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Pollen feeding in the honeybee (Apis mellifera) is dependent on the caste, ethotype, and dominance status of individuals. Pollen is the near-exclusive external source of lipids for the colony. Lipids from pollen are rich in polyunsaturated fatty acyl residues, which, because of their sensitivity to lipid peroxidation, have been suggested to limit the lifespan of individual bees. We here investigated whether the spectrum of phosphatidylcholine (PC), the main class of membrane-constituting lipids in insects, is indeed, connected to pollen feeding. We further studied the relationship between pollen feeding, PC spectra, and fat-body stores of vitellogenin, an indicator of potential longevity in bees. For this, we determined the pollen consumption, PC spectra, abdominal vitellogenin stores, and behavioral as well as reproductive status of individuals in queenless groups of workers. In contrast to earlier studies, we found that reproduction in workers is not universally linked to trophallactic dominance alone, but can be accompanied by strong pollen consumption. Pollen consumption seemed connected to a strong remodeling of tissue PC spectra. There was no systematic link between these spectra and trophallactic activity, but individuals with strongly deviating spectra also showed extreme behavioral profiles. Abdominal vitellogenin was strongly and positively linked to pollen-influenced PC spectra and the prevalence of polyunsaturated fatty acyl residues, contradicting the hypothesis that pollen consumption is systematically leading to a shorter lifespan in workers. Our results suggest that the association between pollen consumption, short lifespan, and functional sterility that differentiates workers from queens cannot in all cases be extended to the situation within the worker caste. [ABSTRACT FROM AUTHOR]

Allogeneic stem cell transplantation is a treatment option for patients with poor risk CLL. We conducted a retrospective analysis of all CLL patients allografted at our institution, the University Hospital of Cologne, Germany. Data was collected on 40 patients from 2004 to 2012. The mean age was 54, and the majority were male (75 %). On average, the patients were diagnosed 6 years (range 2-12) prior to transplant with an average of 4 years (range 1-8) from time of first-line therapy to transplant. The remission states at the time of transplant were complete remission (CR) ( n = 4), stable disease ( n = 10), partial remission ( n = 20) and progressive disease ( n = 6). Only reduced intensity conditioning regimens were employed. The average CD34 cell dose was 4.16 × 10/kg. Neutrophil engraftment was seen by day +17 (range 10-23) post-transplant, and 88 % achieved 95-100 % donor chimerism by day 100. Overall survival, progression-free survival and non-relapse mortality at 2 years post-transplant were 65, 52.5 and 27.5 %, respectively. A total of 51 % of patients were found to be minimal residual disease (MRD)-negative at 1 year post-transplant. Our single-centre experience confirms the valuable role of allogeneic stem cell transplantation (allo-SCT) in the treatment of poor risk CLL patients with promising long-term survival and acceptable transplant-related mortality. The advent of newer therapeutic agents should not hinder the consideration of allo-SCT for this patient cohort as it remains the only curative option for these patients. [ABSTRACT FROM AUTHOR]

Background:The association between tumour measurements and survival has been studied extensively in early-stage and locally advanced non-small cell lung cancer (NSCLC). We analysed these factors in patients with advanced NSCLC.Methods:Data were derived from the E4599 trial of paclitaxel-carboplatin±bevacizumab. Associations between the Response Evaluation Criteria in Solid Tumors (RECIST) baseline sum longest diameter (BSLD), response rate, progression-free survival (PFS) and overall survival (OS) were evaluated using univariate and multivariable Cox regression models.Results:A total of 759 of the 850 patients (89%) in the E4599 trial had measurable diseases and were included in this analysis. The median BSLD was 7.5 cm. BSLD predicted OS (hazard ratio (HR) 1.41; P<0.001) and had a trend towards association with PFS (HR 1.14; P=0.08). The median OS was 12.6 months for patients with BSLD <7.5 cm compared with 9.5 months for BSLD 7.5 cm. This association persisted in a multivariable model controlling multiple prognostic factors, including the presence and sites of extrathoracic disease (HR 1.24; P=0.01). There was no association between BSLD and response rate.Conclusion:Tumour measurements are associated with survival in the E4599 trial. If validated in other populations, this parameter may provide important prognostic information to patients and clinicians. [ABSTRACT FROM AUTHOR]

