Development of a Mature B Lymphocyte Probe through Gating-Oriented Live-Cell Distinction (GOLD) and Selective Imaging of Topical Spleen

B lymphocytes play a pivotal role in the adaptive immune system by facilitating antibody production. Young B cell progenitors originate in the bone marrow and migrate to the spleen for antigen-dependent maturation, leading to the development of diverse B cell subtypes. Thus, tracking B cell trajectories through cell type distinction is essential for an appropriate checkpoint assessment. Despite its significance, monitoring specific B cell subclasses in live states has been hindered by a lack of suitable molecular tools. In this study, we introduce CDoB as the first mature B cell-selective probe, enabling real-time discrimination of three classified stages in B-cell development: progenitor, transitional, and mature B cells, through a single analysis using CyTOF. The selective mechanism of CDoB, elucidated as gating-oriented live-cell distinction (GOLD), targets SLC25A16, identified through systematic screening of SLC-CRISPRa and CRISPRi libraries. CDoB selectively brightens mature B cells in the mitochondrial area using SLC25A16 as the main gate, and the staining intensity correlates positively with the expression level of SLC25A16 along the B cell maturation continuum. In spleen tissues, CDoB demonstrates selective marking in mature B cell areas in live tissue status, representing the first performance achieved by a small-molecule fluorescent probe.

Discovery of Live Cell Selective Fluorescent Probes and Elucidation of Their Mechanisms: Case Study of B Cell Selective Probe CDgB

The development of small-molecule fluorescent probes for specific immune cell identification offers an economical alternative to expensive antibodies. Moreover, it enables the identification of live target cells and provides insights into the distinct properties of cells, leveraging their specific staining mechanisms. This chapter presents a comprehensive elucidation of the methodology employed for screening fluorescent compounds using flow cytometry measurements. A novel analytical approach is proposed to distinguish a fluorescent compound with a specific carbon length for B lymphocytes, involving an assessment of the staining index and the predominant ratio of immune cells. Moreover, a protocol is presented for investigating the staining mechanisms of these probes by employing cell mimicking models such as small unilamellar vesicles (SUVs).

Topological magnetic structure generation using VAE-GAN hybrid model and discriminator-driven latent sampling

Recently, deep generative models using machine intelligence are widely utilized to investigate scientific systems by generating scientific data. In this study, we experiment with a hybrid model of a variational autoencoder (VAE) and a generative adversarial network (GAN) to generate a variety of plausible two-dimensional magnetic topological structure data. Due to the topological properties in the system, numerous and diverse metastable magnetic structures exist, and energy and topological barriers separate them. Thus, generating a variety of plausible spin structures avoiding those barrier states is a challenging problem. The VAE-GAN hybrid model can present an effective approach to this problem because it brings the advantages of both VAE's diversity and GAN's fidelity. It allows one to perform various applications including searching a desired sample from a variety of valid samples. Additionally, we perform a discriminator-driven latent sampling (DDLS) using our hybrid model to improve the quality of generated samples. We confirm that DDLS generates various plausible data with large coverage, following the topological rules of the target system.

Super-resolution of magnetic systems using deep learning

We construct a deep neural network to enhance the resolution of spin structure images formed by spontaneous symmetry breaking in the magnetic systems. Through the deep neural network, an image is expanded to a super-resolution image and reduced to the original image size to be fitted with the input feed image. The network does not require ground truth images in the training process. Therefore, it can be applied when low-resolution images are provided as training datasets, while high-resolution images are not obtainable due to the intrinsic limitation of microscope techniques. To show the usefulness of the network, we train the network with two types of simulated magnetic structure images; one is from self-organized maze patterns made of chiral magnetic structures, and the other is from magnetic domains separated by walls that are topological defects of the system. The network successfully generates high-resolution images highly correlated with the exact solutions in both cases. To investigate the effectiveness and the differences between datasets, we study the network's noise tolerance and compare the networks' reliabilities. The network is applied with experimental data obtained by magneto-optical Kerr effect microscopy and spin-polarized low-energy electron microscopy.

A Photoinduced Electron Transfer-Based Hypochlorite-Specific Fluorescent Probe for Selective Imaging of Proinflammatory M1 in a Rheumatoid Arthritis Model

The differentiation of the distinct phenotypes of macrophages is essential for monitoring the stage of inflammatory diseases for accurate diagnosis and treatment. Recent studies revealed that the level of hypochlorite (OCl^-) varies from activated M1 macrophages (killing pathogens) to M2 (resolution of inflammation) during inflammation. Thus, we developed a simple and efficient fluorescent probe for discriminating M1 from M0 and M2. Herein, fluorescent-based imaging is applied as an alternative to immunohistochemistry, which is challenging due to the tedious process and high cost. We developed a hypochlorite-specific probe PMS-T to differentiate M1 and M2, employing a metabolism-oriented live-cell distinction. This probe enables the detection of inflammatory rheumatoid arthritis in an ex vivo mouse model. Thus, it can be a potential chemical tool for monitoring inflammatory diseases, including rheumatoid arthritis, that may overcome the existing barriers of immunohistochemistry.

Development of a Fluorescent Probe for M2 Macrophages via Gating-Oriented Live-Cell Distinction

Macrophages are the most plastic immune cells by changing their characters in response to environmental stimuli. Broadly, macrophages are categorized into two different subsets based on M1/M2 paradigm, which exhibit completely contrary phenotypes. Whereas M1 macrophages are aggressive to offend invaders such as bacteria and tumors, M2 are anti-inflammatory cells and seemingly help tumor immunity. Tumor-associated macrophages are typical examples of M2 cells as the key components of forming and maintaining the tumor microenvironment. Despite the intensive interest, monitoring M2 macrophages in real time is hampered by the lack of competent detection tools. Here, we report the first M2 selective probe CDg18 with a novel mechanism of gating-oriented live-cell distinction through M2-favored fatty acid transporters. To demonstrate the potential of CDg18, we visualize the progressive phenotypic change of M2 toward M1 using a resveratrol analogue HS-1793 as a reprogramming effector. Combined together with M1 probe CDr17, the diminishing M2 character and emerging M1 markers could be simultaneously monitored in real time through the multicolor changes during macrophage reprogramming.

