The prevalence of redundant nerve roots in standing positional MRI decreases by half in supine and almost to zero in flexed seated position: a retrospective cross-sectional cohort study

PURPOSE

This retrospective cross-sectional cohort study investigated the influence of posture on lordosis (LL), length of the spinal canal (LSC), anteroposterior diameter (APD L1-L5), dural cross-sectional area (DCSA) of the lumbar spinal canal, and the prevalence of redundant nerve roots (RNR) using positional magnetic resonance imaging (MRI) (0.6 T).

METHODS

Sixty-eight patients with single-level degenerative central lumbar spinal stenosis (cLSS) presenting with RNR in the standing position (STA) were also investigated in supine (SUP) or neutral seated (SIT) and flexed seated (FLEX) positions. Additionally, 45 patients complaining of back pain and without MRI evidence of LSS were evaluated. Statistical significance was set at p < 0.05.

RESULTS

Controls (A) and patients with cLSS (B) were comparable in terms of mean age (p = 0.88) and sex (p = 0.22). The progressive transition from STA to FLEX led to a comparable decrease in LL (p = 0.97), an increase in LSC (p = 0.80), and an increase in APD L1-L5 (p = 0.78). The APD of the stenotic level increased disproportionally between the different postures, up to 67% in FLEX compared to 29% in adjacent non-stenotic levels (p < 0.001). Therefore, the prevalence of RNR decreased to 49, 26, and 4% in SUP, SIT, and FLEX, respectively.

CONCLUSION

The prevalence of RNR in standing position was underestimated by half in supine position. Body postures modified LL, LSC, and APD similarly in patients and controls. Stenotic levels compensated for insufficient intraspinal volume with a disproportionate enlargement when switching from the STA to FLEX.

Massive expansion of human induced pluripotent stem cells resulting in efficient biobanking and functional 3D tissue analysis of genetic cardiomyopathies

Introduction

Over the past decade, various protocols were established to ensure efficient differentiation of hiPSC into cardiomyocytes (CMs). A major limitation, however, remained the batch-to-batch variability of hiPSC-CM efficiency and cell number. Here, we suggest an approach in which concomitant GSK-3β inhibition and removal of cell-cell contact inhibition, resulted in a massive proliferative response of hiPSC-CMs1–3. This efficient method allows expansion and passaging of functional hiPSC-CMs, that routinely can be cryopreserved and subsequently used as a stable cell source for the downstream applications, such 3D in vitro models for the disease modelling of dilated cardiomyopathy (DCM). We focussed on the deletion of arginine 14 in the PLN gene (R14del), which is associated with severe heart failure in DCM patients, associated with arrhythmias, cardiac fibrosis and premature death.

Methods

Subsequent expansion of hiPSC-CM cultures is generally modest (&lt;10 fold). Here, we describe a cost-effective strategy for massive expansion (up to 250-fold) of high-purity hiPSC-CMs relying on two aspects; 1) inhibition of cell-cell contact via low-density seeding and serial passaging in culture flask-format, 2)small molecular glycogen synthase kinase-3β inhibition with CHIR99021 (CHIR). Patient-specific hiPSC-CMs harbouring a PLNR14del mutation were generated and used for EHT formation and functional follow-up.

Results

We observed that proliferating hiPSC-CMs, especially within the first 2 passages, can routinely be cryopreserved and subsequently further expanded or utilized in downstream applications. Moreover, using this strategy, it is possible to produce ultimately &gt;1 billion CMs within 3–5 weeks starting with one differentiation batch of day 11 hiPSC-CMs, without the need for cell sorting or selection. Expanded hiPSC-CMs retain their capacity to mature and allows fibrin-based engineered heart tissues (EHTs) formation. Previously expanded CMs from PLNR14del patient-specific hiPSC were used to generate EHT and displayed a reduced force phenotype (0.137±0.012 mN) vs healthy control (0.229±0.030 mN) and isogenic control (0.224±0.008 mN) in previously expanded CMs.

Conclusion

We provpresent a novel strategy for the massive expansion of functional hiPSC-CMs with concomitant GSK-3β inhibition and low cell density culture that ultimately generates up to a 250-fold increase in hiPSC-CM numbers. Expansion healthy control hiPSC-CMs does not limit the subsequent maturation process, and moreover cells remain fully functional such as required for downstream tissue engineering approaches. Therefore, CM expansion forms a well-controlled platform for upscaling hiPSC-CM production for functional 3-dimensionale PLN cardiac disease models, large drug screenings and multiple translational/regenerative applications.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): PLN Foundation

H3F3A-mutated giant cell tumour of bone without giant cells-clinical presentation, radiology and histology of three cases

AIMS

Giant cell tumour of bone (GCTB) is histologically defined as a lesion containing reactive giant cells and a neoplastic mononuclear cell population; in up to 92% of cases, GCTB is characterised by a specific mutation of the histone gene H3F3A. The cellular composition ranges from giant-cell-rich to giant-cell-poor. The diagnosis of GCTB can be challenging, and several other lesions need to be excluded, e.g. aneurysmal bone cysts, non-ossifying fibromas, chondroblastomas, brown tumours, and giant-cell-rich osteosarcomas. Our aim was to analyse the clinical history, imaging, molecular pathology and histology of three H3F3A-mutated bone tumours without detectable giant cells. None of the patients received denosumab therapy.

