Agreement between BMI and body fat obesity definitions in a physically active population.

OBJECTIVES: Body mass index (BMI) is a widely used proxy of body composition (BC). Concerns exist regarding possible BMI misclassification among active populations. We compared the prevalence of obesity as categorized by BMI or by skinfold estimates of body fat percentage (BF%) in a physically active population. SUBJECTS AND METHODS: 3,822 military firefighters underwent a physical fitness evaluation including cardiorespiratory fitness (CRF) by the 12 min-Cooper test, abdominal strength by sit-up test (SUT) and body composition (BC) by BF% (as the reference), as well as BMI. Obesity was defined by BF% > 25% and BMI ≥ 30 kg/m2. Agreement was evaluated by sensitivity and specificity of BMI, positive and negative predictive values (PPV/NPV), positive and negative likelihood (LR+/LR-), receiver operating characteristic (ROC) curves and also across age, CRF and SUT subgroups. RESULTS: The prevalence of obesity estimated by BMI (13.3%) was similar to BF% (15.9%). Overall agreement was high (85.8%) and varied in different subgroups (75.3-94.5%). BMI underestimated the prevalence of obesity in all categories with high specificity (≥ 81.2%) and low sensitivity (≤ 67.0). All indices were affected by CRF, age and SUT, with better sensitivity, NPV and LR- in the less fit and older groups; and higher specificity, PPV and LR+ among the fittest and youngest groups. ROC curves showed high area under the curve (≥ 0.77) except for subjects with CRF ≥ 14 METs (= 0.46). CONCLUSION: Both measures yielded similar obesity prevalences, with high agreement. BMI did not overestimate obesity prevalence. BMI ≥ 30 was highly specific to exclude obesity. Because of systematic under estimation, a lower BMI cut-off point might be considered in this population.

Agreement between BMI and body fat obesity definitions in a physically active population

ABSTRACT Objectives Body mass index (BMI) is a widely used proxy of body composition (BC). Concerns exist regarding possible BMI misclassification among active populations. We compared the prevalence of obesity as categorized by BMI or by skinfold estimates of body fat percentage (BF%) in a physically active population. Subjects and methods 3,822 military firefighters underwent a physical fitness evaluation including cardiorespiratory fitness (CRF) by the 12 min-Cooper test, abdominal strength by sit-up test (SUT) and body composition (BC) by BF% (as the reference), as well as BMI. Obesity was defined by BF% > 25% and BMI ≥ 30 kg/m2. Agreement was evaluated by sensitivity and specificity of BMI, positive and negative predictive values (PPV/NPV), positive and negative likelihood (LR+/LR-), receiver operating characteristic (ROC) curves and also across age, CRF and SUT subgroups. Results The prevalence of obesity estimated by BMI (13.3%) was similar to BF% (15.9%). Overall agreement was high (85.8%) and varied in different subgroups (75.3-94.5%). BMI underestimated the prevalence of obesity in all categories with high specificity (≥ 81.2%) and low sensitivity (≤ 67.0). All indices were affected by CRF, age and SUT, with better sensitivity, NPV and LR- in the less fit and older groups; and higher specificity, PPV and LR+ among the fittest and youngest groups. ROC curves showed high area under the curve (≥ 0.77) except for subjects with CRF ≥ 14 METs (= 0.46). Conclusion Both measures yielded similar obesity prevalences, with high agreement. BMI did not overestimate obesity prevalence. BMI ≥ 30 was highly specific to exclude obesity. Because of systematic under estimation, a lower BMI cut-off point might be considered in this population.

Magnetic anisotropy of endohedral lanthanide ions: paramagnetic NMR study of MSc2N@C80-Ih with M running through the whole 4f row.

