Machine learning recognition of protein secondary structures based on two-dimensional spectroscopic descriptors.

Protein secondary structure discrimination is crucial for understanding their biological function. It is not generally possible to invert spectroscopic data to yield the structure. We present a machine learning protocol which uses two-dimensional UV (2DUV) spectra as pattern recognition descriptors, aiming at automated protein secondary structure determination from spectroscopic features. Accurate secondary structure recognition is obtained for homologous (97%) and nonhomologous (91%) protein segments, randomly selected from simulated model datasets. The advantage of 2DUV descriptors over one-dimensional linear absorption and circular dichroism spectra lies in the cross-peak information that reflects interactions between local regions of the protein. Thanks to their ultrafast (∼200 fs) nature, 2DUV measurements can be used in the future to probe conformational variations in the course of protein dynamics.

Recent Advances in the Modification and Improvement of Bioprosthetic Heart Valves.

Valvular heart disease (VHD) has become a burden and a growing public health problem in humans, causing significant morbidity and mortality worldwide. An increasing number of patients with severe VHD need to undergo heart valve replacement surgery, and artificial heart valves are in high demand. However, allogeneic valves from donors are lacking and cannot meet clinical practice needs. A mechanical heart valve can activate the coagulation pathway after contact with blood after implantation in the cardiovascular system, leading to thrombosis. Therefore, bioprosthetic heart valves (BHVs) are still a promising way to solve this problem. However, there are still challenges in the use of BHVs. For example, their longevity is still unsatisfactory due to the defects, such as thrombosis, structural valve degeneration, calcification, insufficient re-endothelialization, and the inflammatory response. Therefore, strategies and methods are needed to effectively improve the biocompatibility and longevity of BHVs. This review describes the recent research advances in BHVs and strategies to improve their biocompatibility and longevity.

Quality of life and decision regret in patients with late-hypothyroidism after radioiodine treatment for Graves' disease.

OBJECTIVE: Patients with Graves' disease often engage in shared decision-making to select an individualised treatment regimen from multiple options. Radioactive iodine (RAI) is one of the treatment choices for their condition, aims to improve quality of life and well-being. Likewise, dissatisfaction with treatment outcomes can result in decision regret. We employed validated questionnaires to assess the prospective quality of life, decision regret and relative factors involved in decision-making of patients with late hypothyroidism after RAI therapy. METHODS: A questionnaire survey was conducted among patients in hypothyroidism status for more than 1 year after RAI therapy. Disease-specific and generic QoL were assessed using the short form of thyroid-related patient-reported outcome (ThyPRO-39) questionnaire. Patient satisfaction regarding their decision to undergo RAI was assessed using the Decision Regret Scale (DRS) and patients were asked about the importance of relative factors in decision-making. RESULTS: Of 254 patients who responded to the survey, the mean age of patients was 45.3 years (range: 18-78 years) and the median time from RAI therapy to survey was 4 years (range: 1-30 years). Patients' median and mean DRS score were 34.4 and 38.8 (range: 0-100), respectively. A total of 100 (39.4%) patients express absent-to-mild regret (score: 0-25), 154 (60.6%) patients express moderate-to-severe regret (score: >25). The mean score of the absent-to-mild regret group were significantly higher than those of the moderate-to-severe regret group on most ThyPRO-39 scales. A statistically significant positive correlation was observed between DRS score and most ThyPRO-39 scale score. There was a significant positive association between higher DRS score and longer time intervals after RAI treatment, a brief duration of hyperthyroidism, and the significance of long-time outpatient follow-up. More decision regret was negatively associated Iodine-free diet, ineffectiveness of ATD, fear of surgery. CONCLUSION: Impairment of quality of life was positively correlated with decision regret in patients with late-hypothyroidism after radioiodine therapy. Patients with insufficient information support before decision-making are more likely to have higher decision regret after treatment. Our findings suggest that health providers should fully communicate with patients and provide information support in multiple dimensions during the shared-decision-making process.

