Measurement of the interior structure of thin polymer films using grazing incidence diffuse x-ray scattering

A method is developed for calculating the small-angle x-ray scattering originating from within the interior of a thin film under grazing incidence illumination. This offers the possibility of using x-ray scattering to probe how the structure of polymers is modified by confinement. When the diffuse scattering from a thin film is measured over a range of incident angles, it is possible to separate the contributions to scattering from the interfaces and the contribution from the film interior. Using the distorted-wave Born approximation the structure factor, S(q), of the film interior can then be obtained. We apply this method to analyze density fluctuations from within the interior of a silicon supported molten polystyrene (PS) film. Measurements were made as a function of film thickness ranging from one to ten times the polymer radius of gyration (Rg). The compressibility, calculated by extrapolating the measured S(q) to q=0, agrees well with that of bulk PS for thick films, but thinner films exhibit a peak in S(q) near q=0. This peak, which grows with decreasing thickness, is attributed to a decreased interpenetration of chains and a consequent enhanced compressibility.

Prognostic value of perfusion MR imaging in patients with oligodendroglioma: A survival study

OBJECTIVE

The purpose of this study was to evaluate retrospectively whether cerebral blood volume measurement based on pretreatment perfusion MRI is a prognostic biomarker for survival in patients with oligodendroglioma or mixed oligoastrocytoma.

PATIENTS AND METHODS

Between 1998 and 2004, 54 patients (23 females and 31 males), aged 21-73 years, with oligodendroglioma (or mixed tumour) were examined prior to beginning treatment with dynamic susceptibility-weighted contrast (DSC) perfusion MRI during gadolinium first-pass. The relative cerebral blood volume (rCBV) was calculated by dividing the measurement within the tumour by the measurement of the normal-appearing contralateral region. Patients were classified in two groups, grade A and grade B, according to the Saint-Anne Hospital classification and followed-up clinically and by means of MRI until their death or for a minimum of 5 years. Patients were also classified in grade II and grade III-IV, according to the World Health Organisation (WHO) classification, and were analysed with the same methods. Age, sex, treatment, tumour grade, contrast agent uptake, and rCBV were tested using survival curves with Kaplan-Meier's method, and their differences were analysed using the log-rank test.

RESULTS

In this population, median survival was 3 years. A rCBV threshold value of 2.2 was validated as a prognostic factor, for survival in these patients with oligodendrogliomas. Age, sex, contrast uptake, and maximum rCBV were found to be prognostic factors in univariate analysis. Multivariate analysis revealed that tumour grade (grade A/grade B), rCBV, age, and sex were prognostic factors independent of the other factors. The tumour grade according to the WHO classification (II versus III-IV) was also detected as an independent prognostic factor.

CONCLUSION

Pretreatment rCBV measured by DSC perfusion MRI was found to be a prognostic factor for survival in patients with oligodendroglioma or mixed tumour, by using the Saint-Anne Hospital classification, which separate the IIB from the IIA.

Non-phytate phosphorus requirements and efficacy of a genetically engineered yeast phytase in male Lingnan Yellow broilers from 1 to 21 days of age

This experiment was conducted to investigate the requirement of non-phytate phosphorus (nPP) and efficacy of a genetically engineered yeast phytase in performance and tibia characteristics by male Lingnan Yellow broilers from 1 to 21 days of age. A total of 2640 1-day-old male chicks were randomly allotted to one of 11 dietary treatments, which consisted of six replicate floor pens with 40 birds per pen. All treatments had the same levels of all nutrients except for phosphorus and phytase. The control group (treatment 1) was fed the basal diet without dicalcium phosphate or phytase supplementation. Dietary concentrations of nPP were 0.11%, 0.19%, 0.27%, 0.35%, 0.43%, 0.51% and 0.59% respectively for treatments 1, 2, 3, 4, 5, 6 and 7, through addition of dicalcium phosphate (chemistry grade) to the basal diet. Diets 8-11 were supplemented with a genetically engineered yeast phytase 250, 500, 750 U/kg and a commercial phytase product 500 U/kg in basal diet respectively. The results showed that 0.46% and 0.51% nPP were required for maximum body-weight gain and optimum tibia development indicators respectively. However, 0.59% nPP had a negative effect on bird growth. The equivalency value of the genetically engineered yeast phytase was estimated to be 874 U/kg to liberate 0.1% nPP.

Examination of adipose depot-specific PPAR moieties

Molecular mechanisms of peroxisome proliferator activated receptors (PPARs) are being defined rapidly, as illustrated by the volume of papers published. Much of the research is directed towards a clinical end-point/application; however, the non-homogeneous nature of adipose depots in laboratory animals is spurring similar research in domestic meat animals (such as beef cattle). Moreover, the size of adipose depots in meat animals remains an attractive feature for using them to obtain cells for PPAR research. Examination of meat-animal depot-specific PPAR moieties may provide novel information about adipocyte regulation that might be extrapolated to all animals.

Antifungal activity of recombinant mouse beta-defensin 3

AIMS

To identify the presence of mouse beta-defensin 3 (Mbd3) (the human homologue of beta-defensin 2) in different tissues and to define the antimicrobial properties of recombinant MBD3 (rMBD3) against a panel of human pathogens.

