Demonstration of angle-dependent Casimir force between corrugations

The normal Casimir force between a sinusoidally corrugated gold coated plate and a sphere was measured at various angles between the corrugations using an atomic force microscope. A strong dependence on the orientation angle of the corrugation is found. The measured forces were found to deviate from the proximity force approximation and are in agreement with the theory based on the gradient expansion including correlation effects of geometry and material properties. We analyze the role of temperature. The obtained results open new opportunities for control of the Casimir effect in micromechanical systems.

Geographical parthenogenesis and population genetic structure in the alpine species Ranunculus kuepferi (Ranunculaceae)

Geographical parthenogenesis describes the enigmatic phenomenon that asexual organisms have larger distribution areas than their sexual relatives, especially in previously glaciated areas. Classical models suggest temporary advantages to asexuality in colonization scenarios because of uniparental reproduction and clonality. We analyzed population genetic structure and self-fertility of the plant species Ranunculus kuepferi on 59 populations from the whole distribution area (European Alps, Apennines and Corsica). Amplified fragment length polymorphisms (AFLPs) and five microsatellite loci revealed individual genotypes for all populations and mostly insignificant differences between diploid sexuals and tetraploid apomicts in all measures of genetic diversity. Low frequencies of private AFLP fragments/simple sequence repeat alleles, and character incompatibility analyses suggest that facultative recombination explains best the unexpectedly high genotypic diversity of apomicts. STRUCTURE analyses using AFLPs revealed a higher number of partitions and a stronger geographical subdivision for diploids than for tetraploids, which contradicts expectations of standard gene flow models, but indicates a reduction of genetic structure in asexuals. Apomictic populations exhibited high admixture near the sexual area, but appeared rather uniform in remote areas. Bagging experiments and analyses of pollen tube growth confirmed self-fertility for pollen-dependent apomicts, but self-sterility for diploid sexuals. Facultative apomixis combines advantages of both modes of reproduction: uniparental reproduction allows for rapid colonization of remote areas, whereas facultative sexuality and polyploidy maintains genetic diversity within apomictic populations. The density dependence of outcrossing limits range expansions of sexual populations.

PT-symmetric quantum electrodynamics and unitarity

More than 15 years ago, a new approach to quantum mechanics was suggested, in which Hermiticity of the Hamiltonian was to be replaced by invariance under a discrete symmetry, the product of parity and time-reversal symmetry, PT. It was shown that, if PT is unbroken, energies were, in fact, positive, and unitarity was satisfied. Since quantum mechanics is quantum field theory in one dimension--time--it was natural to extend this idea to higher-dimensional field theory, and in fact an apparently viable version of PT-invariant quantum electrodynamics (QED) was proposed. However, it has proved difficult to establish that the unitarity of the scattering matrix, for example, the Källén spectral representation for the photon propagator, can be maintained in this theory. This has led to questions of whether, in fact, even quantum mechanical systems are consistent with probability conservation when Green's functions are examined, since the latter have to possess physical requirements of analyticity. The status of PT QED will be reviewed in this paper, as well as the general issue of unitarity.

Abstract P1-07-06: Effect of biospecimen variables on proteomic biomarker assessment in breast cancer

Background: PI3K/Akt/mTOR signaling is being actively pursued as a therapeutic target. We sought to determine how tumor heterogeneity and biospecimen variables affect assessment of PI3K/Akt/mTOR pathway activation.

Methods: Intraoperative image-guided core-needle biopsies (CNB) of primary breast tumors were prospectively collected in 53 patients with invasive breast cancer. After surgery, specimens were collected from the center and periphery of the excised tumor. CNB, central and peripheral surgical specimens were assessed with reverse phase proteomic arrays (RPPA), H&E and immunohistochemistry (IHC).

