Ovarian squamous cell carcinoma associated with teratoma: a report of six cases with genomic analysis

Ovarian squamous cell carcinoma (SCC), particularly the sarcomatoid variant, arising from teratoma is a rare malignant tumour with unfavourable clinical outcomes. Its molecular genetic alterations have not been well-documented to date. This study aims to characterise the molecular features and to provide potential therapeutic targets in this rare entity. We analysed the clinicopathological and immunohistochemical features of six primary ovarian SCC. These cases were subject to targeted next-generation sequencing to detect genomic features. We found that all six ovarian SCC (four conventional and two sarcomatoid SCC) were associated with mature cystic teratomas. Patient 3 (FIGO stage IIIa) and Patient 4 (stage IIb) died of disease at 10 and 11 months, respectively. The remaining patients (three with stage I and one with IIc) including the two with sarcomatoid SCC, were alive with no evidence of disease at 28-72 months. All patients showed PD-L1 expression (tumour proportion score: range 10-78%, median 41%; combined positive score: range 12-85, median 42) and a high tumour mutation burden (range 13.4-25.7 mutations/Mb, median 16.5). The most frequently recurrent mutations included PIK3CA (4/6), TP53 (4/6), TERT promoter (4/6), CDKN2A (3/6). Mutations in homologous recombination repair pathway genes (BLM, ATM, BRCA1, BRIP1 and ATM) were found in 5/6 patients. The sarcomatoid SCC shared a similar mutational profile with conventional SCC, and no recurrent genetic mutations exclusively in sarcomatoid SCC were identified. Our study suggests the potential benefits of immune checkpoint inhibitors and/or PARP inhibitors in patients with primary ovarian SCC on account of PD-L1 expression and genomic features. Ovarian sarcomatoid SCC may be clonally related to the conventional SCC. A multiple-institutional, clinical and molecular study will consolidate these findings in the future.

Coalescence dynamics of 3D islands on weakly-interacting substrates

We use kinetic Monte Carlo simulations and analytical modelling to study coalescence of three-dimensional (3D) nanoscale faceted silver island pairs on weakly-interacting fcc(111) substrates, with and without concurrent supply of mobile adatoms from the vapor phase. Our simulations show that for vapor flux arrival rates F < 1 monolayer/second (ML/s) coalescence manifests itself by one of the islands absorbing the other via sidewall facet migration. This process is mediated by nucleation and growth of two-dimensional (2D) layers on the island facets, while the supply of mobile atoms increases the nucleation probability and shortens the time required for coalescence completion. When F is increased above 1 ML/s, coalescence is predominantly governed by deposition from the vapor phase and the island pair reaches a compact shape via agglomeration. The crucial role of facets for the coalescence dynamics is further supported by a mean-field thermodynamic description of the nucleation energetics and kinetics. Our findings explain experimental results which show that two-dimensional film growth morphology on weakly-interacting substrates is promoted when the rate of island coalescence is suppressed. The present study also highlights that deviations of experimentally reported film morphological evolutions in weakly-interacting film/substrate systems from predictions based on the sintering and particle growth theories may be understood in light of the effect of deposition flux atoms on the energetics and kinetics of facet-layer nucleation during coalescence.

Increased circulating GrMyeloid-derived suppressor cells correlated with tumor burden and survival in locally advanced cervical cancer patient

Background: Myeloid-derived suppressor cells (MDSCs) may lead to immune evasion and disease progression in some cancers, but their roles remain to be investigated in cervical cancer. This study aimed to characterize the specific subsets of MDSCs that might be potential indicators for disease progression in cervical cancer patients. Methods: Different subsets of MDSCs were characterized using flow cytometry in blood samples from healthy subjects and cervical cancer patients. T-cell proliferation assay was performed in vitro. Tumor infiltrating CD8+ and FOXP3+ cells were also evaluated by immunostaining on the tumor tissues from patients with early and locally advanced cervical cancer. We further analyzed the relevance of circulating MDSCs to clinicopathological characteristics, patient survival as well as tumor infiltrating lymphocytes. Results: The frequency of circulating GrMDSCs increased correlated with FIGO stage while the percentage of MoMDSCs only elevated in patients with advanced cervical cancers. For patients with early and locally advanced cervical cancer, the frequency of circulating GrMDSCs but not MoMDSCs correlated with clinicopathologic parameters including metastatic lymph nodes, deep stromal invasion and tumor recurrence. The levels of circulating GrMDSCs also negatively correlated with the densities of CD8+ cells in tumor tissues. In vitro assay showed that Gr-MDSCs suppressed the proliferation of autologous T cells. Conclusion: Our study demonstrates that the increased frequency of circulating GrMDSCs is associated with tumor burden and recurrence in early and locally advanced cervical cancer patients, that the GrMDSCs may be potential biomarkers for disease progression cervical cancers.

Tumor-infiltrating CD8+ and FOXP3+ lymphocytes before and after neoadjuvant chemotherapy in cervical cancer

Background

Neoadjuvant chemotherapy (NACT) has been recently accepted as an effective alternative in patients with locally advanced cervical cancer. However, little is known about the effects of NACT on the immunological microenvironment in cervical cancers. In this study, we analyzed the alterations of tumor infiltrating lymphocytes (TILs) before and after NACT and analyzed their prognostic significance in advanced cervical cancer patients treated with platinum-based NACT.

Methods

We recruited 137 patients with stage Ib2 and IIa2 cervical cancer retrospectively. Pretreatment biopsy and surgical specimens after NACT were immunostained with CD8 and Foxp3. The densities of intratumoral and peritumoral immunopositive TILs were analyzed separately.

Results

Foxp3+ T cells density significantly decreased in both intratumoral (median 28.49 vs. 19.97; Z = − 8.635, p < 0.001) and peritumoral (median 113.53 vs. 82.48; Z = − 3.741, p < 0.001) areas after NACT, whereas CD8+ T cell counts remained stable in both intratumoral (median 121.32 vs. 109.59; Z = − 0.817,p = 0.414) and peritumoral (median 402.56 vs. 390.84; Z = − 1.138,p = 0.255) areas. Patients with pathological complete response (pCR) had significantly lower number of Foxp3+ T cell density after NACT than non-pCR cases in both intratumoral (median16.12 vs. 22.00; Z = − 2.009, p = 0.045) and peritumoral areas(median 63.31 vs. 98.48; Z = − 2.469, p = 0.014). Multivariate analyses demonstrated that high ratio of intratumoral CD8/peritumoral Foxp3 in residual tumors was independent prognostic factor for both progression-free survival (HR = 0.297; 95% CI, 0.109–0.810, p = 0.018) and overall survival (HR = 0.078; 95% CI, 0.010–0.598, p = 0.014).

Conclusions

NACT in cervical cancers can induce anti-cancer immunity by altering TILs subsets. An elevated intratumoral CD8/peritumoral Foxp3 ratio after NACT may confer a favorable clinical outcome.