Synthesis and biological evaluation of novel penindolone derivatives as potential antiproliferative agents against SCLC in vitro.

Small cell lung cancer (SCLC) keeps on the leading cause of cancer mortality world widely, while there is lack of efficient therapeutic drugs especially for the resistant ones. In this work, a compound named penindolone (PND) with new skeleton was found to show weak inhibitory effect (IC50 = 42.5 µM) on H69AR cells (SCLC, adriamycin-resistant) proliferation by screening our in-house compound library. With the aim of improving its low potency, a series of PND derivatives were synthesized and biologically evaluated by the Sulforhodamine B (SRB) assay. Among all tested derivatives, compound 5h possessed higher antiproliferation potency (IC50 = 1.6 µM). Furthermore, preliminary mechanism investigation revealed that 5h was able to induce apoptosis and arrest the cell cycle at G0/G1 phase. These findings suggest that this novel skeleton has expanded the anti-SCLC compound reservoir and provided a new drug lead.

DSOMF: A Dynamic Environment Simultaneous Localization and Mapping Technique Based on Machine Learning.

To address the challenges of reduced localization accuracy and incomplete map construction demonstrated using classical semantic simultaneous localization and mapping (SLAM) algorithms in dynamic environments, this study introduces a dynamic scene SLAM technique that builds upon direct sparse odometry (DSO) and incorporates instance segmentation and video completion algorithms. While prioritizing the algorithm's real-time performance, we leverage the rapid matching capabilities of Direct Sparse Odometry (DSO) to link identical dynamic objects in consecutive frames. This association is achieved through merging semantic and geometric data, thereby enhancing the matching accuracy during image tracking through the inclusion of semantic probability. Furthermore, we incorporate a loop closure module based on video inpainting algorithms into our mapping thread. This allows our algorithm to rely on the completed static background for loop closure detection, further enhancing the localization accuracy of our algorithm. The efficacy of this approach is validated using the TUM and KITTI public datasets and the unmanned platform experiment. Experimental results show that, in various dynamic scenes, our method achieves an improvement exceeding 85% in terms of localization accuracy compared with the DSO system.

miR-138-5p targets MCU to inhibit mitochondrial biogenesis and colorectal cancer growth.

miR-138-5p has been identified as a novel cancer-related miRNA molecule in a variety of malignancies. However, the functions and mechanisms underlying miR-138-5p in colorectal carcinoma (CRC) remains largely unknown. In the present study, we analysed the biological effects and clinical significance of miR-138-5p in CRC. miR-138-5p expression was analysed by quantitative real-time PCR in CRC tissues and cell lines. The effects of miR-138-5p on CRC cell growth was detected by cell proliferation, colony formation, cell cycle and cell apoptosis assays in vitro and in vivo. Our data showed that miR-138-5p was significantly downregulated in CRC. Downregulated miR-138-5p was related with poor prognosis in patients with CRC. miR-138-5p suppressed CRC growth but promoted cell death both in vitro and in vivo. Online predictions and integrated experiments identified that miR-138-5p targeted MCU, and downregulated miR-138-5p promoted mitochondrial biogenesis in CRC. In the light of the underlying mechanisms, our results indicated that downregulated miR-138-5p led to increased expression of MCU, which subsequently increased the production of ROS to promote CRC growth. Our results indicated that downregulated miR-138-5p strengthened mitochondrial biogenesis through targeting MCU, thus contributing to CRC cell growth, which may provide a potential therapeutic target for CRC.

Role of metformin in inflammation.