A palette of site-specific organelle fluorescent thermometers

Intracellular micro-temperature is closely related to cellular processes. Such local temperature inside cells can be measured by fluorescent thermometers, which are a series of fluorescent materials that convert the temperature information to detectable fluorescence signals. To investigate the intracellular temperature fluctuation in various organelles, it is essential to develop site-specific organelle thermometers. In this study, we develop a new series of fluorescent thermometers, Thermo Greens (TGs), to visualize the temperature change in almost all typical organelles. Through fluorescence lifetime-based cell imaging, it was proven that TGs allow the organelle-specific monitoring of temperature gradients created by external heating. The fluorescence lifetime-based thermometry shows that each organelle experiences a distinct temperature increment which depends on the distance away from the heat source. TGs are further demonstrated in the quantitative imaging of heat production at different organelles such as mitochondria and endoplasmic reticulum in brown adipocytes. To date, TGs are the first palette batch of small molecular fluorescent thermometers that can cover almost all typical organelles. These findings can inspire the development of new fluorescent thermometers and enhance the understanding of thermal biology in the future.

Visualizing inflammation with an M1 macrophage selective probe via GLUT1 as the gating target

Macrophages play crucial roles in protecting our bodies from infection and cancers. As macrophages are multi-functional immune cells, they have diverse plastic subsets, such as M1 and M2, derived from naïve M0 cells. Subset-specific macrophage probes are essential for deciphering and monitoring the various activation of macrophages, but developing such probes has been challenging. Here we report a fluorescent probe, CDr17, which is selective for M1 macrophages over M2 or M0. The selective staining mechanism of CDr17 is explicated as Gating-Oriented Live-cell Distinction (GOLD) through overexpressed GLUT1 in M1 macrophages. Finally, we demonstrate the suitability of CDr17 to track M1 macrophages in vivo in a rheumatoid arthritis animal model.

Studying the specific roles of macrophage subsets has been hampered by a lack of subset-specific probes. Here the authors report an M1 selective fluorescent probe named CDr17, and demonstrate the suitability of this probe for tracking M1 macrophages in vivo.

A SLC35C2 Transporter-Targeting Fluorescent Probe for the Selective Detection of B Lymphocytes Identified by SLC-CRISPRi and Unbiased Fluorescence Library Screening

T and B lymphocytes are two major adaptive immune cells in the human defense system. To real-time monitor their diverse functions, a live-cell-selective probe for only one cell type is need to investigate the complex interaction of the immune cells. Herein, a small-molecule probe CDyB for live B cells is developed by an unbiased fluorescence library screening. The cell selectivity was confirmed by multiparametric single-cell analysis using CyTOF. Through a systematic SLC-CRISPRi library screening, the molecular target of CDyB was identified as SLC35C2 transporter based on a gating-oriented live-cell distinction (GOLD) mechanism. The gene expression analysis and knock-out experiments validated that the SLC35C2 transporter was the target for CDyB distinction. Interestingly, when CDyB was applied to study B cell development, the CDyB fluorescence and SLC35C2 expression were positively correlated with the B cell maturation process, and not involved in the T cell development.

Contagious Aggregation: Transmittable Protein Aggregation in Cellular Communities Initiated by Synthetic Cells

Aggregation of amyloidogenic proteins causing neurodegenerative diseases is an uncontrollable and contagious process that is often associated with lipid membranes in a highly complex physiological environment. Although several approaches using natural cells and membrane models have been reported, systematic investigations focusing on the association with the membranes are highly challenging, mostly because of the lack of proper molecular tools. Here, we report a new supramolecular approach using a synthetic cell system capable of controlling the initiation of protein aggregation and mimicking various conditions of lipid membranes, thereby enabling systematic investigations of membrane-dependent effects on protein aggregation by visualization. Extending this strategy through concurrent use of synthetic cells and natural cells, we demonstrate the potential of this approach for systematic and in-depth studies on interrogating inter- and intracellularly transmittable protein aggregation. Thus, this new approach offers opportunities for gaining insights into the pathological implications of contagious protein aggregation associated with membranes for neurotoxicity.

Target identification of mouse stem cell probe CDy1 as ALDH2 and Abcb1b through live-cell affinity-matrix and ABC CRISPRa library

CDy1 is a powerful tool to distingusih embryonic stem cells for reprogramming studies and regeneration medicine. However, the stem cell selectivity mechanism of CDy1 has not been fully understood. Here, we report ALDH2 and ABCB1 as the molecular targets of CDy1, elucidated by live-cell affinity-matrix and ABC transporter CRISPRa library screening. The two unique orthogonal mechanisms provide the potential of multi-demensional cellular distinction of specific cell types.

CDy1 is a powerful tool to distingusih embryonic stem cells for reprogramming studies and regeneration medicine.

Estimating the effective fields of spin configurations using a deep learning technique

The properties of complicated magnetic domain structures induced by various spin-spin interactions in magnetic systems have been extensively investigated in recent years. To understand the statistical and dynamic properties of complex magnetic structures, it is crucial to obtain information on the effective field distribution over the structure, which is not directly provided by magnetization. In this study, we use a deep learning technique to estimate the effective fields of spin configurations. We construct a deep neural network and train it with spin configuration datasets generated by Monte Carlo simulation. We show that the trained network can successfully estimate the magnetic effective field even though we do not offer explicit Hamiltonian parameter values. The estimated effective field information is highly applicable; it is utilized to reduce noise, correct defects in the magnetization data, generate spin configurations, estimate external field responses, and interpret experimental images.

