Actinomycin D, C2 and VII, inhibitors of Grb2-SHC interaction produced by Streptomyces

Actinomycin D, C2 and VII, cyclic peptides, inhibited Grb2 SH2 domain association (IC50 5-7 microM) with a phosphotyrosine containing peptide derived from the Shc protein (pTyr317). Actinomycins are the first examples of nonphosphorylated natural ligands of SH2 domain.     

Thrombopoietin: a potential T-helper lymphocyte stimulator. Change in T-lymphocyte composition and blood cytokine levels in thrombopoietin cDNA transferred mice

The aim of this study was to evaluate the effect of thrombopoietin (TPO) on T lymphocyte in Balb/c mice delivered hTPO cDNA with plasmid vector. Both mature and immature T lymphocytes in central organs increased, but only the CD4+ subset was preferably proliferated in circulation. High serum IFN-gamma was coinciding with the declination of platelet counts, but TNF-alpha was positively associated with the platelet count, while high IL-2 level was similar to the course of TPO expression. Our data suggested that TPO is a stimulator for T lymphocytes, especially the CD4+ subset.     

Apoptosis of cardiac myocytes in Gsalpha transgenic mice

We examined the potential involvement of two CC chemokine receptors (CCRs), CCR-1 and CCR-3, in the functional activation of granulocyte-macrophage colony-stimulating factor (GM-CSF) plus interleukin-4 (IL-4)-generated human peripheral blood monocyte-derived immature dendritic cells (DCs). Flow cytometric analysis showed that CCR-1, CCR-3, CCR-5, and CXC chemokine receptor (CXCR)-4 were expressed on the cell surface of monocyte-derived DCs. Treatment with a monoclonal antibody (MoAb) to either CCR-1 or CCR-3 but not MoAbs to CCR-5 and CXCR-4 abolished chemotactic migration of monocyte-derived DCs. The DCs treated with either the anti-CCR-1 MoAb or anti-CCR-3 MoAb were less efficient than untreated DCs in proliferation of allogeneic T cells (TCs) and TC-derived secretion of interferon-gamma (IFN-gamma). The homotypic aggregation of DCs and heterotypic aggregation of DCs with TCs were suppressed by the anti-CCR-1 MoAb or anti-CCR-3 MoAb. These results indicate that CCR-1 and CCR-3 specifically regulate interaction of TCs and DCs in the process of antigen presentation.     

Video-assisted thoracoscopic surgery to the upper thoracic spine

BACKGROUND: The standard open technique for exposure of the upper thoracic spine, T1-T4, usually requires a difficult thoracotomy. From November 1, 1995 to June 30, 1997, eight patients underwent video-assisted thoracoscopic spinal surgery in our institute to treat their upper thoracic spinal lesions endoscopically. METHODS: A new approach, the so-called "extended manipulating channel method," was used in this series that allows the combined use of video-assisted thoracoscopy and conventional spinal instruments to enter the chest cavity freely for the procedures. Patients' ages ranged from 44 to 89 years (average, 60 years). Definitive diagnoses included two pyogenic spondylitis and six spinal metastases. Five patients presented initially with myelopathy. RESULTS: There were no deaths or neurologic injuries associated with this technique. The mean surgical time was 3.1 h. The mean duration of chest tube retention was 3.3 days. The mean total blood loss was 1,038 ml, and two patients had a blood loss of more than 2,000 ml owing to bleeding from epidural veins or raw osseous surfaces. Complications included one superficial wound infection and one subcutaneous emphysema that resolved spontaneously. In this series, there was no need of conversion to open thoracotomy for the patients. CONCLUSIONS: The thoracoscopy-assisted spinal technique using the extended manipulating channels, usually 2.5-3.5 cm, allows variable instrument angulations for manipulation. The mean surgical time (3.1 h) was considered no longer than for an open technique for the equivalent anterior procedure. Such an approach can achieve less procedure-related trauma and has proved to be a good alternative to other treatment modalities.     

Profiles of chicken macrophage effector functions

In contrast to the mammalian system, avian species lack the so-called "resident" or "harvestable" macrophage population in the abdominal exudate. However, macrophages can be recruited into the chicken's abdominal cavity (presumably from the blood monocyte pool) if an inflammatory agent such as Sephadex is injected. The kinetics of inflammatory cell recruitment in terms of time, cell type, and state of activation to perform a particular effector function is currently an active area of research. This report will provide information on several chicken macrophage effector functions, including in vivo chemotaxis, phagocytosis, bacterial uptake and killing, biosynthesis of nitric oxide and various enzymes, and monokines such as interleukin-1 and granulocyte colony-stimulating factor.     

