Antinociceptive pharmacology of N-[[4-(4,5-dihydro-1H-imidazol-2-yl)phenyl]methyl]-2-[2-[[(4-methoxy-2,6-dimethylphenyl) sulfonyl]methylamino]ethoxy]-N-methylacetamide, fumarate (LF22-0542), a novel nonpeptidic bradykinin B1 receptor antagonist

The antinociceptive pharmacology of N-[[4-(4,5-dihydro-1H-imidazol-2-yl)phenyl]methyl]-2-[2-[[(4-methoxy-2,6-dimethylphenyl) sulfonyl]methylamino]ethoxy]-N-methylacetamide fumarate (LF22-0542), a novel nonpeptidic B1 antagonist, was characterized. LF22-0542 showed high affinity for human and mouse B1 receptors with virtually no affinity for the human B2 receptor; a selectivity index of at least 4000 times was obtained when LF22-0542 was profiled throughout binding or cell biology assays on 64 other G-protein-coupled receptor, 10 ion channels, and seven enzymes. LF22-0542 was a competitive B1 receptor antagonist and elicited significant antinociceptive actions in the mouse acetic acid-induced writhing assay, as well as in the second phases of formalin-induced nociception in mice and in both the first and second phases of the formalin response in rats. LF22-0542 was active after s.c. but not p.o. administration. In B1 receptor knockout (KO) mice, acetic acid and formalin responses were significantly reduced and LF22-0542 had no additional effects in these animals. LF22-0542 alleviated thermal hypersensitivity in both acute (carrageenan) and persistent inflammatory (complete Freund's adjuvant) pain models in rats. LF22-0542 produced a full reversal of experimental neuropathic thermal hypersensitivity but was inactive in reversing nerve injury-induced tactile hypersensitivity in rats. In agreement with this observation, B1 KO mice subjected to peripheral nerve injury did not show thermal hypersensitivity but developed nerve injury-induced tactile hypersensitivity normally. The data demonstrate the antihyperalgesic actions of a selective systemically administered B1 receptor antagonist and suggest the utility of this class of agents for the treatment of inflammatory pain states and for some aspects of neuropathic pain.

Evaluation of preoperative high magnetic field motor functional MRI (3 Tesla) in glioma patients by navigated electrocortical stimulation and postoperative outcome

OBJECTIVES

The validity of 3 Tesla motor functional magnetic resonance imaging (fMRI) in patients with gliomas involving the primary motor cortex was investigated by intraoperative navigated motor cortex stimulation (MCS).

METHODS

Twenty two patients (10 males, 12 females, mean age 39 years, range 10-65 years) underwent preoperative fMRI studies, performing motor tasks including hand, foot, and mouth movements. A recently developed high field clinical fMRI technique was used to generate pre-surgical maps of functional high risk areas defining a motor focus. Motor foci were tested for validity by intraoperative motor cortex stimulation (MCS) employing image fusion and neuronavigation. Clinical outcome was assessed using the Modified Rankin Scale.

RESULTS

FMRI motor foci were successfully detected in all patients preoperatively. In 17 of 22 patients (77.3%), a successful stimulation of the primary motor cortex was possible. All 17 correlated patients showed 100% agreement on MCS and fMRI motor focus within 10 mm. Technical problems during stimulation occurred in three patients (13.6%), no motor response was elicited in two (9.1%), and MCS induced seizures occurred in three (13.6%). Combined fMRI and MCS mapping results allowed large resections in 20 patients (91%) (gross total in nine (41%), subtotal in 11 (50%)) and biopsy in two patients (9%). Pathology revealed seven low grade and 15 high grade gliomas. Mild to moderate transient neurological deterioration occurred in six patients, and a severe hemiparesis in one. All patients recovered within 3 months (31.8% transient, 0% permanent morbidity).

CONCLUSIONS

The validation of clinically optimised high magnetic field motor fMRI confirms high reliability as a preoperative and intraoperative adjunct in glioma patients selected for surgery within or adjacent to the motor cortex.

