Categorization of Hospital Emergency Services—Developing Valid Criteria

In a pilot project sponsored by the California State Emergency Medical Services Authority, validated, verifiable criteria were developed for the vertical categorization of hospital emergency services in 11 different groupings of medical and surgical emergencies. We describe the development of an assessment process and categorization criteria to identify the most appropriate receiving facility for interfacility transfer and, in selected instances, field triage of patients with different levels of severity of illness or injury. We propose that this facility assessment project be used in the critical care planning process for the eventual vertical categorization of hospital emergency services in California and as a template for similar projects in other states.     

DNA ploidy pattern and amplification of ERBB and ERBB2 genes in human gastric carcinomas

The DNA ploidy pattern and amplification of ERBB and ERBB2 genes were examined in paraffin-embedded tissue from gastric carcinomas using flow cytometry and a slot-blot hybridization technique. The incidence of aneuploidy in well differentiated adenocarcinomas (56%) was significantly higher (p less than 0.05) than that in poorly differentiated adenocarcinomas (21%). The DNA ploidy pattern was not remarkably different between the primary tumors and metastatic deposits in lymph nodes. Of the nine specimens having an aneuploid stem cell line in the primary tumor and/or in metastases, three showed ERBB2 gene amplification and one showed ERBB gene amplification. The incidence of epidermal growth factor (EGF) immunoreactivity in tumor cells showed no difference between diploid and aneuploid tumors. These findings indicate that aneuploidy is frequently associated with amplification of ERBB and ERBB2 genes.     

Expression of several growth factors and their receptor genes in human colon carcinomas

We have examined the expression of mRNAs for epidermal growth factor (EGF), transforming growth factor-alpha (TGF-α), EGF receptor (EGFR), PDGF-A chain (PDGFA), PDGF-B chain (PDGFB) and PDGF receptor (PDGFR) genes in seven human colorectal carcinoma cell lines and 18 human colorectal carcinomas. In surgically resected specimens of the 18 colorectal tumors, TGF-α, EGFR, PDGFA, PDGFB and PDGFR mRNAs were detected at various levels in 15 (83%), 9 (50%), 18 (100%), 8 (44%) and 12 (67%), respectively. They were also detected in normal tissues. Interestingly, EGF mRNA was detected in only five (28%) of the tumors, but not in normal mucosa. Expression of EGF was also confirmed immunohistochemically in tumor cells. Of the five tumors expressing EGF, four expressed EGFR mRNA and showed a tendency to invade veins and lymphatics. All the colorectal carcinoma cell lines expressed TGF-α mRNA, and five cell lines expressed EGFR mRNA simultaneously. Production of TGF-α protein by DLD-1 and CoLo320DM cells was confirmed by TGF-α specific monoclonal antibody binding assay. The spontaneous³H-thymidine uptake by DLD-1 was suppressed by an anti-TGF-α monoclonal antibody. PDGFA and PDGFB mRNA were also expressed in four cell lines, but PDGFR and EGF mRNA was not detected. These results suggest that human colorectal carcinomas express multi-loops of growth factors and that TGF-α produced by tumor cells functions as an autocrine growth factor in human colonic carcinoma.     

Induction of interleukin 2 from a murine B cell tumor by a factor found in immune serum

The murine B cell tumor line 2 PK-3 secretes T cell growth factor activity after incubation for 6 to 48 hr with a factor present in heterologous immune serum. T cell growth factor derived from 2 PK-3 was compared with IL 2 produced by the Con A-induced T lymphoma cell line EL-4 G12. These studies indicated that T cell growth factor activities derived from both cell lines were similar with respect to m.w., pI values, and the ability to support growth of two IL 2-dependent T cell clones. Three preparations of immune sera were found to be active in the induction of IL 2 activity from 2 PK-3 cells, including rabbit anti-mouse brain, rabbit anti-complete Freund's adjuvant, and goat anti-mouse Ig. None of these preparations, however, induced IL 2 from EL-4 G12 cells. It was also observed that LPS synergized with immune serum to produce enhanced activity. Normal sera prepared from unimmunized animals were not active in the induction of IL 2 activity. Fractionation of immune serum on protein A Sepharose suggested that the IL 2-inducing agent is not IgG.     

