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.

The Grooved Rodent Incisor Recapitulates Rudimentary Teeth Characteristics of Ancestral Mammals

It is known from the paleontology studies of eutherian mammals that incisor numbers were reduced during evolution. The evolutionary lost incisors may remain as vestigial structures at embryonic stages. The recapitulation of the incisor patterns among mammalian species will potentially uncover the mechanisms underlying the phenotypic transition of incisors during evolution. Here, we showed that a minute tooth formed in the presumptive groove region of the gerbil upper incisor at the early developmental stages, during which multiple epithelial swellings and Shh transcription domains spatiotemporally appeared in the dental epithelium, suggests the existence of vestigial dental primordia. Interestingly, when we trimmed the surrounding mesenchyme from incisor tooth germs at or before the bud stage prior to ex vivo culture, the explants developed different incisor phenotypes ranging from triplicated incisors, duplicated incisors, to Lagomorpha-like incisors, corresponding to the incisor patterns in the eutherian mammals. These results imply that the phenotypic transition of incisors during evolution, as well as the achievement of ultimate incisors in adults, arose from differential integrations of primordia. However, when the incisor tooth germ was trimmed at the cap stage, a grooved incisor developed similar to the normal condition. Furthermore, the incisor tooth germ developed a small but smooth incisor after the additional removal of the minute tooth and a lateral rudiment. These results suggest that multiple dental primordia integrated before the cap stage, with the labial primordia contributing to the labial face of the functional incisor. The minute tooth that occupied the boundary of the 2 labial primordia might be implicated in the groove formation. This study sheds light on how rudiments incorporate into functional organs and aids the understanding of incisor evolution.

[Methylation status of RASSF1A gene promoter in upper tract urothelial carcinoma and its clinical significance]

OBJECTIVE

To investigate the methylation status of the RASSF1A gene promoter in upper tract urothelial carcinoma (UTUC) tissues and its correlation with clinicopathologic characteristics and postoperative recurrence of primary UTUC.

METHODS

In a retrospective design, a total of 687 patients who underwent surgeries for primary UTUC in the urology department of Peking University First Hospital were enrolled. The methylation status of the RASSF1A gene promoter was analyzed using methylation-sensitive polymerase chain reaction on tumor specimens.

RESULTS

Aberrant methylation for the RASSF1A gene promoter was detected in 183 (26.6%) DNA samples in total. Aberrant methylation of the RASSF1A gene was strongly associated with tobacco consumption (P=0.044), ipsilateral hydronephrosis (P<0.001 ), tumor location (P<0.001 ), tumor stage (P=0.001), tumor grade (P=0.007), lymph node metastasis (P=0.001) and growth pattern (P=0.013). The methylated RASSF1A gene promoter was an independent risk factor for bladder recurrence (P<0.001, HR=0.471) and contralateral recurrence (P=0.030, HR=0.269) of UTUC after surgery. Hypermethylated RASSF1A was predictive for improved bladder recurrence-free survival (BRFS) (P<0.001) and contralateral recurrence-free survival (CRFS) (P=0.021) in the UTUC patients. Compared with the patients with unmethylated RASSF1A, the patients containing tumors with hypermethylated RASSF1A had tendency toward longer recurrence-free survival time [(114.4±3.9) months vs. (84.0±3.2) months for BRFS, (138.1±1.8) months vs. (132.9±1.9) months for CRFS] and higher estimated cumulative recurrence-free survive rates ( five-year survival rate for example, 79.8%±3.4% vs. 57.4%±2.6% for BRFS, 98.9%±0.8% vs. 93.0%±1.4% for CRFS). Additionally, tumor multifocality (P=0.002, HR=1.538), and ureteroscopy before surgery (P=0.001, HR=1.725) were independent risk factors for bladder recurrence in postoperative UTUC patients.

CONCLUSION

The methylation status of the RASSF1A gene promoter appears to be a promising epigenomic biomarker for assessing the aggressiveness of UTUC and a predictor predicting the urinary tract recurrence after surgery.

