Heavy-chain antibody targeting of CD38 NAD+ hydrolase ectoenzyme to prevent fibrosis in multiple organs

The functionally pleiotropic ectoenzyme CD38 is a glycohydrolase widely expressed on immune and non-hematopoietic cells. By converting NAD+ to ADP-ribose and nicotinamide, CD38 governs organismal NAD+ homeostasis and the activity of NAD+-dependent cellular enzymes. CD38 has emerged as a major driver of age-related NAD+ decline underlying adverse metabolic states, frailty and reduced health span. CD38 is upregulated in systemic sclerosis (SSc), a chronic disease characterized by fibrosis in multiple organs. We sought to test the hypothesis that inhibition of the CD38 ecto-enzymatic activity using a heavy-chain monoclonal antibody Ab68 will, via augmenting organismal NAD+, prevent fibrosis in a mouse model of SSc characterized by NAD+ depletion. Here we show that treatment of mice with a non-cytotoxic heavy-chain antibody that selectively inhibits CD38 ectoenzyme resulted in NAD+ boosting that was associated with significant protection from fibrosis in multiple organs. These findings suggest that targeted inhibition of CD38 ecto-enzymatic activity could be a potential pharmacological approach for SSc fibrosis treatment.

DDEL-13. ULTRASOUND-ENHANCED DELIVERY OF LIPOSOMAL DOXORUBICIN ACROSS THE BLOOD BRAIN BARRIER INDUCES AN IFN-GPHENOTYPE IN MICROGLIA, MACROPHAGES, AND T CELLS AND IMPROVES RESPONSE TO PD-1 BLOCKADE IN GLIOMAS

INTRODUCTION

Given the limited drug penetration across the blood-brain barrier (BBB), the therapeutic potential of new and existing therapies has not been fully exploited for the benefit of glioblastoma (GBM) patients.

METHODS

Here we employed a novel drug delivery technology based on low-intensity pulsed ultrasound combined with intravenous microbubbles (LIPU/MB) that temporarily opens the BBB to deliver liposomal doxorubicin (DOX) and anti-PD-1 therapy (aPD-1) in mouse glioma models and 3 recurrent GBM patients. Immunological variables were evaluated in tumor and immune cells as well as efficacy in glioma-bearing mice treated with DOX delivered by LIPU. These included measurement of HLA ABC and HLA DR protein expression by tumor cells, microglia, and macrophages and IFN-g production by glioma-associated microglia and macrophages in mouse and human tumors. We also assessed efficacy of LIPU/MB enhanced combination therapy in glioma-bearing mice.

RESULTS

Upregulation of HLA ABC and HLA DR was observed in GBM cell lines at low concentrations of DOX. Tumor cells from GBM patients treated with DOX, aPD-1 and LIPU/MB showed increased expression of HLA ABC and HLA DR compared to paired pretreatment samples. In both mice and humans, LIPU/MB liposomal DOX increased absolute brain drug concentrations and elicited a specific IFN-g phenotype and MHC I expression in glioma-associated microglia and macrophages in mice and humans. Furthermore, LIPU/MB-mediated BBB opening increased brain concentrations of aPD-1 in mice and in peritumoral regions of GBM patients. Combined treatment with liposomal DOX and aPD-1 delivered with LIPU/MB resulted in long-term survival of glioma-bearing mice that relied on the activity of CD8+ T cells for its efficacy.

CONCLUSIONS

Overall, this translational study demonstrates the utility of LIPU/MB to stimulate intracranial immune responses in the context of treatment with DOX and aPD-1 for gliomas.

Improvement of Performance for Raman Assisted BOTDR by Analyzing Brillouin Gain Spectrum

We propose a simplified partitioned Brillouin gain spectrum (BGS) analysis method to enhance the spatial resolution and measurement accuracy of a Brillouin optical time-domain reflectometer (BOTDR) assisted by a first-order Raman pump. We theoretically derive the mathematical model of the partitioned BGS and analyze the superposition process of sub-Brillouin signals within a theoretical spatial resolution range. We unified all the unknown constant parameters of the calculation process to simplify the partitioned BGS analysis method and the value of the uniform parameter is attained through the system test data and numerical analysis. Moreover, to automate data processing, the starting point of the temperature/strain change is determined by the first occurrence of the maximum Brillouin frequency shift (BFS), then the position where the partitioned BGS analysis method calculation begins is obtained. Using a 100 ns probe pulse and partitioned BGS analysis method, we obtain a spatial resolution of 0.4 m in the 78.45-km-long Raman-assisted BOTDR system, and the measurement accuracy is significantly improved. In addition, we achieve a strain accuracy of 5.6 με and a spatial resolution of 0.4 m in the 28.5-km-long BOTDR without Raman amplification.

Ureteroscopic holmium laser to transect the greater omentum to remove an abdominal drain: Four case reports

BACKGROUND

Drainage tube removal is difficult when the greater omentum becomes incarcerated in the drainage tube through the side holes. Currently, known removal methods are either ineffective or will cause additional damage to the patient in a secondary operation. Ureteroscopy and the holmium laser have been used in various surgical techniques in urology, and in theory, they are expected to be a good strategy for solving the problem of tissue incarceration.

CASE SUMMARY

Four patients diagnosed with difficult removal of an abdominal drainage tube following abdominal surgery are reported. All patients underwent surgery to remove the incarcerated greater omentum in the drainage tube using a holmium laser and a ureteroscope, and a new 16-F drain was then placed in the abdominal or pelvic cavity. The efficacy of this technique was evaluated by intraoperative conditions, success rate, and operating time; safety was evaluated by perioperative conditions and the probability of postoperative complications. All four operations went smoothly, and the drains were successfully removed in all patients. The average operating time was 24.5 min. Intraoperatively, the average irrigation volume was 892.0 mL, the average drainage volume was 638.5 mL, and no bleeding or damage to surrounding tissues was observed. Postoperatively, the average drainage volume was 32.8 mL and the new drains were removed within 36 h. All patients were able to get out of bed and move around within 12 h. Their visual analogue pain scores were all below 3. The average follow-up duration was 12.5 mo and no complications such as fever or bleeding were noted.

