LILRB2 inhibition enhances radiation sensitivity in non-small cell lung cancer by attenuating radiation-induced senescence.

Radiotherapy (RT) in non-small cell lung cancer (NSCLC) triggers cellular senescence, complicating tumor microenvironments and affecting treatment outcomes. This study examines the role of lymphocyte immunoglobulin-like receptor B2 (LILRB2) in modulating RT-induced senescence and radiosensitivity in NSCLC. Through methodologies including irradiation, lentivirus transfection, and various molecular assays, we assessed LILRB2's expression and its impact on cellular senescence levels and tumor cell behaviors. Our findings reveal that RT upregulates LILRB2, facilitating senescence and a senescence-associated secretory phenotype (SASP), which in turn enhances tumor proliferation and resistance to radiation. Importantly, LILRB2 silencing attenuates these effects by inhibiting the JAK2/STAT3 pathway, significantly increasing radiosensitivity in NSCLC models. Clinical data correlate high LILRB2 expression with reduced RT response and poorer prognosis, suggesting LILRB2's pivotal role in RT-induced senescence and its potential as a therapeutic target to improve NSCLC radiosensitivity.

Exposure to trace levels of live seaweed-derived antibacterial 2,4,6-tribromophenol modulates ß-lactam antibiotics resistance in Vibrio.

Non-antibiotic substances have been found to contribute to the spread of antibiotic resistance. Bromophenols (BPs) are special anti-bacterial substances obtained from seaweed. This study explored the modulatory effect of trace BPs from a live seaweed on the antibiotic resistance of pathogenic Vibrio (V.) strains. A hydroponic solution of Ulva fasciata was found to contain trace levels (9-333 µg L-1) of 2,4,6-tribromophenol (TBP), a typical BP. TBP at a concentration of 165 µg L-1 significantly increased the inhibition zone diameter of widely used ß-lactam antibiotics (amoxicillin and ampicillin) against V. alginolyticus M7 (Va. M7) and V. parahaemolyticus M3 (Vp. M3) as well as reduced the minimum inhibitory concentration by 2-4 fold against Va. M7. Whole genome re-sequencing analysis demonstrated that Va. M3 (53-60) had more mutant genes than Vp. M7 (44) in ß-lactam resistance pathway. Transcriptome sequencing analysis, along with verification through RT-qPCR, further showed that oligopeptide permease (opp) was the only differentially expressed gene (DEG) among the mutated genes in the ß-lactam resistance pathway. The opp transport activity and membrane permeability of Vibrio were both enhanced at 165 µg L-1 of TBP, and the ability of biofilm formation was also decreased. Thus, antibiotics resistance improvement of Vibrio by TBP was potentially related with the promoted opp transport activity, membrane permeability and inhibited biofilm formation.

Inhibition of CDC20 potentiates anti-tumor immunity through facilitating GSDME-mediated pyroptosis in prostate cancer.

BACKGROUND: Increasing evidence suggests that immunotherapy, especially immune checkpoint inhibitors (ICIs), has the potential to facilitate long-term survival in various cancer besides prostate cancer. Emerging evidence indicated that pyroptosis, an immunogenic form of cell death, could trigger an anti-tumor immune microenvironment and enhance the effectiveness of immunotherapy. Nevertheless, the mechanism underlying the regulation of pyroptosis signaling in prostate cancer remains unclear. METHODS: The differential expression of human E3 ligases in prostate cancer was integratedly analyzed from five independent public datasets. Moreover, the immunohistochemistry analysis of a tissue microarray derived from prostate cancer patients confirmed the results from the bioinformatic analysis. Furthermore, prostate cancer cell lines were evaluated via the next-generation RNA sequencing to assess transcriptomic profile upon CDC20 depletion. Next, qRT-PCR, Western blotting, cycloheximide assay, immunoprecipitation, and ubiquitination assay were employed to explore the correlation and interaction between CDC20 and GSDME. Both immune-deficient and immune-competent murine models were utilized to examine the anti-tumor efficacy of CDC20 inhibition with or without the anti-PD1 antibodies, respectively. To analyze the immune microenvironment of the xenografts, the tumor tissues were examined by immunohistochemistry and flow cytometry. RESULTS: The analysis of multiple prostate cancer cohorts suggested that CDC20 was the most significantly over-expressed E3 ligase. In addition, CDC20 exerted a negative regulatory effect on the pyroptosis pathway by targeting GSDME for ubiquitination-mediated proteolysis in a degron-dependent manner. Knockdown of CDC20 leads to increased GSDME abundance and a transition from apoptosis to pyroptosis in response to death signals. Furthermore, in our syngeneic murine models, we found that depletion of CDC20 significantly enhances the anti-tumor immunity by promoting the infiltration of CD8+ T lymphocytes dependent on the existence of GSDME, as well as reducing myeloid immune cells. More importantly, Apcin, a small molecular inhibitor that targets CDC20, exhibited synergistic effects with anti-PD1-based immunotherapy in murine models of prostate cancer. CONCLUSIONS: Overall, these findings provide new insights into the upstream regulation of GSDME-mediated pyroptosis by CDC20, which specifically interacts with GSDME and facilitates its ubiquitination in a degron-dependent manner. Importantly, our data highlight novel molecular pathways for targeting cellular pyroptosis and enhancing the effectiveness of anti-PD1-based immunotherapy.