Highly efficient electro-generation of hydrogen peroxide using NCNT/NF/CNT air diffusion electrode for electro-Fenton degradation of p-nitrophenol

To promote the in situ generation of hydrogen peroxide (H2O2) in electro-Fenton system, a new air diffusion electrode (ADE) was put forward in the present work using N-doped multi-walled carbon nanotubes (NCNT) as the catalyst layer, multi-walled carbon nanotubes (CNT) as the diffusion layer, and nickel foam (NF) as the supporting material, respectively. The catalyst layer in ADE was characterized by transmission electron microscopy and X-ray photoelectron spectroscopy. Then the performances of H2O2 accumulation and p-nitrophenol (p-NP) degradation with the electrode (NCNT/NF/CNT ADE) were investigated. The experimental results showed that H2O2 accumulation on the NCNT/NF/CNT ADE was greatly improved by the presence of N doping, and H2O2 accumulation concentration could reach 307 mg L(-1) after 120 min at the current intensity of 100 mA. Moreover, the NCNT/NF/CNT ADE presented more effective performance on p-NP degradation than the CNT/NF/CNT ADE or the NF ADE. p-NP of initial 50 mg L(-1) could be almost completely removed after 30 min, and the total organic carbon removal efficiency reached 62.61% after 120 min when 0.4 mM Fe(2+) was added into the system. The repeatability test suggested that the stability of the NCNT/NF/CNT ADE was very good.

miR-96 inhibits cardiac hypertrophy by targeting growth factor receptor-bound 2

Increasing evidence has indicated that microRNAs are involved in the pathogenesis of cardiac hypertrophy. However, whether miR-96 is involved in heart diseases, particularly cardiac hypertrophy, remains unclear. In this study, we found that miR-96 is a negative regulator of cardiac hypertrophy. In primary cardiomyocytes, overexpression of miR-96 inhibited phenylephrine-induced cardiomyocyte hypertrophy and decreased the mRNA expression of cardiac hypertrophy markers such as atrial natriuretic factor and β-myosin heavy chain. Interestingly, we found that growth factor receptor-bound 2 is a direct target of miR-96, which is a negative regulator of cardiac hypertrophy. Overexpression of miR-96 in cardiomyocytes led to reduced growth factor receptor-bound 2 expression. More importantly, miR-96 repressed the extracellular-regulated protein kinase signaling pathway by targeting growth factor receptor-bound 2 in cardiomyocytes. Our data demonstrate that miR-96 is a negative regulator of cardiac hypertrophy and extracellular-regulated protein kinase signaling, thus offering a new therapeutic strategy for cardiac hypertrophy.

Protein-protein interaction network and mechanism analysis of hepatitis C

We predicted potential genes and identified pathways associated with hepatitis C. The gene expression profiles of GSE40184 from blood samples and GSE38597 from liver biopsy samples were downloaded from the GEO database. Differentially expressed genes (DEGs) were recognized using the Limma Package. The Pearson correlation test was used to construct the co-expression network of DEGs. Gene set enrichment analysis was used to define significant functions and pathways for DEGs. A total of 165 DEGs in blood samples and 523 DEGs in liver biopsy samples were identified. Eight DEGs were common between these samples. Gene Ontology enrichment analysis showed that 165 DEGs in blood samples were significantly enriched regarding the response to protein binding, receptor binding, G-protein coupled receptor binding, cytokine receptor binding, and cytokine activity. The most significant term of the Kyoto Encyclopedia of Genes and Genomes pathway was the cytokine-cytokine receptor interaction. Protein-protein interaction network analysis indicated that three subnetworks with more nodes and edges were involved in these interactions. We used robust biomarkers that were differentially expressed in hepatitis C and determined their relevance in the biological function, signal pathways, protein-protein interaction network, and co-expression network of hepatitis C.

Mycophenolic acid upregulates miR-142-3P/5P and miR-146a in lupus CD4+T cells

BACKGROUND

Mycophenolic acid (MPA), the active metabolite of mycophenolate mofetil (MMF), is a noncompetitive inhibitor of inosine monophosphate dehydrogenase, and is now widely used for the treatment of systemic lupus erythematosus (SLE). Dysregulated expression of microRNA has been reported to be associated with the pathogenesis of SLE. However, it is unexplored whether altering microRNA expression in SLE patients is one of the therapeutic effects of MPA.

