Comparative Genomics Reveals Evolutionary Drivers of Sessile Life and Left-right Shell Asymmetry in Bivalves.

Bivalves are species-rich mollusks with prominent protective roles in coastal ecosystems. Across these ancient lineages, colony-founding larvae anchor themselves either by byssus production or by cemented attachment. The latter mode of sessile life is strongly molded by left-right shell asymmetry during larval development of Ostreoida oysters such as Crassostrea hongkongensis. Here, we sequenced the genome of C. hongkongensis in high resolution and compared it to reference bivalve genomes to unveil genomic determinants driving cemented attachment and shell asymmetry. Importantly, loss of the homeobox gene Antennapedia (Antp) and broad expansion of lineage-specific extracellular gene families are implicated in a shift from byssal to cemented attachment in bivalves. Comparative transcriptomic analysis shows a conspicuous divergence between left-right asymmetrical C. hongkongensis and symmetrical Pinctada fucata in their expression profiles. Especially, a couple of orthologous transcription factor genes and lineage-specific shell-related gene families including that encoding tyrosinases are elevated, and may cooperatively govern asymmetrical shell formation in Ostreoida oysters.

Construction of a Mex3c Gene-Deficient Mouse Model to Study C-FOS Expression in Hypothalamic Nuclei and Observe Morphological Differences in Embryonic Neural Tube Development.

BACKGROUND This study utilized CRISPR/Cas9 gene editing technology to construct a Mex3c gene-deficient mouse model, and studied C-FOS expression in hypothalamic nuclei. MATERIAL AND METHODS Thirty Mex3c-/+ mice, 30 mice in the normal group, and 30 Mex3c-/+ mice were randomly divided into control, leptin, and ghrelin groups according to different intraperitoneal injections. HE and Nissl staining were performed to observe the morphology of hypothalamic nerve cells. The C-FOS expression in hypothalamic nuclei of each group was analyzed by immunohistochemical techniques. HE staining was used to observe neural tube morphology, and LFB staining was used to observe nerve myelin sheath morphology. TEM was used to observe neuronal ultrastructure and immunohistochemical techniques were utilized to analyze nestin expression. RESULTS C-FOS expression was lower in the normal control group than in the leptin and ghrelin groups. The Mex3c control group and the leptin group had higher C-FOS expression than the ghrelin group. In neural tube studies, no significant differences were found in the neural tube pathological sections of E14.5-day embryos in each group. Nestin results demonstrated lower expression in the normal group and there was little difference between the HD and Mex3c groups. CONCLUSIONS Mex3c appears to participate in the regulation of energy metabolism by inducing C-FOS expression in the hypothalamus. The neural tubes of the offspring of Mex3c-/+ mice had defects during development.

Segmenting Brain Tumor Using Cascaded V-Nets in Multimodal MR Images.

In this work, we propose a novel cascaded V-Nets method to segment brain tumor substructures in multimodal brain magnetic resonance imaging. Although V-Net has been successfully used in many segmentation tasks, we demonstrate that its performance could be further enhanced by using a cascaded structure and ensemble strategy. Briefly, our baseline V-Net consists of four levels with encoding and decoding paths and intra- and inter-path skip connections. Focal loss is chosen to improve performance on hard samples as well as balance the positive and negative samples. We further propose three preprocessing pipelines for multimodal magnetic resonance images to train different models. By ensembling the segmentation probability maps obtained from these models, segmentation result is further improved. In other hand, we propose to segment the whole tumor first, and then divide it into tumor necrosis, edema, and enhancing tumor. Experimental results on BraTS 2018 online validation set achieve average Dice scores of 0.9048, 0.8364, and 0.7748 for whole tumor, tumor core and enhancing tumor, respectively. The corresponding values for BraTS 2018 online testing set are 0.8761, 0.7953, and 0.7364, respectively. We also evaluate the proposed method in two additional data sets from local hospitals comprising of 28 and 28 subjects, and the best results are 0.8635, 0.8036, and 0.7217, respectively. We further make a prediction of patient overall survival by ensembling multiple classifiers for long, mid and short groups, and achieve accuracy of 0.519, mean square error of 367240 and Spearman correlation coefficient of 0.168 for BraTS 2018 online testing set.

Radiofrequency ablation for lung squamous cell carcinoma in a single-lung patient: A case report and literature review.

RATIONALE: High morbidity and high mortality are the main features of non-small cell lung cancer (NSCLC). Radiofrequency ablation, which produces a large amount of heat to kill tumor cells, is one effective way to treat this disease. PATIENT CONCERNS: We report the case of a 74-year-old man who presented with a 1-month history of right chest pain. His left lung was removed 12 years prior. Chest computed tomography (CT) revealed a mass in the right lower lobe. DIAGNOSES: An excision biopsy of the mass showed lung squamous cell carcinoma. INTERVENTIONS: We performed radiofrequency ablation. OUTCOMES: The patient underwent 3.5 and 10 months of follow-up, with a partial response and complete remission, respectively. LESSONS: CT-guided radiofrequency ablation is a safe and an effective minimally invasive treatment option. Radiofrequency appears to be a valuable alternative to surgery for inoperable patients presenting with a single-lung NSCLC.