Effects of education, self-care instruction and physical exercise on patients with chronic heart failure

BACKGROUND

Evidence is now evolving of the importance of team management for patients with chronic heart failure. This includes education, patient self-care and physical exercise training. How such programs should be implemented is still under discussion.

AIM

To assess the efficacy of an in-hospital rehabilitation clinic-based program, we studied its influence on cardiopulmonary parameters and quality of life in an outpatient setting.

METHODS AND RESULTS

75 patients (62 male, 13 female, mean age 65+/-8 years) underwent an exercise program including education, bicycle ergometer, muscle strength training and the 6-min walk test as a training unit for 4 weeks. Patients were studied at baseline (T1), before discharge (T2) and after a follow-up period of 29.9+/-5.5 weeks (T3). Baseline data (T1): left ventricular ejection fraction (LVEF): 33.8+/-7.6%, left ventricular end-diastolic volume (LVEDV): 130+/-51 ml, peak VO(2): 12.3+/-4.3 ml/kg, maximum work load (Watt max): 71+/-27 W. At discharge (T2) and follow-up (T3) LVEF increased to 36.8+/-8% and 41.8+/-9.2%, LVEDV decreased to 127+/-43 ml and 114+/-40 ml, peak VO(2) increased to 14.1+/-5.1 ml/kg and 15.2+/-5 ml/kg, and Watt max increased to 84+/-28 Wand 98+/-42 W (all p<0.01). Quality of life improved significantly at discharge and follow-up in nearly all domains and in the summary score for physical health. There were no significant changes for anxiety and depression at T2 and T3.

CONCLUSION

A specialized in hospital rehabilitation program including education, patient self management and training has a sustained positive effect on cardiopulmonary parameters and physical well-being.

Achievement of insulin independence via pancreatic islet transplantation using a remote isolation center: a first-year review

BACKGROUND

Owing to advances in both immunosuppressive protocols and pancreatic islet isolation techniques, insulin independence has recently been achieved in type 1 insulin-dependent diabetics (IDDM) via pancreatic islet transplantation (PIT). Although the dissemination of immunosuppressive protocols is relatively easy, transferring the knowledge and expertise required to isolate a large number of quality human islets for transplantation is a far greater challenge. Therefore, in an attempt to centralize the critical islet processing needed for islet transplantation and to avoid the development of another islet processing center, we have established a collaborative islet transplant program between two geographically distant transplant centers.

PATIENTS AND METHODS

Eleven consecutive type 1 IDDM patients with a history of severe hypoglycemia and metabolic instability underwent PIT at the Methodist Hospital (TMH) in Houston, Texas, utilizing pancreatic islets isolated at the Diabetes Research Institute (DRI) at the University of Miami in Miami, Florida between January 1, 2002 and June 31, 2003. Forty-one pancreata have been procured in the Houston area and have subsequently been transported for isolation at the DRI following enzymatic ductal perfusion by the automated method (Ricordi chamber). Following purification the islets were immediately transported back to TMH in Houston and transplanted via percutaneous transhepatic portal infusion. Immunosuppression regimen consisted of sirolimus, tacrolimus, and daclizumab.

RESULTS

Following harvesting, donor pancreata arrived at the DRI for initiation of the isolation process within 6.5 hours of cross-clamping (median time 5.4 hours; range 4.8 to 6.5 hours). The islets were immediately transported back to TMH for final sterility and viability tests and transplanted via percutaneous transhepatic portal vein infusion. The harvesting of 41 pancreata has yielded a number of pancreatic islets sufficient for transplantation (>5000 IEQ/kg recipient body weight) 26 times (63% of harvested pancreata). Thus far, three patients have received three PITs and eight patients have received two PITs. Six remain insulin independent. All have experienced a decrease in serum hemoglobin A(1c) levels, and both basal and stimulated C-peptide levels have increased. There have been no major complications related to the procedure or the immunosuppressive regimen used.

CONCLUSIONS

Our series demonstrates that pancreatic islets isolated at a remote isolation center can successfully and safely be used for PIT and the achievement of insulin independence.

