[Experimental studies on correlation between nucleolus spindle-related protein 1 and the malignant progression and prognosis of human glioblastoma multiforme]

Objective: To investigate the correlation between nucleolus spindle-related protein 1 (NUSAP1) and malignant progression and prognosis of human glioblastoma multiforme (GBM). Methods: RT-PCR and immunohistochemical technique were applied to analyze NUSAP1 expression level in GBM surgical specimens. Correlations between NUSAP1 expression and molecular classification and survival of patients with GBM were also investigated in TCGA database. The gene silencing technique was used to silence NUSAP1 expression in U87 cells, CCK-8 assay was used to detect cell proliferation, flow cytometry was used to detect cell cycle changes, and in vivo tumorigenicity was evaluated after NUSAP1 silencing in tumor-bearing mice. Results: NUSAP1 expression level in GBM was higher than that in non-tumor brain tissue. Survival curve analysis showed that the survival time of GBM patients with high NUSAP1 expression decreased significantly (P<0.01). NUSAP1 expression was relatively lower in mesenchymal and neural molecular subtypes of GBM, when compared with the other two molecular subtypes. And it was closely related with specific genetic aberrations (such as PTEN loss and IDH1 mutation). Silencing NUSAP1 inhibited G2/M cell cycle progression of GBM cells, and inhibited cell proliferation both in vitro and in vivo. Conclusion: Expression of NUSAP1 is closely related to progress and prognosis of GBM, and can be a biomarker reflecting GBM prognosis and act as a therapeutic target with potential clinical application value.

Thiazolidinediones versus metformin on improving abnormal liver enzymes in patients with type 2 diabetes mellitus: a meta-analysis

Background

Liver enzyme abnormalities are common in patients with type 2 diabetes. Currently, the inverse relationship between elevated liver enzymes and antidiabetics intake may be explained by rigorous treatment and good control. However, few studies have directly explored the influence of antidiabetics on abnormal liver function, especially the comparison between two insulin sensitizers—thiazolidinediones and metformin.

Materials And Methods

Databases, including PubMed, Cochrane, CNKI, Wanfang and VIP were searched. Two reviewers performed independently. Meta-analysis was used when studies were homogeneous enough.

Results

Six studies, including 4726 patients with type 2 diabetes, were involved in this systematic review. Compared with metformin, thiazolidinediones significantly reduced the alanine transaminase, aspartate aminotransferase and gamma-glutamyl transpeptidase. Further subgroup analysis suggested that pioglitazone-treated participants showed vast improvement in decreasing alanine transaminase (MD = -13.70; 95% CI = -16.91 to -10.52; P < 0.00001; I² = 1%), aspartate aminotransferase (MD = -3.51; 95% CI = -5.74 to –1.28; P = 0.002; I² = 0%) and gamma-glutamyl transpeptidase (MD = -5.41; 95% CI = -9.40 to -1.42; P = 0.008; I² = 0%), while rosiglitazone exhibited no difference in lowering corresponding liver enzyme levels. Besides, thiazolidinediones similarly decreased fasting plasma glucose. However, thiazolidinediones were inferior to metformin in lowering HbA1C and alkaline phosphatase. Additionally, no significant publication bias was seen.

Conclusions

Thiazolidinediones may confer modest biological improvement of liver function in people with type 2 diabetes than metformin. But owing to the limited methodological quality, more clinical researches are warranted in the future.

[Experimental study of glioma stem cell-mediated immune tolerance in tumor microenvironment]

