Efficacy of amodiaquine for uncomplicated Plasmodium falciparum malaria in Harper,Liberia

In the face of spreading chloroquine and sulfadoxine-pyrimethamine (SP) resistance, amodiaquine remains a cheap and efficacious alternative for treating uncomplicated Plasmodium falciparum malaria in many settings. In Harper, south-eastern Liberia, a previous study we conducted showed very high levels of resistance to both chloroquine and SP. In 2001, in an effort to look for possible alternatives, we measured in the same setting the efficacy of amodiaquine in a 28-d study in vivo, with results corrected by polymerase chain reaction genotyping to distinguish recrudescences from reinfections. In total, 107 children were included in the study and received a 3-d supervised course of 25 mg/kg amodiaquine. Of these, 81 were analysable at day 28. The overall failure rate was 19.8% (95% CI 11.7-30.1%) considering both parasitological and clinical outcomes. These results provide hitherto missing data on amodiaquine in Liberia, and confirm that the drug may still be efficacious in settings where chloroquine and SP are failing. We recommend the introduction of amodiaquine in association with artesunate as a first-line antimalarial in Harper.     

Beta-adrenergic and arachidonic acid-mediated growth regulation of human breast cancer cell lines

Adenocarcinoma of the mammary gland is the leading type of cancer in women. Among these breast cancers those that are estrogen-responsive respond well to existing therapeutic regimens while estrogen non-responsive cancers metastasize widely, demonstrate a high relapse rate, and respond poorly to therapy. Over-expression of the arachidonic acid-metabolizing enzymes cyclooxygenase-2 and lypoxygenases is frequently observed in breast cancer, particularly the non-estrogen-responsive type, suggesting a role of the arachidonic acid (AA) cascade in the growth regulation of these malignancies. Adenocarcinomas of the lungs, pancreas and colon also frequently over-express AA-metabolizing enzymes, and recent evidence suggests that the growth-regulating AA-cascade in these malignancies is under beta-adrenergic control. Our current experiments have therefore tested the hypothesis that in analogy to these findings adenocarcinomas of the breast are also regulated by beta-adrenergic receptors via stimulation of the AA-cascade. Analysis of DNA synthesis by [3H]-thymidine incorporation assays in three estrogen-responsive and three estrogen non-responsive cell lines derived from human breast cancers demonstrated a significant reduction in DNA synthesis by beta-blockers and inhibitors of cyclooxygenase or lipoxygenases in all cell lines. Analysis of AA-release in one of the most responsive cell lines demonstrated a time-dependent increase in AA-release in response to the beta-adrenergic agonist isoproterenol. Analysis by RT-PCR revealed expression of beta2-adrenergic receptors in all cell lines whereas beta1-adrenergic receptors were not found in two of the estrogen non-responsive cell lines. Our data suggest that a significant subset of human breast cancers is under control of beta-adrenergic receptors via stimulation of the AA-cascade. These findings open up novel avenues for the prevention and clinical management of breast cancer, particularly the non-estrogen-responsive types. Moreover, our findings suggest that cardiovascular disease and adenocarcinomas in a variety of organ systems, including the breast may share common risk factors and benefit from similar preventive and treatment strategies.     

99mTc-MIBI SPET in non-small cell lung cancer in relationship with Pgp and prognosis