METHODS AND RESULTS

Diagnostic material was obtained by curettage or resection and/or biopsy. Common histomorphological features of all three reported lesions were fibrocytic, oval cells in a background of osteoid and an absence of multinuclear giant cells as confirmed with CD68 immunohistochemistry. We used immunohistochemistry and Sanger sequencing to demonstrate positivity for the H3.3 p.G34W mutation. Differential diagnoses were systematically excluded on the basis of histomorphology, immunohistochemistry, and fluorescence in-situ hybridisation. The imaging (radiography, computed tomography, and magnetic resonance imaging) for all three cases is presented and discussed.

CONCLUSIONS

We believe that these GCTBs without giant cells expand one end of the heterogeneous range of GCTB. Because of the lack of giant cells, correct diagnosis of GCTB is challenging or even impossible on histological grounds alone. In these cases, detection of the characteristic H3F3A mutation (G34W-specific antibody RM263 or sequencing) is extremely helpful for diagnosing those lesions without giant cells as giant cell tumours of bone.

Automated age estimation of young individuals based on 3D knee MRI using deep learning

Age estimation is a crucial element of forensic medicine to assess the chronological age of living individuals without or lacking valid legal documentation. Methods used in practice are labor-intensive, subjective, and frequently comprise radiation exposure. Recently, also non-invasive methods using magnetic resonance imaging (MRI) have evaluated and confirmed a correlation between growth plate ossification in long bones and the chronological age of young subjects. However, automated and user-independent approaches are required to perform reliable assessments on large datasets. The aim of this study was to develop a fully automated and computer-based method for age estimation based on 3D knee MRIs using machine learning. The proposed solution is based on three parts: image-preprocessing, bone segmentation, and age estimation. A total of 185 coronal and 404 sagittal MR volumes from Caucasian male subjects in the age range of 13 and 21 years were available. The best result of the fivefold cross-validation was a mean absolute error of 0.67 ± 0.49 years in age regression and an accuracy of 90.9%, a sensitivity of 88.6%, and a specificity of 94.2% in classification (18-year age limit) using a combination of convolutional neural networks and tree-based machine learning algorithms. The potential of deep learning for age estimation is reflected in the results and can be further improved if it is trained on even larger and more diverse datasets.

Hip abductor tendon pathology visualized by 1.5 versus 3. 0 Tesla MRIs

INTRODUCTION

Hip abductor tendinopathies are becoming increasingly recognized as clinically relevant disorders. However, knowledge about prevalence of abductor tendinopathies and associated disorders of adjacent hip articular and periarticular structures is limited. In this context, the relative diagnostic value of 1.5-T vs. 3.0-T MRI magnets has not been studied yet.

MATERIALS AND METHODS

Pelvic MRI scans of 1000 hips from 500 consecutive unselected patients (341 in 3.0-T/159 in 1.5-T magnets, with standardized scanning protocols over the entire study period) were analysed for the detection of abductor tendinosis, calcifying tendinitis, partial or full-thickness tears of the M. gluteus medius (GMed) and/or -minimus (GMin) and trochanteric bursitis (TB). The occurrence of these lesions was correlated to the presence of muscle atrophy (MA) of GMed/GMin, hip joint effusion (JE) and osteoarthritis (OA).

RESULTS

Peritrochanteric lesions were observed with a prevalence of 31.4% of all patients (22.3% of all hips). TB occurred almost exclusively in the presence of GMed/GMin tendinopathies. Compared to overall prevalence, patients with MA displayed lesions of GMed/GMin or TB in 70%, patients, with OA in 30% and with JE in 23%. These lesions occurred significantly more often ipsilateral to MA and OA than contralateral (MA: 76.8% vs. 23.2%, p < 0.001; OA: 64.4% vs. 35.6%, p = 0.03; JE: 62.7% vs. 37.3%, p = 0.08). Significantly more tendon lesions, in particular specific radiological diagnoses like partial/full-thickness tears, were detected by 3.0-T MRI than by 1.5 T (p = 0.019).

CONCLUSIONS

Peritrochanteric lesions are a prevalent pathology that should specifically be looked for, preferably by 3.0-T MRI, independent of concomitant hip joint pathology.

Redundant nerve roots in lumbar spinal stenosis: inter- and intra-rater reliability of an MRI-based classification

Purpose

Patients with central lumbar spinal stenosis (LSS) have a longer symptom history, more severe stenosis, and worse postoperative outcomes, when redundant nerve roots (RNRs) are evident in the preoperative MRI. The objective was to test the inter- and intra-rater reliability of an MRI-based classification for RNR.

