Colony-forming cell proliferation: a rapid and sensitive assay system for murine granulocyte and macrophage colony-stimulating factors

A microculture assay for murine granulocyte-macrophage colony- stimulating factor (GM-CSF) has been developed using fetal liver GM colony-forming cells (CFC) isolated by fluorescence-activated cell sorting. These GM-CFC are free of mature hemopoietic cells, such as granulocytes and macrophages, which may interfere with direct assays for GM-CSF. The assay procedure allows the quantitation of GM-CSF within 48 hr by measuring the number of cells produced from 50 GM-CFC in microcultures (15 microliter). The assay is particularly simple to set up and score and yet, because of the reduced volumes, this assay is still capable of detecting 0.2 pg (i.e., 0.2 U) of GM-CSF within 48 hr, i.e., 100 times less GM-CSF than the conventional soft agar assay. By allowing the microcultures to develop for 7 days, the extra proliferation allows a further tenfold increase in the sensitivity of CSF detection. The time and cost of setting up hundreds of GM-CSF assays for fractions from chromatographic columns, e.g., reverse phase high performance liquid chromatography, is reduced by at least five- fold. Enough GM-CFC can be isolated and stored frozen in one afternoon to provide sufficient cells for the daily assay of 200 samples of GM- CSF for several months. Microassay results for several sources of GM- CSF at different stages of purification are compared to the results obtained from the soft agar assay.     

Long-term follow-up of patients with giant cell tumor of the sacrum treated with selective arterial embolization

BACKGROUND: Giant cell tumors of the bone can behave as aggressive and sometimes lethal tumors. In the sacrum, the tumor can be extremely difficult to manage. Standard treatments, including surgery and radiation, are associated with significant complications and recurrence rates. The goal of this study is to evaluate the long-term outcome of selective arterial embolization as an alternative treatment modality. METHODS: From 1975 to 2001, 18 patients were treated with selective intraarterial embolization. The embolization method was a combination of Gelfoam particles and coils for peripheral and central occlusions, respectively. The number of embolizations was based on clinical symptoms, radiographic response, and the vascularity of the tumor. Nine patients received intraarterial cisplatin as part of their treatment. The median follow-up was 105 months. RESULTS: Of 18 patients, 14 responded favorably to embolization with improvement in pain and neurologic symptoms. Computed tomographic and magnetic resonance imaging scans showed reossification and stabilization of tumor size. Arteriograms showed diminished vascularity. With long-term follow-up, three patients developed late disease recurrences within the sacrum. Kaplan-Meier analysis showed that the risk of local recurrence is 31% at 10 years and 43% at 15 and 20 years. The long-term outcome was not affected by intraarterial cisplatin. There was one death that occurred 1 day after embolization. CONCLUSIONS: Most patients demonstrate an objective early radiographic response to embolization. Long-term follow-up shows that the response is durable in approximately one half of the patients. Given the potential morbidity of other treatments, embolization should be included in the armamentarium of treatment for this difficult disease. Embolization may be used alone or in conjunction with other therapy. Long-term follow-up is recommended for all patients because late disease recurrence or sarcomatous change can occur.     

Avulsion fracture of the anterior inferior iliac spine with abundant reactive ossification in the soft tissue

 Patients who have sustained an avulsion fracture and present clinically during the healing phase of the injury may manifest a mass that clinically and radiographically mimics a malignant neoplasm. A 15-year-old male soccer goalkeeper presented with a large ossified mass in the soft tissues overlying the right hip 6 months after experiencing a popping sensation in his hip joint during a game. Although an osteosarcoma was suspected clinically and radiographically, a Tru-Cut needle biopsy of the lesion revealed reactive bone formation. Correlation of the clinical, radiographic, and pathologic findings indicated an avulsion fracture of the anterior inferior iliac spine with abundant reactive ossification in the soft tissues. The healing phase of an avulsion fracture may clinically and radiographically be mistaken for neoplasia. In such cases, a Tru-Cut needle biopsy may reveal the reactive nature of the process.     

Orthopaedic metal devices coated with a novel antiseptic dye for the prevention of bacterial infections

Gendine is a novel antiseptic dye with broad-spectrum antimicrobial activity that may be used to coat plastics and metal devices. Our objective was to determine the efficacy of gendine-coated orthopaedic metal devices in preventing methicillin-resistant Staphylococcus aureus (MRSA) colonisation. Stainless steel and titanium Schanz rods were coated with gendine. The zone of inhibition (ZoI) around the rods with and without gamma-irradiation was determined by a modified Kirby-Bauer method. A previously published bioprosthetic biofilm colonisation model, modified Kuhn's method, was used to determine the adherence of MRSA to coated and uncoated rods, with and without irradiation, after insertion into bovine bone and after 3 months shelf life followed by 2 weeks of immersion in serum. The gendine-coated Schanz metal rods showed a net ZoI of 16 mm against MRSA before and after irradiation. Gendine-coated rods showed no biofilm formation (0 colony-forming units (CFU)), which was a significant reduction (P<0.001) compared with uncoated controls (>5000 CFU). Coated rods exposed to high-dose gamma-irradiation and coated rods drilled into bone also showed significant efficacy (P<0.001) in preventing biofilm adherence. After 2 weeks, gendine-coated rods maintained significant durability (P<0.01), resulting in 90% reduction in MRSA biofilm adherence compared with uncoated control rods. Results indicate that gendine-coated metal rods are highly efficacious in the prevention of MRSA biofilm.     

Risk factors for adult-onset asthma: A 14-year longitudinal study

Background and objectives:   Few longitudinal studies have examined the risk factors and natural history of adult-onset asthma. This study assessed the subject characteristics and lifestyle factors that predicted the new diagnosis of asthma in adulthood and how these factors changed over time in those who developed asthma compared with those who do not.
Methods:   The study enrolled 1554 adults from the Busselton Health Study seen in 1981 and again in 1994–1995 who initially reported never having had doctor-diagnosed asthma. Questionnaire measures were used to assess doctor-diagnosed asthma, respiratory history and tobacco smoking. Height, weight and spirometric measures of lung function were measured. Atopy was assessed by skin prick tests. Logistic regression analysis was used to identify risk factors for adult-onset asthma and changes over time.
Results:   Reported wheeze, rhinitis, chronic cough, smoking and lower levels of lung function in 1981 each predicted asthma diagnosis by 1994–1995. Neither initial skin-prick reactivity nor newly positive skin-prick tests at follow up were associated with adult-onset asthma. Those diagnosed with asthma were more likely to have new wheeze, new rhinitis, new habitual snoring, weight gain and excess decline in lung function.
Conclusions:   Adult-onset asthma has risk factors that are distinct from those observed in childhood asthma. The presence of upper airway symptoms including rhinitis, as well as lifestyle factors, such as smoking, predicts those at greatest risk. However, neither pre-existing atopy nor new atopy as measured by skin prick tests was associated with adult-onset asthma.