BACKGROUND: Metformin has good anti-hyperglycemic effectiveness, but does not induce hypoglycemia，is very safe, and has become the preferred drug for the treatment of type 2 diabetes. Recently, the other effects of metformin, such as being anti-inflammatory and delaying aging, have also attracted increased attention. METHODS AND RESULTS: The relevant literatures on pubmed and other websites for reading, classification and sorting, and did not involve any animal experiments. CONCLUSION: Metformin has anti-inflammatory effects through multiple routes, which provides potential therapeutic targets for certain inflammatory diseases, such as neuroinflammation and rheumatoid arthritis. In addition, inflammation is a key component of tumor occurrence and development ; thus, targeted inflammatory intervention is a significant benefit for both cancer prevention and treatment. Therefore, metformin may have further potential for inflammation-related disease prevention and treatmen. However, the inflammatory mechanism is complex; various molecules are connected and influence each other. For example, metformin significantly inhibits p65 nuclear translocation, but pretreatment with compound C, an AMPK inhibitor, abolishes this effect, and silencing of HMGB1 inhibits NF-κB activation . SIRT1 deacetylates FoxO, increasing its transcriptional activity . mTOR in dendritic cells regulates FoxO1 via AKT. The interactions among various molecules should be further explored to clarify their specific mechanisms and provide more direction for the treatment of inflammatory diseases, as well as cancer.

Epigallocatechin-3-Gallate Inhibits Atrial Fibrosis and Reduces the Occurrence and Maintenance of Atrial Fibrillation and its Possible Mechanisms.

BACKGROUND: Atrial fibrosis is one of the main causes of the onset and recurrence of atrial fibrillation (AF), for which there is no effective treatment. The aim of this study was to investigate the effect and mechanism of epigallocatechin-3-gallate (EGCG) on AF in rats. METHODS: The rat model of AF was established by rapid pacing induction after angiotensin-II (Ang-II) induced atrial fibrosis to verify the relationship between atrial fibrosis and the AF. The expression levels of TGF-ß/Smad3 pathway molecules and lysyl oxidase (LOX) in AF were detected. Subsequently, EGCG was used to intervene Ang-II-induced atrial fibrosis to explore the role of EGCG in the treatment of AF and its inhibitory mechanism on fibrosis. It was further verified that EGCG inhibited the production of collagen and the expression of LOX through the TGF-ß/Smad3 pathway at the cellular level. RESULTS: The results showed that the induction rate and maintenance time of AF in rats increased with the increase of the degree of atrial fibrosis. Meanwhile, the expressions of Col I, Col III, molecules related to TGF-ß/Smad3 pathway, and LOX increased significantly in the atrial tissues of rats in the Ang-II induced group. EGCG could reduce the occurrence and maintenance time of AF by inhibiting the degree of Ang-induced rat atrial fibrosis. Cell experiments confirmed that EGCG could reduce the synthesis of collagen and the expression of LOX in cardiac fibroblast induced by Ang-II. The possible mechanism is to down-regulate the expression of genes and proteins related to the TGF-ß/Smad3 pathway. CONCLUSION: EGCG could downregulate the expression levels of collagen and LOX by inhibiting the TGF-ß/Smad3 signaling pathway, alleviating Ang-II-induced atrial fibrosis, which in turn inhibited the occurrence and curtailed the duration of AF.

Prognostic role of pretreatment 18F-FDG PET/CT and hematological parameters in relapsed/refractory Hodgkin lymphoma patients treated with immune checkpoint inhibitors and chemotherapy: a dual-center cohort study.

