UTILIZATION OF TWO-DIMENSIONAL FAST FOURIER TRANSFORM AND POWER SPECTRAL ANALYSIS FOR ASSESSMENT OF EARLY DEGENERATION OF ARTICULAR CARTILAGE

Degeneration of articular cartilage begins from deterioration of the collagen fibres in the superficial zone. Standard histology using 2D imaging technique is often used to determine the microstructure of collagen fibres and the physiological functions of articular cartilage. However, information of the 3D collageneous structure in the cartilage could be lost and misinterpreted in 2D observations. In contrast, confocal microscopy permits studying the 3D internal structure of bulk articular cartilage with minimal physical disturbing. Using fibre optic laser scanning confocal microscopy, a 3D histology has been previously developed to visualize the collagen matrix in the superficial zone by means of identifying the early arthritic changes in articular cartilage. In this study, we characterized the collagen orientation in the superficial zone of normal cartilage, the cartilage with surface disruption and fibrillated cartilage using Fast Fourier transforms and power spectral analysis techniques. Thus, we have established an objective method for assessing the early pathology changes in the articular cartilage.

Percutaneous vertebroplasty for pain management in spinal metastasis with epidural involvement

Percutaneous vertebroplasty (PVP) has been widely used for the treatment of painful malignant lesions of the spine. Spinal metastasis with epidural involvement, with or without symptoms of neurologic compression, is regarded by some authors as a contraindication or relative contraindication to the procedure. To evaluate safety and effectiveness of PVP in pain management of spinal metastasis with epidural involvement, we retrospectively analyzed PVP in 32 patients with metastatic disease, who presented with at least one vertebral lesion with destruction of the posterior vertebral body wall or epidural extension of tumor. Among these patients, nine had signs of spinal cord or cauda equina compression. Procedural safety was evaluated by any post-procedure adverse events. The PVP analgesic efficacy was evaluated by follow-up neurological examination. Pain intensity was scored on a visual analog scale scored from 0 (no pain) to 10 (maximum pain intensity). The effective pain relief was defined as at least 50% improvement in pain score as compared with pre- procedure baseline. Follow-up assessments were performed at 1 day; 1 week; 1, 3, and 6 months after the procedure. Fifty-three vertebrae in 32 patients were treated in this group. Analgesic efficacy in survival patients was rated at 97% (31/32) at 1day and 1 week, 86.7% (26/30) at 1 month, 82.3% (24/29) at 3 months, and 76.9% (20/26) at 6 months after procedure. Leakage of PMMA was detected in 64% (33/53) treated vertebrae. No systemic complications were observed in all treated patients.

Sequence variation and genetic diversity in the giant panda

About 336-444 bp mitochondrial D-loop region and tRNA gene were sequenced for 40 individuals of the giant panda which were collected from Mabian, Meigu, Yuexi, Baoxing, Pingwu, Qingchuan, Nanping and Baishuijiang, respectively. 9 haplotypes were found in 21 founders. The results showed that the giant panda has low genetic variations, and that there is no notable genetic isolation among geographical populations. The ancestor of the living giant panda population perhaps appeared in the late Pleistocene, and unfortunately, might have suffered bottleneck attacks. Afterwards, its genetic diversity seemed to recover to some extent.

Sulfur passivation and contact methods for GaAs nanowire solar cells

The effect of sulfur passivation on core-shell p-n junction GaAs nanowire (NW) solar cells has been investigated. Devices of two types were investigated, consisting of indium tin oxide contact dots or opaque Au finger electrodes. Lateral carrier transport from the NWs to the contact fingers was achieved via a p-doped GaAs surface conduction layer. NWs between the opaque contact fingers had sidewall surfaces exposed for passivation by sulfur. The relative cell efficiency increased by 19% upon passivation. The contribution of the thin film grown between the NWs to the total cell efficiency was estimated by removing the NWs using a sonication procedure. Mechanisms of carrier transport and photovoltaic effects are discussed on the basis of spatially resolved laser scanning measurements.

