Statistical iterative reconstruction for streak artefact reduction when using multidetector CT to image the dento-alveolar structures

OBJECTIVES

When metallic prosthetic appliances and dental fillings exist in the oral cavity, the appearance of metal-induced streak artefacts is not avoidable in CT images. The aim of this study was to develop a method for artefact reduction using the statistical reconstruction on multidetector row CT images.

METHODS

Adjacent CT images often depict similar anatomical structures. Therefore, reconstructed images with weak artefacts were attempted using projection data of an artefact-free image in a neighbouring thin slice. Images with moderate and strong artefacts were continuously processed in sequence by successive iterative restoration where the projection data was generated from the adjacent reconstructed slice. First, the basic maximum likelihood-expectation maximization algorithm was applied. Next, the ordered subset-expectation maximization algorithm was examined. Alternatively, a small region of interest setting was designated. Finally, the general purpose graphic processing unit machine was applied in both situations.

RESULTS

The algorithms reduced the metal-induced streak artefacts on multidetector row CT images when the sequential processing method was applied. The ordered subset-expectation maximization and small region of interest reduced the processing duration without apparent detriments. A general-purpose graphic processing unit realized the high performance.

CONCLUSIONS

A statistical reconstruction method was applied for the streak artefact reduction. The alternative algorithms applied were effective. Both software and hardware tools, such as ordered subset-expectation maximization, small region of interest and general-purpose graphic processing unit achieved fast artefact correction.

Observation of e+e- → γX(3872) at BESIII

With data samples collected with the BESIII detector operating at the BEPCII storage ring at center-of-mass energies from 4.009 to 4.420 GeV, the process e+e-→ γX(3872) is observed for the first time with a statistical significance of 6.3σ. The measured mass of the X(3872) is (3871.9 ± 0.7s tat ± 0.2 syst)  MeV/c(2), in agreement with previous measurements. Measurements of the product of the cross section σ[e+e- → γX(3872)] and the branching fraction B[X(3872)→π+π-J/ψ] at center-of-mass energies 4.009, 4.229, 4.260, and 4.360 GeV are reported. Our measurements are consistent with expectations for the radiative transition process Y(4260) → γX(3872).

The efficacy and safety of zibotentan in the treatment of castration-resistant prostate cancer: a meta-analysis

OBJECTIVE

Recently, novel endothelins like zibotentan and atrasentan and other novel taxanes have been introduced to treat prostate cancer. This study reviews zibotentan in the treatment of castration-resistant prostate cancer (CRPC) and derives a more precise estimate of their effect of treatment.

MATERIALS AND METHODS

Two reviewers searched and extracted data of the published trials and review articles on zibotentan for prostate cancer using the Medline, Embase and Cochrane Controlled Trials Register database. We used hazard ratios (HRs) to assess the effects on overall survival (OS), progression-free survival (PFS), or time to PSA progression (TTP), and relative risk (RR) for the different types of toxicity. Four randomized controlled trials were identified.

RESULTS

The pooled HR showed that zibotentan did not improve OS and PFS (HR = 0.92, 95%CI = 0.82-1.03, p = 0.161, HR = 0.98, 95% CI = 0.89-1.08, p = 0.714). Zibotentan had modest benefits on TTP (HR = 0.94, 95% CI = 0.91-0.97, p = 0.001). In addition, zibotentan led to more peripheral edema, anemia, cardiac failure and pneumonia.

CONCLUSIONS

Our study concludes that zibotentan is not an attractive option for CRPC patients. However, additional studies on other novel therapies are needed to improve patient outcomes.

Design of an ultrahigh-energy-resolution and wide-energy-range soft X-ray beamline

A new ultrahigh-energy-resolution and wide-energy-range soft X-ray beamline has been designed and is under construction at the Shanghai Synchrotron Radiation Facility. The beamline has two branches: one dedicated to angle-resolved photoemission spectroscopy (ARPES) and the other to photoelectron emission microscopy (PEEM). The two branches share the same plane-grating monochromator, which is equipped with four variable-line-spacing gratings and covers the 20-2000 eV energy range. Two elliptically polarized undulators are employed to provide photons with variable polarization, linear in every inclination and circular. The expected energy resolution is approximately 10 meV at 1000 eV with a flux of more than 3 × 10(10) photons s(-1) at the ARPES sample positions. The refocusing of both branches is based on Kirkpatrick-Baez pairs. The expected spot sizes when using a 10 µm exit slit are 15 µm × 5 µm (horizontal × vertical FWHM) at the ARPES station and 10 µm × 5 µm (horizontal × vertical FWHM) at the PEEM station. The use of plane optical elements upstream of the exit slit, a variable-line-spacing grating and a pre-mirror in the monochromator that allows the influence of the thermal deformation to be eliminated are essential for achieving the ultrahigh-energy resolution.