Paramagnetic and variable temperature 13C and 45Sc nuclear magnetic resonance studies are performed for nitride clusterfullerenes MSc2N@C80 with icosahedral Ih(7) carbon cage, where M runs through all lanthanides forming nitride clusters. The influence of the endohedral lanthanide ions on the NMR spectral pattern is carefully followed, and dramatic differences are found in peak positions and line widths. Thus, 13C lines broaden from 0.01-0.02 ppm in diamagnetic MSc2N@C80 molecules (M = La, Y, Lu) to several ppm in TbSc2N@C80 and DySc2N@C80. Direction of the paramagnetic shift depends on the shape of the 4f electron density in corresponding lanthanide ions. In TmSc2N@C80 and ErSc2N@C80 with prolate 4f-density of lanthanide ions, 13C signals are shifted down-field, whereas 45Sc peaks are shifted up-field versus diamagnetic values. In all other MSc2N@C80 molecules lanthanide ions have oblate-shaped 4f electron density, and the lanthanide-induced shift is negative for 13C and positive for 45Sc peaks. Analysis of the pseudocontact and contact contributions to chemical shifts revealed that the pseudocontact term dominates both in 13C and 45Sc NMR spectra, although contact shifts for 13C signals are also considerable. Point charge computations of the ligand field splitting are performed to explain experimental results, and showed reasonable agreement with experimental pseudocontact shifts. Nitrogen atom bearing large negative charge and located close to the lanthanide ion results in large magnetic anisotropy of lanthanide ions in nitride clusterfullerenes with quasi-uniaxial ligand field.

Cluster-size dependent internal dynamics and magnetic anisotropy of Ho ions in HoM2N@C80 and Ho2MN@C80 families (M = Sc, Lu, Y).

The paramagnetic NMR study of HoM2N@C80-Ih and Ho2MN@C80-Ih nitride cluster fullerenes (M = Sc, Lu, Y) reveals strong dependence of Ho-induced paramagnetic shifts (δ(para)) in (13)C NMR spectra on the size of the diamagnetic metal in the cluster. In particular, the δ(para) value in HoY2N@C80 is almost doubled in comparison to that in HoSc2N@C80. X-ray magnetic circular dichroism studies show that all Ho-nitride cluster fullerenes have the same magnetic ground state of Ho(3+). Point-charge ligand-field splitting calculations show that the increase of the M(3+) radius in going from Sc to Y results in a considerable increase of the energy splitting between different Jz states. This leads to a 19% higher magnetic anisotropy of Ho(3+) in HoY2N@C80 than in HoSc2N@C80 at 300 K. Variations of the molecular geometry and cluster dynamics with the size of the cluster are found to have even greater influence on δ(para) values. This work shows that the magnetic properties of the species confined inside the fullerene cages can be tuned using the geometrical factors such as the cluster and the cage size.

Biogenic volatile emissions from the soil.

Volatile compounds are usually associated with an appearance/presence in the atmosphere. Recent advances, however, indicated that the soil is a huge reservoir and source of biogenic volatile organic compounds (bVOCs), which are formed from decomposing litter and dead organic material or are synthesized by underground living organism or organs and tissues of plants. This review summarizes the scarce available data on the exchange of VOCs between soil and atmosphere and the features of the soil and particle structure allowing diffusion of volatiles in the soil, which is the prerequisite for biological VOC-based interactions. In fact, soil may function either as a sink or as a source of bVOCs. Soil VOC emissions to the atmosphere are often 1-2 (0-3) orders of magnitude lower than those from aboveground vegetation. Microorganisms and the plant root system are the major sources for bVOCs. The current methodology to detect belowground volatiles is described as well as the metabolic capabilities resulting in the wealth of microbial and root VOC emissions. Furthermore, VOC profiles are discussed as non-destructive fingerprints for the detection of organisms. In the last chapter, belowground volatile-based bi- and multi-trophic interactions between microorganisms, plants and invertebrates in the soil are discussed.

Isoprene function in two contrasting poplars under salt and sunflecks.

In the present study, biogenic volatile organic compound (BVOC) emissions and photosynthetic gas exchange of salt-sensitive (Populus x canescens (Aiton) Sm.) and salt-tolerant (Populus euphratica Oliv.) isoprene-emitting and non-isoprene-emitting poplars were examined under controlled high-salinity and high-temperature and -light episode ('sunfleck') treatments. Combined treatment with salt and sunflecks led to an increased isoprene emission capacity in both poplar species, although the photosynthetic performance of P. × canescens was reduced. Indeed, different allocations of isoprene precursors between the cytosol and the chloroplast in the two species were uncovered by means of (13)CO2 labeling. Populus × canescens leaves, moreover, increased their use of 'alternative' carbon (C) sources in comparison with recently fixed C for isoprene biosynthesis under salinity. Our studies show, however, that isoprene itself does not have a function in poplar survival under salt stress: the non-isoprene-emitting leaves showed only a slightly decreased photosynthetic performance compared with wild type under salt treatment. Lipid composition analysis revealed differences in the double bond index between the isoprene-emitting and non-isoprene-emitting poplars. Four clear metabolomics patterns were recognized, reflecting systemic changes in flavonoids, sterols and C fixation metabolites due to the lack/presence of isoprene and the absence/presence of salt stress. The studies were complemented by long-term temperature stress experiments, which revealed the thermotolerance role of isoprene as the non-isoprene-emitting leaves collapsed under high temperature, releasing a burst of BVOCs. Engineered plants with a low isoprene emission potential might therefore not be capable of resisting high-temperature episodes.

