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NO Effect on Inflammatory Reaction in Extracorporeal Circulation : Ex vivo StudiesLahtinen, Mika January 2005 (has links)
Nitric oxide (NO) is expressed in inflammatory tissues. However, NO effects are controversial in inflammation; NO is described as acting in a dose dependent manner and possess both pro-inflammatory and anti-inflammatory properties. The present thesis explored the role of NO in relation to white blood cell (WBC) and protein system activation by foreign surfaces in simulated extracorporeal circulation (SECC) using human whole blood from volunteer donors. Three doses of NO, 40 ppm, 80 ppm and 500 ppm, were administered and an array of markers of WBC and protein activation were studied. Neutrophil degranulation was detected with myeloperoxidase (MPO), human neutrophil lipocalin (HNL) and lactoferrin (LF); eosinophil degranulation with eosinophil cationic protein (ECP) and eosinophil peroxidase (EPO); and basophil degranulation with histamine. Furthermore, whole blood and WBC capacity to produce reactive oxygen species (ROS) were studied and cytokine release was measured with IL-1 and IL-10. Complement activation was measured with C3a and C5b-9 complex and contact system activation with FXIIa-C1INH, FXIIa-AT, FXIa-C1INH and FXIa-AT. NO increased neutrophil degranulation at all dose levels and 80 ppm NO increased basophil degranulation; whereas, NO exerted no effect on eosinophil degranulation, WBC subset counts, cytokine release or capacity to produce ROS. In addition, while increasing both specific and azurophil degranulation with 40 ppm, 80 ppm and 500 ppm, NO reversed the classical degranulation hierarchy with 500 ppm and azurophil degranulation became predominant. Furthermore, NO effect was greater with 500 ppm than with 80 ppm, indicating a dose response effect. The lack of iNOS mRNA expression in WBC and lack of L-NAME effect on degranulation and nitrite/nitrate production, together with absent increase in nitrite/nitrate in controls, excluded autocrine or paracrine regulation of degranulation. FXIIa-AT and FXIa-AT complexes increased and became predominant during early recirculation, whereas FXIIa-C1INH and FXIa-C1INH complexes were predominant at baseline but remained unaltered, suggesting contact system inhibition predominantly via AT. C3a and C5b-C9 increased. NO had no effect on either contact or complement system activation; however, 500 ppm NO shortened active clotting time. In conclusion, the present data suggest that NO has a direct effect on neutrophil and basophil degranulation. Recognition of NO as an enhancer of degranulation may give access to new therapeutic tools for local and systemic inflammatory therapies; whereas, the identification of increased AT mediated inhibition of FXIIa and unchanged C1INH complexes presents new possibilities for therapeutic intervention in conditions such as hereditary angioedema and heart surgery.
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Low-Density Lipoprotein Oxidation and Renal Dysfunction : New Markers of Poor Prognosis in Patients with Unstable Coronary Artery DiseaseJohnston, Nina January 2006 (has links)
In patients with unstable coronary artery disease (CAD) biochemical markers are emerging as useful tools in clinical management. In this thesis we studied the use of markers of low-density lipoprotein (LDL) oxidation and renal function. Our study populations consisted of unstable CAD patients included in the Fast Revascularisation during Instability in Coronary artery disease (FRISC)-II trial and healthy controls. Patients were followed for 2 years regarding death and myocardial infarction (MI). Using receiver operating characteristic curve analysis, we found that oxidized low-density lipoprotein (OxLDL), especially when combined with high-density lipoprotein, compared to traditionally measured lipids/lipoproteins, and a new lipoprotein marker, lipoprotein associated-phospholipase A2, was better at discriminating between healthy controls and CAD patients. In patients, OxLDL was found to be an independent prognostic marker associated with an increased risk of MI, of particular use in patients with no evidence of myocardial necrosis. In our study on the effects of an early invasive treatment strategy in unstable CAD patients with mild to moderate renal dysfunction (i.e. creatinine clearance <90mL/min) we found that in patients randomized to invasive treatment, the rates of death/MI and MI alone were significantly lower than in patients randomized to non-invasive treatment. In patients treated invasively, no detrimental effects were seen on renal function at follow-up at 6 months. In healthy controls, we investigated new markers of renal (cystatin C) and cardio-renal function (N-terminal probrain natriuretic peptide, [NT-proBNP]) regarding reference levels and physiological determinants. We found that cystatin C is influenced by age whereas NT-proBNP is influenced by age and gender. Our studies suggest that OxLDL and renal dysfunction are associated with a poor prognosis in unstable CAD patients and that these markers demonstrate potential for clinical use. In the search for new markers related to renal function we have contributed with reference levels of cystatin C and NT-proBNP.