Immunohistochemical analysis of structural changes in collagen for the assessment of osteoarthritis

Collagen fibrillation within articular cartilage (AC) plays a key role in joint osteoarthritis (OA) progression and, therefore, studying collagen synthesis changes could be an indicator for use in the assessment of OA. Various staining techniques have been developed and used to determine the collagen network transformation under microscopy. However, because collagen and proteoglycan coexist and have the same index of refraction, conventional methods for specific visualization of collagen tissue is difficult. This study aimed to develop an advanced staining technique to distinguish collagen from proteoglycan and to determine its evolution in relation to OA progression using optical and laser scanning confocal microscopy (LSCM). A number of AC samples were obtained from sheep joints, including both healthy and abnormal joints with OA grades 1 to 3. The samples were stained using two different trichrome methods and immunohistochemistry (IHC) to stain both colourimetrically and with fluorescence. Using optical microscopy and LSCM, the present authors demonstrated that the IHC technique stains collagens only, allowing the collagen network to be separated and directly investigated. Fluorescently-stained IHC samples were also subjected to LSCM to obtain three-dimensional images of the collagen fibres. Changes in the collagen fibres were then correlated with the grade of OA in tissue. This study is the first to successfully utilize the IHC staining technique in conjunction with laser scanning confocal microscopy. This is a valuable tool for assessing changes to articular cartilage in OA.

Variable expression of the Fragile X Mental Retardation 1 (FMR1) gene in patients with premature ovarian failure syndrome is not dependent on number of (CGG)n triplets in exon 1

BACKGROUND

Increased expression of the Fragile X Mental Retardation 1 (FMR1) gene in blood cells has been claimed to be associated with variable (CGG)(n) triplet numbers in the 5' untranslated region of this gene. Increased CGG triplet numbers, including that of the so-called premutation range (n= 55-200), were shown to have a risk of <26% to impair ovarian reserve leading to primary ovarian insufficiency and premature ovarian failure (POF).

METHODS

DNA and RNA samples were isolated from 74 patients with idiopathic POF to evaluate quantitatively the expression of FMR1 in leukocytes and CGG triplet number on FMR1 gene alleles. mRNA levels were normalized and compared with those of control women. Expression of the encoded protein (FMRP) was analysed by immunohistochemistry on ovarian biopsy tissue sections.

RESULTS

A large variance of the FMR1 transcript level was found in the leukocyte RNA samples, but only in patients with POF, and this variability did not correlate to variance of CGG triplet numbers found on both FMR1 alleles (19 < n > 90). During normal folliculogenesis, FMRP is predominantly expressed in granulosa cells.

CONCLUSIONS

Our data suggest that FMR1 expression during human folliculogenesis is probably a quantitative trait. Proper function of FMRP in granulosa cells seems to depend on an optimal transcript level. All women with CGG triplet numbers outside the range associated with normal folliculogenesis (26 < n > 34) are therefore expected to have a relaxed FMR1 transcription control. FMR1 transcript levels in leukocytes might therefore be diagnostic for altered FMRP levels in granulosa cells, which will affect the process of folliculogenesis.

Exploring the role of phase modulation on photoluminescence yield

We report an investigation to elucidate the mechanisms of control in phase-sensitive experiments in two molecular systems. A first inspection of optimization procedures yields the same experimental result: increase in the emission efficiency upon excitation by a phase modulated pulse in a two-photon transition. More detailed studies, which include power dependence, spectral response, one and two color pump-probe and pump-pump experiments show that while for one chromophore phase modulation leads to spectral matching between the two-photon cross section and the second order power spectrum for the other it provides a tool to manipulate the wavepacket dynamics in the excited state.

Human papillomavirus is detectable in Barrett's esophagus and esophageal carcinoma but is unlikely to be of any etiologic significance

Barrett's esophagus (BE), a known precursor of esophageal adenocarcinoma has recently been associated with human papillomavirus (HPV). p16(INK4a) expression is a recognized surrogate marker of HPV infection in the cervix.

