Engineering D-helix of antithrombin in alpha-1-proteinase inhibitor confers antiinflammatory properties on the chimeric serpin

Antithrombin (AT) is a heparin-binding serpin in plasma which regulates the proteolytic activity of procoagulant proteases of the clotting cascade. In addition to being an anticoagulant, AT also exhibits antiinflammatory activities when it binds to cell surface heparan sulfate proteoglycans (HSPGs) on the endothelium via its basic residues of D-helix to elicit intracellular signalling responses. By contrast to AT, α1-proteinase inhibitor (α1-PI) is a non-heparin-binding serpin that exhibits very slow reactivity with coagulation proteases and possesses no HSPG-dependent antiinflammatory properties. To determine whether the antiinflammatory signaling specificity of AT can be transferred to α1-PI, we replaced the D-helix of human α1-PI with the corresponding sequence of human AT and expressed the chimeric serpin α1-PI/D-helix) in a bacterial expression system. High molecular weight heparin bound to α1-PI/D-helix and accelerated the inhibition of thrombin by the serpin mutant by a template mechanism reminiscent of the cofactor effect of heparin on inhibition of thrombin by AT. Like AT, α1-PI/D-helix exhibited antiinflammatory properties in both cellular and animal models. Thus, α1-PI/D-helix inhibited the barrier-disruptive effect of proinflammatory cytokines and inhibited the activation of nuclear factor-κB transcription factor in lipopolysaccharide-stimulated endothelial cells by a concentration-dependent manner. Furthermore, the chimeric serpin reduced lipopolysaccharide-mediated lethality, elicited a vascular protective effect and inhibited infiltration of activated leukocytes to the peritoneal cavity of mice in an HMGB1-mediated inflammatory model. These results suggest that grafting the D-helix of AT to α1-PI confers antiinflammatory properties on the serpin and that the chimeric serpin may have therapeutic utility for treating inflammatory disorders.

First Report of Sclerotinia minor on Brassica rapa subsp. pekinensis in Central China

Chinese cabbage (Brassica rapa subsp. pekinensis Hanelt) is a leafy vegetable widely grown in China. In December 2012 to March 2013, a leaf rot disease was observed on the lower part of cabbage leaves in a field in Xianning, Hubei Province, China, with the incidence of 6.3% in that field. The diseased leaves showed water-soaked rot and brown symptoms at the top surface. White fluffy mycelia and small black sclerotia were produced on the lesion surface. Cabbage leaf tissues from the disease/healthy-bordering areas and the sclerotia from the lesions were separately surface-sterilized in 75% ethanol (v/v) for 30 s, followed by rinsing three times in sterilized water. The surface-sterilized tissues and sclerotia were placed on potato dextrose agar (PDA) and incubated at 22°C. Individual emerging fungal colonies from the leaf tissue pieces and the sclerotia were transferred to new 9-cm-diameter PDA plates and incubated for 15 days. A total of 40 isolates (20 from diseased tissue and 20 from sclerotia) were obtained. All the isolates grew rapidly on PDA with an average growth rate of 2.2 cm/day and produced abundant sclerotia on the colony surface (1,179 sclerotia/plate on average). None of the isolates produced conidia and any other spores in the PDA cultures. Mature sclerotia were black, irregular, spherical or elliptical, had a diameter of 0.5 to 1 mm, and easily detached from the colonies. The cultural and morphological characteristics of the isolates matched the description for Sclerotinia minor Jagger (3). Two isolates, A1 (from leaf tissue) and S2 (from a sclerotium), were further identified by analysis of the ITS region (ITS1-5.8S rDNA-ITS2) using the primer pair ITS1/ITS4. The resulting 540-bp DNA sequences (GenBank Accession Nos. KC836493 for A1 and KC836494 for S2) shared 100% identity S. minor isolate 62907 (JF279880). Pathogenicity of the isolates A1 and S2 was tested by inoculating detached cabbage leaves with mycelial agar plugs removed from the colony margin of the 3-day-old cultures. Isolates A1 and S2 were each inoculated on three leaves with three plugs per leaf. Three cabbage leaves inoculated with PDA plugs were treated as a control. The treated leaves were covered with plastic films to maintain high humidity (>90% RH) and incubated at 22°C for 72 h under the regime of 12 h light/12 h dark. Results showed that while the control leaves remained healthy, brown and water-soaked lesions appeared around the mycelial agar plugs of each isolate. Average lesion diameters were 47.5 mm for A1 and 47.8 mm for S2. Abundant small sclerotia were produced on necrotic leaf lesions after 7 days. The fungus in diseased leaf tissues was re-isolated and the morphological characteristics of the resulting fungus were the same as S. minor isolated from infected field-grown cabbages. Therefore, S. minor is the causal agent for the leaf rot disease on Chinese cabbage. S. minor has been reported to infect a few plant species in the genus Brassica, including B. rapa subsp. oleifera (3), B. oleracea var. gemmifera (3), B. napus (2), B. oleracea var. capitata (3), B. oleracea var. botrytis (3), and B. rapa (3). It was found on B. rapa subsp. pekinensis in Korea (1). To our knowledge, this is the first report of S. minor on B. rapa subsp. pekinensis in China. References: (1) W. D. Cho and H. D. Shin. Page 779 in: List of Plant Diseases in Korea, 4th ed. Korean Society of Plant Pathology, 2004. (2) S. A. Gaetán and M. Madia. Plant Dis. 92:172, 2008. (3) M. S. Melzer et al. Can. J. Plant Pathol. 19:272, 1997.

