Imaging Stray Magnetic Field of Individual Ferromagnetic Nanotubes.

We use a scanning nanometer-scale superconducting quantum interference device to map the stray magnetic field produced by individual ferromagnetic nanotubes (FNTs) as a function of applied magnetic field. The images are taken as each FNT is led through magnetic reversal and are compared with micromagnetic simulations, which correspond to specific magnetization configurations. In magnetic fields applied perpendicular to the FNT long axis, their magnetization appears to reverse through vortex states, that is, configurations with vortex end domains or in the case of a sufficiently short FNT with a single global vortex. Geometrical imperfections in the samples and the resulting distortion of idealized magnetization configurations influence the measured stray-field patterns.

Polarity dependent strongly inhomogeneous In-incorporation in GaN nanocolumns.

In this work, GaN/InGaN/GaN nanocolumns (NCs) have been grown by molecular beam epitaxy. Selective area growth (SAG) and self-organized growth (SOG) were performed simultaneously in patterned and unpatterned regions of the same substrate, respectively. The resulting structures show different tip morphologies and structural properties due to the different polarity along the growth direction, namely Ga-polar with r-plane faceted tips for the SAG NCs and N-polar with c-plane top facet for the SOG ones. When growing Ga-polar GaN/InGaN NCs, no indium is incorporated at a substrate temperature of [Formula: see text]°C. Rather, indium incorporation takes place under the same growth conditions on the N-polar NCs. The In-incorporation is investigated by means of nano x-ray fluorescence and diffraction, high-angle annular dark-field scanning transmission electron microscopy and high-resolution transmission electron microscopy.

[Thromboprophylaxis and platelet aggregation inhibitors in spinal surgery: perioperative management]. / Thromboseprophylaxe und Aggregationshemmer in der Wirbelsäulenchirurgie: perioperative Management.

BACKGROUND: The perioperative use of anticoagulants (AC) and platelet aggregation inhibitors (PAI) in the field of spinal surgery suggests an increased rate of epidural bleeding. However, evidence is lacking and these medications are most often indispensable in the prevention of thromboembolic complications. Comprehensive recommendations for the correct use of AC and PAI are lacking. OBJECTIVE: The aim of this study was an analysis of the current situation with regards to the use of AC and PAI in spinal surgery and development of new recommendations. MATERIAL AND METHODS: Two independent surveys on the perioperative use of AC and PAI were obtained from centers for spinal surgery in Germany. The study obtained information on the perioperative use of AC and PAI, risk assessment of thromboembolic and hemorrhagic events as well as on the type and extent of the substance groups used. RESULTS: Almost the entire patient collective (98%) received perioperative low molecular weight heparin. In 64% the medical prophylaxis was started before surgery and in 36% after surgery. The period of prophylaxis was determined arbitrarily. Approximately 40% of interviewees employed paravertebral infiltration and 19% injected into the epidural space in patients on PAI medication. Open spinal canal surgery was performed in 30% of PAI medicated patients and closed spinal canal surgery was executed in 40%. The risk assessment of PAI differed significantly between aspirin and receptor blocker medication as well as dual administration of PAI. DISCUSSION: The use of AC and PAI in spinal surgery in Germany is very heterogeneous and large deviations from the guidelines frequently occurred. Therefore, there is a strong need for further studies to accurately assess the perioperative use of AC and PAI and to formulate precise recommendations.

Five-year Evaluation of Chronic Diseases in Hamadan, Iran: 2005-2009.

