[Construction and analysis of gene co-expression networks in intracranial aneurysm]

Objective: To analyze the expression microarray data in the public databases of intracranial aneurysms (IA) using bioinformatics, and to provide important information for the study of disease mechanisms. Methods: Gene co-expression network was constructed by weighted gene co-expression network analysis (WGCNA) based on the dataset (GSE75436) and pivot genes were identified. Using the online tool DAVID (Database for Annotation, Visualization, and Integrated Discovery) to perform GO function enrichment and KEGG path analysis on modules highly related to IA. Results: Three IA-related modules were screened out, and 14 pivot genes (COL3A1, SPARC, CDH11, COL5A1, HOPX, CLEC11A, GALNT10, ADAMTS2, CEMIP, KIAA1755, COL11A1, ZIC2, CDKN2A, and LINC00460) in the brown module were identified; the analysis of GO showed that the brown module was mainly enriched in extracellular matrix organization, extracellular matrix organization, cell adhesion and other biological processes; the analysis of KEGG indicated that the brown module involved in ECM-receptor interaction, Focal adhesion, protein digestion and absorption, PI3K-Akt signaling pathway. Conclusion: Based on WGCNA, we identified modular and pivotal genes that are critical to the development of IA, and they may become potential biomarkers and/or therapeutic targets.

Effects of Astragalus glycoprotein on Th17/Treg cells in mice with collagen-induced arthritis

In this study of Th17/Treg cells, the therapeutic effect of Astragalus glycoprotein on collagen-induced arthritis in mice (CIA) was explored, and a basis for the clinical treatment of rheumatoid arthritis is provided. Sixty mice were selected for the establishment of a CIA mouse model, and were then randomly divided into a CIA model group, a hydrocortisone control group, a low, medium, and high dose group of Astragalus glycoprotein, respectively. The same number of control groups with same number of mice was established and after basic immunization, intraperitoneal injections were given once daily for two weeks in the treatment. At the end of the treatment, the mice in each group were selected and the proportion of Th17/Treg cells was detected by flow cytometry. The expression and positive expression of RORt, Foxp3, P-STAT3 and P-STAT5 protein were detected by Western blot and immunohistochemistry. Astragalus glycoprotein was shown to potentially improve the diet and mental state, reduce the arthritis index score and improve the pathological state of synovial membranes in the mice. Moreover, flow cytometry results showed that, compared with the CIA model group, the proportion of Th17 cells in the four other groups of mice decreased, while the proportion of Treg cells increased. This difference was statistically significant (P less than 0.05). From the experiment, the following conclusions were drawn: Astragalus glycoprotein can reduce Th17 cells and their transcription factors in the peripheral blood of CIA mice, up-regulate Treg cells and their transcription factors, and correct the balance of Th17/Treg cells so as to achieve an effective of treatment for CIA mice.

White matter hyperintensity and stroke lesion segmentation and differentiation using convolutional neural networks

White matter hyperintensities (WMH) are a feature of sporadic small vessel disease also frequently observed in magnetic resonance images (MRI) of healthy elderly subjects. The accurate assessment of WMH burden is of crucial importance for epidemiological studies to determine association between WMHs, cognitive and clinical data; their causes, and the effects of new treatments in randomized trials. The manual delineation of WMHs is a very tedious, costly and time consuming process, that needs to be carried out by an expert annotator (e.g. a trained image analyst or radiologist). The problem of WMH delineation is further complicated by the fact that other pathological features (i.e. stroke lesions) often also appear as hyperintense regions. Recently, several automated methods aiming to tackle the challenges of WMH segmentation have been proposed. Most of these methods have been specifically developed to segment WMH in MRI but cannot differentiate between WMHs and strokes. Other methods, capable of distinguishing between different pathologies in brain MRI, are not designed with simultaneous WMH and stroke segmentation in mind. Therefore, a task specific, reliable, fully automated method that can segment and differentiate between these two pathological manifestations on MRI has not yet been fully identified. In this work we propose to use a convolutional neural network (CNN) that is able to segment hyperintensities and differentiate between WMHs and stroke lesions. Specifically, we aim to distinguish between WMH pathologies from those caused by stroke lesions due to either cortical, large or small subcortical infarcts. The proposed fully convolutional CNN architecture, called uResNet, that comprised an analysis path, that gradually learns low and high level features, followed by a synthesis path, that gradually combines and up-samples the low and high level features into a class likelihood semantic segmentation. Quantitatively, the proposed CNN architecture is shown to outperform other well established and state-of-the-art algorithms in terms of overlap with manual expert annotations. Clinically, the extracted WMH volumes were found to correlate better with the Fazekas visual rating score than competing methods or the expert-annotated volumes. Additionally, a comparison of the associations found between clinical risk-factors and the WMH volumes generated by the proposed method, was found to be in line with the associations found with the expert-annotated volumes.