Results: The expression of standard of care markers ER, PR, and HER2 by RPPA correlated well between biospecimen types. Overall, there was a significant correlation between the expression of 132 (86%) of 154 different markers in the center and periphery; the correlation was significantly higher for smaller tumors, and with shorter cold ischemia time. Expression of many investigational prognostic markers and druggable targets on CNB correlated with expression in the surgical specimen (average of center and periphery), while others, such as EGFR and c-MET, had a weak correlation. Of 154 RPPA markers, 132 (86%) were not statistically different between the center and periphery, and 97 (67%) were not different between the CNB and the surgical specimen. On analysis of the PI3K/AKT/mTOR pathway, pAkt S473 and PTEN had a significant correlation between central and peripheral specimens, and between CNB and surgical specimens. However, pAkt S473, pS6 S235/236 and pS6 240/244 levels were higher in CNB than the central specimens both by RPPA and by IHC. When patients were classified by RPPA PI3K pathway activation score, there was a moderate agreement between classification on the CNB and central specimens (Cohen's Kappa 0.539). However 9 of 20 tumors classified as having PI3K activation on CNB were classified as not having pathway activation on central specimens.

Conclusions: There is remarkable homogeneity in expression of biomarkers within a tumor. However, proteomic markers are differentially expressed by biospecimen type and other preanalytic variables. PI3K pathway activation is greater in CNB compared to surgical samples.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-07-06.

Correlation between body mass index and orthodontic treatment outcome

OBJECTIVE

To determine whether there is a correlation between body mass index (BMI), patient cooperation, and treatment success during multibracket (MB) appliance therapy.

MATERIALS AND METHODS

All adolescent MB patients started and finished between 2007 and 2010 were analyzed. The pretreatment BMI was calculated and negative file entries such as bad oral hygiene, missed appointments, and appliance breakage were recorded. According to the number of negative entries, cooperation was classified as good, bad, or poor. Additionally, the treatment duration and the number of appointments were recorded. For the evaluation of treatment success, the pretreatment and posttreatment PAR (peer assessment rating) scores were measured.

RESULTS

Of the 77 subjects, 61 had a normal BMI (79.2%) and 16 were considered overweight (20.8%). Whereas 51.7% of the normal-weight children had a good cooperation, only 25% of the overweight patients cooperated sufficiently. Consequently, the number of patients exhibiting bad or poor cooperation was higher in the overweight group (37.5% bad, 37.5% poor) than in the normal-weight group (30.6% bad, 17.7% poor). Patients with an increased BMI had a slightly longer treatment duration (21.4 months) and needed more appointments (19.9) than their normal-weight peers (18.9 months, 18.1 appointments). The PAR (peer assessment rating) score reduction, however, was comparable (normal BMI: 17.8 points, 64.0%; increased BMI: 15.2 points, 65.3%).

CONCLUSION

In the present study, children with increased BMI did not cooperate as well during MB therapy as their normal-weight peers, but the treatment outcome was comparable in the two groups.

Seizure outcome, functional outcome, and quality of life after hemispherectomy in adults

BACKGROUND

Functional hemispherectomy is a well-established method in childhood epilepsy surgery with only a few reports on its application in adults.

METHODS

We report on 27 patients (median age 30 years, range 19-55) with a follow-up of more than 1 year (median 124 months, range 13-234). Etiology was developmental in two (one schizencephaly, one hemimegalencephaly), acquired in 21 (two hemiatrophy, 17 porencephaly, two postencephalitic), and progressive in four (Rasmussen's encephalitis).

RESULTS

At last available follow-up, 22 patients were seizure free (81 % ILAE class 1), one had auras (4 % ILAE class 2), one had no more than three seizures per year (4 % ILAE class 3). Thirty-seven percent were without antiepileptic drugs. Seventeen patients of 20 responding patients stated improved quality of life after surgery, one patient reported deterioration, and two patients reported no difference. Additionally, a self-rated postoperative functional status and changes compared to the pre-operative status was assessed. Six patients improved in gait, ten remained unchanged, and four deteriorated. Three patients improved in speech, none deteriorated. Hand function got worse five times, and in 15 cases remained unchanged. There was no mortality, one bone flap infection, and one subdural hematoma. Hydrocephalus was seen in three cases (12 %).

CONCLUSIONS

It is possible to achieve good seizure outcome results despite long-standing epilepsy across a variety of etiologies, comparable to epilepsy surgery in pediatric patients. Adult patients do not have to expect more problems with new deficits, appear to cope quite well, and mostly profit from surgery in several quality of life domains.

