Treatment with zoledronic acid ameliorates negative geometric changes in the proximal femur following acute spinal cord injury

Acute spinal cord injury is associated with rapid bone loss and an increased risk of fracture. In this double-blind, randomized, placebo-controlled trial, 17 patients were followed for 1 year after administration of either 4 or 5 mg of zoledronic acid or placebo. Bone mineral density (BMD) and structural analyses of the proximal femur were performed using the hip structural analysis program at entry, 6 months, and 12 months. The 17 subjects completed 12 months of observation, nine receiving placebo and eight zoledronic acid. The placebo group showed a decrease in BMD, cross-sectional area, and section modulus and an increase in buckling ratio at each proximal femur site at 6 and 12 months. Six months after zoledronic acid, BMD, cross-sectional area, and section modulus increased at the femoral neck and intertrochanteric regions and buckling ratio decreased consistent with improved bone stability. However, at 12 months, the femoral narrow-neck values declined to baseline. In contrast to placebo, the intertrochanteric region and femur shaft were maintained at or near baseline through 12 months in the zoledronic acid-treated group. Urine N-telopeptide excretion was increased at baseline and declined in both the placebo and treatment groups during the 12 months of observation. We conclude that a single administration of zoledronic acid will ameliorate bone loss and maintain parameters of bone strength at the three proximal femur sites for 6 months and at the femur intertrochanteric and shaft sites for 12 months.

Development of conventional and real-time nucleic acid sequence-based amplification assays for detection of Chlamydophila pneumoniae in respiratory specimens

Isothermal nucleic acid sequence-based amplification (NASBA) was applied to the detection of Chlamydophila pneumoniae 16S rRNA by using the NucliSens basic kit (bioMérieux, Boxtel, The Netherlands). The assay was originally developed as a conventional NASBA assay with electrochemiluminescence detection and was subsequently adapted to a real-time NASBA format by using a molecular beacon. C. pneumoniae RNA prepared from a plasmid construct was used to assess the analytical sensitivity of the assay. The sensitivity of the NASBA assay was 10 molecules of in vitro wild-type C. pneumoniae RNA and 0.1 inclusion-forming unit (IFU) of C. pneumoniae. In spiked respiratory specimens, the sensitivity of the C. pneumoniae NASBA assay varied between 0.1 and 1 IFU/100 mul sample, depending on the type of specimen. Finally, conventional and real-time NASBA were applied to respiratory specimens previously tested by PCR. A 100% concordance between the test results was obtained.

Randomized Phase III Trial Comparing Irinotecan/Cisplatin With Etoposide/Cisplatin in Patients With Previously Untreated Extensive-Stage Disease Small-Cell Lung Cancer

Purpose

Etoposide and cisplatin (EP) has been a standard treatment for extensive-disease small-cell lung cancer (SCLC). An earlier phase III trial reported improved survival for patients receiving irinotecan plus cisplatin (IP) versus EP. Our trial was designed to determine if a modified weekly regimen of IP would provide superior survival with less toxicity than EP.

Patients and Methods

The primary objective was to compare overall survival in extensive-disease SCLC patients randomly assigned to receive IP (n = 221) or EP (n = 110). Patients were randomly assigned in 2:1 ratio to cisplatin 30 mg/m2 intravenously (IV) + irinotecan 65 mg/m2 IV on days 1 and 8 every 21 days, or cisplatin 60 mg/m2 IV on day 1, and etoposide 120 mg/m2 IV on days 1 to 3 every 21 days for at least four cycles, until progressive disease, or until intolerable toxicity resulted.

Results

Selected grade 3/4 toxicities for IP/EP were: neutropenia (36.2% v 86.5%; P < .01), febrile neutropenia (3.7% v 10.4%; P = .06), anemia (4.8% v 11.5%; P = .02), thrombocytopenia (4.3% v 19.2%; P < .01), vomiting (12.5% v 3.8%; P = .04), and diarrhea (21.3% v 0%; P < .01). There was no significant difference in response rates (48% v 43.6%), median time to progression (4.1 v 4.6 months), or overall survival (median survival time, 9.3 months v 10.2 months; P = .74).