CONCLUSION

Ureteroscopic holmium laser surgery is an effective, safe and minimally invasive technique for removing drains where the greater omentum is incarcerated in the abdominal drain.

Targeting CD38-dependent NAD+ metabolism to mitigate multiple organ fibrosis

The processes underlying synchronous multiple organ fibrosis in systemic sclerosis (SSc) remain poorly understood. Age-related pathologies are associated with organismal decline in nicotinamide adenine dinucleotide (NAD⁺) that is due to dysregulation of NAD⁺ homeostasis and involves the NADase CD38. We now show that CD38 is upregulated in patients with diffuse cutaneous SSc, and CD38 levels in the skin associate with molecular fibrosis signatures, as well as clinical fibrosis scores, while expression of key NAD⁺-synthesizing enzymes is unaltered. Boosting NAD⁺ via genetic or pharmacological CD38 targeting or NAD⁺ precursor supplementation protected mice from skin, lung, and peritoneal fibrosis. In mechanistic experiments, CD38 was found to reduce NAD⁺ levels and sirtuin activity to augment cellular fibrotic responses, while inhibiting CD38 had the opposite effect. Thus, we identify CD38 upregulation and resulting disrupted NAD⁺ homeostasis as a fundamental mechanism driving fibrosis in SSc, suggesting that CD38 might represent a novel therapeutic target.

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CD38 shows elevated expression in skin biopsies of patients with systemic sclerosis

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Elevated CD38 is associated with reduced NAD⁺ and augmented fibrotic responses

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Genetic loss of CD38 is associated with increased NAD⁺ levels and attenuated fibrosis

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NAD⁺ boosting via CD38 inhibition or NR supplementation prevents multi-organ fibrosis

High-precision strain-insensitive temperature sensor based on an optoelectronic oscillator

We have proposed and experimentally demonstrated a high-precision and strain-insensitive temperature sensor based on an optoelectronic oscillator (OEO). The oscillation frequency of the OEO is determined by the single passband microwave photonic filter (MPF) by using stimulated Brillouin scattering (SBS). The sensing fiber, which acts as the SBS gain medium, is exposed to temperature variations. The Brillouin frequency shift (BFS) changes along with the temperature. Since the central frequency of the MPF is a function of the BFS, the oscillation frequency of the OEO is varied. Besides, due to the mode competition in the OEO, the influence of the strain is eliminated. Thus, the temperature variations can be estimated through measuring the oscillation frequency. We carry out a proof-to-concept experiment. Temperature sensing with a high sensitivity of 1.00745 MHz/°C is achieved. The maximum measurement error of temperature obtained is within ± 0.5 °C. The proposed scheme has merits of simplicity and compact configuration. In addition, the proposed temperature sensor can realize quasi-distributed measurement by utilizing wavelength division multiplexing (WDM).

Enrichment of Polyunsaturated Fatty Acids from Phyllanthus emblica L. Seed Oil by Urea Inclusion

Polyunsaturated fatty acids are essential to human nutrition. Phyllanthus emblica L. seed oil serves as a source of enrichment for the preparation of polyunsaturated fatty acids by urea inclusion technique. Under optimal conditions (6 g urea per 3 mL free fatty acids, crystallization temperature of −6°C, and crystallization time of 19 h), the purity of polyunsaturated fatty acids was up to 98.47% and the yield was 71.85%. The urea-polyunsaturated fatty acids inclusion complex was analyzed using differential scanning calorimetry, Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy/energy, and dispersive X-ray spectroscopy. The results showed that polyunsaturated fatty acids can be successfully separated by urea inclusion fractionation. The filled and hollow hexagonal prisms of urea crystal were clearly observed. In addition, the macroscopic and microscopic morphology of palmitic acid-urea inclusion were studied after washing with solvents using scanning electron microscopy and X-ray diffraction analysis to understand the involvement of guest molecules in the hexagonal crystal structure. The results showed that washing with solvents could not remove all the palmitic acid in the hexagonal structure of the urea inclusion complex, and the formation of hexagonal structure needed the support of involved guest molecules.

Association between genetic variants in p53 binding sites and risks of osteosarcoma in a Chinese population: a two-stage case-control study

Osteosarcoma (OS) is one of the most common bone malignancies in children and adolescents. To date, inaugural mechanism of OS was considered as a complex process and was still not clear. The p53 gene, most important tumor suppressors, was associated with risk of many tumors, including OS. In current study, we evaluated the relationship between genetic variation of the p53 binding site and the OS susceptibility through a two-stage case-control study in Chinese population. We found that rs1295925 (OR = 0.85; 95 CI = 0.76-0.94; P = 0.003) and rs3787547 (OR = 1.27; 95 CI = 1.11-1.45; P = 4.0 × 10^-4) was significantly with OS susceptibility. Compared with those with rs1295925-TT genotype, and the risk of OS was significantly lower in individuals with CT genotype (OR = 0.77; 95 CI = 0.65-0.92) and CC genotype (OR = 0.75; 95 CI = 0.60-0.93). Compared with those with rs3787547-GG genotype, and the risk of OS was significantly higher in individuals with AG genotype (OR = 1.32; 95 CI = 1.10-1.58) and AA genotype (OR = 1.46; 95 CI = 1.11-1.92). To sum up, our results prove that SNP rs1295925 and rs3787547 play an important role in the etiology of OS, suggesting them as the potential genetic modifier for OS development.

Real-time reference-based dynamic phase retrieval algorithm for optical measurement

To study dynamic behaviors of a phenomenon, measuring the evolving field of a specimen/material/structure is required. Optical interferometry, as a full-field, non-contact, and highly sensitive optical measurement technique, has been applied, where the evolving field is represented as dynamic phase distribution. A dynamic phase retrieval algorithm, called least-squares with 3 unknowns (LS3U), which estimates the phase change between each two consecutive patterns by a least-squares fitting method and denoises the phase change by a windowed Fourier filtering (WFF) algorithm, has been shown to be a simple yet effective algorithm. However, LS3U is computationally expensive, restricting its potential application in real-time dynamic phase retrieval systems. In this paper, a real-time LS3U algorithm powered by GPU parallel computing is proposed, with which frame rates of up to 64.5 frames per second (fps) and 131.8 fps are achieved on NVIDIA's GTX 680 and GTX 1080 graphics cards, respectively.