First Report of Leptosphaeria biglobosa Causing Black Leg on Raphanus sativus in Central China

Chinese radish (Raphanus sativus) is an important vegetable grown widely in China. In 2010 to 2013, surveys for Leptosphaeria spp. on cruciferous vegetables were conducted in 17 counties in Hubei Province, China. Black leg symptoms on tuber roots and basal stems of radish were observed in Hanchuan, Jingmen, and Macheng counties. Disease incidence ranged from 2 to 25% in 10 surveyed radish fields. Five fungal isolates were obtained from diseased radish plants by surface-sterilizing radish tissue (5% NaOCl for 90 s, and then rinsed in sterilized water three times) and plating onto potato dextrose agar (PDA) plates incubated at 20°C. The isolations produced fluffy white colonies with a yellow pigment, and black-brown, globose pycnidia with pink conidial ooze formed after 10 days. Pycnidia were 150 to 200 × 80 to 100 μm. Conidia were hyaline, cylindrical, and 4 to 5 × 2 μm. The cultural and morphological characteristics of the isolates matched the description for Phoma lingam, anamorph of Leptosphaeria maculans and L. biglobosa (3). All five isolates were identified by PCR assay using the species-specific primers LbigF, LmacF, and LmacR (1), and isolate HCLB-1 was identified further by PCR cloning and analysis of the sequences coding for actin, β-tubulin, and the internal transcribed spacer (ITS) region of ribosomal DNA (3,4). Genomic DNA was extracted from mycelium of each isolate harvested from 7-day-old cultures in V8 broth using the CTAB method (5). A 444-bp DNA fragment was detected by PCR assay, suggesting that all five isolates belonged to L. biglobosa rather than L. maculans as the latter generates a 331-bp DNA fragment (1). The HCLB-1 sequences for ITS (587 bp, GenBank Accession. No. KC880981), actin (899 bp, KF307762), and β-tubulin (432 bp, KF220296) genes were 99 to 100% identical to those of L. biglobosa isolates in GenBank. All five isolates were tested for pathogenicity on R. sativus cultivars Duan Ye 13 and Qi Ye Hong. Cotyledons of 10-day-old radish seedlings and post-harvest mature roots were wounded using a sterilized needle, and 10 μl of a conidial suspension (1 × 10⁷ conidia/ml) of each isolate was pipetted onto the wounded area on each cotyledon or root, respectively, with 12 cotyledons (= 24 wounded sites) and 1 root (= 6 wounded sites) inoculated/isolate. One wounded root and 12 wounded cotyledons inoculated with water were used as control treatments. Treated roots and seedlings were incubated at 20°C and 100% RH in the dark for 7 days, and under a 12 h light/12 h dark cycle for 12 days, respectively. While the control roots and cotyledons remained asymptomatic, the roots and cotyledons inoculated with all five test isolates formed black cankers and necrotic lesions, respectively, in the inoculated wounds. A fungus re-isolated from symptomatic roots and cotyledons resembled the original isolates in colony morphology and the 444-bp DNA fragment detected by PCR assay. No fungus was isolated from control seedlings or roots. Thus, L. biglobosa appears to be the causal agent of black leg observed on radish in Hubei, China. L. biglobosa was reported to infect wild radish (R. raphanistrum) (2). To our knowledge, this is the first report of L. biglobosa causing black leg on R. sativus. References: (1) S. Y. Liu et al. Plant Pathol. 55:401, 2006. (2) A. Maxwell and J. K. Scott. Australas. Plant Pathol. 37:523, 2008. (3) L. Vincenot et al. Phytopathology 98:321, 2008. (4) T. J. White et al. PCR Protocols: A Guide to Methods and Applications, Academic Press, 1990. (5) J. Zhang et al. Mycologia 102:1114, 2010.

