Site-activated multifunctional chelator with acetylcholinesterase and neuroprotective-neurorestorative moieties for Alzheimer's therapy

A novel strategy to develop site-activated multifunctional chelators for targeting multiple etiologies of Alzheimer's disease is reported. The novel prochelator HLA20A with improved cytotoxicity shows little affinity for metal ions until it is activated by binding and inhibiting acetylcholinesterase (AChE), releasing an active chelator HLA20 that modulates amyloid precursor protein (APP) regulation and beta-amyloid (Abeta) reduction, suppresses oxidative stress, and passivates excess metal ions (Fe, Cu, and Zn) in the brain.

Magnetic correlations in the extended kagome YBaCo4O7 probed by single-crystal neutron scattering

We have studied the frustrated system YBaCo4O7.0 generally described as an alternating stacking of kagome and triangular layers of magnetic ions on a trigonal lattice, by single-crystal neutron diffraction experiments above the Néel ordering transition. Experimental data reveal pronounced magnetic diffuse scattering, which is successfully modeled by direct Monte Carlo simulations. Long-range magnetic correlations are found along the c axis, due to the presence of corner-sharing bipyramids, creating quasi-one-dimensional order at finite temperature. In contrast, in the kagome layers (ab plane), the spin-spin correlation function, displaying a short-range 120 degrees configuration, decays rapidly as typically found in spin liquids. YBaCo4O7 experimentally realizes a new class of two-dimensional frustrated systems where the strong out-of-plane coupling does not lift the in-plane degeneracy, but instead acts as an external "field."

Gamow-Teller strength distributions in 48Sc by the 48Ca(p,n) and 48Ti(n,p) reactions and two-neutrino double-beta decay nuclear matrix elements

The double-differential cross sections for the 48Ca(p,n) and 48Ti(n,p) reactions were measured at 300 MeV. A multipole decomposition technique was applied to the spectra to extract the Gamow-Teller (GT) components. The integrated GT strengths up to an excitation energy of 30 MeV in 48Sc are 15.3+/-2.2 and 2.8+/-0.3 in the (p,n) and (n,p) spectra, respectively. In the (n,p) spectra additional GT strengths were found above 8 MeV where shell models within the fp shell-model space predict almost no GT strengths, suggesting that the present shell-model description of the nuclear matrix element of the two-neutrino double-beta decay is incomplete.

Testosterone, sex hormone-binding globulin and free androgen index among adult women: chronological and ovarian aging

BACKGROUND

In this study, levels and rates of change in total testosterone (T), sex hormone-binding globulin (SHBG) and free androgen index (FAI) were related to chronological age and to the final menstrual period (FMP) as an indicator of ovarian aging.

METHODS

Data were annually acquired over a 15-year period in 629 women of the Michigan Bone Health and Metabolism Study cohort. Data were censored for hormone therapy use. Endogenous androgen patterns over time were described with stochastic processes and bootstrapping.

RESULTS

With ovarian aging, T levels rose from a mean of 18 ng/dl commencing 10 years prior to the FMP to 27 ng/dl at the FMP. Over the 20-year period encompassing the FMP, modeled mean SHBG levels changed from 58 to 34 nM and the FAI ratio increased from 1.6 to 2.9 in a non-linear manner. With chronological aging, total T levels increased (P < 0.0001) from 43 to 50 years, but not thereafter. SHBG declined steadily with age with a modestly greater rate of change between 49 and 54 years. The FAI increased from 1.3 to 2.5 from 34 to 58 years.

CONCLUSIONS

T increased from approximately age 40 until the FMP whereas SHBG had rate of change patterns reflecting both chronological and ovarian aging components. These data provide new insight into the endogenous androgen patterns at mid-life.

Phase II study of darinaparsin in patients with advanced hepatocellular carcinoma

e15630

Background: Inorganic arsenic has reported activity in advanced hepatocellular carcinoma (HCC) in Asia, yet its efficacy is limited by liver toxicity. Darinaparsin is a novel organic arsenic that is capable of reaching higher intracellular concentration in cells with decreased toxicity compared to inorganic arsenic. It is highly active as a single agent in HCC cell lines and animal tumor models. We conducted a multi-center phase II study with darinaparsin in patients with advanced HCC. Methods: Eligibility criteria included unresectable or metastatic measurable HCC, up to two prior systemic treatments, ECOG performance status ≤2, Child Pugh Class A or B and adequate organ functions. Darinaparsin was given at 420 mg/m2 intravenously administered over 60 minutes through a central line, twice weekly at least 72 hours apart for three weeks followed by one-week rest in a four-week cycle. The primary end point of the study was response rate. A Simon two-stage design was used to assess the efficacy of darinaparsin and the study would be terminated if no responses were observed after the first stage. Results: The planned 15 patients of the first stage were enrolled: median age = 60 (35 - 79). M/F = 14/1, ECOG performance status 0/1= 4/11, Child Pugh class A/B = 11/4. Seven patients received prior systemic chemotherapies. No objective responses were observed. Three patients had stable disease. The median number of cycles on study per patient was 2 (1–6). The median progression free survival and overall survival were 55 days (95% confidence interval: 50 - 59) and 190 days (95% confidence interval: 93–227), respectively. Treatment was well tolerated. No treatment related hospitalizations or deaths occurred. Treatment related grade 1–2 toxicities included nausea/vomiting (31%), fatigue (23%), anorexia (15%) and diarrhea (15%). Grade 3 anorexia, wheezing, agitation, right upper quadrant pain and SGPT were observed in 1 patient each (8%), 1 patient experienced grade 4 hypoglycemia (8%). Conclusions: Darinaparsin was safely administered with tolerable toxicity profiles in HCC patients. However, it has shown no objective responses in HCC and this trial was terminated as planned after the first stage of efficacy analysis.