OBJECTIVES

This study has assessed the possible role of human papillomavirus (HPV) infection in BE and esophageal adenocarcinoma, in the North American population by screening esophageal tissues for HPV by a combination of assays.

STUDY DESIGN

Formalin-fixed, paraffin-embedded blocks from cases of Barrett's esophagus (n=84), esophageal adenocarcinoma (n=36) and normal gastro-esophageal junction (n=29) were examined for HPV by PCR, chromogenic in situ hybridization, and p16(INK4a) immunohistochemistry.

RESULTS

HPV DNA was detected by PCR in 23 of 84 (27.4%) BE cases, 11 of 36 (31%) cases of adenocarcinoma and in 7 of 29 (24%) normal control cases (p=0.82). p16(INK4a) staining was positive in 10 (12%) cases of BE, 15 (42%) cases of adenocarcinoma and 6 (21%) cases of the control group. Positive p16(INK4a) staining was not statistically different between the three groups whether positive or negative for HPV DNA (p=0.91 and p=0.91 respectively). Similarly, negative p16(INK4a) staining did not show a difference between the three groups for whether positive or negative for HPV DNA (p=0.50 and p=0.28, respectively). HPV was not detected by CISH in the adenocarcinomas while in BE and control groups, CISH was non-contributory.

CONCLUSIONS

These data suggest that while HPV is detectable in a subset of esophageal lesions and tumors, the HPV detected is unlikely to be of etiologic significance or a factor accounting for the increase in BE and esophageal adenocarcinoma cases in the United States.

Abstract P6-15-20: Development of PEA-15-Based Therapy in Breast Cancer in a Preclinical Study

Background: PEA-15 (phosphoprotein enriched in astrocytes, 15 kDa) has tumor suppressor properties in both breast and ovarian cancer cells. Overexpression of PEA-15 in MDA-MB-468 triple-negative breast cancer cells using adenoviral vector (Ad.PEA-15) inhibited cell growth by inducing apoptosis. Treatment with Ad.PEA-15 led to significant regression of tumors in mice, indicating that PEA-15 could have therapeutic potential in breast cancer. PEA-15 exerts its antitumor activity by binding to ERK in the cytoplasm and preventing its translocation into the nucleus, thereby inhibiting ERK-dependent transcription and cell proliferation. Because ERK inhibitors have been shown to be toxic, in this study, we developed PEA-15 mimetic peptides as a therapeutic agent in breast cancer. These peptides, which are expected to be less toxic because of their ability to mimic PEA-15, are proposed to inhibit cell proliferation by sequestering ERK in the cytoplasm.

Material and Methods: PEA-15 mimetic peptides were designed and synthesized based on structural analysis of linear segments from the C-terminal end of PEA-15, which is one of the two regions that are presumably critical for ERK binding, using nuclear magnetic resonance spectroscopy. These synthetic peptides were labeled with FAM to enable determination of their subcellular localization. The PULSin reagent was used as a delivery reagent for peptide penetration into cancer cells. The penetration ability of these peptides into HeLa and MDA-MB-468 cells was analyzed by fluorescence microscope and fluorescence-activated cell sorting. Their effect on ERK subcellular localization was examined by cell-fractionation analysis. Their impact on cell survival was determined by trypan blue viability assay and propidium iodide staining. Results: Ten peptides were designed and synthesized based on the C-terminal segments of PEA-15. Three of these FAM-labeled synthetic peptides delivered with the PULSin reagent were able to penetrate HeLa and MDA-MB-468 cells with 80-90% and 30-40% efficiency, respectively. Further, these peptides redirected ERK into the cytoplasm from the nucleus in MDA-MB-468 cells and caused 31% reduction in viability of HeLa cells as compared to the untreated control. Ongoing studies are evaluating PEA-15 peptides for their ability to interact with ERK using ELISA. In the future, we will also test their therapeutic efficacy and safety using a xenograft breast cancer model.

Discussion: Previous studies revealed that PEA-15 has antitumor activity against breast and ovarian cancer cells by sequestering ERK in the cytoplasm. Due to the toxicity of ERK enzymatic inhibitors, we developed PEA-15 mimetic peptides and demonstrated their therapeutic potential for breast cancer, which may provide opportunities for breast cancer patients who currently have limited treatment options.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-15-20.