Neutrophil-Selective Fluorescent Probe Development through Metabolism-Oriented Live-Cell Distinction

Human neutrophils are the most abundant leukocytes and have been considered as the first line of defence in the innate immune system. Selective imaging of live neutrophils will facilitate the in situ study of neutrophils in infection or inflammation events as well as clinical diagnosis. However, small-molecule-based probes for the discrimination of live neutrophils among different granulocytes in human blood have yet to be reported. Herein, we report the first fluorescent probe NeutropG for the specific distinction and imaging of active neutrophils. The selective staining mechanism of NeutropG is elucidated as metabolism-oriented live-cell distinction (MOLD) through lipid droplet biogenesis with the help of ACSL and DGAT. Finally, NeutropG is applied to accurately quantify neutrophil levels in fresh blood samples by showing a high correlation with the current clinical method.

Lipid-Oriented Live-Cell Distinction of B and T Lymphocytes

The identification of each cell type is essential for understanding multicellular communities. Antibodies set as biomarkers have been the main toolbox for cell-type recognition, and chemical probes are emerging surrogates. Herein we report the first small-molecule probe, CDgB, to discriminate B lymphocytes from T lymphocytes, which was previously impossible without the help of antibodies. Through the study of the origin of cell specificity, we discovered an unexpected novel mechanism of membrane-oriented live-cell distinction. B cells maintain higher flexibility in their cell membrane than T cells and accumulate the lipid-like probe CDgB more preferably. Because B and T cells share common ancestors, we tracked the cell membrane changes of the progenitor cells and disclosed the dynamic reorganization of the membrane properties over the lymphocyte differentiation progress. This study casts an orthogonal strategy for the small-molecule cell identifier and enriches the toolbox for live-cell distinction from complex cell communities.

Magnetic Hamiltonian parameter estimation using deep learning techniques

Understanding spin textures in magnetic systems is extremely important to the spintronics and it is vital to extrapolate the magnetic Hamiltonian parameters through the experimentally determined spin. It can provide a better complementary link between theories and experimental results. We demonstrate deep learning can quantify the magnetic Hamiltonian from magnetic domain images. To train the deep neural network, we generated domain configurations with Monte Carlo method. The errors from the estimations was analyzed with statistical methods and confirmed the network was successfully trained to relate the Hamiltonian parameters with magnetic structure characteristics. The network was applied to estimate experimentally observed domain images. The results are consistent with the reported results, which verifies the effectiveness of our methods. On the basis of our study, we anticipate that the deep learning techniques make a bridge to connect the experimental and theoretical approaches not only in magnetism but also throughout any scientific research.

Multimodal Imaging Probe Development for Pancreatic β Cells: From Fluorescence to PET

Pancreatic β cells are responsible for insulin secretion and are important for glucose regulation in a healthy body and diabetic disease patient without prelabeling of islets. While the conventional biomarkers for diabetes have been glucose and insulin concentrations in the blood, the direct determination of the pancreatic β cell mass would provide critical information for the disease status and progression. By combining fluorination and diversity-oriented fluorescence library strategy, we have developed a multimodal pancreatic β cell probe PiF for both fluorescence and for PET (positron emission tomography). By simple tail vein injection, PiF stains pancreatic β cells specifically and allows intraoperative fluorescent imaging of pancreatic islets. PiF-injected pancreatic tissue even facilitated an antibody-free islet analysis within 2 h, dramatically accelerating the day-long histological procedure without any fixing and dehydration step. Not only islets in the pancreas but also the low background of PiF in the liver allowed us to monitor the intraportal transplanted islets, which is the first in vivo visualization of transplanted human islets without a prelabeling of the islets. Finally, we could replace the built-in fluorine atom in PiF with radioactive 18F and successfully demonstrate in situ PET imaging for pancreatic islets.

An innovative magnetic state generator using machine learning techniques

We propose a new efficient algorithm to simulate magnetic structures numerically. It contains a generative model using a complex-valued neural network to generate k-space information. The output information is hermitized and transformed into real-space spin configurations through an inverse fast Fourier transform. The Adam version of stochastic gradient descent is used to minimize the magnetic energy, which is the cost of our algorithm. The algorithm provides the proper ground spin configurations with outstanding performance. In model cases, the algorithm was successfully applied to solve the spin configurations of magnetic chiral structures. The results also showed that a magnetic long-range order could be obtained regardless of the total simulation system size.

A Near-Infrared Probe Tracks and Treats Lung Tumor Initiating Cells by Targeting HMOX2

Tumor initiating cells (TIC) are resistant to conventional anticancer therapy and associated with metastasis and relapse in cancer. Although various TIC markers and their antibodies have been proposed, it is limited to the use of antibodies for in vivo imaging or treatment of TIC. In this study, we discovered heme oxygenase 2 (HMOX2) as a novel biomarker for TIC and developed a selective small molecule probe TiNIR (tumor initiating cell probe with near infrared). TiNIR detects and enriches the functionally active TIC in human lung tumors, and through the photoacoustic property, TiNIR also visualizes lung TIC in the patient-derived xenograft (PDX) model. Furthermore, we demonstrate that TiNIR inhibits tumor growth by blocking the function of HMOX2, resulting in significantly increased survival rates of the cancer model mice. The novel therapeutic target HMOX2 and its fluorescent ligand TiNIR will open a new path for the molecular level of lung TIC diagnosis and treatment.

