NUDT15 polymorphisms are better than thiopurine S-methyltransferase as predictor of risk for thiopurine-induced leukopenia in Chinese patients with Crohn's disease

BACKGROUND

Thiopurine-induced leukopenia is the most common dangerous adverse event in Asians. NUDT15 R139C was recently proposed to be a promising biomarker for leukopenia with thiopurine therapy in Asians, but this has not been replicated in the Chinese population.

AIM

To investigate the influence of NUDT15 R139C, thiopurine S-methyltransferase (TPMT), 6-TGN and 6-MMPR on thiopurine-induced leukopenia in Chinese patients with Crohn's disease.

METHODS

Clinical and epidemiological characteristics were reviewed from medical records. NUDT15 R139C and TPMT were genotyped. 6-TGN/6-MMPR concentrations were measured with high-performance liquid chromatography (HPLC).

RESULTS

A total of 253 patients were included, 65 (25.7%) of whom experienced leukopenia. The median follow-up with thiopurine treatment was 38.0 weeks (range, 1-192 weeks). NUDT15 R139C was strongly associated with the incidence of leukopenia (70.2% mutation vs. 12.8% wild type; P=8.61×10^-19 ; odds ratio, 10.80; 95% CI, 5.89-19.83). However, TPMT genotype was not found to be correlated with the incidence of leukopenia (P = 0.44). In subgroup of NUDT15 wild type, there was significant difference of 6TGN concentration between patients with and without leukopenia (413.0 (174.2-831.4) vs. 279.7 (77.3-666.9) pmol/8 × 10⁸ RBC, P = 0.0055). In contrast, no association was found in patients with NUDT15 R139C variant alleles (P = 0.26). 6-MMPR was not correlated with leukopenia (P = 0.84).

CONCLUSIONS

In Chinese patients, it is strongly recommended to detect NUDT15 genotype rather than TPMT before initiating thiopurine drugs. 6TGN concentration should be routinely monitored in CD patients with NUDT15 wild type. As for CT genotype, starting at low dose and careful monitoring for leukopenia and 6TGN levels is recommended.

[Childhood nasal lymphoma:two cases report and literature review]

Here we report two childhood lymphoma cases,which present with a nasal cavity associated with obstructive symptoms and intermittence pyrexia.Application of antibiotic can temporarily alleviate these symptoms but it can not cure this disease radically.Computed tomography of nasopharynx showed inferior turbinate hypertrophy and absence of obvious specific manifestation.The examination of blood and marrow cells did not find any abnormity.The precision diagnostic evaluation is biopsy of clinically involved mass.The definitive pathological diagnosis is NK/T cell lymphoma.The two younger children patients have shorter course of disease,lacking typical cinical presentation and auxiliary examination of it.We should be vigilant whether a child having nasal obstruction and pyrexia is probably NK/T cell lymphoma or not.

Xanthotoxin prevents bone loss in ovariectomized mice through the inhibition of RANKL-induced osteoclastogenesis

Xanthotoxin (XAT) is extracted from the seeds of Ammi majus. Here, we reported that XAT has an inhibitory effect on osteoclastogenesis in vitro through the suppression of both receptor activator of nuclear factor-κB ligand (RANKL)-induced ROS generation and Ca(2+) oscillations. In vivo studies showed that XAT treatment decreases the osteoclast number, prevents bone loss, and restores bone strength in ovariectomized mice.

INTRODUCTION

Excessive osteoclast formation and the resultant increase in bone resorption activity are key pathogenic factors of osteoporosis. In the present study, we have investigated the effects of XAT, a natural furanocoumarin, on the RANKL-mediated osteoclastogenesis in vitro and on ovariectomy-mediated bone loss in vivo.

METHODS

Cytotoxicity of XAT was evaluated using bone marrow macrophages (BMMs). Osteoclast differentiation, formation, and fusion were assessed using the tartrate-resistant acid phosphatase (TRAP) stain, the actin cytoskeleton and focal adhesion (FAK) stain, and the fusion assay, respectively. Osteoclastic bone resorption was evaluated using the pit formation assay. Reactive oxygen species (ROS) generation and removal were evaluated using dichlorodihydrofluorescein diacetate (DCFH-DA). Ca(2+) oscillations and their downstream signaling targets were then detected. The ovariectomized (OVX) mouse model was adopted for our in vivo studies.