Association studies of gene polymorphisms in toll-like receptors 2 and 4 in Croatian patients with acute myocardial infarction

The aim of the study was to assess the frequency of SNP896A/G in the Toll-like receptor (TLR) 4 gene and SNP1350T/C in the TLR2 gene in patients with acute myocardial infarction (AMI) and to analyse the association of these SNPs with risk factors for atherosclerosis and clinical aspects of AMI in a sample of the Croatian population. We included 240 participants in the study: 120 AMI patients and 120 sex- and age-matched healthy blood donor controls. The SNP1350T/C variant in the TLR2 gene showed a lower frequency in the AMI patient group than in the control group (P = 0.033). The frequency of SNP896A/G variants in the TLR4 gene between the patients and the controls did not differ (P = 0.286). Significantly, fewer people had SNP1350T/C in the TLR2 gene (P = 0.003) among the participants with arterial hypertension than those without it. The frequency of SNP896A/G in TLR4 was the same in hypertensive patients compared with normotensive subjects (P = 0.088). SNP1350T/C in TLR2 was less frequent in the AMI patients and in those with hypertension. Thus, SNP1350T/C in TLR2 might play a protective role against AMI and arterial hypertension. The frequency of SNP896A/G in the TLR4 gene was not associated with AMI and arterial hypertension. Other risk factors for atherosclerosis and clinical aspects of myocardial infarction were not associated with the genotype distribution of the examined genes.

Effect of temperature on the progamic phase in high-mountain plants

Progamic processes are particularly temperature-sensitive and, in lowland plants, are usually drastically reduced below 10 °C and above 30 °C. Little is known about how effectively sexual processes of mountain plants function under the large temperature fluctuations at higher altitudes. The present study examines duration and thermal thresholds for progamic processes in six common plant species (Cerastium uniflorum, Gentianella germanica, Ranunculus alpestris, R. glacialis, Saxifraga bryoides, S. caesia) from different altitudinal zones in the European Alps. Whole plants were collected from natural sites shortly before anthesis and kept in a climate chamber until further processing. Flowers with receptive stigmas were hand-pollinated with allopollen and exposed to controlled temperatures between -2 and 40 °C. Pollen performance (adhesion to the stigma, germination, tube growth, fertilisation) was quantitatively analysed, using the aniline blue fluorescence method. Pollen adhesion was possible from -2 to 40 °C. Pollen germination and tube growth occurred from around 0 to 35 °C in most species. Fertilisation was observed from 5 to 30-32 °C (0-35 °C in G. germanica). The progamic phase was shortest in G. germanica (2 h at 30 °C, 12 h at 5 °C, 24 h at 0 °C), followed by R. glacialis (first fertilisation after 2 h at 30 °C, 18 h at 5 °C). In the remaining species, first fertilisation usually occurred after 4-6 h at 30 °C and after 24-30 h at 5 °C. Thus, mountain plants show remarkably flexible pollen performance over a wide temperature range and a short progamic phase, which may be essential for successful reproduction in the stochastic high-mountain climate.

Development of an itraconazole-loaded nanostructured lipid carrier (NLC) formulation for pulmonary application

Itraconazole-loaded NLC for pulmonary application were developed. In Precirol ATO 5 and oleic acid Itraconazole had the highest solubility. The solid lipid and the oil were mixable in a ratio 9:1 possessing a melting point above body temperature. 0.4% Itraconazole was dissolved in this lipid blend. Eumulgin SLM 20 was the stabilizer with the highest affinity to the lipid blend used as particle matrix. 2.5% Eumulgin SLM 20 was sufficient to obtain NLC with a narrow particle size distribution and sufficient stability. The tonicity of the formulation was adjusted with glycerol. Sterility was obtained by autoclaving. Neither the addition of glycerol nor autoclaving had an influence on the particle size and the zeta potential of Itraconazole-loaded NLC. SEM images showed spherical particles confirming the particle size measured by light scattering techniques. An entrapment efficiency of 98.78% was achieved. Burst release of Itraconazole from the developed carrier system was found. Itraconazole-loaded NLC possessed good storage stability. Nebulizing Itraconazole-loaded NLC with a jet stream and an ultrasonic nebulizer had no influence on the particle size and the entrapment efficiency of Itraconazole in the particle matrix, being a precondition for pulmonary application.