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Robust, fully automatic white matter hyperintensity and stroke lesion segmentation and differentiation

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A novel patch sampling strategy used during CNN training that avoids the introduction of erroneous locality assumptions

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Improved segmentation accuracy in terms of Dice scores when compared to well established state-of-the-art methods

[Effects of hydrogen on the lung damage of mice at early stage of severe burn]

Objective: To investigate the effects of hydrogen on the lung damage of mice at early stage of severe burn. Methods: One hundred and sixty ICR mice were divided into sham injury, hydrogen, pure burn, and burn+ hydrogen groups according to the random number table, with 40 mice in each group. Mice in pure burn group and burn+ hydrogen group were inflicted with 40% total body surface area full-thickness scald (hereafter referred to as burn) on the back, while mice in sham injury group and hydrogen group were sham injured. Mice in hydrogen group and burn+ hydrogen group inhaled 2% hydrogen for 1 h at post injury hour (PIH) 1 and 6, respectively, while mice in sham injury group and pure burn group inhaled air for 1 h. At PIH 24, lung tissue of six mice in each group was harvested, and then pathological changes of lung tissue were observed by HE staining and the lung tissue injury pathological score was calculated. Inferior vena cava blood and lung tissue of other eight mice in each group were obtained, and then content of high mobility group box 1 (HMGB1) and interleukin-6 (IL-6) in serum and lung tissue was determined by enzyme-linked immunosorbent assay. Activity of superoxide dismutase (SOD) in serum and lung tissue was detected by spectrophotometry. After arterial blood of other six mice in each group was collected for detection of arterial partial pressure of oxygen (PaO(2)), the wet and dry weight of lung tissue were weighted to calculate lung wet to dry weight ratio. The survival rates of the other twenty mice in each group during post injury days 7 were calculated. Data were processed with one-way analysis of variance, LSD test and log-rank test. Results: (1) At PIH 24, lung tissue of mice in sham injury group and hydrogen group showed no abnormality. Mice in pure burn group were with pulmonary interstitial edema, serious rupture of alveolar capillary wall, and infiltration of a large number of inflammatory cells. Mice in burn+ hydrogen group were with mild pulmonary interstitial edema, alveolar capillary congestion accompanied by slight rupture and bleeding, and the number of infiltration of inflammatory cells was smaller than that in pure burn group. The lung tissue injury pathological scores of mice in sham injury group, hydrogen group, pure burn group, and burn+ hydrogen group were (0.7±0.5), (0.8±0.5), (6.1±1.0), and (2.8±0.8) points, respectively. The lung tissue injury pathological score of mice in pure burn group was significantly higher than that in sham injury group (P<0.001). The lung tissue injury pathological score of mice in burn+ hydrogen group was significantly lower than that in pure burn group (P<0.001). (2) At PIH 24, the content of HMGB1 and IL-6 in serum and lung tissue of mice in hydrogen group was close to that in sham injury group (with P values above 0.05). The content of HMGB1 and IL-6 in serum and lung tissue of mice in pure burn group was significantly higher than that in sham injury group (with P values below 0.001). The content of HMGB1 and IL-6 in serum and lung tissue of mice in burn+ hydrogen group was significantly lower than that in pure burn group (with P values below 0.001). (3) At PIH 24, the activity of SOD in serum and lung tissue of mice in hydrogen group was close to that in sham injury group (with P values above 0.05). The activity of SOD in serum and lung tissue of mice in pure burn group was significantly lower than that in sham injury group (with P values below 0.001). The activity of SOD in serum and lung tissue of mice in burn+ hydrogen group was significantly higher than that in pure burn group (with P values below 0.001). (4) At PIH 24, there was no statistically significant difference in PaO(2) among the mice in four groups (F=0.04, P>0.05). (5) At PIH 24, the ratios of lung wet to dry weight of mice in sham injury, hydrogen, pure burn, and burn+ hydrogen groups were 3.52±0.22, 3.61±0.24, 7.24±0.32, and 5.21±0.41, respectively. The ratio of lung wet to dry weight of mice in pure burn group was significantly higher than that in sham injury group (P<0.001). The ratio of lung wet to dry weight of mice in burn+ hydrogen group was significantly lower than that in pure burn group (P<0.001). (6) The survival rates of mice in sham injury group and hydrogen group during post injury days 7 were 100%. Compared with those in sham injury group, survival rates of mice in pure burn group from post injury days 3 to 7 were significantly decreased (with P values below 0.05). Compared with those in pure burn group, survival rates of mice in burn+ hydrogen group from post injury days 5 to 7 were significantly increased (with P values below 0.05). Conclusions: Hydrogen can significantly alleviate the infiltration of inflammatory cells and improve the pathological lesions of lung tissue of mice with severe burn. It has the effects of reducing inflammatory reaction and inhibiting oxidative stress, further showing the protective effect on the lung of burn mice.