Association of preoperative anemia and perioperative allogenic red blood cell transfusion with oncologic outcomes in patients with nonmetastatic colorectal cancer

Background

We investigated whether preoperative anemia and perioperative blood transfusion (pbt) are associated with overall survival and recurrence-free survival in patients with nonmetastatic colorectal cancer.

Methods

From 1 January 2009 to 31 December 2014, 1003 patients with primary colorectal cancer were enrolled in the study. Perioperative clinical and oncologic outcomes were analyzed based on the presence of preoperative anemia and pbt.

Results

Preoperative anemia was found in 468 patients (46.7%). In the anemia and no-anemia groups, pbt was performed in 44% and 15% of patients respectively. Independent predictors for pbt were preoperative anemia, higher American Society of Anesthesiologists score, laparotomy, lengthy operative time, advanced TNM stage, T4 stage, and 30-day morbidity. The use of pbt, but not preoperative anemia, was found to be an independent adverse prognostic factor for overall survival. In terms of recurrence-free survival, the presence of preoperative anemia was similarly not a significant prognostic factor, but the use of pbt was an independent factor for an unfavourable prognosis.

Conclusions

The use of pbt, but not preoperative anemia, was independently associated with worse overall and recurrence-free survival in nonmetastatic colorectal cancer. For better oncologic outcomes, our findings indicate a need to reduce the use of blood transfusion during the perioperative period.

Visualizing biofilm by targeting eDNA with long wavelength probe CDr15

We developed a small molecule CDr15, which has eDNA selectivity of bacterial biofilm.

The spin structures of interlayer coupled magnetic films with opposite chirality

Using Monte-Carlo simulations and micromagnetic simulations, we reveal how the spin structural correlation and the skyrmion dynamics are affected by the interlayer coupling in a chiral magnetic bilayer system, in which the two layers have opposite chirality. The interaction through interlayer coupling between chiral magnetic structures influences the static and dynamics properties profoundly. The competition between the Dzyaloshinskii-Moriya interaction and the interlayer interaction allows multiple magnetic structures to be energetically stable, which includes sole skyrmion states (skyrmion appears in only one of the layers) and skyrmion pair states (coupled skyrmions in top and bottom layers). When current driven spin transfer torques are applied to each state, the sole skyrmion state is mainly propelled by a spin transfer torque causing the skyrmion hall effect, but the skyrmion pair state is propelled by a torque from skyrmion-skyrmion interaction and not influenced by the skyrmion hall effect. Also upon application of an external magnetic field, we found the skyrmions in a skyrmion pair state extinguish in an exclusive way, as the annihilation of a skyrmion in one of the layers stabilizes the once paired skyrmion in the other layer, i.e. the skyrmion lattice sites have only one skyrmion in either layer.

CDy14: a novel biofilm probe targeting exopolysaccharide Psl

We developed CDy14, which is the first small molecule probe for Psl target in bacterial biofilm.

Photodynamic Approach for Teratoma-Free Pluripotent Stem Cell Therapy Using CDy1 and Visible Light

Pluripotent stem cells (PSC) are promising resources for regeneration therapy, but teratoma formation is one of the critical problems for safe clinical application. After differentiation, the precise detection and subsequent elimination of undifferentiated PSC is essential for teratoma-free stem cell therapy, but a practical procedure is yet to be developed. CDy1, a PSC specific fluorescent probe, was investigated for the generation of reactive oxygen species (ROS) and demonstrated to induce selective death of PSC upon visible light irradiation. Importantly, the CDy1 and/or light irradiation did not negatively affect differentiated endothelial cells. The photodynamic treatment of PSC with CDy1 and visible light irradiation confirmed the inhibition of teratoma formation in mice, and suggests a promising new approach to safe PSC-based cell therapy.

Impact of vitamin D, bisphosphonate, and combination therapy on bone mineral density in kidney transplant patients

BACKGROUND

Osteoporosis can develop and become aggravated in kidney transplant patients; however, the best preventive options for post-transplantation osteoporosis remain controversial.

METHODS

We retrospectively analyzed cohort of 182 renal transplant recipients of mean age 46.7 ± 12.1 years including 47.3% women. Seventy-three patients received neither vitamin D nor bisphosphonate after transplantation (group 1). The other patients were classified into the following 3 groups: calcium plus vitamin D (group 2; n = 40); bisphosphonate (group 3; n = 18); and both regimens (group 4; n = 51). Bone mineral density (BMD) was evaluated by dual-energy X-ray absorptiometry at baseline and at 1 year after transplantation.

RESULTS

At 1 year after transplantation, T-scores of the femoral neck and entire femur were significantly decreased in group 1 (-0.23 ± 0.65 [P = .004] and -0.21 ± 0.74 [P = .018], respectively), whereas the lumbar spine was significantly increased in group 4 (0.27 ± 0.79; P = .020). Post hoc analysis demonstrated that the delta T-score was significantly lower in group 1 than in group 4 (P = .009, 0.035, and 0.031 for lumbar spine, femoral neck, and entire femur, respectively). In a multivariate analysis adjusted by age, sex, body mass index, dialysis duration, diabetes, calcineurin inhibitors, estimated glomerular filtration rate, and persistent hyperparathyroidism, both group 2 and group 4 showed protective effects on BMD reduction (odds ratio [OR], 0.165; 95% confidence interval [CI] 0.032-0.845 [P = .031]; and OR, 0.169; 95% CI, 0.045-0.626 [P = .008]; respectively). However, group 3 did not show a protective effect (OR, 0.777; 95% CI, 0.198-3.054; P = .718), because their incidence of persistent hyperparathyroidism after transplantation was significantly higher (50.0%) than the other groups (P < .001). The incidence of bone fractures did not differ among the groups.