The heparan sulfate 6-O-endosulfatase (SULF2) promotes growth and metastasis of solid tumors. We recently identified that cytosine methylation of the SULF2 promoter is associated with better survival of resected lung adenocarcinoma patients, and now also demonstrates a marginal improvement in survival of advanced non-small cell lung cancer (NSCLC) patients receiving standard chemotherapy (hazard ratio=0.63, P=0.07). Subsequent studies focused on investigating the effect of methylation on SULF2 expression and its genome-wide impact. The genes and pathways modulated by epigenetic inactivation of SULF2 and the effects on sensitivity to chemotherapy were characterized in vitro and in vivo. Silencing SULF2 through small interfering RNA or methylation primarily increased expression of interferon-inducible genes including ISG15, a marker for increased sensitivity to topoisomerase-1 inhibitors such as camptothecin (CPT). NSCLC cell lines with methylated SULF2 (SULF2M) express 60-fold higher ISG15 compared with SULF2 unmethylated (SULF2U) NSCLC cell lines and normal human bronchial epithelial cells. In vitro, SULF2M and high ISG15 (ISG15H)-expressing NSCLC cell lines were 134-fold more sensitive to CPT than SULF2U and low ISG15 (ISG15L)-expressing cell lines. Topotecan, a soluble analog of CPT and FDA-approved anticancer drug, dramatically arrested the growth of SULF2M-ISG15H, but not SULF2U-ISG15L lung tumors in nude mice (P<0.002). Similarly, high ISG15 expression that is comparable to the topotecan (TPT)-sensitive NSCLC cell lines was found in tumors from 25% of NSCLC patients compared with normal lung, indicating a potential to identify and target the most sensitive NSCLC subpopulation for personalized TPT therapy. [ABSTRACT FROM AUTHOR]

The use of 5-methylcytosine demethylating agents in conjunction with inhibitors of histone deacetylation may offer a new therapeutic strategy for lung cancer. Monitoring the efficacy of gene demethylating treatment directly within the tumour may be difficult due to tumour location. This study determined the positive and negative predictive values of sputum and serum for detecting gene methylation in primary lung cancer. A panel of eight genes was evaluated by comparing methylation detected in the primary tumour biopsy to serum and sputum obtained from 72 patients with Stage III lung cancer. The prevalence for methylation of the eight genes in sputum (21-43%) approximated to that seen in tumours, but was 0.7-4.3-fold greater than detected in serum. Sputum was superior to serum in classifying the methylation status of genes in the tumour biopsy. The positive predictive value of the top four genes (p16, DAPK, PAX5 beta, and GATA5) was 44-72% with a negative predictive value for these genes > or =70%. The highest specificity was seen for the p16 gene, and this was associated with a odds ratio of six for methylation in the tumour when this gene was methylated in sputum. In contrast, for serum, the individual sensitivity for all genes was 6-27%. Evaluating the combined effect of methylation of at least one of the four most significant genes in sputum increased the positive predictive value to 86%. These studies demonstrate that sputum can be used effectively as a surrogate for tumour tissue to predict the methylation status of advanced lung cancer where biopsy is not feasible. [ABSTRACT FROM AUTHOR]

