Non-uniform image reconstruction for fast photoacoustic microscopy of histology imaging.

Photoacoustic microscopic imaging utilizes the characteristic optical absorption properties of pigmented materials in tissues to enable label-free observation of fine morphological and structural features. Since DNA/RNA can strongly absorb ultraviolet light, ultraviolet photoacoustic microscopy can highlight the cell nucleus without complicated sample preparations such as staining, which is comparable to the standard pathological images. Further improvements in the imaging acquisition speed are critical to advancing the clinical translation of photoacoustic histology imaging technology. However, improving the imaging speed with additional hardware is hampered by considerable costs and complex design. In this work, considering heavy redundancy in the biological photoacoustic images that overconsume the computing power, we propose an image reconstruction framework called non-uniform image reconstruction (NFSR), which exploits an object detection network to reconstruct low-sampled photoacoustic histology images into high-resolution images. The sampling speed of photoacoustic histology imaging is significantly improved, saving 90% of the time cost. Furthermore, NFSR focuses on the reconstruction of the region of interest while maintaining high PSNR and SSIM evaluation indicators of more than 99% but reducing the overall computation by 60%.

microRNA-329 suppresses epithelial-to-mesenchymal transition and lymph node metastasis in bile duct cancer by inhibiting laminin subunit beta 3.

Bile duct cancer (BDC), also known as cholangiocarcinoma, is a highly desmoplastic cancer with a growth pattern characterized by periductal extension and infiltration. Studies have suggested that microRNAs (miRNAs) play an important role in BDC progression. Here we aim at investigating the effects of miR-329 on BDC development, focusing especially on epithelial-to-mesenchymal transition (EMT) in vitro and lymph node metastasis in vivo. Expression microarrays associated with BDC tissues were collected and differentially expressed genes were analyzed, followed by miRNA target prediction and verification. The role miR-329 played in BDC was examined using gain-of-function and loss-of-function methods. The expressions of miR-329, laminin subunit beta 3 (LAMB3), and EMT markers, in addition to cell proliferation, migration, and invasion were evaluated. Furthermore, nude mice models of BDC were established to observe tumor growth and metastatic lymph nodes. The LAMB3 was identified as an upregulated gene based on the GSE77984 and GSE45001 microarray analysis. LAMB3 was also predicted and confirmed to be a target gene of miR-329 by dual-luciferase reporter assay. Through further cell experiments, the EMT process was reversed, cell proliferation, invasion, and migration were suppressed, when miR-329 was upregulated. Furthermore, in vivo experiments exhibited that the overexpression of miR-329 inhibited tumor growth and the number of metastatic lymph nodes. This study provides in vivo and in vitro evidence that miR-329 inhibits BDC progression through translational repression of LAMB3. Therefore, the obtained results may aid as an experimental basis for improving prognosis of BDC.

Integration of Antibody Array Technology into Drug Discovery and Development.

Antibody arrays represent a high-throughput technique that enables the parallel detection of multiple proteins with minimal sample volume requirements. In recent years, antibody arrays have been widely used to identify new biomarkers for disease diagnosis or prognosis. Moreover, many academic research laboratories and commercial biotechnology companies are starting to apply antibody arrays in the field of drug discovery. In this review, some technical aspects of antibody array development and the various platforms currently available will be addressed; however, the main focus will be on the discussion of antibody array technologies and their applications in drug discovery. Aspects of the drug discovery process, including target identification, mechanisms of drug resistance, molecular mechanisms of drug action, drug side effects, and the application in clinical trials and in managing patient care, which have been investigated using antibody arrays in recent literature will be examined and the relevance of this technology in progressing this process will be discussed. Protein profiling with antibody array technology, in addition to other applications, has emerged as a successful, novel approach for drug discovery because of the well-known importance of proteins in cell events and disease development.

Lamprey: a model for vertebrate evolutionary research.

