Gut microbiota composition and bone mineral loss-epidemiologic evidence from individuals in Wuhan, China

We explored the association between gut microbiota composition and bone mineral loss in Chinese elderly people by high-throughput 16S ribosomal RNA (rRNA) gene sequencing. Compared with controls, a smaller number of operational taxonomic units (OTUs), several taxa with altered abundance, and specific functional pathways were found in individuals with low-bone mineral density (BMD).

INTRODUCTION

Gut microbiota plays important roles in human health and associates with a number of diseases. However, few studies explored its association with bone mineral loss in human.

METHODS

We collected 102 fecal samples from each eligible individual belonging to low-BMD and control groups for high-throughput 16S rRNA gene sequencing.

RESULTS

The low-BMD individuals had a smaller number of OTUs and bacterial taxa at each level. At the phylum level, Bacteroidetes were more abundant in the low-BMD group; Firmicutes were enriched in the control group; Firmicutes and Actinobacteria positively correlated and Bacteroidetes negatively correlated with the BMD and T-score in all subjects. At the family level, the abundance of Lachnospiraceae in low-BMD individuals reduced and positively correlated with BMD and T-score; meanwhile, BMD increased with increasing Bifidobacteriaceae. At the genus level, low-BMD individuals had decreased proportions of Roseburia compared with control ones (P < 0.05). Roseburia, Bifidobacterium, and Lactobacillus positively correlated with BMD and T-score. Furthermore, BMD increased with rising abundance of Bifidobacterium. Functional prediction revealed that 93 metabolic pathways significantly differed between the two groups (FDR-corrected P < 0.05). Most pathways, especially pathways related to LPS biosynthesis, were more abundant in low-BMD individuals than in control ones.

CONCLUSIONS

Several taxa with altered abundance and specific functional pathways were discovered in low-BMD individuals. Our findings provide novel epidemiologic evidence to elucidate the underlying microbiota-relevant mechanism in bone mineral loss and osteoporosis.

[The effect of air test and methylene blue perfusion test on detecting the quality of anastomosis during laparoscopic rectal cancer excision (Dixon)]

Objective: To investigate the feasibility and safety of air test (AT) and methylene blue perfusion test (MBPT) to detect the quality of the anastomosis in laparoscopic rectal cancer excision (Dixon), and compare the two approaches. Methods: AT is performed by filling the pelvis with saline solution and insufflating the rectum with air through a size 22 G balloon catheter (Foley). MBPT is carried out by surrounding clean sponges around anastomosis and injecting methylene blue solution into the rectum as like as AT. The balloon catheter connected manometer,ensuring the pressure in rectum can reach 40 cmH(2)O during AT and MBPT. The presence of air bubbles and overt blue-stained spillage indicated anastomotic leaks which are were resolved during surgery. All 28 patients undergoing laparoscopic rectal excision received both AT and MBPT intraoperatively in a randomized fashion. The integrity of the anastomosis, postoperative vital signs, blood examination, drainage and postoperative imaging were analyzed. Results: All 28 patients received both tests successfully with no adverse event. MBPT Level 1 was detected in 15 cases, level 2 in 8 cases, level 3 in 5 cases. No MBPT level 4 was observed. AT level 1 was detected in 22 cases, level 2 in 5 cases, level 3 in 1 cases. No AT level 4 was founded. Three cases were diagnosed with postoperative anastomotic leakage (3/28, 10.71%), of which 2 cases were Grade B [definition and grading proposed by the international study group of rectal cancer (ISREC) in 2010]. One case was Grade C. The positive rate of MBPT was superior to AT (the McNemar testing, P<0.01). Conclusions: The two intraoperative tests are both technically feasible and safe. Compared to AT, MBPT has the advantage of localizing the leak site with a higher positive accuracy, and represents a promising standardized approach for intraoperative test of the anastomosis quality. Intraoperative repair is absolutely helpful for the level 3 and 4 intraoperative tests.

Simplified colonic dialysis with hemodialysis solutions delays the progression of chronic kidney disease

BACKGROUND

The colon plays a vital role in the disposal of nitrogenous waste products. Therefore, the colon may provide a therapeutic target for managing chronic kidney disease (CKD).

AIM

To evaluate the efficacy of a simplified model of colonic dialysis with hemodialysis solutions (SCD) to delay the progression of stages 3-5 CKD.

DESIGN

Retrospective study.

METHODS

We retrospectively analyzed 178 stages 3-5 CKD patients who did or did not receive SCD (SCD group, n = 88; control group, n = 90). The follow-up was 36 months. The outcome of CKD progression was defined as a decrease in 50% or more in estimated glomerular filtration rate, starting hemodialysis or peritoneal dialysis or undergoing transplantation. The Kaplan-Meier analysis was used to compare CKD progression between SCD and control groups as well as between subgroups at different CKD stages. Cox proportional hazard models adjusted for patients' characteristics were used to examine the association between SCD and the outcome.

RESULTS

For all patients, the outcome was significantly better in SCD group compared to control group (P < 0.05). The results were similar in the subgroups of patients at stage 4 (P = 0.001) and stage 5 (P = 0.000), but not in the subgroup of patients at stage 3 (P = 0.121). For all patients, SCD was associated with a lower risk of CKD progression after adjusted for patients' characteristics (adjusted hazard ratio, 0.373; 95% confidence interval, 0.201-0.694; P 0.002).

CONCLUSION

SCD is an effective supplementary therapy to delay the progression of stages 4-5 CKD.

[Real-world research on cervical cancer screening program and effect evaluation for Chinese population]

Objective: To evaluate the actual efficacy of cervical cancer and precancerous lesions screening approaches in real-world regions with different economic levels in China. Methods: The demonstrative application and effect evaluation of cervical cancer screening program were conducted in 21 hospitals nationwide from 2015 to 2018. Multi-stage sampling method was adopted to divide the country into 7 large areas according to geographical location. Two to four screening sites of two types of cancer (cervical cancer and breast cancer) were selected in each area, and the grassroots screening sites were implemented under the guidance of superior hospitals. In rural areas, women were initially screened using cytology, human papillomavirus (HPV) testing and visual inspection. The women with positive cytology or visual inspection were referred for colposcopy, and the women with positive HPV infection were randomly referred for reflex cytology or visual inspection, or direct colposcopy examination. In urban areas, women were primarily randomized into cytology or HPV testing groups. The women with abnormal cytology or positive HPV 16/18 infection were directly referred for colposcopy examination, whereas the women with positive infection of the other 12 high-risk subtypes of HPV were referred for reflex cytology or colposcopy. All of recruited women would be follow-up and screened by the baseline screening techniques in the third year while the positive women underwent colposcopy examination. The positive rates, referral rates, the detection rates of grade 2 and above of cervical intraepithelial neoplasia (CIN 2+ ) were compared. Results: A total of 63 931 women were recruited at the baseline. Among them, 11 rural sites included 33 823 women: 15 577, 11 157 and 7 089 women were screened by HPV testing, visual inspection via acetic acid or Lugol's iodine (VIA/VILI) and cytology, respectively. Additionally, 30 108 women were from 10 urban sites: 9 907 and 20 201 women were screened by cytology and HPV subtyping, respectively. The HPV positive rate for urban women was 9.34%, whereas that for rural women was 12.53%. The abnormal rate of cytology for urban women was 5.63%, and that for rural women was 4.24%. The positive rate of VIA/VILI in the rural women was 12.25% Furthermore, the detection rate of CIN2+ at the baseline was 0.56%, and that was statistically higher in HPV-positive group than cytology-positive group (P<0.05). Conclusions: All of screening sites completed the baseline screening tasks as expected. The prevalence of HPV infection is higher in rural women than urban women. The performance of HPV testing is better than cytology for detecting CIN2+ cases. This real-world demonstration study provides evidences for cervical cancer prevention and control in different regions.