New ischemic brain lesions after carotid artery stenting.

Carotid artery stenting is associated with the risk of periprocedural stroke. Moreover, modern magnetic resonance (MR) imaging techniques have found high rates of clinically silent ischemic brain lesions on post-treatment diffusion-weighted MR imaging (DWI) scans. The clinical significance of procedure-related DWI lesions, however, is still a matter of debate. This review article considers the frequency, location and pathophysiology of new DWI lesions on post-treatment MR images and summarizes available data on their clinical significance.

Impact of protein content on proton diffusibility in intracranial cysts.

PURPOSE: The physical background of diffusion phenomena in intracranial cysts is unclear in some cases. To evaluate a potential dependency of proton diffusion on the concentration of proteins in cystic lesions we investigated the correlation of diffusion weighted imaging (DWI) and magnetization transfer ratio imaging (MTR) in intracranial cystic pathologies in vivo and in vitro with protein solutions. MATERIALS AND METHODS: 21 patients (14 male/7 female) with intracranial cystic lesions underwent preoperative MRI (1.5T) including MTR and DWI sequences. For comparison a series of samples with declining concentration of albumin was investigated in vitro with a 7T animal scanner. RESULTS: In the patients examination mean ADC values were 1.93×10-3mm2/sec and mean MTR values were 0.2. Mean ADC value of the albumin solutions was 0.22× 0-3mm2/sec and mean MTR was 0.12. ADC and MTR values showed a strong negative correlation in the patients (Spearman's rank correlation rs=-0.80, p<0.01) and a very strong negative correlation in the in vitro examinations (rs=-1.0, p<0.01). CONCLUSION: The strong negative correlation of ADC and MTR values suggest a strong influence of proteins on proton diffusion in intracranial cysts. The phenomena can be explained by macromolecules that bind nearby protons in their vicinity.

Quantitative t2 measurements in juvenile and late infantile neuronal ceroid lipofuscinosis.

PURPOSE: The two most prevalent forms of neuronal ceroid lipofuscinosis (NCL) are the juvenile form (Batten disease, CLN3) and late infantile form (Jansky-Bielschowsky disease, CLN2). The aim of this study was to compare quantitative T2-values of brain tissue in CLN2 and CLN3 patients with reference values from age-matched normal subjects. METHODS: Twenty-three CLN2 (n = 6) and CLN3 (n = 17) patients (m:f = 11:12) underwent MRI examination including a multiecho T2 sequence. Quantitative T2-values were measured in six defined regions of interest (ROIs) in the calculated quantitative T2 maps within the white matter (WM) and gray matter (GM). The extracted quantitative T2-values were compared with reference values from healthy children and young adults. Informed consent was obtained from the patients or their parents for all patients. RESULTS: Statistical analysis revealed elevated quantitative T2-values in nearly all ROIs placed in the WM of the CLN2 patients. In contrast to this finding, no significant differences were found for the quantitative T2-values of the CLN3 patients compared to the age-matched healthy controls in any of the defined WM ROIs. Both groups exhibited no significant alterations of the quantitative T2-values in the GM ROIs compared to the healthy subjects. CONCLUSION: Alterations of quantitative T2-values in the cerebral WM may not be a reliable sign to confirm the diagnosis in CLN3 patients but could prove valuable for diagnosis confirmation, follow-up examinations, and longitudinal monitoring of the disease progression in CLN2 patients.

Thrombolysis targeting MRI defined tissue at risk in minor stroke.