BACKGROUND: Now the increasing growth of chronic diseases is the major health challenge worldwide. This survey was conducted to assess noncommunicable diseases related risk factors. METHODS: A population-based cross sectional study was conducted in 2005 and repeated annually by 2009 in Hamadan province, the west of Iran using two-stage cluster sampling method. A total sample of 6500 subjects 15 to 64 years old were enrolled. RESULTS: The total prevalence of cigarette smoking was 18% [95% CI 17% to 19%], 35.1% in men versus 1.1% in women. The smokers consumed on average 15 cigarettes per day. Almost 26.3% [95% CI 24.8% to 27.7%] of the target population eat five or more servings of fruits and vegetables per day; 52.8% [95% CI 51.2% to 54.3%] had work related physical activity; 28.1% [95% CI 26.7% to 29.4%] had physical activity during leisure time; 80.3% [95% CI 79.0% to 81.5%] had transportation related physical activity; 47.2% [95% CI 46.0% to 48.4%] were either overweight or obese; 8.1% [95% CI 7.1% to 9.2%] had impaired fasting blood sugar or were confirmed diabetes; 33.7% [95% CI 31.9% to 35.5%] had hypercholesterolemia; and 15.6% [95% CI 13.0% to 18.3%] had hypertriglyceridemia. There was a statistically significant association of age and gender with body mass index, systolic and diastolic hypertension, hyperglycemia, hypercholesterolemia and hypertriglyceridemia. CONCLUSIONS: The evidences of the present survey promise a silent progressive epidemic of chronic diseases among Iranian citizens that may lead to an increasing growth of noncommunicable diseases in the next decade.

Breast cancer metastasis to the medulla oblongata: a case report.

Breast cancer metastasis to the brain stem is uncommon. Because of the rarity of the condition, the clinical course of such patients is not known. The case of a 41-year-old woman with advanced-stage carcinoma of the breast involving the medulla oblongata is presented and the literature concerning management, including patient outcome, is reviewed.

Contribution of PET imaging to the initial staging and prognosis of patients with Hodgkin's disease.

BACKGROUND: Positron emission tomographic (PET) scanning utilizing [18F]fluorodeoxyglucose (FDG) is a new method of tumor imaging based on the increased glucose metabolic activity of malignant tumors. In Hodgkin's disease (HD), PET has proven value for the evaluation of residual masses following treatment and for the early diagnosis of relapse. In the initial staging of HD, PET frequently shows a higher stage than conventional methods (upstaging by PET). In the present study, we evaluated the frequency of stage changes by PET in a multicenter setting and determined its prognostic relevance. PATIENTS AND METHODS: A total of 73 patients with newly diagnosed HD were staged with both conventional methods and whole-body PET scanning. All histological types and stages were represented. The median time of follow-up after the initial diagnosis was 25 months (range 1 month to 5 years). The response to treatment was determined by standard clinical and diagnostic criteria. For the purpose of this analysis, data from a PET center associated with a university medical center and a PET center associated with a group oncology practice were combined. RESULTS: A total of 21 patients (28.8%) were upstaged by PET compared with conventional methods. In two cases (2.7%), a lower stage was suggested by PET scanning. With one possible exception, the upstaging had no obvious clinical or biological correlate. Among 12 patients in stage I (A + B) by conventional methods, seven were upstaged by PET (58.3%), four to stage II, one to stage III and two to stage IV. Among 42 patients in stage II, eight were upstaged by PET (19.0%), six to stage III and two to stage IV. Among 12 patients in stage III, six (50%) were upstaged to stage IV by PET. If only early-stage patients and major changes are considered (stages IA-IIB to III or IV), among 49, 10 were upstaged to III or IV, whereas in 39 staging was unchanged following PET. In the former group, three relapsed or were refractory compared with none in the latter group (P<0.006). In advanced stage patients (IIIA or IIIB) a trend toward treatment failure was apparent in patients who were upstaged by PET. CONCLUSIONS: PET scanning is an interesting new modality for the accurate staging of patients with HD and frequently shows a higher stage than conventional methods. PET should be performed at initial diagnosis and should be included in prospective studies of patients with HD. Upstaging by PET may represent a risk factor for a more advanced stage or a biologically more aggressive tumor. Patients with early-stage disease as identified by conventional methods have a significant risk of treatment failure if a more advanced stage is indicated by PET. At present, major stage changes suggested by PET imaging should be confirmed by an independent diagnostic method.

Systemic naloxone enhances cerebral blood flow in anesthetized morphine-dependent rats.

Laser-Doppler flowmetry was used to study cerebral cortical blood flow responses to morphine and naloxone in morphine-naive and -dependent rats. The experiments were performed in spontaneously breathing anesthetized rats. Morphine (10 mg/kg, i.p.) administration reduced regional cerebral blood flow in control, sham-operated and morphine-dependent rats, but the depressant effect of morphine in morphine-dependent animals was less than that in control and sham-operated groups. While naloxone (0.5 mg/kg, s.c.) had no considerable effect on regional cerebral blood flow in control and sham-operated groups, it increased regional blood flow in morphine dependent ones. The depressant effect of morphine in all groups and the enhancing effect of naloxone in morphine-dependent animals were not seen after local application of lidocaine at the recording site. This study may provide a framework to study the cellular and molecular mechanisms responsible for coupling neuronal electrical activity with regional alterations in blood flow during precipitation of morphine withdrawal.