Observation of η'→π+ π π+ π- and η'→π+π- π0 π0

Using a sample of 1.3 × 10(9)  J/ψ events collected with the BESIII detector, we report the first observation of η(')→π(+)π(-)π(+)π(-) and η(')→π(+)π(-)π(0)π(0). The measured branching fractions are B(η(')→π(+)π(-)π(+)π(-)) = [8.53 ± 0.69(stat.) ± 0.64(syst.)]×10(-5) and B(η(')→π(+)π(-)π(0) π(0)) = [1.82 ± 0.35(stat.) ± 0.18(syst.)] × 10(-4), which are consistent with theoretical predictions based on a combination of chiral perturbation theory and vector-meson dominance.

Nitric oxide is a positive regulator of the Warburg effect in ovarian cancer cells

Ovarian cancer (OVCA) is among the most lethal gynecological cancers leading to high mortality rates among women. Increasing evidence indicate that cancer cells undergo metabolic transformation during tumorigenesis and growth through nutrients and growth factors available in tumor microenvironment. This altered metabolic rewiring further enhances tumor progression. Recent studies have begun to unravel the role of amino acids in the tumor microenvironment on the proliferation of cancer cells. One critically important, yet often overlooked, component to tumor growth is the metabolic reprogramming of nitric oxide (NO) pathways in cancer cells. Multiple lines of evidence support the link between NO and tumor growth in some cancers, including pancreas, breast and ovarian. However, the multifaceted role of NO in the metabolism of OVCA is unclear and direct demonstration of NO's role in modulating OVCA cells' metabolism is lacking. This study aims at indentifying the mechanistic links between NO and OVCA metabolism. We uncover a role of NO in modulating OVCA metabolism: NO positively regulates the Warburg effect, which postulates increased glycolysis along with reduced mitochondrial activity under aerobic conditions in cancer cells. Through both NO synthesis inhibition (using L-arginine deprivation, arginine is a substrate for NO synthase (NOS), which catalyzes NO synthesis; using L-Name, a NOS inhibitor) and NO donor (using DETA-NONOate) analysis, we show that NO not only positively regulates tumor growth but also inhibits mitochondrial respiration in OVCA cells, shifting these cells towards glycolysis to maintain their ATP production. Additionally, NO led to an increase in TCA cycle flux and glutaminolysis, suggesting that NO decreases ROS levels by increasing NADPH and glutathione levels. Our results place NO as a central player in the metabolism of OVCA cells. Understanding the effects of NO on cancer cell metabolism can lead to the development of NO targeting drugs for OVCAs.

Genetic tuning of the novel avian influenza A(H7N9) virus during interspecies transmission, China, 2013

A novel avian influenza A(H7N9) virus causing human infection emerged in February 2013 in China. To elucidate the mechanism of interspecies transmission, we compared the signature amino acids of avian influenza A(H7N9) viruses from human and non-human hosts and analysed the reassortants of 146 influenza A(H7N9) viruses with full genome sequences. We propose a genetic tuning procedure with continuous amino acid substitutions and reassorting that mediates host adaptation and interspecies transmission. When the early influenza A(H7N9) virus, containing ancestor haemagglutinin (HA) and neuraminidase (NA) genes similar to A/Shanghai/05 virus, circulated in waterfowl and transmitted to terrestrial poultry, it acquired an NA stalk deletion at amino acid positions 69 to 73. Then, receptor binding preference was tuned to increase the affinity to human-like receptors through HA G186V and Q226L mutations in terrestrial poultry. Additional mammalian adaptations such as PB2 E627K were selected in humans. The continual reassortation between H7N9 and H9N2 viruses resulted in multiple genotypes for further host adaptation. When we analysed a potential association of mutations and reassortants with clinical outcome, only the PB2 E627K mutation slightly increased the case fatality rate. Genetic tuning may create opportunities for further adaptation of influenza A(H7N9) and its potential to cause a pandemic.

