Comparison of the bone protective effects of an isoflavone-rich diet with dietary and subcutaneous administrations of genistein in ovariectomized rats

Administration of the isoflavone genistein (GEN) has been described to result in bone protection but also to induce uterotrophic responses. To compare bone protective effects of GEN with an isoflavone-rich diet (IRD) and to further elucidate molecular mechanisms involved in bone-protection, ovariectomized rats (OVX) received either a diet low in isoflavone content (IDD) enriched with GEN (42 mg kg⁻¹ b.wt d⁻¹) (GEN^d), an IRD (14 mg kg⁻¹ b.wt d⁻¹ GEN, 14 mg kg⁻¹ b.wt d⁻¹ daidzein) or were treated subcutaneously (s.c.) with GEN (10 mg kg⁻¹ b.wt d⁻¹) (GEN^sc) for 12 weeks. Intact (SHAM), vehicle treated OVX animals and those substituted with 17β-estradiol (2 μg kg⁻¹ b.wt d⁻¹) (E₂), served as controls.     

Adverse effects of bisphosphonates: current issues

Four bisphosphonates are used for the treatment of metastatic bone disease: clodronate, which is available outside the United States in both intravenous and oral formulations; intravenous pamidronate; intravenous zoledronic acid; and ibandronate, which is also available in intravenous and oral forms. Since the use of bisphosphonates in patients with cancer is palliative, their impact on patients' quality of life and their adverse-effect profiles are essential considerations for effective patient management. The most common adverse effects associated with bisphosphonates are renal toxicity, acute-phase reactions, gastrointestinal (GI) toxicity, and osteonecrosis of the jaw (ONJ). The incidence of these adverse events varies significantly between bisphosphonates. Renal toxicity is a potentially life-threatening event reported in studies of zoledronic acid and, to a lesser extent, pamidronate. In contrast, the renal safety profile of intravenous ibandronate and oral bisphosphonates is similar to that of placebo. Acute-phase reactions occur only with intravenous aminobisphosphonates and may be more common with zoledronic acid. Gastrointestinal effects occur only with oral agents (clodronate and ibandronate) and may be avoided by adhering to dosing instructions. More recently, ONJ has recently emerged as a complication of bisphosphonate use. However, its true incidence is not yet known. The potential adverse effects of bisphosphonates should be considered in the context of the individual patient's characteristics and preferences when selecting a bisphosphonate for metastatic bone disease.     

Noradrenaline use is not associated with extubation failure in septic patients

Standard clinical practice recommends minimal doses of vasoactive drugs during weaning of patients from mechanical ventilation. However there are currently no clinical data to inform clinicians about whether the use of noradrenaline during weaning predisposes to weaning failure. The objective of this study was to evaluate whether the necessity of the vasopressor noradrenaline in mechanically ventilated patients recovering from septic shock changed the extubation outcome. A total of 656 patients recovering from septic shock on mechanical ventilation were selected from intensive care units in two university hospitals. Patients receiving noradrenaline at the time of weaning and case-controls not taking noradrenaline were matched for age, gender, haemodynamic and ventilatory parameters, aetiology of respiratory failure and APACHE II score. One hundred and forty-five patients who successfully tolerated a spontaneous breathing trial were extubated while on noradrenaline therapy and the reintubation rate was measured. In the noradrenaline group, the mean dose of noradrenaline during initial shock treatment was 0.52+/-0.29 microg/kg/min and 0.12+/-0.10 microg/kg/min during weaning. The reintubation rate was 12/63 (19%) in the noradrenaline group and 15/82 (18.3%) in the control group (P=1.00). Intensive care unit mortality was also similar in both groups (10/63, 15.9%) for noradrenaline patients and (11/82, 13.4%) for control patients (P=0.81). Arterial blood gases and ventilatory and haemodynamic parameters were similar in all patients regardless of weaning success. We did not find that the use of noradrenaline at the time of weaning was associated with extubation failure. Low doses of noradrenaline may not preclude weaning from mechanical ventilation.     

Reliable and sensitive analysis of occult bone marrow metastases using automated cellular imaging.

