Asymptomatic esophageal perforation discovered after elective cardiac surgery: the importance of clinical awareness

Transesophageal echocardiography (TEE) has become an indispensable part of cardiothoracic surgery at present and is considered to be a safe procedure, rarely associated with complications. However, TEE may cause serious and life threatening complications, as presented in this case report. We describe a patient who developed an empyema after elective cardiac surgery due to an esophageal perforation caused by TEE, without any clinical symptoms. Risk factors for TEE-related complications, identified in recent literature, will be discussed as well as the remarkable absence of clinical symptoms in this particular patient.

Adaptive Nutrition Intervention Stabilizes Serum Phosphorus Levels in Hemodialysis Patients: A Multicenter Decentralized Clinical Trial Using Real-World Data

OBJECTIVE

This study aims to evaluate the effect of an adaptive nutritional and educational intervention for patients on hemodialysis (HD) in a routine care setting, using real-world data from electronic health records.

METHODS

Decentralized clinical trial of seven HD facilities recruited patients who have been on HD for over 3 months (N = 153) for an 8-week adaptive intervention protocol. Patients were divided into four groups: (1) control (2) education intervention (3) meal intervention (4) education and meal interventions. Educational contents were digitally delivered via mobile phones and premade meals tailored on laboratory findings were home-delivered. Changes in serum electrolytes and malnutrition inflammation score (MIS) were analyzed.

RESULTS

Meal intervention statistically significantly stabilized serum phosphorus level (β = -0.81 mg/dL, 95% confidence interval = [-1.40, -0.22]) at week 8, with increased likelihood of being within target serum value range (odds ratio = 1.21, 95% confidence interval = [1.04, 1.40]). Meal group showed better nutritional status (MIS = 3.65) than the education group (MIS = 5.10) at week 8 (adjusted p < .05). No significant changes were observed in serum potassium level, depression, and self-efficacy.

CONCLUSION

It was demonstrated that an adaptive meal intervention in a real-world care setting may benefit serum phosphorus control and nutritional status of patients on HD, without negative effect on depression levels or self-efficacy. More work is needed to develop an effective educational intervention.

Identification of distinct subgroups in moderately severe rheumatic mitral stenosis using data-driven phenotyping of longitudinal hemodynamic progression

Background

Rheumatic mitral stenosis (MS) is a significant cause of valvular heart disease. Pulmonary artery systolic pressure (PASP) reflects the hemodynamic consequences of MS and is used to determine treatment strategies. However, PASP progression and expected outcomes in patients with moderately severe MS remain unclear.

Purpose

We aimed to examine the impact of progression rate of PASP in moderately severe MS.

Methods

A cohort of 866 consecutive patients with moderately severe rheumatic MS (1.0 cm2.

Results

Data-driven phenotyping identified two distinct trajectories based on PASP progression: a rapid progression group (N=38, 8.7%) and a slow progression group (N=398, 91.3%). Patients in the rapid progression group were older and had more comorbidities than patients in the slow progression group, including diabetes, and atrial fibrillation (all P&lt;0.05). The initial mean diastolic pressure gradient and PASP were higher in the rapid progression group than in the slow progression group (6.2±2.4 mmHg vs. 5.1±2.0 mmHg, P=0.001, and 42.3±13.3 mmHg vs. 33.0±9.2 mmHg, P&lt;0.001, respectively). During a mean follow-up of 7.0±3.0 years, the event-free survival rate was significantly lower in the rapid progression group than in the slow progression group (log-rank P&lt;0.001). Rapid PASP progression was a significant risk factor for composite outcomes even after adjusting for comorbidities (hazard ratio: 3.08, 95% confidence interval (CI): 1.68–5.64, P&lt;0.001). Multivariate regression analysis revealed that PASP&gt;40 mmHg was independently associated with the probability of rapid progression group allocation (odds ratio: 4.95, 95% CI: 2.08–11.99, P&lt;0.001).

Conclusions

Two groups with distinct patterns of PASP progression were identified. Rapid PASP progression was associated with a significantly higher risk of the composite outcomes. The main independent echocardiographic predictor for rapid progression group allocation was initial PASP&gt;40 mmHg.

Funding Acknowledgement

Type of funding sources: Private hospital(s). Main funding source(s): This study was supported by a Severance Hospital Research fund for Clinical excellence (SHRC) (C-2020-0041) and a faculty research grant of Yonsei University College of Medicine (6-2020-0156).

Characterizing Determinants of Near-Road Ambient Air Quality for an Urban Intersection and a Freeway Site

INTRODUCTION

Near-road ambient air pollution concentrations that are affected by vehicle emissions are typically characterized by substantial spatial variability with respect to distance from the roadway and temporal variability based on the time of day, day of week, and season. The goal of this work is to identify variables that explain either temporal or spatial variability based on case studies for a freeway site and an urban intersection site. The key hypothesis is that dispersion modeling of near-road pollutant concentrations could be improved by adding estimates or indices for site-specific explanatory variables, particularly related to traffic. Based on case studies for a freeway site and an urban intersection site, the specific aims of this project are to (1) develop and test regression models that explain variability in traffic-related air pollutant (TRAP) ambient concentration at two near-roadway locations; (2) develop and test refined proxies for land use, traffic, emissions and dispersion; and (3) prioritize inputs according to their ability to explain variability in ambient concentrations to help focus efforts for future data collection and model development.

The key pollutants that are the key focus of this work include nitrogen oxides (NOx), carbon monoxide (CO), black carbon (BC), fine particulate matter (PM2.5; PM ≤ 2.5 μm in aerodynamic diameter), ultrafine particles (UFPs; PM ≤ 0.1 μm in aerodynamic diameter), and ozone (O3). NOx, CO, and BC are tracers of vehicle emissions and dispersion. PM2.5 is influenced by vehicle table emissions and regional sources. UFPs are sensitive to primary vehicle emissions. Secondary particles can form near roadways and on regional scales, influencing both PM2.5 and UFP concentrations. O3 concentrations are influenced by interaction with NOx near the roadway. Nitrogen dioxide (NO2), CO, PM2.5, and O3 are regulated under the National Ambient Air Quality Standards (NAAQS) because of demonstrated health effects. BC and UFPs are of concern for their potential health effects. Therefore, these pollutants are the focus of this work.

