A Study on the Reactive Compatibilization of a PBT/LCP Blend: Catalyst Effect

The in situ compatibilization of poly(butylene terephthalate) (PBT) with liquid crystalline polymer (LCP) via catalyzed transesterification reaction was examined through thermal, rheological, morphological and mechanical studies. The addition of catalyst, dibutyltindilaurate, was found to promote the transesterification between PBT and LCP. Maintenance of high vacuum environment was required to produce the high molecular weight copolymers in the reactor, which, acting at the interface, diminished the size of the dispersed phase (LCP) and enhanced interfacial adhesion that led to an early increase of the flexural strength. Flexural strength was reduced after long time reaction due to the chain scission. Transesterification confirmed by NMR spectroscopic analysis played a major role in the interchange process.

Disability in atypical parkinsonian syndromes is more dependent on memory dysfunction than motor symptoms

BACKGROUND

There is a gap in the systematic description and investigation of functional disability in corticobasal syndrome (CBS) and progressive supranuclear palsy (PSP). Additionally, the relations between disability, apraxia, cognitive and behavioural changes are not well understood in atypical parkinsonian syndromes.

METHODS

Fifty patients were included in this study (CBS = 18; PSP = 11), including a subgroup of primary progressive aphasia-nonfluent variant (PPA-nfv = 21) who were used as a control group given the clinic-pathological overlap. Functional disability (basic and instrumental activities of daily living), general cognition and behavioural changes were evaluated at baseline, with a subgroup of patients being reassessed after 16 months.

RESULTS

The corticobasal syndrome group had the most marked disability in basic activities in comparison to progressive supranuclear palsy and primary progressive aphasia-nonfluent variant. Longitudinal decline was marked for all three groups. In a linear regression examining factors behind functional disability in CBS and PSP, memory dysfunction emerged as the main factor (48.5%), followed by apraxia (14.9%) and atypical parkinsonian symptoms (9.6%).

CONCLUSIONS

Memory dysfunction is the most important factor in functional disability in CBS and PSP, which has to be taken into consideration in disease management, prognosis and planning of services to fully address patients' and families' needs.

Effects of Korean ginseng berry extract on sexual function in men with erectile dysfunction: a multicenter, placebo-controlled, double-blind clinical study

Ginseng is beneficial for many aspects of human physiology, including sexual function. In this study, we have evaluated the efficacy and safety of an extract of ginseng berry, which has a ginsenoside profile distinct from other parts of the plant, on sexual function in men with erectile dysfunction. In all, 119 men with mild-to-moderate ED participated in a multicenter, randomized, double-blind, parallel, placebo-controlled clinical study. They were administered 4 tablets of either standardized Korean ginseng berry (SKGB, 350 mg ginseng berry extract per tablet), or placebo, daily, for 8 weeks. Efficacy was assessed with the International Index of Erectile Function (IIEF)-15 and premature ejaculation diagnostic tool (PEDT) at the end of the 4th and 8th week. We observed that the total and each of the individual domain scores of IIEF-15 increased from 40.95 ± 7.05 to 46.19 ± 12.69 significantly in the SKGB by the 8th week (P<0.05). The erectile function domain of IIEF changed slightly from 17.17 ± 2.57 to 18.59 ± 5.99 in the SKGB group by the 8th week (P<0.05). In addition, PEDT scores significantly improved from 9.14 ± 4.57 to 7.97 ± 4.4 and 7.53 ± 4.26 in the SKGB group after 4 and 8 weeks of treatment (P<0.05). Safety markers including hormone and lipid in the blood were assessed at the end of the 4th and 8th week and they remained unchanged. Oral administration of the SKGB extract improved all domains of sexual function. It can be used as an alternative medicine to improve sexual life in men with sexual dysfunction.

Activities of daily living in progressive non-fluent aphasia, logopenic progressive aphasia and Alzheimer's disease

BACKGROUND/AIMS

This study examined functional changes in progressive non-fluent aphasia (PNFA) and logopenic progressive aphasia (LPA) and Alzheimer's disease (AD) and the association between function, cognition and behaviour.

METHODS

59 patients were assessed with the Disability Assessment of Dementia (DAD), Addenbrooke's Cognitive Examination Revised (ACE-R) and the Cambridge Behavioural Inventory Revised (CBI-R).

RESULTS

No differences between groups in basic and instrumental activities of daily living (ADLs), and total ACE-R scores were found; there were correlations between total DAD and ACE-R scores for PNFA and LPA. Over 12 months, PNFA showed the marked decline of basic ADLs, whereas all three groups showed marked decline of instrumental ADLs.