Value of ultrasound in preoperative local staging in early breast cancer

PURPOSE

The purpose of this study was to determine the precision of breast ultrasound for the measurement of breast lesions compared to the histological measurement. A number of other dependent variables were also analyzed.

MATERIAL AND METHODS

460 patients with 445 malignant lesions were examined using breast ultrasound and the lesions were measured and compared to the histologically measured size. The data was further analyzed according to histology, tumor stage, age, grading and therapy.

RESULTS

Metric comparison showed good correlation between sonography and the pathologically measured size of breast lesions, especially in tumor stage T 1 and T 2 and within ductal invasive carcinomas. Higher tumor stages lead to imprecise measurements and the histological type of lobular invasive carcinoma also results in imprecise measurements. Age and grading do not influence measurement precision.

CONCLUSION

Breast ultrasound allows precise measurement of breast lesions especially at lower tumor stages. The higher the tumor stage, the more imprecise the measurement becomes. Multivariate analysis shows no cross impact between tumor stage and histological type with respect to the quality of measurement.

The relationship between interferon-γ gene polymorphism and acute kidney allograft rejection

Cytokine gene polymorphisms have been associated with modified gene expression and cytokine production. Gamma interferon (IFN-γ) plays an important role in the pathogenesis of kidney transplant rejection. This study evaluated the association between IFN-γ gene polymorphisms and the history of acute allograft rejection in 53 adult first-transplant recipients receiving cadaveric kidney grafts. They were followed up in a single centre until 2006, for a median time of 4 years after transplantation (1-22 years). IFN-γ gene polymorphisms +874 T/A (rs2430561) were determined by polymerase chain reaction (PCR). T/T high IFN-γ genotype was found in 12, intermediate T/A in 29 and low A/A in 12 patients. Twenty-six acute kidney rejection episodes were evidenced in 20 patients, of which none occurred in the 12 patients with low IFN-γ genotype A/A. Age, gender, number of HLA (human leukocyte antigen) mismatches, ABO blood groups, HLA, time after transplantation, creatinine clearance and immunosuppressive regimens were excluded as confounding factors associated with IFN-γ genotype distribution between rejectors and non-rejectors. IFN-γ gene polymorphisms could be an important risk factor for acute kidney transplant rejection, whereas the low A/A IFN-γ genotype could be protective against rejection.

Characterization of Hydrocarbon Plasma used for a-C:H Deposition

Optical emission analysis and mass spectroscopy was applied to study the rf-glow discharge in hydrocarbons used for the deposition of amorphous hydrogenated carbon (a-C:H).The mass spectra of the positively charged ions in the plasma are characteristic for the hydrocarbon used - e.g.benzene, hexane, or methane.In contrast, the properties of the deposited a-C:H film, such as refractive index, are independent of the precursor gas.Spatially resolved optical measurements show strong emission from C, C2, and CH in the vincinity of the negatively self-biased cathode (substrate) irrespective of the precursor used.Based on these findings we conclude that the fragmentation of the impinging energetic hydrocarbons is one of the key mechanisms for the formation of hard, strongly cross-linked a-C:H films.

Resonant Raman Scattering in GaN/Al0.15 Ga0.85N and InyGa1-yN/GaN/AlxGa1-xN Heterostructures

We report on resonant Raman scattering in Al0.15Ga0.85N/GaN single quantum wells (QWs) and AlxGa1-xN/GaN/lnyGa1-yN heterostructures. By choosing appropriate excitation conditions we could probe selectively the GaN quantum well or the Al0.15Ga0.85N barrier of Al0.15Ga0.85N/GaN single quantum wells. For the InxGa1-xN material system a linear frequency shift of the E2- and A1(LO) phonon mode to lower frequencies was found with increasing In content. The shift was determined to -0.79cm-1 per % In content for the A,(LO) phonon frequency. Resonant excitation of AlxGa1-xN/GaN/InyGa1-YN heterostructures enabled us to detect phonon signals from the InxGa1-xN layer in the heterostructure and to determine its In content.