METHODS AND RESULTS

Mbd3 gene expression in different mouse tissues before or after lipopolysaccharide (LPS) injection was compared by semi-quantitative RT-PCR. This analysis demonstrated that epithelial and mucosal tissues expressed Mbd3 independent of LPS stimulation. Evaluation of the antimicrobial properties of recombinant rMBD3 was determined by assessing the median inhibition concentration (IC(50)), minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC)/minimal fungicidal concentration (MFC) against various human pathogens.

CONCLUSION

Mbd3 gene expression by epithelial and mucosal tissues suggested that MBD3 likely plays an early defensive role against microbial infections. This activity was most significant against filamentous fungi.

SIGNIFICANCE AND IMPACT OF THE STUDY

The data presented in this report suggested that formulations containing rMBD3 and related molecules could serve to treat fungal and bacterial infections.

Interaction-induced shift of the cyclotron resonance of graphene using infrared spectroscopy

We report a study of the cyclotron resonance (CR) transitions to and from the unusual n=0 Landau level (LL) in monolayer graphene. Unexpectedly, we find the CR transition energy exhibits large (up to 10%) and nonmonotonic shifts as a function of the LL filling factor, with the energy being largest at half filling of the n=0 level. The magnitude of these shifts, and their magnetic field dependence, suggests that an interaction-enhanced energy gap opens in the n=0 level at high magnetic fields. Such interaction effects normally have a limited impact on the CR due to Kohn's theorem [W. Kohn, Phys. Rev. 123, 1242 (1961)], which does not apply in graphene as a consequence of the underlying linear band structure.

Symmetry breaking in the zero-energy Landau level in bilayer graphene

The quantum Hall effect near the charge neutrality point in bilayer graphene is investigated in high magnetic fields of up to 35 T using electronic transport measurements. In the high-field regime, the eightfold degeneracy in the zero-energy Landau level is completely lifted, exhibiting new quantum Hall states corresponding to filling factors nu=0, 1, 2, and 3. Measurements of the activation energy gaps for the nu=2 and 3 filling factors in tilted magnetic fields exhibit no appreciable dependence on the in-plane magnetic field, suggesting that these Landau level splittings are independent of spin. In addition, measurements taken at the nu=0 charge neutral point show that, similar to single layer graphene, the bilayer becomes insulating at high fields.

Gastrointestinal and Cardiovascular Safety Profiles of Neratinib Monotherapy in Patients with Advanced ErbB2-Positive Breast Cancer

Background: In a phase 2 study, oral neratinib was administered to patients (pts) with advanced breast cancer in 2 cohorts, those with prior trastuzumab treatment (prior T, n=66) and those with no prior trastuzumab treatment (no prior T, n=70). Neratinib demonstrated robust antitumor activity with objective response rates of 26% and 51%, respectively, and was generally tolerable (Burstein et al. Cancer Res 2009;69:72S). Diarrhea, all grades, occurred in 89% of total pts. Characteristics of the diarrhea and left ventricular ejection fraction (LVEF) measurements are described. Methods: Pts were required to have ErbB2 gene amplification in tumor tissue as measured by fluorescence in situ hybridization by independent assessment. Serial LVEF measurements were made with a multigated acquisition scan or echocardiogram. Pts were ineligible if baseline LVEF was <50%. Adverse events were graded based on the NCI Common Terminology Criteria, v 3.0. Pts received oral neratinib 240 mg daily. Results: Data collected by 18 Mar 2009 are reported; the median (range) duration of neratinib treatment was 4.5 (0.2-23.5) months for pts with prior T and 7.8 (0.5-24.2) months for pts with no prior T. Diarrhea, all grades occurred in 93% of the total population (prior T: 97%, no prior T: 89%); grade 3-4 diarrhea occurred in 21% of the total population (prior T: 30%, no prior T: 13%). Median times of onset were 2 and 3 days after first dose of neratinib, respectively, and median durations of diarrhea were 7 and 5 days. In study week 1, 86% and 73% of pts with prior T and no prior T, respectively, had diarrhea; this decreased to 12-14% in months 3 and 4 (Table). Diarrhea was the cause of dose interruptions in 36% of pts with prior T and 11% of pts with no prior T and of dose reductions in 30% of pts with prior T and 5% of pts with no prior T; only 1 pt (prior T) discontinued treatment due to diarrhea. Pts used anti-diarrheal medications for supportive therapy (prior T: 91%, no prior T: 67%). For LVEF measurements, there was little variation from baseline in most pts during the study. Four pts had at least 1 LVEF measurement <50% (2 of these pts had measurements within the institutional range of normal). None had congestive heart failure. One of these pts had grade 3 atrioventricular block and grade 3 bradycardia, which were considered unrelated to neratinib. Discussion: Neratinib treatment was not associated with clinically significant cardiotoxicity. Pts who developed diarrhea with neratinib monotherapy had early onset, but frequency and severity decreased with time on study. Despite the high frequency of diarrhea with neratinib treatment, it was readily managed with supportive therapy and dose interruptions and/or reductions.Time Course of Diarrhea in ErbB2-Positive Breast Cancer Patients Treated With NeratinibStudy PeriodPrior T: No. on StudyPrior T: % With Diarrhea, All Grades*Prior T: % With Diarrhea, Gr 3-4*No Prior T: No. on StudyNo Prior T: % With Diarrhea, All Grades*No Prior T: % With Diarrhea, Gr 3-4*Week 166861770737Week 2-466611170436Month 260331066152Month 34713060120Month 44312058140*For pts with multiple toxicity grades in a period, the maximum grade was reported.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5096.