CONCLUSION

PNFA, LPA and AD appear functionally similar when matched for disease duration. The rate of decline of ADLs depends, however, on disease diagnosis.

Formation of nano-sized Y2O3 dispersoids in mechanically alloyed Ni-(Cr, Y2O3, Y) alloys during heat-treatments

In the present work, the evolution of nanoparticles during annealing and hot-consolidation in mechanically alloyed Ni-22Cr-1.5Y, Ni-22Cr-1.5Y2O3 and Ni-3% Y2O3 was examined. The high-energy ball-milling of elemental powders resulted in the complete dissolution of the constituent Cr, Y, or Y2O3, forming a Ni-based solid solution. During the subsequent annealing, however, oxide particles precipitated from the solid solution. In the case of mechanically alloyed Ni-22Cr-1.5Y2O3, over-grown Cr2O3 precipitated at a temperature as low as above approximately 500 degrees C and ternary YCrO3 particles precipitated at 1100 degrees C. In the case of mechanically alloyed Ni-22Cr-1.5Y, on the other hand, the binary Y2O3 phase precipitated at 1100 degrees C during spark plasma sintering. The presence of Cr in the alloy composition facilitated the formation of Cr2O3 or YCrO3, and the precipitated oxides were highly prone to grain growth during hot-consolidation, sometimes reaching several micrometers. In Cr-exempt Ni-3%Y or Ni-3% Y2O3, however, the growth of nanodispersoids was restrained even at temperatures as high as 1000 degrees C and the resulting dispersoid was only nano-sized Y2O3.

Formation of nanostructures in Ni-22Cr-11Fe-1X (X = Y2O3, TiO2) alloys by high-energy ball-milling

Powder mixtures of Ni, Cr, Fe and Y2O3 were high-energy ball-milled and subsequently sintered to fabricate Ni-based oxide-dispersion strengthened (ODS) alloys. Nano-sized Y2O3 and/or TiO2 seem to be dissolved in the Ni matrix forming a metastable solid solution during high-energy ball-milling or mechanical alloying (MA) process. The finely grained MA powders with high dislocation density facilitated the decomposition of oxides. The MA powders were consolidated to near-full density by spark plasma sintering at 1100 degrees C for 5 minutes in an Ar atmosphere. The Cr oxides as well as decomposed Y- and Ti-oxides thermally precipitated as oxide particles of several tens nanometers at this temperature, although sintering was carried out during a short time. The SPSed specimen showed a near full densification with almost pore-free microstructures. Examination of fractured surface showed a typical dimple rupture with fine and homogeneous distribution of dispersoids, indicating non-negligible room temperature ductility combined with high mechanical strength.

Phase III study of gemcitabine/oxaliplatin (GEMOX) with or without erlotinib in unresectable, metastatic biliary tract carcinoma

LBA4032

Background: Currently, there is no standard regimen for palliative chemotherapy in metastatic, unresectable biliary tract cancer (BTC). A phase II trial of erlotinib monotherapy showed a promising anti-tumor activity in BTC with tolerable toxicity. Additionally, gemcitabine + erlotinib demonstrated superior efficacy when compared to gemcitabine alone in pancreatic cancer. Hence, we conducted a phase III trial to compare between GEMOX vs GEMOX+erlotinib (Tarceva [T]) (GEMOX/T) as first-line chemotherapy in unresectable, metastatic BTC. Methods: Eligible patients were as follows: histologically confirmed adenocarcinoma of biliary tract (CCC), ampulla of vater (AOV) or gall bladder (GB); unresectable or metastatic; ECOG performance status of 0~2; adequate marrow, hepatic, renal and cardiac functions; no prior chemotherapy. The primary endpoint was progression free survival (PFS). The study regimen was gemcitabine 1,000mg/m2, oxaliplatin 100mg/m2, erlotinib 100mg qd daily q 2 weeks. Results: From February 2009 to August 2010, 268 pts were randomized, 133 patients to GEMOX arm and 135 patients to GEMOX/T arm. Patient characteristics: median age 61 yrs (range 30-82); male (63.4%); CCC (n=180, 67.2%), GB (n=82, 30.6%), and AOV (n=6, 2.2%). With a median follow-up of 13.9 months (range, 6.7 – 25.0), median PFS was 5.8 months (95% CI, 4.6 - 7.0) in GEMOX/T arm and 4.2 months (95% CI, 2.7 - 5.7) in GEMOX arm (P=0.080). In subgroup analysis (CCC, n=180), however, median PFS was significantly longer in GEMOX/T arm (5.9 months) when compared with GEMOX arm (3.0 months, P=0.049). The overall response rate was significantly higher in the GEMOX/T arm when compared with GEMOX arm. There was no significant difference in overall survival between the two arms (GEMOX/T: 9.5 months, 95% CI, 7.6 – 11.4; GEMOX: 9.5 months, 95% CI, 7.5 – 11.5; P=0.611). The EGFR mutation testing results in correlation to responsiveness to erlotinib will be presented at the meeting. Conclusions: This phase III represents the first multicenter, randomized trial to compare GEMOX vs GEMOX/T in unresectable, metastatic BTC. Although PFS was not prolonged in GEMOX/T, there was a significant benefit in terms of PFS in GEMOX/T arm for CCC patients.

