A predicted-loss based active learning approach for robust cancer pathology image analysis in the workplace

BACKGROUND

Convolutional neural network-based image processing research is actively being conducted for pathology image analysis. As a convolutional neural network model requires a large amount of image data for training, active learning (AL) has been developed to produce efficient learning with a small amount of training data. However, existing studies have not specifically considered the characteristics of pathological data collected from the workplace. For various reasons, noisy patches can be selected instead of clean patches during AL, thereby reducing its efficiency. This study proposes an effective AL method for cancer pathology that works robustly on noisy datasets.

METHODS

Our proposed method to develop a robust AL approach for noisy histopathology datasets consists of the following three steps: 1) training a loss prediction module, 2) collecting predicted loss values, and 3) sampling data for labeling. This proposed method calculates the amount of information in unlabeled data as predicted loss values and removes noisy data based on predicted loss values to reduce the rate at which noisy data are selected from the unlabeled dataset. We identified a suitable threshold for optimizing the efficiency of AL through sensitivity analysis.

RESULTS

We compared the results obtained with the identified threshold with those of existing representative AL methods. In the final iteration, the proposed method achieved a performance of 91.7% on the noisy dataset and 92.4% on the clean dataset, resulting in a performance reduction of less than 1%. Concomitantly, the noise selection ratio averaged only 2.93% on each iteration.

CONCLUSIONS

The proposed AL method showed robust performance on datasets containing noisy data by avoiding data selection in predictive loss intervals where noisy data are likely to be distributed. The proposed method contributes to medical image analysis by screening data and producing a robust and effective classification model tailored for cancer pathology image processing in the workplace.

Improving quality control in the routine practice for histopathological interpretation of gastrointestinal endoscopic biopsies using artificial intelligence

BACKGROUND

Colorectal and gastric cancer are major causes of cancer-related deaths. In Korea, gastrointestinal (GI) endoscopic biopsy specimens account for a high percentage of histopathologic examinations. Lack of a sufficient pathologist workforce can cause an increase in human errors, threatening patient safety. Therefore, we developed a digital pathology total solution combining artificial intelligence (AI) classifier models and pathology laboratory information system for GI endoscopic biopsy specimens to establish a post-analytic daily fast quality control (QC) system, which was applied in clinical practice for a 3-month trial run by four pathologists.

METHODS AND FINDINGS

Our whole slide image (WSI) classification framework comprised patch-generator, patch-level classifier, and WSI-level classifier. The classifiers were both based on DenseNet (Dense Convolutional Network). In laboratory tests, the WSI classifier achieved accuracy rates of 95.8% and 96.0% in classifying histopathological WSIs of colorectal and gastric endoscopic biopsy specimens, respectively, into three classes (Negative for dysplasia, Dysplasia, and Malignant). Classification by pathologic diagnosis and AI prediction were compared and daily reviews were conducted, focusing on discordant cases for early detection of potential human errors by the pathologists, allowing immediate correction, before the pathology report error is conveyed to the patients. During the 3-month AI-assisted daily QC trial run period, approximately 7-10 times the number of slides compared to that in the conventional monthly QC (33 months) were reviewed by pathologists; nearly 100% of GI endoscopy biopsy slides were double-checked by the AI models. Further, approximately 17-30 times the number of potential human errors were detected within an average of 1.2 days.

CONCLUSIONS

The AI-assisted daily QC system that we developed and established demonstrated notable improvements in QC, in quantitative, qualitative, and time utility aspects. Ultimately, we developed an independent AI-assisted post-analytic daily fast QC system that was clinically applicable and influential, which could enhance patient safety.

MixPatch: A New Method for Training Histopathology Image Classifiers

CNN-based image processing has been actively applied to histopathological analysis to detect and classify cancerous tumors automatically. However, CNN-based classifiers generally predict a label with overconfidence, which becomes a serious problem in the medical domain. The objective of this study is to propose a new training method, called MixPatch, designed to improve a CNN-based classifier by specifically addressing the prediction uncertainty problem and examine its effectiveness in improving diagnosis performance in the context of histopathological image analysis. MixPatch generates and uses a new sub-training dataset, which consists of mixed-patches and their predefined ground-truth labels, for every single mini-batch. Mixed-patches are generated using a small size of clean patches confirmed by pathologists while their ground-truth labels are defined using a proportion-based soft labeling method. Our results obtained using a large histopathological image dataset shows that the proposed method performs better and alleviates overconfidence more effectively than any other method examined in the study. More specifically, our model showed 97.06% accuracy, an increase of 1.6% to 12.18%, while achieving 0.76% of expected calibration error, a decrease of 0.6% to 6.3%, over the other models. By specifically considering the mixed-region variation characteristics of histopathology images, MixPatch augments the extant mixed image methods for medical image analysis in which prediction uncertainty is a crucial issue. The proposed method provides a new way to systematically alleviate the overconfidence problem of CNN-based classifiers and improve their prediction accuracy, contributing toward more calibrated and reliable histopathology image analysis.

A loss-based patch label denoising method for improving whole-slide image analysis using a convolutional neural network

This paper proposes a deep learning-based patch label denoising method (LossDiff) for improving the classification of whole-slide images of cancer using a convolutional neural network (CNN). Automated whole-slide image classification is often challenging, requiring a large amount of labeled data. Pathologists annotate the region of interest by marking malignant areas, which pose a high risk of introducing patch-based label noise by involving benign regions that are typically small in size within the malignant annotations, resulting in low classification accuracy with many Type-II errors. To overcome this critical problem, this paper presents a simple yet effective method for noisy patch classification. The proposed method, validated using stomach cancer images, provides a significant improvement compared to other existing methods in patch-based cancer classification, with accuracies of 98.81%, 97.30% and 89.47% for binary, ternary, and quaternary classes, respectively. Moreover, we conduct several experiments at different noise levels using a publicly available dataset to further demonstrate the robustness of the proposed method. Given the high cost of producing explicit annotations for whole-slide images and the unavoidable error-prone nature of the human annotation of medical images, the proposed method has practical implications for whole-slide image annotation and automated cancer diagnosis.

Methanolic extract of Kigelia africana exhibits antiatherosclerotic effects in endothelial cells by downregulating RAGE and adhesion molecules

The Kigelia plant is used in African countries for its medicinal properties. Kigelia africana is an interesting example of a medicinal plant due to its pharmacological activities, including its anti-inflammatory effect. Atherosclerosis, the primary cause of cardiovascular disease, is related to lipoprotein oxidation, inflammation and immune responses involving the vascular endothelium and immune cells. Therefore, in this study we investigated the effects of Kigelia africana (Lam.) extract, focusing particularly on antiatherosclerotic effects in endothelial cells (ECs). The methanolic extract of Kigelia africana (MKA) showed no cytotoxicity on ECs at doses of 10~200 µg/ml. MKA reduced RAGE expression on oxLDL- or TNF-α-stimulated ECs in a dose dependent manner, showing significant inhibition at a concentration of 50 µg/ml. In addition, MKA significantly inhibited the oxLDL- or TNF-αinduced expression of vascular cell adhesion molecule-1 (VCAM-1) in ECs in a dose-dependent manner but did not affect intracellular adhesion molecule-1 (ICAM-1), resulting in downregulation of the migration and adhesion of THP-1 monocytes to ECs. These results suggest that MKA could be used for the treatment of atherosclerosis without cytotoxicity.