CONCLUSIONS

Combination therapy with vitamin D and bisphosphonate was the most effective regimen to improve BMD among kidney recipients.

Triptolide induces apoptosis through extrinsic and intrinsic pathways in human osteosarcoma U2OS cells

Triptolide, a diterpene derived from Tripterygium wilfordii Hook f., a Chinese medicinal herb, has been reported to inhibit cell proliferation and induce apoptosis in various human cancer cells, but its anticancer effects on human osteosarcoma cells have not yet been elucidated. In this study, we investigated whether triptolide induces apoptosis in human osteosarcoma cells and the underlying molecular mechanisms. We firstly demonstrated that triptolide inhibited cell growth and induced apoptosis in U2OS cells. Western blot analysis showed that the levels of procaspase-8, -9, Bcl-2, Bid and mitochondrial cytochrome c were downregulated in triptolide-treated U2OS cells, whereas the levels of Fas, FasL, Bax, cytosolic cytochrome c, cleaved caspase-3 and cleaved PARP were upregulated. These results suggest that triptolide induces apoptosis in U2OS cells by activating both death receptor and mitochondrial apoptotic pathways.

Novel chiral magnetic domain wall structure in Fe/Ni/Cu(001) films

Using spin-polarized low energy electron microscopy, we discovered a new type of domain wall structure in perpendicularly magnetized Fe/Ni bilayers grown epitaxially on Cu(100). Specifically, we observed unexpected Néel-type walls with fixed chirality in the magnetic stripe phase. Furthermore, we find that the chirality of the domain walls is determined by the film growth order with the chirality being right handed in Fe/Ni bilayers and left handed in Ni/Fe bilayers, suggesting that the underlying mechanism is the Dzyaloshinskii-Moriya interaction at the film interfaces. Our observations may open a new route to control chiral spin structures using interfacial engineering in transition metal heterostructures.

Cordycepin induces apoptosis in human neuroblastoma SK-N-BE(2)-C and melanoma SK-MEL-2 cells

In this study, the effect of cordycepin (3'-deoxyadenosine), a major component of Cordyceps militaris, an ingredient of traditional Chinese medicine was investigated for the first time on apoptotsis in human neuroblastoma SK-N-BE(2)-C and melanoma SK-MEL-2 cells. Cordycepin significantly inhibited the proliferation of human neuroblastoma SK-N-BE(2)-C and human melanoma SK-MEL-2 cells with IC50 values of 120 microM and 80 microM, respectively. Cordycepin treatment at 120 microM and 80 microM, respectively, induced apoptosis in both cells and caused the increase of cell accumulation in a time-dependent manner at the apoptotic sub-G1 phase, as evidenced by the flow cytometry (FCM) and annexin V-fluorescein isothiocyanate (FITC) analyses. Western blot analysis revealed the induction of active caspase-3 and poly(ADP-ribose)polymerase (PARP) cleavage by cordycepin treatment. These results suggest that cordycepin is a potential candidate for cancer therapy of neuroblastoma and melanoma.

Transcriptional activation of human GM3 synthase (hST3Gal V) gene by valproic acid in ARPE-19 human retinal pigment epithelial cells

The present study demonstrated that valproic acid (VPA) transcriptionally regulates human GM3 synthase (hST3Gal V), which catalyzes ganglioside GM3 biosynthesis in ARPE-19 human retinal pigment epithelial cells. For this, we characterized the promoter region of the hST3Gal V gene. Functional analysis of the 5'-flanking region of the hST3Gal V gene revealed that the -177 to -83 region functions as the VPA-inducible promoter and that the CREB/ATF binding site at -143 is crucial for VPA-induced expression of hST3Gal V in ARPE-19 cells. In addition, the transcriptional activity of hST3Gal V induced by VPA in ARPE-19 cells was inhibited by SP600125, a c-Jun N-terminal kinase (JNK) inhibitor. In summary, our results identified the core promoter region in the hST3Gal V promoter and for the first time demonstrated that ATF2 binding to the CREB/ATF binding site at -143 is essential for transcriptional activation of hST3Gal V in VPA-induced ARPE-19 cells.

Triptolide downregulates human GD3 synthase (hST8Sia I) gene expression in SK-MEL-2 human melanoma cells

In this study, we have shown that gene expression of human GD3 synthase (hST8Sia I) is suppressed by triptolide (TPL) in human melanoma SK-MEL-2 cells. To elucidate the mechanism underlying the downregulation of hST8Sia I gene expression in TPL-treated SK-MEL-2 cells, we characterized the TPL-inducible promoter region within the hST8Sia I gene using luciferase constructs carrying 5'-deletions of the hST8Sia I promoter. Functional analysis of the 5'-flanking region of the hST8Sia I gene demonstrated that the -1146 to -646 region, which contains putative binding sites for transcription factors c-Ets-1, CREB, AP-1 and NF-κB, functions as the TPL-inducible promoter of hST8Sia I in SK-MEL-2 cells. Site-directed mutagenesis and ChIP analysis indicated that the NF-κB binding site at -731 to -722 is crucial for TPL-induced suppression of hST8Sia I in SK-MEL-2 cells. This suggests that TPL induces down-regulation of hST8Sia I gene expression through NF-κB activation in human melanoma cells.