METHODS

The methodological approach includes case studies for which variables are identified and assesses their ability to explain either temporal or spatial variability in pollutant ambient concentrations. The case studies include one freeway location and one urban intersection. The case studies address (1) temporal variability at a fixed monitor 10 meters from a freeway; (2) downwind concentrations perpendicular to the same location; (3) variability in 24-hour average pollutant concentrations at five sites near an urban intersection; and (4) spatiotemporal variability along a walking path near that same intersection.

The study boundary encompasses key factors in the continuum from vehicle emissions to near-road exposure concentrations. These factors include land use, transportation infrastructure and traffic control, vehicle mix, vehicle (traffic) flow, on-road emissions, meteorology, transport and evolution (transformation) of primary emissions, and production of secondary pollutants, and their resulting impact on measured concentrations in the near-road environment. We conducted field measurements of land use, traffic, vehicle emissions, and near-road ambient concentrations in the vicinity of two newly installed fixed-site monitors. One is a monitoring station jointly operated by the U.S. Environmental Protection Agency (U.S. EPA) and the North Carolina Department of Environmental Quality (NC DEQ) on I-40 between Airport Boulevard and I-540 in Wake County, North Carolina. The other is a fixed-site monitor for measuring PM2.5 at the North Carolina Central University (NCCU) campus on E. Lawson Street in Durham, North Carolina. We refer to these two locations as the freeway site and the urban site, respectively. We developed statistical models for the freeway and urban sites.

RESULTS

We quantified land use metrics at each site, such as distances to the nearest bus stop. For the freeway site, we quantified lane-by-lane total vehicle count, heavy vehicle (HV) count, and several vehicle-activity indices that account for distance from each lane to the roadside monitor. For the urban site, we quantified vehicle counts for all 12 turning movements through the intersection. At each site, we measured microscale vehicle tailpipe emissions using a portable emission measurement system.

At the freeway site, we measured the spatial gradient of NOx, BC, UFPs, and PM, quantified particle size distributions at selected distances from the roadway and assessed partitioning of particles as a function of evolving volatility. We also quantified fleet-average emission factors for several pollutants.

At the urban site, we measured daily average concentrations of nitric oxide (NO), NOx, O3, and PM2.5 at five sites surrounding the intersection of interest; we also measured high resolution (1-second to 10-second averages) concentrations of O3, PM2.5, and UFPs along a pedestrian transect. At both sites, the Research LINE-source (R-LINE) dispersion model was applied to predict concentration gradients based on the physical dispersion of pollution.

Statistical models were developed for each site for selected pollutants. With variables for local wind direction, heavy-vehicle index, temperature, and day type, the multiple coefficient of determination (R2) was 0.61 for hourly NOx concentrations at the freeway site. An interaction effect of the dispersion model and a real-time traffic index contributed only 24% of the response variance for NOx at the freeway site. Local wind direction, measured near the road, was typically more important than wind direction measured some distance away, and vehicle-activity metrics directly related to actual real-time traffic were important. At the urban site, variability in pollutant concentrations measured for a pedestrian walk-along route was explained primarily by real-time traffic metrics, meteorology, time of day, season, and real-world vehicle tailpipe emissions, depending on the pollutant. The regression models explained most of the variance in measured concentrations for BC, PM, UFPs, NO, and NOx at the freeway site and for UFPs and O3 at the urban site pedestrian transect.

CONCLUSIONS

Among the set of candidate explanatory variables, typically only a few were needed to explain most of the variability in observed ambient concentrations. At the freeway site, the concentration gradients perpendicular to the road were influenced by dilution, season, time of day, and whether the pollutant underwent chemical or physical transformations. The explanatory variables that were useful in explaining temporal variability in measured ambient concentrations, as well as spatial variability at the urban site, were typically localized real-time traffic-volume indices and local wind direction. However, the specific set of useful explanatory variables was site, context (e.g., next to road, quadrants around an intersection, pedestrian transects), and pollutant specific. Among the most novel of the indicators, variability in real-time measured tailpipe exhaust emissions was found to help explain variability in pedestrian transect UFP concentrations. UFP particle counts were very sensitive to real-time traffic indicators at both the freeway and urban sites. Localized site-specific data on traffic and meteorology contributed to explaining variability in ambient concentrations. HV traffic influenced near-road air quality at the freeway site more so than at the urban site. The statistical models typically explained most of the observed variability but were relatively simple. The results here are site-specific and not generalizable, but they are illustrative that near-road air quality can be highly sensitive to localized real-time indicators of traffic and meteorology.

The white coat public art project: using the white coat as a canvas for reflection for women in medicine

OBJECTIVES

Burnout and low job satisfaction have disproportionately impacted female physicians compared with their male counterparts, with gender-specific oppression and bias in the workforce. This project aims to address the relationship of women in medicine to their chosen field through public art.

STUDY DESIGN

A call for using the white coat as a canvas to describe positive attributes and self-reflection was shared with all American Medical Women's Association (AMWA) branches at medical schools.

METHODS

Students in AMWA branches created white coats, designing them to answer the posed question.

RESULTS

White coats were sent to the national conference for display, revealing certain themes, challenges, resilience, and humanization of the training and working experience for women in medicine.

CONCLUSION

This white coat public art project directly and indirectly addresses causes of burnout and serves as a way to create community, address isolation, and empower women in medicine.