Characterization of Killer cell immunoglobulin-like receptor (KIR) genotypes and haplotypes in Chinese Han population

We performed Killer cell immunoglobulin-like receptor (KIR) genotyping on 1271 individuals of Chinese Han origin including 102 families and 965 unrelated individuals. The families (with one child and both parents) were subjected for haplotype analysis. Forty-one different genotypes were identified. The frequencies of the KIR genotypes found in the family panel were confirmed by those found in the unrelated panel. The family study showed segregation of one A haplotype and at least 15 unique B haplotypes. The most commonly observed haplotypes in group B were B1, B2, and B3, present at a frequency of 10.05%, 6.62%, and 4.90%, respectively. On the basis of the combination of KIR genes, six centromeric and seven telomeric gene motifs have been identified. Motif cB02 was the most frequent haplotype B specific centromeric segment while tB01 was the most frequent haplotype B specific telomeric segment. The distinct distribution of KIR haplotypes in each population may reflect the history of directional and balancing selection of different races. The gene combinations of group A and B1/B2/B3 haplotype were the most frequent genotypes named as Bx1, Bx2, and Bx3, present at a frequency of 13.72%, 7.35%, and 4.41% in the family panel, and at a frequency of 15.86%, 10.15%, and 5.80% in the unrelated panel, respectively. Overall, this study showed the diversity of KIR haplotypes and genotypes in Chinese Han population and developed a criterion for distinguish KIR haplotypes/genotypes for the population. KIR genotyping and haplotype analysis should be useful for selection of the most optimum donor grafts with favorable KIR gene content for transplants.

Bacteria in hernia sac: an important risk fact for surgical site infection after incarcerated hernia repair

BACKGROUND

Although some recent reports have proven that incarcerated and/or strangulated hernia is not contraindication to mesh repair, there is still a common concern owing to increased rate of postoperative surgical site infection (SSI). The aim of this clinical study was to evaluate factors that increase the risk of SSI after incarcerated hernia repair, and to identify the pathogens related to SSI.

METHODS

A retrospective analysis was performed on data collected prospectively over a 4-year interval from January 2007 to December 2011. A total of 121 patients who underwent emergency surgery for incarcerated hernias were analyzed.

RESULTS

107 hernias were repaired using mesh versus 14 primary suture repairs. SSIs were observed in 9 of the 121 patients. Of 15 preoperative and intraoperative variables studied, duration of symptoms, diabetes mellitus, present of ileus, bowel resection or mesh repair performed, bacteria present in hernia sac and cloudy fluid in hernia sac were found to be significant factors predicting SSI. On multivariate analysis only bowel resection, duration of symptoms and bacteria present in hernia sac were independent variables. The most common pathogen found in hernia sac and cultured from wound drainage or swab was Escherichia coli. The strains of bacteria cultured from wound drainage or swab were same as those cultured from fluid in hernia sac in six of nine patients.

CONCLUSION

Gut-sourced E. coli is an important common organisms associated with SSI after incarcerated hernia repair. Prosthetic mesh could be used when no bowel resection is performed, duration of symptoms less than 24 h and fluid hernia sac is clear.

Platelet factor 4 protects bone marrow mesenchymal stem cells from acute radiation injury

OBJECTIVE

The aim of this study was to find a new radiation protector, platelet factor 4 (PF4) and to identify its effect on haemopoietic microenvironment in vitro and in vivo.

METHODS

Radiation damage on bone marrow mesenchymal stem cells ex and in vitro was set up as models. Growth curve analysis, clonogenic survival assay, FACSCalibur™ (BD Immunocytometry Systems, San Jose, CA), 5-ethynyl-2'-deoxyuridine immunofluorescence staining and quantitative reverse transcription-polymerase chain reaction were employed to assess the characterization of bone marrow mesenchymal stem cells (BMSCs), proliferation, apoptosis, cell cycle and gene expression.

RESULTS

A dose- and time-dependent enhancement of cell viability and survival was observed for PF4 treatment along with 500 cGy γ-radiation in vitro. The same phenomena were noted in vivo, including enhancement of adherence and proliferation ability while inhibition of cell apoptosis, which were associated with a short-term decrease in the G0/G1 ratio owing to S phase arrest. These were accompanied with enhanced Bcl-2 expression and p53/p21 loss.

CONCLUSION

These results uncover that PF4 might be a novel therapeutic approach, which could reduce DNA damage and increase survival of BMSCs, in part, by inhibiting p53/p21 axis and facilitating DNA damage repair.

ADVANCES IN KNOWLEDGE

This study explores the feasibility of a new radioprotector and hence may be clinically important.

Collision of counterpropagating laser-excited wake bubbles

The collision of wake bubbles behind two counterpropagating laser pulses in rarefied plasma is investigated using particle-in-cell simulation. Special attention is paid to the highly nonlinear dynamics of the electrons in the interaction region. It is found that, as the two bubbles approach each other and collide, the electrons in the interaction region first oscillate in a periodic fashion, forming a quasistationary dense electron density ripple with fairly regular spatial structure. At longer times, the electron motion becomes chaotic, and the density grating is gradually smeared. The electrons escape in the transverse direction, and eventually the two bubbles merge to form a single one. The transition of the electron motion from regular to chaotic is confirmed by analytical modeling using test electrons moving in counterpropagating planar electromagnetic waves. The findings shed light on the dynamics of wake-bubble collisions and the complex behavior induced by multiple laser pulses in plasmas.