Genomewide analysis of 6-methyladenine DNA in peripheral blood mononuclear cells of systemic lupus erythematosus

Aim

The aim of this paper is to explore the expression of 6-methyladenine (6mA) DNA and to elucidate its gene regulation role in systemic lupus erythematosus (SLE).

Methods

Twenty SLE patients and 20 normal control healthy individuals (HCs) were included in this study. Genomic DNA was isolated from peripheral blood mononuclear cells and subsequently underwent 6mA-immunoprecipitation-sequencing (6mA-IP-Seq) after DNA quality control and 6mA precipitation. Bioinformation analysis was applied to the raw data comparing 6mA levels between SLE patients and HCs.

Results

We identified 5462 hypermethylation and 431 hypomethylation genes in PBMCs of individuals with SLE, which indicated that a high level of 6mA participates in the pathogenesis of SLE. Gene ontology analysis revealed that hypermethylation genes might regulate the inflammatory process, which has been well documented in the pathogenesis of SLE.

Conclusion

6mA may be involved in the initial development of SLE, which may lead to its potential use as an early diagnostic marker and therapeutic target.

A comprehensive evaluation of 181 reported CHST6 variants in patients with macular corneal dystrophy

Macular corneal dystrophy (MCD) is an autosomal recessive disease featured by bilateral progressive stromal clouding and loss of vision, consequently necessitating corneal transplantation. Variants in CHST6 gene have been recognized as the most critical genetic components in MCD. Although many CHST6 variants have been described until now, the detailed mechanisms underlying MCD are still far from understood. In this study, we integrated all the reported CHST6 variants described in 408 MCD cases, and performed a comprehensive evaluation to better illustrate the causality of these variants. The results showed that majority of these variants (165 out of 181) could be classified as pathogenic or likely pathogenic. Interestingly, we also identified several disease causal variants with ethnic specificity. In addition, the results underscored the strong correlation between mutant frequency and residue conservation in the general population (Spearman's correlation coefficient = -0.311, P = 1.20E-05), thus providing potential candidate targets for further genetic manipulation. The current study highlighted the demand of further functional investigations to evaluate the causality of CHST6 variants, so as to promote earlier accurate diagnosis of MCD and future development of potential targets for genetic therapy.

Differentially expressed long non-coding RNAs and the prognostic potential in colorectal cancer

Colorectal cancer (CRC) is a disease with high incidence, especially in developed countries. Long non-coding RNAs (lncRNAs) are new research hotspots for their vital roles in regulating gene expression. This study aims to investigate the prognostic value of lncRNAs in CRC patients. A total of 21 cancer-related lncRNAs were detected by PCR array to reveal their expression changes in CRC tissue. A 120-week-long follow-up was performed in 30 CRC patients to analyze the relationship between lncRNA levels and CRC prognosis. Most of the 21 lncRNAs were differentially expressed in CRC tissue compared to the adjacent normal tissue, among which seven lncRNAs were significantly changed: AFAP1-AS1, BCAR4, H19, HOXA-AS2, MALAT1 and PVT1 were up-regulated, and ADAMTS9-AS2 was down-regulated in CRC tissue samples. No obvious correlation was found between lncRNA levels and the age, gender, tumor size or TNM stage of these patients. Log-rank test indicated that higher levels of AFAP1-AS1, BCAR4, H19, HOXA-AS2, MALAT1 or PVT1 and lower level of ADAMTS9-AS2 might predict the poor prognosis of CRC patients. This study suggests the potential value of the seven lncRNAs in the prognosis of CRC, providing reference information for future research on CRC prognostic and treatment strategy.

Calcitriol inhibits ROS-NLRP3-IL-1β signaling axis via activation of Nrf2-antioxidant signaling in hyperosmotic stress stimulated human corneal epithelial cells

Purpose

The activation of ROS-NLRP3-IL-1β signaling axis induced by hyperosmotic stress (HS) has been recognized as a key priming stage of epithelial inflammation in dry eye pathogenesis. The current study aims to investigate whether calcitriol, the active metabolite of vitamin D₃, could protect cells against HS-induced inflammation through modulating this critical step.

Methods

Human corneal epithelial cells (iHCECs) were cultured in hyperosmotic medium (450 mOsM) with various concentrations of calcitriol. Small interfering RNA (siRNA) was used to knock down the expression of vitamin D receptor (VDR) in iHCECs. NLRP3 activation and IL-1β generation were detected by RT-qPCR or ELISA, respectively. Oxidative stress markers including ROS and 8-OHdG were examined by fluorometric analysis. The nuclear translocation of NRF2 was assessed by western blotting.

Results

Calcitriol could protect cells against HS-induced injury through inhibiting ROS-NLRP3-IL-1β signaling axis. Calcitriol remarkably suppressed the expression of NLRP3 inflammasome related genes and the production of IL-1β in cells that were exposed to HS. It could also significantly attenuate HS-induced oxidative stress, shown as the reduced intracellular ROS generation and 8-OHdG staining cells after calcitriol treatment. Calcitriol induced the translocation of NRF2 to the nucleus, and thereby triggered the expression of several antioxidant enzymes.

Conclusion

The current study indicated that calcitriol could inhibit the priming stage of HS-induced cellular inflammation, highlighting its potential capacity to prevent and mitigate dry eye related corneal inflammation at an earlier stage.

•

The activation of ROS-NLRP3-IL-1β signaling axis is a key priming stage of epithelial inflammation in dry eye pathogenesis.

•

Calcitriol could protect cells against HS-induced cytotoxicity through inhibiting the ROS-NLRP3-IL-1β signaling axis.

•

The protective effect of calcitriol is associated with the activation of the NRF2-antioxidant signaling.