[A clinical study on the pathogenesis of lung cancer-related cerebral infarction]

Objective: To explore the risk factors for lung cancer-related cerebral infarction. Methods: The hospitalized active lung cancer patients on anti-cancer therapy with no traditional stroke risk factors, who experienced an acute cerebral infarct in the First Affiliated Hospital of Guangxi Medical University from January 2005 to December 2015, were consecutively collected as the LCRS (lung cancer-related stroke) group. The active lung cancer patients without cerebral infarction hospitalized at the same peroid matched with the LCRS group for age and gender were collected as the LC (lung cancer) group. Clinical data from the two groups were analyzed. Results: A total of 139 LCRS patients and 139 LC patients were enrolled in the study, with 110 male and 29 female in each group, and there were no significant difference for the mean age between the LCRS group (52.1±10.4 years old ) and the LC group (52.1±10.1 years old). Two or more acute ischemic lesions of the brain were showed by MRI in most patients in the LCRS group (117 cases, 84.2%). Compared with the LC group, more patients in the LCRS group were found with adenocarcinoma, metastasis, elevated plasma D-dimer, CA125 and CA199 levels [88 cases (63.3%) vs 47 cases (33.8%); 98 cases (70.5%) vs 56 cases (40.3%); (468.38±291.37) μg/L vs (277.59±191.22) μg/L; (221.42±146.34) U/ml vs (106.84±69.97) U/ml; (254.68±185.84) U/ml vs (97.15±63.64) U/ml; with all P<0.001]. By logistic regression analysis of multiple factors, the elevated plasma D-dimer, CA125 and CA199 levels were showed to be independent risk factors for the cerebral infarction (OR=1.003, 95%CI 1.001-1.004; OR=1.006, 95%CI 1.003-1.010; OR=1.011, 95%CI 1.007-1.015). Conclusions: The elevated plasma D-dimer, CA125 and CA199 levels are the risk factors for the lung cancer related cerebral infarction, which may lead to hypercoagulation and induce cerebral infarction eventually.