Trends in the total numbers of HBV and HCV carriers in Japan from 2000 to 2011

We estimated the total number of undiagnosed HBV and HCV carriers and patients with hepatitis virus-related disease in Japan according to 6 different groups classified by their natural histories during 2011. In 2011, the total number of carriers and patients infected with HBV or HCV was estimated according to 6 groups using government reports and reports from the hepatitis epidemiology research group of The Ministry of Health, Labor and Welfare in Japan. In 2011, the total number of hepatitis virus carriers was estimated to be 2 090 128-2 840 128 in which the estimated number of undiagnosed HCV and HBV carriers was 776 826 (HBV: 481 470; HCV: 295 356). The total number of treated patients, as either inpatients or outpatients, was estimated to be 811588 (HBV: 303 366; HCV: 520 600) in 2011. It is presumed that many carriers shirk consultation for many reasons, such as patients' misunderstanding, lack of awareness and forgetfulness of their positive status. The numbers of infected patients who did not seek treatment increased gradually to 501 714-1 251 714 (HBV: 333 791-483 791; HCV: 167 923-767 923) in 2011. Compared to 2000, the number of undiagnosed carriers was significantly reduced in 2011 probably because of the well-organized, effective national hepatitis virus screening system that has been launched by the Japanese government since 2002. Moreover, the increase in the number of untreated persons who are aware of their positive status shows that more effort should be invested in improving the referral system from screening centres to core hospitals.

Glutamate Receptor Interacting Protein 1 Regulates CD4(+) CTLA-4 Expression and Transplant Rejection

PDZ domains are common 80- to 90-amino-acid regions named after the first three proteins discovered to share these domains: postsynaptic density 95, discs large, and zonula occludens. PDZ domain-containing proteins typically interact with the C-terminus of membrane receptors. Glutamate receptor interacting protein 1 (GRIP1), a seven-PDZ domain protein scaffold, regulates glutamate receptor surface expression and trafficking in neurons. We have found that human and mouse T cells also express GRIP1. T cell-specific GRIP1(-/-) mice >11 weeks old had prolonged cardiac allograft survival. Compared with wild-type T cells, in vitro stimulated GRIP1(-/-) T cells had decreased expression of activation markers and increased apoptotic surface marker expression. Surface expression of the strong T cell inhibitory molecule cytotoxic T lymphocyte antigen-4 (CTLA-4) was increased on GRIP1(-/-) T cells from mice >11 weeks old. CTLA-4 increases with T cell stimulation and its surface expression on GRIP1(-/-) T cells remained high after stimulation was removed, indicating a possible internalization defect in GRIP1-deficient T cells. CTLA-4-blocking antibody treatment following heart transplantation led to complete rejection in T cell GRIP1(-/-) mice, indicating that increased CTLA-4 surface expression contributed to the extended graft survival. Our data indicate that GRIP1 regulates T cell activation by regulating CTLA-4 surface expression.

The localization and orientation of specific genes in the chloroplast chromosome of Vicia faba

The genes for six chloroplast polypeptides have been localized on the map of Vicia faba chloroplast DNA using heterologous probes. These include the three subunits (α, β, ε) of CF1 of ATP synthase, subunit III of CF0 from ATP synthase, the 32 kilodalton thylakoidal membrane protein of photosystem II and cytochrome f of the electron transport chain. The direction of transcription has been determined for the three subunits of CF1 and the 32 kilodalton thylakoidal protein. The physical map of the chloroplast DNA has also been expanded to include Sma1 sites in addition to previously mapped restriction enzyme sites. Finally, the genetic arrangement of Vicia faba chloroplast DNA was compared to other known genetic maps.

Long-term results of Tokyo Children's Cancer Study Group trials for childhood acute lymphoblastic leukemia, 1984-1999

We report the long-term results of Tokyo Children's Cancer Study Group's studies L84-11, L89-12, L92-13, and L95-14 for 1846 children with acute lymphoblastic leukemia, which were conducted between 1984 and 1999. The value of event-free survival (EFS)+/-s.e. was 67.2+/-2.2% at 10 years in L84-11, which was not improved in the following two studies, and eventually improved to 75.0+/-1.8% at 10 years in L95-14 study. The lower EFS of the L89-12 reflected a high rate of induction failure because of infection and delayed remission in very high-risk patients. The L92-13 study was characterized by short maintenance therapy; it resulted in poor EFS, particularly in the standard-risk (SR) group and boys. Females did significantly better than males in EFS in the early three studies. The gender difference was not significant in overall survival, partly because >60% of the males survived after the testicular relapse. Randomized studies in the former three protocols revealed that intermediate- or high-dose methotrexate therapy significantly reduced the testicular relapse rate. In the L95-14 study, gender difference disappeared in EFS. Contrary to the results of larger-scale studies, the randomized control study in the L95-14 reconfirmed with updated data that dexamethasone 8 mg/m(2) had no advantage over prednisolone 60 mg/m(2) in the SR and intermediate-risk groups. Prophylactic cranial irradiation was assigned to 100, 80, 44, and 44% of the patients in the studies, respectively. Isolated central nervous system relapse rates decreased to <2% in the last two trials. Secondary brain tumors developed in 12 patients at 8-22 years after cranial irradiation. Improvement of the remission induction rates and the complete omission of irradiation are currently main objectives in our studies.

