Detection of cytoplasmic IL-1 beta in peripheral blood mononuclear cells from intensive care unit (ICU) patients.

Cytokines including IL-1 beta have been implicated in the pathophysiology of sepsis and the systemic inflammatory response. It is believed that certain critically ill patients may be 'primed' with respect to cytokine production, and that subsequent 'triggers' may cause exaggerated cytokine production in these patients with exacerbation of their clinical condition; however, no means of identifying 'primed' patients has been described. The presence of cytoplasmic IL-1 beta within peripheral blood mononuclear cells (PBMC) from patients in the ICU was investigated as a means of identifying 'primed' patients, using fluorescent antibody labelling and flow cytometry. The study revealed that PBMC from ICU patients had a different staining pattern for IL-1 beta than those from healthy subjects, and that PBMC from certain ICU patients did indeed stain strongly for IL-1 beta; however, the presence of these strongly staining cells was not associated with clinical condition or outcome. It is concluded that whilst it might be possible to identify 'primed' patients in the ICU using this technique, this is of no clinical value as a predictor of clinical course.     

A Possible Correlation Between Growth-Factor Sensitivity and Response to Mitoxantrone Treatment in a Murine Myeloid Leukaemia (SA7HD) Cell Line

SA7 murine myeloid leukaemia cells usually respond to stimulation in vitro by WEHI-conditioned medium by displaying increased dose-dependent proliferation. However, at recurrence following in vivo treatment of the leukaemia with mitoxantrone, the leukaemia cells developed significant insensitivity (p - 0.04) to stimulation by WEHI-conditioned medium. This altered growth-factor sensitivity was detected when two different assays were used. The recurrent leukaemic cells were morphologically indistinguishable from untreated leukaemic cells, but in normal mice they regained sensitivity to growth factors after a single transplant. The recurrent leukaemic cells were significantly resistant to some concentrations of mitoxantrone in vitro (p = 0.012). The magnitude of this resistance was mainly a function of the dose of mitoxantrone used in the initial treatment of the leukaemia. These data suggest an association between growth-factor sensitivity and response to mitoxantrone treatment including the development of resistance in the SA7HD murine myeloid leukaemia cell line.     

Tumor vascular signals in renal masses: detection with Doppler US

The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.     

Cytokine induction of neopterin production.

The pteridine neopterin is a marker of immunological activation and has been shown to be a useful marker of graft-versus-host disease (GVHD) in bone marrow transplant patients. High levels of both neopterin and interferon-gamma (IFN-gamma) were produced in vitro during mixed lymphocyte responses, which may be considered to be a model of the primary events leading to GVHD. Neopterin was shown to be produced by monocytes in response to stimulation with IFN-gamma, but not other cytokines. However, the interleukins IL-1 alpha, IL-1 beta, IL-2, and tumour necrosis factor (TNF) alpha and beta, but not IL-6, stimulated neopterin production by unfractionated peripheral blood mononuclear cells (PBMC), and culture supernatants from PBMC stimulated with IL-1 alpha, IL-1 beta, IL-2 and IL-6, but not TNF-alpha or TNF-beta induced neopterin production following transfer to fresh monocyte cultures. It therefore appears that cytokines may generate neopterin by induction of IFN-gamma, by synergy with low levels of induced IFN-gamma, or by non-IFN-gamma-dependent mechanisms.     

Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos

In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture environment differs from in-vivo conditions in that the oxygen concentration is higher, and in such conditions the mouse embryos show a higher concentration of reactive oxygen species (ROS) in simple culture media. ROS are believed to cause damage to cell membranes and DNA fragmentation in somatic cells. This study was conducted to ascertain the level of H2O2 concentration within embryos and the morphological features of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31 fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was obtained from the IVF-embryo transfer programme. The relative intensity of H2O2 concentrations within embryos was measured using 2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence imaging and DNA fragmentation was observed with transmission electron microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/- SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed only in fragmented embryos, and was absent in non-fragmented embryos. Electron microscopic findings confirmed apoptotic bodies and cytoplasmic condensation in the fragmented blastomeres. We conclude that there is a direct relationship between increased H2O2 concentration and apoptosis, and that further studies should be undertaken to confirm these findings.      

Ultrastructural studies of interactions of B16 melanoma cells and normal mouse skin fibroblasts in the three-dimensional collagen gels in vitro

In the in vivo system, cancer metastasis is a complex multi-step process. We have utilized an in vitro three-dimensional system to study the initial stages of tumour cell invasion. In this communication, the sequence of events in interactions between B16 melanoma cells and normal mouse skin fibroblasts are described. It is proposed that tumour cells produce a "retractive factor" which induces the underlying fibroblasts to retract so as to facilitate invasion and metastasis.     

Introducing anticipated recovery pathways: a teaching hospital experience

Integrated Care Plans, or Anticipated Recovery Pathways, embrace quality and efficiency concepts. They allow multidisciplinary input on patient care planning. Pathways are now being developed hospital-wide. Discusses their development and implementation.