[Feasibility of device closure for multiple atrial septal defects using 3D printing and ultrasound-guided intervention technique]

Objective: To investigate the feasibility of trans-catheter closure of multiple atrial septal defects (ASD) monitored by trans-thoracic echocardiography (TTE) under the guidance of 3D printing heart model. Methods: Between April and August 2016, a total of 21 patients (8 male and 13 female) with multiple ASD in Fuwai Hospital of Chinese Academy of Medical Sciences underwent CT scan and 3-dimensional echocardiography for heart disease model produced by 3D printing technique. The best occlusion program was determined through the simulation test on the model. Percutaneous device closure of multiple ASD was performed follow the predetermined program guided by TTE. Clinical follow-up including electrocardiogram and TTE was arranged at 1 month after the procedure. Results: The trans-catheter procedure was successful in all 21 patients using a single atrial septal occluder. Mild residual shunt was found in 5 patient in the immediate postoperative period, 3 of them were disappeared during postoperative follow-up. There was no death, vascular damage, arrhythmia, device migration, thromboembolism, valvular dysfunction during the follow-up period. Conclusion: The use of 3D printing heart model provides a useful reference for transcatheter device closure of multiple ASD achieving through ultrasound-guided intervention technique, which appears to be safe and feasible with good outcomes of short-term follow-up.

[Changes of adherens junctions between the epithelial cells of intestinal mucosal barrier in irritable bowel syndrome]

Objective: To investigate whether there are changes in adherens junctions(AJ), including E-cadherin (E-cad) and β-catenin (β-cat), in the colonic mucosa of irritable bowel syndrome (IBS). Methods: Colorectal dilatation combined with restraint stress was used to establish IBS SD rat model. There were 8 rats in the model group and 8 rats in normal control group. From each rat, the colon tissue 5 centimeters away from ileocecum (I) and the junction of the rectum and sigmoid colon (R) were taken, in which E-cad and β-cat mRNA, protein level and structural changes were detected using real-time quantitative-PCR, Western blot, and immunofluorescence. According to the Rome Ⅲ criteria, IBS with diarrhea (IBS-D) patients receiving colonoscopy (n=17) and healthy volunteers (n=17) were enrolled in Center of Endoscopy of the First Affiliated Hospital of Zhejiang Chinese Medicine University. The colon tissues of I and R locations were collected from them. Colonic epithelial cell AJ protein expression and AJ structural changes in the tissues were detected using Western blot, immunofluorescence and transmission electron microscope (TEM). Results: (1)Both in I and R sites, the mRNA and protein expression of E-cad in IBS rats were both significantly lower than in normal SD rats (all P<0.05). The mRNA expression of β-cat showed no significant change in IBS SD rats compared with the normal SD rats; the protein expression of β-cat was decreased in I(P<0.05), no significantly different in R. (2)In I and R of IBS-D patients, the expression of E-cad protein were significantly decreased(I: 0.85±0.30 vs 1.24±0.34, P=0.00; R: 0.86±0.17 vs 1.14±0.48, P=0.05); the protein expression of β-cat also showed significant reduction both in I(0.85±0.39 vs 1.22±0.51, P=0.04)and R (0.92±0.22 vs 1.16±0.31, P=0.02) of IBS-D patients, compared with the healthy controls. Immunofluorescence results showed that E-cad and β-cat in colonic epithelial cells of I and R in the healthy controls were distributed along the cell membrane, demonstrating honeycomb linear fluorescence; however, in IBS-D patients, the structure of E-cad and β-cat were fuzzy, with disrupted distribution in the cytoplasm. Under TEM, the gaps of AJ in I and R of IBS-D patients appeared wider than in the healthy volunteers. Conclusions: In IBS-D patients, there are wider gaps of AJ, and decreased expression with structural disorder of E-cad and β-cat in the colon. The change of AJ plays an important role in the damage of colonic mucosal barrier and the increase of intestinal epithelial permeability in IBS-D patients, but the mechanism is yet to be further explored.

Numerical comparison of acoustic wedge models, with application to ultrasonic telemetry

Ultrasonic telemetry imaging systems are used to monitor such immersed structures as main vessels of nuclear reactors. The interaction between acoustic beams and targets involves scattering phenomena, mainly specular reflection and tip diffraction. In order to assist in the design of imaging systems, a simulation tool is required for the accurate modeling of such phenomena. Relevant high-frequency scattering models have been developed in electromagnetic applications, in particular, the geometrical optics (GO), Geometrical Theory of Diffraction (GTD) and its uniform corrections (UAT and UTD), Kirchhoff approximation (KA) and Physical Theory of Diffraction (PTD). Before adopting any of them for simulation of scattering of acoustic waves by edged immersed rigid bodies, it is important to realize that in acoustics the characteristic dimension to the wave length ratio is usually considerably smaller than in electromagnetics and a further study is required to identify models' advantages, disadvantages and regions of applicability. In this paper their numerical comparison is carried out. As the result, the most suitable algorithm is identified for simulating ultrasonic telemetry of immersed rigid structures.

Overexpression of AT14A confers tolerance to drought stress-induced oxidative damage in suspension cultured cells of Arabidopsis thaliana

Drought stress can affect interaction between plant cell plasma membrane and cell wall. Arabidopsis AT14A, an integrin-like protein, mediates the cell wall-plasma membrane-cytoskeleton continuum (WMC continuum). To gain further insight into the function of AT14A, the role of AT14A in response to drought stress simulated by polyethylene glycol (PEG-6000) in Arabidopsis suspension cultures was investigated. The expression of this gene was induced by PEG-6000 resulting from reverse transcription-PCR, which was further confirmed by the expression data from publically available microarray datasets. Compared to the wild-type cells, overexpression of AT14A (AT14A-OE) in Arabidopsis cultures exhibited a greater ability to adapt to water deficit, as evidenced by higher biomass accumulation and cell survival rate. Furthermore, AT14A-OE cells showed a higher tolerance to PEG-induced oxidative damage, as reflected by less H2O2 content, lipid peroxidation (malondialdehyde (MDA) content), and ion leakage, which was further verified by maintaining high levels of activities of antioxidant defense enzymes such as ascorbate peroxidase and guaiacol peroxidase and soluble protein. Taken together, our results suggest that overexpression of AT14A improves drought stress tolerance and that AT14A is involved in suppressing oxidative damage under drought stress in part via regulation of antioxidant enzyme activities.