Prognostic Factors for Locoregional Recurrence in Operable Breast Cancer Patients Treated with Preoperative Systemic Chemotherapy

Background: We aimed to evaluate the clinicopathologic factors affecting locoregional recurrence (LRR) in potentially operable breast cancer patients receiving preoperative systemic chemotherapy (PST).Methods: We reviewed the records of 316 breast cancer patients treated with PST (doxorubicin/cyclophosphamide, 101; docetaxel /capecitabine, 103; paclitaxel/gemcitabine, 43; doxorubicin/docetaxel, 69) followed by surgery and adjuvant radiotherapy between 2002 and 2006. The majority of patients had clinical positive axillary lymph nodes. To define the prognostic factors for LRR, age, clinical stage, hormone receptor (HR) and HER2 status, clinical and pathologic response, type of operation, pathological characteristics including tumor size, tumor grade, nodal status, number of positive axillary nodes, size of metastatic lymph node and status of resection margin and tumor multiplicity before and after PST were analyzed.Results: Overall 52 patients (16.5%) in the primary tumor and 87 patients (27.5%) in the axillary nodes achieved a pathologic complete response (pCR), and 206 patients (65.2%) underwent breast conserving surgery (BCS). With a median follow-up of 52.4 month (range: 4.7 - 89.4), total 18 (5.7%) patients developed LRR; 2 of 110 (1.8%) patients with mastectomy vs. 16 of 206 (7.7%) patients with BCS (p=0.04). Other significant factors in the univariate analysis were clinical T stage, HR status, clinical response and tumor multiplicity. A pCR in the primary tumor or node was not a prognostic factor for LRR in this study. In multivariate analysis, clinical T stage (T3/4, HR 7.8; 95% CI, 2.33-26.24; P=0.001), hormone receptor status (negative, HR 6.2; 95% CI, 1.91-20.22; P=0.002) and type of surgery (BCS, HR 9.5; 95% CI, 1.97-46.37; P=0.005) were independent prognostic factors. Among patients with BCS, advanced clinical T stage (HR 12.4; 95% CI, 3.45-44.56; P&lt;0.001), negative hormone receptor (HR 4.74; 95% CI, 1.33-16.96; P=0.02), non-responding disease (HR 6.54; 95% CI, 1.07-40.12; P=0.04) and multiple tumors (HR 4.36; 95% CI, 1.06-17.90; P=0.04) developed more frequent LRR.Conclusions: Significantly more patients with advanced clinical T stage, negative HR status and BCS developed LRR in operable breast cancer treated with PST. Moreover, in patients with BCS after PST, clinically non-responding disease and multiple tumors showed unfavorable prognosis besides the larger tumors and negative hormone receptor.Partly supported by NCC Grant No 0610240

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1095.

Prognosis of Metaplastic Breast Cancer: Poorer Than the Rest of Triple-Negative Breast Cancer

Background: The biologic behavior of metaplastic breast cancer (MBC) has not been well elucidated due to its rarity and heterogeneity. This study was designed to assess the clinical and tumor characteristics and outcomes of MBC patients as compared with invasive ductal carcinoma (IDC) in general and the triple-negative (TN) subtype.Materials and methods: This study included 35 MBC and 2,839 IDC patients diagnosed at the National Cancer Center, Korea between 2000 and 2008. We, retrospectively, reviewed the clinicopathologic characteristics and clinical outcomes.Results: The mean age was 47.4 years for MBC group and 48.3 years for IDC group. The MBC group presented with larger tumors (≥ T2, 78.8% vs 41.0%; P&lt;0.001), higher histologic grade (grade 3, 92.0% vs 44.6%; P&lt;0.001), fewer ER and PgR positivity (ER+, 14.3% vs 69.0% ; P&lt;0.001 and PgR+, 25.7% vs 66.1%; P&lt;0.001), higher Ki-67 expression (35.5%±26.2% vs 20.6% ±19.8%; P=0.024) and more TN subtypes (48.6% vs 11.9%; P&lt;0.001) than IDC group. Excluding de novo stage IV patients, 14 of 32 (43.7%) MBC patients and 260 of 2782 (9.4%) IDC patents developed disease recurrence with a median follow-up of 36.2 months (range, 4.9-117.8 months). MBC was a poor prognostic factor for disease recurrence in univariate and multivariate analysis (HR 5.19; 95% CI, 2.04-13.18; P=0.001). MBC patients demonstrated aggressive pathologic features and experienced more disease recurrence (HR 4.77; 95% CI, 1.99-11.44; P=0.001) even when compared with 330 patients with TN subtype.Conclusions:Patients with metaplastic breast carcinoma appeared to have inherent aggressive tumor biology with poorer clinical outcomes than those with IDC in general and TN subtype.Partly supported by NCC Grant No 0610240

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4057.

Correlation of tumor size on preoperative breast MRI and pathologic tumor size in Asian patients

e11546

Background: As many Asian patients want breast conserving therapy (BCT), use of magnetic resonance imaging (MRI) increase in preoperative diagnosis for breast cancer. But the impact of MRI on these patients has not been unclear. Methods: From January 2008 to July 2008, 423 patients underwent breast cancer surgery in National Cancer Center, Korea. We enrolled 357 patients consecutively in this retrospective study; 290 patients (non-MRI group) with preoperative mammography (MMG) and ultrasonography (US) vs. 66 patients (MRI group) with additional MRI to MMG, US and excluded 67 patients (42 patients with preoperative chemotherapy, 8 patients with ipsilateral recurrence, 17 patients whose MRI showed no residual lesion after excisional biopsy). We examined MRI effect on mastectomy rate, intraoperative conversion from BCT to mastectomy, positive margin rate in frozen specimen in both group. In MRI group, we evaluated the correlation between tumor size on US, MRI and pathologic tumor size. Results: Mean age of this study was 48.89 years (Non-MRI group: 50.70 years vs. MRI group: 46.33 years, p=0.001). The rate of mastectomy wasn’t different in both groups (Non-MRI group: 13.7% vs. MRI group: 19.4%, p=0.252). Intraoperative conversion to mastectomy was performed frequently in MRI group. (Non-MRI group: 1.7% vs. MRI group: 7.5%, p=0.023). But positive margin rate in frozen specimen was similar in both groups (Non-MRI group: 23.2% vs. MRI group: 34.0%, p=0.111). In MRI group, mean tumor size on MRI, US was 3.07cm, 1.98cm respectively. Mean pathologic tumor size was 2.67cm. The tumor size on MRI correlated strongly with the pathologic tumor size. The correlation coefficient was 0.732 (p=0.0001). But the tumor size on US didn’t correlate with the pathologic tumor size (p=0.066). In twenty nine patients whose MMG showed suspicious microcalcification, tumor size on MRI also correlated strongly with pathologic tumor size. The correlation coefficient was 0.693 (p=0.0001). But US didn’t show the correlation with the pathologic tumor size in these patients. Conclusions: Preoperative breast MRI didn’t give the impact on breast cancer surgery in Asian patients and could overestimate the size of tumor. But it could strongly correlate with the pathologic tumor size in Asian patients.