[Use of contrast agent in high-field MRI (3 T)]

The basic diagnostic efficacy of MR contrast medium in the evaluation of primary brain tumors and its clinical usefulness in the detection of brain metastases with single and cumulative triple-dose was compared using a high-field 3 T MR unit and a 1.5 T MR unit. Additionally, the effect of contrast agent on high-resolution MR venography based on the BOLD effect was evaluated at both field strengths. Tumor-brain contrast after gadodiamide administration, as assessed by means of statistical evaluation of MP-RAGE scans and T1-SE images, was significantly higher at 3 T than at 1.5 T. The subjective assessment of cumulative triple-dose 3 T images obtained the best results in the detection of brain metastases, followed by 1.5 T cumulative triple-dose enhanced images. Due to higher spatial resolution, contrast-enhanced MR venography at 3 T showed more details in and around tumors than at 1.5 T, additionally enhanced by stronger susceptibility weighting and higher signal-to-noise ratio at 3 T. In summary, administration of gadolinium-based contrast agent produces higher contrast between tumor and normal brain at 3 T than at 1.5 T, helps to detect more cerebral metastases at 3 T than at 1.5 T in single and cumulative triple dose, and improves MR venography at 3 T with increase in spatial resolution within the same measurement time, thus providing more detailed information.

Distribution of reflection coefficients in absorbing chaotic microwave cavities

The distribution of reflection coefficients P(R) for chaotic microwave cavities with time-reversal symmetry is investigated in different absorption and antenna coupling regimes. For all regimes the agreement between experimental distributions and random-matrix theory predictions is very good, provided both the antenna coupling T(a) and the wall absorption strength T(w) are taken into account in an appropriate way. These parameters are determined by independent experimental quantities.

[Eating disorders in children and adolescents]

Eating disorders in early childhood increase the risk of anorexia or bulimia nervosa in adolescents. In the case of babies feeding disorders and pica are differentiated. Eating disorders in pre-school and primary school age are common. A main cause is neophobia, which can be treated by the observance of certain rules at meal-times (taken together with the family). Anorexia and bulimia affect mainly adolescents. Anorexia is associated with a number of mental and somatic comorbidities that need to be considered for the diagnosis and treatment.

Transition from Gaussian-orthogonal to Gaussian-unitary ensemble in a microwave billiard with threefold symmetry

Recently it has been shown that time-reversal invariant systems with discrete symmetries may display, in certain irreducible subspaces, spectral statistics corresponding to the Gaussian-unitary ensemble (GUE) rather than to the expected orthogonal one (GOE). A Kramers-type degeneracy is predicted in such situations. We present results for a microwave billiard with a threefold rotational symmetry and with the option to display or break a reflection symmetry. This allows us to observe the change from GOE to GUE statistics for one subset of levels. Since it was not possible to separate the three subspectra reliably, the number variances for the superimposed spectra were studied. The experimental results are compared with a theoretical and numerical study considering the effects of level splitting and level loss.

Effective Hamiltonian for a microwave billiard with attached waveguide

In a recent work the resonance widths in a microwave billiard with attached waveguide were studied in dependence on the coupling strength [E. Persson et al., Phys. Rev. Lett. 85, 2478 (2000)], and resonance trapping was experimentally found. In the present paper an effective Hamiltonian is derived that depends exclusively on billiard and waveguide geometry. Its eigenvalues give the poles of the scattering matrix provided that the system and environment are defined adequately. Further, we present the results of resonance trapping measurements where, in addition to our previous work, the position of the slit aperture within the waveguide was varied. Numerical simulations with the derived Hamiltonian qualitatively reproduce the experimental data.