TCF7L2 gene polymorphisms and type 2 diabetes risk: a comprehensive and updated meta-analysis involving 121,174 subjects

Recently, many new loci associated with type 2 diabetes have been uncovered by genetic association studies and genome-wide association studies. As more reports are made, particularly with respect to varying ethnicities, there is a need to determine more precisely the effect sizes in each major racial group. In addition, some reports have claimed ethnic-specific associations with alternative single-nucleotide polymorphisms (SNPs), and to that end there has been a degree of confusion. We conducted a meta-analysis using an additive genetic model. Eight polymorphisms in 155 studies with 121174 subjects (53385 cases and 67789 controls) were addressed in this meta-analysis. Significant associations were found between type 2 diabetes and rs7903146, rs12255372, rs11196205, rs7901695, rs7895340 and rs4506565, with summary odds ratios (ORs) (95% confidence interval) of 1.39 (1.34-1.45), 1.33 (1.27-1.40), 1.20 (1.14-1.26), 1.32 (1.25-1.39), 1.21 (1.13-1.29) and 1.39 (1.29-1.49), respectively. In addition, no significant associations were found between the two polymorphisms (rs290487 and rs11196218) and type 2 diabetes. The summary ORs for the six statistically significant associations (P < 0.05) were further evaluated by estimating the false-positive report probability, with results indicating that all of the six significant associations were considered noteworthy, and may plausibly be true associations. Significant associations were found between the six polymorphisms (rs7903146, rs12255372, rs11196205, rs7901695, rs7895340 and rs4506565) in the TCF7L2 gene and type 2 diabetes risk, and the other two polymorphisms (rs11196218 and rs290487) were not found to be significantly associated with type 2 diabetes. Subgroups analyses show that significant associations are not found between the six SNPs (rs7903146, rs12255372, rs11196205, rs7901695, rs7895340, and rs4506565) and the type 2 diabetes in some ethnic populations.

TCF7L2 gene polymorphisms and type 2 diabetes risk: a comprehensive and updated meta-analysis involving 121,174 subjects

Recently, many new loci associated with type 2 diabetes have been uncovered by genetic association studies and genome-wide association studies. As more reports are made, particularly with respect to varying ethnicities, there is a need to determine more precisely the effect sizes in each major racial group. In addition, some reports have claimed ethnic-specific associations with alternative single-nucleotide polymorphisms (SNPs), and to that end there has been a degree of confusion. We conducted a meta-analysis using an additive genetic model. Eight polymorphisms in 155 studies with 121174 subjects (53385 cases and 67789 controls) were addressed in this meta-analysis. Significant associations were found between type 2 diabetes and rs7903146, rs12255372, rs11196205, rs7901695, rs7895340 and rs4506565, with summary odds ratios (ORs) (95% confidence interval) of 1.39 (1.34-1.45), 1.33 (1.27-1.40), 1.20 (1.14-1.26), 1.32 (1.25-1.39), 1.21 (1.13-1.29) and 1.39 (1.29-1.49), respectively. In addition, no significant associations were found between the two polymorphisms (rs290487 and rs11196218) and type 2 diabetes. The summary ORs for the six statistically significant associations (P < 0.05) were further evaluated by estimating the false-positive report probability, with results indicating that all of the six significant associations were considered noteworthy, and may plausibly be true associations. Significant associations were found between the six polymorphisms (rs7903146, rs12255372, rs11196205, rs7901695, rs7895340 and rs4506565) in the TCF7L2 gene and type 2 diabetes risk, and the other two polymorphisms (rs11196218 and rs290487) were not found to be significantly associated with type 2 diabetes. Subgroups analyses show that significant associations are not found between the six SNPs (rs7903146, rs12255372, rs11196205, rs7901695, rs7895340, and rs4506565) and the type 2 diabetes in some ethnic populations.

SVM-T-RFE: a novel gene selection algorithm for identifying metastasis-related genes in colorectal cancer using gene expression profiles

Although metastasis is the principal cause of death cause for colorectal cancer (CRC) patients, the molecular mechanisms underlying CRC metastasis are still not fully understood. In an attempt to identify metastasis-related genes in CRC, we obtained gene expression profiles of 55 early stage primary CRCs, 56 late stage primary CRCs, and 34 metastatic CRCs from the expression project in Oncology (http://www.intgen.org/expo/). We developed a novel gene selection algorithm (SVM-T-RFE), which extends support vector machine recursive feature elimination (SVM-RFE) algorithm by incorporating T-statistic. We achieved highest classification accuracy (100%) with smaller gene subsets (10 and 6, respectively), when classifying between early and late stage primary CRCs, as well as between metastatic CRCs and late stage primary CRCs. We also compared the performance of SVM-T-RFE and SVM-RFE gene selection algorithms on another large-scale CRC dataset and the five public microarray datasets. SVM-T-RFE bestowed SVM-RFE algorithm in identifying more differentially expressed genes, and achieving highest prediction accuracy using equal or smaller number of selected genes. A fraction of selected genes have been reported to be associated with CRC development or metastasis.

-8p12-23 and +20q are predictors of subtypes and metastatic pathways in colorectal cancer: construction of tree models using comparative genomic hybridization data

A substantial body of evidence suggests the genetic heterogeneous pattern and multiple pathways in colorectal cancer initiation and progression. In this study, we construct a branching tree and multiple distance-based tree models to elucidate these genetic patterns and pathways in colorectal cancer by using a data set comprised of 244 cases of comparative genomic hybridization. We identify the six most common gains of chromosomal regions of 7p (37.0%), 7q11-32 (34.8%), 8q (48.3%), 13q (49.1%), 20p (36.1%), and 20q (50.4%), and the nine most common losses of 1p13-36 (30.9%), 4p15 (24.3%), 4q33-34 (24.3%), 8p12-23 (50.9%), 15q13-14 (23.5%), 15q24-25 (24.3%), 17p (34.8%), 18p (36.5%), and 18q (61.7%) in colorectal cancer. We classify colorectal cancer into two distinct groups: one preceding with -8p12-23, and the other with +20q. The sample-based classification tree also demonstrates that colorectal cancer can be classified into multiple subtypes marked by -8p12-23 and +20q. By comparing chromosomal abnormalities between primary and metastatic colorectal cancer, we identify five potential metastatic pathways: (-18q, -18p), (-8p12-23, -4p15, -4q33-34), (+20q, +20p), (+20q, +7p, +7q11-32), and +8q. -8p12-23 and +20q are inferred to be the two marker events of colorectal cancer metastasis. The current oncogenetic tree models may contribute to our understanding towards molecular genetics in colorectal cancer. Particularly, the metastatic pathways we describe may provide pivotal clues for metastatic candidate genes, and thus impact on the prediction and intervention of metastatic colorectal cancer.

Identification of serum biomarkers for colorectal cancer metastasis using a differential secretome approach

Lymph node metastasis is the major concern that causes death in colorectal cancers. However, biomarkers for cancer metastasis are still lacking. In this study, we applied an LC-MS/MS-based label-free quantitative proteomics approach to compare the differential secretome of a primary cell line SW480 and its lymph node metastatic cell line SW620 from the same colorectal cancer patient. We identified a total of 910 proteins from the conditioned media and 145 differential proteins between SW480 and SW620 (>1.5-fold change). The differential expression pattern of 6 candidate proteins was validated by Western blot analysis. Among them, trefoil factor 3 and growth/differentiation factor 15, two up-regulated proteins in SW620, were further analyzed in a large cohort of clinical tissue and serum samples. Sandwich ELISA assay showed that the serum levels of both proteins were significantly higher in lymph node metastatic colorectal cancers. Receiver operating characteristic curve analysis confirmed that serum trefoil factor 3 and growth/differentiation factor 15 could provide a discriminatory diagnostic test for predicting colorectal cancer metastasis. Immunohistochemical analysis also showed that the overexpression of trefoil factor 3 or growth/differentiation factor 15 in colorectal cancer was associated with lymph node metastatic behavior. This study showed an accurate, sensitive, and robust label-free quantitation approach for differential analysis of cancer secretome. The comparison of the cancer secretome in vitro is a feasible strategy to obtain valuable biomarkers for potential clinical application. Both trefoil factor 3 and growth/differentiation factor 15 could serve as potential biomarkers for the prediction of colorectal cancer metastasis.