RACK1, a potential target to decrease morphine reward in mice

Morphine reexposure induces the decrease of receptor for activated C-kinase 1 protein (RACK1) levels in frontal cortex, and the increase of p-ERK (extracellular signal-regulated kinase) levels in mouse frontal cortex, striatum, hippocampus and nucleus accumbens (NAcc). Moreover, RACK1 is associated with the core kinases of the ERK pathway, Raf, MEK, and ERK. The purpose of this study is to investigate the effect of overexpression of RACK1 on the conditioned place preference (CPP) and the level of p-ERK in morphine reexposure mice. Mice were subcutaneously injected with morphine on the 2nd, 4th, 6th, and the 8th day, saline was delivered the next day. After mice showed place preference, RACK1 was administered by intraventricular injection 20 minutes after injection of morphine on the 11th, 13th, 15th, and 17th day. CPP was measured on the 18th day. It was found that morphine reexposured mice showed a decreased RACK1 level in the frontal cortex, striatum and an increased RACK1 level in hippocampus and NAcc, but this effect was reversed after administration of RACK1. In this study we demonstrated that RACK1 decreased p-ERK and erased CPP during reexposure of morphine and there was no an effect in reexposure saline mice. It strongly suggests that RACK1 may play a crucial role in morphine reexposured mice and the RACK1 has the potential to be a remedy to the morphine reward.

Exercise training improved insulin sensitivity and ovarian morphology in rats with polycystic ovary syndrome

Hyperandrogenism and hyperinsulinemia are major clinical features in women with polycystic ovary syndrome (PCOS). We hypothesized that serum insulin levels reduced by exercise could relieve hyperandrogenism and ameliorate polycystic ovarian morphology. Wistar female rats with 21-day-old were randomly divided into three groups: PCOS exercise (P-Ex), PCOS sedentary (P-Sed), and control sedentary (C-Sed). The rats with PCOS were induced by injection with testosterone propionate continuously. The exercise program was to swim with 120 min/d for two weeks. Fasting blood glucose (FBG) and insulin (FINS), estrogen (E (2)), progesterone (P), and testosterone (T) in serum were determined by RIA, and ovarian morphology was evaluated by Image-Pro Plus 6.0. The levels of FINS, E (2), and T in serum were significantly lower in P-Ex than in P-Sed. The ratios of FBG/FINS in P-Ex significantly increased in comparison with P-Sed. The levels of serum sex hormones in P-Ex were similar to C-Sed. There were no differences in blood glucose and serum progesterone among three groups. Ovarian morphology showed that the numbers of preantral follicles and atretic follicles significantly decreased, and the numbers of antral follicles and corpora lutea significantly increased in P-Ex compared with P-Sed. The changes of ovarian morphology in P-Ex were similar to C-Sed. These results demonstrated that short-term exercise training can improve insulin sensibility, decrease serum androgen levels, and recover normal ovarian morphology. The exercise training is the basic therapeutic means for PCOS.

An open-label expanded access study of lapatinib and capecitabine in patients with HER2-overexpressing locally advanced or metastatic breast cancer

BACKGROUND

The Lapatinib Expanded Access Program (LEAP) was designed to provide access to lapatinib plus capecitabine for HER2-positive metastatic breast cancer patients who previously received an anthracycline, a taxane, and a trastuzumab and had no other treatment options.

PATIENTS AND METHODS

LEAP opened globally and enrollment continued until lapatinib received regulatory approval in each participating country. Patients were assessed for progression-free survival (PFS) and overall survival (OS) and monitored for serious adverse events (SAEs).

RESULTS

As of 30 September 2008, 4283 patients from 45 countries enrolled in LEAP. The median treatment duration was 24.7 weeks. The most common drug-related SAEs were diarrhea (9.7%), vomiting (4.3%), and nausea (2.4%) and were mainly grade 3 or higher. The incidences of special interest SAEs were decreased left ventricle ejection fraction (0.5%), interstitial lung disease/pneumonitis (0.2%), and serious hepatobiliary events (0.4%). This safety profile is consistent with the overall lapatinib program. The median PFS and OS were 21.1 [95% confidence interval (CI) = 20.1-22.3] and 39.6 (95% CI = 37.7-40.7) weeks, respectively (n = 4006). Subgroup analysis showed longer PFS and OS in patients who had not received prior capecitabine.

CONCLUSIONS

These results demonstrate the safety and efficacy of lapatinib in a broader patient population compared with a clinical trial.