Objective: To investigate the tumor microenvironment of immune tolerance induced by glioma stem cells (GSC). Methods: Human GSC SU3 cells transfected with red fluorescent protein (SU3-RFP) gene were implanted into the brain, subcutis (armpit and foot), liver and abdominal cavity of transgenic green fluorescence protein (GFP) nude mice to establish RFP(+) /GFP(+) dual fluorescence solid tumor model. The re-cultured cells derived from implanted tumor tissues, SU3-RFP cells co-cultured with peritoneal fluid of transgenic GFP nude mice and malignant ascites of tumor-bearing mice were observed by fluorescence microscopy and real-time video image tracing to analyze the microenvironment of immune tolerance mediated by RFP(+) /GFP(+) implanted tumor. Results: Dual fluorescence labeled frozen section showed that all of cells in the tumor microenvironment were GFP(+) , while the pressed tissue-patch showed that the tumor blood vessels exhibited a RFP(+) /GFP(+) double-positioning yellow. In the GFP single fluorescence labeled tumor tissue, all of cells in the microenvironment were green, including tumor edge, necrotic foci and blood vessel. Among them, CD68(+) , F4/80(+) , CD11c(+) , CD11b(+) and CD80(+) cells were observed. In the dual fluorescence labeled co-cultured cells, the phagocytosis and fusion between green host cells and red tumor cells were also observed, and these fusion cells might transfer to the malignant dendritic cells and macrophages. Conclusions: The tumor microenvironment of immune tolerance induced by GSC is not affected by the tissue types of tumor-inoculated sites, and the immune tolerance mediated by inflammatory cells is associated with the inducible malignant transformation, which may be driven by cell fusion.

Immunotolerant indoleamine-2,3-dioxygenase is increased in condyloma acuminata

BACKGROUND

The tryptophan-depleting enzyme indoleamine-2,3-dioxygenase (IDO) is critical for the regulation of immunotolerance and plays an important role in immune-associated skin diseases.

OBJECTIVES

To analyse the level of IDO in condyloma acuminata (CA) and its role in this condition.

METHODS

IDO expression was assessed in the skin and peripheral blood of healthy controls and patients with CA. To assess the role of skin IDO in immunity, the ability of isolated epidermal cells to metabolize tryptophan and the influence on polyclonal T-cell mitogen (PHA)-stimulated T-cell proliferation were explored.

RESULTS

IDO median fluorescence intensities in peripheral blood mononuclear cells from patients with CA were similar to those from healthy controls. Immunohistochemistry showed that IDO⁺ cells were rare in normal skin and the control skin of patients with CA, but were greatly accumulated in wart tissue. Most fluorescence signals of IDO⁺ cells did not overlap with those of CD1a⁺ Langerhans cells. Human papillomavirus (HPV) DNA probe in situ hybridization showed a large number of IDO⁺ cells in the HPV^- site. Keratinocytes in the skin of healthy controls and the circumcised skin of patients with CA could minimally transform tryptophan into kynurenine, but IDO-competent epidermal cells from warts could transform tryptophan. In addition, these IDO-competent epidermal cells could inhibit PHA-stimulated T-cell proliferation. The addition of an IDO inhibitor, 1-methyl-d-tryptophan, restored the inhibited T-cell proliferation.

CONCLUSIONS

Abnormally localized high IDO expression might be involved in the formation of a local immunotolerant microenvironment.

MicroRNA-155 is a biomarker of T-cell activation and immune dysfunction in HIV-1-infected patients

OBJECTIVES

MicroRNA-155 (miR-155) regulates T-cell differentiation and activation. It has also been associated with HIV infection. However, it remains unclear whether miR-155 is related to the T-cell response in HIV-infected individuals (e.g. T-cell activation and exhaustion).

METHODS

We performed a cross-sectional study involving 121 HIV-1-infected patients on highly active antiretroviral therapy (HAART) and 43 HAART-naïve patients. MiR-155 levels in the peripheral blood were determined by quantitative reverse transcription-polymerase chain reaction (PCR). T-cell immune activation, exhaustion, and homeostasis were measured by determining the expression of CD38, programmed death 1 (PD-1) and CD127 via flow cytometry.

RESULTS

The levels of miR-155 in total peripheral blood mononuclear cells, CD4 T cells and CD8 T cells from HIV-1-infected patients were increased (P < 0.01). Nonresponders and HAART-naïve patients also exhibited a higher percentage of CD8⁺ CD38⁺ T cells and a lower percentage of CD4⁺ CD127⁺ and CD8⁺ CD127⁺ T cells (P < 0.05). We also found higher levels of PD-1 expression on the CD4⁺ and CD8⁺ T cells of HIV-1-infected patients (P < 0.05).