The expressions of bHLH gene HES1 and HES5 in advanced ovarian serous adenocarcinomas and their prognostic significance: a retrospective clinical study

Purpose

Notch signaling was recently found to be associated with prognosis of some cancers. The aim of the study is to investigate significance of the expression of HES1/HES5 protein, downstream effectors of Notch, in prognosis of the patients with advanced ovarian epithelial cancers.

Methods

Formalin-fixed, paraffin embedded tissues and clinic-pathological parameters from 61 patients with FIGO stage IIIc–IV ovarian serous adenocarcinoma were collected, the expression of HES1 and HES5 protein were immunohistochemically detected, and the association of HES1 and HES5 expression with survival of the patients were analyzed.

Results

The expressions of both HES1 and HES5 in adenocarcinoma were significantly higher than those in adenoma and normal control (χ² = 32.915, P = 0.000 and χ² = 46.863, P = 0.000 respectively). Overall survival and disease-free period were longer in HES1 low-expression patients (median 43.0 and 22.0 months) than those in high-expression patients (median 24.0 and 14.5 months). Of those, Overall survival period of patients with HES1 low-expression was significantly longer than that of those with high-expression (χ² = 4.049, P = 0.044). Univariate analysis and multivariate Cox regression model did not show that HES1 or HES5 expression was a factor associated with survival of advanced ovarian serous adenocarcinoma patients.

Conclusions

The expressions of bHLH gene HES1 and HES5 are increased in advanced ovarian serous adenocarcinomas, and HES1 high-expression probably is a potential poor prognostic factor for the patients.

Analysis of SOX9 expression in colorectal cancer

Our purpose was to investigate the role of SOX9, a novel downstream molecule of beta-catenin, in colorectal cancer. Expression of SOX9 and beta-catenin was detected by immunostaining, quantitative real-time reverse transcription-polymerase chain reaction (Q-PCR), and Western blot in colorectal cancer. The correlation between SOX9 or beta-catenin expression and clinicopathologic parameters was also analyzed. Immunostaining, Q-PCR, and Western blot consistently confirmed SOX9 up-regulation in colorectal cancer compared with normal mucosa (P < .05). Immunostaining showed more SOX9+ cells in the lower zone of colonic crypts than in the upper zone (P < .05). Cancers with strong SOX9 immunostaining were significantly associated with a lower 5-year overall survival (40% [17/43] vs low expression, 69% [66/95]; P < .01). The Cox proportional hazards model showed that strong SOX9 expression was an independent adverse prognosticator in colorectal cancer (P < .05). The detection of SOX9 expression might contribute to predicting clinical outcomes for patients with colorectal cancer.

Downregulation of Krüppel-like factor 9 in human colorectal cancer

Mammalian Sp and Krüppel-like factors (KLF), a family of zinc finger-containing transcription factors, are involved in growth control, proliferation, apoptosis and angiogenesis of a wide variety of tissues and cells. Several KLF have been linked to various types of human cancers, but the relationship between Krüppel-like factor 9 (KLF9) and colorectal cancer has not been explored. The purpose of the present study was to investigate KLF9 expression in human colorectal cancer tissue. KLF9 mRNA was detected on quantitative real-time reverse transcriptase-polymerase chain reaction (Q-PCR). Of the 50 cancerous tissues examined, 86% (43/50) expressed lower levels of KLF9 mRNA than individually matched normal mucosa (P < 0.0001). On western blot, reduced or absent expression of KLF9 protein was observed in 65% (13/20) of the samples (P < 0.01). A total of 81% (35/43) of normal samples had expression of KLF9 protein, whereas its protein was detected in only 9% (4/43) of tumor tissues (P < 0.001) on tissue microarray. These results indicate that KLF9 may be involved in the carcinogenesis of human colorectal cancer.

Dynamic down-regulation of Krüppel-like factor 4 in colorectal adenoma-carcinoma sequence

PURPOSE

To explore the clinical significance of Krüppel-like factors 4 (KLF4) expression in colorectal cancer initiation and progression.

METHODS

We used quantitative real-time PCR to detect KLF4 mRNA expression in 49 colorectal cancer samples with individual-matched normal mucosa and eight concurrent adenomas. We also analysed the immunostaining pattern of KLF4 in additional 129 colorectal cancers and 48 sporadic colorectal adenomas with matched normal mucosa and correlated KLF4 staining with clinicopathological parameters and prognosis. KLF4 expression change was detected in SW480, SW620 and RKO cell lines after treatment of 5-aza-dC (10 microM) or butyrate sodium (4 mM).

RESULTS

The large clinicopathological survey with combined methods confirmed a dynamic downregulation of KLF4 in individual-matched normal mucosa, adenoma and cancer (P < 0.05). The quantitative analysis of immunostaining pattern showed that KLF4 staining cells were more frequently seen in the upper zones than that in the lower zones of both normal mucosa and adenoma (P < 0.05). Survival analysis implied a trend toward better overall survival in KLF4-positive colorectal cancer patients with lymph node metastasis than that in KLF4-negative cancer with lymph node metastasis. In vitro study found elevated KLF4 mRNA expression in SW620 and RKO cells with 5-aza-dC treatment, implicating the underlying aberrant epigenetic modifications in regulating KLF4 expression at least in a subset of colorectal cancers.

CONCLUSIONS

KLF4 is associated with terminal differentiation in colorectal epithelium and drastically downregulated in colorectal adenomas and cancers via possible epigenetic modifications. Loss of KLF4 protein expression might contribute to assessing prognosis in colorectal cancer with lymph node metastasis.

TaqMan low density array is roughly right for gene expression quantification in colorectal cancer

BACKGROUND

TaqMan low density array (LDA) is promising for high throughput screening in functional genomics by simultaneously measuring mRNA expression of multiple genes. However, the reproducibility and reliability remain to be explored.

METHODS

We applied LDA to detect mRNA expression of 95 gastrointestinal differentiation associated genes in 27 colorectal cancers with individual-matched normal mucosa. Conventional Q-PCR assay was done to detect 18 differentially expressed genes in additional 22 colorectal cancers.

RESULTS

A total of 97.2% (11,520/11,844) gene samples were successfully amplified by LDA. There was a perfect agreement between intra-LDA assays in all gene samples (CCC=0.952, p<0.0001). Seventy-nine genes showed perfect or substantial agreement between intra-LDA tests (CCC>0.713). Genes with low Ct values (<30 cycles) had more genes showing perfect agreement, less showing moderate agreement, and lower DeltaCt variances between intra-plate assays than that with high Ct values (>30 cycles) (p<0.01). All 18 genes showed the same directional changes in colorectal cancers versus normal mucosa by both SYBR Green and LDA approaches.