Chromium improves protein deposition through regulating the mRNA levels of IGF-1, IGF-1R, and Ub in rat skeletal muscle cells

The aim of this study was to evaluate the impact of three different chromium forms--chromic chloride (CrCl3), chromium picolinate (CrPic), and a newly synthesized complex of chromium chelated with small peptides (CrSP)--on protein metabolism in vitro. In cultured skeletal muscle cells, CrSP was able to increase the basal and insulin-stimulated levels of protein deposition in skeletal muscles cells. CrCl3 and CrPic augmented insulin-stimulated protein synthesis. At the molecular level, insulin significantly increased the mRNA levels of insulin-like growth factor 1 and insulin-like growth factor 1 receptor. These impacts could be enhanced by the addition of chromium, especially CrSP. The mRNA levels of ubiquitin were significantly reduced when cells were cultured with chromium or/and insulin. Assuming that the mRNA level increase or decrease results in increased or decreased levels of these proteins, chromium would improve protein anabolism and reduce protein catabolism and then prove protein deposition in rat skeletal muscle cells.

The association between internet addiction and self-injurious behaviour among adolescents

OBJECTIVE

To examine the association between internet addiction and self-injurious behaviour (SIB) in adolescence.

METHODS

Population-based cross-sectional survey of 1618 high school students aged 13-18 years in Guangzhou city, Guangdong Province, PR China. Deliberate SIB was measured using self-reported questionnaire; internet addiction was assessed using the Internet Addiction Test (IAT).

RESULTS

263 (16.3%) participants reported having committed some form of SIB in the past 6 months. 73 (4.5%) had committed SIB 6 times or more, and 157 (9.7%) 1-5 times. The majority of respondents were classified as normal users of the internet (n = 1392, 89.2%), with 158 (10.2%) moderately and 10 (0.6%) severely addicted to the internet. After adjusting for potential confounders, the odds ratio for SIB was 2.0 (95% CI 1.1 to 3.7) for those who were classified as moderately and severely addicted to the internet when compared to the normal group.

CONCLUSIONS

SIB is common in adolescence in the study population in China. Addiction to the internet is detrimental to mental health and increases the risk of self-injury among adolescents. Clinicians need to be aware of potential co-morbidities of other addictions among adolescent self-injured patients.

HPV DNA is associated with a subset of Schneiderian papillomas but does not correlate with p16(INK4a) immunoreactivity

This study investigated the role of human papillomavirus (HPV) in Schneiderian papillomas (SPs) to determine whether HPV is associated with the pathogenesis of particular histologic subtypes and whether p16(INK4a) can be used as a surrogate marker for HPV detection. Twenty-seven papilloma specimens (19 inverted [IPs], 6 exophytic [EPs], 1 oncocytic [OP] and 1 mixed) were collected from 23 patients. Purified SP DNA extracts were tested for HPV by PCR using GP5 +/GP6 + primers; HPV genotyping was performed by dot blot hybridization. PCR positive specimens were screened for HPV by biotinyl-tyramide-based chromogenic in situ hybridization (CISH). Immunohistochemsistry (IHC) for the HPV L1 capsid protein and for p16(INK4a) was performed on all specimens. HPV was detected by PCR in 16/27 (59.3%) SPs; 9/19 (47.4%) IPs; 6/6 (100%) EPs [p = 0.051], and 1/1 (100%) mixed SP. HPV was not detected in the single OP. High risk genotypes were detected in 4/9 IPs (44.4%) and 0/6 EPs (0%) [p = 0.10]. Seven of 16 PCR positive SPs were also CISH positive for HPV: 5/6 EPs (83.3%) and 1/9 IP (11.1%) [p = 0.01]. IHC for the L1 capsid protein was positive in 2 SPs (1 EP and 1 mixed). p16(INK4a) staining was seen in 14/16 (87.5%) PCR positive SPs and in 10/11 (90.9%) PCR negative SPs (p = 1.00). In summary, this study demonstrates a strong association between HPV and EPs, however, its role in IPs remains less well-defined. Further, p16(INK4a) is not a useful surrogate marker for HPV detection across the various SPs.