LRAF-Net: Long-Range Attention Fusion Network for Visible-Infrared Object Detection.

Visible-infrared object detection aims to improve the detector performance by fusing the complementarity of visible and infrared images. However, most existing methods only use local intramodality information to enhance the feature representation while ignoring the efficient latent interaction of long-range dependence between different modalities, which leads to unsatisfactory detection performance under complex scenes. To solve these problems, we propose a feature-enhanced long-range attention fusion network (LRAF-Net), which improves detection performance by fusing the long-range dependence of the enhanced visible and infrared features. First, a two-stream CSPDarknet53 network is used to extract the deep features from visible and infrared images, in which a novel data augmentation (DA) method is designed to reduce the bias toward a single modality through asymmetric complementary masks. Then, we propose a cross-feature enhancement (CFE) module to improve the intramodality feature representation by exploiting the discrepancy between visible and infrared images. Next, we propose a long-range dependence fusion (LDF) module to fuse the enhanced features by associating the positional encoding of multimodality features. Finally, the fused features are fed into a detection head to obtain the final detection results. Experiments on several public datasets, i.e., VEDAI, FLIR, and LLVIP, show that the proposed method obtains state-of-the-art performance compared with other methods.

Antibiotics resistance evolution of isolated Vibrio parahaemolyticus from mariculture under the continuous culture of sub-inhibitory concentrations of Ulva fasciata hydroponic solution.

The outbreak of vibriosis from Vibrio (V.) parahaemolyticus is widespread in the mariculture, and live macroalgae has been considered to be effective and eco-friendly approach for the control of vibriosis. Three V. parahaemolyticus strains with ß-lactam antibiotics resistance (resistant to ampicillin (AM), amoxicillin (AMX)) were isolated from mariculture in study, and the antibiotics resistance evolution mechanism was examined at the sub-inhibitory concentration (SIC) of hydroponic solution of Ulva (U.) fasciata (HSUF). The HSUF with the highest density (20 g fresh weight U. fasciata L-1) demonstrated the strongest inhibitory rates (47.0 %-65.8 %) on the three strains during the stable phase (8-24 h) of growth curve, which indicated that the HSUF (≤20 g L-1) could be considered to be at SIC for V. parahaemolyticus strains. After continuous subculture of V. parahaemolyticus with three dilutes (1/2 (HT), 1/20 (MT) and 1/50 (LT)) of HSUF (20 g L-1), all the strains of 20th generation were still resistant to AM and AMX. However, the LT condition reduced MIC of AM (2-16 times) and AMX (0-2 times) to strains, while MT and HT showed significantly various effect of ß-lactam antibiotics resistance on different strains. The biofilm formation and ROS content of V. parahaemolyticus were almost positively correlated to the concentrations of HSUF. Transcriptome sequencing analysis of a representative strain showed that the lower concentrations of HSUF caused more down-regulated DEGs of the strains, and more down-regulated (vmeA, vmeB, sapA, mrdA) DEGs of strains were related to the pathway of ß-lactam antibiotics resistance at LT condition. Thus, low concentration of HSUF was seemed to have better improvement for V. parahaemolyticus strains resistant to ß-lactam antibiotics, which were mainly related to the impairment of biofilm formation, ROS and efflux pump.

The fate of antibiotic resistance genes, microbial community, and potential pathogens in the maricultural sediment by live seaweeds and oxytetracycline.