CONCLUSIONS

LDA is a roughly robust method for gene quantification in colorectal cancer, but its reproducibility decreased in low copy genes. Hence, we strongly recommend caution when analyzing LDA results of those low copy genes.

Differential expression of mimecan and thioredoxin domain-containing protein 5 in colorectal adenoma and cancer: a proteomic study

Adenoma is the major precursor lesion of colorectal cancer, one of the most common cancers worldwide. The elucidation of the molecular mechanism underlying adenoma is essential for early detection, prevention, and intervention of colorectal cancer. Using a combination of two-dimensional gel electrophoresis and mass spectrometry, we identified 27 differentially expressed proteins in adenoma, compared with matched normal mucosa and cancer tissue. Seventeen proteins were upregulated and six downregulated in adenoma when compared with the same proteins in individual-matched normal mucosa. Four were downregulated, but none upregulated in adenoma when compared with the same proteins in matched cancer tissue. Two novel proteins, mimecan and thioredoxin domain-containing protein 5 (TXNDC5), were further validated by Western blot in 8 colorectal adenomas and 19 cancers that were matched with normal mucosa. All adenoma and cancer tissues did not express mimecan, but all normal mucosa did (P < 0.01). In contrast, TXNDC5 was significantly upregulated in colorectal adenoma and cancer tissues as compared with that in normal mucosa (P < 0.05). This study clearly demonstrated that absence of mimecan and upregulation of TXNDC5 are involved in the early development of colorectal cancer. Thus, the differentially expressed proteins might serve as potential biomarkers for colorectal cancer detection and intervention.

Association of matrix metalloproteinase-2 and -9 promoter polymorphisms with colorectal cancer in Chinese

Matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) play an important role in cancer initiation, invasion, and metastasis. The aim of this study was to investigate whether common genetic variants in these two key MMPs are associated with the development and progression of colorectal cancer in a Chinese population. We detected the MMP-2-790T/G, -955A/C, -1575G/A, and MMP-9-1562 C/T polymorphisms in 126 colorectal cancer patients and matched normal controls by PCR-denaturing high-performance liquid chromatography (DHPLC) or PCR-restriction fragment length polymorphism (RFLP), respectively. We found that the G/G genotype in the MMP-2-1575G/A polymorphism was significantly increased in colorectal cancer patients than in the controls (odds ratio (OR), 1.96; 95% CI, 1.06-3.64). Colorectal cancers with G/G genotype were more common with serosa/adventitia layer involvement than those with G/A+A/A genotypes (P<0.05). However, no significant differences were observed in distribution of the MMP-2-790T/G, -955A/C, and MMP-9-1562 C/T polymorphisms or haplotype of MMP-2 SNPs between patients and controls. Our results suggest that the presence of -1575G allele in the MMP-2 promoter region may be of significance in the assessment of colorectal cancer risk and invasive potential.

Intracellular localization of integrin-like protein and its roles in osmotic stress-induced abscisic acid biosynthesis in Zea mays

Plants have evolved many mechanisms to cope with adverse environmental stresses. Abscisic acid (ABA) accumulates significantly in plant cells in response to drought conditions, and this is believed to be a major mechanism through which plants enhance drought tolerance. In this study, we explore the possible mechanisms of osmotic stress perception by plant cells and the consequent induction of ABA biosynthesis. Immunoblotting and immunofluorescence localization experiments, using a polyclonal antibody against human integrin beta1, revealed the presence of a protein in Zea mays roots that is similar to the integrin proteins of animals and mainly localized in the plasma membrane. Treatment with GRGDS, a synthetic pentapeptide containing an RGD domain, which interacted specifically with the integrin protein and thus blocked the cell wall-plasma membrane interaction, significantly inhibited osmotic stress-induced ABA biosynthesis in cells, and the GRGDS analog which does not contain the RGD domain had no effect. Our results show that a strong interaction exists between the cell wall and plasma membrane and that this interaction is largely mediated by integrin-like proteins. They also imply that the cell wall and/or cell wall-plasma membrane interaction plays important roles in the perception of osmotic stress. Accordingly, we conclude that the cell wall and/or cell wall-plasma membrane interaction mediated by the integrin-like protein plays important roles in osmotic stress-induced ABA biosynthesis in Zea mays.

Systemic analysis of the differential gene expression profile in a colonic adenoma-normal SSH library

BACKGROUND

The discovery of differentially expressed genes of colonic adenoma minus normal mucosa enables the understanding of early molecular events in colorectal carcinogenesis. In our previous study, we have developed an adenoma minus normal mucosa suppression subtractive hybridization (SSH) library and identified 109 differentially expressed clones.

METHODS

An in-house EST pipeline and the Gene Ontology web-based tool () were used to analyze these clones. Realtime quantitative RT-PCR (Q-PCR) was applied to detect the expression of 14-3-3 zeta, REG4 and 6 ribosomal protein genes (RPS2, RPS12, RPS27A, RPL5, RPL7a and RPL10a) in 14 adenomas (8 with concurrent cancers) and 44 colorectal adenocarcinomas with paired normal mucosa.

RESULTS

Sixty-two candidate genes were obtained from this library. Bioinformatics analysis indicated that both ribosomal protein genes and immune-related genes were enriched. REG4 was significantly upregulated in colorectal adenomas (medium fold: 1.676, p<0.05, Wilcoxon test) and 14-3-3 zeta in cancers (medium fold: 1.202, p<0.01, Wilcoxon test), as compared with those of paired normal mucosa. However, all ribosomal protein genes were not significantly overexpressed in colorectal adenomas or cancers.

CONCLUSIONS

A differential gene expression profile in A-N SSH library may be helpful in understanding the molecular mechanism of colorectal cancer initiation and progression. REG4 and 14-3-3 zeta may be potential biomarkers for early colorectal cancer detection.

Secretagogin, a novel neuroendocrine marker, has a distinct expression pattern from chromogranin A

Preliminary data suggest that secretagogin (SCGN), a calcium-binding protein identified from our previous proteomics study of colorectal cancers, is a potentially useful neuroendocrine marker. In this study, we further analyzed SCGN expression in normal and tumor tissues from various organ sites compared with three other conventional neuroendocrine markers [chromogranin A (CgA), neuron specific enolase, and synaptophysin]. We found strong SCGN staining in most normal neuroendocrine tissues except in the adrenal cortex. SCGN expression was identified in 140 out of 213 neuroendocrine tumors and 12 conventional carcinomas with neuroendocrine differentiation. In a subset of neuroendocrine tumors, such as gastric neuroendocrine cancers and typical carcinoid tumors of rectum and ovary, SCGN showed strong staining while CgA expression was often negative. It is intriguing to note that SCGN staining was positive in 26 out of 31 small cell lung cancers, more frequently than the other three markers. We conclude that SCGN is a novel neuroendocrine marker that may be useful in routine surgical pathology practice.