Characterization of BOLD activation in multi-echo fMRI data using fuzzy cluster analysis and a comparison with quantitative modeling

A combination of multiple gradient-echo imaging and exploratory data analysis (EDA), i.e. fuzzy cluster analysis (FCA), is proposed for separation and characterization of BOLD activation in single-shot spiral functional magnetic resonance imaging (fMRI) experiments at 3 T. Differentiation of functional activation using FCA is performed by clustering pixel signal changes (DeltaS) as a function of echo time (TE). Further vascular classification is supported by the localization of activation and the comparison with a single-exponential decay model. In some subjects, an additional indication for large vessels within a voxel was found as oscillation of the fMRI signal difference vs echo time (TE). Such large vessels may be separated from small vessel activation and, therefore, our proposed procedure might prove useful if a more specific functional localization is desired in fMRI. In addition to the signal change DeltaS, DeltaT(2)*/T(2)* is significantly different between activated regions. Averaged over all eight subjects DeltaT(2)* is 1.7 +/- 0.2 ms in ROIs with the highest signal change characterized as containing large vessels, whereas in ROIs corresponding to microvascular environment average DeltaT(2)* values are 0.8 +/- 0.1 ms.

Expression of growth differentiation factor-15/ macrophage inhibitory cytokine-1 (GDF-15/MIC-1) in the perinatal, adult, and injured rat brain

We and others have recently cloned a new member of the transforming growth factor-beta superfamily, growth differentiation factor-15/ macrophage inhibitory cytokine-1 (GDF-15/MIC-1). Using in situ hybridization and immunohistochemistry, we determined the distribution of GDF-15/MIC-1 mRNA and protein in the perinatal and cryolesioned adult rat brain. The choroid plexus epithelium of all ventricles represents the site of strongest and almost exclusive mRNA expression in the normal perinatal and adult brain. The newborn rat brain reveals GDF-15/MIC-1 immunoreactivity (ir) in ependymal cells lining the ventricles, in the striatal subventricular zone, and in populations of nonneural cells of the thalamic/hippocampal lamina affixa, in addition to that in the choroid plexus. Unilateral cryogenic cortical lesioning induced a significant increase of GDF-15/MIC-1 mRNA expression and ir at the lesion site and expression in presumed neurons within the dorsal thalamic area. At the lesion site, GDF-15/MIC-1-producing cells showed immuncytochemical features of neurons, macrophages, and activated microglial cells. Fluorescent microscopy revealed both intra- and extracellular GDF-15/MIC-1 ir. Up-regulation of GDF-15/MIC-1 in activated macrophages (Mstraight phi) is also supported by RT-PCR, ICC, and Western blot experiments showing pronounced induction of GDF-15/MIC-1 expression (mRNA and protein) in retinoic acid/phorbol ester-stimulated human M phi. Our data suggest that 1) GDF-15/MIC-1 is secreted into the cerebrospinal fluid and 2) in the newborn brain may penetrate through the ependymal lining and act on developing neurons and/or glial cells. As a constituent of cells in the lamina affixa, the protein might be involved in the regulation of mesenchyme-epithelial interactions. Finally, GDF-15/MIC-1 may also act within the antiinflammatory cytokine network activated in CNS lesions.

Spatially resolved single bead analysis: homogeneity, diffusion, and adsorption in cross-linked polystyrene

Spatially resolved single bead analysis in the micrometer range was employed as a tool for evaluating homogeneity, diffusion, and adsorption in solid-phase supported reactions. Fluorescence microscopy (confocal and non-confocal) as well as IR microscopy were used to detect both the distribution of products and the formation of product gradients in representative reactions. For the first time, the optical slices of whole beads obtained by confocal fluorescence microscopy were compared with the fluorescence images of microtome-sliced beads. The experiments revealed that only physical slices of polystyrene beads deliver realistic representations of the distribution of fluorophores, and confirmed-in contrast to a recent report-the homogeneity of functional site distribution in polystyrene beads. Moreover, the pattern of product formation obtained from an acylation reaction as well as from an alkylation reaction were employed as probes to study the impact of bead size, diffusion, and adsorption on the reaction progress. A simulation of the diffusion process was conducted and compared with the experimental results. Diffusional control was found neither in the case of the alkylation nor in the case of the acylation reaction under investigation. As a consequence, the reaction progress was not a function of the bead sizes as proposed in the literature. Interestingly, in the case of rhodamine acylation with substoichiometric amounts an adsorption-controlled reaction was found. This result highlights the significance of adsorptive effects in solid-phase supported chemistry.