The relationship between cognition and action: performance of children 3 1/2-7 years old on a Stroop-like day-night test

One hundred and sixty children 3 1/2-7 years of age (10 M, 10 F at each 6-month interval) were tested on a task that requires inhibitory control of action plus learning and remembering two rules. They were asked to say "day" whenever a black card with the moon and stars appeared and to say "night" when shown a white card with a bright sun. Children < 5 years had great difficulty. They started out performing well, but could not sustain this over the course of the 16-trial session. Response latency decreased from 3 1/2 to 4 1/2 years. Children < 4 1/2 years performed well when they took very long to respond. To test whether the requirement to learn and remember two rules alone was sufficient to cause children difficulty, 80 children 3 1/2-5 years old were tested on a control version of the task ("say 'day' to one abstract design and 'night' to another"). Even the youngest children performed at a high level. We conclude that the requirement to learn and remember two rules is not in itself sufficient to account for the poor performance of the younger children in the experimental condition.     

Novel T cell antigen 4-1BB associates with the protein tyrosine kinase p56lck1

4-1BB is a 30-kDa inducible T cell Ag, and is expressed predominantly as a 55-kDa dimer on both CD4+ and CD8+ T lymphocytes. The cytoplasmic tail of 4-1BB contains the sequence Cys-Arg-Cys-Pro, which is similar to the sequence Cys-X-Cys-Pro, which mediates the binding of the CD4 and CD8 molecules to the protein tyrosine kinase p56lck. An anti-4-1BB mAb, 53A2, was used to determine whether 4-1BB may associate with p56lck. The 53A2 mAb specifically recognized 4-1BB on a CD8+ T cell line, CTLL-2, and coimmunoprecipitated a 56-kDa protein along with 4-1BB. Peptide mapping indicated that the 56-kDa phosphoprotein was identical to p56lck. The coimmunoprecipitation of p56lck with 4-1BB also occurred in nonlymphoid cells such as insect (Sf-21) and HeLa cells when the two recombinant proteins were coexpressed. Analysis of mutant p56lck recombinant proteins showed that two cysteine residues critical for p56lck-CD4 (or -CD8) complex formation are also required for the p56lck-4-1BB interaction. These studies establish that 4-1BB physically associates with p56lck.     

Successful treatment with fluconazole of protothecosis developing at the site of an intralesional corticosteroid injection

We report a case of cutaneous protothecosis treated successfully with oral fluconazole. Fluconazole appears to be an effective alternative to conventional drugs for the treatment of cutaneous protothecosis. Cutaneous protothecosis is an uncommon infection due to achlorophyllic, saprophytic, algae-like unicellular organisms of the genus Prototheca that occurs mainly in immunocompromised patients. To date there is no standard treatment regimen. Surgical excision, oral ketoconazole, intravenous amphotericin B alone or in combination with oral tetracycline have been reported to be effective in the management of protothecosis. We report a 55-year-old immunocompetent woman with cutaneous protothecosis which developed at the site of intralesional triamcinolone acetonide injection, who was successfully treated with oral fluconazole.     

Establishment and characterization of human gastric carcinoma cell lines

We report 8 newly established gastric-carcinoma cell lines (SNU-216, 484, 520, 601, 620, 638, 668, 719) from Korean patients. Morphologic study was carried out using light and electron microscopes. CEA, alpha FP, and CA 19-9 and TPA in supernatant and in cell lysate were measured by radioimmunoassay. p53 and c-Ki-ras gene mutations were screened and confirmed by sequencing. The cell lines, derived from tumors with moderate differentiation, grew as a diffuse monolayer, and those from tumors with poor differentiation and minimal desmoplasia grew exclusively as non-adherent. Out of the 8 gastric-cancer cell lines, 5 had detectable levels of CEA both in supernatant and in cell lysate; there was no expression or secretion of alpha FP in these cells; 4 cell lines showed high levels of CA 19-9 in cell pellets. All cell lines except SNU-484 had high concentrations of TPA both in cell lysate and in supernatants. p53 mutation was found in 6 cell lines (75%): 2 (SNU-216 and SNU-668) had mutations in exon 6, and other 3 in exon 8. The c-Ki-ras mutation was found in 2 cell lines (25%), SNU-601 and SNU-668. The former showed GGT-to-GAT transition mutation at codon 12, while the latter showed CAA-to-AAA transversion mutation at codon 61. DNA profiles using restriction endonuclease HinfI and polymorphic DNA probes ChdTC-15 and ChdTC-114 showed different unique patterns; which suggests that these cell lines are unique and not cross-contaminated. We believe that the newly characterized gastric-cancer cell lines presented in this paper will provide a useful in vitro model for studies related to human gastric cancer.