Lampreys belong to the superclass Cyclostomata and represent the most ancient group of vertebrates. Existing for over 360 million years, they are known as living fossils due to their many evolutionally conserved features. They are not only a keystone species for studying the origin and evolution of vertebrates, but also one of the best models for researching vertebrate embryonic development and organ differentiation. From the perspective of genetic information, the lamprey genome remains primitive compared with that of other higher vertebrates, and possesses abundant functional genes. Through scientific and technological progress, scientists have conducted in-depth studies on the nervous, endocrine, and immune systems of lampreys. Such research has significance for understanding and revealing the origin and evolution of vertebrates, and could contribute to a greater understanding of human diseases and treatments. This review presents the current progress and significance of lamprey research.

Application of multiplex immunoassay technology to investigations of ocular disease.

Eye-derived fluids, including tears, aqueous humour and vitreous humour often contain molecular signatures of ocular disease states. These signatures can be composed of cytokines, chemokines, growth factors, proteases and soluble receptors. However, the small quantities (<10 µl) of these fluids severely limit the detection of these proteins by traditional enzyme-linked immunosorbent assay or Western blot. To maximise the amount of information generated from the analysis of these specimens, many researchers have employed multiplex immunoassay technologies for profiling the expression or modification of multiple proteins from minute sample volumes.

Tunable nanogap devices for ultra-sensitive electrochemical impedance biosensing.

A wealth of research has been available discussing nanogap devices for detecting very small quantities of biomolecules by observing their electrical behavior generally performed in dry conditions. We report that a gold nanogapped electrode with tunable gap length for ultra-sensitive detection of streptavidin based on electrochemical impedance technique. The gold nanogap is fabricated using simple monolayer film deposition and in-situ growth of gold nanoparticles in a traditional interdigitated array (IDA) microelectrode. The electrochemical impedance biosensor with a 25-nm nanogap is found to be ultra-sensitive to the specific binding of streptavidin to biotin. The binding of the streptavidin hinder the electron transfer between two electrodes, resulting in a large increase in electron-transfer resistance (Ret) for operating the impedance. A linear relation between the relative Ret and the logarithmic value of streptavidin concentration is observed in the concentration range from 1 pM (picomolar) to 100 nM (nanomolar). The lowest detectable concentration actually measured reaches 1 pM. We believe that such an electrochemical impedance nanogap biosensor provides a useful approach towards biomolecular detection that could be extended to a number of other systems.

Deciphering Asthma Biomarkers with Protein Profiling Technology.

Asthma is a chronic inflammatory disease of the airways, resulting in bronchial hyperresponsiveness with every allergen exposure. It is now clear that asthma is not a single disease, but rather a multifaceted syndrome that results from a variety of biologic mechanisms. Asthma is further problematic given that the disease consists of many variants, each with its own etiologic and pathophysiologic factors, including different cellular responses and inflammatory phenotypes. These facets make the rapid and accurate diagnosis (not to mention treatments) of asthma extremely difficult. Protein biomarkers can serve as powerful detection tools in both clinical and basic research applications. Recent endeavors from biomedical researchers have developed technical platforms, such as cytokine antibody arrays, that have been employed and used to further the global analysis of asthma biomarker studies. In this review, we discuss potential asthma biomarkers involved in the pathophysiologic process and eventual pathogenesis of asthma, how these biomarkers are being utilized, and how further testing methods might help improve the diagnosis and treatment strain that current asthma patients suffer.

Selective detection toward quercetin and kaempferol on NH3-plasma treated carbon nanotubes modified glassy carbon electrode.

NH3-plasma treated multi-walled carbon nanotubes (pn-MWCNTs) were prepared based on the plasma technique and developed as sensing materials for detection of quercetin and kaempferol with the differential pulse voltammetry (DPV) and amperometric measurement. Such experimental parameters as pH values, accumulation potential and accumulation time were carefully investigated. The pn-MWCNTs modified electrode (pn-MWCNTs/GCE) was further explored for the analysis of quercetin and kaempferol in diluted blood serum and average recovery rates of 96.91 and 100.5% were obtained, respectively. In addition, the interference and stability measurements were evaluated under the optimized experimental conditions. More importantly, selective detection toward quercetin and kaempferol was achieved, and the proposed electrochemical sensing strategy was available to distinguish substances with similar oxidation potential.

[Mechanism of Wnt signaling pathway regulation by a truncated mutant of Axin2 in colorectal cancer].