[The function-structure impairment pattern of optic nerves in primary open-angle glaucoma and normal-tension glaucoma]

Objective: To investigate the characteristics of impairment of the visual field (VF) and retinal nerve fiber layer (RNFL) and the differences of progression pattern of early, middle and late stages of primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG) , and to analyze the correspondence of structure and function. Methods: Cross-sectional study. POAG patients, NTG patients and healthy volunteers who were enrolled from February 2008 to May 2017 at Department of Ophthalmology, Eye & ENT Hospital of Fudan University, underwent basic ophthalmic examination, Humphrey central 24-2 threshold test and optical coherence tomography. Patients were divided into early, middle and late stages according to the mean defect (MD) index of the VF test. According to the RNFL distributional characteristics, the pattern deviation map and RNFL were divided into 6 sectors. The differences of each sector's MD and RNFL thickness in the healthy group and groups of patients at 3 stages were analyzed using the Kruskal-Wallis test, and the correlation of MD and RNFL thickness of each sector was analyzed using the Pearson coefficient. Results: In the POAG group, there were 84 cases (84 eyes) including 35 eyes of early stage, 20 eyes of middle stage and 29 eyes of late stage, with a male/female ratio of 43∶41, aged (45±15) years. In the NTG group, 69 cases (69 eyes) included 30 eyes of early stage, 20 eyes of middle stage and 19 eyes of late stage, with a male/female ratio of 33∶36, aged (49±13) years. The control group had 23 cases (23 eyes), with a male/female ratio of 16∶17 and an age of (44±10) years. There was no significant difference in male/female ratio, age or best corrected visual acuity among the three groups. (1) In the middle stage of POAG, the VF defects of inferior hemi-fields were more severe than the superior (t=21.62, P=0.000), which was opposite to the late stage of POAG (t=-3.28, P=0.003). In each stage of NTG, there was no significant difference between two hemi-fields. In the control group, the MD values(antilog) of VF in the superior peripheral arch (PEA), superior paracentral arch (PAA), inferior PEA and PAA, temporal and central regions were 0.87 (0.63-1.11)/L, 0.74 (0.61-0.83)/L, 0.72 (0.55-0.97)/L, 0.65 (0.51-0.87)/L, 0.69 (0.57-0.97)/L, and 0.82 (0.54-0.93)/L, respectively. The sectoral MD values in the VF sectors of POAG were significant compared with the control group (P<0.05): superior PAA for early stage [0.61 (0.18-0.92)/L, H=21.58], superior PEA and PAA for middle stage [0.61 (0.15-0.87)/L, 0.21 (0.00-0.78)/L, H=25.99, 34.91], superior PEA and PAA, inferior PEA and PAA for late stage [0.01 (0.00-1.13)/L, 0.00 (0.00-0.76)/L, 0.41 (0.00-1.07)/L, 0.21 (0.00-0.95)/L, H=46.27, 54.19, 25.64, 28.10]. With the aggravation of POAG, superior PAA had the largest reduction percentage of sectoral MD. The sectoral MD values in the VF sectors of NTG were significant compared with the control group (P<0.05): superior PAA for early stage [0.54 (0.19-0.80)/L, H=20.93], superior PAA for middle stage [0.60 (0.02-1.01)/L, H=22.13], superior PEA and PAA, inferior PEA and PAA for late stage [0.33 (0.00-0.90)/L, 0.05 (0.00-0.92)/L, 0.16 (0.01-0.87)/L, 0.64 (0.02-1.10)/L, H=37.66, 42.78, 35.15, 37.15]. With the aggravation of NTG, the largest reduction percentage of sectoral MD was found in superior PAA at the beginning but in inferior PAA at last. (2) The RNFL thickness of the control group in Region 1NI, 2TI, 3NS, 4TS, 5N, and 6T was 112.76 (63.54-150.99) μm, 134.89 (89.44-198.55) μm, 96.52 (57.32-158.79) μm, 120.96 (69.25-148.48) μm, 71.85 (65.03-95.47) μm, and 66.24 (55.44-90.97) μm, respectively. The sectoral thickness in the RNFL sectors of POAG were significant compared with the control group (P<0.05): 2TI for early stage [109.17 (43.77-173.86) μm, H=31.50], 1NI, 2TI and 4TS for middle stage [71.54 (49.92-94.98) μm, 62.92 (42.33-102.73) μm, 84.20 (45.98-120.13) μm, H=38.91, 49.89, 30.60], 1NI, 2TI, 3NS, 4TS, 5N and 6T for late stage [61.76 (39.32-97.99) μm, 59.59 (42.80-108.69) μm, 67.28 (42.56-117.96) μm, 65.16 (41.96-138.02) μm, 59.45 (21.04-78.48) μm, 53.74 (27.88-92.71) μm, H=52.76, 55.06, 35.76, 41.72, 41.32, 29.93]. With the aggravation of POAG, at the beginning 2TI had the largest reduction percentage of RNFL thickness but 4TS had it at last. The sectoral thickness in the RNFL sectors of NTG were significantly different from the control group (P<0.05): 2TI for early stage [78.97 (47.77-131.45) μm, H=28.86], 1NI, 2TI, 3NS and 4TS for middle stage [61.46 (49.69-97.38) μm, 74.51 (40.25-135.16) μm, 86.36 (42.70-105.06) μm, 83.60 (54.75-117.35) μm, H=38.76, 35.64, 22.47, 24.14], 1NI, 2TI, 3NS, 4TS and 6T for late stage [61.45 (49.09-92.64) μm, 54.35 (37.40-102.62) μm, 63.72 (28.68-105.55) μm, 61.00 (44.92-108.49) μm, 50.33 (35.62-82.09) μm, H=42.56, 51.50, 36.11, 47.44, 25.50]. With the aggravation of NTG, the sector with the largest reduction percentage of thickness changed from 2TI to NI and 4TS. (3) The VF superior PAA-RNFL 2TI had the highest Pearson correlation coefficient in POAG (r=0.630, P<0.001), while it was the inferior PAA-4TS in NTG (r=0.645, P<0.001). Conclusions: The impairment patterns of VF and RNFL in each stage of POAG and NTG are distinctly different from certain rules of aggravation. The sector with the strongest correlation of function-structure is the VF superior PAA-RNFL inferior temporal sector in POAG and inferior PAA-superior temporal sector in NTG. (Chin J Ophthalmol, 2018, 54: 811-819).