Methods

This is a retrospective reliability study. A neuroradiologist, an orthopedic surgeon, a neurosurgeon, and three orthopedic surgeons in-training classified RNR on 126 preoperative MRIs of patients with LSS admitted for microsurgical decompression. On sagittal and axial T2-weighted images, the following four categories were classified: allocation (A) of the key stenotic level, shape (S), extension (E), and direction (D) of the RNR. A second read with cases ordered differently was performed 4 weeks later. Fleiss and Cohen’s kappa procedures were used to determine reliability.

Results

The allocation, shape, extension, and direction (ASED) classification showed moderate to almost perfect inter-rater reliability, with kappa values (95% CI) of 0.86 (0.83, 0.90), 0.62 (0.57, 0.66), 0.56 (0.51, 0.60), and 0.66 (0.63, 0.70) for allocation, shape, extension, and direction, respectively. Intra-rater reliability was almost perfect, with kappa values of 0.90 (0.88, 0.92), 0.86 (0.84, 0.88), and 0.84 (0.81, 0.87) for shape, extension, and direction, respectively. Intra-rater kappa values were similar for junior and senior raters. Kappa values for inter-rater reliability were similar between the first and second reads (p = 0.06) among junior raters and improved among senior raters (p = 0.008).

Conclusions

The MRI-based classification of RNR showed moderate-to-almost perfect inter-rater and almost perfect intra-rater reliability.

Dysfunktionelle respiratorische Symptome bei Kindern und Jugendlichen

Dysfunktionelle respiratorische Symptome sind durch rekurrierend oder chronisch auftretende respiratorische Krankheitszeichen charakterisiert, die sich nicht durch strukturelle Besonderheiten der Atemwege erklären lassen und Symptome somatischer Erkrankungen imitieren können (somatoforme Atemstörungen). Die Systematisierung von dysfunktionellen respiratorischen Symptomen sowie die Entwicklung diagnostischer und therapeutischer Algorithmen sind relativ junge Arbeitsfelder der Pädiatrischen Pneumologie. Inzwischen sind diagnostische Mindestkriterien vorgeschlagen worden, die zur besseren Erkennung und Abgrenzung von somatischen Erkrankungen beitragen sollen. Eine frühzeitige Diagnosestellung ist erforderlich, um der Entwicklung von Fehlanpassungen entgegenzuwirken.

Isolated Fracture of the posterolateral tibial lip (Volkmann's triangle)

Purpose: to retrospectively evaluate the underlying pathomechanism of isolated fracture of the posterolateral tibial lip (Volkmann's triangle), and to demonstrate associated radiographic methods.

Material and Methods: Retrospective analysis of 2500 ankle lesions showed an isolated fracture of the dorsal tibial lip in 25 cases. Distal tibial lesions of growing individuals were not considered. All patients were examined by radiography in internal oblique and lateral views.

Results: Sixteen of 25 patients had had their accident during winter; 11 had slipped on ice or snow. All 25 patients showed a closed ankle lesion in the correct joint position with no clinical signs of instability. Evaluation of the standard images showed isolated fracture of the posterolateral tibial lip in 24 patients. the fracture was best recognized in the standard lateral view in 22 patients. in 2 patients the lateral stress projection demonstrated the fracture (20° internal rotation). in one case the fracture was only seen on axial CT images. Twenty-two patients with small wedge fragments were treated conservatively; 3 with a displaced and large fragment had surgical revision and stabilization. Sixteen cases were examined by conventional radiography at follow-up examination and 5 of these showed radiological signs of arthrosis.

Conclusion: Plain conventional radiography is still necessary in the primary diagnosis of ankle joint lesions. the isolated fracture of the dorsal tibial margin is best seen in the standard lateral view. Indication for CT in routine diagnostics is limited to cases showing clinical evidence of ankle injury without roentgenological signs of a fracture in the standard images. Differential diagnoses include the pilon lesion and the Maison-neuve-type fracture.

Experimental realization of a polarization-independent ultraviolet/visible coaxial plasmonic metamaterial

We report the experimental realization of an optical metamaterial composed of a hexagonal array of coaxial plasmonic metal/insulator/metal waveguides that shows strong polarization-independent optical mode index dispersion in the ultraviolet/blue. The metamaterial is composed of silicon coaxes with a well-defined diameter in the range of 150-168 nm with extremely thin sidewalls (13-15 nm), embedded in a silver film, fabricated using a combination of electron beam lithography, physical vapor deposition, reactive ion etching, and focused ion beam polishing. Using a Mach-Zehnder interferometer the phase advance is measured on several metamaterial samples with different dimensions in the UV/visible part of the spectrum. For all geometries the spectral features as well as the geometry dependence of the data correspond well with numerical finite-difference time domain simulations and the calculated waveguide dispersion diagram, showing a negative mode index between 440 and 500 nm.