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Apoptosis, proliferation, and sex steroid receptors in endometrium and endometrial carcinomaDahmoun, Marju January 2003 (has links)
This thesis focuses on the involvement of apoptosis and proliferation in the mechanisms of menstruation and hormonal replacement therapy, HRT, as well as in the mechanisms of progesterone therapy in endometrial carcinoma. The aim of the first study was to investigate endometrium for 4 days before and for 2 days during menstruation. In the epithelium, rapid increase in the apoptotic index, decreasing expression of estrogen receptor α (ER) and progesterone receptor (PR), and minimal proliferation were observed prior to menstruation. In the stroma, an increase in the expression of ER and PR and proliferation was seen before the final decrease, and increased apoptosis was seen during menstruation. Thus, apoptosis is involved in the remodeling of the endometrium during menstruation. Postmenopausal endometrium showed unaffected homeostasis, i.e. unchanged ratio between apoptotic index and Ki-67 index during substitution therapy. ER expression was decreased both in the epithelium and stroma, while PR showed some increase in receptor expression. The unchanged homeostasis contributes to endometrial safety during combined continuous HRT. Unchanged apoptosis and increasing proliferation were observed with increasing tumor grade in 29 patients with endometrioid endometrial carcinoma, which may contribute to greater aggression as tumor grade increases. Decreased proliferation was observed after medroxy-progesterone at 20 mg per day particularly in the foci of maximal proliferation in G1 and G2 tumors. The expression of ER was unchanged, while PR was decreased in the foci of maximal expression for PR in G1 and G2 tumors. Since high proliferation and PR expression also coexisted in the same foci, evaluated in G1 and G2 tumors, the effect of progesterone could be facilitated in these tumor groups. High expression of sex steroid receptors was also a predicting factor for good response to progesterone (= decrease in proliferation), while the amount of stroma could not predict that effect.
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Predictors of disease onset and progression in early rheumatoid arthritis : A clinical, laboratory and radiological studyBerglin, Ewa January 2006 (has links)
To diagnose rheumatoid arthritis (RA) during the early stages of the disease is often difficult. The disease course shows great inter-individual variation from mild, self-limiting to very severe destruc-tive disease with extra-articular manifestations. Early aggressive treatment with potentially toxic drugs has been shown to improve the long-term outcome. Thus, it is desirable to make an early reliable di-agnosis and to identify those patients who would benefit from being treated most aggressively. The aim of this thesis was to evaluate laboratory and clinically markers of inflammation as predic-tors of disease course, to compare dual-energy X-ray absorptiometry (DXA) and conventional radiog-raphy (CR) as measures of joint destruction and to investigate the significance of antibodies against cyclic citrullinated peptide (anti-CCP antibodies), rheumatoid factors (RFs) and HLA shared epitope (SE) alleles for the relative risk of future development of RA and as predictors of disease severity in patients with early RA. Patients with RA of recent onset are included in the early RA programme at the Department of Rheumatology, University Hospital, Umeå and are followed longitudinally. The prediction of markers of inflammation for bone loss and radiological outcome was analyzed in the first 43 patients recruited. Radiographs of hands and feet (Larsen score) and bone mineral density (BMD) in hands (DXA), were assessed at baseline, after 1 and 2 years. The disease activity was evaluated clinically and by labora-tory tests. Radiological damage increased significantly during the study and was particularly corre-lated with Larsen score at baseline. BMD in hands decreased significantly in postmenopausal women and the decrease was greater than in healthy matched controls. Radiological progression and bone loss in hands was retarded by an early response to therapy. In a case-control study within the Medical Biobank and the Maternity cohort of Northern Sweden, patients from the early RA programme were identified among blood donors from whom samples had been collected years before onset of symptoms. The prevalence of anti-CCP antibodies and RFs (IgA-RF, IgG-RF and IgM-RF) was investigated in samples from 83 individuals (pre-patients) and com-pared with matched controls. SE alleles were assessed in a sub-group of 59 individuals. Anti-CCP antibodies and RFs preceded onset of RA by several years and increased in prevalence closer to dis-ease onset. Anti-CCP antibodies and IgA-RF significantly predicted the onset of RA. The combination of anti-CCP antibodies and SE alleles was associated with a high relative risk for future development of RA. In a later co-analysis between the register