The presence of occult bone marrow metastases (OM) has been reported to represent an important prognostic indicator for patients with operable breast cancer and other malignancies. Assaying for OM most commonly involves labor-intensive manual microscopic analysis. The present report examines the performance of a recently developed automated cellular image analysis system (ACIS; ChromaVision Medical Systems, Inc.) for identifying and enumerating OM in human breast cancer specimens. OM analysis was performed after immunocytochemical staining. Specimens used in this study consisted of normal bone marrow (n = 10), bone marrow spiked with carcinoma cells (n = 20), and bone marrow obtained from breast cancer patients (n = 39). The reproducibility of ACIS-assisted analysis for tumor cell detection was examined by having a pathologist evaluate montage images generated from multiple ACIS runs of five specimens. Independent ACIS-assisted analysis resulted in the detection of an identical number of tumor cells for each specimen in all instrument runs. Additional studies were performed to analyze OM from 39 breast cancer patients with two pathologists performing parallel analysis using either manual microscopy or ACIS-assisted analysis. In 17 of the 39 cases (44%), specimens were classified by the pathologist as positive for tumor cells after ACIS-assisted analysis, whereas the same pathologist failed to identify tumor cells on the same slides after analysis by manual microscopy. These studies indicate that the ACIS-assisted analysis provides excellent sensitivity and reproducibility for OM detection, relative to manual microscopy. Such performance may enable an improved approach for disease staging and stratifying patients for therapeutic intervention.     

Detection of tumor cells in bone marrow of patients with primary breast cancer: a prognostic factor for distant metastasis.

PURPOSE: At the time of primary surgery, approximately 90% of all patients with breast cancer are free of metastases, but in the next 5 years almost 50% of them will relapse. We evaluated the significance of the presence of tumor cells in bone marrow of patients with primary breast cancer to investigate their predictive value for relapse. PATIENTS AND METHODS: Two hundred sixty patients with primary breast cancer were examined for tumor cells in bone marrow aspirates taken from six sites of the skeleton. After density centrifugation, cells in interphase were smeared and stained. For the immunocytologic reaction, we used a new monoclonal antibody (2E11) that was reactive with the core protein of the tumor-associated glycoprotein TAG12. TAG12 is secreted by nearly all human breast carcinomas. RESULTS: A significant correlation was found between tumor-cell detection and tumor stage (P < .0001), nodal status (P < .0001), and tumor grading (P = .002). A good relation to progesterone receptor (PR; P = .008) was found, but there was no correlation to estrogen receptor (ER) and menopausal status. Follow-up examinations showed distant metastases in 26 of 211 patients (15%). Twenty-two relapses occurred among the 81 patients with 2E11-positive cells in bone marrow, but only four occurred among the 130 patients without tumor-cell detection. CONCLUSIONS: This study suggests that tumor-cell detection in bone marrow of patients with primary breast carcinoma is a good predictor for all distant relapses (P < .0005, Cox multiple regression analysis) and provides additional information in regard to other prognostic factors. The highest predicting value for distant metastasis results from the combination of nodal status, negative PR, and tumor-cell presence in bone marrow.     

Rapid mobilization of hematopoietic progenitor cells in rhesus monkeys by a single intravenous injection of interleukin-8

Interleukin-8 (IL-8) is a chemoattractant cytokine involved in chemotaxis and activation of neutrophils. Because in vivo administration of IL-8 induces mobilization of hematopoietic stem cells in mice, we assessed the mobilizing properties of IL-8 in rhesus monkeys. Recombinant human IL-8 was administered as a single intravenous injection at doses of 10, 30, and 100 micrograms/kg to rhesus monkeys (age, 2 to 3 years; weight, 2.5 to 4.5 kg). Venous blood samples were obtained at time intervals ranging from 1 to 480 minutes after IL-8 administration. Cell counts, colony-forming unit-Mix assays, and fluorescence-activated cell sorter analysis were performed. Plasma was harvested to assess IL-8 levels. A time-controlled bolus intravenous injection of 100 micrograms IL-8 per kilogram of body weight resulted in peak IL-8 plasma levels up to 5 micrograms/mL. The calculated half-time life of free IL-8 was 9.9 +/- 2.2 minutes. IL-8 injection resulted in instant neutropenia that was due to pulmonary sequestration, as shown using 99mTc-labeled leukocytes. Within 30 minutes after IL-8 injection, neutrophilia developed with counts up to 10-fold greater than baseline levels. The numbers of hematopoietic progenitor cells (HPCs) increased from 45 +/- 48/mL to 1,382 +/- 599/mL of blood at 30 minutes after injection of 100 micrograms IL-8 per kilogram of bodyweight (mean +/- SD, n = 8). Individual animals showed 10- to 100-fold increase in numbers of circulating HPCs that returned to almost pretreatment values (92 +/- 52 CFU/mL) at 240 minutes after the injection of IL-8. Immunophenotyping showed no significant changes in lymphocyte (sub)populations. A second bolus injection of IL-8 with an interval of 72 hours resulted in similar numbers of mobilized stem cells as observed after the first injection, showing that no tachyphylaxis had occurred. We conclude that IL-8 induces mobilization of HPCs from the bone marrow of rhesus monkeys in a rapid and reproducible fashion. Therefore, IL-8 may be a potentially useful cytokine in the setting of blood stem cell transplantation.     