Higher technetium-99m methoxyisobutylisonitrile (MIBI) uptake in non-small cell lung cancer (NSCLC) has been reported to be associated with a positive response to chemotherapy. It has previously been found that in tumour cells, P-glycoprotein (Pgp) expression is of importance for tracer uptake. However, some studies have indicated that Pgp expression does not play an important role in (99m)Tc-MIBI uptake in NSCLC; indeed, a negative correlation between (99m)Tc-MIBI uptake and Pgp expression has been reported. Against the background of conflicting results, our aim was to evaluate the relationship between (99m)Tc-MIBI uptake, prognosis and Pgp expression in NSCLC. A total of 37 patients with NSCLC underwent (99m)Tc-MIBI single-photon emission tomography (SPET) before chemotherapy. In 19 patients both Pgp and p53 expression, and in two patients only p53 expression (due to the limited biopsy material), were measured with immunohistochemical staining. (99m)Tc-MIBI uptake was significantly higher in responders than in non-responders: 3.09+/-1.14 vs 2.24+/-0.88 ( P<0.03) and 3.09+/-1.08 vs 2.37+/-1.06 ( P<0.05) for the early ratio (ER) and the delayed ratio (DR), respectively. The wash-out rate (WR) of responders was not significantly different from that of non-responders. We found no significant differences in ER, DR and WR among the groups positive or negative for Pgp and p53 status. There was a significant positive correlation between the survival rate and both ER and DR: r=0.49 ( P=0.003) and r=0.40 ( P=0.018), respectively. Patients with ER and DR values above 3 showed significantly longer survival than those with values below 3: 14.7+/-8.5 months vs 7.3+/-5.1 months ( P<0.009) and 13.2+/-8.4 months vs 7.4+/-5.3 months ( P<0.04) for ER and DR, respectively. However, interestingly, and in contrast to expectations, patients with a Pgp score of +2 showed significantly longer survival (12.9+/-6.7 months) than those with Pgp scores of +1 (4.4+/-3.0 months) or - (negative) (3.8+/-2.2 months) ( P<0.009 and P<0.02, respectively). Our results suggest that in NSCLC, patients with higher (99m)Tc-MIBI uptake tend to show a positive response to chemotherapy, and patients with ER and DR values above 3 have a significantly better prognosis. We also found that Pgp expression seems to play only a minor role in (99m)Tc-MIBI uptake. Our finding that patients with ER and DR values above 3 have a better prognosis needs to be confirmed in larger series of patients.     

Cooperative actions of hepatocyte growth factor and 1,25-dihydroxyvitamin D3 in osteoblastic differentiation of human vertebral bone marrow stromal cells

Bone formation and remodeling require continuous generation of osteoprogenitor cells from bone marrow stromal cells (MSC), which generate and respond to a variety of growth factors with putative roles in hematopoiesis and mesenchymal differentiation. In this study we examine the interaction of two such factors on the maturation of skeletal components. We previously reported that these factors, hepatocyte growth factor (HGF) and 1,25-dihydroxyvitamin D(3) (vitD(3)), act together to increase alkaline phosphatase in chondroblasts. We now describe the cooperative effect of these agents on MSC isolated and cultured from human vertebral bone marrow. MSC (passages 3-9) isolated from bone marrow cells of human vertebrae (T1-L5) from 22-36-year-old normal donors were first expanded in vitro and then plated in the presence or absence of 10 ng/mL HGF and/or 10 nmol/L vitD(3), for 7-18 days. HGF treatment increased cell proliferation 2.5-fold, with no effect on alkaline phosphatase activity. Whereas vitD(3) treatment inhibited cell growth by 50%, alkaline phosphatase activity was stimulated eightfold, although no mineralization was observed. HGF together with vitD(3) increased cell proliferation 1.5-fold and alkaline phosphatase activity 13-fold over untreated control. Moreover, mineralization was detected only with this combination. Our findings provide evidence that HGF in concert with vitamin D may promote growth and differentiation of human MSC into osteogenic cells.     

Use of topical misoprostol to reduce radiation‐induced mucositis: Results of a randomized,double‐blind,placebo‐controlled trial