Ultrasonic guided percutaneous ethanol injection with or without combined radiofrequency ablation for hepatocellular carcinomas

OBJECTIVE

The aim of this retrospective study was to evaluate whether radiofrequency ablation (RFA) combined percutaneous ethanol injection (PEI) in the management of hepatocellular carcinoma (HCC) improves treatment outcomes.

PATIENTS AND METHODS

We retrospectively included 66 HCC patients who received RFA or RFA plus PEI from February 2011 to January 2014 in Jingmen No. 1 People's Hospital. Moreover, 31 cases received RFA plus PEI as the experiment group and 35 subjects treated with RFA aloe as the control group. The overall survival and treatment related complications were compared between the two groups.

RESULTS

For RFA group, the 1-year, 2-year, and 3-year survival rate were 82.0%, 69.3%, and 30.7%, respectively, with the median survival time of 27.1 months. For RFA plus PEI group, the 1-year, 2-year, and 3-year survival rate were 97.1%, 73.9%, and 37.5%, respectively, with the median survival time of 33.6 months. The overall survival of the two groups was not statistical different with the hazard ratio of 1.48 (P > 0.05); three cases of treatment associated complications were found in RFA group with 1 abscess, 1 pleural effusion, and 1 portal vein thrombosis. Moreover, 2 cases of complication were recorded in RFA plus PEI group with 1 pleural effusion and 1 portal vein thrombosis. The complicated incidence rate was not statistical different between the two groups (P < 0.05).

CONCLUSION

The combination treatment of HCC was safe and had a slightly higher primary effectiveness rate than RFA alone.

Affectivity during social behaviour in a schizophrenic-like rat

Introduction

Rats are social animals that produce high-frequency whistles said to reflect their underlying affective state. Injecting rats with a glutamate agonist (domoic acid) at a sensitive period of brain development, models aspects of schizophrenia. This is known as the neonatal DOM model.

Aims

We investigated whether DOM rats display altered social behaviour – as seen in patients with schizophrenia – using their high-frequency whistles as a proxy for the emotional valence of social situations.

Methods

We used 19 male Sprague Dawley rats, injected with either a low-dose of domoic acid or saline at postnatal days 8 to 14. The social behaviour of the rats was investigated at four levels:

– anticipation of social interaction;

– dyadic encounter;

– three-chamber test;

– tickling.

Tests were carried out at postnatal days 34 to 40 and 50 to 56. Rat whistles were recorded on all days of testing.

Results

In progress.

Conclusions

The interest in rat whistles as a supplement to traditional behavioural tests has increased. New software allows for detailed qualitative analysis of the whistle subtypes and thus new complexity to their interpretation. This study can help unravel information encoded in the whistles and shed light on the social behaviour of the DOM rat thus investigating it is applicability as a model of schizophrenia.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

[Antiangiogenic drugs enhance the ability of invasion and metastasis of breast cancer cells under serum starvation and hypoxia]

OBJECTIVE

To investigate the ability of invasion and migration of breast cancer MDA-MB-231 cells under serum starvation and hypoxia, and the effect of antiangiogenic drugs, rh-endostatin and bevacizumab, on the ability of invasion and migration of breast cancer cells under serum starvation and/or hypoxia, in order to explore the potential risk of antiangiogenic therapy in clinics.

METHODS

The cells were randomized into 4 groups, i.e., group A: 10% fetal bovine serum (FBS) group; group B: hypoxia + 10% FBS group; group C: serum starvation group; group D: hypoxia + serum starvation group; each group was further divided into three subgroups as blank control, treated with rh-endostatin and bevacizumab, respectively. Cell counting kit-8 (CCK-8) was used to assess the inhibition rate of cell growth induced by endostatin and bevacizumab, in order to determine the proper working concentration and time of the two drugs. Transwell assay was conducted to detect the cell invasion and migration in vitro. The expressions of c-Met and MMP-9 were detected by Western blot. The cells treated with rh-endostatin or bevacizumab under serum starvation were tested by hybridization using Exiqon miBase 18.0 microarray. The miRNAs which exibited significant differences (P < 0.05) in miRNA hybridization were verified by real-time PCR assay.

RESULTS

CCK-8 assay showed that the inhibition rates of MDA-MB-231 cells cultured with 800 mg/L rh-endostatin for 48 h and 24 h were (32.2 ± 2.5)% and (27.0 ± 1.3)%, respectively, showing a significant difference (P = 0.023). The inhibition rates of MDA-MB-231 cells cultured with 80 mg/L bevacizumab for 48 h and 24 h were (30.5 ± 1.4) % and (26.1 ± 2.4) %, respectively, showing also a significant difference (P = 0.015). The Transwell assay showed that in the starvation blank group, the number of invaded and penetrated cells were 28.8 ± 2.2 and 31.4 ± 1.5, respectively, significantly different from that in the rh-endostatin and bevacizumab groups (P < 0.05). The relative expressions of c-Met and MMP-9 were 0.213 ± 0.017 and 0.542 ± 0.048, respectively, with a significant difference from those of the groups treated with each drug (P < 0.05 for both). The numbers of penetrated cells in the Transwell assay treated with rh-endostatin in hypoxia were 17.5 ± 2.1 and 16.5 ± 2.8, respectively, and the numbers of penetrated cells in the Transwell assay treated with bevacizumab were 16.3 ± 3.5 and 17.5 ± 2.4, respectively, showing no significant difference among them (P > 0.05 for both). The ability of migration and invasion of MDA-MB-231 cells and the expression of c-Met and MMP-9 were not impacted by hypoxia (P > 0.05). Real-time PCR assay showed that only the levels of miR-2355 and miR375 were significantly and stably decreased in the cells which had increased ability of invasion and migration. The relative expression levels of miR375 and miR-2355 in the serum starvation blank group were 0.550 ± 0.036 and 0.852 ± 0.121, respectively, significantly lower than that in the groups treated with rh-endostatin or bevacizumab (P<0.05). In the serum starvation group, the expression levels of miR375 and miR-2355 of cells treated with rh-endostatin were 0.295 ± 0.012 and 0.253 ± 0.011, and the expression levels of cells treated with bevacizumab were 0.234 ± 0.020 and 0.309 ± 0.022, respectively, (P > 0.05 for all). Compared with the serum starvation blank group, the expression levels of miR2355 and miR375 were significantly decreased when cells were treated with rh-endostatin/bevacizumab under serum starvation, but no significant difference was found between the two drugs (P > 0.05). However, hypoxia did not affect the expressions of miR2355 and miR375 (P > 0.05).