Diagnostic Limitation of Fine-Needle Aspiration (FNA) on Indeterminate Thyroid Nodules Can Be Partially Overcome by Preoperative Molecular Analysis: Assessment of RET/PTC1 Rearrangement in BRAF and RAS Wild-Type Routine Air-Dried FNA Specimens

Molecular markers are helpful diagnostic tools, particularly for cytologically indeterminate thyroid nodules. Preoperative RET/PTC1 rearrangement analysis in BRAF and RAS wild-type indeterminate thyroid nodules would permit the formulation of an unambiguous surgical plan. Cycle threshold values according to the cell count for detection of the RET/PTC1 rearrangement by real-time reverse transcription-polymerase chain reaction (RT-PCR) using fresh and routine air-dried TPC1 cells were evaluated. The correlation of RET/PTC1 rearrangement between fine-needle aspiration (FNA) and paired formalin-fixed paraffin-embedded (FFPE) specimens was analyzed. RET/PTC1 rearrangements of 76 resected BRAF and RAS wild-type classical PTCs were also analyzed. Results of RT-PCR and the Nanostring were compared. When 100 fresh and air-dried TPC1 cells were used, expression of RET/PTC1 rearrangement was detectable after 35 and 33 PCR cycles, respectively. The results of RET/PTC1 rearrangement in 10 FNA and paired FFPE papillary thyroid carcinoma (PTC) specimens showed complete correlation. Twenty-nine (38.2%) of 76 BRAF and RAS wild-type classical PTCs had RET/PTC1 rearrangement. Comparison of RET/PTC1 rearrangement analysis between RT-PCR and the Nanostring showed moderate agreement with a κ value of 0.56 (p = 0.002). The RET/PTC1 rearrangement analysis by RT-PCR using routine air-dried FNA specimen was confirmed to be technically applicable. A significant proportion (38.2%) of the BRAF and RAS wild-type PTCs harbored RET/PTC1 rearrangements.

Cytomorphological findings and histological correlation of low-grade cribriform cystadenocarcinoma of salivary gland in fine-needle aspiration: a case study

Low-grade cribriform cystadenocarcinoma (LGCCC) of the salivary gland is a rare tumor. We report the cytologic features and histologic correlation of a patient with LGCCC. A 57-year-old man had a hardly palpable, nontender mass in the right cheek area followed over nine months. Radiologic analysis revealed a 1.2 cm multiseptated, cystic, solid nodule in an anterior superficial lobe of the right parotid gland. Fine-needle aspiration cytology revealed many irregular overlapping sheets or clusters of ductal epithelial cells forming solid, pseudopapillary, and cribriform architectures. Nuclei of the tumor cells revealed inconspicuous atypia with minimal size variation. On the basis of these findings, we confirmed a diagnosis of ductal epithelial proliferative lesion, favoring neoplasm, with uncertain malignant potential. Tumor excision was performed, revealing a tiny multicystic nodule (0.7 cm). Histopathologically, this tumor showed the characteristic morphology of LGCCC. This is the first report of cytomorphological findings of LGCCC in Korea.

A Case of Multifocal Papillary Thyroid Carcinoma Consisting of One Encapsulated Follicular Variant with BRAF K601E Mutation and Three Conventional Types with BRAF V600E Mutation

Multifocal papillary thyroid carcinoma (mPTC) comprises about 20-30% of PTC. In mPTC, individual tumor foci can be identical or frequently composed of different histological types including follicular, solid, tall-cell or conventional patterns. We report a case of mPTC consisting of one encapsulated follicular variant of papillary thyroid carcinoma (FVPTC) and three conventional PTCs in a 44-year-old woman. This case genetically demonstrates unique features including the simultaneous presence of the BRAF V600E (T1799A) mutation and the BRAF K601E (A1801G) mutation in conventional PTC and FVPTC, respectively.

Primary pure squamous cell carcinoma of the thyroid: report and histogenic consideration of a case involving a BRAF mutation

Primary squamous cell carcinoma of the thyroid (SCC-T) is extremely rare. Its clinical presentation is similar to that of anaplastic carcinoma. Metastasis or extension from the head and neck area should be ruled out, as patients with SCC-T have a poorer prognosis than patients who have a thyroid extension from an adjacent tumor. An 87-year-old man presented with a longstanding painless mass in the right thyroid and had experienced 2 months of pain upon swallowing. A right lobectomy was performed with resection of thyroid cartilage, cricoid cartilage, a portion of the first to third tracheal ring and the right neck lymph node. A histological examination revealed pure SCC. The tumor cells showed diffuse immunoreactivity to CK5/6, CK19 and p63. Immunoreactivity to EMA and p53 was focally positive. TTF-1, galectin 3 and thyroglobulin immunoreactivity was restricted to the non-neoplastic thyroid tissue. Both tumor cells and non-neoplastic follicular cells were negative for CD5. The MIB-1 index was 36%. DNA extracted from the tumor identified a BRAF V600E mutation in exon 15 and a BRAF G468A mutation in exon 11, whereas DNA from non-tumorous cells did not contain a mutation. These molecular findings may suggest a direct transformation from papillary carcinoma to SCC-T.

Therapy-related acute leukemia with mixed phenotype and t(9;22)(q32;q11.2): a case report and review of the literature

Therapy-related acute leukemia showing mixed phenotype is extremely rare. We report a 49-year-old woman who presented with palpable masses in her neck and back. She had received systemic chemotherapy (adriamycin and cisplatin) and radiotherapy for endometrial adenocarcinoma 7 years before. Her peripheral blood and bone marrow showed increased blasts, which coexpressed myeloid (CD13, CD33, and myeloperoxidase) and B-lymphoid antigens (CD19 and CD79a). Cytogenetic analysis showed a karyotype of 46,XX,dup(1)(q21q32),add(5)(q33),t(9;22)(q34;q11.2)[12]/47,idem,+der(22)t(9;22)[8], and BCR/ABL1 rearrangement was detected. Leukemic infiltration was also confirmed in her back mass. After induction chemotherapy with idarubicin, cytarabine, and imatinib, she achieved complete remission. Only 2 cases of therapy-related acute leukemia with mixed phenotype have been reported so far: one with hyperploidy and the other with t(1;21)(p36;q22). To the best of our knowledge, this is the first case of therapy-related acute leukemia with mixed phenotype and t(9;22) as well as extramedullary leukemic infiltrations.