Three common seaweeds including Ulva fasciata, Codium cylindricum and Ishige okamurai were used for the remediation of maricultural wastewater and sediment in the presence/absence of trace level of oxytetracycline (OTC) in lab-scale experiments. Higher NO3--N and PO43--P removal rates were achieved due to the presence of seaweeds, and trace OTC also had a positive effect on NO3--N removal. A slight variation of 2.10-2.15% were observed in the total relative abundances of antibiotic resistance genes (ARGs) of different sediment samples after one-month operation. However, the variation of ARGs profiles by the co-existence of different seaweeds and OTC was in the descending order of Ishige okamurai > Codium cylindricum > Ulva fasciata, which was in accordance with the variation of microbial hosts at genus level. The abundance of dominant tetracycline resistance genes promoted by the co-existence of different seaweeds and OTC in compared with the presence of single seaweed or OTC via metagenomic sequencing and qPCR analysis, and the co-existence of Ishige okamurai and OTC exhibited the largest impact. The potential pathogens were more sensitive to the co-existence of seaweed and OTC than single seaweeds. Meanwhile, a variety of ARGs were enriched in the pathogens, and the dominant pathogenic bacteria of Vibrio had 133 Vibrio species with 28 subtypes of ARGs. The variation of ARGs profiles in the sediment were strongly related with the dominant phyla Proteobacteria, Actinobacteria, Firmicutes, Planctomycetes and Cyanobacteria. Besides, Nitrate level exhibited more significant effect on ∑ARGs, ARGs resistant to vancomycin and streptogramin_a, while phosphate level exhibited more positively significant effect on ARGs resistant to fosmidomycin, ATFBT and cephalosporin.

Accurate feature point detection method exploiting the line structure of the projection pattern for 3D reconstruction.

The 3D imaging methods using a grid pattern can satisfy real-time applications since they are fast and accurate in decoding and capable of producing a dense 3D map. However, like the other spatial coding methods, it is difficult to achieve high accuracy as is the case for time multiplexing due to the effects of the inhomogeneity of the scene. To overcome those challenges, this paper proposes a convolutional-neural-network-based method of feature point detection by exploiting the line structure of the grid pattern projected. First, two specific data sets are designed to train the model to individually extract the vertical and horizontal stripes in the image of a deformed pattern. Then the predicted results of trained models with images from the test set are fused in a unique skeleton image for the purpose of detecting feature points. Our experimental results show that the proposed method can achieve higher location accuracy in feature point detection compared with previous ones.

Automatic Coregistration Between Coronary Angiography and Intravascular Optical Coherence Tomography: Feasibility and Accuracy.

This study sought to evaluate a novel approach for automatic coregistration of optical coherence tomography (OCT) and coronary angiography. Lumen diameters and side branches from both coronary angiography and OCT were used to create 2 feature sets. Subsequently, a 2-step coregistration approach was performed on the feature sets for matching of each OCT cross section on the angiographic centerline. For validation, all side branches with ≥1.0 mm diameter were identified and used as paired fiduciary landmarks. Geographical error was defined as the distance between the automatically coregistered and the true-paired landmarks. Altogether 212 vessels from 181 patients were analyzed. Mismatch of coronary angiography and OCT occurred in 64 of 1,530 reference landmarks. Median geographical error was 0.32 (interquartile range: 0.00-0.56) mm. The mean time for coregistration was 20.69 ± 1.07 seconds. In conclusion, fast and automatic coregistration of OCT and angiography using a single standard angiographic loop is feasible and accurate.

Long non­coding RNA RP11­400N13.3 promotes the progression of colorectal cancer by regulating the miR­4722­3p/P2RY8 axis.

Accumulating evidence has shown that long non­coding RNAs (lncRNAs) play significant roles in the development and progression of many types of cancer including colorectal cancer. RP11­400N13.3 is a novel lncRNA discovered recently and its biological function and underlying mechanism in colorectal cancer remain elusive. This study aimed to reveal the relationship between RP11­400N13.3 and colorectal cancer. Our results demonstrated that the expression of RP11­400N13.3 was significantly upregulated in both colorectal cancer tissues and cell lines as compared to normal adjacent tissues and normal colonic epithelial cells by RT­qPCR, respectively. Upregulation of RP11­400N13.3 was found to be correlated with a poor overall survival rate. Functional studies revealed that RP11­400N13.3 facilitated the proliferation, migration, invasion and tumor growth of colorectal cancer cells while inhibiting the apoptosis of cancer cells in vitro and in vivo. We also observed that RP11­400N13.3 serves as a sponge for miR­4722­3p, and that P2Y receptor family member 8 (P2RY8) was predicted to be a target of miR­4722­3p by bioinformatics analysis. Western blot assay indicated that the expression of P2RY8 was negatively or positively regulated by miR­4722­3p or RP11­400N13.3. In addition, rescue experiments revealed that RP11­400N13.3 promoted proliferation, migration and invasion by directly regulating the expression of miR­4722­3p and P2RY8. In conclusion, our results revealed that RP11­400N13.3 promoted colorectal cancer progression via modulating the miR­4722­3p/P2RY8 axis, thus suggesting RP11­400N13.3 as a potential therapeutic target for the treatment of colorectal cancer.