[Table: see text]

Mitogenic effect contributes to increased virulence of Streptococcus suis sequence type 7 to cause streptococcal toxic shock-like syndrome

Streptococcus suis serotype 2 sequence type 7 strains emerged in 1996 and caused a streptococcal toxic shock-like syndrome in 1998 and 2005 in China. Evidence indicated that the virulence of S. suis sequence type 7 had increased, but the mechanism was unknown. The sequence type 7 strain SC84, isolated from a patient with streptococcal toxic shock-like syndrome during the Sichuan outbreak, and the sequence type 1 strain 31533, a typical highly pathogenic strain isolated from a diseased pig, were used in comparative studies. In this study we show the mechanisms underlying cytokine production differed between the two types of strains. The S. suis sequence type 7 strain SC84 possesses a stronger capacity to stimulate T cells, naive T cells and peripheral blood mononuclear cell proliferation than does S. suis sequence type 1 strain 31533. The T cell response to both strains was dependent upon the presence of antigen-presenting cells. Histo-incompatible antigen-presenting cells were sufficient to provide the accessory signals to naive T cell stimulated by the two strains, indicating that both sequence type 7 and 1 strains possess mitogens; however, the mitogenic effect was different. Therefore, we propose that the difference in the mitogenic effect of sequence type 7 strain SC84 compared with the sequence type 1 strain 31533 of S. suis may be associated with the clinical, epidemiological and microbiological difference, where the ST 7 strains have a larger mitogenic effect.

Local structure of La1-xSrxCoO3 determined from EXAFS and neutron pair distribution function studies

The combined local structure techniques, extended x-ray absorption fine structure and neutron pair distribution function analysis, have been used for temperatures 4< or =T< or =330 K to rule out a large Jahn-Teller (JT) distortion of the Co-O bond in La1-xSrxCoO3 for a significant fraction of Co sites (x< or =0.35), indicating few, if any, JT-active, singly occupied e_{g} Co sites exist.

Pten and p53 converge on c-Myc to control differentiation, self-renewal, and transformation of normal and neoplastic stem cells in glioblastoma

Glioblastoma (GBM) is a highly lethal primary brain cancer with hallmark features of diffuse invasion, intense apoptosis resistance and florid necrosis, robust angiogenesis, and an immature profile with developmental plasticity. In the course of assessing the developmental consequences of central nervous system (CNS)-specific deletion of p53 and Pten, we observed a penetrant acute-onset malignant glioma phenotype with striking clinical, pathological, and molecular resemblance to primary GBM in humans. This primary, as opposed to secondary, GBM presentation in the mouse prompted genetic analysis of human primary GBM samples that revealed combined p53 and Pten mutations as the most common tumor suppressor defects in primary GBM. On the mechanistic level, the "multiforme" histopathological presentation and immature differentiation marker profile of the murine tumors motivated transcriptomic promoter-binding element and functional studies of neural stem cells (NSCs), which revealed that dual, but not singular, inactivation of p53 and Pten promotes cellular c-Myc activation. This increased c-Myc activity is associated not only with impaired differentiation, enhanced self-renewal capacity of NSCs, and tumor-initiating cells (TICs), but also with maintenance of TIC tumorigenic potential. Together, these murine studies have provided a highly faithful model of primary GBM, revealed a common tumor suppressor mutational pattern in human disease, and established c-Myc as a key component of p53 and Pten cooperative actions in the regulation of normal and malignant stem/progenitor cell differentiation, self-renewal, and tumorigenic potential.