A hypoxia-dependent upregulation of hypoxia-inducible factor-1 by nuclear factor-κB promotes gastric tumour growth and angiogenesis

BACKGROUND

The underlying mechanisms involved in the activation of hypoxia-inducible factor-1 (HIF-1) in gastric cancer remain unclear. As nuclear factor-κB (NF-κB) as well as HIF-1 have been implicated in angiogenesis of various cancers, we investigated their relationship in gastric cancer.

METHODS

Nuclear expressions of HIF-1α and NF-κB/RelA were assessed in 251 human gastric carcinoma specimens by immunohistochemical tissue array analysis. Stable human gastric cancer cells, infected with a retroviral vector containing super-suppressive mutant form of IκBα (IκBαM), were used for animal studies as well as cell culture experiments. Xenografted tumours were measured and IκBαM effects on angiogenesis and HIF-1α activation were assessed by immunohistochemistry, western blotting, luciferase reporter assay, and semiquantitative reverse transcription-polymerase chain reaction. In addition, NF-κB effects on the HIF-1α degradation and synthesis were examined.

RESULTS

Hypoxia-inducible factor-1α activation positively correlated with RelA activation in clinical gastric cancer samples (P<0.001). The IκBαM overexpression suppressed tumour growth, microvessel density, and HIF-1α activation in xenografted tumours. Cell culture experiments showed that hypoxia-induced HIF-1α expression was reduced by NF-κB inhibition under hypoxic conditions at the translational level.

CONCLUSION

The hypoxia-dependent activation of the NF-κB/HIF-1α/VEGF pathway contributes, at least in part, to gastric cancer promotion via enhancement of angiogenesis.

Fluoroscopy and sonographic guided injection of obliquus capitis inferior muscle in an intractable occipital neuralgia

Occipital neuralgia is a form of headache that involves the posterior occiput in the greater or lesser occipital nerve distribution. Pain can be severe and persistent with conservative treatment. We present a case of intractable occipital neuralgia that conventional therapeutic modalities failed to ameliorate. We speculate that, in this case, the cause of headache could be the greater occipital nerve entrapment by the obliquus capitis inferior muscle. After steroid and local anesthetic injection into obliquus capitis inferior muscles under fluoroscopic and sonographic guidance, the visual analogue scale was decreased from 9-10/10 to 1-2/10 for 2-3 weeks. The patient eventually got both greater occipital neurectomy and partial resection of obliquus capitis inferior muscles due to the short term effect of the injection. The successful steroid and local anesthetic injection for this occipital neuralgia shows that the refractory headache was caused by entrapment of greater occipital nerves by obliquus capitis inferior muscles.

Dietary taurine intake and serum taurine levels of women on Jeju Island

The purpose of this study was to investigate the dietary taurine intake and serum taurine levels of women on Jeju Island in Korea. Sixty six married women aged 43.5 +/- 7.1 volunteered for this study: 34 from the city area and 32 from two fishing-farming areas. Diet samples were collected from the participants; the samples included three meals (breakfast, lunch and supper), including snacks, drinks and whatever else the participants had eaten for 24 hours. Taurine levels in the diet and serum were determined as the dabsyl derivative by HPLC with a Rf-detector. The intake of taurine ranged from 8.4 to 767.6 mg/day and its mean value was 163.9 +/- 150.2 mg/day (mean +/- SD). There was a significant difference between the two groups: 114.9 +/- 78.7 for the women from the city area and 215.9 +/- 187.9 mg/day for the women from the fishing-farming areas (p<0.001). The taurine intake of the total diet, including all snacks and drinks, was 2300 +/- 584 g/day for the city area and 2342 +/- 528 g/day for the fishing-farming areas. The daily protein intake was 58.8 +/- 16.4 g for the women of the city area and 65.5 +/- 17.1 g for the women of the fishing-farming areas. There was a significant correlation between the intake of fish/shellfish and taurine (p=0.001) while there was no correlation between the intake of protein and taurine (p=0.057). The taurine levels in serum ranged from 68.6 to 261.6 micromol/L and the mean value was 169.7 +/- 41.5 micromol/L. There was no significant difference between the women from the city area and the women from the fishing-farming areas in serum taurine levels. The correlations of serum taurine levels with serum retinol levels (p=0.016) and alpha-tocopherol (p=0.014) levels were significant. These results suggest that taurine intake is dependent on the fish/shellfish intake and that taurine may play an important role in the retention of antioxidative nutrients.

Effects of ginsenosides on vanilloid receptor (VR1) channels expressed in Xenopus oocytes

Ginsenosides, or ginseng saponins, are biologically active ingredients of Panax ginseng. Accumulating evidence suggests that ginsenosides can alleviate pain from injections of noxious chemicals, such as capsaicin [Nah et al. (2000)]. In this study we examined the effects of ginsenoside Rc on the capsaicin-induced inward current in Xenopus oocytes that expresses the vanilloid receptor 1 (VR1). Ginsenoside Rc enhanced the capsaicin-induced inward current in a concentration-dependent and reversible manner, but ginsenoside Rc itself elicited no membrane currents. The VR1 antagonist capsazepine almost completely blocked the inward current that was elicited by capsaicin plus ginsenoside Rc. We also tested the effect of seven other fractionated ginsenosides (i.e., Rb1, Rb2, Rd, Re, Rf, Rg1, and Rg2) in addition to ginsenoside Rc. We found that six of them significantly enhanced the inward current that is induced by capsaicin with the following order of potency: Rc > Rf > Rg1 approximately Rd > Rb2 > Rb1. These results show the possibility that the in vivo effect of ginsenosides against capsaicin-induced pain is derived from their modulation of the VR1 channel function.

G alpha(q/11) coupled to mammalian phospholipase C beta 3-like enzyme mediates the ginsenoside effect on Ca(2+)-activated Cl(-) current in the Xenopus oocyte