of patients in the early RA programme (n=138) and the Medical Biobank and the Maternity cohort, 93 pre-patient samples were identified. The significance of SE alleles and of the presence of anti-CCP antibodies and RFs before and at disease onset for disease activity and severity was studied. Radiographs of hands and feet were assessed at baseline and after 2 years (Larsen score). The presence of anti-CCP antibodies in pre-patient samples and at baseline was associated with radiological damage, as was presence of all RFs at baseline. A higher titre of anti-CCP antibodies was associated with greater radiological progression. The titre was lowered by a therapeutic response. In multiple logistic regression analyses anti-CCP antibodies, IgA-RF, ESR and swollen joint count predicted greater radiological progression, whilst a therapeutic response predicted a lesser pro-gression. In conclusion, anti-CCP antibodies and IgA-RF are predictors for future onset of RA and for radio-logical destruction and progression. The combination of anti-CCP antibodies and SE alleles is associ-ated with a high relative risk for future RA. Therapeutic response decreases the radiological progres-sion and the bone loss in hands and lowers the titre of anti-CCP antibodies. Conventional radiography is a better measure of joint destruction than DXA.
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Right heart function in health and disease : a doppler echocardiography and doppler tissue imaging study / Högersidig hjärtfunktion hos hjärtfriska och vid hjärtpåverkan : en studie i Doppler ekokardiografi och vävnadsDopplerLindqvist, Per January 2005 (has links)
Background: It is well known that performance of the right ventricle (RV) determines exercise capacity and may confer prognostic information in different cardiopulmonary diseases. To allow optimal patient management, ideal methods to assess right heart function are therefore important. Echocardiography is an attractive investigation for that purpose, although limited by the anatomical and functional complexities of the RV. The aim of the present thesis was to present applicable methods useful in clinical practice by traditional 2D/Doppler echocardiography and Doppler tissue imaging (DTI) in the assessment of global and regional RV function in both health and disease. Methods: The studies were performed on 4 different groups; (1) 255 healthy subjects (125 females), (2) 92 consecutive patients with different cardiac diseases (36 females), (3) 26 patients with systemic sclerosis, (SSc) (21 females) and (4) 26 consecutive patients with heart failure (8 females) undergoing cardiac catheterisation. Results: RV outflow tract fractional shortening (RVOT fs), which is a new method in the assessment of RV function, correlated significantly with RV systolic long axis motion (r= 0.66, p< 0.001), pulmonary artery acceleration time (r= 0.80, p< 0.001) and RV-right atrial peak systolic pressure drop gradient (r= -0.53, p< 0.001). Furthermore, RVOT fs was reduced in patients with pulmonary hypertension whereas RV systolic long axis motion was not in difference. This finding was confirmed after comparing RV function with invasive pressures. In healthy subjects, while the systolic myocardial velocities were preserved over age, the peak isovolumic contraction velocity (IVCv) was weakly increased with advanced age (r= 0.34, p< 0.01). Furthermore, both global and regional E/A ratios were reduced (r= -0.57, r= -0.67, p< 0.001 for both) with age whereas no alteration was found in the myocardial isovolumic relaxation time (IVRt). In patients with systemic sclerosis (SSc) both global (64± 23 vs. 39± 12 ms, p< 0.001) as well as regional (83± 40 vs. 46± 24 ms, p< 0.001) IVRt were prolonged. After evaluating echocardiographic parameters with invasive pressures we found a significant correlation between DTI derived IVRt and pulmonary artery systolic pressures (r= 0.83, p< 0.01) while the IVCv was related to the state of contractility (r= 0.77, p< 0.001). Furthermore, an IVCv below 6 cm/s was shown to be an accurate marker of increased right atrial pressure (>6 mm Hg). In conclusion, RVOT fs can be used as a complementary measurement of RV systolic function, being more sensitive to elevated pulmonary artery systolic pressures than the systolic longitudinal RV motion. Right heart function, mainly the diastolic function, is relatively weakly influenced by age compared to the left heart function. In patients with SSc, we found diastolic disturbances, including a prolonged IVRt and proposed the findings to be early markers related to intermittent pulmonary hypertension. This observation was strengthened after evaluating IVRt against invasive pulmonary artery systolic pressures. IVCv can be used to determine the state of RV contractility and also be used to identify patients with elevated filling pressures. The presented methods can be used to detect early signs of RV dysfunction which might prohibit right heart failure. All presented methods are non-invasive, reproducible, easy obtainable, and thus useful in clinical practice.