BACKGROUND: The combination of anti-programmed death-1 antibodies and chemotherapy is effective; however, there are no reliable outcome prediction factors. We investigated the prognostic factors based on 18Fluorine-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) quantitative and hematological parameters to predict progression-free survival (PFS) in relapsed/refractory classical Hodgkin lymphoma (R/R cHL) patients treated with immune checkpoint inhibitors (ICIs) and chemotherapy. METHODS: This retrospective study included 31 patients who underwent 18F-FDG PET/CT before and during treatment. Pretreatment metabolic and hematological parameters were evaluated using Cox regression analysis to identify predictors of PFS. Based on the cut-off values calculated using the receiver operating characteristic (ROC) curve, patients were classified into low-, intermediate-, and high-risk groups. Kaplan-Meier curves and the log-rank test were used to compare survival differences between the groups. RESULTS: Cox multivariable analysis indicted that the treatment response based on Lactate dehydrogenase (LDH), Lugano classification and SUVmax were independent predictors of PFS (P = 0.004, 0.007 and 0.039, respectively). The optimal cut-off values for SUVmax and LDH were 11.62 and 258.5 U/L, respectively (P < 0.01). Survival curves showed that LDH ≥ 258.5U/L and SUVmax ≥ 11.62 were correlated to shorter PFS (P < 0.001, P = 0.003, respectively). The differences in PFS between the low-, intermediate-, and high-risk groups were statistically significant (P = 0.0043). CONCLUSION: In R/R cHL patients treated with ICIs and chemotherapy, Lugano classification, SUVmax, and LDH were significantly correlated with PFS. The combination of metabolic and hematological parameters predicts PFS and may help to improve patient selection.

Isolation and functional analysis of OsAOS1 promoter for resistance to Nilaparvata lugens Stål infestation in rice.

Insect pests have a great impact on the yield and quality of crops. Insecticide applications are an effective method of pest control, however, they also have adverse effects on the environment. Using insect-inducible promoters to drive insect-resistant genes in transgenic crops is a potential sustainable pest management strategy, but insect-inducible promoters have been rarely reported. In this study, we found rice allene oxide synthase gene (AOS, LOC_Os03g12500) can be highly upregulated following brown planthopper (Nilaparvata lugens Stål, BPH) infestation. Then, we amplified the promoter of OsAOS1 and the ß- glucuronidase reporter gene was used to analyze the expression pattern of the promoter. Through a series of 5' truncated assays, three positive regulatory regions in response to BPH infestation in the promoter were identified. The transgenic plants, P1R123-min 35S and P1TR1-min 35S promoter-driven snowdrop lectin (Galanthus nivalis agglutinin, GNA) gene, demonstrated the highest expression levels of GNA and lowest BPH survival. Our work identified a BPH-inducible promoter and three positive regions within it. Transgenic rice with GNA driven by OsAOS1 promoter and positive regions exhibited an expected lethal effect on BPH. This study proved the application potential of BPH-inducible promoter and provided a novel path for the selection of insect-resistant tools in the future.

The overview of Mitogen-activated extracellular signal-regulated kinase (MEK)-based dual inhibitor in the treatment of cancers.

Mitogen-activated extracellular signal-regulated kinase 1 and 2 (MEK1/2) are the critical components of the mitogen-activated protein kinase/extracellular signal-regulated kinase 1 and 2 (MAPK/ERK1/2) signaling pathway which is one of the well-characterized kinase cascades regulating cell proliferation, differentiation, growth, metabolism, survival and mobility both in normal and cancer cells. The aberrant activation of MAPK/ERK1/2 pathway is a hallmark of numerous human cancers, therefore targeting the components of this pathway to inhibit its dysregulation is a promising strategy for cancer treatment. Enormous efforts have been done in the development of MEK1/2 inhibitors and encouraging advancements have been made, including four inhibitors approved for clinical use. However, due to the multifactorial property of cancer and rapidly arising drug resistance, the clinical efficacy of these MEK1/2 inhibitors as monotherapy are far from ideal. Several alternative strategies have been developed to improve the limited clinical efficacy, including the dual inhibitor which is a single drug molecule able to simultaneously inhibit two targets. In this review, we first introduced the activation and function of the MAPK/ERK1/2 components and discussed the advantages of MEK1/2-based dual inhibitors compared with the single inhibitors and combination therapy in the treatment of cancers. Then, we overviewed the MEK1/2-based dual inhibitors for the treatment of cancers and highlighted the theoretical basis of concurrent inhibition of MEK1/2 and other targets for development of these dual inhibitors. Besides, the status and results of these dual inhibitors in both preclinical and clinical studies were also the focus of this review.

Skeleton-Based Human Pose Recognition Using Channel State Information: A Survey.