Comparative effectiveness research across two spine registries

Background

Comparative effectiveness research in spine surgery is still a rarity. In this study, pain alleviation and quality of life (QoL) improvement after lumbar total disc arthroplasty (TDA) and anterior lumbar interbody fusion (ALIF) were anonymously compared by surgeon and implant.

Methods

A total of 534 monosegmental TDAs from the SWISSspine registry were analyzed. Mean age was 42 years (19–65 years), 59 % were females. Fifty cases with ALIF were documented in the international Spine Tango registry and used as concurrent comparator group for the pain analysis. Mean age was 46 years (21–69 years), 78 % were females. The average follow-up time in both samples was 1 year. Comparison of back/leg pain alleviation and QoL improvement was performed. Unadjusted and adjusted probabilities for achievement of minimum clinically relevant improvements of 18 VAS points or 0.25 EQ-5D points were calculated for each surgeon.

Results

Mean preoperative back pain decreased from 69 to 30 points at 1 year (ØΔ 39pts) after TDA, and from 66 to 27 points after ALIF (ØΔ 39pts). Mean preoperative QoL improved from 0.34 to 0.74 points at 1 year (ØΔ 0.40pts). There were surgeons with better patient selection, indicated by lower adjusted probabilities reflecting worsening of outcomes if they had treated an average patient sample. ALIF had similar pain alleviation than TDA.

Conclusions

Pain alleviation after TDA and ALIF was similar. Differences in surgeon’s patient selection based on pain and QoL were revealed. Some surgeons seem to miss the full therapeutic potential of TDA by selecting patients with lower symptom severity.     

Activation and increased expression of adhesion molecules on peripheral blood lymphocytes is a mechanism for the immediate lymphocytopenia after administration of OKT3

We investigated the mechanism by which antihuman CD3 monoclonal antibodies of the isotypes IgG2a (eg, OKT3) and IgA (eg, IXA) can induce the rapid disappearance of virtually all circulating T lymphocytes. We hypothesize that upregulation of adhesion molecules on the lymphocyte membrane contributes to this effect. However, this hypothesis is difficult to test, because of the inherent lymphocytopenia and/or shifts in lymphocyte populations between intra and extra-vascular compartments. Therefore, studies in vitro were performed, as well. Analysis of peripheral blood lymphocytes isolated at several times after addition of OKT3 or IXA to whole blood of healthy individuals showed an immediate increase in the proportion of T cells expressing NKI-L16, an activation epitope on CD11a/CD18. Likewise, an increase in CD11b/CD18 expression occurred. In parallel experiments, a transiently increased adhesion of T cells to endothelial cell monolayers was observed. This adhesion could be completely blocked by anti-CD18 or anti-CD11a monoclonal antibodies and only partly by an anti-CD11b antibody. Our data indicate that upregulation of activation epitopes of CD11a/CD18, as well as increased expression of CD11b/CD18 on T lymphocytes, may result in increased adhesion of these cells to intercellular adhesion molecule-1 (ICAM-1) and ICAM-2 on vascular endothelium. This phenomenon may, at least, partly explain the rapidly occurring peripheral lymphocytopenia observed in vivo.