Isolation and functional analysis of the human glioblastoma-specific promoter region of the human GD3 synthase (hST8Sia I) gene

We identified the promoter region of the human GD3 synthase (hST8Sia I) gene to elucidate the mechanism underlying the regulation of hST8Sia I expression in human glioblastoma cells. The 5'-rapid amplification of cDNA end using mRNA prepared from U-87MG cells revealed the presence of transcription start site of hST8Sia I gene, and the 5'-terminal analysis of its product showed that transcription started from 648 nucleotides upstream of the translational initiation site. Functional analysis of the 5'-flanking region of the hST8Sia I gene by transient expression method revealed that the region from -638 to -498 is important for transcriptional activity of the hST8Sia I gene in U-87MG and T98G cells. This region lacks apparent TATA and CAAT boxes, but contains putative binding sites for transcription factors AREB6 and Elk-1. Site-directed mutagenesis and transient transfection assays demonstrated that both AREB6 and Elk-1 elements in this region were required for the promoter activity in U-87MG and T98G cells. These results indicated that both AREB6 and Elk-1 might play an essential role in the transcriptional activity of hST8Sia I gene essential for GD3 synthesis in human glioblastoma cells.

Valproic acid induces transcriptional activation of human GD3 synthase (hST8Sia I) in SK-N-BE(2)-C human neuroblastoma cells

In this study, we have shown the transcriptional regulation of the human GD3 synthase (hST8Sia I) induced by valproic acid (VPA) in human neuroblastoma SK-N-BE(2)-C cells. To elucidate the mechanism underlying the regulation of hST8Sia I gene expression in VPA-stimulated SK-N-BE(2)-C cells, we characterized the promoter region of the hST8Sia I gene. Functional analysis of the 5'-flanking region of the hST8Sia I gene by the transient expression method showed that the -1146 to -646 region, which contains putative binding sites for transcription factors c-Ets-1, CREB, AP-1 and NF-kappaB, functions as the VPA-inducible promoter of hST8Sia I in SK-N-BE(2)-C cells. Site-directed mutagenesis and electrophoretic mobility shift assay indicated that the NF-kappaB binding site at -731 to -722 was crucial for the VPA-induced expression of hST8Sia I in SK-N-BE(2)-C cells. In addition, the transcriptional activity of hST8Sia I induced by VPA in SK-N-BE(2)-C cells was strongly inhibited by SP600125, which is a c-Jun N-terminal kinase (JNK) inhibitor, and GO6976, which is a protein kinase C (PKC) inhibitor, as determined by RT-PCR (reverse transcription-polymerase chain reaction) and luciferase assays. These results suggest that VPA markedly modulated transcriptional regulation of hST8Sia I gene expression through PKC/JNK signal pathways in SK-N-BE(2)-C cells.

Transduction of human catalase mediated by an HIV-1 TAT protein basic domain and arginine-rich peptides into mammalian cells

Antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) have been considered to have a beneficial effect against various diseases mediated by reactive oxygen species (ROS). Although a variety of modified recombinant antioxidant enzymes have been generated to protect against the oxidative stresses, the lack of their transduction ability into cells resulted in limited ability to detoxify intracellular ROS. To render the catalase enzyme capable of detoxifying intracellular ROS when added extracellularly, cell-permeable recombinant catalase proteins were generated. A human liver catalase gene was cloned and fused with a gene fragment encoding the HIV-1 Tat protein transduction domain (RKKRRQRRR) and arginine-rich peptides (RRRRRRRRR) in a bacterial expression vector to produce genetic in-frame Tat-CAT and 9Arg-CAT fusion proteins, respectively. The expressed and purified fusion proteins can be transduced into mammalian cells (HeLa and PC12 cells) in a time- and dose-dependent manner when added exogenously in culture medium, and transduced fusion proteins were enzymatically active and stable for 60 h. When exposed to H(2)O(2), the viability of HeLa cells transduced with Tat-CAT or 9Arg-CAT fusion proteins was significantly increased. In combination with transduced SOD, transduced catalase also resulted in a cooperative increase in cell viability when the cells were treated with paraquat, an intracellular antioxide anion generator. We then evaluated the ability of the catalase fusion proteins to transduce into animal skin. This analysis showed that Tat-CAT and 9Arg-CAT fusion proteins efficiently penetrated the epidermis as well as the dermis of the subcutaneous layer when sprayed on animal skin, as judged by immunohistochemistry and specific enzyme activities. These results suggest that Tat-CAT and 9Arg-CAT fusion proteins can be used in protein therapy for various disorders related to this antioxidant enzyme.

Oxidative modification of human ceruloplasmin by peroxyl radicals

Ceruloplasmin (CP), the blue oxidase present in all vertebrates, is the major copper-containing protein of plasma. We investigated oxidative modification of human CP by peroxyl radicals generated in a solution containing 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH). When CP was incubated with AAPH, the aggregation of proteins was increased in a time- and dose-dependent manner. Incubation of CP with AAPH resulted in a loss of ferroxidase activity. Superoxide dismutase and catalase did not protect the aggregation of CP, whereas hydroxyl radical scavengers such as ethanol and mannitol protected the protein aggregation. The aggregation of proteins was significantly inhibited by the copper chelators, diethyldithiocarbamate and penicillamine. Exposure of CP to AAPH led to the release of copper ions from the enzyme and the generation of protein carbonyl derivatives. Subsequently, when the amino acid composition of CP reacted with AAPH was analyzed, cysteine, tryptophan, methionine, histidine, tyrosine, and lysine residues were particularly sensitive.

The changes in the expressions of gamma-aminobutyric acid transporters in the gerbil hippocampal complex following spontaneous seizure

To identify the roles of gamma-aminobutyric acid (GABA) transporter in epileptogenesis and the recovery mechanisms in spontaneous seizure, a chronological and comparative analysis of GABA transporters (GAT) expression was conducted. GAT-1 immunoreactivity was more strongly detected in the pre-seizure group of seizure sensitive (SS) gerbils than that seen in the seizure resistant group. 30 min postictal, the density of GAT-1 immunoreactivity was significantly decreased in the hippocampal complex, as compared to pre-seizure group. 12 h after seizure on-set, the GAT immunodensity recovered to the pre-seizure level. Following the onset of seizure, GAT-3 immunoreactivity remained unchanged. These results suggest that the increase of GAT-1 expression in the SS gerbil hippocampus may affect epileptogenesis in this animal, and the alteration of immunoreactivity following seizure may be compensatory responses to modulate seizure activity.