Intestinal dysbacteriosis contributes to decreased intestinal mucosal barrier function and increased bacterial translocation

The purpose of this study was to determine the effect of colistin-induced intestinal dysbacteriosis on intestinal mucosal barrier function and bacterial translocation in a mouse model. Colistin or saline was administered orally for 7 days, and populations of viable organisms from the caecal mucosa and its content, the ileal segments, the mesenteric lymph nodes (MLNs) and the internal organs were prepared for examination. In the intestinal dysbacteriosis model, intestinal barrier dysfunction was observed and associated with increased bacterial translocation to extraintestinal sites. The extent of bacterial translocation to the MLNs and internal organs in the colistin group was significantly higher than in the saline group. Colistin-induced intestinal dysbacteriosis was shown to injure the intestinal mucosa barrier function and increase bacterial dislocation.

SIGNIFICANCE AND IMPACT OF THE STUDY

Colistin has been reported to be effective in selective digestive decontamination (SDD), which is an infection prevention measure used in the treatment of certain patients in intensive care. We are the first to report that colistin-induced intestinal dysbacteriosis can injure intestinal mucosal barrier function and increase bacterial translocation, whereas a high dose of colistin does not damage the intestinal mucosal barrier in germ-free (GF) mice raised in a GF environment. These results may indicate that prolonged use of a high dose of a SDD medication should be carefully considered.

Abstract P5-09-05: Progranulin (GP88) expression and letrozole resistance in breast cancer

The 88 kDa glycoprotein GP88 (Progranulin, PCDGF, acrogranin) is the largest member of the granulin/epithelin family of growth modulators. GP88 was originally characterized in our laboratory through a biological screen to identify drivers of tumorigenesis. Published studies have established that GP88 represents an ideal therapeutic and diagnostic target in breast cancer (BC) leading to the development of validated tools to measure GP88 in tumor biopsies and biological fluids as well as blocking its action. It was shown that: 1) GP88 expression increases with tumorigenesis; 2) in ER+ breast cancer cells, GP88 stimulates proliferation and its overexpression confers estrogen independence and resistance to several anti-estrogens and aromatase inhibitor; 3) inhibition of GP88 expression by antisense transfection inhibited proliferation in vitro and in vivo; 4) In Her-2 overexpressing breast tumors, GP88 stimulated Her-2 phosphorylation and conferred trastuzumab resistance; 5) GP88 is expressed in 80% invasive ductal carcinoma (IDC) and 60% of ductal carcinoma whereas it is negative in lobular carcinoma, benign lesions and normal mammary tissues; 6) GP88 is secreted and can be detected in the serum of BC patients at an increased level when compared to healthy subjects; 7) Pathological studies with 530 cases of ER+ IDC with clinical outcomes showed that GP88 tumor expression was an independent prognostic indicator of recurrence in early stage BC patients. Training study followed by an independent validation study demonstrated that high GP88 tissue expression (GP88 3+) was associated with a 4-fold increase in risk of recurrence at 5 years.

Since GP88 displays not only diagnostic but also therapeutic potentials, we developed a neutralizing anti-GP88 antibody AG1 that inhibited GP88 biological effect (proliferation and migration) in a dose-dependent fashion in vitro. AG1 was expressed in a high yield CHO cell line and formulated. We have shown that in tamoxifen resistant cells, treatment with AG1 would inhibit tumor growth and restore tamoxifen sensitivity. The present study examined the effect of AG1 in letrozole resistant cells. We have developed from a letrozole sensitive cell ER+ BC cell line, a letrozole-resistant cell line by long term selection in letrozole-supplemented medium. This cell line (LetR) shows also decreased letrozole responsiveness in vivo and therefore constitutes an excellent model for investigating letrozole resistance in vivo as well as in vivo. Here we investigated the effect of various doses of AG1 on LetR tumor development alone or in combination with letrozole. Treatment with AG1 (10 mg/kg i.p.) in combination with letrozole was efficient to maintain long term responsiveness to letrozole and inhibited tumor growth. In addition to the mouse xenografts study, an IRB approved clinical study examines changes in GP88 circulating levels in patients with resistance to aromatase inhibitors. Preliminary data will be presented.