BACKGROUND: Treatment with intravenous tissue plasminogen activator (IV-tPA) is usually not recommended in patients with minor stroke. Clinical and imaging outcome were studied after IV-tPA treatment based on MRI criteria in patients with minor stroke. METHODS: Data were analysed retrospectively of acute ischaemic stroke patients with minor stroke (National Institutes of Health Stroke Scale (NIHSS) score <4). All patients were studied by stroke MRI including perfusion and diffusion weighted imaging (PWI and DWI) and treated with IV-tPA for < or =6 h. Final infarct volume was delineated on follow-up MRI. Clinical outcome was assessed after 90 days using the modified Rankin Scale (mRS). RESULTS: Six patients with a median NIHSS on admission of 2 (range 0-3) were treated with IV-tPA based on MRI criteria. In all patients, occlusion of the middle cerebral artery (MCA) was detected (MCA branch n = 2, MCA trunk n = 3, MCA trifurcation n = 1), and the PWI lesion (41, 25-60 ml) exceeded the DWI lesion (4, 1-23 ml). Final infarct volume was 9 (2-29) ml. Favourable outcome (mRS 0-1) was seen in 5/6 patients and independent outcome (mRS = 2) in one patient. No intracerebral haemorrhages occurred. CONCLUSION: Treatment with IV-tPA based on MRI criteria was safe and appeared to be effective in this small series of patients with minor stroke.

[Long-term outcome after endovascular treatment of high-risk patients with recurrently symptomatic intracranial stenoses of the posterior circulation]. / Langzeitergebnisse nach endovaskulärer Behandlung von Hochrisiko-Patienten mit mehrfach symptomatischen intrakraniellen Stenosen der vertebrobasilären Strombahn.

PURPOSE: We present long-term clinical and duplex data from high-risk patients with severe, recurrent symptomatic stenoses of the vertebrobasilar circulation. We hypothesized that despite the greater risk of periprocedural complications in this patient group, interventional treatment would reduce the risk of recurrent strokes relative to the expected natural risk. We also predicted that the long-term treatment outcome would be positively influenced by the use of stents and by the periprocedural technical success rate. MATERIALS AND METHODS: An analysis of our patient data base yielded 45 cases of stenosis of the vertebrobasilar circulation treated endovascularly in 42 patients between 1998 and 2006. Clinical and vascular diagnostic tests, both periinterventionally and during follow-up, were performed independently by experienced neurologists. RESULTS: The technical success rate was 93%. Stents were used in 67% of the procedures. After 30 days, 24% of the patients showed post-procedural clinical deterioration. After an average period of 26.3 months, 17.8 % of the patients had deteriorated. 11.1% of the patients suffered severe permanent damage as a result of the procedure (mRs 3 - 6). Restenosis was found in 9.5% of the cases. There were no instances of a recurrent stroke during follow-up. CONCLUSION: For this population of high-risk patients with recurrently symptomatic intracranial stenoses of the vertebrobasilar axis, endovascular treatment reduced the risk of stroke and death relative to the expected natural risk. The use of stents had no significant effect on the long-term results.

Long-term outcome after angioplasty of symptomatic internal carotid artery stenosis with and without stent.

INTRODUCTION: Carotid angioplasty and stenting (CAS) has widely replaced balloon angioplasty (percutaneous transluminal angioplasty, PTA) in the treatment of internal carotid artery stenosis (ICAS). Here we assess whether the use of stents increases the safety and long-term efficacy of angioplasty in patients with ICAS. Our aim was to test the hypothesis that the long-term efficacy of CAS is superior to that of PTA. METHODS: At the University Medical Center Hamburg-Eppendorf, PTA was performed from 1990 to 1997 and CAS was performed from 1998 to 2006. All patients undergoing these procedures were symptomatic. Selection and follow-up examinations were performed by independent vascular neurologists. Follow-up terms were 1, 3, 6 and 12 months, then annually. RESULTS: In the PTA group (n=71), 2.8% of the patients showed severe periinterventional complications (i.e. lasting neurological deficits). Of these 71 patients, 57.7% were followed up for an average period of 51 months. Stenosis >70% was observed in 9.8% of the PTA patients, while 4.9% of the patients had ipsilateral occlusions. In the CAS group (n=354), 4.2% of the patients showed severe periinterventional complications. In total, 61% of the CAS patients were followed up for an average period of 25 months, of whom 4.6% showed stenosis of >70% and 1.9% had ipsilateral occlusions. Periprocedural complications and new symptoms that appeared during follow-up occurred at a rate of 5.6% (PTA) and 5.9% (CAS). There was no difference in the rate of annual ipsilateral events (1.1% in PTA vs. 1.3% in CAS, p=1.000) CONCLUSION: Overall, the use of stents, rather than PTA only, shows no beneficial clinical effect in the treatment of ICA stenosis. While the rate of restenosis may be significantly reduced, this merely suggests that the impact of restenosis is less apparent than expected.