A transcriptome anatomy of human colorectal cancers

Background

Accumulating databases in human genome research have enabled integrated genome-wide study on complicated diseases such as cancers. A practical approach is to mine a global transcriptome profile of disease from public database. New concepts of these diseases might emerge by landscaping this profile.

Methods

In this study, we clustered human colorectal normal mucosa (N), inflammatory bowel disease (IBD), adenoma (A) and cancer (T) related expression sequence tags (EST) into UniGenes via an in-house GetUni software package and analyzed the transcriptome overview of these libraries by GOTree Machine (GOTM). Additionally, we downloaded UniGene based cDNA libraries of colon and analyzed them by Xprofiler to cross validate the efficiency of GetUni. Semi-quantitative RT-PCR was used to validate the expression of β-catenin and. 7 novel genes in colorectal cancers.

Results

The efficiency of GetUni was successfully validated by Xprofiler and RT-PCR. Genes in library N, IBD and A were all found in library T. A total of 14,879 genes were identified with 2,355 of them having at least 2 transcripts. Differences in gene enrichment among these libraries were statistically significant in 50 signal transduction pathways and Pfam protein domains by GOTM analysis P < 0.01 Hypergeometric Test). Genes in two metabolic pathways, ribosome and glycolysis, were more enriched in the expression profiles of A and IBD than in N and T. Seven transmembrane receptor superfamily genes were typically abundant in cancers.

Conclusion

Colorectal cancers are genetically heterogeneous. Transcription variants are common in them. Aberrations of ribosome and glycolysis pathway might be early indicators of precursor lesions in colon cancers. The electronic gene expression profile could be used to highlight the integral molecular events in colorectal cancers.

[Relationship between the effect of carbamazepine on SCE frequencies and folic acid in epileptic patients]

Peripheral blood lymphocyte sister chromatid exchange(SCE) frequencies, serum folic acid(FA) levels were examined in 15 epileptic patients treated with carbamazepine(CBZ), and another 15 epileptic patients treated with CBZ and folic acid(FA). The untreated epileptic patients and the healthy subjects served as control. The results showed that SCE frequencies were significantly higher in CBZ Group, compared with CBZ plus FA Group and control(P < 0.01). Serum FA levels were lower in CBZ Group compared with healthy control(P < 0.01). It suggests that CBZ can induce the increase of SCE frequencies. Supplementation with FA may effectively prevent chromosome DNA damage induced by CBZ.

Focal shifts in focused nonuniformly polarized beams

We present a simple formula to evaluate the relative focal shift in a circular-aperture lens system illuminated by a nonuniformly polarized (NUP) light wave. Specifically, it is shown that the relative focal shift is determined by the effective Fresnel number. The effective Fresnel number is equal to the product of the Fresnel number of the lens aperture and the parameter sigma, which describes the uniformity of the polarization distribution of the NUP beam across the lens aperture. Some examples are given to illustrate the use of this approach. The influence of the polarization distribution of the incident NUP light wave on the polarization distribution in the axial points of the focused field is also presented.

Generalized M2 factor of hard-edged diffracted flattened Gaussian beams

On the basis of generalized truncated second-order moments, a closed-form expression for the generalized M2 factor of hard-edge diffracted flattened Gaussian beams is derived that is determined by the beam order and the truncation parameter. Special cases are discussed. Moreover, it is shown that the M2 factor of truncated plane waves is equal to 4sqaure root3/3, independent of the aperture width.

[Transition of dietary pattern in China]

The implications of dietary transition in China during the past 50 years were investigated. Data were collected from the representative national surveys, China Health and Nutrition Survey (1989-1997), China National Nutrition Survey (1982 and 1992), the Annual Household Consumption Surveys of the State Statistic Bureau and the Annual Death Report of China. In the early part of the major economic transformation, cereal intake increased before 1985 and decreased thereafter. There was also a long-term reduction of vegetable consumption, which has stabilized now. Intakes of animal foods increased slowly before 1979 and more quickly after the economic reforms occurred. The total energy intake has reduced, as energy expenditure has, large changes in the composition of energy have occurred. The proportion of energy from fat increased quickly and reached 27.3% in average and 32.8% in urban residents in 1997. More than one third of all Chinese adults and 58.4% of adults in urban areas consuming over 30% of their energy from fat. These changes resulted in rapid increases the prevalence of overweight and obesity and dietary-related chronic non-communicable diseases in urban residents. The traditional Chinese diet is shifting towards a diet with high fat, high energy density and low dietary fiber. The Chinese diets have entered into a new stage of transition.

[The effect of epidermal growth factor on the pathologic changes of gastric mucosa in SD rats with chronic atrophic gastritis]

OBJECTIVE

To study the effect of epidermal growth factor (EGF) on the pathologic changes of gastric mucosa in rats with chronic atrophic gastritis(CAG).

METHODS

The established rat models of CAG were divided into therapy group and control group. The rats in the therapy group received EGF 10 microg/kg subcutaneously (SC), whereas these in the control group the same volume of normal saline SC. 12 weeks later, all rats were killed by cervical dislocation and their gastric mucosa were examined with microscope.

RESULTS

The grade of inflammatory cell infiltration in the therapy group was lower than that in the control group (P < 0.01). The thickness of gastric mucosal gland layer was (215.0 +/- 20.7) microm in the therapy group and (139.2 +/- 13.8) microm in the control group (P < 0.01). The ratio of the thickness of gastric mucosal glands and muscularis mucosa(L(1)/L(2)) was 2.70 +/- 0.34 in the therapy group and 1.27 +/- 0.27 in the control group (P < 0.01). The number of gastric glands in 1 mm length of mucosal layer was 26.20 +/- 1.27 in the therapy group and 19.90 +/- 1.78 in the control group (P < 0.01). In the therapy group, the gastric glands were rearranged in order, without signs of malignant proliferation. The width of the expression of proliferating cell nuclear antigen (PCNA ) of gastric mucosa was higher in the therapy group than in the control group [(77.70 +/- 4.16) microm vs (54.40 +/- 4.54) microm, P < 0.01].

CONCLUSIONS

EGF played a therapeutic role in reversing the gastric mucosal atrophy of the rats with CAG. It promoted the expression of PCNA, which induced a protective proliferation of the gastric mucosal lesions in the rats with CAG.

[Construction of luciferase reporter plasmid which is under the control of dioxin-responsive enhancers]

To improve the bio-detection of dioxin-type chemicals, we constructed a plasmid containing reporter under the control of dioxin-responsive enhancer. After connected the enhancer from the plasmid pHAV with the MMTV promoter of the plasmid pCatM, the connected segment was linked with the luciferase vector. Then the recombinant plasmid was transfected to the HepG2 human hepatoma cell line, and the luciferase activity was induced by 2,3,7,8-TCDD. The result suggested that expression of the recombinant luciferase was controlled by the dioxin-responsive enhancer, and there were a linear relationship between the activity of luciferase and certain range of 2,3,7,8-TCDD concentration. It is promising that the transfected cell line could be used for rapid screen and semi quantitation of dioxin-type chemicals, and a standard and routine method for the detection of dioxin-type chemicals by this recombinant plasmid is being under way.