RESULTS

In vitro assays revealed that XAT inhibited the differentiation, formation, fusion, and bone resorption activity of osteoclasts. The inhibitory effect of XAT on osteoclastogenesis was associated with decreased intracellular ROS generation. XAT treatment also suppressed RANKL-induced Ca(2+) oscillations and the activation of the resultant downstream calcium-CaMKK/PYK2 signaling. Through these two mechanisms, XAT downregulated the key osteoclastogenic factors nuclear factor of activated T cells c1 (NFATc1) and c-FOS. Our in vivo studies showed that XAT treatment decreases the osteoclast number, prevents bone loss, rescues bone microarchitecture, and restores bone strength in OVX mice.

CONCLUSION

Our findings indicate that XAT is protective against ovariectomy-mediated bone loss through the inhibition of RANKL-mediated osteoclastogenesis. Therefore, XAT may be considered to be a new therapeutic candidate for treating osteoporosis.

Dihydroartemisinin attenuates lipopolysaccharide-induced osteoclastogenesis and bone loss via the mitochondria-dependent apoptosis pathway

Dihydroartemisinin (DHA) is a widely used antimalarial drug isolated from the plant Artemisia annua. Recent studies suggested that DHA has antitumor effects utilizing its reactive oxygen species (ROS) yielding mechanism. Here, we reported that DHA is inhibitory on lipopolysaccharide (LPS)-induced osteoclast (OC) differentiation, fusion and bone-resorption activity in vitro. Intracellular ROS detection revealed that DHA could remarkably increase ROS accumulation during LPS-induced osteoclastogenesis. Moreover, cell apoptosis was also increased by DHA treatment. We found that DHA-activated caspase-3 increased Bax/Bcl-2 ratio during LPS-induced osteoclastogenesis. Meanwhile, the translocation of apoptotic inducing factor (AIF) and the release of cytochrome c from the mitochondria into the cytosol were observed, indicating that ROS-mediated mitochondrial dysfunction is crucial in DHA-induced apoptosis during LPS-induced osteoclastogenesis. In vivo study showed that DHA treatment decreased OC number, prevents bone loss, rescues bone microarchitecture and restores bone strength in LPS-induced bone-loss mouse model. Together, our findings indicate that DHA is protective against LPS-induced bone loss through apoptosis induction of osteoclasts via ROS accumulation and the mitochondria-dependent apoptosis pathway. Therefore, DHA may be considered as a new therapeutic candidate for treating inflammatory bone loss.

Association between DEFB103 gene copy number variation and ankylosing spondylitis: a case-control study

In this brief communication, we investigate the role of DEFB103 gene copy number variation (CNV) in ankylosing spondylitis (AS) susceptibility. A total of 807 Chinese individuals including 406 AS patients and 401 controls were enrolled. The DEFB103 copy number was measured by two sets of probes to obtain a stable result in a custom-by-design Multiplex AccuCopy(™) kit (Genesky Biotechnologies Inc., Shanghai, China) based on a multiplex fluorescence competitive polymerase chain reaction (PCR) principle. The copy number of DEFB103 ranged from 2 to 6 in both AS patients and controls. Mann-Whitney U test and chi-squared test were performed to analyze the difference of DEFB103 copy number between AS patients and controls while no statistical difference has been found. We considered the copy number of DEFB103 gene may not associate with susceptibility to AS.

Differential gene expression in pre-laying and laying period ovaries of Sichuan White geese (Anser cygnoides)