Accurate stacked-sheet counting method based on deep learning.

The accurate counting of laminated sheets, such as packing or printing sheets in industry, is extremely important because it greatly affects the economic cost. However, the different thicknesses, adhesion properties, and breakage points and the low contrast of sheets remain challenges to traditional counting methods based on image processing. This paper proposes a new stacked-sheet counting method with a deep learning approach using the U-Net architecture. A specific dataset according to the characteristics of stack side images is collected. The stripe of the center line of each sheet is used for semantic segmentation, and the complete side images of the slices are segmented via training with small image patches and testing with original large images. With this model, each pixel is classified by multi-layer convolution and deconvolution to determine whether it is the target object to be detected. After the model is trained, the test set is used to test the model, and a center region segmentation map based on the pixel points is obtained. By calculating the statistical median value of centerline points across different sections in these segmented images, the number of sheets can be obtained. Compared with traditional image algorithms in real product counting experiments, the proposed method can achieve better performance with higher accuracy and a lower error rate.

LncPRYP4-3 serves as a novel diagnostic biomarker for dissecting subtypes of metabolic associated fatty liver disease by targeting RPS4Y2.

Longitudinal studies have improved current diagnostics and management of metabolic associated fatty liver disease (MAFLD) patients by liver biopsy and therapeutic intervention, yet the deficiency of biomarker spectrum for dissecting subtypes largely hinders the symptomatic treatment. We originally enriched serum from peripheral blood of 618 healthy donors (HD) and 580 MAFLD (400 NAFL, 180 NASH) patients according to multiple clinicopathological indicators. Microarray profiling and qRT-PCR were conducted to identify lncRNAs as candidate biomarkers of MAFLD. Then, we analyzed the matching score of the indicated lncRNA with CAP or MAFLD-associated pathological parameters as well. Additionally, we took advantage of interaction network together with gene expression profiling analysis to further explore the underlying target genes of the identified lncRNA. Herein, we found CAP in nearly all of the NAFL (399/400) and NASH (179/180) patients was higher than that in the HDs (611/618). The differentially expressed lncRNAs were involved in multiple metabolic or immunologic processes by regulating MAFLD-associated pathways. Of them, serum lncPRYP4-3 was identified as a novel candidate biomarker of MAFLD, which was further confirmed by correlation analysis with clinical indicators. Thereafter, we deduced PRS4Y2 was a candidate target of lncPRYP4-3 and mediated the dysfunction in NAFL and NASH patients. Serum lncPRYP4-3 served as a novel biomarker of MAFLD and helped distinguish the subtypes and benefit precise intervention therapy. Our findings also provided overwhelming new evidence for the alteration in biological processes and gene ontology in MAFLD patients.

Atractylenolide II prevents radiation damage via MAPKp38/Nrf2 signaling pathway.

Ionizing radiation (IR) can act as a negative factor for human homeostasis, by causing and even aggravating a series of pathological conditions. To protect the intactness of normal tissues, effective anti-radiation drugs are urgently needed for alleviating the outcomes of radioactive damage. In this study, we demonstrate that atractylenolide II (ATR II), a sesquiterpenoid monomer extracted from traditional Chinese medicine atractylodes macrocephala, can markedly suppress IR damage by promoting the expression of antioxidant factors heme oxygenase-1 (HO-1) and NAD(P)H dehydrogenase quinone oxido-reductase 1 (NQO-1), which are mediated by nuclear factor-erythroid 2-like 2 (Nrf2) signaling pathway. Furthermore, here we reveal that ATR II effectively upregulates the expression of mitogen-activated protein kinase p38 (MAPKp38), which also acts as a regulator of Nrf2 signaling cascade. Indeed, treatment with a MAPKp38 inhibitor can significantly downregulate the expression of Nrf2 and its downstream target genes HO-1 and NQO-1 and, consequently, abolish the protective effect of ATR II against IR. Consistently, ATR II also has a protective function against IR-induced damage in animal models. In conclusion, our study provides an unexpected function of ATR II in preventing IR-induced damage by modulating MAPKp38/Nrf2 signaling pathway.