CONCLUSIONS

The results of this study suggest that serum starvation can increase the ability of invasion and migration of breast cancer cells. Furthermore, both rh-endostatin and bevacizumab may enhance their invasion and penetration ability under serum starvation condition.

Improved generalized regularized phase tracker for demodulation of a single fringe pattern

A generalized regularized phase tracker (GRPT) for demodulation of a single fringe pattern was recently proposed. It is very successful for many fringe patterns. However, the GRPT has poor performance in the area where the fringe pattern is sparse. An improved GRPT (iGRPT) with two novel improvements is proposed to overcome the problem. First, the fixed window used in the GRPT is replaced by a spatially adaptive window. Second, a background regularization term and a modulation regularization term are incorporated in the cost function. With these two improvements, the proposed iGRPT can successfully demodulate sparse fringes and thus improves the demodulation capability of the GRPT. Simulation and experimental results are presented to verify the performance of the iGRPT.

A feasibility study for determining ablative margin with 3D-CEUS-CT/MR image fusion after radiofrequency ablation of hepatocellular carcinoma

PURPOSE

To explore the feasibility and value of 3D-CEUS-CT/MR image fusion in evaluating ablative margin (AM) after radiofrequency ablation of hepatocellular carcinoma.

METHODS AND MATERIALS

There were 49 HCC in 41 patients enrolled in our prospective study. The AM were evaluated with 3D-CEUS-CT/MR image fusion, the results were divided into two groups: in group A, the tumor was completely ablated with a 5 mm AM; in group B, the tumor was completely ablated, but a 5 mm AM was not obtained. The time used in US-CT/MR image fusion and 3 D image post-processing, the technical success rate of 3D-CEUS-CT/MR image fusion and the relation between LTP and AM were observed.

RESULTS

The time taken for US-CT/MR image fusion and 3 D image post-processing was 9.2 ± 2.1 min (6 - 12 min), 14.6 ± 2.6 min (9 - 20 min), respectively. The technical success rate of 3D-CEUS-CT/MR image fusion was 81.6 % (40/49). 27 HCC had sufficient AM (group A) and 13 HCC had insufficient AM (group B). The LTP rates in groups A and B were 0/27 and 4/13, respectively. There was a significant difference between groups A and B (P = 0.002). There was a significant negative correlation between LTP and AM (r = -1.000, P< 0.001), and the locations of LTP and insufficient AM were concordant.

CONCLUSIONS

The results suggest that 3D-CEUS-CT/MR image fusion is feasible and useful in evaluating the AM after HCC ablation.

A generalized regularized phase tracker for demodulation of a single fringe pattern

The regularized phase tracker (RPT) is one of the most powerful approaches for demodulation of a single fringe pattern. However, two disadvantages limit the applications of the RPT in practice. One is the necessity of a normalized fringe pattern as input and the other is the sensitivity to critical points. To overcome these two disadvantages, a generalized regularized phase tracker (GRPT) is presented. The GRPT is characterized by two novel improvements. First, a general local fringe model that includes a linear background, a linear modulation and a quadratic phase is adopted in the proposed enhanced cost function. Second, the number of iterations in the optimization process is proposed as a comprehensive measure of fringe quality and used to guide the demodulation path. With these two improvements, the GRPT can directly demodulate a single fringe pattern without any pre-processing and post-processing and successfully get rid of the problem of the sensitivity to critical points. Simulation and experimental results are presented to demonstrate the effectiveness and robustness of the GRPT.

Molecular characterization and pathogenicity of swine influenza H9N2 subtype virus A/swine/HeBei/012/2008/(H9N2)

The H9N2 subtype influenza virus (IV) is a remarkable member of the influenza A viruses because it can infect not only chickens, ducks and pigs, but also humans. Pigs are susceptible to both human and avian influenza viruses and have been proposed to be intermediate hosts for the generation of pandemic influenza viruses through reassortment or adaptation to the mammalian host. To further understand the genetic characteristics and evolution, we investigated the source and molecular characteristics of the H9N2 subtype swine influenza virus (SIV), and observed its pathogenicity in BALB/c mice. The BALB/c mice were inoculated intranasally with 100 median mouse infectious dose of A/swine/HeBei/012/2008/(H9N2) viruses to observe the pathogenicity. The HA, NP, NA and M gene were cloned, sequenced and phylogenetically analyzed with related sequences available in GenBank. The infected mice presented with inactivity, weight loss and laboured respiration, while the pathological changes were characterized by diffuse alveolar damage in the lung. The nucleotide and deduced amino acid sequence of HA, NP, NA and M gene was similar with that of A/chicken/Hebei/4/2008(H9N2). The HA protein contained 6 glycosylation sites and the motif of HA cleavage site was PARSSR GLF, which is characteristic of low pathogenic IV. In the HA, NP, M and NA gene phylogenetic trees, the isolate clustered with A/chicken/Hebei/4/2008(H9N2). The isolate possibly came from A/chicken/Hebei/4/2008(H9N2) and was partially varied during its cross-species spread.