Conclusion

Treatment with this dose and schedule of IP did not result in improved survival when compared with EP. Fewer patients receiving IP had grade 3/4 anemia, thrombocytopenia, neutropenia, and febrile neutropenia compared with patients receiving EP, but more had grade 3/4 diarrhea and vomiting.

Two quality control exercises involving nucleic acid amplification methods for detection of Mycoplasma pneumoniae and Chlamydophila pneumoniae and carried out 2 years apart (in 2002 and 2004)

The quality performance of laboratories for the detection of Mycoplasma pneumoniae and Chlamydophila pneumoniae by two quality control (QC) exercises with a 2-year interval was investigated. For the 2002 QC exercise, specimens were spiked with M. pneumoniae at concentrations of 5,000, 500, 50, and 0 color-changing units (CCU)/100 microl. The limit of detectability was 50 CCU/100 microl. Therefore, this concentration was omitted from the 2004 panel and was excluded from the analysis. In 2002, 2 out of 12 participants obtained 100% correct results, 2 out of 12 produced false-positive results, and 10 out of 12 had between 0 out of 9 and 8 out of 9 correct positive results. In 2004, correct results were obtained in 15 out of 18 tests, and no false-positive results were reported. In 2002, specimens were spiked with C. pneumoniae at concentrations of 490, 49, 4.9, and 0 inclusion-forming units/100 microl (IFU/100 microl). In the 2004 panel, samples spiked with a lower dilution of 0.49 IFU/100 microl were added to the panel. For the C. pneumoniae QC, correct results were produced in 12 out of 16 and 13 out of 18 tests in 2002 and in 2004, respectively. Both multiplex PCR and nucleic acid sequence-based amplification (NASBA) formats scored a smaller number of samples positive than the monoplex reactions.

Non-invasive coronary angiography with 16-slice spiral computed tomography: image quality in patients with high heart rates

The purpose of this study was to assess segment image quality at high heart rates using 16-slice computed tomography and differential reconstruction for major coronary vessels. According to the following protocol, 16-slice CT coronary angiography in 46 patients with a mean heart rate of 86.3+/-11.8 was reconstructed. At three transverse planes, preview series were obtained and motion artifacts evaluated in 5% increments from 0-95% within the cardiac cycle. Relying on image quality in the previews, reconstructions were performed at three z-positions for each patient. Segment image quality was assessed in terms of artifacts and visibility. The effects of heart rate and trigger delay on image quality were analyzed. Optimal image quality was achieved at 25 to 35% of the cardiac cycle for the left circumflex (CX) and right coronary artery (RCA) or 30 to 40% for the left main (LM) and left anterior descending artery (LAD). Sixteen-slice CT and differential reconstruction produced good image quality with a low percentage of motion-degraded proximal and middle segments (8.8%). Grades were 1.5 for the LM, 1.9 for the LAD, 2.0 for the CX and 2.3 for the RCA. At high heart rates, good image quality of the coronary arteries is achieved by 16-slice CT and a sophisticated reconstruction strategy at peak to late systole.

[Axial load in case of press-fit fixation of the ACL graft--a fundamental study]

AIM

The aim of this study was the determination of the axial fixation load resting on smooth press-fit dowels needed for fixation of the patellar tendon graft (BTB) in order to reach the same fixation properties compared to the interference screw on anterior cruciate ligament (ACL) plasty.

METHOD

Bovine test specimens with 27 BTB grafts fixed in tibial drill holes were used and divided in 3 groups: interference screw, and press-fit cylinder (Ø 7 mm) with 150 N and 100 N axial loads. Prior to fixation, impactation of the transplant into bone was carried out. Failure testing was done in a tensiometer at a cross-head speed of 50 mm/min. Determinations of peak load and stiffness were also made.

