Bleeding events in bevacizumab-treated cancer patients who received full-dose anticoagulation and remained on study.

BACKGROUND: Bevacizumab provides clinical benefit in multiple solid tumours, but is associated with some increase in bleeding risk. Thrombotic events necessitating therapeutic anticoagulation (TA) are common in cancer. This report describes the safety of concurrent bevacizumab and TA in three large placebo-controlled clinical studies. METHODS: Study 1 (metastatic colorectal cancer (mCRC)), study 2 (mCRC), and study 3 (advanced non-small cell lung cancer) were blinded phase III studies. Eligibility criteria excluded patients on TA. Patients on protocol treatment who developed thrombotic events requiring TA were permitted to continue bevacizumab or placebo under specified conditions. Adverse events in patients who received bevacizumab and TA concurrently were assessed using the NCI-CTCAE scale. RESULTS: While experience is limited, venous thrombotic events were the most common reason for TA initiation in the three studies. Severe bleeding event rates for patients receiving TA in the bevacizumab-treated groups were similar in frequency to the placebo groups, ranging from 0 to 8% or 0 to 67 events per 100 patient-years. No severe pulmonary bleeding was reported in any of the TA-treated populations. CONCLUSIONS: These data suggest that bevacizumab did not increase the risk of severe bleeding in cancer patients who received TA.

Activation of Raf-1 and mitogen-activated protein kinase in murine macrophages partially mimics lipopolysaccharide-induced signaling events.

Lipopolysaccharide (LPS), a highly conserved component of the outer membrane of gram-negative bacteria, stimulates macrophages to release various cytokine and eicosanoid mediators of the immune response. The mechanism by which LPS stimulates these cells is poorly characterized. One of the most rapid LPS-stimulated events is the phosphorylation and activation of the p42 and p44 isoforms of mitogen-activated protein (MAP) kinase. We wished to examine the role of MAP kinase in LPS-induced signaling in murine macrophages by activating MAP kinase independently of LPS. An expression vector encoding a Raf-1:estrogen receptor (ER) chimeric protein was transfected into the murine macrophage cell line RAW 264.7. Activation of this chimeric protein (delta Raf-1:ER) by estradiol resulted in rapid and prolonged activation of MAP kinase, as expected from previous results implicating Raf-1 as an upstream activator of this signaling cascade. LPS stimulation induced accumulation of MAP kinase phosphatase 1 messenger RNA, whereas delta Raf-1:ER activation did not, perhaps accounting for the more prolonged activation of MAP kinase seen in response to delta Raf-1:ER activation. Similarly, activation of DNA binding by the transcription factor, nuclear factor (NF) kappa B, as assessed by electrophoretic mobility shift assay, occurred in response to LPS stimulation but not in response to delta Raf-1:ER activation or phorbol myristate acetate (PMA) stimulation. Using an enzyme-linked immunosorbent assay for murine tumor necrosis factor alpha (TNF-alpha), we found that LPS and PMA stimulation and delta Raf-1:ER activation induced secretion of TNF-alpha, although the amount of TNF-alpha secreted in response to delta Raf-1:ER activation and PMA stimulation was approximately 20-fold less than that secreted in response to LPS. Correspondingly, accumulation of TNF-alpha messenger RNA was weakly induced by delta Raf-1:ER activation or PMA stimulation, whereas strong induction was noted in response to LPS. These results suggest that Raf-1 or PMA activation of MAP kinase in murine macrophages is sufficient for a small amount of TNF-alpha production and secretion in the absence of NF-kappa B activation, but LPS stimulation involves additional signaling events, such as NF-kappa B activation, that augment the response seen with activation of MAP kinase alone.

Predictors of the post-thrombotic syndrome during long-term treatment of proximal deep vein thrombosis.

BACKGROUND: The post-thrombotic syndrome is a chronic, poorly understood complication of deep venous thrombosis (DVT). OBJECTIVES: To evaluate predictors of the post-thrombotic syndrome, including intensity of long-term anticoagulation, and to assess the impact of the post-thrombotic syndrome on quality of life. PATIENTS AND METHODS: The setting was 13 Canadian hospitals and one US hospital. One hundred and forty-five patients with an unprovoked episode of proximal DVT who were initially treated with 3 months of conventional-intensity warfarin [target International Normalized Ratio (INR) of 2.5] then participated in a trial comparing two intensities of long-term warfarin therapy (target INR 2.5 vs. INR 1.7). Post-thrombotic syndrome was assessed at the end of the trial using a validated clinical scale. Generic and venous disease-specific quality of life was compared in patients with and without the post-thrombotic syndrome. Multivariable regression analyses were performed to identify predictors of the post-thrombotic syndrome and of its severity. RESULTS: After an average follow-up of 2.2 years, the prevalence of post-thrombotic syndrome was 37% and of severe post-thrombotic syndrome was 4%. Quality of life was worse in patients with the post-thrombotic syndrome compared with patients who did not have it. The presence of factor (F)V Leiden or the prothrombin gene mutation was an independent predictor of both a lower risk (P = 0.006) and reduced severity (P = 0.045) of the post-thrombotic syndrome. Intensity of anticoagulation did not influence the risk of developing the post-thrombotic syndrome. CONCLUSIONS: The post-thrombotic syndrome is a frequent and burdensome complication of proximal DVT, even among patients maintained on long-term oral anticoagulation. While the presence of FV Leiden or prothrombin gene mutation appears to be associated with a reduced risk of post-thrombotic syndrome, this finding requires further evaluation in prospective studies.