No significant financial relationships to disclose.

RBF multiuser detector with channel estimation capability in a synchronous MC-CDMA system

The authors propose a multiuser detector with channel estimation capability using a radial basis function (RBF) network in a synchronous multicarrier-code division multiple access (MC-CDMA) system. The authors propose to connect an RBF network to the frequency domain to effectively utilize the frequency diversity. Simulations were performed over frequency-selective and multi-path fading channels. These simulations confirmed that the proposed receiver can be used both for the channel estimation and as a multi-user receiver, thus permitting an increase in the number of active users.

Fundamental study of small interfering RNAs for ganglioside GD3 synthase gene as a therapeutic target of lung cancers

Gangliosides GD3 and GD2 are specifically expressed in neuro-ectoderm-derived tumors, and are considered to play roles in the malignant properties of those cells. We analysed effects of small interfering (si) RNAs against GD3 synthase gene on the expression of ganglioside GD2 and biological phenotypes of human lung cancer cells expressing GD2. An siRNA could suppress the mRNA level of GD3 synthase gene even by single transfection, whereas repeated transfection was required to suppress GD2 expression on the cell surface. Significant reduction in the cell growth and invasion activity was observed in both lung cancer cell lines examined, when repeatedly transfected with the siRNA twice a week. DNA ladder formation was observed after third transfection, indicating the potent induction of apoptosis. Stable transfection of an RNAi expression vector with H1 RNA promoter was also examined. Transfectant cells with the RNAi expression vector showed almost equivalent suppression of GD2 expression and tumor properties in vitro. Furthermore, the stable transfectant cells showed slower cell growth than the control cells in severe combined immunodeficiency mice. These results suggested that siRNAs and/or RNAi expression vectors to generate siRNAs are promising approach to overcome human lung cancers.

Value of repeat ultrasound-guided fine-needle aspiration in nodules with benign cytological diagnosis

PURPOSE

To assess the value of repeat ultrasound-guided fine-needle aspiration (US-FNA) in nodules with benign cytological diagnosis.

MATERIAL AND METHODS

One-hundred-and-eighty-seven patients undergoing repeat US-FNA were included after a benign cytological diagnosis had been made by the initial US-FNA. They were divided into a re-aspiration group, who underwent repeat US-FNA within 6 months for a discordant pathological and clinico-radiological result, and a follow-up aspiration group, who underwent repeat US-FNA after 6 months without any clinical or radiological suspicion. The cancer rate in each group and the US findings of the later-diagnosed malignant nodules were assessed.

RESULTS

Nine malignancies were verified in the 187 cases (4.8%) by repeat US-FNA or surgery. In 44 patients in the re-aspiration group, 6 malignancies were identified (13.6%), compared with 3 malignancies in the 143 patients in the follow-up aspiration group (2.1%) (P<0.05). The later-diagnosed malignant nodules were an average of 1.0 cm in diameter; 66.7% were round; 66.7% were circumscribed; 100% were solid; 88.9% were hypoechoic; and 55.6% contained calcifications on US.

CONCLUSION

The follow-up of nodules with benign cytological diagnosis without clinicoradiological suspicion of malignancy is warranted using imaging surveillance rather than repeated US-FNA.

Fgf receptor signaling plays a role in lens induction

We describe experiments showing that fibroblast growth factor receptor (Fgfr) signaling plays a role in lens induction. Three distinct experimental strategies were used: (1) using small-molecule inhibitors of Fgfr kinase activity, we showed that both the transcription level and protein expression of Pax6, a transcription factor critical for lens development, was diminished in the presumptive lens ectoderm; (2) transgenic mice (designated Tfr7) that expressed a dominant-negative Fgf receptor exclusively in the presumptive lens ectoderm showed defects in formation of the lens placode at E9.5 but in addition, showed reduced levels of expression for Pax6, Sox2 and Foxe3, all markers of lens induction; (3) by performing crosses between Tfr7 transgenic and Bmp7-null mice, we showed that there is a genetic interaction between Fgfr and Bmp7 signaling at the induction phases of lens development. This manifested as exacerbated lens development defects and lower levels of Pax6 and Foxe3 expression in Tfr7/Tfr7, Bmp7+/– mice when compared with Tfr7/Tfr7 mice alone. As Bmp7 is an established lens induction signal, this provides further evidence that Fgfr activity is important for lens induction. This analysis establishes a role for Fgfr signaling in lens induction and defines a genetic pathway in which Fgfr and Bmp7 signaling converge on Pax6 expression in the lens placode with the Foxe3 and Sox2 genes lying downstream.