Structural Characterization of InAs/(GaIn)Sb Superlattices for IR Optoelectronics

We report on the structural characterization of InAs/(GaIn)Sb superlattices (SL) grown by solid-source molecular-beam epitaxy. SL periodicity and overall structural quality were assessed by high-resolution X-ray diffraction and Raman spectroscopy. Spectroscopic ellipsometry was found to be sensitive to the (GaIn)Sb alloy composition.

Skeletal integrity and visceral transplantation

Despite continuous improvement in long-term survival, there is no knowledge about risk of bone health impairment and management strategies before and after intestinal transplantation. Therefore, 147 adults were retrospectively studied via chart review; 70 long-term survivors, 53 candidates and 24 recipients with longitudinal follow-up. Evaluation process included measurement of bone mineral density (BMD) and allied biochemical markers. Both long-term survivors and candidates showed low bone mass with lower (p < 0.05) z-scores at hip, femoral neck and spine. Vitamin D deficiency and secondary hyperparathyroidism were observed in both groups. Prevalence of osteoporosis was 44% among long-term survivors and 36% in candidates with age, BMD, duration of parenteral nutrition, type of immunosuppression and rejection being significant risk factors. Fragility fractures occurred at a higher (p = 0.02) rate among long-term survivors (20%) compared to candidates (6%). The longitudinal study documented acceleration (p = 0.025) of bone loss after transplantation with a decline of 13.4% (femoral neck), 12.7% (hip) and 2.1% (spine). Alendronate reduced (p < 0.05) but did not prevent bone loss. In conclusion, intestinal transplant recipients are at risk of osteoporosis secondary to bone loss before and after transplantation. Accordingly, current management includes comprehensive preventive measures with prompt therapeutic intervention utilizing intravenous bisphosphonates or subcutaneous human PTH.

Indications and candidacy for active middle ear implants

Currently, there are two active middle ear implants available commercially: the Vibrant Soundbridge system and the Carina system. A third active middle ear implant, the Esteem, is under clinical evaluation. All devices are indicated for patients with moderate-to-severe hearing loss. Because active middle ear implants are directly coupled to middle ear structures, many of the problems that patients with conventional hearing aids report, such as acoustic feedback, occlusion, and irritation of the outer ear canal, are avoided. In addition, AMEI patients perform well in background noise. However, indications for AMEIs are selective and candidates should be carefully evaluated before surgery. Before considering an AMEI, patients should be provided with conventional hearing aids. Only when benefit is insufficient and audiological selection criteria are met is further candidacy evaluation indicated. Since Colletti described coupling the Vibrant Soundbridge directly onto the round window membrane in 2006, the indications for the Vibrant Soundbridge have expanded and the VSB is implanted in patients with conductive and mixed hearing losses. Patients have often undergone middle ear surgery before. Especially mixed hearing loss cases with 30-60 dB HL sensorineural hearing impairment and 30-40 dB HL air-bone gaps may be helped by this new application.

Quality analysis of selective microparticle deposition on electrically programmable surfaces

Image processing and pattern analysis can evaluate the deposition quality of triboelectrically charged microparticles on charged surfaces. The image processing method presented in this paper aims at controlling the quality of peptide arrays generated by particle based solid phase Merrifield combinatorial peptide synthesis. Incorrectly deposited particles are detected before the amino acids therein are coupled to the growing peptide. The calibration of the image acquisition is performed in a supervised training step in which all parameters of the quality analyzing algorithm are learnt given one representative image. Then, the correct deposition pattern is determined by a linear support vector machine. Knowing the pattern, contaminated areas can be detected by comparing the pattern with the actual deposition. Taking into account the resolution of the image acquisition system and its magnification factor, the number and size of contaminating particles can be calculated out of the number of connected foreground pixels.

Differential association of MUC5AC and CLCA1 expression in small cartilaginous airways of RAO-affected and control horses

REASONS FOR PERFORMING STUDY

Airway mucus accumulation is associated with indoor irritant and allergen exposure in horses with recurrent airway obstruction (RAO). Epidermal growth factor receptor (EGFR) and a chloride channel (calcium activated, family member 1; CLCA1) are key signalling molecules involved in mucin gene expression.

OBJECTIVES

We hypothesised that exposure to irritants and aeroallergens would lead to increased expression of the mucin gene eqMUC5AC and increased stored mucosubstance in the airways of RAO-affected horses, associated with increased neutrophils and CLCA1 and EGFR mRNA levels.