In conclusion, inhibiting GP88 could provide a novel and alternative therapeutic strategy for patients with resistance to anti-estrogen therapy, being tamoxifen or letrozole.

This work is supported by 2R44CA124179 and HHSN 261201200060C from NCI and 02- 2013-018 from the Avon Foundation for Women.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-09-05.

Differences in frequencies of UGT1A9, 1A7, and 1A1 genetic polymorphisms in Chinese Tibetan versus Han Chinese populations

As part of a series of pharmacogenomics studies of the Chinese population, we investigated genetic polymorphisms of some UGT1A regions. The three genes that were analyzed were UGT1A9, 1A7, and 1A1; we sequenced their exons, together with promoters, surrounding introns and 3'-untranslated regions (3'UTR) in 100 unrelated-healthy Chinese Tibetan individuals. We compared the data with information on Han Chinese of the same region, which we downloaded from the HapMap database. We identified 40 polymorphisms; 16 of them were shared by the two populations. We then analyzed their linkage disequilibrium map. The UGT1As cluster can be divided into two linkage blocks in the Tibetan population: Block 1 (UGT1A9, UGT1A7), Block 2 (3'-UTR). Furthermore, we identified haplotypes and selected their tagSNPs. In exon 1 of UGT1A7 gene, 393G>A (Arg131Gln, rs17868324) was found at a frequency of 44.4% in the Tibetan population, compared to only 0.7% in the Han population. The linkage blocks in the Han Chinese sample differed from that of the Chinese Tibetan group; the former had Block 1 (UGT1A9, UGT1A7), Block 2 (UGT1A7), and Block 3 (3'-UTR). These findings provide fundamental information for future molecular genetic studies of the UGT1A gene cluster as well as for personalized medicine in Chinese.

Contribution of an alveolar cell of origin to the high-grade malignant phenotype of pregnancy-associated breast cancer

Pregnancy-associated breast cancers (PABCs) are tumors diagnosed during pregnancy or up to 5 years following parturition, and are usually high-grade, connective tissue-rich, and estrogen receptor (ER)/progesterone receptor-negative. Little is known about the cellular origin of PABCs or the mechanisms by which PABCs are initiated. Using the RCAS retrovirus to deliver the ErbB2 oncogene into the mammary epithelium of our previously reported MMTV-tva transgenic mice, we detected high-grade, poorly differentiated, stroma-rich and ER-negative tumors during pregnancy and lactation. These high-grade and stroma-rich tumors were less frequent in involuted mice or in age-matched nulliparous mice. More importantly, by generating a WAP-tva transgenic line for expression of ErbB2 selectively in WAP(+) mammary alveolar cells, we found that tumors had similar morphological phenotypes (high grade, poorly differentiated, stroma-rich and ER-negative), irrespective of the time since pregnancy and even in the absence of pregnancy. These data suggest that PABCs arise preferentially from an alveolar cell population that expands during pregnancy and lactation. This somatic mouse model may also be useful for preclinical testing of new prophylactic and therapeutic strategies against PABC.

Cognitive trio: relationship with major depression and clinical predictors in Han Chinese women

BACKGROUND

Previous studies support Beck's cognitive model of vulnerability to depression. However, the relationship between his cognitive triad and other clinical features and risk factors among those with major depression (MD) has rarely been systematically studied.

METHOD

The three key cognitive symptoms of worthlessness, hopelessness and helplessness were assessed during their lifetime worst episode in 1970 Han Chinese women with recurrent MD. Diagnostic and other risk factor information was assessed at personal interview. Odds ratios (ORs) were calculated by logistic regression.