Using MALDI-TOF mass spectrometry, we have shown that leukocytic myeloperoxidase (MPO) in the presence of its substrates (H2O2 and Br−) does not induce any changes in saturated 1,2-dipalmitoyl- sn-glycero-3-phosphocholine. Incubation of liposomes prepared from mono-unsaturated phosphatidylcholine (1-palmitoyl-2-oleoyl- sn-glycero-3-phosphocholine) with the (MPO + H2O2 + Br−) system resulted in formation of bromohydrins as the main products. 1-Palmitoyl-2-hydroxy- sn-glycero-3-phosphocholine (lysophosphatidylcholine) was the main product of the reaction of polyunsaturated phosphatidylcholine (1-palmitoyl-2-arachidonoyl- sn-glycero-3-phosphocholine) with the (MPO + H2O2 + Br−) system. The formation of lysophospholipids as well as of bromohydrins was not observed when the enzyme or one of its substrates (H2O2 or Br−) was absent from the incubation medium, or if an inhibitor of MPO (sodium azide) or hypobromite scavengers (taurine or methionine) were added. Thus, it can be postulated that the formation of bromohydrins as well as lysophospholipids by the (MPO + H2O2 + Br−) system results from reactions of hypobromite formed during MPO catalysis with double bonds of acyl chains of phosphatidylcholine. Such destructive processes may take place in vivo in membrane-or lipoprotein-associated unsaturated lipids in centers of inflammation. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: We evaluated the -174 IL-6 gene polymorphism as a risk factor for type 2 diabetes mellitus in a family-based analysis. Methods: We tested for associations between the -174 IL-6 G/C promoter polymorphism and fasting plasma glucose (FPG) and type 2 diabetes in a sample of 1,428 individuals from the largest 182 families in the National Heart, Lung and Blood Institute's Framingham Heart Study population. Results: A significant association was found with FPG (p=0.01) and log (FPG) (p=0.005) using a modified family-based transmission disequilibrium test, the family-based association test (FBAT). The association between IL-6 genotype and FPG (p=0.035) and log (FPG) (p=0.03) was also found in the subset of families that were informative in FBAT using a mixed-effects regression model and strengthened after adjustment for potential confounders (p=0.008 for log [FPG]). The mean glucose level estimated from models with log (FPG) as the dependent variable for the GG genotype in the informative families was significantly lower (5.20±0.06 mmol/l) than for the GC (5.41±0.06 mmol/l) and CC (5.38±0.06 mmol/l) genotypes (p=0.03 for contrast between GG and GC genotypes). In the subset of informative families, the risk of type 2 diabetes associated with the GG genotype was lower relative to the GC and CC genotypes combined (potential confounder-adjusted, mixed-effects odds ratio 0.35, 95% CI 0.14–0.88, p=0.026, unaffected n=391, affected n=32). Conclusions/interpretation: These results are consistent with a protective role for the -174 IL-6 G allele against type 2 diabetes and warrant further analysis of this polymorphism. [ABSTRACT FROM AUTHOR]

Discusses key issues concerning the use of radiofrequency ablation as a non-invasive technique to treatment renal cell carcinoma. Patient selection; Tumor selection; Implications on studies of cancer and imaging systems in medicine.

To understand the viscoelastic properties of cartilage tissue and for the development of tissue-engineered cartilage, we have studied the physicochemical properties of bovine nasal and pig articular cartilage by13C nuclear magnetic resonance (NMR) methods. The major macromolecular components of cartilage can be investigated individually by applying13C high-resolution (HR) NMR with scalar decoupling (for the polysaccharide component) and solid-state NMR with dipolar decoupling (for the collagen component). Partially resolved NMR spectra of the cartilage polysaccharides can be obtained by HR13C NMR indicating that these polysaccharides are highly mobile. Resonance lines have been assigned to chondroitin sulfate, the most mobile component of cartilage. To characterize time scales of molecular motions, we have measured T 1 and T 2 relaxation times as a function of temperature and analyzed these data by means of a broad distribution of molecular correlation times. Typical correlation times for the large amplitude motions of chondroitin sulfate are of the order of 0.1–10 ns. For the detection and dynamical characterization of the cartilage collagen cross-polarization magic angle spinning (CP MAS) and high-power decoupling are indispensable.13C CP MAS spectra of cartilage are dominated by resonances from rigid collagen, while only low-intensity signals from the polysaccharides are observed. The good sensitivity at a magnetic field strength of 17.6 T allows the site-specific investigation of cartilage collagen dynamics by two-dimensional NMR methods. The cartilage collagen is essentially rigid with low-amplitude segmental motions on the fast time scale. Considering the high water content of cartilage and the almost isotropic mobility of the chondroitin sulfate molecules it is remarkable how little this affects the collagen dynamics. The dynamics of cartilage macromolecules is broadly distributed from almost completely rigid to highly mobile, which lends cartilage its mechanical strength and shock-absorbing properties. [ABSTRACT FROM AUTHOR]