METHODS

We performed quantitative RT-PCR of eqMUC5AC, CLCA1 and EGFR; volume density measurements of intraepithelial mucosubstances; and cytological differentiation of intraluminal inflammatory cells in small cartilaginous airways from cranial left and right and caudal left and right lung lobes of 5 clinically healthy and 5 RAO-affected horses that had been exposed to indoor stable environment for 5 days before euthanasia.

RESULTS

Neutrophils were increased in RAO-affected horses compared to clinically healthy controls. EqMUC5AC mRNA levels were positively correlated with both CLCA1 and EGFR mRNA levels in RAO-affected horses but only with CLCA1 in controls. The relationship between eqMUC5AC and CLCA1 differed in the 2 groups of horses with RAO-affected animals overexpressing CLCA1 in relation to eqMUC5AC.

CONCLUSIONS

These data implicate CLCA1 as a signalling molecule in the expression of eqMUC5AC in horses but also suggest differential regulation by CLCA1 and EGFR between horses with RAO and those with milder degrees of airway inflammation.

A novel technique for selective NF-kappaB inhibition in Kupffer cells: contrary effects in fulminant hepatitis and ischaemia-reperfusion

BACKGROUND AND AIMS

The transcription factor nuclear factor kappa B (NF-kappaB) has risen as a promising target for anti-inflammatory therapeutics. In the liver, however, NF-kappaB inhibition mediates both damaging and protective effects. The outcome is deemed to depend on the liver cell type addressed. Recent gene knock-out studies focused on the role of NF-kappaB in hepatocytes, whereas the role of NF-kappaB in Kupffer cells has not yet been investigated in vivo. Here we present a novel approach, which may be suitable for clinical application, to selectively target NF-kappaB in Kupffer cells and analyse the effects in experimental models of liver injury.

METHODS

NF-kappaB inhibiting decoy oligodeoxynucleotides were loaded upon gelatin nanoparticles (D-NPs) and their in vivo distribution was determined by confocal microscopy. Liver damage, NF-kappaB activity, cytokine levels and apoptotic protein expression were evaluated after lipopolysaccharide (LPS), d-galactosamine (GalN)/LPS, or concanavalin A (ConA) challenge and partial warm ischaemia and subsequent reperfusion, respectively.

RESULTS

D-NPs were selectively taken up by Kupffer cells and inhibited NF-kappaB activation. Inhibition of NF-kappaB in Kupffer cells improved survival and reduced liver injury after GalN/LPS as well as after ConA challenge. While anti-apoptotic protein expression in liver tissue was not reduced, pro-apoptotic players such as cJun N-terminal kinase (JNK) were inhibited. In contrast, selective inhibition of NF-kappaB augmented reperfusion injury.

CONCLUSIONS

NF-kappaB inhibiting decoy oligodeoxynucleotide-loaded gelatin nanoparticles is a novel tool to selectively inhibit NF-kappaB activation in Kupffer cells in vivo. Thus, liver injury can be reduced in experimental fulminant hepatitis, but increased at ischaemia-reperfusion.

Pre-transplant risk factors affecting outcome in Hurler syndrome

Allogeneic transplantation remains the standard of care for patients with Hurler syndrome. As enzyme replacement therapy (ERT) has become available, controversy has emerged in regards to whether the use of enzyme in the peri-transplant period is appropriate. An analysis was performed on 74 patients with Hurler syndrome transplanted at the University of Minnesota between 1990 and 2003, before our use of ERT associated with transplant, with the intention of determining if patients at higher risk during the transplant can be identified based on evaluations and events before transplantation. Age, the presence of hydrocephalus, a history of cardiovascular issues or upper airway obstruction before transplant was not associated with significant differences in survival. In contrast, patients who had a history of lower airway disease, including reactive airway disease or bronchiolitis, or a history of pneumonia, had a significantly inferior outcome based on OS. The risk for serious respiratory complications was also assessed by evaluating the incidence of intubation. Overall, 31% of these patients were intubated. The risk of intubation was higher in older patients and in those with a history of lower airway disease. These findings have implications for the care of patients with high-risk features.