RESULTS

Compared to patients who did not endorse the cognitive trio, those who did had a greater number of DSM-IV A criteria, more individual depressive symptoms, an earlier age at onset, a greater number of episodes, and were more likely to meet diagnostic criteria for melancholia, postnatal depression, dysthymia and anxiety disorders. Hopelessness was highly related to all the suicidal symptomatology, with ORs ranging from 5.92 to 6.51. Neuroticism, stressful life events (SLEs) and a protective parental rearing style were associated with these cognitive symptoms.

CONCLUSIONS

During the worst episode of MD in Han Chinese women, the endorsement of the cognitive trio was associated with a worse course of depression and an increased risk of suicide. Individuals with high levels of neuroticism, many SLEs and high parental protectiveness were at increased risk for these cognitive depressive symptoms. As in Western populations, symptoms of the cognitive trio appear to play a central role in the psychopathology of MD in Chinese women.

Increased nucleobindin-2 (NUCB2) transcriptional activity links the regulation of insulin sensitivity in Type 2 diabetes mellitus

The protein nucleobindin-2 (NUCB2) has been recently identified as a novel satiety regulator. However, its pathophysiological role in humans remains unknown. The aims of the present study are to explore whether plasma NUCB2-1 and NUCB2 transcription activity are increased in newly diagnosed Type 2 diabetes mellitus (nT2DM) and, if so, whether changing NUCB2-1 level is a physiologic response or a compensatory mechanism for impaired insulin action. The nT2DM, impaired glucose tolerance (IGT), and healthy people (NGT, normal glucose tolerance) groups were enrolled in this study. The peripheral and hepatic insulin actions in rats with intracerebroventricular (ICV) NUCB2-1 administration were examined by euglycemic-hyperinsulinemic clamps. Plasma NUCB2-1 levels were elevated in subjects with both nT2DM and IGT compared with normal controls. NUCB2 mRNA and protein contents of muscle and adipose tissues in T2DM patients were also significantly increased compared to controls. ICV NUCB2-1 infusion in rats inhibited hepatic phosphoenolpyruvate carboxykinase (PEPCK) activity, and this was sufficient to induce insulin sensitivity in the liver and peripheral tissues during euglycemic-hyperinsulinemic clamps. In T2DM patients, there were increases in plasma NUCB2-1 levels and increases in NUCB2 mRNA and protein contents in muscle and adipose tissues. These increases are presumably a compensatory response to defective insulin action.

A comparison of serum and sputum inflammatory mediator profiles in patients with asthma and COPD

OBJECTIVE

To investigate serum and sputum cytokine profiles in asthma and chronic obstructive pulmonary disorder (COPD).

METHODS

Clinical characteristics, blood and sputum samples were collected from asthma (n = 37) and COPD (n = 36) patients, and healthy subjects (n = 39). Cytokines were measured by enzyme-linked immunosorbent assay (ELISA) and inflammation antibody array; levels were analysed according to smoking status and presence of eosinophilia in the airways of COPD/asthma patients, and compared with those in healthy subjects.

RESULTS

ELISA revealed a significant difference in the expression of only a few cytokines in the COPD versus asthma groups, and in both patient groups compared with healthy subjects. The antibody array showed greater differentiation in inflammatory mediators. In the subphenotype analysis, the differential expression of cytokines was more significant between eosinophilic and noneosinophilic airway inflammation than between asthma and COPD, according to both the ELISA and antibody array. There was little difference in cytokine expression between smoking and nonsmoking subgroups.

CONCLUSIONS

Differential expression of inflammatory mediators is present between patients with COPD or asthma, and eosinophilic or noneosinophilic airway inflammation, and contributes to understanding the cytokine network of airway inflammation.

Cantharidin as an antitumor agent: a retrospective review

This review summarizes the progress that has been made recently in the medicinal chemistry of cantharidin, a potent antitumor agent from traditional Chinese medicine. Thousands of analogs have been synthesized on the basis of cantharidin, a part of which shows excellent properties, in particular, norcantharidin and norcantharimide. Despite the enormous efforts made, the intriguing bioactivities, mechanism, indications, and their interplay are still ill-defined. This review provides our up-to-date understanding in connection with the therapeutic use, mechanism, structure-activity relationship (SAR) and interesting properties of cantharidin analogs. Considerable development in the design of cantharidin analogs, in combination with mechanistic studies, has laid a foundation for transforming novel antitumor drugs into the clinic.