Recently we demonstrated that ginsenosides, the active ingredients of Panax ginseng, enhanced Ca(2+)-activated Cl(-) current in the Xenopus oocyte through a signal transduction mechanism involving the activation of pertussis toxin-insensitive G protein and phospholipase C (PLC). However, it has not yet been determined precisely which G protein subunit(s) and which PLC isoform(s) participate in the ginsenoside signaling. To provide answers to these questions, we investigated the changes in ginsenoside effect on the Cl(-) current after intraoocyte injections of the cRNAs coding various G protein subunits, a regulator of G protein signaling (RGS2), and G beta gamma-binding proteins. In addition, we examined which of mammalian PLC beta 1-3 antibodies injected into the oocyte inhibited the action of ginsenosides on the Cl(-) current. Injection of G alpha(q) or G alpha(11) cRNA increased the basal Cl(-) current recorded 48 h after, and it further prevented ginsenosides from enhancing the Cl(-) current, whereas G alpha(i2) and G alpha(oA) cRNA injection had no significant effect. The changes following G alpha(q) cRNA injection were prevented when G beta(1)gamma(2) and G alpha(q) subunits were co-expressed by simultaneous injection of the cRNAs coding these subunits. Injection of cRNA coding G alpha(q)Q209L, a constitutively active mutant that does not bind to G beta gamma, produced effects similar to those of G alpha(q) cRNA injection. The effects of G alpha(q)Q209L cRNA injection, however, were not prevented by co-injection of G beta(1)gamma(2) cRNA. Injection of the cRNA coding RGS2, which interacts most selectively with G alpha(q/11) among various identified RGS isoforms and stimulates the hydrolysis of GTP to GDP in active GTP-bound G alpha subunit, resulted in a severe attenuation of ginsenoside effect on the Cl(-) current. Finally, antibodies against PLC beta 3, but not -beta 1 and -beta 2, markedly attenuated the ginsenoside effect examined at 3-h postinjection. These results suggest that G alpha(q/11) coupled to mammalian PLC beta 3-like enzyme mediates ginsenoside effect on Ca(2+)-activated Cl(-) current in the Xenopus oocyte.

Heterogeneity of myocardial sleeve morphology and gap junctions in canine superior vena cava

BACKGROUND

The myocardial sleeve of the superior vena cava (SVC) has been identified as a potential initiating focus in atrial fibrillation, but information on cell-to-cell linkage at this site is lacking.

METHODS AND RESULTS

We examined the SVC in 8 dogs by immunoconfocal and electron microscopy. Cardiomyocytes outlined with vinculin and bearing striations positive for alpha-actinin are found in the proximal segment of the SVC. These cells, grouped in bundles of various orientations according to location, extend cephalically as far as 3 cm from the right atrium (RA)-SVC junction. Comparison between the junctional level and the level 2 cm distal shows that the myocardial layer in the latter is thinner and not as compact and is composed of longer cells (87.3+/-15.7 versus 71.6+/-14.4 micrometer, P<0.01). Gap junctions made of connexin43 (Cx43), Cx40, and Cx45 are aggregated mainly at the intercalated disks, and colocalization of connexins is a common feature throughout the myocardial sleeve. Areas of atypical expression exist, however, characterized by a center of abundant Cx43 labels surrounded by a periphery of scattered tiny Cx40-labeled spots. Although in the ventral subluminal compact myocardial layer, individual cells at both levels are surrounded by similar numbers of cells, the number of aggregation of labeled gap junctions at the distal level is less (2.3+/-0.6 versus 3.7+/-0.9, P<0.01). In addition, electron-microscopic examination demonstrates that the gap junctions at the distal level are smaller in size (0.37+/-0.30 versus 0.55+/-0.34 micrometer, P<0.01).

CONCLUSIONS

The myocardial sleeve in the canine SVC is a heterogeneous structure, which could potentially form a substrate for heterogeneity of electrical coupling.

Design and pharmacological activity of phosphinic acid based NAALADase inhibitors

A novel series of phosphinic acid based inhibitors of the neuropeptidase NAALADase are described in this work. This series of compounds is the most potent series of inhibitors of the enzyme described to date. In addition, we have shown that these compounds are protective in animal models of neurodegeneration. Compound 34 significantly prevented neurodegeneration in a middle cerebral artery occlusion model of cerebral ischemia. In addition, in the chronic constrictive model of neuropathic pain, compound 34 significantly attenuated the hypersensitivity observed with saline-treated animals. These data suggest that NAALADase inhibition may provide a new approach for the treatment of both neurodegenerative disorders and peripheral neuropathies.

Bakuchiol: a hepatoprotective compound of Psoralea corylifolia on tacrine-induced cytotoxicity in Hep G2 cells

Bioassay-guided fractionation of the H(2)O extract of the seeds of Psoralea corylifolia furnished one hepatoprotective compound, bakuchiol (1), together with two moderately active compounds, bakuchicin (2) and psoralen (3), on tacrine-induced cytotoxicity in human liver-derived Hep G2 cells. The EC(50) values of compounds 1 - 3 are 1.0, 47.0, 50.0 microg/ml, respectively. Silymarin as a positive control showed the EC(50) value with 5.0 microg/ml.

Lack of association between the Glu298Asp variant of the endothelial nitric oxide synthase gene and the risk of coronary artery disease among Taiwanese

BACKGROUND AND PURPOSE

Endothelial nitric oxide synthase (eNOS) plays a key role in atherosclerosis, because its product, nitric oxide, possesses antiatherogenic properties. Recent reports of molecular genetic analysis have suggested that genetic polymorphisms of the eNOS gene may be associated with coronary artery disease (CAD) or myocardial infarction (MI). However, some studies have reported discrepant results. The aims of this study were to assess whether any association exists between the Glu298Asp variant of the eNOS gene and the risk of CAD and/or MI among Taiwanese.

METHODS

The subjects included 218 CAD patients and the same number of age- and sex-matched control subjects from Taiwan. Subjects' DNA was extracted from their blood and genotypes were determined by polymerase chain reaction and restriction mapping using the restriction enzyme MboI. The alleleic and genotypic frequencies were analyzed.

RESULTS

The frequencies of the eNOS genotypes were similar for CAD patients (GG:GT:TT = 81.7%:17.4%:0.9%) and controls (81.2%:17.4%:1.4%; p = 0.904). No evidence of difference was found in the frequency of the T allele between CAD patients (9.6%) and controls (10.1%; p = 0.822), or between MI patients (7.5%) and controls (p = 0.322). Subjects with the GT or TT genotype did not demonstrate an increased risk of CAD compared with those with a GG genotype (p = 0.89; OR = 0.98; 95% confidence interval, CI, 0.76-1.27) in multivariate logistic regression, or when different subgroups of age, sex, or risk factors were analyzed.

CONCLUSIONS

In the present case-control study, we found no evidence of an association between the Glu298Asp variant of the eNOS gene and CAD/MI among Taiwanese.

Prevalence of hepatitis B and C virus infection among women in Jeju Island, Republic of Korea

Hepatitis B and C virus infection prevalence was investigated in the Island of Jeju (formerly Cheju), the Republic of Korea, by means of a small-scale sero-epidemiological survey in 2000. Adult women in the city of Jeju (the provincial capital) and two fishing-farming villages A and B were invited to offer venous blood samples for immunological examination for infection markers of two virus and serum biochemistry for liver function. In practice, 66 married women (33, 16 and 17 women from the city, Village A and Village B, respectively) volunteered. Sera were separated on site and were assayed for HBsAg, anti-HBs, anti-HBc, and anti-HCV positivities and liver function markers including AST, ALT and gamma-GTP. The serum assay showed that the prevalence of HbsAg+ or anti-HCV+ cases was low (5 and 2%, respectively), whereas that of anti-HBs+ and anti-HBc+ cases were high (71 and 62%) so that the over-all HBV positivity was 82%. There were essentially no urban-rural difference or age-dependent changes in the positivity. Comparison with the prevalence reported in literature shows that prevalence of HBsAg+ and anti-HCV+ is in general agreement with the values reported for the populations in general, but HBV+ prevalence might be somewhat higher than the levels reported for the general populations.