Crustal evolution, intra-cratonic architecture and the metallogeny of an Archaean craton

The generation of the Earth's continental crust modified the composition of the mantle and provided a stable, buoyant reservoir capable of capturing mantle material and ultimately preserving ore deposits. Within the continental crust, lithospheric architecture and associated cratonic margins are a first-order control on camp-scale mineralization. Here we show that the evolving crustal architecture of the Archaean Yilgarn Craton, Western Australia, played a key role in controlling the localization of camp-scale gold, iron and nickel mineralized systems. The age and source characteristics of Archaean lithosphere are heterogeneous in both space and time and are recorded by the varying Nd isotopic signature of crustal rocks. Spatial and temporal variations in isotopic character document the evolution of an intra-cratonic architecture through time, and in doing so map transient lithospheric discontinuities where gold, nickel and iron mineral systems were concentrated. Komatiite-hosted nickel deposits cluster into camps localized within young, juvenile crust at the isotopic margin with older lithosphere; orogenic gold systems are typically localized along major structures within juvenile crust; and banded iron formation (BIF)-hosted iron deposits are localized at the edge of, and within, older lithospheric blocks. Furthermore, this work shows that crustal evolution plays an important role in the development and localization of favourable sources of nickel, gold and iron by controlling the occurrence of thick BIFs, ultramafic lavas and fertile (juvenile) crust, respectively. Fundamentally, this study demonstrates that the lithospheric architecture of a craton can be effectively imaged by isotopic techniques and used to identify regions prospective for camp-scale mineralization.

An overview of immunosuppressive therapy in idiopathic membranous nephropathy

Idiopathic membranous nephropathy is the most common cause of nephrotic syndrome. In patients who present with nephrotic range proteinuria the clinical course is variable, with 50% of patients developing end stage renal disease after extended follow-up without therapy. We review the various immunosuppressive treatment modalities. The efficacy of alkylating agents is demonstrated in randomized trials, although side effects are a major drawback. Calcineurin inhibitors, rituximab and possibly adrenocorticotropic hormone (ACTH) are able to induce remission of proteinuria, which portends a good prognosis. However, the efficacy of these agents must be confirmed in randomized trials with adequate renal end points. Immunosuppressive treatment should be restricted to high risk patients. The use of immunosuppressive therapy has improved outcome of patients with iMN, with nowadays less than 10% of patients progressing to end stage renal disease (ESRD).

[MR imaging of the Achilles tendon: evaluation of criteria for the differentiation of asymptomatic and symptomatic tendons]

PURPOSE

The purpose of this study was to develop quantitative and qualitative MRI criteria to differentiate between healthy and pathological Achilles tendons.

MATERIALS AND METHODS

364 Achilles tendons were examined on a 1.5 T MRI scanner. 264 patients had Achilles tendon complaints, 100 asymptomatic Achilles tendons served as a control. T 1-weighted, T 2-weighted and a STIR sequence were performed in sagittal and axial orientation. Images were evaluated in consensus by two radiologists. Quantitative and qualitative criteria were assessed. A Mann-Whitney-U-Test and a regression analysis were used for statistical analysis.

RESULTS

There were statistically significant differences between the patients with disorders and the control group concerning the depth (12.0 mm and 6.3 mm, p < 0.001) and length (83.2 mm and 45.9 mm, p < 0.001) of the tendon, the area of the tendon cross section (1.60 mm (2) and 061 mm (2), p < 0.001), as well as the length of the bursa retrocalcanea (8.3 mm and 5.3 mm, p < 0.001). There was a sensitivity of 97 % and a specificity of 91 % using a formula including the 3 criteria: tendon depth (A4), length of bursa (A5) and area of tendon (F).

CONCLUSION

The measurement of the Achilles tendon and the binary-logistic regression analysis allow differentiation between normal and pathological Achilles tendons.

Asymmetric dimethylarginine as an independent risk marker for mortality in ambulatory patients with peripheral arterial disease

BACKGROUND

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide (NO) synthesis causing endothelial dysfunction, an early sign of atherogenesis. Symmetric dimethylarginine (SDMA) does not inhibit NO synthases. Peripheral arterial disease (PAD) is a systemic indication of atherosclerosis.

METHODS

We assessed the associations between both ADMA and SDMA blood levels and major cardiovascular and cerebrovascular events or death from any cause within a 5-year follow-up in the multicentre getABI trial. From a cohort of 6821 primary care patients, aged ≥65 years, all 1260 patients with prevalent PAD were compared with a random sample of 1187 non-PAD controls. A total of 11,544 patient-years were documented. Multivariate risks were calculated by Cox proportional hazard models, adjusting for PAD, renal dysfunction and other important cardiovascular risk factors.