Antidepressants inhibit proton currents and tumor necrosis factor-α production in BV2 microglial cells

Proton channels are gated by voltage and pH gradients, and play an important role in the microglial production of pro-inflammatory cytokines, which are known to be suppressed by antidepressants. In the present study we tested the hypothesis that cytokine inhibition by antidepressants is due to an inhibitory action on proton currents by comparing their effects on tumor necrosis factor-α production with the effects on the proton currents in BV2 murine microglial cells. Imipramine, amitriptyline, desipramine and fluoxetine potently and reversibly inhibited proton currents at micromolar concentrations at an intracellular/extracellular pH gradient of 5.5/7.3. Raising extracellular pH to 8.3 sped up the rate and enhanced the extent of block whereas raising intracellular pH to 6.3 reduced the blocking potency of imipramine. These results support a mechanism where the uncharged drug form penetrates the cell membrane, and the charged form blocks the proton channel from the internal side of membrane. This mode of action was corroborated by an experiment with imipraminium, a permanently charged quaternary derivative, which showed far less block compared to imipramine. The lipopolysaccharide-induced release of tumor necrosis factor-α was inhibited by imipramine at concentrations comparable to those inhibiting the proton current. These results support the hypothesis that tumor necrosis factor-α inhibition by imipramine is related to its inhibitory effects on proton channels.

Combination of resveratrol and antiandrogen flutamide has synergistic effect on androgen receptor inhibition in prostate cancer cells

Agents targeting the androgen receptor (AR) axis are critical for chemoprevention and treatment of prostate cancer (PCa) at all stages of the disease. Combination molecular targeted therapy may improve overall efficacy. The combination of dietary compound resveratrol with known therapeutic agents, such as the antiandrogen flutamide, may be particularly attractive due to the pharmacological safety of resveratrol.

MATERIALS AND METHODS

Resveratrol, 5α-dihydrotestosterone and flutamide were used in various experiments using mostly LNCaP cell line. Quantitative reverse transcription polymerase chain reaction (qRT-PCR), Western blots, and luciferase assay were utilized to examine the levels of AR mRNA, and protein and transcriptional activity in response to treatments. Growth proliferation assays were performed in three cell lines (LNCaP, PC3 and Du145).

RESULTS

Treatment of LNCaP cells with resveratrol (1-100 μM) resulted in the inhibition of androgen-promoted growth, inhibition of AR transcriptional activity and decrease in the AR and prostate-specific antigen protein levels through degradation pathways. The combination of resveratrol with flutamide had a synergistic effect on down-regulation of AR.

CONCLUSION

Resveratrol works in concert with antiandrogen flutamide to reduce the amount and activity of AR, suggesting new therapeutic strategies for the treatment of PCa.

Dynamic phase retrieval in temporal speckle pattern interferometry using least squares method and windowed Fourier filtering

An algorithm for dynamic phase retrieval in temporal speckle pattern interferometry using least squares method and windowed Fourier filtering is proposed. The least squares method is used to evaluate the phase change between two speckle patterns provided that the phase of either one speckle pattern has been estimated. The windowed Fourier filtering is used to eliminate the noise in the phase change. Based on these two techniques, the proposed algorithm determines the phase of the initial speckle pattern by phase shifting method at first, then the phase of the rest speckle patterns are retrieved by sequentially evaluating the phase changes between every two consecutive speckle patterns. The algorithm solves the problem of speckle decorrelation by refreshing the reference image frame by frame, and also avoids the problem of error accumulation during the reference image refreshing process by the windowed Fourier filtering. Two experimental results are presented to demonstrate the effectiveness and robustness of the proposed algorithm.

Targeting prostate cancer angiogenesis through metastasis-associated protein 1 (MTA1)

BACKGROUND

Metastasis-associated protein 1 (MTA1) is overexpressed in many forms of cancer types but its role in prostate cancer (PCa) progression and metastasis has not been explored. In this study, we addressed the functional and biological role of MTA1 in PCa.

METHODS

Gene expression profiling was used to determine MTA1 overexpression during PCa cell-bone interaction. Immunohistochemistry was used to detect MTA1 on tissue microarrays (TMA) and vascular endothelial growth factor (VEGF), CD31, and Ki67 in xenografts. We used retroviral or lentiviral RNAi transduction of PCa cells to establish MTA1 knockdowns. RT-PCR, Western blot, invasion, and endothelial cell migration assays were used to characterize the cells in vitro. The role of MTA1 in PCa tumorigenesis was evaluated in mouse xenografts.

RESULTS

We identified MTA1 as a component of bone metastasis signature in PCa, which suggested a possible role for MTA1 in PCa progression and metastasis. MTA1 was expressed at higher levels in PCa cell lines than in normal prostate epithelial cells. Silencing MTA1 significantly suppressed the invasion and angiogenic activity of the cells in vitro and delayed tumor formation and development in mouse xenografts. Tumors that express MTA1 had higher proliferative indices, secreted higher levels of VEGF and were more vascularized. Analysis of the human TMA showed positive correlation between MTA1 nuclear localization/staining intensity and PCa aggressiveness.

CONCLUSIONS

MTA1 pro-angiogenic and pro-invasive functions create permissive environment for PCa tumor growth and likely support metastasis. Taken together with its predictive values, MTA1 can be utilized both as a prognostic marker and a therapy target in PCa.

Abstract A24: Resveratrol-induced and MTA1-associated miRNAs in prostate cancer prevention

Prostate cancer (PCa) remains one of the most frequently diagnosed cancers in men in Western countries. Since noticeable geographic variations have been observed in the incidence of PCa, studies have implicated a “Western” diet in the development of PCa. Because of this and the nature of PCa, which is typically diagnosed in the elderly population wth a relatively slower rate of growth and progression, chemoprevention through dietary compounds promises to be an effective approach for PCa. Resveratrol (Res) (3,5,4’-trihydroxy-trans-stilbene), a natural compound found in grapes, peanuts and berries, is one of the most promising diet-derived chemopreventive agent with potential chemotherapeutic capacities. There is growing evidence that Res may contribute to chromatin remodeling that are important in cancer progression. Metastasis-associated protein 1 (MTA1), which is overexpressed in many cancer, is a part of nucleosome remodeling and deacetylation (NuRD) complex that mediates posttranslational modifications of histones and nonhistone proteins resulting in transcriptional gene silencing. The complex also contains histone deacetylases 1 and 2 (HDAC1 and 2). MTA1/HDAC1 subunit plays an essential role in governing deacetylation of histones and other proteins. We recently demonstrated that Res down-regulated MTA1 protein levels in PCa cells, leading to destabilization of MTA1/HDAC1/NuRD complex thus allowing acetylation and activation of tumor suppressor p53. MTA1 silencing by RNA interference further sensitized PCa cells to Res-dependent p53 acetylation, transcriptional activation of p21 and Bax and apoptosis. To further understand Res-induced MTA1-associated epigenetic alterations, we analyzed MTA1-associated and Res-induced microRNAs expression changes using LNCaP cells expressing and silenced for MTA1. We found that expression of 13 miRNA was increase, and 17 miRNAs was decreased in cells silenced for MTA1 gene. In addition, 28 miRNAs were overexpresed, and 23 miRNAs were degreased under Res treatment. Among these miRNAs were some with well-characterized cancer association, such as let-7g, miR-16-2, miR-26a, miR-20b, miR-27a, miR-22, miR-34a, miR-92 and others. The predicted targets for the overlapping miRNAs are significantly enriched for protein-coding oncogenes and tumor suppressors. Our data indicate that MTA1-associated miRNAs are involved in Res-mediated anticancer and preventive effects in prostate cancer.