Regional differentiation of desmin, connexin43, and connexin45 expression patterns in rat aortic smooth muscle

The gap-junctional protein, connexin43, is differentially expressed in vascular smooth muscle cells (SMCs) according to phenotype. Previous studies suggest that desmin-negative SMCs are characterized by high levels of connexin43, whereas desmin-positive SMCs (of a more contractile phenotype) typically have low connexin43 levels. In this study, we examine systematically the inverse relationship between connexin43 and desmin in SMCs of defined regions of the rat aortic media and determine whether additional connexin isotypes are expressed and contribute to this relationship. Immunoconfocal microscopy demonstrated that (1) the inverse relationship between connexin43 and desmin expression holds true for the media of sequential aortic zones, with 1 exception, the ascending aorta, and (2) an additional vascular connexin, connexin45, is expressed by aortic SMCs. Examination of connexin43, connexin45, and desmin expression in sequential aortic zones reveals 3 SMC subpopulations. The first, predominating in the aortic arch and thoracic aorta, is desmin negative and contains high connexin43 levels; the second, predominating in the abdominal aorta and iliac artery, is desmin positive and contains low connexin43 levels; and the third, which is restricted to the ascending aorta, is desmin positive and expresses high connexin43 levels. Connexin45 levels are high in the ascending aorta but low in the other aortic segments. In para-aortic veins, a fourth SMC subpopulation appears, one that is desmin positive and contains connexin45 but not connexin43. These results demonstrate that a diversity of connexin expression patterns characterizes distinctive subpopulations of medial SMCs in situ with a potential to contribute to regional differentiation of vascular function.

Immunocytochemical analysis of connexin expression in the healthy and diseased cardiovascular system

Gap junctions play essential roles in the normal function of the heart and arteries, mediating the spread of the electrical impulse that stimulates synchronized contraction of the cardiac chambers, and contributing to co-ordination of activities between cells of the arterial wall. In common with other multicellular systems, cardiovascular tissues express multiple connexin isotypes that confer distinctive channel properties. This review highlights how state-of-the-art immunocytochemical and cellular imaging techniques, as part of a multidisciplinary approach in gap junction research, have advanced our understanding of connexin diversity in cardiovascular cell function in health and disease. In the heart, spatially defined patterns of expression of three connexin isotypes-connexin43, connexin40, and connexin45-underlie the precisely orchestrated patterns of current flow governing the normal cardiac rhythm. Derangement of gap junction organization and/or reduced expression of connexin43 are associated with arrhythmic tendency in the diseased human ventricle, and high levels of connexin40 in the atrium are associated with increased risk of developing atrial fibrillation after coronary by-pass surgery. In the major arteries, endothelial gap junctions may simultaneously express three connexin isotypes, connexin40, connexin37, and connexin43; underlying medial smooth muscle, by contrast, predominantly expresses connexin43, with connexin45 additionally expressed at restricted sites. In normal arterial smooth muscle, the abundance of connexin43 gap junctions varies according to vascular site, and shows an inverse relationship with desmin expression and positive correlation with the quantity of extracellular matrix. Increased connexin43 expression between smooth muscle cells is closely linked to phenotypic transformation in early human coronary atherosclerosis and in the response of the arterial wall to injury. Current evidence thus suggests that gap junctions in both their guises, as pathways for cell-to-cell signaling in the vessel wall and as pathways for impulse conduction in the heart, contribute to the initial pathogenesis and eventual clinical manifestation of human cardiovascular disease.

Age-related alteration of gap junction distribution and connexin expression in rat aortic endothelium

We investigated endothelial gap junctions and their three component connexins, connexin37 (Cx37), Cx40, and Cx43, during growth and senescence in rat aorta by en face immunoconfocal microscopy and electron microscopy. Gap junction spots labeled by specific antisera against Cx37, Cx40, and Cx43 were quantified at 1 day, 7 days, 28 days, 16 months, and > or =20 months of age, and the relationship between the connexins was examined by co-localization analysis. At birth, all three connexins were abundantly expressed; the number and total area of connexin spots then declined within 1 week (p<0.05 for each connexin). From 1 week, each connexin showed a distinct temporal expression pattern. Whereas Cx43 signal decreased progressively, Cx37 signal fluctuated in a downward trend. By contrast, Cx40 maintained an abundant level until > or =20 months of age (> or =20 months vs. 28 days, p<0.05 for number and total connexin signal area). These patterns were associated with changes in endothelial cell morphology. Double-label analysis showed that the extent of co-localization of connexins to the same gap junctional spot was age-dependent [>70% at birth and 28 days old; <70% at later stages (p<0.05)]. We conclude that expression of the three connexins in aortic endothelium is age-related, implying specific intercellular communication requirements during different stages after birth.

Multiple connexin expression in regenerating arterial endothelial gap junctions

Endothelial cells form gap junctions that, according to vessel type, may be composed of up to 3 types of connexin, connexin37, connexin40, and connexin43. Although changes in connexin expression have been linked to growth and injury in cultured endothelial cells, information on connexin expression in regenerating endothelium in situ is lacking. We investigated gap junction distribution and expression of all 3 endothelial connexins during healing in rat carotid artery after denudation injury. En face viewing of the vascular luminal surface by means of immunoconfocal microscopy was used to examine the spatial and temporal expression pattern of the endothelial connexins. Gap junction spots labeled by specific antisera against connexin37, connexin40, and connexin43 were quantified 7, 14, and 28 days after injury, and the relations among the connexins were examined by using colocalization analysis. Complementary electron microscopy was also conducted. After injury, the regenerating endothelium initially expressed small, sparse gap junctions, the numbers of which progressively increased to values equivalent to those of controls. Although connexin40 gap-junctional spot size and area returned to uninjured levels by 28 days after injury, connexin37 and connexin43 spot size and area exceeded those of the uninjured artery (P<0.05). Double-label analysis showed that even though colocalization of connexins to the same gap-junctional spot is a common feature, the extent of colocalization was time dependent (>80% in the intact artery at postinjury day 28 and <70% at postinjury days 7 and 14, P<0.01). We conclude that distinct alterations in expression of the 3 connexins are associated with regeneration of the arterial endothelium in situ, implying different intercellular communication requirements during the various phases of the healing process.