Beam propagation properties of radial laser arrays

A detailed study of phase-locked and non-phase-locked radial laser arrays is presented. The closed-form propagation expressions for the beamlets and the resulting beam are given, which enable us to study beam propagation properties of radial laser arrays for both phase-locked and non-phase-locked cases. Numerical calculation examples are given to illustrate the application of our analytical results and the differences between phase-locked and non-phase-locked radial arrays.

General propagation equation of flattened Gaussian beams

The closed-form propagation equation of flattened Gaussian beams passing through a paraxial optical ABCD system, in which the linear gain and absorption media are included, is derived, and its general applicable advantage is illustrated with numerical examples.

[Rapid rifampicin susceptibility test by using recombinant mycobacteriophages]

OBJECTIVE

To set up a fast, sensitive and specific way to detect mycobacteria and rifampicin susceptibility to mycobacteria by using recombinant mycobacteriophages and bioluminescent method.

METHODS

Firstly detected the luciferase activity in different bacteria by using mycobacteriophages, then assessed the best drug concentration of rifampicin for drug susceptibility test in luciferase reporter assay, and lastly used the above conditions to decide rifampicin susceptibilities to different mycobacteria and compare the result with L-J medium culture.

RESULTS

Bacteriophages had high light production specifically in mycobacteria and only very low light production in E. coli, the difference being obvious. The light production of rifampicin-resisitant mycobacterium strains was much higher than that of sensitive strains in culture with rifampicin(P < 0.05). Different drug concentrations of rifampicin were used to optimize drug concentration for rifampicin drug susceptibility test and the optimum concentration was found to be 2 micrograms/ml. The correlation of drug susceptibility test between luciferase reporter phages to L-J medium in standard strains and clinical isolates was the sarce. Temperature sensitive Phage 88 was more sensitive than Phage 40(P < 0.05). The time for drug resistance test was 72 hours.

CONCLUSIONS

Luciferase reporter phage can detect mycobacteria specifically and can be used in rifampicin susceptibility test. This assay is a fast, sensitive and specific method to detect mycobacterium strains and their resistance to rifampicin.

Coherent and incoherent off-axis Hermite-Gaussian beam combinations

A detailed study of the coherent and the incoherent combinations of two-dimensional off-axis Hermite-Gaussian beams with rectangular symmetry is made. The closed-form propagation formulas of the resulting beam are derived, and the resulting beam quality in terms of the M(2) factor and power in the bucket is discussed and compared for the coherent and the incoherent combinations. In addition, it is shown that the resulting astigmatic beam can be symmetrized in the sense of the second-moment definition of beam width. However, the symmetrizing transformation of the resulting astigmatic beams is incomplete, because there exist different irradiance profiles.

Far-field intensity distribution, M2 factor, and propagation of flattened Gaussian beams

Explicit expressions for the M(2) factor and field distribution of flattened Gaussian beams that propagate through an unapertured paraxial ABCD system are derived and illustrated with numerical examples. We show that the far-field expression of flattened Gaussian beams can be readily obtained by use of our results.

Beam-propagation factor and mode-coherence coefficients of hyperbolic-cosine Gaussian beams

Analytical expressions for the M(2) factor and the mode-coherence coefficients of hyperbolic-cosine- (cosh-) Gaussian beams have been derived, and a simple method of producing cosh-Gaussian beams in an experiment, superposition of two decentered Gaussian beams, has been proposed. Our results will be useful for studying more-general Hermite-sinusoidal-Gaussian beams.

[Impact of maternal occupation on the dietary and nutritional status of preschool children. A case study in 8 provinces of China]

This analysis is based on the data from China Health and Nutrition Survey (undertaken in 8 provinces of China from 1989 to 1998) in collaboration with the University of North Carolina at Chapel Hill. Totally, 1461 and 1087 mother-child pairs under age 6 were selected to investigate the impact of maternal occupation on the dietary and nutritional status of children in 1991 and 1993. The results show that the nutrients intake and nutritional status of children whose mothers worked in administrative, scientific, technological and other professional units were better than any other groups. The status of children whose mothers were workers, waiters etc. in factories or service sectors was better than that of children whose mothers were farmers or self-employed laborers. The children of non-working mothers were better nourished than the children whose mothers were farmers, or self-employed laborers, but were more undernourished than the children whose mothers worked in administrative, scientific, technological and other professional units. The associations among maternal occupation, income and education level of mothers were significant. Mothers working in administrative, scientific, technological units etc. had higher yearly income and education level than other groups. But the income and education level of farmers and self-employed laborers were the lowest. The time allocation of mothers was also studied and the results suggested that maternal occupation affected the time spent for child care and food preparing.

[Study of the plasma adrenomedullin value in pregnancy induced hypertension patients]

OBJECTIVE

To investigate the relationship between adrenomedullin(ADM) and pregnancy induced hypertension(PIH).

METHOD

The ADM values in the plasma from 12 normal term-pregnant women and 26 women with PIH were determined by specific radioimmunoassay.

RESULT

(1) The ADM value in the PIH (24.67 +/- 1.27) ng/L increased significantly than that of normal pregnancy (19.16 +/- 1.17) ng/L (P < 0.05). (2) There were significant difference between severe(30.00 +/- 1.17) ng/L moderate (24.80 +/- 0.70) ng/L and mild (19.38 +/- 2.65) ng/L PIH groups (P < 0.001). (3) Significant positive correlation was found between plasma ADM value and mean arterial pressure (r = 0.775, P < 0.001).

CONCLUSION

The ADM level is closely associated with PIH and may plan an important role in PIH.

[The value of electronystagmography in differential diagnosis of vertigo]

Findings of electronystagmography (ENG) in 645 patients with vertigo were analysed. Two hundred and twelve cases showed vestibular peripheral vertigo, 394 cases vestibular central vestigo, and 39 cases other types of vertigo. The ENGs in patients with vestibular peripheral vertigo were charazterized mainly by the vestibular abnormal caloric responses, spontaneous and benign positional nystagmuses were also obsedrved at the same time. Different degrees and various combinations of the abnormal responses shown in optokinetic central test were the most characteristic of ENG in patients with vestibular central vertigo. The results suggest that ENG is particularly useful for differentiating peripheral and central vertigo.

[The impact of maternal education on the dietary and nutritional status of preschool children--a case study in 8 provinces of China]

This analysis is based on the data from China Health and Nutrition Survey in collaboration with University of North Carolina at Chapel Hill undertaken in 8 provinces of China from 1993 to 1996. Totally, 1098 mother-child pairs under age 6 were investigated. Descriptive analysis and stratified analysis are applied to investigate the impact of maternal education on the dietary and nutritional status of children. Both the crude analysis and after controlling for confounding variables, maternal education in the population remains statistically relevant to children's dietary and nutritional status. The proportion of low body weight and stunting children is the highest in the group with maternal education level being below preliminary school, the lowest in the group with education level being above high middle school. Moreover, in these three groups, the higher the level of maternal education, the greater the percentage of nutrients intake of China RDA, especially those from animal food. These results fully illustrate the importance of maternal education for the prevention of malnutrition in children.