Advances in the treatment of von Willebrand disease.

Von Willebrand disease (VWD) is the most commonly inherited bleeding disorder, caused by inheritance of a quantitative or qualitative abnormality of von Willebrand factor (VWF). While the majority of patients with VWD are successfully treated with adjunctive therapies or with the synthetic vasopressin analog desmopressin acetate (DDAVP), a subset of patients requires replacement therapy. In the past, cryoprecipitate was the mainstay of therapy; however, it was associated with seroconversion to hepatitis B (HBV), hepatitis C (HCV), and the human immunodeficiency virus (HIV) in treated individuals. With the advent of virucidal methodology and, more recently, nucleic acid testing (NAT) of plasma fractions, the plasma-derived concentrates containing VWF are now considered the therapeutic standard of care.

Culture surfaces coated with various implant materials affect chondrocyte growth and metabolism.

The effect on chondrocyte metabolism of culture surfaces sputter-coated with various materials used for orthopaedic implants was studied and correlated with the stage of cartilage cell maturation. Confluent, fourth-passage chondrocytes from the costochondral resting zone and growth zone of rats were cultured for 6 or 9 days on 24-well plates sputter-coated with ultrathin films of titanium, titanium dioxide, aluminum oxide, zirconium oxide, and calcium phosphate (1.67:1). Corona-discharged tissue culture plastic served as the control. The effect of surface material was examined with regard to cell morphology; cell proliferation (cell number) and DNA synthesis ([3H]thymidine incorporation); RNA synthesis ([3H]uridine incorporation); collagenase-digestible protein, noncollagenase-digestible protein, and percentage of collagen production; and alkaline phosphatase-specific activity, both in the cell layer and in trypsinized chondrocytes. Cell morphology was dependent on surface material; only cells cultured on titanium had an appearance similar to that of cells cultured on plastic. While titanium or titanium dioxide surfaces had no effect on cell number or [3H]thymidine incorporation, aluminum oxide, calcium phosphate, and zirconium oxide surfaces inhibited both parameters. Cells cultured on aluminum oxide, calcium phosphate, zirconium oxide, and titanium dioxide exhibited decreased collagenase-digestible protein, noncollagenase-digestible protein, and percentage of collagen production, but [3H]uridine incorporation was decreased only in those chondrocytes cultured on aluminum oxide, calcium phosphate, or zirconium oxide. Chondrocytes cultured on titanium had greater alkaline phosphatase-specific activity than did cells cultured on plastic, but the incorporation of [3H]uridine and production of collagenase-digestible protein, noncollagenase-digestible protein, and percentage of collagen was comparable. The response of chondrocytes from the growth zone and resting zone to culture surface was comparable, differing primarily in magnitude. Cell maturation-dependent effects were evident when enzyme activity in trypsinized and scraped cells was compared. These results indicate that different surface materials affect chondrocyte metabolism and phenotypic expression in vitro and suggest that implant materials may modulate the phenotypic expression of cells in vivo.

Hematologic complications of HIV infection.

Hematologic complications of HIV disease are commonly encountered by physicians and other health-care workers caring for patients infected with this virus. Ineffective hematopoiesis, infiltrative diseases of the bone marrow, nutritional deficiencies, peripheral destruction of blood cells secondary to splenomegaly or immune dysregulation, and drug effects all contribute to the variety of hematologic abnormalities seen in these patients. This review explores the causes of isolated or trilineage cytopenias and coagulopathies; the utility of bone marrow biopsy examination; and the role of colony-stimulating factors as therapeutic agents in patients with HIV disease.

Proteinuria after burn injury.