RESULTS

Similar peak loads and stiffness were reached on introducing a press-fit dowel (slashed circle 7 mm) with 100 N and 150 N axial load compared to interference screw fixation of the BTB graft. Peak load: 988.1 N +/- 365.1 (screw) versus 1 210.4 N +/- 292.4 (dowel 150 N) and 1 109.8 N +/- 505.4 (dowel 100 N). Stiffness: 86.4 N/mm +/- 20.5 (screw) versus 102.4 N/mm +/- 15.2 (dowel 150 N) and 77.1 N/mm +/- 11.0 (dowel 100 N). There was no significant difference.

CONCLUSION

When introducing a press-fit dowel (slashed circle 7 mm) with 100 N axial load into a preformed bone bed, the same fixation properties are reached as in the case of an interference screw on BTB-ACL plasty.

Image quality and diagnostic accuracy of 16-slice multidetector computed tomography for the detection of coronary artery disease in obese patients

BACKGROUND

Cardiac multislice spiral computed tomography (MSCT) scanners permit visualization of the coronary arteries with an overall good sensitivity (sens) and specificity (spec). However, in obese patients (pts), who are at higher risk to develop coronary artery disease (CAD), image quality of MSCT is supposed to be limited. At present, there are no data whether the accuracy of MSCT depends on the body mass index (BMI). Thus, we compared the catheter-controlled MSCT results from normal weight and obese pts in a cohort of 117 pts with regard to sens, spec, positive predictive value (PPV), negative predictive value (NPV) and image quality.

METHODS AND MATERIAL

In all, 21 normal weight pts (group I: BMI<25, 64.6+/-11.1 years, number of risk factors 2.1+/-1.1), 60 pts with mild overweight (group II: BMI 25-30, 64.6+/-8.9 years, number of risk factors 3.4+/-1.0) and 36 obese pts (group III: BMI >30, 63.0+/-8.5 years, number of risk factors 3.4+/-0.9) were examined by MSCT (Sensation 16 Speed 4 D((R)), Siemens, Germany, gantry rotation time 375 ms) and invasive coronary angiography. MSCT results were compared blinded to the results of the coronary angiography with regard to the presence or absence of a significant stenosis (>50%) in a modified AHA 13 segment (sgt) model. Image quality was assessed on a qualitative scale between 1 (very good) and 5 (insufficient image quality) for each sgt.

RESULTS

Sens, spec, PPV and NPV were statistically not different in all three groups (I: 0.88/0.97/0.91/0.96, II: 0.83/0.97/0.88/0.95, III: 0.87/0.99/0.96/0.96). 3 pts (group I 1, group II 2) had to be excluded from analysis due to technical problems. Group I had significantly less risk factors (P < 0.001) and image quality was significantly better than in group II and III (P < 0.05). Group II and III did not differ with regard to risk factors or image quality.

CONCLUSIONS

Overweight and obesity have an impact on MSCT image quality but did not hamper the diagnostic accuracy. Thus, MSCT is a noninvasive method to detect or rule out CAD also in pts with higher BMI. These retrospective data have to be confirmed in larger prospective trials.

Image quality and diagnostic accuracy of non-invasive coronary imaging with 16 detector slice spiral computed tomography with 188 ms temporal resolution

OBJECTIVE

To evaluate image quality and clinical accuracy in detecting coronary artery lesions with a new multidetector spiral computed tomography (MDCT) generation with 16 detector slices and a temporal resolution of 188 ms.

METHODS

124 consecutive patients scheduled for invasive coronary angiography (ICA) were additionally studied by MDCT (Sensation 16 Speed 4D). MDCTs were analysed with regard to image quality and presence of coronary artery lesions. The results were compared with ICA.