Identification of brassinosteroid responsive genes in Arabidopsis by cDNA array

We have systematically monitored brassinosteroid (BR) responsive genes in a BR-deficient mutant det2 suspension culture of Arabidopsis by using a cDNA array approach. Among 13000 cDNA clones arrayed on filters, 53 BR responsive clones were identified and designated BRR1-BRR53. Sequence analysis of 43 clones showed that 19 clones are novel genes, 3 clones are genes involved in the control of cell division, 4 clones are genes related to plant stress responses, 4 clones are transcriptional factor or signal transduction component genes, and 3 clones are genes involved in RNA splicing or structure forming. In addition, we also found that BR regulated the transcription of genes related to many physiological processes, such as photoreaction, ion transportation and some metabolic processes. These findings present molecular evidence that BR plays an essential role in plant growth and development.

Chromium improves glucose uptake and metabolism through upregulating the mRNA levels of IR, GLUT4, GS, and UCP3 in skeletal muscle cells

The aim of this study was to evaluate the impact of three different chromium forms as chromic chloride (CrCl), chromium picolinate (CrPic), and a newly synthesized complex of chromium chelated with small peptides (CrSP) on glucose uptake and metabolism in vitro. In cultured skeletal muscle cells, chromium augmented insulin-stimulated glucose uptake and metabolism as assessed by a reduced glucose concentration of culture medium. At the molecular level, insulin significantly increased the mRNA levels of insulin receptor (IR), glucose transporter 4 (GLUT4), glycogen synthase (GS), and uncoupling protein-3 (UCP3), and these impacts can be enhanced by the addition of chromium, especially in the form of CrSP. Collectively, results of this study demonstrate that chromium improves glucose uptake and metabolism through upregulating the mRNA levels of IR, GLUT4, GS, and UCP3 in skeletal muscle cells, and CrSP has higher efficacy on glucose uptake and metabolism compared to the forms of CrCl and CrPic.

Computer-aided detection (CAD) and assessment of malignant lesions in the liver and lung using a novel PET/CT software tool: initial results

PURPOSE

To determine the feasibility of a PET/CT software tool (PET computer-aided detection: PET-CAD) for automated detection and assessment of pulmonary and hepatic lesions.

MATERIALS AND METHODS

20 consecutive patients with colorectal liver metastases and 20 consecutive patients suffering from non-small cell lung cancer (NSCLC) were examined with FDG-PET/CT. In a first step the maximum standardized uptake values (SUV (max)) of non-tumorous liver and lung tissues were determined manually. This value was used as a threshold value for software-based lesion detection. The number of lesions detected, their SUV (max), and their sizes in the x, y, and z-planes, as automatically provided by PET-CAD, were compared to visual lesion detection and manual measurements on CT.

RESULTS

The sensitivity for automated detection was 96 % (86 - 99 %) for colorectal liver metastases and 90 % (70 - 99 %) for lung lesions. The positive predictive value was 80 % for liver and 68 % for lung lesions. The mean SUV (max) of all lung lesions was 9.3 and 8.8 for the liver lesions. When assessed by PET-CAD, the mean lesion sizes for liver lesions in the x, y, and z-planes were 4.3 cm, 4.6 cm, and 4.2 cm compared to 3.5 cm, 3.8 cm, and 3.6 cm for manual measurements. The mean lesion sizes of lung lesions were 7.4 cm, 7.7 cm, and 8.4 cm in the x, y, and z-planes when assessed by PET-CAD compared to 5.8 cm, 6.1 cm, and 7.1 cm when measured manually. Using manual assessment, the lesion sizes were significantly smaller in all planes (p < 0.005).

CONCLUSION

Software tools for automated lesion detection and assessment are expected to improve the clinical PET/CT workflow. Before implementation in the clinical routine, further improvements to the measurement accuracy are required.