Geese are an economically important poultry species worldwide. Their superior meat production performance and meat qual-ity make them a popular food. However, they are not bred worldwide because their poor laying capacity increases farming costs. To gain a global view of the genes that are differentially expressed between pre-laying (P) and laying (L) periods and to develop a database for further studies, we performed large-scale transcriptome sequencing of ovarian tissue collected from Anser cygnoides. In total, 30,151,422 raw reads, with an average length of 151 bp and a total length of 4,552,864,722 bp, were obtained. After primers and adaptors were removed, 19,167,132 clean reads, with an average length of 134.5 bp and a total length of 2,577,297,281 bp, were obtained, among which 1,268,906,694 bp and 1,308,390,587 bp were from L and P ovarian tissue, respectively. The 16,605 assembled sequences were further functionally annotated by comparing their sequences to different protein and functional domain databases and assigning gene ontology (GO) terms. Of these, 511 as-sembled sequences were considered differentially expressed based on the 2-fold method, among which 396 were assigned at least one GO term. Digital expression analysis using the Kyoto encyclopedia of genes and genomes annotation identified 121 genes that were differ-entially expressed in the P vs L periods. Five of these are of special interest for further investigation of their roles in determining high re-productive performance. This study provides valuable information and sequence resources for uncovering genes determining high egg-laying performance and for future functional genomics analysis of geese.

FOXC2 promotes chemoresistance in nasopharyngeal carcinomas via induction of epithelial mesenchymal transition

Paclitaxel (Taxol) is currently used as the front-line chemotherapeutic drug for many types of human cancers. However, the emergence of drug resistance has been a major obstacle to the effective treatment of cancers in clinical settings. The transcription factor Forkhead box protein C2 (FOXC2) was recently demonstrated to activate the epithelial-mesenchymal transition (EMT). In this article, we present a novel role of FOXC2 in regulating chemoresistance of nasopharyngeal carcinoma (NPC) through the EMT. Using an EMT PCR array based on the screening of 84 genes, the expression of FOXC2 was notably upregulated in paclitaxel-resistant NPC cells (CNE2/t). We observed that the paclitaxel-resistant cells exhibited characteristic EMT phenotypes. The silencing of FOXC2 expression in the resistant cells can reverse the EMT molecular markers and chemoresistant phenotypes, such as cellular morphology, proliferation and anoikis. In an NPC xenograft mouse model, the downregulation of FOXC2 expression in the resistant NPC cells increased their sensitivity to paclitaxel treatment, resulting in reduced tumor growth. Taken together, our results suggest that FOXC2-mediated EMT may be an alternative mechanism through which cancer cells can initiate and maintain drug resistance. Thus, targeting FOXC2 may provide a novel strategy for overcoming chemoresistance in NPC therapy.

3-T diffusion tensor imaging (DTI) of normal uterus in young and middle-aged females during the menstrual cycle: evaluation of the cyclic changes of fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values

OBJECTIVE

To evaluate cyclic changes of fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of normal uterus in different age groups during the menstrual cycle, and the correlation with serum female hormone levels.

METHODS

29 normal volunteers accepted diffusion tensor imaging of the uterus on menstrual phase (MP), follicular phase (FP), ovulatory phase (OP) and luteal phase. FA and ADC values of different uterine layers on midsagittal images were measured. Differences between two age groups during the menstrual cycle were evaluated using liner mixed models and one-way analysis of variance. Pearson correlation analysis compared variation of FA and ADC values with serum female hormone levels measured in MP.

RESULTS

During menstrual cycle, endometrial FA values declined, whereas ADC values increased with significant differences (p < 0.05). Serum oestradiol (E) levels correlated moderately with variations of FA values between MP-FP (p = 0.045; r = 0.389) and MP-OP (p = 0.008; r = 0.511). FA and ADC values of junctional zones showed no significant difference (p > 0.05) as well as FA values of myometrium (p = 0.0961), while ADC values of myometrium showed significant increase from menstrual phase to luteal phase (p < 0.05). FA and ADC values of uterine three zonal structures showed significant differences (p < 0.05) at each phase during the menstrual cycle. No significant difference of FA and ADC values was found between age groups (p > 0.05).

CONCLUSION

Dynamic changes of uterine FA and ADC values were observed during menstrual cycle. Variation of FA values between MP-FP, MP-OP correlated moderately with serum E levels.

ADVANCES IN KNOWLEDGE

No publications on the relationship between FA and ADC values and the female hormone levels were found; our study prospectively investigated the cyclic changes of FA and ADC values of the normal uterus and the correlation with the basic serum female hormone levels in MP.