Time course of apoptotic cell death after experimental neurotrauma

Traumatic or ischemic brain injury may give rise to the development of secondary brain damage. In the present study the time course of TUNEL staining which is widely used to delineate apoptotic reaction pattern was followed after experimental neurotrauma in order to test the hypothesis that apoptotic cell death may be involved in the development of secondary brain damage. Neurotrauma was induced in male Wistar rats by applying a cold probe to the exposed dura over the temporo-parietal cortex. Animals were sacrificed between 1 and 72 hours after trauma and coronal sections prepared from the lesioned area and adjacent tissue. The TUNEL staining was employed to detect DNA-fragmentation and conventional HE staining of sequential slices to delineate the extent of the lesion. Occurrence of positively stained cells was detected by a computer-based quantification system and stored on hard disk. TUNEL-positive nuclei were observed as early as one hour after lesion and peaked at 3 hours. There after, the number of cells detected decreased steadily. Histological examination revealed two different types of morphology in TUNEL-positive cells. A small proportion termed type I-cells displayed additional signs of apoptotic cell death such as nuclear condensation and fragmentation while type-II were considered to undergo necrotic cell death. Thus, TUNEL staining proved to be an unspecific marker of apoptotic cell death in the present study. Nevertheless, the data suggest that apoptotic cell death does not contribute substantially to the final extent of cold induced brain tissue damage.

Experimental investigation of a regime of Wigner ergodicity in microwave rough billiards

We study experimentally a new regime of Wigner ergodicity [K.M. Frahm and D.L. Shepelyansky, Phys. Rev. Lett. 79, 1833 (1997)] in a microwave rough billiard. We show that in the Wigner regime, eigenstates are extended over the whole energy surface but have a strongly peaked nonergodic structure. The Shannon width of the eigenstate distributions is calculated to estimate their spreads and to find their departure from the ergodic distributions.

Dentin barrier test with transfected bovine pulp-derived cells

Growth kinetics of SV40 large T-antigen-transfected bovine pulp-derived cells on dentin were investigated. These cells were used in a dentin barrier test device, and the system was evaluated by testing a set of dental filling materials. Cells (120 cells/mm2) were seeded on dentin slices and incubated for up to 21 days. Cell proliferation was recorded using MTT assay. For cytotoxicity tests 3500 cells/mm2 were seeded on dentin discs, which were then incorporated into the dentin barrier test device. After 72 h preincubation test materials were applied. After a 24 h exposure with or without perfusion of the pulpal part of the test device, cell survival was evaluated using MTT assay. The cells revealed similar growth kinetics on dentin slices and on tissue culture plates. In cytotoxicity tests the cells were more sensitive toward the test materials than previously used three-dimensional cultures of human foreskin fibroblasts and as anticipated from clinical experience. Further improvement is expected by using three-dimensional cultures of pulp-derived cells.

High-resolution MR venography at 3.0 Tesla

PURPOSE

The aim of this study was to investigate the visualization of small venous vessels in the normal human brain at a field strength of 3 Tesla.

METHODS

T2*-weighted, three-dimensional gradient-echo images were acquired by exploiting the magnetic susceptibility difference between oxygenated and deoxygenated hemoglobin in the vasculature and microvasculature. The spatial resolution was 0.5 x 0.5 x 1 mm3, and sequence parameters were varied to obtain good vessel delineation. Improved visibility of venous vessels was obtained by creating phase mask images from the magnetic resonance phase images and multiplying these by the magnitude images. Venograms were created by performing a minimum intensity projection over targeted volumes.

RESULTS

Highly detailed visualization of venous structures deep in the brain and in the superficial cortical areas were obtained without administration of an exogenous contrast agent; compared with similar studies performed at 1.5 T, the echo time could be reduced from typically 40-50 ms to 17-28 ms.

CONCLUSION

Imaging at high-field strength offers the possibility of improved resolution and the delineation of smaller vessels compared with lower field strengths.