Transcranial grey-scale sonography of subdural haematoma in adults.

AIM: Transcranial high-resolution grey-scale sonography reliably allows diagnosis and monitoring of subdural haematoma (SDH) and extra-cerebral intracranial fluid collections in infants but has not been evaluated thoroughly in adults up to now. Because of rapid development of ultrasound systems, the depiction of intracerebral haemorrhage (ICH) has now become feasible. The presented study evaluated the sonographic appearance of SDH in adults. METHOD: We performed transcranial grey-scale sonography (TGS) in 25 consecutive patients with SDH confirmed by cranial computed tomography (CCT) or MRI. According to paediatric TGS, the dural border of the arachnoid was depicted as a highly echogenic membrane, and the distance between the skull and the echogenic membrane was measured. SDH was measured by CCT/MRI and by TGS in corresponding axial planes. The rate of identification of SDH in TGS was evaluated, and the extent of SDH as assessed by CCT/MRI and TGS was compared. RESULTS: TGS reliably detected SDH in 22 of the 25 patients with confirmed SDH (88 %). In the remaining 3 patients, the temporal bone window was insufficient for TGS investigation. Extent of SDH measured by CCT and TGS correlated linearly (r= 0.849). CONCLUSION: TGS allows imaging of SDH in patients with CCT/MRI confirmed SDH, and the extent of SDH correlates significantly between TGS and CCT/MRI. Therefore, TGS may be a possible alternative to serial CCT imaging in monitoring SDH, since in contrast to CCT, TGS is a non-invasive bedside method. So far, TGS is not suitable for the diagnosis of SDH.

The amount of solid cerebral microemboli during carotid stenting does not relate to the frequency of silent ischemic lesions.

BACKGROUND AND PURPOSE: Carotid artery stent placement (CAS) may be associated with clinically silent cerebral lesions. We prospectively evaluated the association of the number of solid cerebral microemboli during unprotected CAS with the frequency of silent cerebral lesions as detected by diffusion-weighted MR imaging (DWI). METHODS: We performed multifrequency transcranial Doppler detection of solid microemboli in the ipsilateral middle cerebral artery (MCA) during CAS in 27 consecutive patients with symptomatic high-grade carotid stenoses. No embolus protection was used in any of the cases. DWI before and 24 +/- 2 hours after CAS was used to detect new ischemic lesions. RESULTS: We detected 484 solid microemboli in 17 patients (63%). On MR imaging 24 +/- 2 hours after CAS, 6 patients (22%) had developed 13 new clinically silent DWI lesions within the ipsilateral MCA territory. In patients with Doppler evidence of solid emboli during CAS, the incidence of new DWI lesions was higher (29%) than in patients without Doppler evidence of solid emboli during the procedure (10%); this difference was not statistically significant (P = .25). The number of solid microemboli during CAS in patients with new ipsilateral DWI lesions was not significantly different from that in patients without new ipsilateral DWI lesions. CONCLUSIONS: Solid microembolism is a common event during unprotected CAS; however, the frequency of procedure-related silent cerebral lesions appears to be independent of the number of solid cerebral microemboli during the procedure.

Plasma amino acids in ecstasy users.

Recreational use of the illegal drug "ecstasy" has increased dramatically in recent years. We have measured 33 different plasma amino acids in ecstasy users and controls. Significant differences were found for phosphoserine, glutamate, citrulline, methionine, tyrosine and histidine. Resembling changes in the plasma amino acids have been described in acute transient polymorphous psychosis. Thus, alterations in plasma - methionine and phosphoserine or other amino acids could be involved in the psychical symptoms produced by MDMA.