Comparative analysis of MCP-1 and TF in elderly patients with acute exacerbations of COPD and its clinical significance

OBJECTIVE

This study was conducted to investigate the variation of monocyte chemoattrant protein-1 (MCP-1) and tissue factor (TF) in elderly patients with acutely exacerbated chronic obstructive pulmonary disease (AECOPD) and their clinical significance.

PATIENTS AND METHODS

Serum specimens were obtained from 49 AECOPD. Patients and 30 health controls, with mean age of 76.1 ± 10.2 and 62.8 ± 6.5 years. Patients in AECOPD group were further grouped into two subgroups, with high or normal procaletonin (PCT) levels. Plasma TE, MCP-1 and PCT were qualified by enzyme-linked immunosorbent assay (ELISA).

RESULTS

TF and MCP-1 were found to be higher in AECOPD patients than in health people (p < 0.01), and TF was linearly and positively related to MCP-1. In the subgroups TF was significantly higher in patients with higher PCT than those with normal PCT (p < 0.05).

CONCLUSIONS

In AECOPD patients blood cells are activated to hypercoagulation state, particularly when their PCT level is high. Extrinsic pathway activated by TE plays important role in development of the hypercoagulation state. Our results indicate that plasma TF level was positively correlated to the level of MCP-1. This suggests that monitoring of plasma TF and MCP-1 levels in AECOPD patients could be a very useful way to prevent and cure blood hypercoagulability, cardiovascular and cerebrovascular thrombotic diseases.

Respiratory cancers and pollution

Cancer is the major public health problem worldwide, irrespective of the socio-economic status of the countries. Even though the overall mortality from cancer is higher in the western countries, the cancer burden is on the rise in under-developed countries, with a projected 81-100% increase by 2030, mostly due to pollution and tobacco use. Respiratory cancers affect the lung, larynx, trachea, and bronchus and depending on the location of the cancer, the symptoms change and also the risks, incidence and survival outcomes differ accordingly. Besides tobacco use, chronic exposure to household pollution is known to be associated with elevated risk of lung cancer and other cancers. Women and children living in severe poverty in the underdeveloped countries are exposed most to household air pollution and, thus, suffer its consequences maximally, and household air pollution, specifically arising from solid fuel burning, which accounts for nearly 4 million deaths throughout the world annually. Cancers affecting the respiratory tract, including both nasopharyngeal cancer and lung cancer, are strongly associated with pollution from coal and other solid fuel burning. Lung cancer, which is of two types, small cell lung carcinoma and the non-small cell lung cancer, is the most common and fatal cancer. Even though tobacco has been viewed as the major risk for respiratory cancers, it is now evident that household pollution, exposure to asbestos, chromium and arsenic etc, all pose a significant risk for respiratory cancers. Preventive steps to curtail the many sources of air pollution by improving living conditions and reducing the occupational exposure hazards like welding, industrial work etc., are markedly needed to control the incidence of respiratory cancers.

Reversal of multidrug resistance by gefitinib via RAF1/ERK pathway in pancreatic cancer cell line

Pancreatic cancer is a devastating malignancy, characterized by intrinsic or acquired resistance to conventional chemotherapies. Recent evidences suggest an involvement of tyrosine kinase pathway in the regulation of multidrug resistance (MDR) protein gene expression. The aim of this study was to test whether gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor could regulate the MDR protein gene expression and sensitize the resistant cancer cells to chemotherapy. The gene expression of MDR proteins (MRP1, MRP2, MRP3, and PGP) were evaluated by quantitative RT-PCR, and expression levels of various tyrosine kinases were investigated by quantitative RT-PCR and Western blot in pancreatic cancer cell line. MTT assay was used for evaluating the effect of chemotherapeutic agents. Chemotherapeutics induced drug resistance by regulating the gene expression of MDR proteins (MRP1, MRP2, and MRP3), and increased the gene expression of RAF1/ERK and the phosphorylation of ERK in pancreatic cancer Bxpc-3 cells. Gefitinib caused an inhibition of p-ERK tyrosine kinase activation in a dose-dependent manner, and reversed gemcitabine-induced RAF1/ERK gene expression and p-ERK activation. In addition, a reversal of MDR proteins gene expression was achieved by gefitinib, which sensitized resistant cells to gemcitabine. This study demonstrated that MDR of Bxpc-3 cell is involved in the RAF1/ERK tyrosine kinase pathway. Gefitinib reverses the MDR protein gene expression and restores sensitivity of resistant cells to gemcitabine via RAF1/ERK signaling pathway. Combination of gefitinib with conventional chemotherapeutic agents may offer a new approach for the treatment of patients with pancreatic cancer.