OBJECTIVES

This study thus aims to investigate the effect of MPA on microRNAs expression in lupus CD4(+)T cells and its underlying mechanisms.

RESULTS

According to our microarray data, 101 upregulated microRNAs and 77 downregulated microRNAs were identified in MPA-treated lupus CD4(+)T cells. Among these microRNAs, miR-142-3p/5p and miR-146a expression was found to be significantly increased in MPA-treated lupus CD4(+)T cells compared to untreated controls. Furthermore, we observed that MPA-treated CD4(+)T cells from patients with SLE showed enriched levels of H4 acetylation in the putative miRNA-142 regulatory region and enhanced levels of H3 acetylation in the putative miRNA-146a regulatory region compared to untreated cells.

CONCLUSION

Data from this study suggest that MPA activates miR-142 and miR-146a expression through histone modification at the promoter region, which may partially explain the pharmacological mechanisms of MPA for SLE.

Gene expression profile of IGF1 and MSTN mRNA and their correlation with carcass traits in different breeds of geese at 70 d of age

1. The expression of insulin-like growth factor-1 (IGF1) and myostatin (MSTN) mRNA in breast and leg muscle was quantified in 70-d-old Taihu and Wanxi geese by using a Multiplex Competitive Fluorescent-PCR method and the correlations between mRNA levels and carcass traits were analysed. 2. IGF1 mRNA expression in breast muscle in Taihu geese was significantly higher than that in Wanxi geese and the MSTN mRNA level in leg muscle in Taihu geese was significantly higher than that in Wanxi geese. 3. There was no significant difference in breast muscle MSTN or leg muscle IGF1 mRNA expression between the two breeds. 4. Within the same breed, the IGF1 mRNA expression in leg muscle of male geese was significantly higher than that in female geese, and MSTN mRNA expression in leg muscle was significantly higher than that in breast muscle. 5. There was no difference in the IGF1 mRNA expression between tissues. 6. There was a positive correlation between IGF1 mRNA and MSTN mRNA and a negative correlation between IGF1 mRNA expression of breast muscle and leg muscle ratio. 7. In Wanxi geese, MSTN mRNA expression in leg muscle was negatively associated with body weight and leg muscle weight.

Analysis of age of onset, pre-existing infections, and features of magnetic resonance imaging results in patients with acute myelitis

The clinical features and potential risk factors of acute myelitis (AM) were investigated. The medical records of patients with AM admitted to our department between January 2004 and December 2011 were collected and retrospectively analyzed. The diagnosis of AM was in line with the diagnostic criteria of the Transverse Myelitus Consortium Working Group. The age of onset, clinical, and imaging features of these patients were analyzed. A total of 64 patients satisfying the inclusion criteria were enrolled in the study, including 39 males and 25 females. The patients ranged in age from 1 to 80 years, with a mean age of 34 years. Twenty-three patients had symptoms of pre-existing infections. The correlation between spinal cord lesions and spinal lesions was statistically significant (P<0.05). Cervical spinal cord inflammation was the most common. Prodromal infections were more commonly observed in thoracic spinal cord myelitis than in cervical spinal cord myelitis (P<0.05). AM appears to be more likely to occur in male minors. Lesions of the spinal column were partially implicated with the occurrence of myelitis, which suggests that such lesions might be a predisposing factor. Compared to AM of the cervical cord, pre-existing infections appear to be of greater significance for the occurrence of myelitis of the thoracic cord.