Krupple-like factor 5 promotes breast cancer proliferation through activating fibroblast growth factor-binding protein transcription

Abstract #4071

Breast cancer is the second leading cause of cancer death in U.S. women. The estrogen receptor negative basal breast cancer is usually invasive and the prognosis is poor. Kruppel-like Factor 5 (KLF5) is a zinc-finger transcription factor promoting cell proliferation, survival, cell cycle, and angiogenesis. High expression level of KLF5 has been shown to be associated with shorter breast cancer patient survival time. In our previous microarray studies, fibroblast growth factor binding protein (FGF-BP) is suggested to be one of the KLF5's downstream target genes in the TSU-Pr1 bladder cancer cell line. FGF-BP has been appreciated to be overexpressed in breast tumors and promotes tumorigenesis. To test whether KLF5 promotes cell proliferation through inducing FGF-BP gene transcription in breast cells, we first examined the KLF5 and FGF-BP protein levels in a panel of breast cell lines and found that KLF5 and FGF-BP are co-expressed in ER-negative basal breast cell lines. Over-expression of KLF5 by adenovirus dramatically increased the FGF-BP mRNA and protein expression in MCF7 and BT474. In contrast, KLF5 knockdown decreased the FGF-BP mRNA and protein expression in HCC1937, BT20, and SW527. Importantly, we found that FGF-BP, like KLF5, promotes cell proliferation in MCF10A, SW527 and TSU-Pr1 cells by H3-thymidine incorporation assay. Furthermore, we demonstrated that KLF5 activates the FGF-BP promoter through a putative KLF5 binding site by luciferase reporter assays. We further showed that KLF5 binds to the FGF-BP promoter in vitro by oligo pull down assays and in vivo by chromatin immunoprecipetation (CHIP) assays. These findings suggest that KLF5 may promote breast cancer cell proliferation through directly activating the FGF-BP mRNA transcription. This study will yield valuable insights into the mechanism of KLF5 induced cancer pathogenesis, and will result in useful diagnostic and therapeutic targets.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4071.

Differentiation of sarcoidosis from tuberculosis using real-time PCR assay for the detection and quantification of Mycobacterium tuberculosis

BACKGROUND

The clinical and pathological features of sarcoidosis and tuberculosis may mimic each other, and when the caseous necrosis is not seen in tuberculosis tissue, differentiation is not easy.

OBJECTIVE

This study evaluates the ability of real-time PCR quantification and sets the quantitive value to differentiate sarcoidosis from TB.

METHODS

Formalin-fixed and paraffin-embedded sections of biopsy samples, from 104 patients with sarcoidosis, 31 patients with tuberculosis, and 55 controls with other respiratory diseases (26 with nonspecific lymphadenitis and 29 with emphysema bullae), were collected to amplify insertion sequence IS986 of Mycobacterium tuberculosis (MTB) genome by real-time quantitative PCR. The diagnostic performance of qualitative and quantitative analysis of real-time quantitative PCR was assessed by receiver-operating characteristic (ROC) curves.

RESULTS

MTB DNA was detected in 20 of the 104 sarcoidosis samples and 7 of the 55 control samples, but was detected in all of the 31 tuberculosis samples. The numbers of MTB genomes were 0-4.71x10(3) copies per ml in sarcoidosis samples, 1.58x10(2)-5.43x10(7) copies per ml in tuberculosis samples and 0-1.02x10(3) copies per ml in controls with quantitative analysis. Receiver-operating characteristic (ROC) curves showed that MTB genome quantification had greater diagnostic performance than MTB genome qualitation in discriminating patients with sarcoidosis from those with tuberculosis (area under the ROC curves: 0.994 vs 0.904, P<0.001). The sensitivity and specificity of qualitative analysis were 100% and 80.8% respectively. At cutoff value of 1.14x10(3) copies per ml for MTB genome quantification, the sensitivity was 96.8% and specificity was 98.1%.

CONCLUSIONS

The real time PCR quantification is a valuable test for differentiation between sarcoidosis and tuberculosis, and the MTB genome copies number of 1.14x10(3) copies per ml should be preferred as quantitative cutoff value for the differentiation.

Quantum Zeno and anti-Zeno effects: without the rotating-wave approximation

We show that the counterrotating, neglected in the previous studies of the quantum Zeno effect (QZE) in atomic decay, can have a large impact on the short-time evolution. We calculate the electron self-energy, the Lamb shift, and the QZE without making the rotating-wave approximation (RWA) and show that, for hydrogen in free space, the Zeno time is longer by 2 orders of magnitude than that obtained from the RWA. We also show that there is no anti-Zeno effect as the counterrotating terms and rotating terms represent the opposite processes in the higher frequency region. Consequently, the experimental measurement of the QZE may be much easier than what was determined with the RWA results.

Effects of functional electrical stimulation relating to leg movement

Functional electrical stimulation (FES) has grown to be an effective and important element in the biomedical industry over the years. Due to this fact, it has become the basis of many researches. However, much work is focused on the theory and control technique with very few relating experiments. In this work, some key experiments were performed on the leg muscles during the leg movement. Some useful results were obtained with regards to muscle reaction, in terms EMG readings. The stimulus of the FES system was also applied to the muscles during the leg movement. The readings of experiments reveal some important muscle properties which are verified accordingly.