Hepatitis B virus genotype and basal core promoter/precore mutations are associated with hepatitis B-related acute-on-chronic liver failure without pre-existing liver cirrhosis

The study was undertaken to investigate the features and clinical implications of hepatitis B virus (HBV) genotypes, basal core promoter (BCP) and precore (PC) mutations in hepatitis B-related acute-on-chronic liver failure (HB-ACLF). Samples from 75 patients with HB-ACLF and without pre-existing liver cirrhosis and 328 age-matched patients with chronic hepatitis B (CHB) were analyzed. HBV genotype and BCP/PC mutations were determined by direct sequencing. Mutations at 8 sites of the BCP/PC region were compared between the two groups of patients. A significantly higher ratio of genotype B to C was found in patients with HB-ACLF than in patients with CHB (30.7-69.3% vs 16.5-82.6%, P < 0.01). Single mutations including T1753V (C/A/G), A1762T, G1764A, G1896A and G1899A and triple mutations T1753V/A1762T/G1764A and A1762T/G1764A/C1766T (or T1768A) were more frequently detected in patients with HB-ACLF than in patients with CHB. Correspondingly, BCP/PC wild-type sequences were absent in patients with HB-ACLF in contrast to 27.1% in patients with CHB. The BCP/PC mutations were found to be associated with increased HBeAg negativity, higher alanine aminotransferase level and lower viral load. Patients with HB-ACLF infected with the PC mutant virus had a higher mortality. The findings suggest that patients with CHB infected with genotype B with BCP/PC mutations were more likely to develop HB-ACLF than those with genotype C with wild-type BCP/PC regions, and patients with HB-ACLF with the PC mutation had increased risk of a fatal outcome.

A 6-bp deletion in the TYRP1 gene causes the brown colouration phenotype in Chinese indigenous pigs

Brown coat colour has been described in Chinese-Tibetan, Kele, and Dahe pigs. Here, we report the identification of a causal mutation underlying the brown colouration. We performed a genome-wide association study (GWAS) on Tibetan and Kele pigs, and found that brown colours in Chinese breeds are controlled by a single locus on pig chromosome 1. By using a haplotype-sharing analysis, we refined the critical region to a 1.5-Mb interval that encompasses only one pigmentation gene: tyrosinase-related protein 1 (TYRP1). Mutation screens of sequence variants in the coding region of TYRP1 revealed a strong candidate causative mutation (c.1484_1489del). The protein-altering deletion showed complete association with the brown colouration across Chinese-Tibetan, Kele, and Dahe breeds by occurring exclusively in brown pigs (n=121) and lacking in all non-brown-coated pigs (n=745) from 27 different breeds. The findings provide the compelling evidence that brown colours in Chinese indigenous pigs are caused by the same ancestral mutation in TYRP1. To our knowledge, this study gives the first description of GWAS identifying causal mutation for a monogenic trait in the domestic pig.

Genome-wide identification of quantitative trait loci for carcass composition and meat quality in a large-scale White Duroc x Chinese Erhualian resource population

Carcass and meat quality traits are economically important in pigs. In this study, 17 carcass composition traits and 23 meat quality traits were recorded in 1028 F(2) animals from a White Duroc x Erhualian resource population. All pigs in this experimental population were genotyped for 194 informative markers covering the entire porcine genome. Seventy-seven genome-wide significant quantitative trait loci (QTL) for carcass traits and 68 for meat quality were mapped to 34 genomic regions. These results not only confirmed many previously reported QTL but also revealed novel regions associated with the measured traits. For carcass traits, the most prominent QTL was identified for carcass length and head weight at 57 cM on SSC7, which explained up to 50% of the phenotypic variance and had a 95% confidence interval of only 3 cM. Moreover, QTL for kidney and spleen weight and lengths of cervical vertebrae were reported for the first time in pigs. For meat quality traits, two significant QTL on SSC5 and X were identified for both intramuscular fat content and marbling score in the longissimus muscle, while three significant QTL on SSC1 and SSC9 were found exclusively for IMF. Both LM and the semimembranous muscle showed common QTL for colour score on SSC4, 5, 7, 8, 13 and X and discordant QTL on other chromosomes. White Duroc alleles at a majority of QTL detected were favourable for carcass composition, while favourable QTL alleles for meat quality originated from both White Duroc and Erhualian.