[Impact of maternal income on the nutrients intake of preschool children--a case study in 8 provinces of China]

The data of this study are based on the project "China Health and Nutrition Survey" carried out in 8 provinces of China from 1989 to 1998 in collaboration with the University of North Carolina at Chapel Hill, USA. Totally, 1180 and 916 mother-child pairs aged 2-6 were investigated in 1991 and 1993 respectively. Descriptive and stratified analysis is applied to investigate the impact of maternal income on the nutrients intake of children. It is found that the nutrients intake of children in higher maternal income group is greater than that in lower maternal income group. After adjusting for family income, the results show that the more contribution of the mother's income to the family, the more nutrients intake of their children, especially in lower income families. It is illustrated that the income of mother may be more important for children's dietary status than that of other members of the family.

Three-dimensional reconstruction of electron beam computed tomography angiography for evaluating coronary artery bypass grafts

OBJECTIVES

To probe into electron beam computed tomography (EBCT) angiography and 3-D reconstruction of coronary artery bypass grafts (CABG) and to evaluate the clinical application of EBCT angiography and 3-D reconstruction of CABG.

METHODS

EBCT angiography with 3-D reconstruction was achieved in 150 patients (142 men and 8 women, mean age, 57 +/- 8 years) with 399 grafts including 100 internal mammary artery grafts (IMG), 296 saphenous vein grafts(SVG) and 3 radial artery grafts (RAG) respectively. The time from bypass surgery to EBCT scanning ranged from 7 days to 120 months, averaging 15 +/- 28 months. Enhanced single slice mode (SSM) and flow studies were performed in all patients. The results of 3-D reconstruction of CABG were compared with bypass operation records and with coronary arteriograms (7 patients).

RESULTS

150 patients underwent successfully EBCT angiography and CABG 3-D reconstruction. According to 3-D reconstruction of the coronary bypass grafts with flow studies, 318 of 399 coronary bypass grafts were patent including IMG patency in 87/100 (87%), SVG in 228/296 (77%) and RAG in 3/3 (100/100). The overall patent rate was 79.7%. In 7 patients with 12 coronary bypass grafts, EBCT studies showed graft patency (7 grafts) and occlusion (5), which were confirmed by conventional graft angiography.

CONCLUSIONS

EBCT angiography with 3-D reconstruction is effective in providing the entire anatomic structure of coronary bypass grafts and evaluating coronary bypass graft patency. EBCT flow study can provide quantitative data for evaluating coronary bypass graft patency and for supplemental diagnosis of CABG 3-D reconstruction. EBCT angiography is a noninvasive technique that could replace conventional coronary arteriography for follow-up survey of coronary bypass surgery in future.

Nondegenerate four-wave mixing in a double-Lambda system under the influence of coherent population trapping

Nondegenerate four-wave mixing (NDFWM) in a double-L system of Rb atomic vapor was achieved for collinear pump fields. By comparison of different pump-probe configurations, direct experimental evidence of influence of coherent population trapping on the output power of the NDFWM signal was established. A maximal efficiency for generating the NDFWM signal exists for a moderate pump power in this double-L system.

[RU486 reverses dexamethasone-mediated suppression of IL-2 receptor expressions in lymphocytes of rat spleen]

Experiments were designed to investigate whether glucocorticoid-mediated immunosuppression are involved in glucocorticoid receptor activation. It was shown that RU486, a blocker of glucocorticoid, reversed dexamethasone (DEX)-mediated suppression of CD25 antigen expressions on ConA-stimulated lymphocytes, as determined with anti-CD25 monoclonal antibody. By means of radioligand binding assay, changes in high affinity IL-2 receptor were examined. The data indicated that RU486 alone was unable to affect high affinity IL-2 receptor expressions, but antagonized DEX-mediated down regulation of high affinity IL-2 receptor on cellular surface. The maximal binding capacities of IL-receptor were 10.0 +/- 0.7, 10.4 +/- 2.1, 6.5 +/- 0.8 and 12.1 +/- 2.7 fmol/10(7) cell respectively in four groups of the normal, RU486, DEX, and DEX plus RU486. The results suggest that such effects of DEX may be mediated through glucocorticoid receptor in lymphocytes.

[Clarithromycin combined short-term triple therapies for eradication of Helicobacter pylori infection]

In order to explore the optimal regimens for the eradication of Helicobacter pylori (Hp), eighty-eight patients with duodenal ulcer (DU) or non-ulcer dyspepsia and Hp infection, defined by culture and histology, received the one-week triple therapy with clarithromycin (Cla), furazolidone (Fur) plus lansoprazole (Lan) or colloidal bismuth subcitrate (CBS). Twenty-eight patients entered the phase one preliminary study, randomized to receive the treatment of Cla 500 mg b.i.d and Fur 200 mg b.i.d plus either CBS 240 mg b.i.d (group I A) or Lan 30 mg b.i.d (group I B). Sixty patients entered the phase two main study, receiving the treatment of Cla 250 mg b.i.d and Fur 100 mg b.i.d plus either CBS 240 mg b.i.d (group II A) or Lan 30 mg q.d (group II B). Five patients (2 in group I A, 2 in group I B, 1 in group II A) were withdrawn because of the side effects of the treatment, and two (in group II A) dropped out. The eradication rates of Hp in group I A, I B, II A, II B were 100.0% (12/12), 91.7% (11/12), 92.6% (25/27) and 90.0% (27/30) respectively. There was no significant difference in the eradication rates of Hp between the treatment groups (P > 0.05). The primary resistant rate of Hp isolates to Cla was 7.5% (4/53) and no patient infected with the strain resistant to Cla succeeded in the eradication of Hp. The healing rates of DU were 94.4% (17/18) in group II A and 100.0% (18/18) in group II B (P > 0.05). The main side effects were nausea, vomiting and taste disturbance. Eighteen of the 28 (64.2%) patients in the phase one study had side effects with a rate significantly higher than that of 5.1% (3/58) in the phase two study (P < 0.001).

CONCLUSIONS

(1) Both of the regimens used in the phase two study with low-dose, one week triple therapy are highly effective in the eradication of Hp infection and healing of DU, and are well tolerated. (2) The primary resistance of Hp strains to Cla is the principal factor of treatment failure in these two regimens.

[Determination of trace arsenic in soy and vinegar by catalytic oscillopolarography]

The determination of trace arsenic in soy and vinegar by oscillopolarography was investigated. A sensitive catalytic wave of arsenic appeared at -0.73V (vs. SCE) in 2mol/L H2SO4-0.2 mol/L KI-5 micrograms/ml Te systems. The linear relationship was 0-100ppb. The determination of arsenic in soy and vinegar was carried out after digestion with nitricperchloric acids. The detection limit was 1 ppb. The relative standard deviations were 4.7% and 8.8% respectively from the determinations of soy and vinegar. Recoveries were 92%-102% and 96%-110% respectively.