Plasma concentrations of 5-HT, 5-HIAA, norepinephrine, epinephrine and dopamine in ecstasy users.

Recreational use of the synthetic methamphetamine derivative MDMA (3,4-methylenedioxymethamphetamine), the main constituent of the illegal drug "ecstasy", has increased dramatically in recent years. The reasons for ecstasy-associated cardiovascular complications like tachycardia, arrhythmias and hypertensive crises and psychiatric symptoms like psychotic episodes are not well understood. We have measured the plasma concentrations of 5-HIAA, 5-HT, norepinephrine, epinephrine and dopamine in 159 ecstasy users and controls. Ecstasy users showed elevated resting sympathetic activity, reflected in increased norepinephrine, epinephrine and dopamine levels. The levels of these catecholamines correlated positively with the cumulative dose and also with consumption during the last 30 days and 12 months. Although it is known that significant changes in 5-HT and 5-HIAA appear in the cerebrospinal fluid in ecstasy users, we could not detect alterations in serotonergic neurotransmitters in plasma in this large sample of subjects. Thus, in the drug-free interval, ecstasy users show lowered central serotonergic activity (lowered 5-HT and 5-HIAA concentrations in CSF) along with unchanged central noradrenergic and dopaminergic activity (HVA and MHPG unchanged in CSF) and elevated peripheral noradrenergic, dopaminergic and adrenergic activity along with unchanged peripheral serotonergic activity (plasma levels). We conclude, that the data presented here could argue for a noradrenergic hyperreactivity in the drug-free interval in ecstasy users resulting from previous ecstasy consumption. Also for an association with psychotic episodes and cardiovascular complications like tachycardia, arrhythmias.

[A comparative study of cytological and histological studies of the thyroid gland]. / Vergleichende Untersuchung zytologischer und histologischer Befunde der Schilddrüse.

We compare the results of fine-needle aspiration cytology of the thyroid gland with postoperative histological findings in 533 patients with thyroidectomy operated on between 1987 and 1994. The classification of the cytological preparations followed the proposal of Weiss and Pilz [35] with the groups 0-IV. In group 0 the most frequent findings were cystic changes in multinodular goitre or malpuncture, respectively. The groups I and II contained cases with multinodular goitre, thyroiditis and follicular adenomas, but 4 carcinomas too. The group III comprised particularly follicular adenomas and carcinomas (8 cases). Both cases in group IV were carcinomas. In group III (cytologic group with suspicious findings) there were 65 cases with false positive results of the cytologic investigation resulting in a specificity of 86.4%. 4 out of 14 thyroid carcinomas could not be detected by cytologic preparations corresponding to a sensitivity of 71.4% for carcinomas. The false negative rate for thyroid carcinomas in group II was caused by regression areas in the center of the tumors (3 cases) as well as one microcarcinoma. Preoperative fine-needle aspiration cytology of the thyroid gland reduces the number of patients operated on for multinodular goitre or cold nodules especially in cases suspicious of carcinoma.

Intercellular communication, tumor promotion and non-genotoxic carcinogenesis: relationships based upon structural considerations.

An SAR model for inhibition of metabolic cooperation (iMC) was developed. The structural and physicochemical features associated with the ability to cause iMC are primarily lipophilic moieties consistent with the possibility that they represent receptor-binding ligands. There are also significant parallels between the structural descriptors associated with iMC and those associated with tumor promotion and with carcinogenesis in rodents. Overall, the present study provides structural evidence that iMC is a feature associated with the carcinogenic process.

[Primary angiosarcoma of the breast]. / Primäres Angiosarkom der Mamma.

We report on a 39 year old woman with a biopsy diagnosed angiosarcoma of the breast. Surgical treatment consisted of a modified radical mastectomy with axillary lymph node dissection (level I and II). The size of the tumor was 4.5 x 3.5 x 2.3 cm with G II grading. In addition the patient was put on postoperative chemotherapy (EC). Soft tissue sarcomas of the breast are very rare tumors (0.04 to < 1 % of all malignant breast tumors). The etiology of most of the vascular neoplasias of the breast is therapy associated such as preexisting surgery and radiotherapy. We found a primary angiosarcoma of the breast and tried to demonstrate aspects of the morphological diagnosis, prognosis and treatment of this disease.