The 5' untranslated region of fruA mRNA is required for translational enhancement of FruA synthesis during Myxococcus xanthus development

The fruA gene encodes a DNA-binding response regulator protein essential for the development of Myxococcus xanthus. This gene is transcribed with an unusually long (235 nucleotides) 5' untranslated region (UTR) that has been shown to be absolutely necessary for the induction of FruA synthesis during development. With lacZ as a reporter, it was found in this report that each regional deletion mutation within 5' UTR caused a decrease in beta-galactosidase production. Base substitution mutations that were designed to alter local stem-loop structures also decreased fruA-lacZ expression, however their compensatory mutations could not rescue fruA-lacZ expression at all. A moderate decrease in beta-galactosidase activity was observed from the fruA-lacZ transcriptional fusion lacking fruA 5' UTR; in contrast, expression of the fruA-lacZ translational fusion lacking the 5' UTR was severely impaired. In addition, both the amount and stability of fruA-lacZ mRNA were just moderately reduced in the absence of this 5' UTR. These results suggest that the function of the 5' UTR of fruA mRNA requires integrity of almost the entire region and may depend on the primary sequence. More importantly, fruA 5' UTR modulates the expression of its own gene mainly by enhancing translation efficiency of the transcript.

[In situ FTIR studies of CO adsorption on palladium loading zeolite electrode]

Adsorption of CO on palladium loading zeolite electrode supported on Pt or GC substrate was studied by in situ MSFTIR spectroscopy. The results demonstrated that the geometry of faujasite supercages favors the formation of bridge-bonded CO species. The enhanced IR adsorption of CO adsorbed on Pd clusters located in the supercages of zeolite has been observed for the first time, which is a new phenomenon and differs from the abnormal infrared effects discovered by our group and the surface enhanced infrared absorption phenomenon reported in the literature.

[The relationship of lung function and heart function of RHD patients in different period]

OBJECTIVE

To investigate the relationship of heart function and lung function in RHD patients.

METHODS

We compared heart posterior-anterior film, lung function test results, PaO(2) and O(2) Sat of blood gas analysis before and after motion before operation, early postoperation, late postoperation, according to heart function and cardiothoracic ratio in 98 RHD patients.

RESULTS

With worsening of heart function and enlargement of cardiothoracic ratio, lung function worsened too. PaO(2) and O(2) Sat did not change apparently. The lung function of early postoperation did not improve significantly. The lung function improved gradually with better heart function and shortening of heart in later postoperation. But small air way obstruction and diffuse function and function residue volume changed slowly.

CONCLUSIONS

Heart function affects the lung function directly. They were positively correlated.

[In vitro toxicity evaluation of 12 kinds of dental materials using a modified cell culture technique]

In view of the fact that up to date the various cell toxicity tests could not come to an identical result and compare with each other. This paper, referring to the covering documents of F.D.I. and I.S.O., summing up the principles and characteristics of various cell culture techniques, establishes a modified cell toxicity test. This method, with more respects of wide observations and tangible results, is easy to grasp, well to repeat and can be reserved for checking the results, meanwhile, it can be avoided the contradiction caused by the different experiments on one kind of material. Therefore, it is very worthy of appraising the biological safety of the materials. The study of 12 kinds of dental materials expressed that the toxicity order of copper alloy was mean value of 0 (Jiao Tong University), copper alloy tridium was mean value of 3 (U.S.A.), copper alloy T was mean value of 2 (Jiao Tong University) and the others were mean value of 0-1. This paper also discussed several problems with common concerns in studying the cell toxicity of the biomaterials.