CONCLUSIONS

Our findings suggest that miR-155 levels in the peripheral blood of HIV-1-infected patients are increased and associated with T-cell activation. Therefore, miR-155 is a potential biomarker of the immune response following HIV-1 infection.

[Effects of prenatal maternal seizure on hippocampal damage and cognitive deficits in offspring rats]

Objective: To observe hippocampal damage and cognitive impairment of offspring exposed to prenatal maternal seizure induced by amygdala kindling, and to explore the underlying mechanism by the detection of pathological changes of placenta. Method: Adult female SD rats were randomly divided into three groups: control group(8 rats), kindling group(12 rats) and sham group(8 rats). All the rats were allowed to mate after one week's fully kindling. The pregnant rats in kindling group received electric stimulation every 48 h. Dams were allowed to deliver naturally. Effects of maternal seizure on the number of offspring, the survival rate and body weight of pups were observed. HE staining was used to visualize histopathological changes of placenta. Morris water maze test was used to assess the cognitive function and Nissal's staining to detect hippocampal morphology of the offspring. One-way ANOVA analysis and χ² test were used. Result: Compared with the sham group (95%(78/82)) and the control group (95%(82/86)), the survival rate of pups in kindling group(81%(66/82))was much lower (χ²=13.817, P=0.001). There were no significant differences in the number of pups per litter and pups birth-weight between kindling group and sham group or control group(F=0.312 and 0.257, P=0.736 and 0.776). HE staining showed that placental tissues from control and sham groups were normal whereas the histologic abnormalities of placentas from kindling group were characterized by thickening of the villus vascular walls, luminal stenosis, trophoblasts hyperplasia, abnormalities of trophoblasts with nuclear pyknosis and karyorrhexis and accumulation of inflammatory lymphocytes in labyrinthine zone. Nissl staining showed that neurons in hippocampus of P₀(0 d after birth) and P₈₄(84 d after birth) offspring from control and sham groups were normal, but neuronal damages were obvious in hippocampus of P₀ and P₈₄ offspring from kindling groups, and the damages in P₀ pups were severe with a marked loss of neuron, shrinkage of cells and nuclear pyknosis and karyorrhexis. In the Morris water maze, compared with the sham group ((29±8), (19±9), (10±4)s) and the control group ((25±6), (17±5), (14±4)s) rats in the kindling group ((36±8), (29±8), (30±11)s) exhibited significantly longer escape latency from the 3^rd, 4^th, and 5^th days (F=6.276, 7.518, 18.422, P=0.030, 0.003, 0.000), significant less time in the target quadrant ((27±8) vs.(58±11)and(68±13)s, F=35.993, P=0.000) and reduced number of crossing the platform ((4.4±1.7) vs. (7.2±1.6) and (8.5±1.3)times, F=18.377, P=0.000). In addition, there was no significant difference between control and sham groups(P all >0.05). Conclusion: The prenatal maternal seizures induced significant pathological damages to hippocampus and cognitive impairment of offspring. Hypoxia-ischemia of placenta might play an important role in this process.

[Discussion on the species and naming of medical bamboo slips unearthed from Han tomb in Laoguanshan]

920 pieces of bamboo slip, including broken bamboo slips, found in Laoguanshan Han tomb, are placed in two locations. In one of the location, 736 pieces, except 20 pieces of " chi jian" , of medical bamboo slips are stored. The Chengdu Municipal Institute of Archaeology and Cultural Relics Protection Center of Jingzhou preliminary sorted out these pieces and tentatively give them the names: Wu se mai zang lun, Bi xi yi lun, Mai si hou, Liu shi bing fang, Bing yuan lun, Zhu bing zheng hou, Jing mai shu, Gui mai shu. Through our comprehensive reading, font comparison, comparison of the contents, and investigation on the texts, it was suggested that the batch of medical slips might be divided into nine kinds of documents, namely, Bi xi zhen fa, Zhen zhi lun, Liu shi bing fang, Zhu bing yi, Zhu bing er, Shi er mai, Bie mai, Ci shu, Ni shun wu se mai zang yan jing shen.