The interaction between unsaturated phosphatidylcholines and either exogenous or endogenous (produced by the enzyme system involving myeloperoxidase (MPO), H2 O2 ,and Cl–) hypochlorite was studied in multilayer liposomes containing oleic, linoleic, and arachidonic acid residues using MALDI TOF mass spectrometry. At pH 7.4, hypochlorite reacts with the double bond of the oleic acid residue in 1-stearoyl-2-oleoyl- sn-glycero-3-phosphocholine producing oleic acid chlorohydrin as the main product. Minor amounts of glycols and epoxides were also detected. The main products of the reaction of hypochlorite with 1-stearoyl-2-oleoyl- sn-glycero-3-phosphocholine were mono and di chlorohydrins of linoleic acid. The signals of monoglycol, epoxide, and glycol or epoxide containing monochlorohydrin derivatives were also present in the mass spectrum. The main products of the reaction of hypochlorite with 1-stearoyl-2-oleoyl- sn-glycero-3-phosphocholine were lysophosphatidylcholine (1-stearoyl-2-oleoyl- sn-glycero-3-phosphocholine) and mono-, di-, and trichlorohydrin. Monoglycol and its derivatives containing one or two chlorohydrin groups were also detected. Along with those, carbonyl compounds (aldehyde and acid) formed as a result of double bond breakage in fifth position of arachidonate were detected. Monochlorohydrin was also found when liposomes comprising 1-stearoyl-2-oleoyl- sn-glycero-3-phosphocholine were incubated in the presence of enzymatic mixture, MPO +H2 O2 +Cl–,at pH 6.0. In the absence of the enzyme or either of its substrates (H2 O2 or Cl–) or in the presence of the MPO inhibitor (sodium azide) or hypochlorite scavengers (taurine or methionine), monochlorohydrin formation was not observed. These data confirm the suggestion that just the hypochlorite generated in MPO catalysis provides for chlorohydrin formation. Thus, the use of MALDI TOF mass spectrometry has shown, along with chlorohydrins, glycols and epoxides as the products of hypochlorite interaction with unsaturated phosphatidylcholines at physiological pH. It was first determined that hypochlorite breaks double bonds in polyunsaturated phosphatidylcholine and also causes lysophosphatidylcholine formation. [ABSTRACT FROM AUTHOR]

In this study, the pulsed field gradient (PFG) nuclear magnetic resonance (NMR) technique was used for the investigation of (1) concentration and compression effects on cation self-diffusion, and (2) restricted diffusion of cations in cartilage. Since physiologically relevant cations like Na[sup +] are difficult to investigate owing to their very short relaxation times, the cations tetramethylammonium (TMA) and tetraethylammonium (TEA) were employed for diffusion studies in samples of explanted cartilage. Results indicated that the diffusion of monovalent cations shows strong similarities to observations already made in studies of the diffusion of water in cartilage: with increasing compression, i.e. decreasing water content, the diffusion coefficient of the cation decreases concomitantly. The diffusion coefficients also showed a decrease with increasing cation concentrations, basically reflecting the corresponding decrease in the water content. Both results could be explained by the well-established model of Mackie and Meares. This, together with the similarity of the diffusion coefficient D in cartilage relative to free solution (about 50%) for both cations, is consistent with the view that the water content and not the charge is the most important determinant of the intratissue diffusivity of monovalent cations. Diffusion studies with increasing observation times showed strong evidence of restricted diffusion, allowing the estimation of the geometry of barriers within cartilage. [ABSTRACT FROM AUTHOR]

Glucose oxidase was attached to platinum-platinum oxide screens via alkylamine silaneglutaraldehyde coupling. The amount of immobilized enzyme was equivalent to 0.0031 µg of soluble glucose oxidase per cm of screen surface. The platinum-silane-glutaraldehydeenzyme screens were tested potentiometrically in buffered glucose solutions, with respect to a Ag/AgCl reference electrode. The results were expressed as the difference in potential for the enzyme screens placed in buffer containing glucose and placed in plain buffer. This difference in potential was related linearily to the logarithm of the glucose concentration over the range 5-150 mg glucose/100 ml. The source of the potential may be due to the decomposition of hydrogen peroxide produced by the glucose oxidase catalyzed oxidation of glucose. The approach is being studied for possible development of an implantable sensor for continuous in vivo monitoring of glucose levels. [ABSTRACT FROM AUTHOR]

Although matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS) was so far scarcely used in phospholipid (PL) analysis, this technique has a great potential: It is fast and reliable, spectra can be quantified and fragmentation of analytes is negligible. However, individual PL are detected in mixtures with different sensitivities: PL with quatemary ammonia groups are most sensitively detectable while further PL may be suppressed. Therefore, an initial separation of the PL mixture into the individual PL classes is required to be able to detect all PL. It is the aim of this paper to show on the hand of organic extracts of pig brain as a typical lipid mixture that MALDI-TOF MS in combination with TLC enables the detection of all relevant brain PL. However, it will also be shown that there are problems with the analysis of alkenyl-acyl compounds (plasmalogens) since they decompose in the presence of traces of acids as well as the acidic groups on the TLC plate under formation of the corresponding lysophospholipids. [ABSTRACT FROM AUTHOR]