[Comparative analysis of anatomic and non-anatomic hepatectomy for single small hepatocellular carcinoma with microvascular invasion]

Objective: To compare the efficacy and safety of anatomic hepatectomy and non-anatomic hepatectomy in the treatment of single small Hepatocellular carcinoma with MVI. Methods: The clinical data of 84 patients with single small Hepatocellular carcinoma with MVI in Beijing Chaoyang Hospital between January 2008 and December 2013 were retrospectively analyzed. Patients undergoing anatomical hepatectomy were enrolled in the AR group, and the patients undergoing non-anatomic hepatectomy were enrolled in the NR group. The efficacy and survival rate of the two groups were compared. Results: (1) Operation time, numbers of patients with volume of intraoperative blood loss ≥300 ml and number of patients with blood transfusion were (170±41)minutes, 8, 7 in the AR group and (148±35)minutes, 19, 18 in the NR group, respectively, with statistically significant differences between the 2 groups (P<0.05). (2) The 1-year, 2-year and 3-year overall survival rate were 85.7%, 68.6%, 57.1% in the AR group and 79.6%, 53.1%, 42.9% in the NR group, respectively. The 1-year, 2-year and 3-year progression-free survival rate were 80.0%, 62.9%, 51.4% in the AR group and 71.4%, 49.0%, 38.8%, in the NR group, respectively. There were statistically significant differences between the 2 groups both in the overall survival rate and the progression-free survival rate (P<0.05). (3) Prognostic factors analysis of HCC patients with MVI: result of univariate analysis showed that maximum diameter of tumor and surgical procedures were relative factors affecting overall survival and progression-free survival of HCC patients with MVI, AFP level was relative factors affecting progression-free survival of HCC patients with MVI, with statistically significant differences (P<0.05). Result of multivariate analysis showed that maximum diameter of tumor between 3.0 and 5.0 cm and non-anatomic liver resection were independent factors affecting poor overall survival and progression-free survival of HCC patients with MVI, and AFP≥20 μg/L and total bilirubin ≥20 μmol/L were independent factors affecting poor progression-free survival of HCC patients with MVI, with a statistically significant differences (P< 0.05). Conclusion: Anatomic hepatectomy for patients with single small hepatocellular carcinoma with microvascular invasion has better clinical efficacy and safety.

Functional relevance for central cornea thickness-associated genetic variants by using integrative analyses

Background

The genetic architecture underlying central cornea thickness (CCT) is far from understood. Most of the CCT-associated variants are located in the non-coding regions, raising the difficulty of following functional characterizations. Thus, integrative functional analyses on CCT-associated loci might benefit in overcoming these issues by prioritizing the hub genes that are located in the center of CCT genetic network.

Methods

Integrative analyses including functional annotations, enrichment analysis, and protein-protein interaction analyses were performed on all reported CCT GWAS lead SNPs, together with their proxy variants. Functional annotations were conducted by CADD, GWAVA, and Eigen. Enrichment analyses for CCT-associated genes were performed using ToppGene suite. Protein-protein interaction network and gene co-expression analyses were performed by GeneMANIA.

Results

Functional annotations prioritized eight genes (ADAMSTS6, ARID5B, FOXO1, AKAP13, COL4A3, COL8A2, TBL1XR1, and KCMB2) harboring SNPs with strong evidence of regulatory potential. It was also shown that CCT-associated genes were significantly enriched in collagen-related pathways and the phenotype of keratoconus, and some of them were found to be involved in one interaction network.

Conclusion

This study revealed the hub genes that were located in the center of CCT genetic network and provided a new insight into the genetic regulation underlying CCT GWAS findings.

MiR-21 promotes pterygium cell proliferation through the PTEN/AKT pathway

Purpose

To evaluate the effect of the overexpression of miR-21 on the properties of pterygium and examine whether miR-21 promotes the proliferation of pterygium cells through targeting the PTEN/AKT signaling pathway.

Methods

Information regarding patient gender, age, and pterygium severity was gathered. Expression of miR-21 was obtained through examination of excised pterygium tissues and superior conjunctiva tissues with real-time PCR. Human pterygium fibroblasts (HPFs) were obtained from pterygium surgery and subjected to primary culture. The HPF cell lines were divided into a negative control group, an miR-21 inhibitor group, and an miR-21 inhibitor + VO-Ohpic trihydrate group, and then the cell viability and apoptosis and the expression of PTEN and AKT were examined.

Results

Fifty-eight subjects with unilateral primary pterygium were included. An increase in the miR-21 levels in pterygium tissue was evident compared with that in the paired normal conjunctival tissues (independent-samples t test, p<0.01). As the severity of the pterygium increased, the miR-21 levels increased (p=0.004, rs=0.373, Spearman's rank correlation coefficient). The miR-21 inhibitor suppressed the proliferation and induced apoptosis of HPF cells through increasing the PTEN expression, and further decreasing the expression of p-AKT, which could be reversed by the PTEN inhibitor VO-Ohpic trihydrate.

Conclusions

Aberrant miR-21 overexpression in the pterygium could target PTEN, which contributes to abnormal proliferation of the HPF cells through depressing the PTEN/AKT pathway. The results also suggested the potential of miR-21 and the PTEN/AKT pathway as a novel therapeutic strategy for pterygium.

IFN-γ Regulates the Expression of MICA in Human Corneal Epithelium Through miRNA4448 and NFκB

Purpose

Major histocompatibility complex class I-related chain A (MICA), a non-classical major histocompatibility complex molecule, can stimulate or co-stimulate CD8+ T cells or natural killer (nk) cells, thus affecting cornea allograft survival. This study investigated IFN-γ regulation of MICA expression levels in human corneal epithelium by miRNA4448.

Methods

MICA expression levels in human corneal epithelial cells (HCECs) stimulated with IFN-γ were detected by qRT-PCR and an enzyme-linked immunosorbent assay, and differential miRNA expression levels were measured. qRT-PCR, Western blotting, and immunofluorescence staining revealed nuclear factor kappa B (NFκB)/P65 expression in IFN-γ-treated and miRNA4448-overexpressed HCECs. A luciferase reporter assay was used to predict the interaction between NFκB and MICA. Additionally, HCECs were transfected with MICA plasmid or treated with IFN-γ and NKG2D-mAb and cocultured with NK cells and CD8+ T cells. Cell apoptosis was measured using Annexin V/PI staining. qRT-PCR detected the expression of anti-apoptosis factor Survivin and apoptosis factor Caspase 3 in MICA-transfected and IFN-γ-treated HCECs after co-culturing with NK cells and CD8+ T cells.

Results

IFN-γ (500 ng/ml, 24 h) upregulated MICA expression in HCECs in vitro. Among six differentially expressed microRNAs, miRNA4448 levels decreased the most after IFN-γ treatment. The overexpression of miRNA4448 decreased MICA expression. miRNA4448 downregulated NFκB/P65 expression in IFN-γ-induced HCEC, and it was determined that NFκB/P65 directly targeted MICA by binding to the promotor region. A coculture with NK cells and CD8+ T cells demonstrated that MICA overexpression enhanced HCEC apoptosis, which could be inhibited by NKG2D-mAb. Simultaneously, Survivin mRNA expression decreased and Caspase3 mRNA expression increased upon the interaction between MICA and NK (CD8+ T) cells in HCECs.