Rho-kinase inhibitor fasudil reduces allergic airway inflammation and mucus hypersecretion by regulating STAT6 and NFκB

BACKGROUND

Airway mucus hypersecretion is a key pathophysiological feature in asthma. Fasudil, a selective Rho-A/Rho kinase inhibitor, has been used in clinical trials to treat pulmonary hypertension. However, its function in modulating airway mucus hypersecretion in asthma remains undefined.

OBJECTIVE

We examined whether fasudil, a selective Rho-A/Rho kinase inhibitor, affects the mucus hypersecretion by suppressing MUC5AC via signal transducer and activator of transcription factor 6 (STAT6) and nuclear factor-kappa B (NFκB) in mice and cells.

METHODS

We measured mucus secretion and the expression of Rho-kinase in the airway tissue of patients with asthma. BALB/c mice were sensitized and challenged with ovalbumin (OVA) followed with fasudil treatment. The lung tissues were assessed for airway inflammation and mucus secretion. Cytokine levels and airway responsiveness were determined. STAT6 and NFκB were quantified by Western blot. 16HBE cells were stimulated with house dust mite (HDM) extracts. MUC5AC and muc5ac promoter activities were measured. Using siRNA to knockdown STAT6 in epithelial cells, we determined the impact of STAT6 on muc5ac promoter activity. NFκB nuclear translocation was observed with immunostaining.

RESULTS

Fasudil administration significantly decreased the number of inflammatory cells, inflammation index in the lung and airway responsiveness. Fasudil also reduced mucous secretion and MUC5AC expression in OVA-challenged mice. Fasudil down-regulated the levels of IL-17, IL-4 and IL-13 in the lung tissue of OVA-challenged mice. Fasudil also decreased the expression and phosphorylation of NFκB and STAT6 as well as the nuclear translocation of NFκB. In addition, human airway epithelial cells (16HBE) were challenged with HDM extracts and then treated with fasudil. Fasudil inhibited HDM extract-induced MUC5AC expression, which is associated with a reduction in STAT6 and NFκB in epithelial cells.

CONCLUSIONS AND CLINICAL RELEVANCE

These findings indicate that the Rho-A/Rho kinase inhibitor, fasudil, plays a negative regulatory role in allergen-induced mucus secretion and MUC5AC expression by regulating STAT6 and NFκB.

Primary cilia are not calcium-responsive mechanosensors

Primary cilia are solitary, generally non-motile, hair-like protrusions that extend from the surface of cells between cell divisions. Their antenna-like structure leads naturally to the assumption that they sense the surrounding environment, the most common hypothesis being sensation of mechanical force through calcium-permeable ion channels within the cilium¹. This Ca²⁺- Responsive MechanoSensor (CaRMS) hypothesis for primary cilia has been invoked to explain a large range of biological responses, from control of left-right axis determination in embryonic development to adult progression of polycystic kidney disease and some cancers^2,3. Here, we report the complete lack of mechanically induced calcium increases in primary cilia, in tissues upon which this hypothesis has been based. First, we developed a transgenic mouse, Arl13b-mCherry-GECO1.2, expressing a ratiometric genetically encoded calcium indicator (GECI) in all primary cilia. We then measured responses to flow in primary cilia of cultured kidney epithelial cells, kidney thick ascending tubules, crown cells of the embryonic node, kinocilia of inner ear hair cells, and several cell lines. Cilia-specific Ca²⁺ influxes were not observed in physiological or even highly supraphysiological levels of fluid flow. We conclude that mechanosensation, if it originates in primary cilia, is not via calcium signaling.

Comparison of the Effect of Vessel Size Imaging and Cerebral Blood Volume Derived from Perfusion MR Imaging on Glioma Grading

BACKGROUND AND PURPOSE

Vascular proliferation is a major criterion for grading gliomas on the basis of histology. Relative cerebral blood volume can provide pathophysiologic information about glioma grading. Vessel size imaging, in some animals, can be used to estimate the microvascular caliber of a glioma, but its clinical use remains unclear. Herein, we aimed to compare the predictive power of relative cerebral blood volume and vessel size imaging in glioma grading, with grading based on histology.