RESULTS

We documented 390 deaths, 296 cardiovascular events and 98 cerebrovascular events. Increased ADMA levels in the 4th quartile were significantly associated with total mortality [hazard ratio (HR) 1.41; 95% CI 1.14-1.74] and with cardiovascular events (HR 1.32; 95% CI 1.03-1.69), but there was a nonsignificant association with cerebrovascular events (HR 1.50; 95% CI 0.98-2.29). Increased SDMA was only just significantly associated with mortality (HR 1.27; 95% CI 1.01-1.59). In PAD patients compared with non-PAD controls, only mean SDMA concentration was considerably increased (0.52 μmol L(-1) vs. 0.48 μmol L(-1); P < 0.001) mainly because of a highly significant association with impaired renal function.

CONCLUSION

These data suggest that ADMA but not SDMA is an independent risk marker for death from any cause or from cardiovascular events. The association between SDMA and mortality is in part explained by a close link between SDMA and renal function.

Vaccination with a soluble recombinant hemagglutinin trimer protects pigs against a challenge with pandemic (H1N1) 2009 influenza virus

In 2009 a new influenza A/H1N1 virus strain ("pandemic (H1N1) 2009", H1N1v) emerged that rapidly spread around the world. The virus is suspected to have originated in swine through reassortment and to have subsequently crossed the species-barrier towards humans. Several cases of reintroduction into pigs have since been reported, which could possibly create a reservoir for human exposure or ultimately become endemic in the pig population with similar clinical disease problems as current swine influenza strains. A soluble trimer of hemagglutinin (HA), derived from the H1N1v, was used as a vaccine in pigs to investigate the extent to which this vaccine would be able to protect pigs against infection with the H1N1v influenza strain, especially with respect to reducing virus replication and excretion. In a group of unvaccinated control pigs, no clinical symptoms were observed, but (histo)pathological changes consistent with an influenza infection were found on days 1 and 3 after inoculation. Live virus was isolated from the upper and lower respiratory tract, with titres up to 10(6) TCID(50) per gram of tissue. Furthermore, live virus was detected in brain samples. Control pigs were shedding live virus for up to 6 days after infection, with titres of up to 10(5) TCID(50) per nasal or oropharyngeal swab. The soluble H1N1v HA trimer diminished virus replication and excretion after a double vaccination and subsequent challenge. Live virus could not be detected in any of the samples taken from the vaccinated pigs. Vaccines based on soluble HA trimers provide an attractive alternative to the current inactivated vaccines.

Redox-generated isoprostanes are associated with residual platelet activity in aspirin-treated patients with stable coronary heart disease

AIM

Insufficient platelet inhibition by low-dose aspirin is associated with poor prognosis in patients with coronary heart disease (CHD). We sought to investigate the prevalence of this phenomenon in patients with stable CHD and to study whether oxidative stress plays a role in its pathogenesis.

METHODS AND RESULTS

We studied the platelet response to long-term (≥ 6 months) low-dose (100 mg per day) aspirin in 130 consecutive patients with stable CHD (age 66 ± 8 years, 83% male). Among a wide distribution of platelet responses to collagen, ADP, and arachidonic acid, the vast majority of patients in the highest tertile of residual platelet activity (defined as 'aspirin low-responders') were characterized by lack of platelet inhibition by aspirin in vitro, significantly although not completely suppressed platelet TXB₂ production and COX-1 activity, and significantly higher urinary 8-iso-prostaglandin F(2α) excretion [186 (147-230) vs. 230 (188-318) pg per mg creatinine; median (IQR), P < 0.001; measured by GC-MS].

CONCLUSION

A relevant proportion of patients with CHD show insufficient platelet inhibition by low-dose aspirin. Oxidative stress and lipid peroxidation causing isoprostane formation may underlie inadequate platelet inhibition in an aspirin-insensitive manner in patients with cardiovascular disease.

Second and subsequent recurrences of osteosarcoma: presentation, treatment, and outcomes of 249 consecutive cooperative osteosarcoma study group patients

PURPOSE

To evaluate patient and tumor characteristics, treatment, and outcomes in a large cohort of unselected patients with second and subsequent recurrences of osteosarcoma.

PATIENTS AND METHODS

Two hundred forty-nine consecutive patients who had originally received combined-modality therapy on neoadjuvant Cooperative Osteosarcoma Study Group protocols and went on to develop a total of 409 second and subsequent osteosarcoma recurrences were analyzed for patient-, tumor-, and treatment-related factors and outcomes.