Conclusion

IFN-γ enhances the expression of MICA in HCECs by modulating miRNA4448 and NFκB/P65 levels, thereby contributing to HCEC apoptosis induced by NK and CD8+ T cells. This discovery may lead to new insights into the pathogenesis of corneal allograft rejection.

Clinical application of protein biomarkers in lupus erythematosus and lupus nephritis

Systemic lupus erythematosus (SLE) is a type of autoimmune disease that damages multiple organs, including the heart, joints, liver and kidneys. The main characteristics of SLE are the deposition of circulating autoantibodies; autoantigen complexes in the renal system; and abnormal expression of complements, cytokines and chemokines. Lupus nephritis (LN) is the most serious manifestation of SLE and is characterized by inflammation of the kidney. This review summarizes recent clinical applications of protein biomarkers including autoantibodies, complements, cytokines and chemokines and some new protein biomarkers in SLE and LN. The clinical differential diagnosis of protein biomarkers related to prognosis and diagnosis is discussed and highlighted. Protein biomarkers play crucial roles in the study of SLE and LN. Useful biomarkers will provide insights into effective treatments for these diseases.

Higher Incidence of Renal Allograft Glomerulonephritis in Living-Related Donor Kidney Transplantation

Glomerulonephritis recurrence has emerged as one of the leading causes of allograft loss. We aimed to investigate the effect of living-related and deceased donation on the incidence of renal allograft glomerulonephritis and its effect on renal allograft survival.

METHODS

Adult renal allograft recipients with primary glomerulonephritis were enrolled. Transplantation date was from Feb 2004 to Dec 2015. Exclusion criteria included combined organ transplantation, structural abnormality, diabetic nephropathy, hypertension nephropathy, obstructive nephropathy, and primary uric acid nephropathy. The incidence of biopsy-proven allograft glomerulonephritis was compared between the living-related donor group and the deceased donor group. Graft survival was assessed with Kaplan-Meier method, and Cox proportional hazard model was used to evaluate the effect of posttransplant glomerulonephritis on graft outcome.

RESULTS

There were 525 living-related donor kidney transplant recipients (LRKTx) and 456 deceased donor kidney transplant recipients (DDKTx) enrolled. The incidence of IgA nephropathy was 8.8% in the LRKTx group and 1.3% in the DDKTx group (P < .001); the incidence of focal segmental glomerulosclerosis (FSGS) was 3.8% in the LRKTx group and 1.5% in the DDKTx group (P = .03). FSGS increased the risk of graft failure compared with non-FSGS (hazard ratio [HR], 3.703 [1.459-9.397]; P = .006). IgA nephropathy increased the risk of graft failure by over 5 times 5 years after kidney transplantation compared with non-IgA nephropathy, but it did not affect early allograft survival (HR for ≥5 years, 6.139; 95% CI, 1.766-21.345; P = .004; HR for <5 years, 0.385 [0.053-2.814]; P = .35).

CONCLUSIONS

Higher incidence of IgA nephropathy and FSGS in renal allograft was observed in living-related donor kidney transplantation compared with deceased donor kidney transplantation. De novo or recurrent IgA nephropathy and FSGS impaired long-term renal allograft survival.

Analysis of the correlation between non-alcoholic fatty liver disease and bone metabolism indicators in healthy middle-aged men

OBJECTIVE

To investigate the relationship between bone metabolic indicators and non-alcoholic fatty liver disease (NAFLD) in healthy middle-aged men.

PATIENTS AND METHODS

The bone metabolic indicators of 232 healthy middle-age men with NAFLD (NAFLD group) and 308 healthy controls without fatty liver (Control group) were measured, including non-collagenous osteocalcin, the procollagen type 1 N-terminal propeptide (P1NP), beta-C-terminal telopeptide of type I collagen (β-CTX). The Student's t-test was used to analyze the differences in the bone metabolic indicators, age, clinical data, biochemical indicators, and the indicators of glucose and lipid metabolism between the two groups. The correlation of fatty liver-related indicators was detected using the logistic regression analysis.

RESULTS

The body mass index (BMI), diastolic blood pressure, and heart rate in NAFLD group were significantly higher than those in Control group. Among the indicators of glucose and lipid metabolism in NAFLD group, the levels of blood glucose [fasting plasma glucose, postprandial blood glucose and hemoglobin A1c (HbA1c)] were significantly higher than those in Control group. In addition, the insulin resistance and secretion indexes were also significantly higher than those in Control group. The levels of lipid metabolic indicators such as triglyceride were higher, but high-density lipoprotein cholesterol was lower than that in Control group. From logistic regression analysis, the BMI, Homeostasis model assessment (HOMA)-β, HOMA-IR, HbA1c and P1NP were positively associated with the occurrence of NAFLD.

CONCLUSIONS

The bone metabolic indicator P1NP might be a potential predicator for the diagnosis of NAFLD in clinical application.

Shell-binary nanoparticle materials with variable electrical and electro-mechanical properties

Nanoparticle (NP) materials with the capability to adjust their electrical and electro-mechanical properties facilitate applications in strain sensing technology. Traditional NP materials based on single component NPs lack a systematic and effective means of tuning their electrical and electro-mechanical properties. Here, we report on a new type of shell-binary NP material fabricated by self-assembly with either homogeneous or heterogeneous arrangements of NPs. Variable electrical and electro-mechanical properties were obtained for both materials. We show that the electrical and electro-mechanical properties of these shell-binary NP materials are highly tunable and strongly affected by the NP species as well as their corresponding volume fraction ratio. The conductivity and the gauge factor of these shell-binary NP materials can be altered by about five and two orders of magnitude, respectively. These shell-binary NP materials with different arrangements of NPs also demonstrate different volume fraction dependent electro-mechanical properties. The shell-binary NP materials with a heterogeneous arrangement of NPs exhibit a peaking of the sensitivity at medium mixing ratios, which arises from the aggregation induced local strain enhancement. Studies on the electron transport regimes and micro-morphologies of these shell-binary NP materials revealed the different mechanisms accounting for the variable electrical and electro-mechanical properties. A model based on effective medium theory is used to describe the electrical and electro-mechanical properties of such shell-binary nanomaterials and shows an excellent match with experiment data. These shell-binary NP materials possess great potential applications in high-performance strain sensing technology due to their variable electrical and electro-mechanical properties.

Non-alcoholic fatty liver disease is associated with stroke severity and progression of brainstem infarctions

BACKGROUND AND PURPOSE

Non-alcoholic fatty liver disease (NAFLD) is closely correlated to visceral obesity, dyslipidaemia, insulin resistance and type 2 diabetes mellitus. We sought to assess the association between a specific stroke subgroup, brainstem infarctions (BSIs) and NAFLD. Furthermore, we evaluated whether NAFLD is an independent risk factor in patients with BSIs.