Qualitative and quantitative aspects of the excretion of protein after burn injury have been investigated. The excretion of total protein and of albumin have been measured nephelometrically while the excretion of proteins of both serum and non-serum origin have been measured by immunoelectrophoresis using antiserum against serum proteins or against a pool of urine from burned patients. Comparison of the patterns of proteins observed in urine using these two different antisera showed the presence of at least three major proteins that did not originate from the plasma. The excretion of two of these three proteins followed closely the pattern of total protein excretion which reached a maximum at five to seven days after injury. The excretion of albumin was greatest in the first 48 hours after injury. Examination of the original burn patients' urine antigen by sodium dodecyl sulphate polyacrylamide gel electrophoresis showed that this urine pool contained greater amounts of lower molecular weight proteins than were observed in a pool of normal urines. The observations suggest that a biphasic renal pathophysiology is observed after burn injury. Initially, there develops a mild transient glomerular lesion which progresses to a different state which shows at least some of the features of a tubular proteinuria.

A novel lacI transgenic mutation-detection system and its application to establish baseline mutation frequencies in the scid mouse.

To assess DNA mutations in vivo, we have established a new transgenic mouse line, BC-1, carrying a lacI target gene for mutation detection within a bacteriophage shuttle-vector. The lacI gene was positioned within sequences derived from a rearranged murine immunoglobulin gene locus, a feature that distinguishes the BC-1 transgene from other shuttle vector systems. As mutations in lacI transgenes likely reflect mutations occurring throughout the genome, these systems have been successfully used to investigate spontaneous and induced mutations in a variety of tissues. An important additional application of the transgenic systems is the characterization of lacI mutations occurring in murine strains having specific DNA repair defects. For this study, scid (severe combined immunodeficiency) mice were selected as animals with this mutation have a defect in double-strand DNA break repair. To determine what impact the scid mutation might have on spontaneous mutation frequencies within DNA recovered from various tissues, these mice were crossed with the BC-1 line. Interestingly, mutation frequencies within BC-1/scid mouse DNA were not significantly different from those of BC-1 control mice. Furthermore, spontaneous lacI mutations obtained from BC-1 and from BC-1/scid liver DNA were similar in spectrum. As spontaneous BC-1 liver mutations were similar to those reported previously for other lacI systems, such as the Big Blue transgenic line, this suggested that the nature of the DNA sequences flanking the reporter gene did not modify lacI mutation rate or character.

Tumor necrosis factor-alpha and interleukin-8 release from U937 human mononuclear cells exposed to zinc oxide in vitro. Mechanistic implications for metal fume fever.

Respiratory exposure to zinc oxide results in metal fume fever, a flu-like illness characterized by dose-dependent increases in pulmonary tumor necrosis factor-alpha (TNF) and interleukin-8 (IL-8). To examine whether mononuclear cells are a source of these proinflammatory cytokines, we exposed U937 cells to zinc oxide in vitro. Cell culture supernatant TNF and IL-8 was measured after 3, 8, and 24 hours of exposure to zinc oxide in varying concentrations. Zinc oxide exposure in vitro led to TNF release in a dose-dependent manner at 3, 8, and 24 hours (analysis of variance [ANOVA] P = 0.0001). IL-8 demonstrated a statistically significant zinc exposure response at 8 hours (ANOVA P = 0.005) and 24 hours (ANOVA P = 0.02). IL-8 at 8 hours correlated with 3-hour TNF levels (r = 0.52, P = 0.04). These data demonstrate that in vitro zinc oxide exposure stimulates U937 mononuclear cells to release TNF and IL-8 consistent with in vivo observations in metal fume fever.

Thermal damage to skin collagen.

The effect of temperature upon the solubility of frozen skin collagen in vitro and its susceptibility to digestion by proteolytic enzymes has been studied. Both of these parameters are increased with temperature. Above 52 degrees C there is a sudden increase in both the solubility of collagen and its susceptibility to digestion, suggesting that this temperature is associated with changes in the structure of the skin collagen. This increase in susceptibility to digestion may have an influence upon the nature of the healing process in the burn wound.

The progress of hypertrophic scars monitored by ultrasound measurements of thickness.

Ultrasound scanning was used to measure the thickness of hypertrophic scars following burn injury. Scarred areas on patients receiving pressure therapy were monitored at regular intervals from the initial healing, through the hypertrophic stage, to maturation of the scars. The data, collected over a period of 30 months, allowed a comparison of scar development in children and adults and a comparison of the response at different anatomical sites. Measurements made on individual patients could be related to factors affecting the progress of their hypertrophic areas and provided a useful backup to visual assessment during pressure garment therapy.

Hemophilic arthropathy: considerations in management.