Interaction of temperature, humidity, driver preferences, and refrigerant type on air conditioning compressor usage

Recent studies have shown large increases in vehicle emissions when the air conditioner (AC) compressor is engaged. Factors that affect the compressor-on percentage can have a significant impact on vehicle emissions and can also lead to prediction errors in current emissions models if not accounted for properly. During 1996 and 1997, the University of California, Riverside, College of Engineering-Center for Environmental Research and Technology (CE-CERT) conducted a vehicle activity study for the California Air Resources Board (CARB) in the Sacramento, CA, region. The vehicles were randomly selected from all registered vehicles in the region. As part of this study, ten vehicles were instrumented to collect AC compressor on/off data on a second-by-second basis in the summer of 1997. Temperature and humidity data were obtained and averaged on an hourly basis. The ten drivers were asked to complete a short survey about AC operational preferences. This paper examines the effects of temperature, humidity, refrigerant type, and driver preferences on air conditioning compressor activity. Overall, AC was in use in 69.1% of the trips monitored. The compressor was on an average of 64% of the time during the trips. The personal preference settings had a significant effect on the AC compressor-on percentage but did not interact with temperature. The refrigerant types, however, exhibited a differential response across temperature, which may necessitate separate modeling of the R12 refrigerant-equipped vehicles from the R134A-equipped vehicles. It should be noted that some older vehicles do get retrofitted with new compressors that use R134A; however, none of the vehicles in this study had been retrofitted.

Observation of resonance trapping in an open microwave cavity

The coupling of a quantum mechanical system to open decay channels has been theoretically studied in numerous works, mainly in the context of nuclear physics but also in atomic, molecular, and mesoscopic physics. Theory predicts that with increasing coupling strength to the channels the resonance widths of all states should first increase but finally decrease again for most of the states. In this Letter, the first direct experimental verification of this effect, known as resonance trapping, is presented. In the experiment a microwave Sinai cavity with an attached waveguide with variable slit width was used.

The Syk tyrosine kinase suppresses malignant growth of human breast cancer cells

Syk is a protein tyrosine kinase that is widely expressed in haematopoietic cells. It is involved in coupling activated immunoreceptors to downstream signalling events that mediate diverse cellular responses including proliferation, differentiation and phagocytosis. Syk expression has been reported in cell lines of epithelial origin, but its function in these cells remains unknown. Here we show that Syk is commonly expressed in normal human breast tissue, benign breast lesions and low-tumorigenic breast cancer cell lines. Syk messenger RNA and protein, however, are low or undetectable in invasive breast carcinoma tissue and cell lines. Transfection of wild-type Syk into a Syk-negative breast cancer cell line markedly inhibited its tumour growth and metastasis formation in athymic mice. Conversely, overexpression of a kinase-deficient Syk in a Syk-positive breast cancer cell line significantly increased its tumour incidence and growth. Suppression of tumour growth by the reintroduction of Syk appeared to be the result of aberrant mitosis and cytokinesis. We propose that Syk is a potent modulator of epithelial cell growth and a potential tumour suppressor in human breast carcinomas.

sigma factor selectivity of Escherichia coli RNA polymerase: role for CRP, IHF and lrp transcription factors

osmY is a stationary phase-induced and osmotically regulated gene in Escherichia coli that requires the stationary phase RNA polymerase (Esigma(S)) for in vivo expression. We show here that the major RNA polymerase, Esigma(70), also transcribes osmY in vitro and, depending on genetic background, even in vivo. The cAMP receptor protein (CRP) bound to cAMP, the leucine-responsive regulatory protein (Lrp) and the integration host factor (IHF) inhibit transcription initiation at the osmY promoter. The binding site for CRP is centred at -12.5 from the transcription start site, whereas Lrp covers the whole promoter region. The site for IHF maps in the -90 region. By mobility shift assay, permanganate reactivity and in vitro transcription experiments, we show that repression is much stronger with Esigma(70) than with Esigma(S) holoenzyme. We conclude that CRP, Lrp and IHF inhibit open complex formation more efficiently with Esigma(70) than with Esigma(S). This different ability of the two holoenzymes to interact productively with promoters once assembled in complex nucleoprotein structures may be a crucial factor in generating sigma(S) selectivity in vivo.