Role of the aryl hydrocarbon receptor in the development of control and 2,3,7,8-tetrachlorodibenzo-p-dioxin-exposed male mice

Experiments were conducted to determine the role of the aryl hydrocarbon receptor (AhR) in the development of control and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-exposed C57Bl/6 male mice. Male and female mice heterozygous for the AhR (Ahr+/-) were mated, and pregnant females were dosed orally on gestation day 13 with corn oil vehicle or TCDD (5 microg/kg). Pups were necropsied on postnatal day (PND) 21, 35, and 90. Comparison of vehicle-exposed wild-type (Ahr+/+) pups with vehicle-exposed AhR knockout (AhRKO; Ahr-/-) pups confirmed and extended previous reports that development of the liver, heart, spleen, thymus, and kidney is affected by absence of the AhR. Lung, submandibular gland, testis, and epididymis weights were also affected, indicating that the AhR plays a role in normal development of these organs as well. The presence or absence of the AhR had no effect on the incidence of hydronephrosis, daily sperm production, or cauda epididymal sperm numbers in vehicle-exposed mice. TCDD caused numerous effects in wild-type mice that were absent in AhRKO mice; specifically, hydronephrosis, increases in relative liver and heart weight, decreases in absolute heart and lung weight, and decreases in absolute and relative thymus, submandibular gland, epididymis, and testis weight. In several cases, TCDD produced one effect in wild-type mice (reductions in body weight and absolute thymus, submandibular gland, and epididymis weight on PND 21; and reductions in absolute and relative submandibular gland and absolute testis weight on PND 35) but caused the opposite effect in AhRKO mice. In yet other cases (reduced relative spleen weight on PND 21 and reductions in absolute and relative thymus weight on PND 35), TCDD produced similar effects in wildtype and AhRKO mice. There were also cases in which TCDD significantly affected AhRKO mice without significantly altering the same endpoint in wild-type mice; absolute liver, lung, and kidney weight were increased and relative submandibular gland weight was decreased on PND 21; relative heart weight was reduced and absolute lung weight increased on PND 35; and relative liver weight was decreased on PND 90. Although many effects of TCDD required the presence of the AhR, these results provide evidence either for multiple forms of the AhR in mice (one or more of which are still present in AhRKO mice), or for AhR-independent effects of low-level TCDD exposure.

Recurrent bleeding from a duodenal diverticulum 8 years after endoscopic treatment: case report and review of the literature

A 70-year-old woman presented with a 2-day history of tarry stool. She had a history of hemorrhage from a duodenal diverticulum of the 2nd portion 8 years previously that had been managed successfully by endoscopic hemostasis. Initial gastrointestinal endoscopy revealed ulceration of the diverticulum with no active bleeding; nevertheless the ulceration was presumed to be the source of the tarry stool. Despite medical treatment, bleeding started again, but endoscopic ethanol injection achieved hemostasis. When bleeding started yet again 8 days after the endoscopic therapy, the patient underwent diverticulectomy. Although duodenal diverticula are frequently found in the adult gastrointestinal tract, they rarely show hemorrhage. Recently, there has been controversy about whether bleeding diverticula should be managed surgically or endoscopically. We describe for the first time a rare case of recurrent hemorrhage of a duodenal diverticulum after an 8-year interval; the case was treated by surgical diverticulectomy as a definitive therapy for the recurrent bleeding ulcer. We also present a review of the literature.

Resection of liver metastasis after a pancreatoduodenectomy for pancreatic cancer: a case report

A case of resected liver metastasis from pancreatic cancer, in a 69-year-old woman who obtained a relatively long survival, is presented. Primary pancreatic cancer was found in a patient presenting with obstructive jaundice and a loss of appetite. A pylorus-preserving pancreatoduodenectomy was carried out on December 2, 1996. Eleven months later, a 1.5-cm mass was found in the right posterior segment of the liver. Although the tumor size had increased to 2.5 cm 5 months later, no other metastases were observed. Therefore, the right posterior segment of the liver was resected. Eleven months after the second operation, recurrence was found in the cut surface of the liver and the left caudate lobe. She died on May 1, 1999. This case demonstrated a relatively favorable prognosis in comparison to other common type of liver metastasis from pancreatic cancer. This study discusses the peculiarities of this case and emphasizes the necessity to carefully select the patients before attempting to resect the liver metastasis from pancreatic cancer.

Abnormalities of sexual development in male rats with in utero and lactational exposure to the antiandrogenic plasticizer Di(2-ethylhexyl) phthalate

Several members of the phthalate ester family have antiandrogenic properties, yet little is known about how exposure to these ubiquitous environmental contaminants early in development may affect sexual development. We conducted experiments to determine effects of in utero and lactational exposure to the most prevalent phthalate ester, di(2-ethylhexyl) phthalate (DEHP), on male reproductive system development and sexual behavior. Sprague-Dawley rats were dosed with corn oil or DEHP (0, 375, 750, or 1,500 mg/kg/day, per os) from gestation day 3 through postnatal day (PND) 21. Dose-related effects on male offspring included reduced anogenital distance, areola and nipple retention, undescended testes, and permanently incomplete preputial separation. Testis, epididymis, glans penis, ventral prostate, dorsolateral prostate, anterior prostate, and seminal vesicle weights were reduced at PND 21, 63, and/or 105-112. Additional dose-related effects included a high incidence of anterior prostate agenesis, a lower incidence of partial or complete ventral prostate agenesis, occasional dorsolateral prostate and seminal vesicle agenesis, reduced sperm counts, and testicular, epididymal, and penile malformations. Many DEHP-exposed males were sexually inactive in the presence of receptive control females, but sexual inactivity did not correlate with abnormal male reproductive organs. These results suggest that in utero and lactational DEHP exposure also inhibited sexually dimorphic central nervous system development. No major abnormalities were found in any of eight control litters, but DEHP caused severe male reproductive system toxicity in five of eight litters at 375 mg/kg/day, seven of eight litters at 750 mg/kg/day, and five of five litters at 1,500 mg/kg/day. These results demonstrate that the male reproductive system is far more sensitive to DEHP early in development than when animals are exposed as juveniles or adults. The effects of DEHP on male reproductive organs and sexual behaviors and the lack of significant effects on time to vaginal opening and first estrus in their littermates demonstrate that DEHP (and/or its metabolites) affects development of the male reproductive system primarily by acting as an antiandrogen. The pattern of effects of in utero and lactational DEHP exposure differed from patterns caused by other phthalate esters, and the preponderance of anterior prostate agenesis appears to be unique among all chemicals. These results suggest that DEHP acts partly by mechanisms distinct from those of other antiandrogens.