Radiation‐induced mucositis is an acute reaction of the mucosa of patients undergoing head and neck radiotherapy. It can have debilitating and dose‐limiting consequences. There is no consensus on an accepted intervention that significantly reduces its severity. Misoprostol is a synthetic prostaglandin E₁ analogue, with properties of a mucosal cytoprotectant. We designed a randomized, double‐blind, placebo‐controlled trial of misoprostol in patients with head and neck cancer. The aim of this study was to determine if topical misoprostol was effective in reducing the severity of radiation‐induced mucositis in patients receiving radical dose radiotherapy. The effect of this intervention on a patient’s general well‐being was also investigated. The primary end‐point of the study was the incidence of Radiation Therapy Oncology Group grade 3 mucositis. Between 1999 and 2002, 83 patients were recruited into the study at Westmead and Nepean Hospitals, Sydney. Forty‐two patients were randomized to receive misoprostol and 41 to receive a placebo. Most patients received radiotherapy in the adjuvant setting (52 of the 83) and had either an oral cavity (42 of the 83) or an oropharyngeal (16 of the 83) cancer. We could not identify any significant difference in the incidence of severe mucositis based on whether patients were allocated to receive misoprostol or placebo. There was no significant difference in the mean area under the mucositis curve (13.2 vs 16.6; P = 0.1). Patients allocated to misoprostol did report slightly increased soreness (7.6 vs 6.9; P = 0.04) and a greater use of analgesics. However, this difference did not translate into a worse feeling of general well‐being as measured by a simple visual analogue scale (5.8 vs 5.2; P = 0.3). In conclusion, we were unable to identify a reduction in radiation‐induced mucositis in patients receiving misoprostol. There is a paucity of high‐level evidence on potentially useful interventions and a continued need for new and innovative research, incorporating quality‐of‐life measurements, in patients experiencing radiation‐induced mucositis.     

Parotid lymph‐node metastases from cutaneous squamous‐cell carcinomas: Treatment outcome and prognostic factors following surgery and adjuvant radiotherapy

Australia has the highest incidence of cutaneous squamous cell carcinoma (SCC) in the world. The majority of lesions occur in the head and neck, and regional lymph‐node metastases from cutaneous SCCs, though uncommon, reflect an aggressive manifestation. Surgery and adjuvant radiotherapy are currently considered best practice. Fifty‐two eligible patients during 1980–1997 were identified in a retrospective review of patients treated within the department of Radiation Oncology, Westmead Hospital, Sydney. Relevant data were extracted from the files, referring clinicians and the New South Wales Cancer Council. The median age at diagnosis was 63 years and the majority were men (87%). Unfavourable pathological features were present in many of the patients. Only extranodal spread (P = 0.02) was identified as an independent predictor for locoregional recurrence on multivariate analysis. The cumulative locoregional recurrence rates were 28 and 45% at 2 and 5 years, respectively. The 5‐year cause‐specific survival rate in this study was 65%. We conclude that parotid lymph‐node metastases from cutaneous SCCs of the head and neck are associated with a high rate of locoregional recurrence and cause‐specific mortality despite surgery and adjuvant radiotherapy. The role of altered fractionation after surgery as a means to further enhance locoregional control warrants further investigation.     

Posterior stabilisation of a malignant cervico-thoracic vertebral bone defect

Oesophageal cancer is frequently complicated by malignant fistulae. Necrosis of the tumour following radiotherapy or chemotherapy may lead to the development of fistulae between the oesophagus and adjacent tissues and organs. We report the expansion of an extra-luminal oesophageal cancer after resection, invading the cervico-thoracic spine, fortunately without neurological deficit, and leading to instability and formation of a malignant fistula linking the tracheo-bronchial tree to the subarachnoidal space. To prevent imminent paraplegia and to alleviate severe pain, we rigidly stabilised the spine at the cervico-thoracic junction using an angle-stable system through a single posterior approach. Further postoperative follow-up revealed no signs of neurological deterioration. Cervico-thoracic stability was preserved until the patient died nearly five months postoperatively. This case shows that posterior stabilisation and decompression may be a palliative option for patients with imminent paraplegia and severe pain due to advanced tumour infiltration of the cervico-thoracic spine.     

Vertebroplasty--basic science, indications and technique

INTRODUCTION: Vertebroplasty is a relatively new procedure for the treatment of vertebral body fractures of different origin. Due to early promising results the rate of performed procedures increases constantly. Indeed an increasing number of partially severe complications are reported. A summary of the existing findings seems therefore necessary. METHODS: On the basis of a medline inquiry important aspects of vertebroplasty in the fields of basic science, diagnostics, indications, contraindications, technique, results and complications were compiled. RESULTS: Especially for the field of indications, possible longterm effects and for the "ideal" technique open questions exist, mainly due to missing prospective, randomized long-term clinical trials. CONCLUSIONS: A final assessment of the significance of vertebroplasty for osteoporotic fractures in comparison to conservative treatment is actually not possible. In contrast vertebroplasty is a therapeutical option for malignomas in selected cases.