Suppression of collagen-induced arthritis with histone H1

Besides roles in nucleus mediating the condensation of DNA into chromatin, the involvement of histones in autoimmune diseases, hormone regulation, and killing leukemia cells has been reported. In order to investigate the functions of histones on an autoimmune disease, histone H1 was injected into collagen-induced arthritis (CIA) mice. A dramatic suppression of CIA by histone H1 was observed at a dose of 1 mg/kg bodyweight of mouse. In addition, the increased level of anti-inflammatory cytokine IL-10 was detected in cultured splenocytes from the mouse treated with histone H1. These findings suggest that histone H1 suppresses the collagen-induced arthritis, possibly by increasing the level of IL-10 production.

Comparison of diameter and perimeter methods for tumor volume calculation

PURPOSE

Lesion volume is often used as an end point in clinical trials of oncology therapy. We sought to compare the common method of using orthogonal diameters to estimate lesion volume (the diameter method) with a computer-assisted planimetric technique (the perimeter method).

METHODS

Radiologists reviewed 825 magnetic resonance imaging studies from 219 patients with glioblastoma multiforme. Each study had lesion volume independently estimated via the diameter and perimeter methods. Cystic areas were subtracted out or excluded from the outlined lesion. Inter- and intrareader variability was measured by using multiple readings on 48 cases. Where serial studies were available in noncystic cases, a mock response analysis was used.

RESULTS

The perimeter method had a reduced interreader and intrareader variability compared with the diameter method (using SD of differences): intrareader, 1.76 mL v 7.38 mL (P < .001); interreader, 2.51 mL v 9.07 mL (P < .001) for perimeter and diameter results, respectively. Of the 121 noncystic cases, 23 had serial data. In six (26.1%) of those 23, a classification difference occurred when the perimeter method was used versus the diameter method.

CONCLUSION

Variability of measurements was reduced with the computer-assisted perimeter method compared with the diameter method, which suggests that changes in volume can be detected more accurately with the perimeter method. The differences between these techniques seem large enough to have an impact on grading the response to therapy.

The mouse Ames waltzer hearing-loss mutant is caused by mutation of Pcdh15, a novel protocadherin gene

The neuroepithelia of the inner ear contain hair cells that function as mechanoreceptors to transduce sound and motion signals. Mutations affecting these neuroepithelia cause deafness and vestibular dysfuction in humans. Ames waltzer (av) is a recessive mutation found in mice that causes deafness and a balance disorder associated with the degeneration of inner ear neuroepithelia. Here we report that the gene that harbours the av mutation encodes a novel protocadherin. Cochlear hair cells in the av mutants show abnormal stereocilia by 10 days after birth (P10). This is the first evidence for the requirement of a protocadherin for normal function of the mammalian inner ear.

Oxidative modification and inactivation of Cu,Zn-superoxide dismutase by 2,2'-azobis(2-amidinopropane) dihydrochloride

We have investigated oxidative modification of human Cu, Zn-superoxide dismutase (SOD) by alkylperoxyl radicals and alkylperoxides. To generate free radicals, we used the hydrophilic azocompound, 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH). When Cu,Zn-SOD was incubated with AAPH, the enzyme activity was decreased gradually in a time-dependent manner. The oxidative damage to Cu,Zn-SOD by AAPH-derived radicals led to protein fragmentation which is associated with the inactivation of enzyme. Incubation with AAPH resulted in the release of copper ions from Cu,Zn-SOD and the generation of protein carbonyl derivatives. Catalase did not protect the fragmentation of Cu,Zn-SOD whereas azide, glutathione and a metal chelator, diethylenetriamine pentaacetic acid inhibited the protein fragmentation. When Cu,Zn-SOD that has been exposed to AAPH was subsequently analyzed by amino acid analysis, lysine, histidine, proline, and valine residues were particularly sensitive. It is suggested that oxidative damage of Cu,Zn-SOD by AAPH-derived radicals may induce the perturbation of cellular antioxidant defense systems and subsequently lead to the deleterious condition in cells.

Transduction of Cu,Zn-superoxide dismutase mediated by an HIV-1 Tat protein basic domain into mammalian cells

A human Cu,Zn-superoxide dismutase (Cu,Zn-SOD) gene was fused with a gene fragment encoding the nine amino acid transactivator of transcription (Tat) protein transduction domain (RKKRRQRRR) of HIV-1 in a bacterial expression vector to produce a genetic in-frame Tat-SOD fusion protein. The expressed and purified Tat-SOD fusion protein in Escherichia coli can enter HeLa cells in a time- and dose-dependent manner when added exogenously in a culture media. Denatured Tat-SOD protein was transduced much more efficiently into cells than were native proteins. Once inside the cells, transduced Tat-SOD protein was enzymatically active and stable for 24 h. The cell viability of HeLa cells treated with paraquat, an intracellular superoxide anion generator, was increased by transduced Tat-SOD. These lines of results suggest that the transduction of Tat-SOD fusion protein may be one of the ways to replenish the Cu,Zn-SOD in the various disorders related to this antioxidant enzyme.