Analysis of relative mRNA levels and protein patterns in brains of rat strains bred for differing levels of emotionality.

mRNA and protein populations were studied in the brains of Maudsley reactive (MR) and Maudsley nonreactive (MNR) rat strains, which exhibit differing levels of emotionality. Translational analysis of forebrain mRNA indicated that the relative levels of two translation products (42 kDA, pI 5.0; 30 kDa, pI 5.8) were increased in the MR compared to the MNR strain. In addition, a charge-shift variant of a 36 kDa protein was present in the MR strain. Analysis of brain protein patterns indicated that a protein of 39 kDa, pI 5.0, was found to be more abundant in MR compared with MNR strains in both frontal cortex and hippocampus and the relative level of one protein (40 kDa, pI 5.8) was decreased in the frontal cortex.

Characterisation and regional localisation of pre- and postsynaptic glycoproteins of the chick forebrain showing changed fucose incorporation following passive avoidance training.

To identify those glycoproteins whose synthesis or modification is necessary for memory formation, we have studied the uptake of radiolabelled fucose into synaptic plasma membranes (SPMs) and postsynaptic densities (PSDs) derived from two specific left and right forebrain loci, at two different times after training of 1-day-old chicks on a one-trial passive avoidance learning task. To increase the reliability of the comparison, a double-labelling method was used. Tissue samples from intermediate medial hyperstriatum ventrale (IMHV) and lobus parolfactorius (LPO) were isolated at 6 and 24 h after training. At both times, training resulted in region-specific changes, both increases and decreases, in incorporated radioactivity into pre- and postsynaptic glycoproteins. After 6 h, there was a relative decline in incorporation into both SPMs and PSDs of the right IMHV of trained chicks, a decline that persisted in the PSDs until 24 h. A small decline in incorporation in SPMs from the right LPO of trained chicks at 6 h was reversed by 24 h, by which time there was a 64% increase in incorporation into SPMs and a 24% increase into PSDs of the left LPO. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis of left and right hemisphere samples containing LPO revealed that 6 h after training the main effect was presynaptic, including a reduction of incorporation into high molecular mass glycoproteins, of 150-180 kDa, and an increase in a lower molecular mass (41 kDa) fraction. By 24 h after training, a left hemisphere presynaptic glycoprotein of molecular mass approximately 50 kDa showed the biggest increase in fucosylation. In addition, a wide group of postsynaptic glycoproteins of both hemispheres, in the ranges 150-180, 100-120, and 33 kDa now showed increases in incorporation. Some other fractions showed decreases. These results are in accord with previous data on incorporation obtained using the amnesic agent 2-deoxygalactose. They also support the hypothesis that memory formation involves the strengthening of connections between pre- and postsynaptic neurons of the LPO by growth or modulation of pre- and postsynaptic structures.

An investigation of experimental conditions for studying protein phosphorylation in micro-slices of rat brain by two-dimensional electrophoresis.

Procedures are described for studying protein phosphorylation in 1 mm diameter micro-slices of rat brain tissue using two-dimensional electrophoresis as analytical tool. The activity of several protein phosphorylating systems, including a major system phosphorylating a 40 kDa substrate complex, was highly dependent on the procedures used for micro-slice preparation and on the Ca2+-content of the preparation medium. Under optimal conditions the pattern of phosphorylation observed in micro-slices closely resembled that obtained by in vivo labelling.

Studies on the metal-complex of acetyl salicylic acid (aspirin).

The present communication deals with the isolation of acetyl salicylic acid (aspirin complexes with Bi+3 Zn+2 and UO2+2. The characterization of 1:2 complexes have been carried out with the help of conductometric, pH met;ric, elemental analysis and IR spectral studies. Spectrophotometric studies in case of UO2+2 (the only colored complex) in range of 4.2 to 5.5 pH show absorption at 490 nm and complex obey Beers Law at the concentration range of 0.01 M to 0.1 M.