Citation Information: Cancer Prev Res 2010;3(12 Suppl):A24.

Fast frequency-guided sequential demodulation of a single fringe pattern

Fast frequency-guided sequential demodulation (FFSD) for demodulating a single closed-fringe pattern is proposed as an improvement of frequency-guided sequential demodulation (FSD). Instead of using optimization to estimate the local frequencies for determining the sign of the phase, the FFSD estimates the local frequencies by directly calculating the gradient of the obtained phase with an undetermined sign. This improvement considerably reduces the computational complexity of the FSD and leads to a faster and simpler method. Simulated and experimental fringe patterns are used to test the proposed method and show that the demodulation speed of FFSD is about 150 times faster than that of the FSD, while the robustness and accuracy remain almost the same.

Evaluating biliary anatomy and variations in living liver donors by a new technique: three-dimensional contrast-enhanced ultrasonic cholangiography

Accurate assessment of the biliary anatomy is important for the safety of liver donors in living donor liver transplantation (LDLT). We evaluated the biliary anatomy and variations of 12 living liver donors with 3-D contrast-enhanced ultrasonic cholangiography (3-D CEUSC) by injecting microbubble contrast agents into the common hepatic ducts intraoperatively. Two radiologists assessed the diagnostically adequate, delineation of biliary branch orders, visibility scores (grades 0 to 3) and anatomical patterns of the intrahepatic biliary tree by consensus. The results were compared with findings on intraoperative cholangiography (IOC) and surgery. 3-D CEUSC successfully demonstrated the spatial structure of the intrahepatic biliary tree in all 12 donors. The maximum branching order of intrahepatic bile ducts displayed on 3-D CEUSC was the fifth order in the right lobe and fourth order in the left lobe of the liver, respectively. The visibility scores of the first-order (3.00 +/- 0.00) and second-order (2.67 +/- 0.69) branches were significantly (p < 0.001) higher than that of the third-order (1.98 +/- 1.13) branches, whereas visibility scores of the second-order (2.88 +/- 0.34) and third-order (2.44 +/- 1.01) branches in the right lobe were significantly (p = 0.040 and p < 0.001, respectively) higher than those in the left lobe (2.46 +/- 0.88 and 1.33 +/- 0.99). The 3-D CEUSC images of the 12 donors were diagnostically adequate for evaluating the biliary anatomy. Normal biliary pattern in nine donors and biliary variations in three donors were confirmed by both IOC and surgical findings. 3-D CEUSC may be a potential alternative to IOC in the evaluation of biliary anatomical variation before graft harvesting in LDLT.

Resveratrol enhances p53 acetylation and apoptosis in prostate cancer by inhibiting MTA1/NuRD complex

Dietary compounds and epigenetic influences are well recognized factors in cancer progression. Resveratrol (Res), a dietary compound from grapes, has anticancer properties; however, its epigenetic effects are understudied. Metastasis-associated protein 1 (MTA1) is a part of the nucleosome remodeling deacetylation (NuRD) corepressor complex that mediates posttranslational modifications of histones and nonhistone proteins resulting in transcriptional repression. MTA1 overexpression in prostate cancer (PCa) correlates with tumor aggressiveness and metastasis. In this study, we have identified a novel MTA1-mediated mechanism, by which Res restores p53-signaling pathways in PCa cells. We show, for the first time, that Res causes down-regulation of MTA1 protein, leading to destabilization of MTA1/NuRD thus allowing acetylation/activation of p53. We demonstrated that MTA1 decrease by Res was concomitant with accumulation of Ac-p53. MTA1 knockdown further sensitized PCa cells to Res-dependent p53 acetylation and recruitment to the p21 and Bax promoters. Furthermore, MTA1 silencing maximized the levels of Res-induced apoptosis and pro-apoptotic Bax accumulation. HDAC inhibitor SAHA, like MTA1 silencing, increased Res-dependent p53 acetylation and showed cooperative effect on apoptosis. Our results indicate a novel epigenetic mechanism that contributes to Res anticancer activities: the inhibition of MTA1/NuRD complexes due to MTA1 decrease, which suppresses its deacetylation function and allows p53 acetylation and subsequent activation of pro-apoptotic genes. Our study identifies MTA1 as a new molecular target of Res that may have important clinical applications for PCa chemoprevention and therapy, and points to the combination of Res with HDAC inhibitors as an innovative therapeutic strategy for the treatment of PCa.

MEF-2 regulates activity-dependent spine loss in striatopallidal medium spiny neurons

Striatal dopamine depletion profoundly reduces the density of spines and corticostriatal glutamatergic synapses formed on D(2) dopamine receptor expressing striatopallidal medium spiny neurons, leaving D(1) receptor expressing striatonigral medium spiny neurons relatively intact. Because D(2) dopamine receptors diminish the excitability of striatopallidal MSNs, the pruning of synapses could be a form of homeostatic plasticity aimed at restoring activity into a preferred range. To characterize the homeostatic mechanisms controlling synapse density in striatal medium spiny neurons, striatum from transgenic mice expressing a D(2) receptor reporter construct was co-cultured with wild-type cerebral cortex. Sustained depolarization of these co-cultures induced a profound pruning of glutamatergic synapses and spines in striatopallidal medium spiny neurons. This pruning was dependent upon Ca(2+) entry through Cav1.2 L-type Ca(2+) channels, activation of the Ca(2+)-dependent protein phosphatase calcineurin and up-regulation of myocyte enhancer factor 2 (MEF2) transcriptional activity. Depolarization and MEF2 up-regulation increased the expression of two genes linked to synaptic remodeling-Nur77 and Arc. Taken together, these studies establish a translational framework within which striatal adaptations linked to the symptoms of Parkinson's disease can be explored.