Resection of liver metastasis from gastric adenocarcinoma

BACKGROUND/AIMS

To determine the factors influencing the prognosis of patients undergoing resection of liver metastases from gastric adenocarcinoma.

METHODOLOGY

Over a 10-year period, at Kiryu Kousei General Hospital, 12 patients underwent potentially curative hepatectomy for metastatic adenocarcinoma of gastric origin. Two patients were excluded from this study, one because of postoperative death and one due to insufficient follow-up. We retrospectively examined the following factors: including TNM classification of the primary tumor, disease-free interval between gastric and hepatic resection, number and maximum diameter of the metastases, histological differentiation of the metastases, and the presence of lymphocyte aggregation enclosing the metastatic lesions. Survival rates were estimated by the Kaplan-Meier method and the weighting of each factor was compared by the log-rank test.

RESULTS

The overall 5-year survival rate of the 10 patients was 10%. The median survival time after hepatectomy was 16.3 months, ranging from 3.1 to 245.7 months. Eight patients died of recurrent cancer and 1 died of unrelated septic shock with no evidence of cancer recurrence. Only one patient was alive without recurrence at the time of maximum follow-up. A significant survival advantage was noted in patients with disease-free interval > or = 1 year, and those with metastatic tumors < 5 cm in maximum diameter and/or enclosed by the aggregated lymphocytes, when compared with patients with disease-free interval < 1 year and those with metastatic tumors > or = 5 cm and/or directly infiltrated hepatic parenchyma.

CONCLUSIONS

It was suggested that hepatectomy should be attempted in patients where the disease-free interval was > or = 1 year and with metastatic nodules < 5 cm. Lymphocyte aggregation around the metastatic tumor is a good prognostic sign for long-term survival.

Unique distribution of the anion exchange protein in the sea lamprey, Petromyzon marinus

The purpose of the present study was to examine the distribution of the anion exchange protein in the sea lamprey. Southern blots showed that genomic DNA of juvenile lampreys possesses several regions that are similar to segments of the AE gene from other vertebrates. However, physiological experiments examining rapid anion fluxes across the red blood cell (rbc) membrane and molecular experiments examining mRNA transcript levels both indicated that the anion exchange protein is absent in sea lamprey rbcs. In contrast, lamprey kidney, skeletal muscle, liver and heart tissue all appeared to possess mRNA transcripts for an AE protein. Further evidence for the presence of an AE protein in kidney tissue was obtained from Western blots. In order to evaluate the impact of the apparent rbc anion exchange limitations, the bicarbonate permeability of lamprey rbcs was also evaluated using mass spectrometry. The bicarbonate permeability of the lamprey rbc membrane was an order of magnitude lower than that of trout rbcs. Taken together, these results indicate that the gene for the AE protein is indeed present in lampreys, but it is not expressed in the rbc. Moreover, the process of CO2 transport in lamprey probably does not involve bicarbonate transport across the rbc membrane.

Abnormal expression of BRCA1 and BRCA1-interactive DNA-repair proteins in breast carcinomas

Breast cancer is one of the most common malignancies among women. The molecular mechanisms involved in breast carcinogenesis, however, remain to be elucidated. Although somatic mutation of BRCA1 is rare, BRCA1 protein expression is reduced in about 30% of sporadic breast carcinomas (Yoshikawa et al., Clin. Cancer Res., 5:1249-1261, 1999), indicating its possible involvement even in sporadic breast carcinogenesis. Among the BRCA1-interactive proteins are hRAD51 (a human homologue of Escherichia coli rec A protein), BARD1 (BRCA1-associated RING domain 1) and p53, all of which are involved in DNA repair. We have analyzed the expression patterns of the hRAD51, BARD1 and p53 proteins in five breast cancer cell lines, including a BRCA1-deficient cell line, and in 179 breast cancer tissue samples from Japanese women, including 113 sporadic, 47 hereditary (i.e., BRCA1 status unknown), and 19 BRCA1-associated cases. Of the 179 breast carcinomas, fifty-four (30%) exhibited reduced hRAD51 expression, and sixty-two (35%) exhibited p53 overexpression. On the other hand, reduced expression level of BARD1, and of hMSH2 and hMLH1, which are components of DNA mismatch-repair pathway and are involved in colorectal carcinogenesis, was observed respectively in only 10 (6%), 8 (5%) and 3 (2%) cases. The overall frequency of sporadic breast carcinomas with abnormal expression of either BRCA1 or the BRCA1-interactive proteins was 67% (76/113). These results indicate that there may be an important role for the BRCA1-associated DNA-repair pathway, not only in BRCA1-associated breast carcinomas, but also in sporadic breast carcinomas.

Retinoblastoma protein-initiated cellular growth arrest overcomes the ability of cotransfected wild-type p53 to induce apoptosis

The retinoblastoma gene, RB, participates in the regulation of the G1/S-phase transition and in p53-mediated apoptosis. We have previously reported that stably transfected RB functions as a growth and tumour suppressor in HTB9 human bladder carcinoma cells, which carry a mutation of the p53 gene at codon 280 and lack RB expression. To elucidate the potential role of RB in the regulation of p53-mediated apoptosis, we transfected a wt p53 expression plasmid under the control of the human cytomegalovirus promoter into parental and RB-transfected HTB9 cells. The p53(+)/RB(-)cells were susceptible to apoptosis under various experimental conditions: 1) incubation in serum-free culture for 72 h, 2) short-term (6 h) or long-term (48 h) exposure to etoposide, and 3) culturing in soft agar. In contrast, p53(+)/RB(+)cells were significantly resistant to apoptosis under similar conditions and exhibited efficient growth arrest, as measured by laser scanning cytometry. Tumorigenicity in nude mice of parental HTB9 cells was lost by exogenous expression of wt p53. Likewise, none of mice injected subcutaneously with either p53(-)/RB(+)or p53(+)/RB(+)cells developed tumours, indicating that RB allows suppression of tumorigenesis, regardless of p53 status. These results suggest that the growth-inhibitory function of RB may overcome the ability of wt p53 to induce apoptosis.