The trimethylguanosine cap structure of U1 snRNA is a component of a bipartite nuclear targeting signal

The ability of series of U1 snRNAs and U6 snRNAs to migrate into the nucleus of Xenopus oocytes after injection into the cytoplasm was analyzed. The U snRNAs were made either by injecting U snRNA genes into the nucleus of oocytes or, synthetically, by T7 RNA polymerase, incorporating a variety of cap structures. The results indicate that nuclear targeting of U1 snRNA requires both a trimethylguanosine cap structure and binding of at least one common U snRNP protein. Using synthetic U6 snRNAs, it is further demonstrated that the trimethylguanosine cap structure can act in nuclear targeting in the absence of the common U snRNP proteins. These results imply that U snRNP nuclear targeting signals are of a modular nature.     

Isolation, partial characterization, and mode of action of Acidocin J1132, a two-component bacteriocin produced by Lactobacillus acidophilus JCM 1132.

Lactobacillus acidophilus JCM 1132 produces a heat-stable, two-component bacteriocin designated acidocin J1132 that has a narrow inhibitory spectrum. Maximum production of acidocin J1132 in MRS broth was detected at pH 5.0. Acidocin J1132 was purified by ammonium sulfate precipitation and sequential cation exchange and reversed-phase chromatographies. Acidocin J1132 activity was associated with two components, termed alpha and beta. On the basis of N-terminal amino acid sequencing and the molecular masses of the alpha and beta components, it is interpreted that the compounds differ by an additional glycine residue in the beta component. Both alpha and beta had inhibitory activity, and an increase in activity by the complementary action of the two components was observed. Acidocin J1132 is bactericidal and dissipates the membrane potential and the pH gradient in sensitive cells, which affect such proton motive force-dependent processes as amino acid transport. Acidocin J1132 also caused efflux of preaccumulated amino acid taken up via a unidirectional ATP-driven transport system. Secondary structure prediction revealed the presence of an amphiphilic alpha-helix region that could form hydrophilic pores. These results suggest that acidocin J1132 is a pore-forming bacteriocin that creates cell membrane channels through the "barrel-stave" mechanism.     

Mitogen activation of human chronic lymphatic leukemia cells. I. Synthesis and secretion of immunoglobulin.

The response of CLL (chronic lymphatic leukemia) lymphocytes to PHA, PWM, and Con A with respect to changes in surface markers and synthesis and secretion of immunoglobulin were examined. After PHA stimulation the percentage of cells bearing readily detectable surface immunoglobulin (SmIg) diminished rapidly whereas cells forming rosettes with sheep erythrocytes (E-rosettes) increased from less than 1% to 30 to 50%. The great majority of blast-transformed cells were E-rosette-positive cells with a small population of SmIg-positive blast cells also observed. Ig production in four of seven CLL lymphocyte populations was increased 2.5 to greater than 40-fold after 4 to 6 days of culture in the presence of PHA. In contrast, pokeweed mitogen did not affect Ig synthesis. Furthermore, the Ig secreted into the culture supernatant fluids from seven of eight CLL cases examined consisted almost entirely of free light chain molecules. In contrast, the cell lysates contained a significant proportion of intact Ig molecules. These results indicate that CLL cells can, under certain circumstances, be stimulated to synthesize and secrete increased amounts of Ig, but that there is a basic defect in the biosynthetic mechanism of these cells which result in the secretion of free light chains rather than intact immunoglobulin molecules.     

X-ray analysis of ferredoxin from Spirulina platensis. II. Chelate structure of active center.

A chloroplast-type ferredoxin from Spirulina platenis crystallized in an orthorhombic system, space group C2221, with cell dimensions a=62.32, b=28.51, and c=108.08 A. The electron density map at 2.8 A resolution was prepared by using the best phase angles determined by the single isomorphous replacement method coupled with the anomalous dispersion method. The chelating structure of the acitve center was revealed as follows. Of the six cysteinyl residues in the molecule, Cys 41, Cys 4k, Cys 49, and Cys 79 are involved in the active center. Cys 41 and Cys 46 are coordinated to one iron atom, and Cys 49 and Cys 79 to the other iron atom. Only one of these cysteinyl residues, Cys 79, is comparatively apart from the other three in the amino acids sequence of the molecule, as found in the case of bacterial ferredoxin. It appears that the NH....S hydrogen bonds are around the active center, as in other non-heme iron sulfur proteins.