedure was possible in 70% of the men and 50% of the women. The dropout rates for TRA increased as successive punctures were performed. This was primarily due to vessel narrowing and occlusion occurring as a function of multiple punctures.

Left ventricular mass and global function in essential hypertension after antihypertensive therapy

This study compares left ventricular global function in 55 patients (25 with hypertrophy and 30 without hypertrophy) with essential hypertension, whose blood pressure had been stable for longer than 1 year, with that in 35 healthy subjects. Left ventricular global function was calculated using the echocardiographic Doppler index as described by Tei et al. (Tei index). No significant differences were observed in echocardiographic left ventricular systolic function between the three groups. Left ventricular global function differed significantly between the three groups, however, suggesting impaired left ventricular global function even in the absence of left ventricular hypertrophy. Similar changes were observed in the ratio of peak velocity of atrial systole to peak velocity of early diastole during left ventricular inflow waveform (A/E), indicating that this disorder mainly reflects impaired left ventricular diastolic function. Unlike A/E, the Tei index is not affected by increasing age, and, therefore, is appropriate for evaluating left ventricular global function in hypertensive patients, most of whom are middle-aged or older. This index may be useful for determining treatment strategy and evaluating treatment effects.

Effect of prenatal melatonin exposure on gonadotropins and prolactin secretion in male and female rat pups

We evaluated whether melatonin administration to pregnant rats during the final week of pregnancy affects prepubertal secretion of luteinizing hormone (LH), follicle stimulating hormone (FSH), and prolactin in offspring. Melatonin was administered in the drinking water from day 14 to delivery. LH, FSH and prolactin concentrations were determined in plasma sampled from offspring between 5 and 30 days in the dark portion of the diurnal cycle. Administration of 2 or 20 microg/ml melatonin did not affect LH or FSH in male or female offspring. The 20-microg/ml dose caused a significant increase in prolactin in males and females at day 15. In contrast, melatonin, 2 or 20 microg/ml, decreased prolactin at days 25 and 30 in females and day 25 in males. Thus, prenatal melatonin exposure alters prolactin secretion, but not that of LH and FSH in infantile and prepubertal male and female rats.

Echocardiographic evaluation of right cardiac function in patients with chronic pulmonary diseases

It is clinically important to evaluate the severity of right ventricular (RV) overload in patients with chronic pulmonary diseases (CPD). For such evaluation, echocardiography has been widely used because the procedure is noninvasive and can be performed repeatedly. We evaluated the severity of RV overload in CPD patients to assess the usefulness of pulsed Doppler echocardiography. The A/E ratio and deceleration time of early RV inflow velocity correlated significantly with the mean pulmonary artery pressure (MPAP) both in patients with and without CPD. The acceleration time/RV ejection time (AcT/RVET) was significantly lower in CPD patients than control subjects and correlated significantly with MPAP. Furthermore, AcT/RVET improved in patients with mild respiratory failure after oxygen therapy, along with a decrease in MPAP. We also compared the new index of myocardial performance (NI) in control subjects and patients with pulmonary tuberculosis sequelae (TB) undergoing home oxygen therapy. The NI was significantly higher in the TB group. Although these results were satisfactory, the pulsed Doppler echocardiography has certain disadvantages because monitoring is influenced by anatomical factors and it is difficult to perform in patients with atrial fibrillation or tachycardia. We conclude that echocardiography using a Doppler method is a useful noninvasive technique for assessment of the right heart system. The precision of this procedure can be improved by combination with other echocardiographic indices of RV overload.