Improved hydrogen storage properties of MgH2 by the addition of FeS2 micro-spheres.

The sulfide catalyst is a subject of great interest in developing a MgH2 system as a potential hydrogen storage medium. In this work, FeS2 micro-spheres were successfully prepared by the surfactant-assisted solvothermal method, and later were ball milled with MgH2 to fabricate the MgH2-16.7 wt% FeS2 composite. FeS2 addition could dramatically improve both the hydrogenation and dehydrogenation kinetics, and lower the dehydrogenation temperature of MgH2 as well. The MgH2-16.7 wt% FeS2 composite could absorb 3.71 wt% H2 at 423 K, which is 3.59 times as high as that of the as-milled pure MgH2. The composite started to release hydrogen at 569 K, and it could release 1.24 wt% H2 at 573 K within 1400 s. However, pure MgH2 could only release 0.18 wt% H2 under the identical conditions. Furthermore, the activation energy of hydrogen desorption was reduced to 68.94 kJ mol-1. FeS2 addition also altered the rate-controlling steps and facilitated the H diffusion of MgH2 in the hydrogen absorption process. The synergistic catalytic effects of the in situ formed Fe active species and MgS may contribute to the enhanced hydrogen storage properties of MgH2.

Up-regulation of angiopoietin-2, matrix metalloprotease-2, membrane type 1 metalloprotease, and laminin 5 gamma 2 correlates with the invasiveness of human glioma.

Diffuse infiltration of malignant human glioma cells into surrounding brain structures occurs through the activation of multigenic programs. We recently showed that angiopoietin-2 (Ang2) induces glioma invasion through the activation of matrix metalloprotease-2 (MMP-2). Here, we report that up-regulation of Ang2, MMP-2, membrane type 1-MMP (MT1-MMP), and laminin 5 gamma 2 (LN 5 gamma 2) in tumor cells correlates with glioma invasion. Analyses of 57 clinical human glioma biopsies of World Health Organization grade I to IV tumors displaying a distinct invasive edge and 39 glioma specimens that only contain the central region of the tumor showed that Ang2, MMP-2, MT1-MMP, and LN 5 gamma 2 were co-overexpressed in invasive areas but not in the central regions of the glioma tissues. Statistical analyses revealed a significant link between the preferential expression of these molecules and invasiveness. Protein analyses of microdissected primary glioma tissue showed up-regulation and activation of MT1-MMP and LN 5 gamma 2 at the invasive edge of the tumors, supporting this observation. Concordantly, in human U87MG glioma xenografts engineered to express Ang2, increased expression of MT1-MMP and LN 5 gamma 2, along with MMP-2 up-regulation, in actively invading glioma cells was also evident. In cell culture, stimulation of glioma cells by overexpressing Ang2 or exposure to exogenous Ang2 promoted the expression and activation of MMP-2, MT1-MMP, and LN 5 gamma 2. These results suggest that up-regulation of Ang2, MMP-2, MT1-MMP, and LN 5 gamma 2 is associated with the invasiveness displayed by human gliomas and that induction of these molecules by Ang2 may be essential for glioma invasion.

Overexpression of vascular endothelial growth factor by MCF-7 breast cancer cells promotes estrogen-independent tumor growth in vivo.

Alteration of the phenotype of breast cancers from estrogen-dependent to estrogen-independent growth often leads to the failure of antiestrogenic tumor therapies. We report that overexpression of vascular endothelial growth factor (VEGF) by estrogen-dependent MCF-7 breast cancer cells could abolish estrogen-dependent tumor growth in ovariectomized mice. In the absence of estrogen, MCF-7 VEGF-expressing tumors with increased vessel density showed growth kinetics similar to, or even greater than, that of parental MCF-7 tumors with estrogen supplementation. Overexpression of VEGF by MCF-7 cells or treatment on parental MCF-7 cells with recombinant VEGF also stimulated cell proliferation in culture. Our data suggest that VEGF stimulation of MCF-7 tumor angiogenesis and growth is mediated by both autocrine and paracrine mechanisms.

Angiopoietin-2 induces human glioma invasion through the activation of matrix metalloprotease-2.

A hallmark of highly malignant human gliomas is their infiltration of the brain. We analyzed a large number of primary human glioma biopsies and found high levels of expression of an angiogenic regulator, angiopoietin-2 (Ang2), in the invasive areas, but not in the central regions, of those tumors. In the invasive regions where Ang2 was overexpressed, increased levels of matrix metalloprotease-2 (MMP-2) were also apparent. Consonant with these features, intracranial xenografts of glioma cells engineered to express Ang2 were highly invasive into adjacent brain parenchyma compared with isogenic control tumors. In regions of the Ang2-expressing tumors that were actively invading the brain, high levels of expression of MMP-2 and increased angiogenesis were also evident. A link between these two features was apparent, because stable expression of Ang2 by U87MG cells or treatment of several glioma cell lines with recombinant Ang2 in vitro caused activation of MMP-2 and acquisition of increased invasiveness. Conversely, MMP inhibitors suppressed Ang2-stimulated activation of MMP-2 and Ang2-induced cell invasion. These results suggest that Ang2 plays a critical role in inducing tumor cell infiltration, and that this invasive phenotype is caused by activation of MMP-2.