RESULTS

120 of 124 scans were successful. The image quality of all remaining 120 scans was sufficient (mean (SD) heart rate 64.2 (9.8) beats/min, range 43-95). The mean calcium mass was 167 (223) mg (range 0-1038). Thirteen coronary segments were evaluated for each patient (1560 segments in total). Image quality was graded as follows: excellent, 422 (27.1%) segments; good, 540 (34.6%) segments; moderate, 277 (17.7%) segments; heavily calcified, 215 (13.8%) segments; and blurred, 106 (6.8%) segments. ICA detected 359 lesions with a diameter stenosis > 50% and MDCT detected 304 of 359 (85%). Sensitivity, specificity, and positive and negative predictive values were 85%, 98%, 91%, and 96%, respectively. The correct clinical diagnosis (presence or absence of at least one stenosis > 50%) was obtained for 110 of 120 (92%) patients.

CONCLUSIONS

MDCT image quality can be further improved with 16 slices and faster gantry rotation time. These results in an unselected population underline the potential of MDCT to become a non-invasive diagnostic alternative, especially for the exclusion of coronary artery disease, in the near future.

"Bounce at the Bell": a novel program of short bouts of exercise improves proximal femur bone mass in early pubertal children

OBJECTIVES

To examine the effects of a simple and inexpensive physical activity intervention on change in bone mass and structure in school aged children.

METHODS

Fifty one children (n = 23 boys and 28 girls; mean age 10.1 years) participated in "Bounce at the Bell" which consisted of 10 counter-movement jumps 3x per day (total approximately 3 min/day). Controls were 71 matched children who followed usual school practice. We assessed dietary calcium, physical activity, physical performance, and anthropometry in September and after 8 months of intervention (June). We measured bone mineral content (BMC) and bone area at the lumbar spine, total body, and proximal femur. Proximal femur scans were also analysed for bone geometry and structural strength using the hip structural analysis program. Lean and fat mass (g) were also calculated.

RESULTS

Groups were similar at baseline and did not differ in weight, height, total body, lumbar spine, proximal femur, or femoral neck BMC. Control children had a greater increase in adjusted total body BMC (1.4%). Intervention children gained significantly more BMC at the total proximal femur (2%) and the intertrochanteric region (27%). Change in bone structural parameters did not differ between groups.

CONCLUSIONS

This novel, easily implemented exercise program, took only a few minutes each day and enhanced bone mass at the weight bearing proximal femur in early pubertal children. A large, randomised study of boys and girls should be undertaken powered to test the effectiveness of Bounce at the Bell in children at different stages of maturity, and in boys and girls independently.

Biochemical and immunological properties of cytokines conjugated to dendritic polymers

Here we describe a post-translational modification of SC-63032, a variant of the species restricted, multi-lineage hematopoeitic factor human interleukin-3 (hIL-3). We have made two new dendritic polymer (polyamidoamine or PAMAM dendrimers, generation 5)-SC-63032 bioconjugates. Using two distinct chemistries (one of which is novel to this work), we achieved site-specific conjugation with respect to the amino acid in the proteins ligated to the dendrimers. In both bioconjugates, conjugated cytokine maintains its ability to bind the hIL-3 alpha receptor subunit, but is significantly (about 10-fold) less potent in inducing hIL-3 dependent in vitro cell proliferation than is the free cytokine. In vivo data indicates that conjugation decreases the immunogenicity of the conjugated cytokine modestly. In the absence of pharmacokinetic or biodistribution effects associated with the bioconjugates that increase their potency in vivo (which can only be tested in a higher primate, due to the species restriction of hIL-3 and its derivatives), these immune mitigation effects may be too small to be therapeutically significant. Though unmodified PAMAM dendrimers fail to elicit an antibody response in mice, protein conjugation to dendrimers haptenizes them, and a dendrimer-specific antibody response is produced. In toto, the principal limitation of the dendrimer-cytokine bioconjugates herein is in their reduced receptor affinity and potency in vitro. Were the in vivo potency of the bioconjugates to parallel the in vitro potency of the conjugates reported here, it is likely that particular dendrimer bioconjugates could not justify their higher costs of goods relative to the parent SC-63032 molecule, though retention of SC-63032 biological activities in conjugates suggests that other cytokine-dendrimer bioconjugates may be bioactive. This is good news to the nanotechnology community, in as much as PAMAM dendrimers are among the monodisperse polymeric nanomaterials available, and these results show that they can be used successfully in conjugates to bioactive proteins.