Evaluation of bamboo genetic diversity using morphological and SRAP analyses

Bamboo is an important member of the giant grass subfamily Bambusoideae of Poaceae. In this study, 13 bamboo accessions belonging to 5 different genera were subjected to morphological evaluation and sequence-related amplified polymorphism (SRAP) analysis. Unweighted pair-group method of arithmetic averages (UPGMA) cluster analysis was used to construct a dendrogram and to estimate the genetic distances among accessions. On the basis of morphological characteristics, the 13 accessions were distinctly classified into 2 major clusters; 3 varieties, PPYX, PGNK, and PLYY were grouped as cluster A, and 10 accessions were categorized under cluster B. Similarity coefficients ranging from 0.23 to 0.96 indicated abundant genetic variation among bamboo varieties. Approximately 38 SRAP primer combinations generated 186 bands, with 150 bands (80.65%) showing polymorphisms among the 13 accessions. Based on SRAP analysis, 13 bamboo accessions were grouped into 3 major clusters. Five species comprised Cluster I (PASL, PLYY, PTSC, SCNK, and BMAK), which belongs to genus Phyllostachys. Cluster II consisted of 5 varieties, PASL, PLYY, PTSC, SCNK, and BMAK; Cluster III included 3 varieties, PGNK, PLSY, and BMRS. Comparison of the results generated by morphological and SRAP analyses showed that the classification based on SRAP markers was more concordant to the taxonomic results of Gamble than that performed using morphological characters, thus suggesting that SRAP analysis is more efficient in evaluating genetic diversity in bamboos compared to morphological analysis. The SRAP technique serves as an alternative method in assessing genetic diversity within bamboo collections.

Metformin promotes autophagy and apoptosis in esophageal squamous cell carcinoma by downregulating Stat3 signaling

The antidiabetic drug metformin exerts chemopreventive and antineoplastic effects in many types of malignancies. However, the mechanisms responsible for metformin actions appear diverse and may differ in different types of cancer. Understanding the molecular and cellular mechanisms specific for different cancers is important to optimize strategy for metformin treatment in different cancer types. Here, we investigate the in vitro and in vivo effects of metformin on esophageal squamous cell carcinoma (ESCC) cells. Metformin selectively inhibited cell growth in ESCC tumor cells but not immortalized noncancerous esophageal epithelial cells. In addition to apoptosis, metformin triggered autophagy. Pharmacological or genetic inhibition of autophagy sensitized ESCC cells to metformin-induced apoptotic cell death. Mechanistically, signal transducer and activator of transcription 3 (Stat3) and its downstream target Bcl-2 was inactivated by metformin treatment. Accordingly, small interfering RNA (siRNA)-mediated Stat3 knockdown enhanced metformin-induced autophagy and apoptosis, and concomitantly enhanced the inhibitory effect of metformin on cell viability. Similarly, the Bcl-2 proto-oncogene, an inhibitor of both apoptosis and autophagy, was repressed by metformin. Ectopic expression of Bcl-2 protected cells from metformin-mediated autophagy and apoptosis. In vivo, metformin downregulated Stat3 activity and Bcl-2 expression, induced apoptosis and autophagy, and inhibited tumor growth. Together, inactivation of Stat3-Bcl-2 pathway contributes to metformin-induced growth inhibition of ESCC by facilitating crosstalk between apoptosis and autophagy.

Effect of the IkBα mutant gene delivery to mesenchymal stem cells on rat chronic pancreatitis

This study aimed to investigate the effect of inhibitors of the NF-kΒ alpha mutant gene (IkBaM) delivery to mensenchymal stem cells (MSCs) on rat chronic pancreatitis (CP). A total of 120 Sprague-Dawley rats were randomly divided into 6 groups of 20: Group A was injected with sterile saline solution, Group B was injected with allogenic MSCs, Group C1 was injected with allogenic IkBαM-MSCs cultured in vitro 4 h before CP modeling, Group C2 was injected with allogenic IkBαM-MSCs cultured in vitro during CP modeling, Group C3 was cultured with allogenic IkBαM-MSCs cultured in vitro 4 h after CP modeling, and Group D was injected with rAAV2-MSCs. Cytokine levels of ICAM-1, CTGF, IL-1, IL-6, IL-8, TNF-α, TIMP-1, TIMP-2, IL-10, FN, MMP-1, MMP-2, MMP-3, and MMP-9 were examined. The results indicated that allogenic IκBαM-MSCs could reduce pro-inflammatory cytokine levels and increase anti-inflammatory cytokine levels in CP. The allogenic IkBαM-MSCs reduced the activation and promoted the apoptosis of pancreatic stellate cells in the rat model of CP. IkBαM-MSCs influenced the proliferation and apoptosis of pancreatic stellate cells by regulating the activation of the PPAR, MAPK, mTOR, TGF-β, NOD-like receptor, Notch, WNT, TGF-β1-SMAD-2/3, and P53 signal transduction pathways.