Cholesterol-induced changes of type VIII collagen expression and distribution in carotid arteries of rabbit

Lipoproteins play a major role in cardiovascular disease and atherosclerosis. In the vascular wall, they strongly influence the organization of extracellular matrix. The present study set out to investigate the changes in the extracellular matrix of the vessel wall induced by atherogenic diet, focusing on type VIII collagen, a vascular collagen that has not previously been investigated in detail. The influence of cholesterol diet on the expression, distribution, and deposition of type VIII collagen was examined in carotid arteries of New Zealand White rabbits. Carotid arteries of rabbits receiving diet supplemented with 1% cholesterol for 6 weeks and those on the same regimen followed by normal chow for 1 day, 10 days, 5 weeks, and 12 weeks were studied and compared with controls not exposed to the cholesterol diet. Carotid arteries of normocholesterolemic rabbits contained type VIII collagen-expressing cells in all layers, with focal accumulations of expressing cells in the subendothelial areas, the outer medial zone, and the adventitia. In response to cholesterol diet, type VIII collagen synthesis was reduced in media and adventitia and the distribution patterns changed. Expressing cells were found predominantly in the endothelium, and type VIII collagen accumulated in the intimal space. Immunogold labeling for electron microscopy revealed that type VIII collagen in the intima is associated with microfibrils extending from the internal elastic lamina. Withdrawal of cholesterol resulted in reestablishment of the normal distribution pattern. Northern and Western blot analyses supported the immunoconfocal and in situ hybridization data, demonstrating decreased type VIII collagen expression in response to cholesterol diet and progressive recovery to normal levels with time after withdrawal of cholesterol. Our study demonstrates that type VIII collagen is modulated in the presence of cholesterol. The data indicate that type VIII collagen is specifically remodeled during early experimental atherosclerosis, implying a role for this extracellular matrix component in neointimal growth.

In vitro inducible nitric oxide synthesis inhibitory active constituents from Fraxinus rhynchophylla

Bioassay-guided fractionation of an H2O extract of the barks of Fraxinus rhynchophylla has furnished two inducible nitric oxide synthase (iNOS) inhibitory compounds, ferulaldehyde (1) and scopoletin (3) together with a coumarin, fraxidin (2). Compounds 1 and 3 showed inhibition of nitric oxide (NO) synthesis in a dose-dependent manner by murine macrophage-like RAW 264.7 cells stimulated with interferon-gamma (IFN-gamma) plus lipopolysaccharide (LPS). The inhibition of NO synthesis of 1 was reflected in the decreased amount of iNOS protein, as determined by Western blotting.

Inverse relationship between connexin43 and desmin expression in cultured porcine aortic smooth muscle cells

Our previous work has shown that in vascular tissues the elastic medial regions express high levels of the gap junctional protein, connexin43, but low levels of desmin, while the muscular medial regions express low levels of connexin43 but high levels of desmin. It is uncertain, however, whether this regional difference at the tissue level extends down to the level of the individual cell, or reflects an averaged relationship of groups of cells of different connexin43 and desmin expression. The present study has addressed this question using cultured porcine aortic smooth muscle cells. Immunoconfocal microscopic analysis of single-labeled cells showed that while smooth muscle alpha-actin, calponin and vimentin were positively labeled in the majority of medial smooth muscle cells both in intact porcine aorta and corresponding cultured cells, desmin and connexin43 labeling was highly heterogeneous. In the cultured cells, 0.3-0.5% of cells were found to be desmin-positive, and quantitative analysis after double labeling for desmin and connexin43 revealed that the desmin-positive cells were smaller, and contained significantly lower numbers and smaller sizes of connexin43 gap-junctional spots than did desmin-negative cells. Our findings demonstrate that an inverse expression pattern of connexin43 and desmin holds true at the level of the individual cell. This suggests a close relationship between intrinsic phenotypic control and the regulation of connexin43 expression in the arterial smooth muscle cell.

Differential expression of connexin43 and desmin defines two subpopulations of medial smooth muscle cells in the human internal mammary artery

Upregulation of connexin43-gap junctions is associated with transition of contractile vascular smooth muscle cells (SMCs) to the synthetic state. To determine whether phenotypically distinct subpopulations of medial SMCs differentially express connexin43, we investigated the human distal internal mammary artery, a structurally heterogeneous vessel with features ranging from elastic to elastomuscular to muscular. Immunoconfocal microscopy combined with quantitative analysis and complemented by in situ hybridization showed that SMCs in the elastic medial regions expressed high levels of connexin43 but low levels of desmin, whereas those of muscular medial regions expressed low levels of connexin43 but high levels of desmin. Ultrastructurally, SMCs of both regions were of the contractile phenotype, but the former cells were irregular in shape with relatively prominent synthetic organelles whereas the latter were spindle shaped with fewer synthetic organelles. Vimentin, smooth muscle alpha-actin, calponin, h-caldesmon, and myosin heavy chains (SM1 and SM2) were equally highly expressed by most cells in both subpopulations. The connexin43/desmin expression pattern of SMCs in regions of intimal thickening resembled those of elastic medial regions. These findings refine the view suggested from previous studies that high levels of connexin43 expression are associated with SMCs of a less contractile/more synthetic phenotype. In the internal mammary artery, the 2 subpopulations of SMCs with markedly different connexin43 expression levels both represent a differentiated contractile phenotype, but the subpopulation showing high levels of connexin43-gap junctions is characterized by low levels of desmin and structural features that reflect a more synthetic tendency.

Connexin make-up of endothelial gap junctions in the rat pulmonary artery as revealed by immunoconfocal microscopy and triple-label immunogold electron microscopy

Integration of vascular endothelial function relies on multiple signaling mechanisms, including direct cell-cell communication through gap junctions. Gap junction proteins expressed in the endothelium include connexin37, connexin40, and connexin43. To investigate whether individual endothelial cells in vivo express all three connexin types and, if so, whether multiple connexins are assembled into the same gap junction plaque, we used affinity-purified connexin-specific antibodies raised in three different species to permit multiple-label immunoconfocal and immunoelectron microscopy in the rat main pulmonary artery. Immunoconfocal microscopy showed a high incidence of co-localization between connexin43 and connexin40, but lower incidences of co-localization between connexin37 and connexin40 or connexin43. Immunoelectron microscopy revealed that 83% of gap junction profiles contained all three connexins, with the proportion of connexin40 labeling being significantly higher than that of connexin37 or connexin43. The presence of three different connexin types of distinct properties in vitro provides potential for complex regulation and functional differentiation of endothelial intercellular communication properties in vivo.