Dentin Matrix Protein 1 (DMP1): New and Important Roles for Biomineralization and Phosphate Homeostasis

Previously, non-collagenous matrix proteins, such as DMP1, were viewed with little biological interest. The last decade of research has increased our understanding of DMP1, as it is now widely recognized that this protein is expressed in non-mineralized tissues, as well as in cancerous lesions. Protein chemistry studies have shown that the full length of DMP1, as a precursor, is cleaved into two distinct forms: the C-terminal and N-terminal fragments. Functional studies have demonstrated that DMP1 is essential in the maturation of odontoblasts and osteoblasts, as well as in mineralization via local and systemic mechanisms. The identification of DMP1 mutations in humans has led to the discovery of a novel disease: autosomal-recessive hypophosphatemic rickets. Furthermore, the regulation of phosphate homeostasis by DMP1 through FGF23, a newly identified hormone that is released from bone and targeted in the kidneys, sets a new direction for research that associates biomineralization with phosphate regulation.

Post-translational Modifications of SIBLING Proteins and Their Roles in Osteogenesis and Dentinogenesis

The extracellular matrix (ECM) of bone and dentin contains several non-collagenous proteins. One category of non-collagenous protein is termed the SIBLING (Small Integrin-Binding LIgand, N-linked Glycoprotein) family, that includes osteopontin (OPN), bone sialoprotein (BSP), dentin matrix protein 1 (DMP1), dentin sialophosphoprotein (DSPP), and matrix extracellular phosphoglycoprotein (MEPE). These polyanionic SIBLING proteins are believed to play key biological roles in the mineralization of bone and dentin. Although the specific mechanisms involved in controlling bone and dentin formation are still unknown, it is clear that some functions of the SIBLING family members are dependent on the nature and extent of post-translational modifications (PTMs), such as phosphorylation, glycosylation, and proteolytic processing, since these PTMs would have significant effects on their structure. OPN and BSP are present in the ECM of bone and dentin as full-length forms, whereas amino acid sequencing indicates that DMP1 and DSPP exist as proteolytically processed fragments that result from scission of X-Asp bonds. We hypothesized that the processing of DMP1 and DSPP is catalyzed by the PHEX enzyme, since this protein, an endopeptidase that is predominantly expressed in bone and tooth, has a strong preference for cleavage at the NH2-terminus of aspartyl residue. We envision that the proteolytic processing of DMP1 and DSPP may be an activation process that plays a significant, crucial role in osteogenesis and dentinogenesis, and that a failure in this processing would cause defective mineralization in bone and dentin, as observed in X-linked hypophosphatemic rickets.

Transgenic expression of dentin phosphoprotein inhibits skeletal development

Dentin sialophosphoprotein (DSPP) is proteolytically processed into an NH₂-terminal fragment called dentin sialoprotein (DSP) and a COOH-terminal fragment known as dentin phosphoprotein (DPP). These two fragments are believed to perform distinct roles in formation of bone and dentin. To investigate the functions of DPP in skeletal development, we generated transgenic mice to overexpress hemagglutinin (HA)-tagged DPP under the control of a 3.6 kb type I collagen (Col1a1) promoter (designated as Col1a1-HA-DPP). The Col1a1-HA-DPP transgenic mice were significantly smaller by weight, had smaller skeletons and shorter long bones than their wild type littermates, as demonstrated by X-ray radiography. They displayed reduced trabecular bone formation and narrower zones of proliferative and hypertrophic chondrocytes in the growth plates of the long bones. Histological analyses showed that the transgenic mice had reduced cell proliferation in the proliferating zone, but lacked obvious defects in the chondrocyte differentiation. In addition, the transgenic mice with a high level of transgene expression developed spontaneous long bone fractures. In conclusion, overexpressing DPP inhibited skeletal development, suggesting that the balanced actions between the NH₂- and COOH-terminal fragments of DSPP may be required for normal skeletal development.