MATERIALS AND METHODS

Seventy patients with glioma participated in the study; 30 patients underwent MR perfusion imaging with a spin-echo sequence and vessel size imaging with a gradient-echo and spin-echo sequence successively at 24-hour intervals before surgery. We analyzed the vessel size imaging values and relative cerebral blood volume of differently graded gliomas. The microvessel parameters were histologically evaluated and compared with those on MR imaging. The cutoff values of vessel size imaging and relative cerebral blood volume obtained from receiver operating characteristic curve analyses were used to predict glioma grading in another 40 patients.

RESULTS

Vessel size imaging values and relative cerebral blood volume were both increased in high-grade gliomas compared with low-grade gliomas (P < .01). Moreover, vessel size imaging values had higher specificity and sensitivity in differentiating high-grade from low-grade gliomas compared with relative cerebral blood volume. In addition, a significant correlation was observed between vessel size imaging values and microvessel diameters (r > 0.8, P < .05) and between relative cerebral blood volume and microvessel area (r = 0.6579, P < .05). Most important, the use of vessel size imaging cutoff values to predict glioma grading was more accurate (100%) than use of relative cerebral blood volume (85%) values.

CONCLUSIONS

Vessel size imaging can provide more accurate information on glioma grading and may serve as an effective biomarker for the prognosis of patients with gliomas.

Detection of the long noncoding RNAs nuclear-enriched autosomal transcript 1 (NEAT1) and metastasis associated lung adenocarcinoma transcript 1 in the peripheral blood of HIV-1-infected patients

OBJECTIVES

Long noncoding RNAs (lncRNAs) in HIV-1 infection have not been extensively studied. Here we detected two lncRNAs, nuclear-enriched autosomal transcript 1 (NEAT1) and metastasis associated lung adenocarcinoma transcript 1 (MALAT1), in peripheral blood mononuclear cells (PBMCs) and plasma of HIV-1-infected patients.

METHODS

Fifty-nine HIV-1-infected patients and 21 healthy controls were recruited for the study, of whom 31 patients were highly active antiretroviral therapy (HAART)-naïve and 28 patients had been receiving HAART for more than 1 year with undetectable viral loads. Total RNA was extracted from PBMCs and plasma, and levels of NEAT1 and MALAT1 were determined by quantitative real-time polymerase chain reaction.

RESULTS

We found that the levels of NEAT1 and MALAT1 in PBMCs were up-regulated in HAART-naïve patients and were reduced in patients receiving HAART. NEAT1 was down-regulated in the plasma of infected patients and expression was correlated with CD4 T-cell count.

CONCLUSIONS

Our findings suggest that NEAT1 and MALAT1 may interact with HIV-1 in vivo and that the presence of NEAT1 in plasma is a potential biomarker of HIV-1 infection.

Eukaryotic elongation factor-2 kinase (eEF2K): a potential therapeutic target in cancer

Eukaryotic elongation factor-2 kinase (eEF2K), encoded by the EEF2K gene, is well-known to be a Ca(2+)/calmodulin (CaM)-dependent kinase which can negatively modulate protein synthesis. It is highly conserved among eukaryotes from mammals to invertebrates, of which human and mouse may have 99 % overall amino acid identity. This kinase can phosphorylate eukaryotic elongation factor-2 (eEF2) or undergo the process of autophosphorylation at multiple sites to inhibit its function in translation elongation. Due to the fact that regulation of eEF2 by eEF2K is an evolutionarily conserved mechanism, eEF2K activity may confer tumor cell adaption to metabolic stress under acute nutrient depletion, and the high expressed level of eEF2K has been found in several types of malignancies. eEF2K may modulate the expression of some apoptotic proteins such as XIAP, c-FLIPL, Bcl-XL, PI3KCI and p70(S6K) to inhibit apoptotic process in cancer. On the other hand, it plays a regulatory role in autophagy involved in mTORC1, AMPK and Atg8, thereby promoting cancer cell survival. Additionally, eEF2K may play a crucial role in the crosstalk between apoptosis and autophagy in cancer. Collectively, these findings have led to the conclusions that eEF2K may contribute to carcinogenesis, and thus being utilized as a potential target for future cancer therapy.