The Gln-Arg 191 polymorphism of the human paraoxonase gene is not associated with the risk of coronary artery disease among Chinese in Taiwan

Paraoxonase (PON1) is a high density lipoprotein-associated enzyme capable of hydrolyzing lipid peroxides, and thus, might protect lipoproteins from oxidation. A common polymorphism due to an amino acid substitution (Gln-Arg) at codon 191 is considered to be a major determinant of variation in serum PON1 activity. Recent studies have suggested that the PON1-191 polymorphism is an independent risk factor for coronary atherosclerosis in patients with or without diabetes mellitus. The association of PON1-191 polymorphism genotypes and coronary artery disease (CAD) among Chinese subjects in Taiwan was examined. The genotype of 218 angiographically documented CAD patients and the same number of age- and sex-matched control subjects was determined. Genotypes AA, AB and BB were present in 25 (11%), 102 (47%) and 91 (42%) of control subjects, respectively, and in 30 (14%), 96 (44%) and 92 (42%) of CAD patients, respectively (chi2 = 0.57, P = 0.75 between groups). The frequency of the A allele was 0.36 for the control group and 0.35 for CAD patients (P = 0.94). No significant differences in the PON1-191 genotype frequencies could be found between groups when multivariate logistic regression analysis was performed, or different subgroups of age, sex or risk factors were analyzed. Among control subjects, there was also no significant difference between genotypes of the PON1-191 polymorphism and various clinical and lipid variables. In conclusion, our data suggest that there is no association between the Gln-Arg 191 polymorphism of the human PON1 gene and CAD among Chinese subjects in Taiwan.

Predictors of systemic embolism in patients with mitral stenosis. A prospective study

BACKGROUND

Most studies of the predictors of systemic embolism in patients with mitral stenosis have been retrospective.

OBJECTIVE

To prospectively study factors associated with systemic embolism in mitral stenosis.

DESIGN

Prospective cohort study.

SETTING

University-affiliated medical institution with 3000 beds.

PATIENTS

534 consecutive patients with a mitral valve area of 2.0 cm2 or less; 132 patients were in sinus rhythm, and 402 were in atrial fibrillation.

MEASUREMENTS

Nine clinical and 10 echocardiographic variables were assessed for prediction of systemic embolism over a mean (+/- SD) follow-up of 36.9 +/- 22.5 months. Diagnosis of systemic embolism was based on symptoms and signs (sudden onset of peripheral arterial ischemic or neurologic manifestations without prodromes) and on findings on computed tomography, angiography, and surgery.

RESULTS

For patients in sinus rhythm, age (relative risk [RR], 1.12 [95% CI, 1.04 to 1.21]), the presence of a left atrial thrombus (RR, 37.1 [CI, 2.82 to 487.8]), mitral valve area (RR, 16.9 [CI, 1.53 to 187.0]), and the presence of significant aortic regurgitation (RR, 22.4 [CI, 2.72 to 184.8]) were positively associated with embolism. For patients in atrial fibrillation, previous embolism (RR, 3.11 [CI, 1.66 to 5.85]) was positively associated with embolism; percutaneous balloon mitral commissurotomy (RR, 0.37 [CI, 0.18 to 0.79]) was a negative predictor.

CONCLUSIONS

It may be prudent to give anticoagulants not only to patients in atrial fibrillation and patients with previous systemic embolism but also to those showing a left atrial thrombus or significant aortic regurgitation on echocardiography. Early percutaneous balloon mitral commissurotomy may also help prevent systemic embolism in patients with mitral stenosis.

Unusual coronary artery ectasia and stenosis in a patient with systemic lupus erythematosus and acute myocardial infarction

Acute myocardial infarction is an important and sometimes fatal complication of systemic lupus erythematosus (SLE). We describe a case of acute myocardial infarction in a 23-year-old woman with SLE. Angiography revealed coronary ectasia in the left main and proximal circumflex coronary arteries, as well as a stenotic lesion in the left anterior descending artery. The possible pathophysiology is discussed.

On-line multiplane transesophageal echocardiography for balloon mitral commissurotomy

This study describes in detail the technique and results of on-line multiplane transesophageal echocardiographic guidance of balloon mitral commissurotomy in 150 consecutive patients with symptomatic mitral stenosis. The mitral valve area improved significantly and there were no in-hospital deaths, strokes, or emergency valve operations.

Transluminal coronary angioplasty and stenting in a patient with single coronary artery and acute myocardial infarction

An isolated single coronary artery is a rare congenital anomaly with an incidence of 0.03% to 0.4% and can present additional hazards such as myocardial ischemia, infarction, or sudden death in individuals with atherosclerotic changes in this artery. Herein, we report an acute anterior and inferior wall infarction in a 61-year-old male patient with the right coronary artery arising as a branch of the left coronary artery. Selected coronary angiography showed a 90% stenosis in the left anterior descending artery proximal to the origin of the right coronary artery. The patient underwent successful percutaneous transluminal coronary angioplasty and stenting without compromising the flow to the anomalous right coronary artery. There has been no previous reports of percutaneous transluminal coronary angioplasty and coronary stenting in a patient with this anomaly.

Interaction between obesity and genetic polymorphisms in the apolipoprotein CIII gene and lipoprotein lipase gene on the risk of hypertriglyceridemia in Chinese

To understand the effects of the interaction between genetic polymorphisms and obesity on the risk of hypertriglyceridemia (HTG), two polymorphisms, an SstI polymorphism on the apolipoprotein CIII gene and a HindIII polymorphism on the lipoprotein lipase gene, were analyzed in 339 Chinese subjects with (82 cases in the HTG group) or without HTG (257 cases in the control group). Our data revealed that the frequencies of obesity, the SstI minor allele (S2), and the HindIII major allele (H+) in the HTG group were significantly higher than in the control group. Subgroup analysis revealed that the association between these two polymorphisms and HTG occurred predominantly in nonobese subjects and in subjects with the less hypertriglyceridemic genotype of another polymorphism. Multivariate logistic regression analysis showed that all three risk factors (obesity, S2-containing chromosome, and H+ homozygosity) were associated with HTG, and an interaction was found between obesity and H+ homozygosity for the occurrence of HTG. The risk of HTG increased significantly with combinations of risk factors. Subjects can be divided into low or high risk groups for HTG using such combinations. These results provide evidence of interaction between obesity and the HindIII polymorphism of the lipoprotein lipase gene on the risk of HTG.

Angiotensinogen and angiotensin-I converting enzyme gene polymorphisms and the risk of coronary artery disease in Chinese

The homozygous deletion allele (DD) of the angiotensin-I converting enzyme (ACE) gene and the T235 homozygote of the angiotensinogen (AGT) gene have been reported to be correlated with an increased prevalence of coronary artery disease (CAD) and myocardial infarction (MI). The importance of the DD genotype and T235 homozygote as genetic risk factors for CAD in Chinese remains uncertain. This study included 426 patients who underwent coronary angiography and 180 healthy subjects without clinical evidence of CAD. Coronary angiography identified 268 patients with CAD (CAD group) and 158 patients without CAD. The healthy subjects and patients without angiographic evidence of CAD constituted the control group. Three polymorphisms were studied: an insertion/deletion (I/D) polymorphism of the ACE gene and the T174 M and M235T polymorphisms of the AGT gene. No association was found between any of the three studied polymorphisms and the risk of CAD or MI in Chinese using univariate or multivariate analysis. In multivariate analysis, the relative risks were 1.20 (95% confidence interval = 0.91-1.61, P = 0.20) for the DD genotype, 1.05 (95% CI = 0.82-1.35, P = 0.69) for the T174 homozygote, and 1.19 (95% CI = 0.91-1.55, P = 0.20) for the T235 homozygote. Similarly, no significant difference was found in the frequencies of the DD genotype and the T174 and T235 homozygotes between the control group, the CAD group, the non-MI group, and the MI group when analyzed according to sex, age, or degree of risk. Our data suggest that neither the DD genotype of the ACE I/D polymorphism nor the T174 and T235 homozygotes of the AGT gene confer significant risk for CAD or MI in Chinese.