The authors evaluate nonsurgical and surgical approaches to treating patients with hemophilic arthropathy and review the functional and economic limitations imposed on treating these patients. Indications for surgery are discussed and a case study that incorporates both conservative and surgical management options is presented. While the advent of factor replacement therapy has dramatically changed the course of treatment and prognosis for patients with hemophilia, the authors argue that the economic burden of treating these patients is still very high. The authors recommend that proper conservative and surgical management options for patients with hemophilia should be based upon a thorough understanding of the disease process.

Response of bone and cartilage cells to biomaterials in vivo and in vitro.

In vivo and in vitro models have been developed to study the bone/material interface. The in vivo model exploits the osteogenesis that accompanies marrow ablation of the rat tibia and uses morphological and biochemical changes in extracellular organelles, called matrix vesicles, as markers of the healing process. Matrix vesicles, which are associated with primary bone formation and calcification, are produced by osteoblasts and are sensitive to cellular and environmental regulation. In bone adjacent to bone-bonding implants, matrix vesicle number increases, as does its alkaline phosphatase activity. In bone adjacent to nonbonding materials, matrix vesicle activity is inhibited. The materials exert systemic effects which can also be studied by use of matrix vesicles. Cell models are needed in order for the specificity of the cellular response to the material to be understood. By the use of culture plates sputter-coated with implant materials, the response of cells can be studied under controlled conditions. Comparison of the response of costochondral chondrocytes at two stages of endochondral development demonstrates that the effects of various materials are surface- and cell-maturation-dependent. Cells cultured on Ti exhibited increased alkaline-phosphatase-specific activity, whereas those cultured on Al2O3 have decreased enzyme activity.

Childbirth preparation and outcomes of labor and delivery in primiparous women.

Preparation for childbirth (Lamaze classes) is becoming an increasingly popular addition to patient education. This retrospective study investigates its effect on 64 primiparas in comparison with a control group who had not taken classes. The two groups were matched for age, antenatal risk scores, ethnic derivation, and socioeconomic status. No difference was found in the use of analgesia and anesthesia, the length of labor, type of delivery, incidence of fetal distress, infant birth weights, Apgar scores, or maternal and neonatal complications. However, there was a statistically significant increase in the use of oxytocin for augmentation of labor (P less than 0.01) in the prepared group.

A patient resource program--strengthening primary nursing.

A patient resource program addresses fragmentation of care, duplication and blurred accountability. This centralized referral service uses experts such as clinical nurse specialists, enterostomal therapists and pain management nurses to improve the primary nursing care model.

Patterns of progression in patients with recurrent glioblastoma treated with bevacizumab.

OBJECTIVE: We evaluated patterns of tumor progression in patients with recurrent glioblastoma who were treated with bevacizumab (BEV) alone or in combination with irinotecan (CPT-11) while participating in the BRAIN study. METHODS: An independent neuroradiologist reviewed MRI scans at baseline and progression in patients who received BEV (n = 85) or BEV+CPT-11 (n = 82) while on BRAIN. Tumor patterns were scored as local, distant, diffuse, or multifocal. Median progression-free survival (PFS) and overall survival (OS) were estimated using Kaplan-Meier methods. Hazard ratios for PFS and OS were estimated using a Cox regression model. RESULTS: Twenty-eight percent of patients who participated in BRAIN had nonlocal disease at baseline (72% local disease). Sixty-seven (79%) patients treated with single-agent BEV and 57 (70%) patients treated with BEV+CPT-11 experienced disease progression while on BRAIN. Most patients in each treatment group did not have a change in the radiographic pattern of their tumor (i.e., "no shift") at the time of progression. The proportion of BEV patients with no shift (82%) was greater than that of BEV+CPT-11 patients (53%, χ(2) p = 0.0004), and a greater proportion of BEV+CPT-11 patients (39%) compared with BEV patients (16%) experienced local-to-diffuse tumor pattern at progression (χ(2) p = 0.002). Patients treated with BEV or BEV+CPT-11 who had local-to-local or local-to-diffuse progression patterns had similar efficacy outcomes, including objective response, PFS, and OS. CONCLUSIONS: Most patients treated with BEV or BEV+CPT-11 on BRAIN did not experience a change from baseline in radiographic characteristics of disease at the time of progression.

Diagnosis and incidence of inherited von Willebrand disease.

Von Willebrand disease is the most commonly inherited bleeding disorder, caused by the inheritance of a quantitative or qualitative abnormality of von Willebrand factor. Clinical manifestations of this disorder are diverse, and traditional diagnostic tools vary in sensitivity, specificity, and overall usefulness. However, as more accurate diagnostic testing is developed and implemented, determination of the disease's incidence and prevalence will improve, allowing the identification and treatment of patients who suffer from this disorder.