Clinical use of multislice spiral computed tomography in 210 highly preselected patients: experience with 4 and 16 slice technology

OBJECTIVE

To report an initial experience with multislice spiral computed tomography (MSCT) coronary imaging, as well as differences in diagnostic accuracy between 4 slice and 16 slice MSCT technology.

METHODS AND RESULTS

210 patients underwent MSCT coronary angiography (4 slices, n = 120; 16 slices, n = 90; suspicion of coronary artery disease, n = 158; suspicion of restenosis, n = 52). Recommendations for further diagnostic tests were based on the MSCT results. Patients were interviewed by telephone after a mean (SD) of 449 (169) days to evaluate their further clinical course. MSCT detected significant lesions in 90 of 210 (43%) patients and invasive coronary angiography (ICA) was recommended. MSCT excluded significant lesions in 120 of 210 (57%) patients. ICA was actually performed in 44 of 210 (21%) patients (corresponding results, 27 of 44 (61%); false positive, 11 of 44 (25%); false negative, 6 of 44 (14%)). No significant differences were found between 4 and 16 slice imaging. No major cardiac event occurred during follow up.

CONCLUSIONS

MSCT was found to be useful to evaluate the need for invasive diagnostic procedures. However, the false negative results underline that further improvements of image quality are required before MSCT can replace ICA in carefully selected patients.

Non-invasive evaluation of atherosclerosis with contrast enhanced 16 slice spiral computed tomography: results of ex vivo investigations

OBJECTIVE

To evaluate the diagnostic accuracy of 16 slice computed tomography (CT) in determining plaque morphology and composition in an experimental setting. The results were compared with histopathological analysis as the reference standard.

METHODS

Nine human popliteal arteries derived from amputations because of atherosclerotic disease were investigated with multislice spiral CT (MSCT). Atherosclerotic lesions were morphologically classified (completely or partially occlusive, concentric, eccentric), and tissue densities were determined within these plaques. In addition, vessel dimensions were quantitatively measured.

RESULTS

The results were compared with histological analysis. The concordance index kappa for morphological classification was 0.88. Plaque density (n = 51 lesions) was significantly different (p < 0.0001) between lipid rich, fibrotic, and calcified lesions (Stary stage III: n = 2, 58 (8) Hounsfield units (HU); Stary V: n = 11, 50 (21) HU; Stary VI: n = 14, 96 (42) HU; Stary VII: n = 6, 858 (263) HU; Stary VIII: n = 18, 126 (99) HU). The concordance index kappa for the classification of plaques based on density was 0.51. Vessel dimensions had a good correlation (r = 0.98).

CONCLUSIONS

16 slice CT was found to be a reliable non-invasive imaging technique for assessing atherosclerotic plaque morphology and composition. Although calcified lesions can be differentiated from non-calcified lesions, the diagnostic accuracy in further subclassifying non-calcified plaques as lipid rich and fibrotic is low, even under experimental conditions.

Relationship between Alzheimer’s disease clinical stage and Gq/11 in subcellular fractions of frontal cortex

Alzheimer's disease (AD) is associated with impaired coupling of cell surface muscarinic cholinergic receptors to G proteins of the Gq/11 class in brain. This alteration may contribute to progression of cognitive impairment during the course of the disease. We hypothesized that increasing severity of cognitive impairment would be related to decreased levels of Gq/11 detected in key subcellular fractions made from postmortem brain tissue. In this study, we used Western blotting to determine the quantity of Gq/11alpha in P2, synaptic plasma membrane, cytoplasm, microsomal membrane, and lipid raft fractions prepared from superior frontal cortex gray matter of 25 patients with clinical AD confirmed by post-mortem examination. Multiple linear regression analysis that adjusted for age, sex, and education showed a linear relationship between frontal cortex synaptic plasma membrane Gq/11alpha levels and severity of cognitive impairment determined by Mini Mental State score measured proximate to death.