Kalirin-7 controls activity-dependent structural and functional plasticity of dendritic spines

Activity-dependent rapid structural and functional modifications of central excitatory synapses contribute to synapse maturation, experience-dependent plasticity, and learning and memory and are associated with neurodevelopmental and psychiatric disorders. However, the signal transduction mechanisms that link glutamate receptor activation to intracellular effectors that accomplish structural and functional plasticity are not well understood. Here we report that NMDA receptor activation in pyramidal neurons causes CaMKII-dependent phosphorylation of the guanine-nucleotide exchange factor (GEF) kalirin-7 at residue threonine 95, regulating its GEF activity, leading to activation of small GTPase Rac1 and rapid enlargement of existing spines. Kalirin-7 also interacts with AMPA receptors and controls their synaptic expression. By demonstrating that kalirin expression and spine localization are required for activity-dependent spine enlargement and enhancement of AMPAR-mediated synaptic transmission, our study identifies a signaling pathway that controls structural and functional spine plasticity.

Dopaminergic control of corticostriatal long-term synaptic depression in medium spiny neurons is mediated by cholinergic interneurons

Long-term depression (LTD) of the synapse formed between cortical pyramidal neurons and striatal medium spiny neurons is central to many theories of motor plasticity and associative learning. The induction of LTD at this synapse is thought to depend upon D(2) dopamine receptors localized in the postsynaptic membrane. If this were true, LTD should be inducible in neurons from only one of the two projection systems of the striatum. Using transgenic mice in which neurons that contribute to these two systems are labeled, we show that this is not the case. Rather, in both cell types, the D(2) receptor dependence of LTD induction reflects the need to lower M(1) muscarinic receptor activity-a goal accomplished by D(2) receptors on cholinergic interneurons. In addition to reconciling discordant tracts of the striatal literature, these findings point to cholinergic interneurons as key mediators of dopamine-dependent striatal plasticity and learning.

Opioid receptor antagonists increase [Ca2+]i in rat arterial smooth muscle cells in hemorrhagic shock

AIM

To examine the effects of opioid receptor antagonists and norepinephrine on intracellular free Ca2+ concentration ([Ca2+]i) in mesenteric arterial (MA) smooth muscle cells (SMC) isolated from normal and hemorrhagic shocked rats in the vascular hyporesponse stage.

METHODS

The rat model of hemorrhagic shock was made by withdrawing blood to decrease the artery mean blood pressure to 3.73-4.26 kPa and keeping at the level for 3 h. [Ca2+]i of vascular smooth muscle cells (VSMC) were detected by the laser scan confocal microscopy.

RESULTS

In the hyporesponse VMSC of rats in hemorrhagic shock, selective delta-, kappa-, and mu-opioid receptor antagonists (naltrindole, nor-binaltorphimine, and beta-funaltrexamine, 100 nmol/L) as well as norepinephrine 5 micromol/L significantly increased [Ca2+]i by 47 %+/-13 %, 37 %+/-14 %, 33 %+/-10 %, and 54 %+/-17 %, respectively, although their effects were lower than those in the normal rat cells (the increased values were 148 %+/-54 %, 130 %+/-44 %, 63 %+/-17 % and 110 %+/-38 %, respectively); and the norepinephrine-induced increase in [Ca2+]i was further augmented by three delta-, kappa-, and mu-opioid receptor antagonists (50 nmol/L, respectively) application (from 52 %+/-16 % to 99 %+/-29 %, 146 %+/-54 % and 137 %+/-47 %, respectively).

CONCLUSION

The disorder of [Ca2+]i regulation induced by hemorrhagic shock was mediated by opioid receptor and alpha-adrenoceptor, which may be partly responsible for the vascular hyporesponse, and the opioid receptor antagonists improved the response of resistance arteries to vascular stimulants in decompensatory stage of hemorrhagic shock.

Opioid receptor antagonists modulate Ca2+-activated K+ channels in mesenteric arterial smooth muscle cells of rats in hemorrhagic shock

Previous study has indicated a significant enhancement of activity of large-conductance Ca2+-activated K+ channel (BKCa) in mesenteric arterial vascular smooth muscle cells isolated from rats in vascular hyporesponsive stage of hemorrhagic shock. In the present study, the effect of opioid receptor antagonism on BKCa activity in the vascular smooth muscle cells of rats in the hyporesponse stage of hemorrhagic shock was investigated by using inside-out configuration of the patch-clamp technique. The results showed that naloxone (10 microM) down-regulated the activity of BKCa by reducing open probability (Po) and open frequency of the channels. The reduction of Po resulted from a decrease of mean open time and an increase of the slow closed time constant. Naltrindole and nor-binaltorphimine (100 nM) had the similar effects to that of naloxone, but no significant effect of beta-funaltrexamine (100 nM) on the activity of the channels could be found. These results suggest that delta- and kappa-opioid receptors, but not mu-receptors, may be involved in the regulation of BKCa in vascular hyporesponse stage, and that inhibition of BKCa may be one of the mechanisms of the opioid receptor antagonists improving the response of resistance arteries to vasoactive stimulants during the decompensatory stage of hemorrhagic shock.

