Immunological detection of membrane-associated human luteinizing hormone correlates with gene expression in cultured human cancer and fetal cells

We have demonstrated the expression of membrane-associated hCG and its subunits and fragments by cells from 78 human cancer cell lines of different types and origins, indicating that such expression is a common phenotypic characteristic of cultured human malignant cells. Because human (h) LH beta has 80% homology with hCG beta and is coded by one of the seven genes in the gene cluster located in chromosome 19, it was important to determine whether hLH and its beta-subunit are also expressed as membrane-associated proteins by cells from human cancer cell lines. Thus, 11 cancer cell lines of different types and origins were adapted to grow in serumless medium, with Nutridoma-HU or SP as serum substitute, and analyzed by flow cytometry using two monoclonal antibodies directed to different conformational epitopes of intact hLH and a monoclonal antibody reacting with an epitope of hLH beta-free. The cells were also analyzed simultaneously for the expression of hCG and its subunits and fragments. Determination of translatable levels of hLH beta and hCG beta messenger RNAs (mRNAs) was performed in cells from some of the cancer cell lines, including the JEG-3 choriocarcinoma cell line, and in cells from a human fetal lung cell line. The analytical flow cytometry studies showed that in addition to the expression of membrane-associated hCG in all of its forms, expression of membrane-associated intact (holo) hLH and its free beta-subunit occurred in every case. These findings were corroborated by the presence of translatable levels of hLH beta and hCG beta mRNAs in all of the cancer cell lines analyzed, indicating that the expression of these membrane-associated glycoproteins is a phenotypic characteristic of human cancer cells and that the activation of the hCG beta-hLH beta gene cluster is nonselective. The presence of translatable levels of hCG beta-hLH beta mRNAs in the cultured human fetal lung cells punctuates once more the in vivo and in vitro biochemical similarities between fetal and cancer cells.     

In Vitro antimicrobial susceptibilities of Streptococcus pneumoniae isolated from two teaching hospitals in Taiwan, 1989-1995

The susceptibility of 46 pneumococcal isolates collected during October 1989 to May 1995 from National Taiwan University Hospital and Taipei Municipal Yang Ming Hospital was studied. Among these isolates, the resistant rate of penicillin G was 21.7%; the penicillin G-resistant strains were more frequently resistant than the penicillin-sensitive strains to other beta-lactam antimicrobial drugs. The minimum bactericidal concentrations (MBCs) of penicillin G for all isolates were equal to, or one dilution higher than, minimum inhibitory concentrations (MICs). Three strains were false positive for penicillin resistance among isolates of Streptococcus pneumoniae screened with oxacillin. On the other hand, resistance to penicillin G was often independent of resistance to erythromycin. Vancomycin was the most active agent tested.     

Molecular structural basis of ligand selectivity for 5-HT2 versus 5-HT1C cortical receptors

A molecular structural criterion of ligand selectivity for the 5-HT2 versus 5-HT1C receptor was hypothesized on the basis of radioligand binding data. Despite the large number of compounds which have been tested at both receptors, analysis of published data led to the identification of only five agents which are greater than 10-fold selective for the 5-HT2 versus the 5-HT1C receptor. Comparison of the two-dimensional structures revealed that, although these five compounds represent three distinct structural classes, they share a common structural feature located in the region hypothesized to be involved in receptor binding: a carbonyl or carboxyl oxygen interposed spatially between an aromatic ring and nitrogen atom. This structural feature was used to predict the relative selectivity of compounds that had not previously been analyzed at both the 5-HT2 and 5-HT1C receptors. All six drugs tested which contain the identified reactive carbonyl or carboxyl group were found to be selective for the 5-HT2 versus the 5-HT1C receptor with selectivity ratios ranging from 26 to 380. By contrast, three agents which are structurally similar but do not contain the reactive carbonyl or carboxyl group displayed equally high affinity for both receptor binding sites. Since the physiological roles of the 5-HT2 and 5-HT1C receptor are markedly different, it would be of potential clinical and scientific value to utilize this molecular structural feature to further identify chemical compounds which would selectively interact with only one of the two receptors.     

Stereotactic core biopsy of breast microcalcifications. Aid to diagnosis?]

We assessed the accuracy with which stereotactic core biopsy of breast microcalcifications helps to justify follow-up or indicate required surgical planning. Eighty-nine patients underwent stereotactic breast biopsy performed with large core needles. Histopathologic findings of microbiopsies were correlated with radiological findings, with follow up and with surgical findings. Agreement between radiological and histopathologic findings on biopsies was obtained in 86% for benign results. Even in the case of benign radiological findings, the histological results of microbiopsies required a surgical biopsy justified in 10% of cases. Radiologically suspicious or malignant microcalcifications were correlated with 35% benign and 65% malignant histologies on biopsies. The positive predictive value, negative predictive value and accuracy were respectively 93%, 86% and 95%. Invasive lesions were found on microbiopsies in 39% of excised malignant lesions. Multifocal lesions were proved on microbiopsies in 50% of all excised carcinomas. Microbiopsies help to disclose malignant lesions undetected on radiological analysis, and may obviate diagnostic surgical biopsy in many cases.     

Detection and deletion of motion artifacts in electrogastrogram using feature analysis and neural networks

Electrogastrogram is a surface measurement of gastric myoelectrical activity, and electrogastrography has been an attractive method for physiological and pathophysiological studies of the stomach due to its noninvasive nature. Motion artifacts, however, ruin the electrogastrogram (EGG), and make the analysis very difficult and sometimes even impossible. They must be eliminated from EGG signals before analysis. Up to now, this can only be done by visual inspection, which is not only time-consuming but also subjective. In this study, a method using feature analysis and neural networks has been developed to realize automatic detection and elimination of the motion artifacts in EGG recordings by computer. Experiments were conducted to investigate the characteristics of different motion artifacts. Useful features were extracted, and different combinations of the features used as the input of the neural network were compared to obtain the optimal performance for the detection of motion artifacts using the artificial neural network.     

Rubis: an extended relational system managing events Part I: specification

Dynamic aspects of information systems are taken into account in a lot of conceptual models. However, the dynamic concepts of these models have rarely been fully implemented in database management systems (DBMSs).Rubis is an extended relational DBMS which supports an extended relational schema (including event and operation concepts) and automatic control of the dynamic aspects of applications, i.e. event recognition, operation triggering and time handling.The first part of the paper contains a short presentation of the basic concepts and the specification language used for the extended schema. The second part focuses on the internal mechanisms: the temporal processor, which manages the temporal aspects of specifications and recognizes temporal events; and the event processor which manages events treatment and synchronization. These two mechanisms permit an automatic execution of the extended schema and so provide rapid prototyping capabilities. This last part will be covered in the December issue of this journal.     

Effects and mechanism of emodin and sandostatin on pancreatic ischemia in acute haemorrhagic necrotizing pancreatitis

We hypothesized that maternal serum levels of the isoenzyme creatine kinase (CK)-BB, which is highly expressed in the placenta, may be elevated during the early second trimester in gestations destined to deliver prematurely or of a small-for-gestational-age infant (birthweight below 10th percentile). To test this hypothesis, we compared maternal serum CK-BB levels and percentage of CK-BB over total CK, in 69 normal pregnancies (delivering at term of appropriate-for-gestational-age infants) with those of 25 cases complicated by preterm delivery at < or = 34 weeks (n = 14), of a small-for-gestational-age infant (n = 8), or both (n = 3). No differences were present in maternal serum CK BB levels between normal and complicated pregnancies. Moreover, no correlation was found between gestational age at delivery and CK BB levels (r = 0.03; p = 0.7).