Repair of dentin defects from DSPP knockout mice by PILP mineralization

Dentinogenesis imperfecta type II (DGI-II) lacks intrafibrillar mineral with severe compromise of dentin mechanical properties. A Dspp knockout (Dspp-/-) mouse, with a phenotype similar to that of human DGI-II, was used to determine if poly-L-aspartic acid [poly(ASP)] in the "polymer-induced liquid-precursor" (PILP) system can restore its mechanical properties. Dentin from six-week old Dspp-/- and wild-type mice was treated with CaP solution containing poly(ASP) for up to 14 days. Elastic modulus and hardness before and after treatment were correlated with mineralization from Micro x-ray computed tomography (Micro-XCT). Transmission electron microscopy (TEM)/Selected area electron diffraction (SAED) were used to compare matrix mineralization and crystallography. Mechanical properties of the Dspp-/- dentin were significantly less than wild-type dentin and recovered significantly (P < 0.05) after PILP-treatment, reaching values comparable to wild-type dentin. Micro-XCT showed mineral recovery similar to wild-type dentin after PILP-treatment. TEM/SAED showed repair of patchy mineralization and complete mineralization of defective dentin. This approach may lead to new strategies for hard tissue repair.

Assessing the safety of outpatient ventral hernia repair: a NSQIP analysis of 7666 patients

PURPOSE

Given the paucity of literature on outpatient ventral hernia repair (VHR), and that assessment of the safety of outpatient surgical procedures is becoming an active area of investigation, we have performed a multi-institutional retrospective analysis benchmarking rates of 30-day complications and readmissions and identifying predictive factors for these outcomes.

METHODS

National surgical quality improvement project data files from 2011 to 2012 were reviewed to collect data on all patients undergoing outpatient VHR during that period. The incidence of 30-day peri-operative complication and unplanned readmission was surveyed. We created a multivariate regression model to identify predictive factors for overall, surgical, and medical complications and unplanned readmissions with proper risk adjustment.

RESULTS

30-day complication and readmission rates in outpatient VHR were acceptably low. 3% of the queried outpatients experienced an overall complication, 2.1% a surgical complication, and 1.1% a medical complication. 3.3% of all patients were readmitted within 30 days. Upon multivariate analysis, predictors of overall complications included age, BMI, history of Chronic Obstructive Pulmonary Disease (COPD), and total operation time, predictors of surgical complications included age, BMI, total operation time, predictors of medical complications included total operation time, and predictors of unplanned readmissions included history of COPD, bleeding disorder, American Society of Anesthesiologists Class 3, 4, or 5, total operation time, and use of the laparoscopic technique.

CONCLUSION

We have demonstrated that the risk of peri-operative morbidity in VHR as granularly defined in our study is low in the outpatient setting. Identification of predictive factors will be important to patient risk stratification.

An in situ hybridization study of perlecan, DMP1, and MEPE in developing condylar cartilage of the fetal mouse mandible and limb bud cartilage

The main purpose of this in situ hybridization study was to investigate mRNA expression of three bone/cartilage matrix components (perlecan, DMP1, and MEPE) in developing primary (tibial) and secondary (condylar) cartilage. Perlecan mRNA expression was first detected in newly formed chondrocytes in tibial cartilage at E13.0, but this expression decreased in hypertrophic chondrocytes at E14.0. In contrast, at E15.0, perlecan mRNA was first detected in the newly formed chondrocytes of condylar cartilage; these chondrocytes had characteristics of hypertrophic chondrocytes, which confirmed the previous observation that progenitor cells of developing secondary cartilage rapidly differentiate into hypertrophic chondrocytes. DMP1 mRNA was detected in many chondrocytes within the lower hypertrophic cell zone in tibial cartilage at E14.0. In contrast, DMP1 mRNA expression was only transiently detected in a few chondrocytes of condylar cartilage at E15.0. Thus, DMP1 may be less important in the developing condylar cartilage than in the tibial cartilage. Another purpose of this study was to test the hypothesis that MEPE may be a useful marker molecule for cartilage. MEPE mRNA was not detected in any chondrocytes in either tibial or condylar cartilage; however, MEPE immunoreactivity was detected throughout the cartilage matrix. Western immunoblot analysis demonstrated that MEPE antibody recognized two bands, one of 67 kDa and another of 59 kDa, in cartilage-derived samples. Thus MEPE protein may gradually accumulate in the cartilage, even though mRNA expression levels were below the limits of detection of in situ hybridization. Ultimately, we could not designate MEPE as a marker molecule for cartilage, and would modify our original hypothesis.