Effect of aminoguanidine intervention on neutrophils in diabetes inflammatory cells wound healing

To explore aminoguanidine (AG) effect on neutrophil functions and associated signal transduction way in diabetic rats wound healing. Sprague-Dawley (SD) rats were divided into 3 groups, Group A (control+burns), Group B (diabetes+burns), Group C (diabetes+burns+AG). Wound skin tissue was harvested at 6h, 24h and 36h after trauma, and then immunohistochemistry was used to detect AGE (advanced glycation end products) contents and RAGE (receptor of AGE) expression. Western blotting was applied to detect RAGE and NF-κB. Oxidative stress changes were detected by colorimetry. Inflammatory cytokines were determined by ELIASA and cell apoptosis by TUNEL. Pathological changes were analyzed by hematoxylin-eosin (HE) staining. In the wound tissue of Group C, compared to that in Group B, AGE content, RAGE expression level, NF-κB level declined, and MPO (myeloperoxidase) decreased at 36h; TNFα, IL-8, H2O2, GSH-Px (Glutathione peroxidse), and MDA (malondialdehyde) levels increased; dense post-traumatic inflammation belt formed obviously. AG for prophylactic use can promote the migration and respiratory burst of neutrophils markedly, and help to restore the functions of neutrophil; and the abnormal secretion of inflammation cytokines can be corrected partly. Blocking AGE deposition and promoting microenvironment were effective ways for diabetic wound healing.

Optimal conditions for "heat-conduct effect" in liver tissue during radiofrequency ablation

AIM

This study was conducted to optimize the "heat-conduct effect" to increase the efficacy of radiofrequency ablation (RFA) in the treatment of liver tumors.

METHODS

To simulate the "heat-conduct effect" caused by RFA, isolated pig livers were heated by an inserted metal tube through which water with different incoming temperatures was passed. The tissue temperature was measured within 5- and 10-mm radiuses. Further, changes in color and morphology of the tissue were recorded.

RESULTS

Using an incoming temperature of 70 °C, the effective ablation radius of 5 mm was achieved within 10 min. To expand the effective radius to 10 mm, the tube temperature needed to be maintained at above 80 °C for 40 min; alternatively, the tube temperature above 90 °C and heating time of 25 min were also sufficient.

CONCLUSION

To achieve the complete ablation in isolated liver within the 10 mm radius by "heat-conduct effect", the temperature of the heating center should be maintained above 80 - 90 °C with the exposure time of 25-40 min.

Developmental hypothyroxinaemia induced by maternal mild iodine deficiency delays hippocampal axonal growth in the rat offspring

Iodine is essential for the biosynthesis of thyroid hormones, including triiodothyronine and thyroxine. Thyroid hormones are important for central nervous system development. Mild maternal iodine deficiency (ID)-induced hypothyroxinaemia causes neurological deficits and mental retardation of the foetus. However, the detailed mechanism underlying these deficits is still largely unknown. Given that the growth-associated protein of 43 kDa (GAP-43), semaphorin 3A (Sema3A) and the glycogen synthase kinase 3β (GSK3β)/collapsin response mediator protein 2 (CRMP2) pathway are essential for axonal development, we hypothesise that hippocampal axonal growth-related proteins may be impaired, which may contribute to hippocampal axonal growth delay in rat offspring exposed to maternal hypothyroxinaemia. To test this hypothesis, maternal hypothyroxinaemia models were established in Wistar rats using a mild ID diet. Besides a negative control group, two maternal hypothyroidism models were created with either a severe ID diet or methimazole in the water. Our results showed that maternal hypothyroxinaemia exposure delayed offspring axonal growth on gestational day 19, postnatal day (PN) 7, PN14 and PN21. Consistent with this, the mean intensity of hippocampal CRMP2 and Tau1 immunofluorescence axonal protein was reduced in the mild ID group. Moreover, maternal hypothyroxinaemia disrupted expressions of GAP-43 and Sema3A. Furthermore, the phosphorylation of GSK3β and CRMP2 was also affected in the treated offspring, implying a potential mechanism by which hypothyroxinaemia-exposure affects neurodevelopment. Taken together, our data support the hypothesis that maternal hypothyroxinaemia may impair axonal growth of the offspring.