METHODS

Non-alcoholic fatty liver disease was assessed in 306 patients with radiologically confirmed BSIs via liver ultrasound. Differences between patients with and without NAFLD were compared. Data associated with stroke severity and progression after admission were collected.

RESULTS

Non-alcoholic fatty liver disease was found in 130 (42.5%) patients with acute BSIs; 58 (19.0%) had National Institutes of Health Stroke Scale scores >7 and 57 (18.6%) had progression after admission. Initial National Institutes of Health Stroke Scale scores, incidence of progression and stroke severity, and modified Rankin Scale scores at discharge were significantly higher in patients with NAFLD than in those without NAFLD. NAFLD was associated with stroke severity [Cox regression: hazard ratio (HR), 2.243; 95% confidence interval (CI), 1.254-4.013, P < 0.01]. This risk remained statistically significant after controlling for age, gender, diabetes mellitus and C-reactive protein (HR, 2.327; 95% CI, 1.252-4.324, P < 0.01). In addition, NAFLD was associated with progression (HR, 2.155; 95% CI, 1.201-3.865, P < 0.05) and remained significant after controlling for age, gender, diabetes mellitus, fibrinogen and C-reactive protein (HR, 2.378; 95% CI, 1.260-4.486, P < 0.01).

CONCLUSIONS

These results suggest that NAFLD is a potential risk factor when evaluating the severity and progression of acute BSIs. This relationship is independent of classic risk factors and metabolic syndrome features.

[Mechanism of cross talk between tissue factor/active coagulation factor VII and epidermal growth factor receptor signalings in colon cancer cells in culture]

OBJECTIVE

To preliminarily verify the cross talk between tissue factor/active coagulation factor VII (TF/FVIIa) and epidermal growth factor receptor (EGFR) pathways in human colon cancer cells in culture.

METHODS

FVIIa was treated to HT-29 (KRAS-wild type) and LoVo (KRAS-mutant) colon cancer cells to activate TF/FVIIa pathway, qRT-PCR and Western blot were used to detect the expressions of amphiregulin (AREG) and epiregulin (EREG), ligands of EGFR on mRNA and protein levels, respectively. After knocking down expression of TF by TF-targeted siRNA transfection, FVIIa was treated and mRNA expressions of AREG and EREG were detected to see whether the FVIIa-induced effects were dependent on TF. Expressions of mRNA of TF and FVII were detected by qRT-PCR following the activation of EGFR pathway by treatment with epidermal growth factor (EGF) to HT-29 and LoVo cells.

RESULTS

After TF/FVIIa pathway was activated, for HT-29 cells, expressions of AREG (on mRNA level) and EREG (both on mRNA and protein level) were significantly down-regulated versus those of control group, gene expressions of AREG and EREG were 0.55±0.09 vs.0.99 ±0.09, 0.67±0.10 vs.1.02±0.02, protein expressions of EREG were 0.54±0.09 vs.1.04±0.13, all P<0.05. For LoVo cells, expressions of AREG (both on mRNA and protein level) and EREG (on protein level) were significantly up-regulated versus those of control group, gene expression of AREG were 1.87±0.39 vs. 0.93±0.23, protein expressions of AREG and EREG were 3.09±0.73 vs.1.11±0.21, 1.53±0.19 vs.0.97±0.23, all P<0.05. The regulating effect of AREG and EREG mRNA expression by FVIIa in HT-29 and LoVo cells could both be partly blocked by knocking down TF expression. For HT-29 cells, activation of EGFR pathway induced no significant TF mRNA expression, FVII mRNA expression was not detected. However,for LoVo cells, activation of EGFR pathway induced significantly higher mRNA expressions of both TF and FVII, expressions were 1.53±0.23 vs.1.00±0.23, 53.20±6.08 vs.1.00±0.15, all P<0.05.

CONCLUSION

In colon cancer cell LoVo, when activated, TF/FVIIa pathway and EGFR pathway could interact through upregulating the other pathway's effectors, and mutant KRAS might play a critical role in the two pathways' cross talk.

Quantitative structure-activity relationship of anti-HIV integrase and reverse transcriptase inhibitors using norm indexes

The development of new and safe anti-human immunodeficiency virus (anti-HIV) drugs has been an urgent task for medical research recently. Herein, based on the norm-index descriptors proposed in this work and previous works, a couple of models were developed for investigating the quantitative structure-activity/toxicity relationship (QSAR/QSTR) of dual-target anti-HIV integrase (IN) and reverse transcriptase (RT) inhibitors. The validation results proved that the developed models were stable and reliable, both in statistical quality and predictive capacity. Moreover, potential dual-target inhibitors with high activity and low toxicity were deduced from the developed models; molecular docking results indicated that these inhibitors could interact with some important residues of HIV IN and RT through H-bonding. Accordingly, the norm indexes descriptors proposed by this work might be helpful for the research and development of dual-target anti-HIV drugs.

Calcitriol, the Active Metabolite of Vitamin D3, Inhibits Dry Eye Related Corneal Inflammation In Vivo and In Vitro

PURPOSE

To examine the influence of topical administration of calcitriol on dry eye (DE) related corneal inflammation.

METHODS

Benzalkonium chloride (BAC, 0.2%) was applied to induce DE. Then rats were treated topically with calcitriol (10^-6μM). Tear break-up time (TBUT), fluorescein staining score, inflammatory index, and tear volume were measured. Corneal epithelium damage and corneal inflammation were examined by H&E staining or RT-qPCR. In vitro, human corneal epithelial cells (iHCEC) were cultured in hyperosmotic medium (450 mOsM) with various concentrations of calcitriol. Levels of pro-inflammatory mediators were measured by RT-qPCR or ELISA. NF-κB activation was examined by Western blotting and immunofluorescence staining.

RESULTS

Calcitriol significantly ameliorated DE symptoms, attenuating corneal inflammation. In vitro studies showed that calcitriol significantly decreased the expression of pro-inflammatory mediators in iHCECs under hyperosmotic stress, probably through inhibiting NF-κB activation.

CONCLUSION

The results suggest that calcitriol might be a potential therapeutic agent for DE.

