The return of the pendulum

From 1982 to 1992, 9 cases of clinical stage I serous adenocarcinoma of the endometrium were diagnosed and treated surgically in PUMC Hospital. Of these 9 patients, myometrial invasion occurred in 8 patients, lymphatic invasion in the myometrium was demonstrated in 7 patients and 6 patients were found to have extrauterine spread. The tumors studied in this paper confirmed the aggressive behavior of this particular histologic type of endometrial carcinoma. The pathological characteristics and differential diagnosis are presented.     

Improved Compartmental Modeling and Application to Three-Phase Contaminant Transport in Unsaturated Porous Media

The compartmental modeling approach has been widely used for simulating contaminant transport in porous media and surface waters. Yet a commonly used compartmental model that has only first-order accuracy may introduce considerable numerical errors under certain circumstances. Following a review of compartmental systems and compartmental modeling methodologies, performance and limitations of such a compartmental model are discussed. In particular, improvement approaches, including multipoint, high-order, linear, and nonlinear methods, are presented in detail. Finally, a number of testing problems are examined and various compartmental models that describe three-phase (dissolved, adsorbed, and vapor phases) contaminant transport in unsaturated porous media are compared with each other and also with standard numerical and analytical counterparts. The comparisons highlight the accuracy, applicability, and limitations of different compartmental models.     

CD10 is expressed on human thymic epithelial cell lines and modulates thymopentin-induced cell proliferation

Thymic hormones such as thymopoietin (TP) have been shown to regulate thymocyte differentiation and lymphocyte activation. However, it is not known whether thymopoietin affects thymic epithelial cell (TEC) functions. In this study we have examined the effect of a five amino acid active peptide (TP5), corresponding to amino acids 32-36 of TP, on the proliferation of nontransformed clones of human TEC. Our results indicate that TP5 induced reinitiation of DNA synthesis and potentiated fetal calf serum (FCS)-induced cell growth in postnatal and fetal-derived human TEC. We also found that TEC lines express high levels of endopeptidase 24.11, a cell-surface metallopeptidase also known as the CD10 antigen. We show that TP5 is cleaved by CD10 at the surface of TEC lines, indicating that this endopeptidase may regulate TP5-induced TEC proliferation. Phosphoramidon, a specific endopeptidase 24.11 inhibitor, consistently acts in synergy with TP5 to enhance FCS-induced TEC growth. Hence, we conclude that 1) TP5 alone or in combination with FCS supports the growth of TEC lines, and 2) TEC lines express high levels of CD10, which regulates TP5-induced TEC proliferation by acting as a thymic peptide degrading enzyme.     

The N-terminal half of the influenza virus NS1 protein is sufficient for nuclear retention of mRNA and enhancement of viral mRNA translation

A collection of C-terminal deletion mutants of the influenza A virus NS1 gene has been used to define the regions of the NS1 protein involved in its functionality. Immunofluorescence analyses showed that the NS1 protein sequences downstream from position 81 are not required for nuclear transport. The capacity of these mutants to bind RNA was studied by in vitro binding tests using a model vRNA probe. These experiments showed that the N-terminal 81 amino acids of NS1 protein are sufficient for RNA binding activity. The collection of mutants also served to map the NS1 sequences required for nuclear retention of mRNA and for stimulation of viral mRNA translation, using the NP gene as reporter. The results obtained indicated that the N-terminal 113 amino acids of NS1 protein are sufficient for nuclear retention of mRNA and stimulation of viral mRNA translation. The possibility that this region of the protein may be sufficient for virus viability is discussed in relation to the sequences of NS1 genes of field isolates and to the phenotype of known viral mutants affected in the NS1 gene.     

A case of free jejunal graft for anastomotic recurrence after subtotal esophagectomy

A case of anastomotic recurrence after a radical operation for thoracic esophageal carcinoma is presented. A 68-year-old male was treated by subtotal esophagectomy and esophagogastrostomy through retrosternal route. One year after the operation he experienced dysphagia and anastomotic recurrence was detected by an upper gastrointestinal series and fiberscopy. He was admitted to our hospital for radiation therapy. The response was poor and dysphagia wasn't disappeared after radiation therapy at a dose of 10,200 rad. He was consulted to our surgical department for operative therapy. Cervical esophagectomy, partial resection of gastric tube and free jejunal transplantation for the reconstruction were performed. He had been eating anything of food after the operation.     

A counterexample in power signals space

The present author points out that in the paper by Vidyasagar (1993) on nonlinear system analysis, some of the results obtained are false. The purpose of this paper is to give a counterexample. It is shown that the set of power signals is not a vector space     

High temperature deformation mechanisms in cemented carbides and cermets studied by mechanical spectroscopy

Two model hardmetals, a pure WC–Co and a TiWCN–Co, have been studied by mechanical spectroscopy. In this work, the materials are studied up to 0.85T_m of cobalt. A parallel analysis of the materials shows that three domains are characterized by similar internal friction peaks. A region characterized by relaxations in Co, a region characterized by relaxations in the ceramics and a high-temperature region characterized by relaxations at grain boundaries are found. Two peaks are located at high temperatures in both materials. The first located at 1420 K in WC–Co and at 1520 K in TiWCN–Co for 1 Hz is attributed to grain boundary sliding. A very broad and high peak estimated for 1 Hz around 1600 K in WC–Co and above 1700 K in TiWCN–Co has only been directly observed in frequency. It is thermally activated and shows a high, apparent activation energy.     

Backscattering coefficients of H,D, and He ions from solids

Experimental data on the number-backscattering coefficient R_N, the energy-backscattering coefficient R_E, and the mean fractional energy r_E of backscattered particles are tabulated for H, D, and He ions normally incident on elemental solids. References through 1981 are covered. The dependence of R_N and R_E on incident energy is shown graphically for energies from about 10 eV to 100 keV by plotting the experimental data and the empirical formulas of Tabata et al. Graphs are provided for 36 elemental targets of atomic numbers from 6 to 92.