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Cobalamin communication in Sweden 1990 – 2000 : views, knowledge and practice among Swedish physiciansNilsson, Mats January 2005 (has links)
Cobalamin (vitamin B12) is one of several essential micronutrients needed by the human organism. Other important micronutritients, which interplay with vitamin B12, are folate and iron. During the last ten years, the attention has been drawn to different forms of neurological disorders supposed to be caused by vitamin B12 deficiency. Vitamin B12 deficiency states are common among elderly patients in primary health care and sometimes in hospital care, especially in geriatric practice. This is a study to define the cobalamin treatment traditions, among Swedish physicians in the period 1990 – 2000. The period was distinguished by an intense debate on the issue by the physicians, an increase of cobalamin consumption, and a shift from parenteral therapy towards oral high-dose therapy. It had been known that symptoms of cobalamin deficiency could start in the nervous system. This knowledge was reinforced by the application of homocysteine and methyl-malonic acid (MMA) in deficiency diagnosis. Introduction of homocysteine and MMA in deficiency diagnosis changed the view on deficiency prevalence, by identifying persons at risk to develop B12 deficiency prior to established symptoms. In this study, Swedish physicians are regarded mainly as receivers of communication about the markers homocysteine and MMA, and deficiency states of cobalamin and folate. The main senders were scientists from North America, Norway, Denmark, and Sweden. This study sets the senders and the receivers of cobalamin communication on a collegial level and quantifies and evaluates the feed-back from the receivers. The receivers, gen¬eral practitioners and geriatricians, appeared to be familiar with old knowledge and frontier concepts in the field. Thus, it is suggested that the increase of B12 prescriptions in Sweden 1990 – 2000 reflected an increased awareness of B12-associated clinical problems among the physicians managing the majority of deficiency patients, although a possible overconsumption of pharmaceutical drugs must be kept in mind.
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Musculoskeletal disorders and whole-body vibration exposure among professional drivers of all-terrain vehiclesRehn, Börje January 2004 (has links)
Musculoskeletal disorders are common among professional driver groups. Ergonomic risk factors at work are often suggested as causative, aggravating or preserving. The general aim with this thesis is to investigate the association between musculoskeletal disorders and physical exposure with special with special focus on whole-body vibration (WBV), among professional drivers of all-terrain vehicles (ATVs). Drivers of ATVs are expsosed to high magnitudes of WBV and shock. This thesis included drivers of forest machines, snowgroomers and snowmobiles. A cross-sectional study revealed that ATV drivers had an increased risk of musculoskeletal symptoms in the neck-shoulder and thoracic regions, even after adjusting for age, smoking habits and psychosocial stress. Prevalence rates were in the range of 1.5-2.9 (CI:1.2-5.2) compared to an age-matched group from the general population. No group of ATV drivers had a significantly increased risk of low back pain. Trend analysis showed no association between symptoms and exposure time. A clinical investigation of a subgroup found that it was for ATV drivers with neck pain to have assymetrical and focal neuropathies, pure or in mix with a nociceptive disorder, in the neck and upper extremities (47-79%), which was in contrast to referents with neck pain who had more nociceptive disorders (27% prevalence of neuropathy). Two studies measured characteristics of seated WBV exposure in forest machines (forwarders), snowgroomers and snowmobiles. The magnitudes of WBV in ATVs, measured and analyzed according to ISO 2631-1, were between 0.5-3.5 m/s2 (frequency weighted vector sum), which was considered high compared to limits suggested by the international standard ISO 2631-1 and the physical agent directive from the Euoropean Union (0.5 m/s2, rms). Drivers of ATVs were exposed to horizontally directed WBV and shocks. Non-neutral neck postures are ergonomic risk factors that occured infrequently and with short duration. The magnitude of seated WBV in forwarder vehicles varied substantiálly depending on model, terrain condition and driver. This may result in different conclusions regarding health risk assessments. The main conclusion from this thesis is that musculoskeletal symptoms and disorders in the neck and upper extremities, among drivers of ATVs, may be a result of long-time exposure to shock-type and horisozontally oriented seated WBV.