With the increasing demand for human-computer interaction and health monitoring, human behavior recognition with device-free patterns has attracted extensive attention. The fluctuations of the Wi-Fi signal caused by human actions in a Wi-Fi coverage area can be used to precisely identify the human skeleton and pose, which effectively overcomes the problems of the traditional solution. Although many promising results have been achieved, no survey summarizes the research progress. This paper aims to comprehensively investigate and analyze the latest applications of human behavior recognition based on channel state information (CSI) and the human skeleton. First, we review the human profile perception and skeleton recognition progress based on wireless perception technologies. Second, we summarize the general framework of precise pose recognition, including signal preprocessing methods, neural network models, and performance results. Then, we classify skeleton model generation methods into three categories and emphasize the crucial difference among these typical applications. Furthermore, we discuss two aspects, such as experimental scenarios and recognition targets. Finally, we conclude the paper by summarizing the issues in typical systems and the main research directions for the future.

Design, synthesis and antitumor activity evaluation of trifluoromethyl-substituted pyrimidine derivatives.

In order to find efficient new antitumor drugs, a series of novel trifluoromethyl-substituted pyrimidine derivatives were designed and synthesized, and the bioactivity against four human tumor cells (PC-3, MGC-803, MCF-7 and H1975) was evaluated by MTT assay. Compound 17v displayed potent anti-proliferative activity on H1975 (IC50 = 2.27 µΜ), which was better than the positive control 5-FU (IC50 = 9.37 µΜ). Further biological evaluation studies showed that compound 17v induced apoptosis of H1975 cells and arrested the cell cycle at G2/M phase. Furthermore, compound 17v induced H1975 cells apoptosis through increasing the expression of pro-apoptotic proteins Bax and p53 and down-regulating the anti-apoptotic protein Bcl-2. In addition, compound 17v was able to be tightly embedded in the active pocket of EGFR. In summary, these results demonstrated that compound 17v has a potential as a lead compound for further investigation.

Design, synthesis and biological evaluation of novel 2,4-disubstituted quinazoline derivatives targeting H1975 cells via EGFR-PI3K signaling pathway.

In order to find new and highly effective anti-tumor drugs with targeted therapeutic effects, a series of novel 4-aminoquinazoline derivatives containing N-phenylacetamide structure were designed, synthesized and evaluated for antitumor activity against four human cancer cell lines (H1975, PC-3, MDA-MB-231 and MGC-803) using MTT assay. The results showed that the compound 19e had the most potent antiproliferative activity against H1975, PC-3, MDA-MB-231 and MGC-803 cell lines. At the same time, compound 19e could significantly inhibit the colony formation and migration of H1975 cells. Compound 19e also arrested the H1975 cell cycle in the G1 phase and mediated cell apoptosis, promoted the accumulation of ROS in H1975 cells. Furthermore, compound 19e exerted antitumor effect in vitro by reducing the expression of anti-apoptotic protein Bcl-2 and increasing the pro-apoptotic protein Bax and p53. Mechanistically, compound 19e could significantly decreased the phosphorylation of EGFR and its downstream protein PI3K in H1975 cells. Which indicated that compound 19e targeted H1975 cell via interfering with EGFR-PI3K signaling pathway. Molecular docking showed that compound 19e could bind into the active pocket of EGFR. Those work suggested that compound 19e would have remarkable implications for further design of anti-tumor agents.

Ultrafast stimulated resonance Raman signatures of lithium polysulfides for shuttling effect characterization: An ab initio study.