Modulation of Ca2+ channels by opioid receptor antagonists in mesenteric arterial smooth muscle cells of rats in hemorrhagic shock

The effects of hemorrhagic shock on Ba currents ( ) via Ca channels and the regulation of the channels in the vascular hyporesponse stage of hemorrhagic shock by opioid receptor antagonists were examined by using the whole-cell recording of patch-clamp technique in mesenteric arterial smooth muscle cells of rats. The results showed that hemorrhagic shock induced an inhibition of Ca channels in the cells; 10 micro M of naloxone and 100 n of naltrindole, nor-binaltorphimine, and beta-funaltrexamine increased the in the cells of rats in shock. After inhibition of protein kinase C by using 1-(5-isoquindinesulfonyl)-2-methylpiperazine via electrodes, the enhancement of by the antagonists was not observed. These results suggested that the inhibition of Ca channel induced by hemorrhagic shock was mediated by delta-, kappa-, and mu -opioid receptors in the cells and may be partly responsible for vascular hyporesponse. The enhancement of was mediated by activation of protein kinase C and may be responsible for the antagonist-caused improvement in the response of resistance arteries to vasoactive stimulants at the decompensatory stage of hemorrhagic shock.

[Hemorrhagic shock induces changes in large-conductance Ca(2+) dependent K+ channel activity in mesenteric arterial smooth muscle cells of rats]

The purpose of the present study was to detect changes in the activity of large-conductance Ca(2+)activated K(+) channel (BK(Ca)) during hemorrhagic shock (HS) in mesenteric arterial vascular smooth muscle cells using inside-out patches. The HS rat model was produced with withdrawing blood from the femoral artery. The results showed that the BK(Ca) activity was inhibited with decreased open probability (P(o)) and single-channel conductance. The decrease of P(o) resulted from an increase of the close time constant (tau(cs)) in the compensatory stage of HS, i.e.the term of hyperresponse of the muscle to norepinephrine (NE) (HS lasted for about 40 min). During the decompensation stage of HS, i.e. the period of hyporesponse to NE (HS developed for 3 h), the BK(Ca) activity was enhanced with the increase in single-channel conductance and P(o) which was a result of a decrease in tau(cs).

Dual effects of tetrandrine on calcium-activated potassium channels in pulmonary artery smooth muscle cells

AIM

To study the effects of tetrandrine (Tet) on calcium-activated potassium channels.

METHODS

Inside-out configuration of patch-clamp single channel recording techniques.

RESULTS

Tet 7.5 and 15 mumol.L-1 increased the open probability from control value 0.251 +/- 0.012 to 0.340 +/- 0.013 and 0.415 +/- 0.011, respectively (P < 0.01), decreased the close time from (61 +/- 15) ms to (33 +/- 10) and (28 +/- 11) ms, respectively (P < 0.01). But Tet 30 mumol.L-1 decreased the open probability and open time to (0.114 +/- 0.008) and (1.47 +/- 0.09) ms, respectively [P < 0.01 vs control (0.251 +/- 0.012) and (20 +/- 8) ms].

CONCLUSION

Tet has concentration-dependent dual effects on KCa channels in isolated rat pulmonary smooth muscle cells.

L-type calcium channel blockade mechanisms of panaxadiol saponins against anoxic damage of cerebral cortical neurons isolated from rats

AIM

To identify the changes of L-type Ca2+ channel on cerebral cortical neurons of rats during anoxia and the protective mechanisms of panaxadiol saponins (PDS) against anoxic injury.

METHODS

Patch-clamp technique of cell-attached configuration and in vitro cerebral anoxic modle built with actuely isolated cortical cells of Wistar rats.

RESULTS

The open time of L-type Ca2+ channel of cortical neurons increased significantly from (2.85 +/- 0.21) ms to (9.1 +/- 1.0) ms (P < 0.01) under anoxia. The particular change was a long-lasting open, which was more than 20 ms in some cases. At the same time, the close time decreased from (38 +/- 8) ms to (10 +/- 3) ms (P < 0.01) and the open-state probability raised from (0.047 +/- 0.008) to (0.165 +/- 0.025) (P < 0.01). PDS (1.5 g.L-1) inhibited the activity of L-type Ca2+ channel both in normal and anoxic condition [open time from (2.23 +/- 0.47) ms and (9.1 +/- 1.0) ms to (1.03 +/- 0.25) ms and (2.1 +/- 0.4) ms; close time from (38 +/- 10) ms and (10 +/- 3) ms to (74 +/- 16) ms and (46 +/- 10 ms); open-state probability from (0.043 +/- 0.006) and (0.165 +/- 0.025) to (0.012 +/- 0.004) and (0.021 +/- 0.009), respectively, P all < 0.01]. The results of PDS were similar to those of verapamil, but were weaker compared with verapamil.

CONCLUSION

The L-type Ca2+ channels of rat cerebral cortical neurons were obviously opened during anoxia. The channels in normal and anoxic condition were effectively blocked by PDS. It was one of the important mechanisms by which PDS protected brain from the anoxic injury.

Finely stratified cylinder model for radially inhomogeneous cylinders normally irradiated by electromagnetic plane waves

A finely stratified cylinder model (FSCM) for calculation of the scattered fields of infinitely long, radially inhomogeneous, circular cylinders normally illuminated by electromagnetic plane waves is introduced for the first time, to our knowledge. Because of its capability of using a very large number of layers (more than 80,000), the model is useful for both continuous and discontinuous refractive-index profiles. Numerical results agree well with published solutions for radially inhomogeneous cylinders; for cylinders with a dimensionless size parameter larger than 60, results obtained with the FSCM agree with the geometric optics for both continuous and discontinuous refractive-index profiles.

Scattering of electromagnetic-plane waves by radially inhomogeneous spheres: a finely stratified sphere model

A new recursive algorithm to calculate the internal and scattered fields of finely stratified inhomogeneous spheres has been developed. No restriction on the number of layers-the thicknesses of which can be arbitrarily small-is imposed by this method. The number of layers is restricted only by the computer's capability: calculations with spheres with more than 10,000 layers were successfully performed with a HP work station. The new algorithm circumvents the limitations introduced by the numerical round-off errors encountered when using the previously developed recursive relations to calculate the ratios of Riccati-Bessel functions. Tests and calculations show that the method is stable and accurate for a large range of size parameters and optical properties. By employing the proposed algorithm, the problems encountered in analyzing the scattering by spheres with continuous-profile refractive indices can be solved with good accuracy.