The survival benefit of kidney transplantation in obese patients

Obese patients have a decreased risk of death on dialysis but an increased risk of death after transplantation, and may derive a lower survival benefit from transplantation. Using data from the United States between 1995 and 2007 and multivariate non-proportional hazards analyses we determined the relative risk of death in transplant recipients grouped by body mass index (BMI) compared to wait-listed candidates with the same BMI (n = 208 498). One year after transplantation the survival benefit of transplantation varied by BMI: Standard criteria donor transplantation was associated with a 48% reduction in the risk of death in patients with BMI ≥ 40 kg/m(2) but a ≥ 66% reduction in patients with BMI < 40 kg/m2. Living donor transplantation was associated with ≥ 66% reduction in the risk of death in all BMI groups. In sub-group analyses, transplantation from any donor source was associated with a survival benefit in obese patients ≥ 50 years, and diabetic patients, but a survival benefit was not demonstrated in Black patients with BMI ≥ 40 kg/m(2). Although most obese patients selected for transplantation derive a survival benefit, the benefit is lower when BMI is ≥ 40 kg/m(2), and uncertain in Black patients with BMI ≥ 40 kg/m(2).

Plasmon resonances and strong electric field enhancements in side-by-side tangent nanospheroid homodimers

The plasmon resonance and electric field enhancement in a side-by-side tangent nanospheroid homodimer (TNSHD) have been investigated theoretically by using DDA and FDTD methods, respectively. The simulation results indicate that this side-by-side TNSHD has its novel optical properties. We find that the plasmon resonance with a distinct Fano lineshape can be achieved and the electric field intensity can be enhanced strongly. The tunability of the Fano resonance could provide important applications in biosensing. The obtained electric field enhancement might open a promising pathway for surface-enhanced Raman scattering (SERS) and light trapping in solar cells.

Establishing best practices and guidance in population modeling: an experience with an internal population pharmacokinetic analysis guidance

This tutorial describes the development of a population pharmacokinetic (Pop PK) analysis guidance within Pfizer, which strives for improved consistency and efficiency, and a more systematic approach to model building. General recommendations from the Pfizer internal guidance and a suggested workflow for Pop PK model building are discussed. A description is also provided for mechanisms by which conflicting opinions were captured and resolved across the organization to arrive at the final guidance.

CPT: Pharmacometrics & Systems Pharmacology (2013) 2, e51; doi:10.1038/psp.2013.26; advance online publication 3 July 2013

Mechanisch induziertes Härten*

Seit dem Jahr 2001 wird an der Stiftung Institut für Werkstofftechnik Bremen (IWT) ein neues endwärmebehandlungsfreies Verfahren zur Herstellung von randschichtgehärteten Stahlbauteilen erforscht. Bei diesem Verfahren wird die Randschichthärtung durch eine mechanisch induzierte martensitische Phasenumwandlung in die Fertigungslinie integriert. Neben einer deutlichen Verkürzung der Produktionsdauer wird die lokale Härtung von Funktionsflächen eines Bauteils ermöglicht. Zudem kommt es durch die Einsparung einer abschlieβenden Wärmebehandlung zu einer signifikanten Reduzierung des Energieverbrauchs und der damit verbundenen CO2-Emission.

Um eine spannungs- bzw. dehnungsinduzierte martensitische Phasenumwandlung aufgrund von rein mechanischen Effekten zu ermöglichen, wird zunächst ein bei Raumtemperatur metastabiles austenitisches Gefüge hergestellt. Dieser Werkstoffzustand soll so stabil sein, dass eine spanende Bearbeitung keine ausgedehnte martensitische Phasenumwand-lung auslöst und das Werkstück somit noch “weich” bearbeitet werden kann. In einem anschlieβenden mechanischen Verfahren, wie z. B. einem Festwalzprozess, soll die auf die Werkstückoberfläche ausgeübte Pressung so weit gesteigert werden, dass die zur martensitischen Umwandlung des Austenits benötigte Spannung in der Bauteilrandzone erreicht wird.