The shuttling effect is a crucial obstacle to the practical deployment of lithium sulfur batteries (LSBs). This can be ascribed to the generation of lithium polysulfide (LiPS) redox intermediates that are soluble in the electrolyte. The detailed mechanism of the shuttling, including the chemical structures responsible for the loss of effective mass and the dynamics/kinetics of the redox reactions, are not clear so far. To obtain this microscopic information, characterization techniques with high spatial and temporal resolutions are required. Here, we propose that resonance Raman spectroscopy combined with ultrafast broadband pulses is a powerful tool to reveal the mechanism of the shuttling effect. By combining the chemical bond level spatial resolution of resonance Raman and the femtosecond scale temporal resolution of the ultrafast pulses, this novel technique holds the potential of capturing the spectroscopic fingerprints of the LiPS intermediates during the working stages of LSBs. Using ab initio simulations, we show that, in addition to the excitation energy selective enhancement, resonance Raman signals of different LiPS intermediates are also characteristic and distinguishable. These results will facilitate the real-time in situ monitoring of LiPS species and reveal the underlying mechanism of the shuttling effect.

Safety assessment of transgenic Cry2Aa rice to a generalist predator, Paederus fuscipes Curtis (Coleoptera: Staphylinidae).

The insecticidal crystal proteins of Cry2A family from Bacillus thuringiensis (Bt) are important candidate proteins expressed in gene pyramiding Bt crops. A transgenic rice line (T2A-1) harboring a synthetic Cry2A* (Cry2Aa) gene showed effective resistance to some lepidopteran rice pests. As a generalist predator in rice ecosystems, the rove beetle (Paederus fuscipes) can prey on many rice insect pests such as planthoppers. Considering the possible exposure of Cry2Aa to P. fuscipes through tritrophic food chain, it is necessary to assess the potential risks of T2A-1 rice to this predator. In this study, a tritrophic experiment was conducted to assess the prey-mediated effects of Cry2Aa on P. fuscipes through the T2A-1 rice-Nilaparvata lugens-P. fuscipes food chain. After preying on N. lugens nymphs reared on T2A-1, no accumulated Cry2Aa could be detected in P. fuscipes adults, despite Cry2Aa being detected in N. lugens. In addition, no harmful effects were detected on the life table parameters of P. fuscipes in this tritrophic chain. Additionally, direct exposure to a high dose of purified Cry2Aa protein, representing the worst case scenario, showed no significant adverse effects on the development of P. fuscipes. These results showed that transgenic Cry2Aa rice had no harmful effects on P. fuscipes.

Assessing the effects of Cry2Aa protein on Habrobracon hebetor (Hymenoptera: Braconidae), a parasitoid of Indian meal moth, Plodia interpunctella (lepidoptera: Pyralidae).

Transgenic crops express Cry proteins exhibit high resistant to target insect pests. When we evaluate the effects of Cry proteins on the parasitoid of target insect pest via tritrophic experiments (transgenic plant-target insect pest-parasitoid) host quality of parasitoids might decrease because of insecticidal protein ingestion, this would cause host-quality mediated effects and influence the accuracy of biosafety assessment. In the current study, high dose of Cry2Aa protein was injected into the hemolymph of Plodia interpunctella by microinjection, and the hemolymph was used as the carrier to deliver Cry protein to Habrobracon hebetor, which has been previously reported as an ectoparasitoid of P. interpunctella larval, in order to avoid the "host-quality mediated effects". Results showed that injected Cry2Aa remained at high concentration and bioactive in the hemolymph of P. interpunctella parasitized by H. hebetor, the hemolymph of P. interpunctella could be used as carriers of Cry protein to H. hebetor, and high dose of Cry2Aa have no negative impacts on the development time, weight of pupa, sex ratio, adults weight (male and female), adult longevity and fecundity, and the activity of stress-related enzymes of H. hebetor. However, the hemolymph of P. interpunctella injected into Galanthus nivalis agglutinin (the positive control) showed significant negative impact on these parameters measured in the present study of H. hebetor. This indicated that Cry2Aa protein had no detrimental effects on the biological parameters of H. hebetor measured in the current study. Meanwhile, this study provides a new method for the safety evaluation of the ectoparasitoids of target pest and might be expanded to the other species of ectoparasitoids of target insects of Cry proteins in biosafety risk assessment.

SD-VIS: A Fast and Accurate Semi-Direct Monocular Visual-Inertial Simultaneous Localization and Mapping (SLAM).