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Bone mass and physical activityNordström, Anna January 2004 (has links)
Abstract Weak and osteoporotic bones in old age are an increasing cause of mortality and painful physical impairment of the elderly, especially in the western world. Bone mineral accrual during childhood and adolescence is thought to play a vital role in preventing osteoporosis. Identifying and optimizing the factors influencing peak bone mass is thus important for the prevention of osteoporosis and related fractures. A main aim of this thesis was to investigate the potential effects of various types of weight-bearing physical activity on bone accretion in young males just out of puberty. The results from our subgroups of athletes consisting of badminton, ice hockey, and soccer players suggest that weight-bearing physical activity gives rise to regional specific bone response that is determined by the degree of impact of the activity in areas subject to mechanical loading (papers I–IV). In summary, the bone is sensitive to loading after puberty in males, and important bone mass gains can be achieved by proper amount and type of exercise. Another aim of this thesis was to studythe effect of detraining on weight-bearing and non-weight-bearing bone in a cohort of adolescent males who participated in ice hockey and soccer training. Our results indicate that exercise-induced bone mineral density benefits decline, predominantly in weight-bearing bones, after retirement from an active sports career (papers II–IV). High bone density stemming from physical loading might be at least partly preserved even by reduced physical activity at nonweight-bearing sites after about three years of reduced activity (III, IV). A final aim was to follow prospectively the development of BMD during years of reduced activity in former male athletes, and evaluate whether exercise during adolescence could be associated with fewer fractures in old age. We found fewer fragility fractures in a cohort of 400 former athletes compared to in 800 age-matched controls. Thus, high bone density stemming from previous weight-bearing physical activity may reduce the risk of sustaining fragility fractures in the elderly. Key words: physical activity, peak bone mineral density, males.
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Chronic obstructive pulmonary disease (COPD) : prevalence, incidence, decline in lung function and risk factorsLindberg, Anne January 2004 (has links)
The Obstructive Lung Disease in Northern Sweden (OLIN) Studies started in 1985 as an epidemiological project with the aim to detect preventable risk factors for obstructive lung diseases and allergy. In recent years there has been a focus also on obstructive sleep apnoea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD) besides asthma and allergy. The aim of this thesis was to estimate the prevalence and incidence of COPD, risk factors for COPD, and decline in lung function in relation to COPD. The OLIN cohort I (cI) was recruited in 1985/86 and consisted of all 6610 subjects born 1919-20, 1934-35 and 1949-50 in eight geographical areas of Norrbotten. A postal questionnaire survey was performed in 1985/86, 1992 and in 1996. All subjects reporting respiratory symptoms at the questionnaire in 1985/86 were invited to examination in 1986, 1996 and 2002-03. A random sample of 1500 subjects from the participants at the 1996 postal questionnaire survey was invited to examination in 1996 and 2003. The participation rate has been high, ≥85%. The OLIN cohort III (cIII) was recruited in 1992, a postal questionnaire was sent to a random sample of 5681 subjects aged 20-69 years. In 1994/95 a random sample of 970 subjects were invited to examination of whom 666 participated. The prevalence of COPD in the general population sample (cIII) in ages <45 was 4.1%, 11.6%, 9.1%, and 5.1% according to the criteria of BTS1 , ERS2 , GOLD3 , and ATS4 respectively. The corresponding figures in ages ≥45 were 9.7%, 15.4%, 17.1%, and 16.5% respectively. In the age-stratified general population sample (>45 y, cI), the prevalence was 8.1% and 14.3% according to the BTS and GOLD criteria. The prevalence was strongly associated with higher age and smoking but not gender. The prevalence among smokers 76-77 years old was 45% and 50% (BTS