Correction of crooked nail deformity by modified osteoplastic reconstruction

To correct crooked nail deformity, which results from the partial loss of the distal phalanx, soft-tissue restoration alone is usually not enough to restore the length and shape of the nail structure. The authors treated 10 crooked nail fingertips by modified osteoplastic reconstruction, which included the elevation of the dorsally based volar skin flap and an iliac bone graft covered by an adequate skin flap. During the postoperative follow-up, the nail straightened, although not to the preinjury extent, along the restored distal phalanx with bony support. The authors' osteoplastic reconstruction, which involves the enhancement of the fingertips with composite tissues, presents a practical method for the correction of crooked nail deformity.

Activation of fibroblast-derived matrix metalloproteinase-2 by colon-cancer cells in non-contact Co-cultures

Stromal fibroblasts interact with invading cancer cells by secreting and activating matrix metalloproteinases (MMPs). To elucidate the mechanisms involved in the expression and activation patterns of MMPs, human colon-cancer cell lines Caco-2 and LoVo and colon-fibroblast cell line CCD18-Co were co-cultivated in non-contact and contact conditions which mimic in vivo interaction between cancer cells and fibroblasts before and after cancer invasion respectively. Gelatin zymography disclosed that MMP-2 was secreted from the fibroblasts but not from the cancer cells. The quantity of fibroblast-derived MMP-2 in conditioned medium was not significantly changed in either the contact or the non-contact co-cultures when compared with that of individual cultures of CCD18-Co fibroblasts. Cancer cells in non-contact co-cultures, however, enhanced the activation of fibroblast-derived MMP-2. Transcripts of membrane-type matrix metalloproteinase-1 (MT1-MMP), which is thought to be present on the cell surface and to work as a candidate activator of MMP-2, were detected in both cancer cell lines. Plasma membrane extracts of cancer cells also activated MMP-2 in conditioned media in cell-free conditions. This activation of MMP-2 may be caused by MT1-MMP of the cancer cells, since it was inhibited by a series of MMP inhibitors, including ethylenediaminetetraacetic acid (EDTA), the tissue inhibitor of metalloproteinase-2 (TIMP-2), and the MMP inhibitor CGS 27023A, but not by TIMP-1. Our data demonstrate that in non-contact co-cultures colon-cancer cells activate fibroblast-derived MMP-2 on their plasma membranes. These findings should help to elucidate the mechanism involved in the initial destruction of basement membrane by cancer cells.

Disrupted transforming growth factor-beta signaling and deregulated growth in human biliary tract cancer cells

Biliary tract carcinoma is a common neoplasm in Japan, and its treatment is difficult because it tends to promote fibrosis and easily invades surrounding tissues. To better characterize the biological features of this carcinoma, we investigated abnormalities in the transforming growth factor-beta (TGF-beta) signaling pathway in five human biliary tract cancer cell lines: RBE, KMBC, SK-ChA-1, Mz-ChA-1, and Mz-ChA-2. We stably transfected into these cells the luciferase reporter plasmid carrying promoter of the plasminogen activator inhibitor-1 gene, the expression of which is stimulated by TGF-beta1. Treating the KMBC and Mz-ChA-1 cells with TGF-beta1 neither inhibited cell growth nor stimulated luciferase activity. In contrast, the RBE and Mz-ChA-2 cells responded well to TGF-beta1 treatment. TGF-beta1-treated SK-ChA-1 cells exhibited attenuated luciferase activity and their growth was not inhibited. Smad4 mRNA was not detected in SK-ChA-1 and Mz-ChA-1 cells by Northern blot analysis. Genetic analysis disclosed a nonsense mutation in the Mad homologue 2a domain of the Smad4 gene in the SK-ChA-1 cells and a heterozygous deletion in the TGF-beta type II receptor gene in the KMBC cells. Expression of the exogenous Smad4 gene in the Mz-ChA-1 cells by transient transfection restored their luciferase activity. When these TGF-beta1-insensitive and less-TGF-beta1-sensitive cell lines were xenografted into nude mice, they developed tumors that had more prominent, intervening fibrosis (desmoplasia) than the tumors caused by TGF-beta1-sensitive cells. Thus, a tight correlation between disruption of the TGF-beta signaling pathway and deregulated growth of cancer cells has been demonstrated in biliary tract carcinoma. This seems to be a critical event in this carcinoma and may also be correlated with stromal cell reaction in cancer invasion.

Biochemical and functional characterization of intercellular adhesion and gap junctions in fibroblasts

Despite their significance in wound healing, little is known about the molecular determinants of cell-to-cell adhesion and gap junctional communication in fibroblasts. We characterized intercellular adherens junctions and gap junctions in human gingival fibroblasts (HGFs) using a novel model. Calcein-labeled donor cells in suspension were added onto an established, Texas red dextran (10 kDa)-labeled acceptor cell monolayer. Cell-to-cell adhesion required Ca(2+) and was >30-fold stronger than cell-to-fibronectin adhesion at 15 min. Electron micrographs showed rapid formation of adherens junction-like structures at approximately 15 min that matured by approximately 2-3 h; distinct gap junctional complexes were evident by approximately 3 h. Immunoblotting showed that HGF expressed beta-catenin and that cadherins and connexin43 were recruited to the Triton-insoluble cytoskeletal fraction in confluent cultures. Confocal microscopy localized the same molecules to intercellular contacts of acceptor and donor cells. There was extensive calcein dye transfer in a cohort of Texas red dextran-labeled cells, but this was almost completely abolished by the gap junction inhibitor beta-glycyrrhetinic acid and the connexin43 mimetic peptide GAP 27. This donor-acceptor cell model allows large numbers (>10(5)) of cells to form synchronous cell-to-cell contacts, thereby enabling the simultaneous functional and molecular studies of adherens junctions and gap junctions.