Role of GRPergic neurons in secretin-evoked exocrine secretion in isolated rat pancreas

Effects of intrapancreatic gastrin-releasing peptide (GRP)-containing neurons on secretin-induced pancreatic secretion were investigated in the totally isolated perfused rat pancreas. Electrical field stimulation (EFS) increased secretin (12 pM)-induced pancreatic secretions of fluid and amylase. EFS induced a twofold increase in GRP concentration in portal effluent, which was completely inhibited by tetrodotoxin but not modified by atropine. An anti-GRP antiserum inhibited the EFS-enhanced secretin-induced secretions of fluid and amylase by 12 and 43%, respectively, whereas a simultaneous infusion of the antiserum and atropine completely abolished them. Exogenous GRP dose-dependently increased the secretin-induced pancreatic secretion with an additive effect on fluid secretion and a potentiating effect on amylase secretion, which was not affected by atropine. In conclusion, excitation by EFS of GRPergic neurons in the isolated rat pancreas results in the release of GRP, which exerts an additive effect on fluid secretion and a potentiating effect on amylase secretion stimulated by secretin. The release and action of GRP in the rat pancreas are independent of cholinergic tone.

Fragmentation of human ceruloplasmin induced by hydrogen peroxide

We investigated the fragmentation of human ceruloplasmin induced by H2O2 to study its oxidative damage. When ceruloplasmin was incubated with H2O2, the frequency of the protein fragmentation increased in a proportion to the concentration of H2O2. It also increased in a time-dependent manner and was accompanied by gradual loss of the oxidase activity. Hydroxyl radical scavengers such as azide and mannitol inhibited the fragmentation of ceruloplasmin. The deoxyribose assay showed that hydroxyl radicals were generated in the reaction of ceruloplasmin with H2O2. Incubation of ceruloplasmin with H2O2 resulted in a time-dependent release of copper ions. The released copper ion may participate in a Fenton-like reaction to produce hydroxyl radical, which enhanced the fragmentation. The protection of the fragmentation by copper chelators such as diethylenetriaminepentaacetic acid and bathocuproine indicates a role for copper ion in the reaction. These results suggest that the fragmentation of ceruloplasmin induced by H2O2 is due to hydroxyl radicals formed by a copper-dependent Fenton-like reaction.

Hydrogen peroxide-mediated Cu,Zn-superoxide dismutase fragmentation: protection by carnosine, homocarnosine and anserine

The fragmentation of human Cu,Zn-superoxide dismutase (SOD) was observed during incubation with H(2)O(2). Hydroxyl radical scavengers such as sodium azide, formate and mannitol protected the fragmentation of Cu,Zn-SOD. These results suggested that *OH was implicated in the hydrogen peroxide-mediated Cu,Zn-SOD fragmentation. Carnosine, homocarnosine and anserine have been proposed to act as anti-oxidants in vivo. We investigated whether three compounds could protect the fragmentation of Cu,Zn-SOD induced by H(2)O(2). The results showed that carnosine, homocarnosine and anserine significantly protected the fragmentation of Cu,Zn-SOD. All three compounds also protected the loss of enzyme activity induced by H(2)O(2). Carnosine, homocarnosine and anserine effectively inhibited the formation of *OH by the Cu,Zn-SOD/H(2)O(2) system. These results suggest that carnosine and related compounds can protect the hydrogen peroxide-mediated Cu,Zn-SOD fragmentation through the scavenging of *OH.

The role of growth factor on regeneration of nitric oxide synthase (NOS)--containing nerves after cavernous neurotomy in the rats

Nitric oxide synthase (NOS) containing nerve regeneration can be seen six months after unilateral cavernous nerve neurotomy in rats. However, its molecular mechanism is still unknown. It is believed that growth factors are involved in this phenomenon. In this study we investigated the change of NOS containing nerve fibers and the RNA expression of insulin like growth factor (IGF)-I, nerve growth factor (NGF), transforming growth factor (TGF)-alpha, TGF-beta 1, TGF-beta 2. TGF-beta 3 and NOS on the penis after cavernous nerve neurotomy in rats. Male rats were divided into three groups: (1) sham operation (N = 10); (2) unilateral neurotomy of a 5 mm segment of the cavernous nerve (N = 15); and (3) bilateral neurotomy (n = 15). Electrostimulation of the intact cavernous nerve or pelvic ganglion was performed at one, three and six months. Nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase staining was used to identify NOS in the penile nerve fibers. The gene expression for growth factors and bNOS was investigated in corporal tissue by reverse transcriptase-polymerase chain reaction (RT-PCR) using specific oligonucleotide primers. One month after neurotomy, both unilateral and bilateral neurotomy groups showed a significant decrease in NOS-containing nerve fibers on the dorsal and intracavernosal nerves on the side of neurotomy, and a significantly lower mRNA expression of bNOS, IGF-I and TGF-beta 2. At three months, the number of NOS-containing nerve fibers in the unilateral neurotomy group increased only slightly but at six months those in the intracavernosal nerve increased in a significant amount (P < 0.0001), however mRNA expression of bNOS, IGF-I and TGF-beta 2 showed a significant increase as early as at three months. After bilateral neurotomy, the NOS-positive nerve fibers in the dorsal and intracavernosal nerve were significantly decreased at one month and remained so at six months; no erectile response could be elicited by pelvic ganglion stimulation. In the unilateral neurotomy group at six months, more NOS-positive neurons in the pelvic ganglia were found on the intact side than on the side of the neurotomy (P < 0.003), indicating that the regeneration derives from pelvic ganglion neurons on the intact side. Furthermore, electrostimulation in the unilateral neurotomy group revealed a greater maximal intracavernosal pressure and a shorter latency period at six months than at one month (P < 0.014, P < 0.001, respectively). These data suggest that IGF-I and TGF-beta 2 may play a key role in regeneration of NOS-containing nerve fibers in the dorsal and intracavernosal nerves after unilateral cavernous nerve injury.