Bioinformatic analysis of the effect of type II diabetes on skin wound healing

We examined the relationship between type 2 diabetes and skin wound healing. GSE38396 was downloaded from the Gene Expression Omnibus database and preprocessed using the RMA function of the Affy package. Differentially expressed genes (DEGs) were identified using the limma package, then DAVID was applied to per-form Gene Ontology functional annotation and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis. MicroRNAs and their target genes were screened from the miRecords database and subjected to functional analysis. Finally, the STRING online database was applied to identify the protein-protein interaction relationships, and a combined score > 0.5 was considered to indicate an interaction. A total of 421 DEGs (208 upregulated and 213 downregulated genes) were identified in the skin lymphatic endothelial cells of patients with type II diabetes. Twenty-four microRNAs and 34 target genes were screened, including those involved in cell migration, regulation of cell proliferation, cell death, and cell adhesion regulation, among others. Protein-protein interaction network clustering analysis identified a module composed of 25 genes, and INTERPRO protein domain enrichment analysis showed that the protein domain of the clustering module main-ly contained the insulin-like growth factor binding proteins IGFBP3 and CYR61. IGFBP3 and CYR61 may play important roles in skin wound healing in diabetes patients. This information may be useful for developing methods to treat skin refractory wounds in type II diabetes.

Celastrol induces apoptosis and autophagy via the ROS/JNK signaling pathway in human osteosarcoma cells: an in vitro and in vivo study

Osteosarcoma is the most common primary malignant tumor of bone, the long-term survival of which has stagnated in the past several decades. Celastrol, a triterpene from traditional Chinese medicine, has been proved to possess potent anti-tumor effect on various cancers. However, the effect of celastrol on human osteosarcoma and the underlying mechanisms remains to be elucidated. We reported here that celastrol could inhibit cell proliferation by causing G2/M phase arrest. Exposure to celastrol resulted in the activation of caspase-3, -8, and -9, indicating that celastrol induced apoptosis through both extrinsic and intrinsic pathways. Autophagy occurred in celastrol-treated cells as evidenced by formation of autophagosome and accumulation of LC3B-II. The celastrol-induced cell death was remarkably restored by the combination of autophagy and apoptosis inhibitors. Furthermore, inhibition of apoptosis enhanced autophagy while suppression of autophagy diminished apoptosis. Celastrol also induced JNK activation and ROS generation. The JNK inhibitor significantly attenuated celastrol-triggered apoptosis and autophagy while ROS scavenger could completely reverse them. The ROS scavenger also prevented G2/M phase arrest and phosphorylation of JNK. Importantly, we found that celastrol had the similar effects on primary osteosarcoma cells. Finally, in vivo, celastrol suppressed tumor growth in the mouse xenograft model. Taken together, our results revealed that celastrol caused G2/M phase arrest, induced apoptosis and autophagy via the ROS/JNK signaling pathway in human osteosarcoma cells. Celastrol is therefore a promising candidate for development of antitumor drugs targeting osteosarcoma.

Plant lectins, from ancient sugar-binding proteins to emerging anti-cancer drugs in apoptosis and autophagy

Ubiquitously distributed in different plant species, plant lectins are highly diverse carbohydrate-binding proteins of non-immune origin. They have interesting pharmacological activities and currently are of great interest to thousands of people working on biomedical research in cancer-related problems. It has been widely accepted that plant lectins affect both apoptosis and autophagy by modulating representative signalling pathways involved in Bcl-2 family, caspase family, p53, PI3K/Akt, ERK, BNIP3, Ras-Raf and ATG families, in cancer. Plant lectins may have a role as potential new anti-tumour agents in cancer drug discovery. Thus, here we summarize these findings on pathway- involved plant lectins, to provide a comprehensive perspective for further elucidating their potential role as novel anti-cancer drugs, with respect to both apoptosis and autophagy in cancer pathogenesis, and future therapy.