BACKGROUND & OBJECTIVE: Axin2 gene which negatively regulates the Wnt signaling pathway was cloned recently. A truncated mutation of Axin2 (mtAxin2) is the most common mutation pattern in colorectal cancer (CRC) and could enhance the luciferase activity of T-cell factor (TCF). This study was to explore the mechanism of Wnt signaling pathway regulation by mtAxin2 in CRC. METHODS: The expression of beta-catenin in a mtAxin2-positive and a mtAxin2-negative CRC specimens was detected by immunohistochemistry. Plasmids containing wild-type or mutated Axin2 (pCMV-Flag-wtAxin2 and pCMV-Flag-mtAxin2) were constructed and co-transfected into 293 cells. The interactions of wtAxin2 and mtAxin2 with core components in Wnt signaling pathway was tested by co-immunoprecipitation (IP) and Western blot. TNT T3/T7 in vitro transcription and translation system were used to produce mtAxin2 and wtAxin2 proteins to verify the homodimerization of mtAxin2. Firefly and Renilla activities of mtAxin2 were detected with dual-luciferase report assay. Retinoid X receptor (RXR) and ecodysone receptor (ECR) plasmids were prepared for the experiment of restoration of TCF activity of mtAxin2. RESULTS: Immunohistochemistry showed that beta-catenin accumulated in the nuclei of mtAxin2-positive CRC cells and in cytoplasm of mtAxin2-negative CRC cells. Western blot showed that mtAxin2 bound to GSK-3beta, APC, beta-catenin, DVL-1 and PP2A as wtAxin2 did. After co-transfection of wtAxin2 and mtAxin2 in 293 cells, mtAxin2 competitively bound to beta-catenin. TNT T3/T7 experiment showed that wtAxin2 formed oligomers or dimers with Flag-wtAxin2, but not with Flag-mtAxin2. TCF activity in 293 cells was increased after transfection of pCMV-mtAxin2-RXR, but reduced after transfection of pCMV-mtAxin2-ECR or co-transfection of pCMV-mtAxin2-RXR and pCMV-mtAxin2-ECR, indicating the fusion of mtAxin2 and RXR formed dimers and restored its inhibitory effect on TCF activity. CONCLUSION: Because of loss of DIX domain, mtAxin2 can not form dimmers, disturbs the degradation of beta-catenin, and leads to the nuclear accumulation of beta-catenin and activation of Wnt signaling pathway.

[Clinical research of taxotere in treatment of metastatic breast cancer].

BACKGROUND & OBJECTIVE: Recently, high-dose docetaxel has been proved to be an effective antineoplastic drug in the treatment of metastatic breast cancer.However,there was a few reports about moderate-dose docetaxel and Adriamycin in the treatment of metastatic breast cancer. This study was designed to observe the response rate and toxic reaction of Taxotere and Taxotere plus Adriamycin in the treatment of metastatic breast cancer. METHODS: From September 1996 to April 2000, 34 cases with metastatic breast cancer, which were treated in Department of Oncology, The Second Central Hospital in Tianjin, were included in the study. For group A (14 cases), Taxotere single agent was administered at a dose of 75 mg/m(2) iv 1 hour. For group B, Taxotere was administered at a dose of 60 mg/m(2) combined with Adriamycin 50 mg/m(2) i.v. 1 hour. The same schedule for both groups was repeated every 21 days, with three cycles for all patients. RESULTS: The recent response rates of group A and group B were 57.14% (8/14) and 75.0% (15/20), respectively. The 2-and 4-year survival rates were 35.7%, 14.3% for group A, and 40.0%, 15.0% for group B. The median overall survival durations of group A and group B were 22 months and 23 months. The median overall response durations of these two groups were 10 and 11 months, respectively. The main adverse reactions of these two groups were neutropenia, nausea, vomiting, stomatitis, diarrhea, alopecia, fatigue, myalgia, fluid retention, and skin flushing. Grade 3 and grade 4 neutropenia occurred in group A and group B were 57.1% (8/14) and 70.0% (14/20), respectively. CONCLUSION: Taxotere is effective in the treatment of metastatic breast cancer. The toxic reactions are tolerable.