Complete grid pattern decoding method for a one-shot structured light system.

Structured light 3D reconstruction methods using a De Bruijn sequence-based color grid pattern have an impressive advantage of fast and accurate decoding, which leads to fast 3D reconstruction. They are especially suitable for capturing moving objects. However, the drawback of these methods is their high false decoding rate while dealing with feature points at the object's boundaries, and objects can be prone to becoming deformed by the uneven structure of the dynamic scene. To solve this problem, we present an efficient opened-grid-point detector and a complete grid pattern decoding method. Specifically, a new, to the best of our knowledge, color grid pattern is designed to reduce the influence of color noise and increase the density of 3D cloud points. In addition, a LCD screen projected with the proposed pattern is utilized to calibrate the camera-projector system. The experiments, conducted in a laboratory without a light curtain, demonstrate that the proposed method can fully satisfy the requirements of real applications.

Nrf2 played an important role in radiation protection effect of low-level laser exposed on umbilical cord mesenchymal stem cell.

To investigate the protective function of low-level laser irradiation (LLLI) against ionizing irradiation and explore the molecular mechanism of photomodulation of Nrf2 protein, the impact of LLLI (635 nm, 5.7 J/cm2) before 2 Gy gamma ray radiation of radio-sensitive tissue hematopoietic stem cells was evaluated. As a result, reduced levels of reactive oxygen species and increased expression of antioxidant enzymes were detected. Moreover, increased expression of Nrf2 was observed after LLLI, whereas brusatol pretreatment before LLLI abolished this effect. In vivo, transplantation of human umbilical cord mesenchymal stem cells (hUC-MSCs) was employed for therapy of hematopoietic function in an acute radiation sickness (H-ARS) mouse model, which was induced by 6-Gy ionizing irradiation; different hUC-MSC pretreatments including LLLI and Nrf2 RNAi were accounted for during experimental grouping. LLLI treatment of cells significantly increased the erythrocyte count and number of myelopoiesis clones (P < 0.05), but such improvements were reduced by Nrf2 RNAi pretreatment compared with cells transplanted without intervention. Therefore, LLLI may improve the radiation protection effect through molecular mechanisms related to the Nrf2 antioxidant pathway.

Radiation Responses of Human Mesenchymal Stem Cells Derived From Different Sources.

Mesenchymal stem cells (MSCs) derived from different tissues may aid in the regeneration of radiation-induced organ lesions; however, the radiation responses of human MSCs from different sources are unknown. In our study, a comparison of the results from cell proliferation, apoptosis, cell cycle, DNA damage, and DNA repair assays consistently showed that MSCs derived from adipose tissue possess a significantly stronger radiation resistance capacity than MSCs derived from umbilical cord and gingival, which is accompanied by a higher level of phosphorylated signal transducer and activator of transcription 3 (Stat3) expression. This reminds us Stat3 could be a potential biomarker of radiation resistance. These findings provide a better understanding of radiation-induced biologic responses in MSCs and may lead to the development of better strategies for stem cell treatment and cancer therapy.

Integrated Analysis of the Altered lncRNAs and mRNAs Expression in 293T Cells after Ionizing Radiation Exposure.

Tissue and cell damage caused by ionizing radiation is often highly genotoxic. The swift repair of DNA damage is crucial for the maintenance of genomic stability and normal cell fitness. Long noncoding RNAs (lncRNAs) have been reported to play an important role in many physiological and pathological processes in cells. However, the exact function of lncRNAs in radiation-induced DNA damage has yet to be elucidated. Therefore, this study aimed to analyze the potential role of lncRNAs in radiation-induced DNA damage. We examined the expression profiles of lncRNAs and mRNAs in 293T cells with or without 8 Gy irradiation using high-throughput RNA sequencing. We then performed comprehensive transcriptomic and bioinformatic analyses of these sequencing results. A total of 18,990 lncRNAs and 16,080 mRNAs were detected in all samples. At 24 h post irradiation, 49 lncRNAs and 323 mRNAs were differentially expressed between the irradiation group and the control group. qRT-PCR was used to verify the altered expression of six lncRNAs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated that the predicted genes were mainly involved in the histone mRNA metabolic process and Wnt signaling pathways. This study may provide novel insights for the study of lncRNAs in radiation-induced DNA damage.

Analysis of Circular RNA Expression Profile in HEK 293T Cells Exposed to Ionizing Radiation.