RESULTS

Five-year overall and event-free survival rates were 16% and 9% for 249 second, 14% and 0% for 93 third, 13% and 6% for 38 fourth, and 18% and 0% for 14 fifth recurrences, respectively. The proportion of recurrences confined to the lungs decreased and the proportion of those with chest wall involvement increased with increasing numbers of recurrences. The duration of relapse-free intervals and the number of lesions at recurrence correlated with outcomes. While only one of 205 patients with rerecurrence survived past 5 years without surgical remission, 5-year overall and event-free survival rates were 32% and 18% for 119 second, 26% and 0% for 45 third, 28% and 13% for 20 fourth, and 53% and 0% for five fifth recurrences, respectively, in which a renewed surgical remission was achieved. The use of chemotherapy correlated with longer survival in patients without surgical remissions.

CONCLUSION

To our knowledge, this is the first report of survival estimates derived from large cohorts of unselected patients with second and subsequent osteosarcoma recurrences. It confirms the overwhelming importance of surgical clearance. Prognostic indicators after rerecurrences resemble those known from first recurrence. The exact role of re-treatment with chemotherapy, particularly in the adjuvant situation, remains to be defined.

Rapid development of severe end-organ damage in C57BL/6 mice by combining DOCA salt and angiotensin II

The C57BL/6 mouse strain serves as the genetic background of many transgenic and gene knockout models; however, this strain appears to be resistant to hypertension-induced renal injury. We developed a new model of hypertensive end-organ damage in C57BL/6 mice by combining deoxycorticosterone acetate (DOCA) and salt with angiotensin II infusion. The systolic blood pressure (SBP) was significantly elevated in DOCA salt-angiotensin II mice compared to control mice or mice treated individually with DOCA salt or angiotensin II. Hypertensive glomerular damage, increased expression of profibrotic and inflammatory genes, albuminuria, tubular casts, increased plasma cholesterol, cardiac hypertrophy, and fibrosis were found in mice treated with DOCA salt-angiotensin II. The SBP in the angiotensin II-infused group was further increased by increasing the infusion rate; only mild injury was observed in these mice, suggesting that blood pressure was not a causal factor. Removal of DOCA and the angiotensin pump lowered blood pressure to normal; however, albuminuria along with the glomerular and cardiac damage did not completely resolve. Our study describes a new model of hypertensive end-organ damage and repair in C57BL/6 mice.

[Palliation in patients with metastatic breast cancer often better with antitumour treatment than with only symptomatic treatment]

Two women, aged 57 and 55 years, with metastatic breast cancer were admitted for uncontrolled pain due to bone metastases. Despite the fact that progressive disease was evident, a change in antitumour therapy had not been recommended. The pain control was optimised in both patients. In one patient, palliative chemotherapy was installed, combined with trastuzumab because of HER2/neu overexpression. She was still alive after one and a half year of treatment. The other patient could not adjust mentally to the fact that her palliative therapy was changed to antitumour therapy; she died one month later. It is important to be aware of the various kinds of therapy in metastatic breast cancer because palliative treatment is more than just symptomatic treatment. Systemic antitumour therapy includes hormone therapy, chemotherapy and targeted therapy. Furthermore, in patients with bone metastases, radiotherapy combined with bisphosphonates results in pain relief and can reduce skeletal complications. Because of the ensuing complexity of the treatment of metastatic breast cancer, these patients should be regularly managed by a breast-cancer care team in order to improve the quality of care.

Computational modeling of arterial wall growth. Attempts towards patient-specific simulations based on computer tomography

The present manuscript documents our first experiences with a computational model for stress-induced arterial wall growth and in-stent restenosis related to atherosclerosis. The underlying theoretical framework is provided by the kinematics of finite growth combined with open system thermodynamics. The computational simulation is embedded in a finite element approach in which growth is essentially captured by a single scalar-valued growth factor introduced as internal variable on the integration point level. The conceptual simplicity of the model enables its straightforward implementation into standard commercial finite element codes. Qualitative studies of stress-induced changes of the arterial wall thickness in response to balloon angioplasty or stenting are presented to illustrate the features of the suggested growth model. First attempts towards a patient-specific simulation based on realistic artery morphologies generated from computer tomography data are discussed.

Skip metastases in osteosarcoma: experience of the Cooperative Osteosarcoma Study Group

PURPOSE

The outlook for patients with osteosarcoma who present with synchronous regional bone metastases (skip metastases), either in the primary bone site or transarticular, is considered to be extremely poor. This study was conducted to further investigate the prognostic implication of skip metastases in osteosarcoma.

PATIENTS AND METHODS

The authors retrospectively analyzed the collected data of 1,765 consecutive patients with newly diagnosed high-grade osteosarcoma of bone who were registered in the neoadjuvant Cooperative Osteosarcoma Study Group studies and identified 24 patients (1.4%) with unequivocally proven skip metastases. All 24 patients were treated by an aggressive surgical approach coupled with polychemotherapy. Demographic, diagnostic, tumor, and treatment-related variables and response and survival data were analyzed.