[Dabigatran versus warfarin for the prevention of stroke in Chinese patients with nonvalvular atrial fibrillation: Chinese subpopulation analysis of RE-LY]

Objective: This analysis was performed to evaluate the efficacy in stroke prevention and safety of dabigatran in Chinese nonvalvular atrial fibrillation(NVAF) patients enrolled in RE-LY trial. Methods: RE-LY was an prospective, open-label, randomized, multicenter study. From March 2006 to March 2009, 541 atrial fibrillation patients at risk of stroke were recruited from 13 medical centers in China. Patients randomly received, in a blinded fashion, fixed doses of dabigatran-110 mg or 150 mg twice daily or, in an unblinded fashion, adjusted-dose warfarin. The primary efficacy endpoint was stroke or systemic embolism. The primary safety endpoint was major bleeding. Results: The incidence of stroke in the Chinese subpopulation was 1.94% per year(7 cases) in the group that received 110 mg of dabigatran (dabigatran 110) and 1.10% per year(4 cases) in the group that received 150 mg of dabigatran (dabigatran 150), as compared with 2.87% per year (10 cases) in warfarin group . Incidence of ischemic stroke was 1.11% per year(4 patients) in dabigatran 110 group, 0.82% per year(3 cases) in dabigatran 150 group and 2.01% per year(7 patients) in warfarin group. Incidence of hemorrhagic stroke was 0.28% per year(1 case) in dabigatran 110 group, 0.27% per year(1 case) in dabigatran 150 group and 0.57% per year(2 cases) in warfarin group. All-cause mortality was similar among the three treatment groups: 3.33% per year(12 cases) in dabigatran 110, 2.19% per year(8 cases) in dabigatran 150 and 2.58% per year(9 cases) in warfarin group. Incidence of major bleeding event was 0.56% per year(2 cases) in both dabigatran groups, as compared with 1.43% per year(5 cases) in warfarin group. Gastrointestinal disorders such as dyspepsia occurred in 12.8% patients of both dabigatran groups, and in 5.6% patients of warfarin group. Conclusions: Despite the descriptive statistical analysis in nature of present study due to the limited number of subjects, our subgroup analysis implies that like warfarin, dabigatran is efficacious and safe for thromboembolism prevention in Chinese patients with atrial fibrillation at risk of stroke. Clinical Trail Registry National Institutes of Health(http: //www.clinicaltrials.gov), CT00262600.

Direct measurement of B-cell receptor repertoire's composition and variation in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that is known to be associated with polyclonal B-cell hyper-reactivity. B-cell receptor (BCR) has a central role in B-cell development, activation, survival and apoptosis, and thus is a critical component of the regulation of both protective and autoreactive B cells. In this study, we applied multiplex PCR and Illumina high-throughput sequencing to study the composition and variation of the BCRs in peripheral blood mononuclear cells from SLE patients and healthy donors (NC). We found that SLE group displayed significantly shorter CDR3 average length (14.86±0.76aa vs 15.70±0.43aa), more arginine percentage of CDR3 amino acids (7.57±0.20% vs 7.32±0.19%) and poorer immunological diversity than the healthy ones. CDR3 sequence YGMDV present in all SLE samples may provide more information in generating more effective B-cell targeted diagnosis/therapies strategies.

Bacterial communities associated with invasive populations of Bactrocera dorsalis (Diptera: Tephritidae) in China

The oriental fruit fly Bactrocera dorsalis (Hendel) is a destructive insect pest of a wide range of fruits and vegetables. This pest is an invasive species and is currently distributed in some provinces of China. To recover the symbiotic bacteria of B. dorsalis from different invasion regions in China, we researched the bacterial diversity of this fruit fly among one laboratory colony (Guangdong, China) and 15 wild populations (14 sites in China and one site in Thailand) using DNA-based approaches. The construction of 16S rRNA gene libraries allowed the identification of 24 operational taxonomic units of associated bacteria at the 3% distance level, and these were affiliated with 3 phyla, 5 families, and 13 genera. The higher bacterial diversity was recovered in wild populations compared with the laboratory colony and in samples from early term invasion regions compared with samples from late term invasion regions. Moreover, Klebsiella pneumoniae and Providencia sp. were two of the most frequently recovered bacteria, present in flies collected from three different regions in China where B. dorsalis is invasive. This study for the first time provides a systemic investigation of the symbiotic bacteria of B. dorsalis from different invasion regions in China.

Elevated serum homocysteine level as an independent risk factor for erectile dysfunction: a prospective pilot case-control study

Homocysteine is an amino acid that is produced from the metabolic demethylation of dietary methionine. It has gained arising attention for its association with increased risk of myocardial infarction, stroke and venous thromboembolism. Erectile dysfunction (ED), especially for vasculogenic ED, is a vascular disorder of cavernosal vascular bed. In this prospective pilot case-control study, we investigated plasma homocysteine levels in 32 ED patients and 20 healthy control men. Related patients characteristics including age, weight, height, marital status, smoking and drinking status, level of education were collected and analysed as well as penile colour Doppler ultrasound parameters. ED patients were further categorised into mild, moderate and severe ED based on 5-item of the International Index of Erectile Function. Higher homocysteine levels were observed in ED patients as compared with controls (p < .05). A multivariate logistic regression with likelihood ratio test revealed that homocysteine and penile peak systolic blood flow velocity (PSV) levels posed significant indicators for ED (chi-square of likelihood ratio = 20.42, df = 2, p < .005) as well as moderate and severe ED occurrence (chi-square of likelihood ratio = 28.50, df = 2, p < .005). The threshold value of homocysteine concentration to discriminate ED and control subjects was 12.65 μmol/L by performing receiver operating characteristic curve analyses. These data suggested that elevation of homocysteine levels was associated with an increased risk of ED.

A Pilot Metabolic Profiling Study of Patients With Neonatal Jaundice and Response to Phototherapy

Phototherapy has been widely used in treating neonatal jaundice, but detailed metabonomic profiles of neonatal jaundice patients and response to phototherapy have not been characterized. Our aim was to depict the serum metabolic characteristics of neonatal jaundice patients relative to controls and changes in response to phototherapy. A (1) H nuclear magnetic resonance (NMR)-based metabonomic approach was employed to study the metabolic profiling of serum from healthy infants (n = 25) and from infants with neonatal jaundice (n = 30) pre- and postphototherapy. The acquired data were processed by multivariate principal component analysis (PCA) and orthogonal partial least-squares-discriminant analysis (OPLS-DA). The PLS-DA and OPLS-DA model identified nine metabolites capable of distinguishing patients from controls. In addition, 28 metabolites such as β-glucose, α-glucose, valine, and pyruvate changed in response to phototherapy. This study offers useful information on metabolic disorders in neonatal jaundice patients and the effects of phototherapy on lipids, amino acid, and energy metabolism.

[A prospective study on the effects of levonorgestrel-releasing intrauterine system for adenomyosis with menorrhagia]

OBJECTIVE

To investigate treatment effects of levonorgestrel-releasing intrauterine system (LNG-IUS) for adenomyosis with menorrhea in a prospective study.