The G1691A mutation of the coagulation factor V gene (factor V Leiden) is rare in Chinese: an analysis of 618 individuals

To understand the allele frequency of the G1691A mutation of the coagulation factor V gene (factor V Leiden) in Chinese, 618 Chinese individuals, including 54 cases with venous thrombosis, were analyzed. Only one case in the control group was heterozygous for the 1691G allele and the 1691A allele. Our data suggest that the factor V Leiden is rare in Chinese.

Perforated appendicitis in a 4-month-old infant

A 4-month-old male infant was admitted to our hospital because of poor intake and mild abdominal distention for 1 day. Fever and watery diarrhea had occurred 4 days prior to admission, but subsided 2 days later after taking oral medications. A physical examination showed an acute ill-looking baby with a soft and mildly distended abdomen. The bowel sound was hypoactive and no obvious abdominal tenderness was found. Normal leukocyte and differential counts were noted in initial laboratory examinations; however, the serum level of C reactive protein was extremely high (31.4 mg/dL). Progressive abdominal distention and bilious vomiting occurred. Serial plain films of abdomen showed ileus with a fixed gas pattern and an abdominal echo revealed intraperitoneal fluid accumulation. Under the impression of intestinal perforation, an emergency laparotomy was performed. A perforated appendicitis with turbid fluid in the peritoneal cavity was noted during surgery. A pus culture grew Pseudomonas aeruginosa which was sensitive to Ceftazidime only. Triple antibiotics consisting of Prostaphlin, Metronidazole, and Ceftazidime were administered for 2 weeks. The patient was discharged 3 weeks later without any complications. Appendicitis in infancy is a rare condition and associated with a high frequency of perforation and peritonitis. Diagnosis is often difficult because of variable and nonspecific clinical manifestations.

Laboratory aid and ultrasonography in the diagnosis of appendicitis in children

Forty-seven consecutive patients with clinically suspected acute appendicitis were studied at this hospital from June, 1994 to March, 1995. All the patients had received a complete study protocol including: detailed history and physical examination; complete blood cell count with differential count; erythrocyte sedimentation rate; C-reactive protein and sonographic examination. The male to female ratio is 29: 18. The age range is from 4 to 14 years. Thirty patients received laparotomy and 27 were diagnosed as appendicitis by histologic findings including 6 cases of perforated appendicitis. The remaining 3 patients had no evidence of appendicitis histologically. The other 17 patients were observed clinically. In these, the abdominal pain resolved spontaneously, or it was proved due to other diseases. The sensitivity and specificity of these laboratory examinations are: leukocytosis (> 10,000/mm3): 85. 2%, 65%; leukocytosis with a shift-to-the-left (neutrophil > 75%): 81.5%, 70%; elevated ESR (> 20 mm/hr): 40.7%, 85%; elevated CRP (> 0.9 mg/dl): 70.4%, 65%; (> 5 mg/dl); 51.9%, 95%; sonography: 85.2%, 100%. There were 4 false-negative and no false-positive ultrasonographic results in our study. Five of the 6 case of perforated appendicitis had elevated CRP levels of more than 8 mg/dl. In conclusion, detailed history taking and physical examination are still the most reliable tools for diagnosis. For the doubtful cases, sonography can provide excellent specificity and good sensitivity for differential diagnosis. The classical tools of leukocytosis and shift-to-the-left can only provide a screening property but not for diagnosis. CRP was not a good predictor in our study, but it can be a useful parameter when perforated appendicitis is suspected.

Abdominal teratomas in children

Seventeen cases of abdominal teratoma were studied retrospectively. These patients had been diagnosed at Cathay General Hospital from 1978 to 1993. The male to female ratio was 9:8, the range of age at diagnosis was from 2 days to 13 years. The chief complaints were palpable abdominal mass in 13 patients (76%) and abdominal distention in 7 (41%). Fifteen teratomas were located in the retroperitonium; also, 1 of the 17 had gastric teratoma and another, a tumor originating from an undescended testes. The tumors were resected in all patients. Postoperative courses were smooth except for one patient, who died suddenly on the day following surgery. No further specific management was needed because the pathologic findings were all benign in nature. Ultrasonography is of benefit in locating, as well as diagnosing, abdominal teratoma. Surgical excision is curative for the majority of cases. Long term follow-up is necessary, in consideration of the rare chance of recurrence.

Carcinoma of the colon in a child

A 13-year-old boy presented with carcinoma of the ascending colon. He had had intermittent abdominal pain for about one year, with body weight loss, prior to admission. Physical examination showed diffuse abdominal tenderness, but no palpable mass. Lower GI barium study and colonofibroscopic examination showed a protruding mass over the proximal ascending colon. At operation, right hemicolectomy with ileotransversecolostomy was performed, the pathologic finding was adenocarcinoma, signet-ring cell type. Although chemotherapy with 5-fluorouracil, mitomycin, and levamisole were given subsequently, the patient expired one year after surgery because of multiple metastasis. Carcinoma of the colon is extremely rare in the young. Mucin-producing adenocarcinoma is the most predominant type of colon cancer, and most are of signet-ring cell carcinoma. While prognosis is relatively bright in adult, the prognosis is quite unfavorable in children because of the preponderance of the poor histological characteristics and the difficulty of diagnosis.

[Clinical significance of changes in the serum level of endogenous digitalis-like factor in patients with chronic congestive heart failure]

Determination of serum endogenous digitalis-like factor (EDF) concentration was carried out in 52 patients with chronic congestive heart failure with radioimmunoassay. The results showed that concentration of serum EDF in patients with chronic congestive heart failure was significantly lower than that in normal subjects (P less than 0.001). The lowering of serum EDF concentration was significantly negatively correlated with the severity of heart failure, r = 0.6475, P less than 0.001. Age had no significant effect on serum EDF concentration (P greater than 0.05). Serum EDF concentration rose after the heart failure was treated, but was still lower than that in normal subjects (P less than 0.01). Serum EDF concentration in patients with coronary heart disease was the lowest and in patients with hypertension the highest.