RESULTS

Skip metastases were identified preoperatively in 11 of 24 patients by bone scan, eight of 22 patients by plain x-ray, 15 of 18 patients by magnetic resonance imaging, and five of 10 patients by computed tomography. A complete surgical remission (CSR) of all clinically detectable tumor sites was achieved in 22 of 24 patients during front-line therapy. With a median follow-up time of 4.4 years (8 years for survivors) from diagnosis, 12 patients were alive, all of whom were in continuous CSR. Survival did correlate with location of skip metastases and histologic response to neoadjuvant chemotherapy.

CONCLUSION

Synchronous regional bone metastases are rare in osteosarcoma, and preoperative detection relies on appropriate diagnostic imaging. Aggressive multimodal therapy holds the promise to achieve prolonged survival, especially in patients in whom these metastases occur within the same bone as the primary lesion and whose tumors respond well to chemotherapy.

Determination of a reference value for N(G), N(G)-dimethyl-L-arginine in 500 subjects

BACKGROUND

Asymmetric dimethylarginine (ADMA) acts as an endogenous inhibitor of NO-synthase. In the last years ADMA has emerged as a cardiovascular risk factor. The aim of this study was to determine a reference value for ADMA.

METHODS

Plasma samples of 500 healthy subjects in the 19-75 year age group were analyzed. Exclusion criteria from this study were smoking, any known significant disease, body-mass-index (BMI) above 30 kg m(-2), elevated plasma lipid levels, impaired renal function, hypertension, and intake of any medication. The ADMA levels were determined by ELISA, (DLD Diagnostics, Hamburg, Germany).

RESULTS

Mean ADMA plasma concentration of the total population was 0.69 micromol L(-1) (SD 0.20) and 95% of the measured values were in the range from 0.36 micromol L(-1) to 1.17 micromol L(-1). Women below 50 years of age had lower ADMA levels than men below 50 years of age [0.62 (0.17) micromol L(-1) vs. 0.69 (0.19) micromol L(-1); P = 0.001] and woman above 50 years of age had higher ADMA levels than men above 50 years of age [0.80 (0.22) micromol L(-1) vs. 0.73 (0.20) micromol L(-1); P = 0.036]. A regression analysis of ADMA levels and age was performed for each sex. The regression factor was r = 0.444 for women in a squared regression model (P < 0.001) and r = 0.212 for men in a linear regression model (P < 0.001).

CONCLUSION

The study was able to define a reference value for ADMA plasma levels with 0.36-1.17 micromol L(-1) and found sex dependent correlations between ADMA and age. Women showed a significant increase in ADMA plasma levels with onset of menopause.

[Biomarkers as prognostic factors in pulmonary arterial hypertension. Rationale and study design]

CURRENT SITUATION

Pulmonary arterial hypertension (PAH) is a serious disease. Its prognostic is based on the functional status quantified by the NYHA class and the 6-min walking test, and the hemodynamic data. The algorithms of treatment are solely based on the hemodynamic data and the functional status. The main objective is to test whether basal concentrations of isoprostanes, Big endotheline 1, ADMA, high sensitivity CRP, NT-Pro-BNP and cardiac troponin T are a 3-year prognostic factor in PAH using a combined criterion: death from any cause and pulmonary or cardiopulmonary transplantation.

MATERIALS AND METHODS

This is a multicenter, prospective, prognostic, single blinded study (plasma and urinary samples being blinded). The study started in november 2003, running for 2 years, with a 3 year follow-up for each patient. The main inclusion criterion is PAH. The data analysis will use a multivariable Cox model, taking into account the functional and hemodynamic parameters.

EXPECTED RESULTS

This study will determine whether any of the biomarkers tested provides additional prognostic information in PAH in addition to the functional and hemodynamic parameters.

Osteosarcoma relapse after combined modality therapy: an analysis of unselected patients in the Cooperative Osteosarcoma Study Group (COSS)

PURPOSE

To evaluate the impact of patient, tumor, and treatment-related factors on outcome in unselected patients with recurrent osteosarcoma.

PATIENTS AND METHODS

Five hundred seventy-six consecutive patients who had achieved a first complete surgical remission (CR) during combined-modality therapy on neoadjuvant Cooperative Osteosarcoma Study Group (COSS) protocols and then developed recurrent osteosarcoma were analyzed (median time from biopsy to relapse, 1.6 years; range, 0.1 to 14.3 years). There were 501 patients with metastases, 44 with local recurrences, and 31 with both. Metastases involved lungs (469 patients), bones (90 patients), and/or other sites (54 patients).

RESULTS

After a median follow-up of 1.2 years for all patients and 4.2 years for survivors, actuarial overall survival (OS) rates at 2, 5, and 10 years were 0.38, 0.23, and 0.18, respectively. Five-year OS was 0.39 for 339 patients with and 0.00 for 229 patients without a second surgical CR (P < .0001). A long time to relapse, a solitary lesion, and, in the case of pulmonary metastases, unilateral disease and the absence of pleural disruption, were of positive prognostic value in uni- and multivariate analyses, as were a second surgical CR and the use of second-line chemotherapy. Radiotherapy was associated with moderately prolonged survival in patients without a second CR. The very limited prognostic differences associated with the use of second-line chemotherapy appeared to be more pronounced with polychemotherapy.