METHODS

From December 2006 to December 2014, patients of symptomatic adenomyosis diagnosed by transvaginal ultrasound in outpatient or inpatient clinics of Peking Union Medical College Hospital were given the treatment of LNG-IUS. Before and after placement of LNG-IUS, all the patients' parameters were recorded prospectively, including scores of menstruation blood loss, carrying status of IUS, symptoms and scores of dysmenorrhea, biochemical indicators, physical parameters, menstruation patterns and adverse effects. Changes of pictorial chart scores of menstruation and distribution of anemia during follow-up were analyzed.

RESULTS

Totally 1 100 women meets inclusion criteria, among which 618 cases (56.18%, 618/1 100) had severe menorrhea, with median follow-up period of 28 months (range 1- 60 months), and accumulative carrying rate of 66% at 60 months follow-up. After placement of LNG-IUS, compared with baselines, pictorial chart scores and ratio of menorrhea had decreased significantly (all P<0.01), the scroes of menstruation were 157±34, 94±35, 70±33, 67±18, 67±20, 65±19, 66±19, 65±21 at 0, 3, 6, 12, 24, 36, 48 and 60 months respectively. During 24 months after placement of LNG-IUS, pictorial chart scores and distribution of anemia had improved significantly compared with preceding period (all P<0.01). We found no dependent factors predicting improvement of pictorial chart scores of menorrhea, which was neither relevant with simultaneous changes of menstruation patterns nor adverse effects (all P>0.05).

CONCLUSIONS

LNG-IUS is effective for adenomyosis of menorrhea. Improvement of menstruation blood loss is independent on patients characters, menstruation patterns or adverse effects.

[A prospective cohort study on effects of levonorgestrel-releasing intrauterine system for adenomyosis with severe dysmenorrhea]

OBJECTIVE

To investigate treatment effects of levonorgestrel-releasing intrauterine system (LNG-IUS) for adenomyosis with severe dysmenorrhea in a prospective cohort study.

METHODS

From December 2006 to December 2014, patients of symptomatic adenomyosis diagnosed by transvaginal ultrasound in outpatient or inpatient clinics of Peking Union Medical College Hospital were given the treatment of LNG-IUS. Before and after placement of LNG-IUS, all the patients' parameters were recorded prospectively, including symptoms and scores of dysmenorrhea, menstruation scores, biochemical indicators, physical parameters, carrying status of LNG-IUS, menstruation patterns and adverse effects. Changes of scores and patterns of pain during follow-up were analyzed.

RESULTS

Totally 1 100 women meets inclusion criteria, among which 640 cases (58.18%, 640/1 100) had severe dysmeorrhea, with median follow-up period of 35 months (range 1-60 months), and accumulative carrying rate of 65% at 60 months follow-up. After placement of LNG-IUS, scores of pain and ratio of severe dysmenorrhea had decreased significantly compared with baselines (all P<0.01), the scroes of visual analog scale (VAS) were 8.1±0.9, 5.5±2.4, 4.6±2.4, 3.3±2.2, 2.2±2.1, 2.2±1.8, 1.4±1.6 and 1.3±1.3 at 0, 3, 6, 12, 24, 36, 48 and 60 months respectively. During 36 months after placement of LNG-IUS, scores of pain had improved significantly compared with preceding period (all P<0.01). We found no universal dependent factors predicting improvement of pain, which was neither relevant with simultaneous changes of menstruation patterns nor adverse effects (all P>0.05).

CONCLUSION

LNG-IUS is effective for adenomyosis of severe dysmenorrhea. Improvement of pain is independent on patients characters, menstruation patterns or adverse effects.

Evaluation of tumour vascular distribution and function using immunohistochemistry and BOLD fMRI with carbogen inhalation

AIM

To evaluate oxygenation changes in rat subcutaneous C6 gliomas using blood-oxygen-level dependent (BOLD) functional magnetic resonance imaging (fMRI) combined with non-haemodynamic response function (non-HRF) analysis.

MATERIALS AND METHODS

BOLD fMRI were performed during carbogen inhalation in 20 Wistar rats bearing gliomas. Statistical maps of spatial oxygenation changes were computed by a dedicated non-HRF analysis algorithm. Three types of regions of interest (ROIs) were defined: (1) maximum re-oxygenation zone (ROI_max), (2) re-oxygenation zones that were less than the maximum re-oxygenation (ROI_non-max), and (3) zones without significant re-oxygenation (ROI_none). The values of percent BOLD signal change (PSC), percent enhancement (ΔSI), and significant re-oxygenation (T) were extracted from each ROI. Tumours were sectioned for histology using the fMRI scan orientation and were stained with haematoxylin and eosin and CD105. The number of microvessels (MVN) in each ROI was counted. Differences and correlations among the values for T, PSC, ΔSI, and MVN were determined.

RESULTS

After carbogen inhalation, the PSC significantly increased in the ROI_max areas (p<0.01) located in the tumour parenchyma. No changes occurred in any of the ROI_none areas (20/20). Some changes occurred in a minority of the ROI_non-max areas (3/60) corresponding to tumour necrosis. MVN and PSC (R=0.59, p=0.01) were significantly correlated in the ROI_max areas. In the ROI_non-max areas, MVN was significantly correlated with PSC (R=0.55, p=0.00) and ΔSI (R=0.37, p=0.00).

CONCLUSIONS

Statistical maps obtained via BOLD fMRI with non-HRF analysis can assess the re-oxygenation of gliomas.

Cyanophenyl vs. pyridine substituent: impact on the adlayer structure and formation on HOPG and Au(111)

A new cyano substituted bis(terpyridine) derivative CN-BTP was synthesized and its adsorption on highly oriented pyrolytic graphite (HOPG) and Au(111) was investigated. CN-BTP is closely related to the previously investigated 2,4'-BTP, where the cyanophenyl groups are replaced by pyridine moieties. The scanning tunneling microscopy (STM) investigation of CN-BTP at the liquid|HOPG interface shows a highly ordered herringbone structure that is stabilized by double weak intermolecular C-HN hydrogen bonds, partially through the -CN substituents, which is different from the most stable square structure of 2,4'-BTP. The adsorption processes were investigated using cyclic voltammetry (CV) on Au(111) in a neutral phosphate buffer. A fast and full adlayer formation could be observed with CN-BTP, whereas an extremely slow process with 2,4'-BTP under the same conditions was found. Our data show that the CN substituents on BTP not only change the structure of the monolayer at the liquid|HOPG interface, but also accelerate the phase transition process in the electrolyte dramatically. This could be explained by the adlayer-substrate interactions, which is supported by DFT calculations. Our findings might be extended more generally to further pyridine comprising self-assembling molecules to fine-tune the adlayer structure and phase transition/adsorption kinetics by replacing pyridine by cyanophenyl moieties.

Fe-assisted Ru clusters supported on porous and graphitic carbon for ammonia decomposition to COx free hydrogen

The Fe-assisted Ru clusters catalysts showed significantly improved performance for NH₃ decomposition compared to that of Fe–C and Ru/C^# catalysts.