Radiation therapy is one of the most common cancer treatments. It is important to understand how cells respond to ionizing radiation (IR) to improve therapeutic efficacy. Circular RNAs (circRNAs) recently have been found to regulate a variety of cellular processes. However, it is poorly defined that their expression pattern and their identity in cells following IR exposure. Here, we performed high-throughput sequencing and comprehensive analysis of circRNA expression in human embryonic kidney (HEK) 293T cells before and after irradiation. We identified totally 5592 circRNAs and discovered 1038 new circRNAs. We found 158 circRNAs with significantly differential expression after IR exposure. Among them, there were 61 upregulated and 97 downregulated circRNAs. Using Gene Ontology, Kyoto Encyclopedia of Genes and Genomes pathway, and circRNA-microRNA-messenger RNA network analyses, we found the differentially expressed circRNAs might be involved in the signal pathways of oxidative phosphorylation, epithelial growth factor receptor (EGFR) tyrosine kinase inhibitor resistance, and mammalian target of rapamycin (mTOR) signaling.

Expression of microRNAs-106b in nonsmall cell lung cancer.

AIM: To explore the expression of microRNA-106b (miRNA-106b) in nonsmall cell lung cancer (NSCLC). SETTINGS AND DESIGN: miRNAs are short regulatory RNAs that negatively modulate gene expression at the posttranscriptional level, and are deeply involved in the pathogenesis of several types of cancer. miRNA-106b has been shown to play an oncogenic role in tumor progression. The expression of miRNA-106b is detected in this study. SUBJECTS AND METHODS: Quantitative reverse transcription polymerase chain reaction and Northern blotting were used to detect the expression level of miRNA-106b in 200 NSCLC samples. STATISTICAL ANALYSIS USED: All statistical analyses were performed using SPSS 16.0 software. Results were statistically evaluated using the Kruskal-Wallis test and Mann-Whitney U-test. Survival curves were estimated by the Kaplan-Meier method and P < 0.05 was considered to be statistically significant. RESULTS: miRNA-106b expression is increased in NSCLC tissues. Statistical analysis showed that overexpression of miRNA-106b was strongly associated with lymph node metastasis, stage of tumor node metastasis classification, and poor prognosis. Moreover, there was a significant difference in the miRNA-106b expression levels between smoking and nonsmoking patients. Multivariate Cox regression analysis showed that miRNA-106b was an independent prognostic factor for NSCLC patients. CONCLUSIONS: These data suggest that aberrantly expressed miRNA-106b may contribute to the development of NSCLC.

Simultaneous Segmentation of Leukocyte and Erythrocyte in Microscopic Images Using a Marker-Controlled Watershed Algorithm.

The density or quantity of leukocytes and erythrocytes in a unit volume of blood, which can be automatically measured through a computer-based microscopic image analysis system, is frequently considered an indicator of diseases. The segmentation of blood cells, as a basis of quantitative statistics, plays an important role in the system. However, many conventional methods must firstly distinguish blood cells into two types (i.e., leukocyte and erythrocyte) and segment them in independent procedures. In this paper, we present a marker-controlled watershed algorithm for simultaneously extracting the two types of blood cells to simplify operations and reduce computing time. The method consists of two steps, that is, cell nucleus segmentation and blood cell segmentation. An image enhancement technique is used to obtain the leukocyte marker. Two marker-controlled watershed algorithms are based on distance transformation and edge gradient information to acquire blood cell contour. The segmented leukocytes and erythrocytes are obtained simultaneously by classification. Experimental results demonstrate that the proposed method is fast, robust, and efficient.

Knockdown of RMI1 impairs DNA repair under DNA replication stress.

RMI1 (RecQ-mediated genome instability protein 1) forms a conserved BTR complex with BLM, Topo IIIα, and RMI2, and its absence causes genome instability. It has been revealed that RMI1 localizes to nuclear foci with BLM and Topo IIIα in response to replication stress, and that RMI1 functions downstream of BLM in promoting replication elongation. However, the precise functions of RMI1 during replication stress are not completely understood. Here we report that RMI1 knockdown cells are hypersensitive to hydroxyurea (HU). Using comet assay, we show that RMI1 knockdown cells exhibit accumulation of broken DNAs after being released from HU treatment. Moreover, we demonstrate that RMI1 facilitates the recovery from activated checkpoint and resuming the cell cycle after replicative stress. Surprisingly, loss of RMI1 results in a failure of RAD51 loading onto DNA damage sites. These findings reveal the importance of RMI1 in response to replication stress, which could explain the molecular basis for its function in maintaining genome integrity.