CONCLUSION

Time to relapse and tumor burden correlate with postrelapse outcome in osteosarcoma. Complete surgery is an essential component of curative second-line therapy. Chemotherapy, particularly chemotherapy with more than one agent, may contribute to limited improvements in outcome.

Validation study to evaluate the reproducibility of a candidate in vitro potency assay of newcastle disease vaccines and to establish the suitability of a candidate biological reference preparation

A quantification assay for the Haemagglutinin-Neuraminidase (HN) protein of Newcastle Disease Virus (NDV) has been developed at CIDC-Lelystad as a candidate in vitro potency test for inactivated Newcastle disease (ND) vaccines. In studies performed at CIDC-Lelystad, a high correlation was demonstrated between the results of this candidate in vitro potency assay and the results of the serological potency assay (European Pharmacopoeia monograph 0870; test A). Furthermore, a high correlation between the serological data (Haemagglutination Inhibition-antibody titres) and clinical protection after challenge was demonstrated. Correlation between in vivo and in vitro potency assays was confirmed in a collaborative pre-validation study. In the pre-validation study three Official Medicines Control Laboratories (OMCLs) determined both the NDV-HN antigen content and the in vivo potency (vaccination-serology and vaccination-challenge) of 6 vaccine batches. The conclusion of the pre-validation study was that a large-scale collaborative study should be organised to validate the in vitro method and the suitability of the reference preparation. This report describes the outcome of this study. In brief, 14 laboratories (8 OMCLs and 6 vaccine manufacturers) determined the NDV-HN antigen content of 9 different vaccines in 3 independent tests. The vaccine batches were produced by 5 different manufacturers and represent a quantitative range of ND antigen content. One vaccine batch with insufficient potency and one poultry vaccine not containing NDV were included. Statistical evaluation of the results indicated that the antigen content could be determined with high precision. A good repeatability as well as reproducibility was found. Furthermore all laboratories found a similar ranking of the vaccines, based on the antigen content. Comparison of the antigen content and the in vivo potency of a series of vaccines with relatively low potencies indicated that a threshold relative antigen level of 7.0 antigen units per dose would discriminate between vaccine batches with sufficient and insufficient potency. An in vitro assay with this threshold level for antigen content did not result in any false positive results and only a limited number of false negative results in the BSP055 study. We conclude that the in vitro measurement of the antigen content of inactivated ND-vaccines with the proposed method is a reliable alternative potency assay that could be included as a new method in monograph 0870 on ND-vaccines.

Validation of a candidate in vitro potency assay for inactivated Newcastle disease vaccines

An NDV-HN antigen quantification assay has been developed as a candidate in vitro batch potency assay for inactivated vaccines. The assay consists of extraction of the viral antigens from the oil emulsion vaccines and quantification of the NDV-HN in a DAS-EUSA. After optimisation and preliminary validation, large stocks of lyophilised test reagents were prepared. Stability studies showed that there was no decrease in reactivity of the reagents in one year at -20 degrees after lyophilisation. Also in accelerated stability studies no decrease in reactivity was found after storage at higher temperatures. Antigen recovery, accuracy of the assay and specificity of the assay were found to be satisfactory in an in-house validation study. The intermediate precision was good to very good with coefficient of variation (CV) values that were always below 15%. The transferability of the test protocols has been studied in a pre-validation study in which three laboratories from two different countries participated. The protocols and the assay could be transferred to other laboratories without difficulty. Furthermore, vaccines with low and high potency as well as negative controls were identified by all participants. Finally between-assay as well as between-laboratory variation was satisfactory with CV-values of 0 to 30.

Antigen content of inactivated Newcastle disease oil emulsion vaccines as an in vitro indicator of potency

The potency of each batch of inactivated Newcastle disease virus (NDV) vaccine is measured in either a vaccination-serology or a vaccination-challenge experiment. We have developed an antigen quantification assay as an in vitro alternative for these currently prescribed in vivo potency assays. The in vitro assay consists of extraction of the viral antigens from the oil emulsion vaccines by isopropylmyristate, followed by quantification of the NDV HN-antigen in an ELISA. The analysis of 20 inactivated vaccines, representing the most common NDV-vaccines in Western Europe, indicated that large differences in antigen content exist between these vaccines. A comparison of the antigen content with the serological response after vaccination with 1/50 vaccine dose demonstrated that a reliable estimate of the potency can be made, based on the HN-antigen content of the vaccine. We therefore present our antigen quantification assay for NDV as a candidate in vitro potency assay. An international feasibility and validation study will be needed to prove the suitability and reliability of this candidate in vitro potency assay for inactivated NDV vaccines.