Key autophagic targets and relevant small-molecule compounds in cancer therapy

Autophagy is a highly conserved lysosomal degradation process which can recycle unnecessary or dysfunctional cell organelles and proteins, thereby playing a crucial regulatory role in cell survival and maintenance. It has been widely accepted that autophagy regulates various pathological processes, among which cancer attracts much attention. Autophagy may either promote cancer cell survival by providing energy during unfavourable metabolic circumstance or can induce individual cancer cell death by preventing necrosis and increasing genetic instability. Thus, dual roles of autophagy may determine the destiny of cancer cells and make it an attractive target for small-molecule drug discovery. Collectively, key autophagy-related elements as potential targets, oncogenes mTORC1, class I PI3K and AKT, as well as tumour suppressor class III PI3K, Beclin-1 and p53, have been discussed. In addition, some small molecule drugs, such as rapamycin and its derivatives, rottlerin, PP242 and AZD8055 (targeting PI3K/AKT/mTORC1), spautin-1, and tamoxifen, as well as oridonin and metformin (targeting p53), can modulate autophagic pathways in different types of cancer. All these data will shed new light on targeting the autophagic process for cancer therapy, using small-molecule compounds, to fight cancer in the near future.

Improved Interfacial Properties of PA6/DE Blends by DE-g-MAH Prepared through Ultrasound Assisted Extrusion

In this paper, ultrasound was applied in extrusion reaction processing to graft an Elastomer (DE) with maleic anhydride (MAH), in order to improve the non-polarity of DE. Two types of DE-g-MAH were prepared by different methods and had similar grafting degree about 0.2 % and then they were added into the polyamide-6/elastomer (PA6/DE) blends, respectively. The effect of DE-g-MAH on the interfacial properties of PA6/DE blends was studied. The experimental results showed that, compared to the DE-g-MAH initiated by peroxide, DE-g-MAH initiated by ultrasound had better effect on refining the particle size of the dispersion phase and keeping the stability of the phase in the blends, which could be confirmed through SEM and Molau tests. When 5 % DE-g-MAH initiated by peroxide was added, the particle size of dispersion phase was 3.90 μm, however, when 5 % DE-g-MAH initiated by ultrasound was added, the particle size of dispersion phase was 2.82 μm. The results of TGA and mechanical tests showed the improved interfacial interaction and enhanced interfacial adhesion of the blend by adding DE-g-MAH, respectively.

Secondary diabetes associated with 5-fluorouracil-based chemotherapy regimens in non-diabetic patients with colorectal cancer: results from a single-centre cohort study

AIM

The aim of the study was to analyse the prevalence and characteristics of secondary diabetes induced by 5-fluorouracil (5-FU) based chemotherapy in non-diabetic patients with colorectal cancer (CRC).

METHOD

A total of 422 consecutive CRC patients who received 5-FU-based chemotherapy were retrospectively analysed. Fasting plasma glucose (FPG) levels were determined before each cycle of chemotherapy during active treatment and regular follow-up. The prevalence and characteristics of secondary hyperglycaemia were investigated, with special focus on the clinical outcome.

RESULTS

Among the 422 CRC patients, 60 had pre-existing hyperglycaemia. In the remaining 362 with normal FPG levels before chemotherapy, 42 (11.6%) and 41 (11.3%) patients developed diabetes and impaired fasting glucose during the study period. Among the 42 secondary diabetic patients, 22 (52.4%) received anti-diabetes drug therapy, in 7 (16.7%) cases the FPG level returned to normal without any active intervention, and 13 (30.9%) cases received diet control and physiotherapy. Thirty-one (8.6%) patients developed diabetes. Based on the Common Terminology Criteria for Adverse Events, an adverse event over Grade 3 occurred in seven cases during follow-up. Diabetes-related adverse events had a serious negative impact on chemotherapy in six cases. Diabetes-related death occurred in three patients.

CONCLUSIONS

Secondary diabetes associated with 5-FU-based chemotherapy occurs in around 10% of CRC patients, with a significant negative impact on treatment and clinical outcome. 5-FU-related diabetes should be regarded as a common side effect of 5-FU treatment.