and GOLD criteria). A majority of subjects with COPD had respiratory symptoms (in prevalent BTS 94%), most commonly cough and sputum production. Nearly a half of the subjects with COPD had contacted health care due to respiratory complaints other than common colds, but only a minority reported a physician diagnosis relevant for COPD (16% of prevalent COPD according to BTS in cIII, 31% in cI). The 10-year cumulative incidence of COPD (1986-1996) was estimated at 8.2% (BTS) and 13.5% (GOLD) in the symptomatics of cI, associated with higher age and smoking but not gender. Persistent smoking, male gender and reported chronic productive cough were associated with a faster decline in FEV1. Among incident cases of COPD a large proportion (23% of incident BTS) had a rapid decline in FEV1, >90 ml/year, corresponding to a decrease of 28 percent-units of normal value during ten years.The 7-year cumulative incidence of COPD in the random sample of cI (1996-2003) was estimated at 4.9% and 11.0% (NICE guidelines5 and GOLD) and associated with smoking but not gender. The incidence according to GOLD, but not NICE, was associated with increasing age. In multi-variate analysis most respiratory symptoms were markers of increased risk for developing COPD. In conclusion, the prevalence and the incidence of COPD were associated with age and smoking and affected by the use of different spirometric criteria. Respiratory symptoms marked an increased risk for developing COPD. A high proportion of subjects developing COPD had a rapid decline in lung function. Further, there was a substantial underdiagnosis of COPD. 1 British Thoracic Society: FEV1/VC<0.70 & FEV1<80%predicted (pred), 2 European Respiratory Society: FEV1/VC<88%pred in men, <89%pred in women, 3 Global initiative for Chronic Obstructive Lung Disease:FEV1/FVC<0.70, 4 American Thoracic Society: FEV1/FVC<0.75 + symptoms or physician diagnosis, 5 The British National Institute for Clinical Excellence: FEV1/FVC<0.70 & FEV1<80%pred.
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Treatment of Experimental Neuroblastoma with Angiogenic InhibitorsBäckman, Ulrika January 2003 (has links)
Neuroblastoma is a childhood cancer that originates from neuroblasts in the peripheral nervous system. Neuroblastoma show considerable heterogeneity with respect to location, responsiveness to treatment and prognosis. Since current therapy involves drugs with risk of serious side effects in the growing child, there is a clinical need for more effective and less toxic treatment strategies. Angiogenesis, the formation of new blood vessels, is critical for tumor progression. Specific inhibition of tumor-induced angiogenesis should restrict growth of most solid tumors and thereby provide a new treatment strategy. The aim of this study was to investigate the effects of angiogenic inhibition in experimental neuroblastoma in mice. We found that experimental neuroblastomas expressed the perhaps most potent angiogenic growth factor, VEGF-A, and that plasma VEGF-A levels correlated with tumor size. SU5416, a novel antagonist of VEGFR-1 and 2, reduced angiogenesis and tumor growth in our model. We also investigated the properties of SU11657, a new, orally available, synthetic small molecule multi-targeted tyrosine kinase inhibitor. SU11657, at a well-tolerated dose, was more potent than SU5416 in reducing tumor growth rate and angiogenesis, even in MYCN-amplified tumors. Chemotherapeutics can also inhibit angiogenesis, when administrated daily in a non-toxic dose. CHS 828, a new chemotherapeutic, given orally, alone induced complete neuroblastoma regression in 44 % of the animals. Furthermore, the bisphosphonate zoledronic acid, developed to reduce bone resorption, showed anti-tumor activity in our model. Zoledronic acid was more potent than the angiogenic inhibitor TNP-470. Thus bisphosphonates may have other beneficial properties in patients with cancer apart from preventing bone resorption. In conclusion, SU5416, SU11657, CHS 828, and zoledronic acid represent new drugs with potent anti-tumor effects. Angiogenic inhibition as single therapy or in combination with chemotherapeutics may be beneficial in the treatment of rapidly growing and highly vascularized solid tumors of childhood such as neuroblastoma.
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