Attenuation of donor-reactive T cells allows effective control of allograft rejection using regulatory T cell therapy

Regulatory T cells (Tregs) are essential for the establishment and maintenance of immune tolerance, suggesting a potential therapeutic role for Tregs in transplantation. However, Treg administration alone is insufficient in inducing long-term allograft survival in normal hosts, likely due to the high frequency of alloreactive T cells. We hypothesized that a targeted reduction of alloreactive T effector cells would allow a therapeutic window for Treg efficacy. Here we show that preconditioning recipient mice with donor-specific transfusion followed by cyclophosphamide treatment deleted 70-80% donor-reactive T cells, but failed to prolong islet allograft survival. However, infusion of either 5 × 10(6) Tregs with direct donor reactivity or 25 × 10(6) polyclonal Tregs led to indefinite survival of BALB/c islets in more than 70% of preconditioned C57BL/6 recipients. Notably, protection of C3H islets in autoimmune nonobese diabetic mice required islet autoantigen-specific Tregs together with polyclonal Tregs. Treg therapy led to significant reduction of CD8(+) T cells and concomitant increase in endogenous Tregs among graft-infiltrating cells early after transplantation. Together, these results demonstrate that reduction of the donor-reactive T cells will be an important component of Treg-based therapies in transplantation.

Pretreatment of furfural industrial wastewater by Fenton, electro-Fenton and Fe(II)-activated peroxydisulfate processes: a comparative study

The Fenton, electro-Fenton and Fe(II)-activated peroxydisulfate (PDS) processes have been applied for the treatment of actual furfural industrial wastewater in this paper. Through the comparative study of the three processes, a suitable pretreatment technology for actual furfural wastewater treatment was obtained, and the mechanism and dynamics process of this technology is discussed. The experimental results show that Fenton technology has a good and stable effect without adjusting pH of furfural wastewater. At optimal conditions, which were 40 mmol/L H₂O₂ initial concentration and 10 mmol/L Fe²⁺ initial concentration, the chemical oxygen demand (COD) removal rate can reach 81.2% after 90 min reaction at 80 °C temperature. The PDS process also has a good performance. The COD removal rate could attain 80.3% when Na₂S₂O₈ initial concentration was 4.2 mmol/L, Fe²⁺ initial concentration was 0.1 mol/L, the temperature remained at 70 °C, and pH value remained at 2.0. The electro-Fenton process was not competent to deal with the high-temperature furfural industrial wastewater and only 10.2% COD was degraded at 80 °C temperature in the optimal conditions (2.25 mA/cm² current density, 4 mg/L Na₂SO₄, 0.3 m³/h aeration rate). For the Fenton, electro-Fenton and PDS processes in pretreatment of furfural wastewater, their kinetic processes follow the pseudo first order kinetics law. The pretreatment pathways of furfural wastewater degradation are also investigated in this study. The results show that furfural and furan formic acid in furfural wastewater were preferentially degraded by Fenton technology. Furfural can be degraded into low-toxicity or nontoxic compounds by Fenton pretreatment technology, which could make furfural wastewater harmless and even reusable.

Clinical grade manufacturing of human alloantigen-reactive regulatory T cells for use in transplantation

Regulatory T cell (Treg) therapy has the potential to induce transplantation tolerance so that immunosuppression and associated morbidity can be minimized. Alloantigen-reactive Tregs (arTregs) are more effective at preventing graft rejection than polyclonally expanded Tregs (PolyTregs) in murine models. We have developed a manufacturing process to expand human arTregs in short-term cultures using good manufacturing practice-compliant reagents. This process uses CD40L-activated allogeneic B cells to selectively expand arTregs followed by polyclonal restimulation to increase yield. Tregs expanded 100- to 1600-fold were highly alloantigen reactive and expressed the phenotype of stable Tregs. The alloantigen-expanded Tregs had a diverse TCR repertoire. They were more potent than PolyTregs in vitro and more effective at controlling allograft injuries in vivo in a humanized mouse model.