Distinct clinical and metabolic deficits in PCA and AD are not related to amyloid distribution

BACKGROUND/OBJECTIVE

Patients with posterior cortical atrophy (PCA) often have Alzheimer disease (AD) at autopsy, yet are cognitively and anatomically distinct from patients with clinical AD. We sought to compare the distribution of β-amyloid and glucose metabolism in PCA and AD in vivo using Pittsburgh compound B (PiB) and FDG-PET.

METHODS

Patients with PCA (n = 12, age 57.5 ± 7.4, Mini-Mental State Examination [MMSE] 22.2 ± 5.1), AD (n = 14, age 58.8 ± 9.6, MMSE 23.8 ± 6.7), and cognitively normal controls (NC, n = 30, age 73.6 ± 6.4) underwent PiB and FDG-PET. Group differences in PiB distribution volume ratios (DVR, cerebellar reference) and FDG uptake (pons-averaged) were assessed on a voxel-wise basis and by comparing binding in regions of interest (ROIs).

RESULTS

Compared to NC, both patients with AD and patients with PCA showed diffuse PiB uptake throughout frontal, temporoparietal, and occipital cortex (p < 0.0001). There were no regional differences in PiB binding between PCA and AD even after correcting for atrophy. FDG patterns in PCA and AD were distinct: while both groups showed hypometabolism compared to NC in temporoparietal cortex and precuneus/posterior cingulate, patients with PCA further showed hypometabolism in inferior occipitotemporal cortex compared to both NC and patients with AD (p < 0.05). Patients with AD did not show areas of relative hypometabolism compared to PCA.

CONCLUSIONS

Fibrillar amyloid deposition in PCA is diffuse and similar to AD, while glucose hypometabolism extends more posteriorly into occipital cortex. Further studies are needed to determine the mechanisms of selective network degeneration in focal variants of AD.

Effect of filler geometry on coefficient of thermal expansion in carbon nanofiber reinforced epoxy composites

This study involves the investigation of the geometry effect of nano-fillers on thermally induced dimensional stability of epoxy composites by experimentally evaluating the linear coefficient of thermal expansion (CTE). Carbon nanofibers (CNF) were chosen as the filler in epoxy matrix to investigate the effect of an aspect ratio on the CTE of the nanocomposites at three different volume fractions of 0.5, 1, and 2% of the nano-filler. The composites were fabricated using a mechanical mixing method. The CTE values were evaluated by measuring thermal strains of the composites and also compared with a micromechanics model. It was observed that the composites with short CNF (average L/d = 10) show better thermal stability than one of the composites with long CNF (average L/d = 70), and the thermal stability of the composites was proportional to the volume fraction of the filler in each composite. In addition, the CTE of mutliwalled carbon nanotubes (MWNT) reinforced epoxy composites was evaluated and compared with the CTE of the CNF reinforced composites. Interestingly, the MWNT reinforced composites show the greatest thermal stability with an 11.5% reduction in the CTE over the pure epoxy. The experimental data was compared with micromechanics model.

Development of murine leukemia virus-based retroviral vectors with a minimum possibility of cis-activation

The possibility of insertional mutagenesis in retroviral gene therapy can be reduced by using a vector lacking the enhancer sequence present in the U3 of the long-terminal repeats. However, such vectors suffer from many pitfalls. We attempted to improve a murine leukemia virus-based retroviral vector containing the enhancer-free U3, first by making it easier to construct a producer line and then by introducing the cellular RPL10 promoter as an internal promoter. The reverse orientation of the expression cassette of the transgene was found to give higher transducing titer and higher-level gene expression. The deletion analysis revealed that the 54-bp-long sequence of U3 (34 and 20 bp present at 5' and 3' extreme ends, respectively) was sufficient for the functions of retroviral vectors. The data from the in vitro cell culture assay indicated that the final construct, ROK, containing all these features, had little cis-activation activity, even if it was placed right upstream from the RNA start site of the neighboring gene. Our data suggested that the newly developed vector might provide increased safety, while still producing high viral titer from a stable producer line and high-level gene expression in various target cells including human CD34(+) stem cells.