In practical applications, how to achieve a perfect balance between high accuracy and computational efficiency can be the main challenge for simultaneous localization and mapping (SLAM). To solve this challenge, we propose SD-VIS, a novel fast and accurate semi-direct visual-inertial SLAM framework, which can estimate camera motion and structure of surrounding sparse scenes. In the initialization procedure, we align the pre-integrated IMU measurements and visual images and calibrate out the metric scale, initial velocity, gravity vector, and gyroscope bias by using multiple view geometry (MVG) theory based on the feature-based method. At the front-end, keyframes are tracked by feature-based method and used for back-end optimization and loop closure detection, while non-keyframes are utilized for fast-tracking by direct method. This strategy makes the system not only have the better real-time performance of direct method, but also have high accuracy and loop closing detection ability based on feature-based method. At the back-end, we propose a sliding window-based tightly-coupled optimization framework, which can get more accurate state estimation by minimizing the visual and IMU measurement errors. In order to limit the computational complexity, we adopt the marginalization strategy to fix the number of keyframes in the sliding window. Experimental evaluation on EuRoC dataset demonstrates the feasibility and superior real-time performance of SD-VIS. Compared with state-of-the-art SLAM systems, we can achieve a better balance between accuracy and speed.

Near-Infrared Fluorescent Peptides with High Tumor Selectivity: Novel Probes for Image-Guided Surgical Resection of Orthotopic Glioma.

The complete excision of glioblastomas with maximal retention of surrounding normal tissues can have a positive effect on the survival status and quality of life of patients. Near-infrared fluorescence (NIRF) optical imaging of the tumor vasculature offers a noninvasive method for detection of early stage glioblastoma and efficient monitoring of therapeutic responses. The aim of this study was to develop a novel NIRF imaging probe as a visualization tool for image-guided surgical resection of orthotopic glioblastoma. In this study, Cy5.5-RKL, Cy5.5-NKL, and Cy5.5-DKL probes were successfully synthesized, and their properties were investigated in vitro and in vivo. In vivo, Cy5.5-RKL and Cy5.5-NKL were able to detect U87MG xenografts for at least 8 h post injection. The maximum tumor-to-muscle ratios of Cy5.5-RKL and Cy5.5-NKL were 7.65 ± 0.72 and 5.43 ± 0.72, respectively. Of the probes, Cy5.5-RKL displayed the best delineation of the boundaries between orthotopic glioblastomas and normal brain tissue at 8 h p.i. In conclusion, NIRF imaging using Cy5.5-RKL is promising not only for diagnostic purposes but also for use in image-guided surgery for orthotopic glioblastoma or other superficial tumors.

Fine Mapping and Candidate Gene Prediction for White Immature Fruit Skin in Cucumber (Cucumis sativus L.).

In this study, a single recessive gene (designated w0) was identified to control the white immature fruit color. Genetic mapping with simple sequence repeats (SSR) markers located the w0 gene in the distal region of cucumber chromosome 3 (Chr.3). Fine mapping was then conducted using the method of draft genome scaffold-assisted chromosome walking with 7304 F2 individuals, which allowed for the assignment of the gene locus to a 100.3 kb genomic DNA region with two flanking markers, Q138 and Q193. Thirteen candidate genes were predicted in the 100.3 kb region. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis showed that the expression of the Csa3G904140 gene, which encodes a two-component response regulator-like protein, was much higher in the immature fruit skin of the green parental line (Q1) than in the white parental line (H4). A coding sequence analysis suggested that a single-base insertion occurred at the ninth exon, resulting in a frameshift mutation in Csa3G904140 of H4, and the mutation was consistent with the phenotype in 17 green/white germplasms. Therefore, Csa3G904140 was taken as the likely candidate gene controlling the immature fruit color of cultivated cucumber. This study will contribute to the cloning of candidate genes and the development of white cucumber cultivars using marker-assisted breeding.