A combined compensation method for the output voltage of an insulated core transformer power supply

An insulated core transformer (ICT) power supply is an ideal high-voltage generator for irradiation accelerators with energy lower than 3 MeV. However, there is a significant problem that the structure of the segmented cores leads to an increase in the leakage flux and voltage differences between rectifier disks. A high level of consistency in the output of the disks helps to achieve a compact structure by improving the utilization of both the rectifier components and the insulation distances, and consequently increase the output voltage of the power supply. The output voltages of the disks which are far away from the primary coils need to be improved to reduce their inhomogeneity. In this study, by investigating and comparing the existing compensation methods, a new combined compensation method is proposed, which increases the turns on the secondary coils and employs parallel capacitors to improve the consistency of the disks, while covering the entire operating range of the power supply. This method turns out to be both feasible and effective during the development of an ICT power supply. The non-uniformity of the output voltages of the disks is less than 3.5% from no-load to full-load, and the power supply reaches an output specification of 350 kV/60 mA.

Antimycobacterial activity of Pichia pastoris-derived mature bovine neutrophil β-defensins 5

Tuberculosis (TB) is an ongoing threat to global health, and the lack of effective therapies for treating it is also a global problem. Previous studies have shown that human cathelicidin and defensins have effective antimicrobial activity against Mycobacterium spp. To our knowledge, there are no reports on the antimycobacterial effects of bovine neutrophil β-defensins so far. Here, we identified the antimicrobial effect of mature bovine neutrophil β-defensins (mBNBD) 5 against Mycobacterium infection both in vitro and in vivo. The mBNBD5 protein was expressed in Pichia pastoris. To increase the yield of β-defensins, a purification method was employed by adding a 6-His·tag to the C-terminus of the mBNBD5 gene. Our results indicated that recombinant mBNBD5 protein was successfully expressed and purified from Pichia pastoris with intact antimicrobial activity. The recombinant protein exhibited potent bactericidal activity in vitro against M. smegmatis and M. bovis, with a dose-dependent manner and a time-dependent manner. The electron microscope results showed that the bacterial cell wall of M. bovis was disrupted when incubated with mBNBD5 for 72 h. Our data also indicated that the exogenous addition of mBNBD5 could reduce the survival of Mycobacterium spp., especially M. tuberculosis and M. bovis in RAW 264.7 macrophages. These results provide foundations for the development of mBNBD5 as a potential new therapeutic agent for TB treatment.

Multidrug-resistant genes of aminoglycoside-modifying enzymes and 16S rRNA methylases in Acinetobacter baumannii strains

We examined the distribution of genes of aminoglycoside-modifying enzymes and 16S rRNA methylases in multidrug-resistant Acinetobacter baumannii to explore the association of these genes with drug resistance. Strains isolated from clinical specimens were screened using an automatic microbial identification system, and 9 aminoglycoside-modifying enzyme and 6 16S rRNA methylase genes were analyzed using polymerase chain reaction and verified by DNA sequencing. Next, sequence alignment was carried out using the Chromas software and a susceptibility test was performed using the Kirby-Bauer disk diffusion method. Genes encoding aminoglycoside-modifying enzymes were detected in all 20 strains of multidrug-resistant A. baumannii. The positive rates of aac(3')-I, aac(6')-Ib, ant(3'')-I, and aph(3')-I were 90.0, 90.0, 85.0, and 35.0%, respectively. However, genes encoding 16S rRNA methylases were not positively detected in the 20 strains of multidrug-resistant A. baumannii. The resistance of multidrug-resistant A. baumannii may be associated with aminoglycoside-modifying enzyme genes but not with 16S rRNA methylase genes.

Associations of blood glucose and prevalent diabetes with risk of cardiovascular disease in 500 000 adult Chinese: the China Kadoorie Biobank

AIMS

To examine the relationship of self-reported diabetes, and of random blood glucose levels among individuals without known diabetes, with the prevalence of cardiovascular disease in Chinese adults.

METHODS

We examined cross-sectional data from the China Kadoorie Biobank of 0.5 million people aged 30-79 years recruited from 10 diverse regions of China in the period 2004-2008. Logistic regression was used to estimate the odds ratios of prevalent cardiovascular disease associated with self-reported diabetes, and with measured random blood glucose levels among participants with no history of diabetes, adjusting simultaneously for age, sex, area, education, smoking, alcohol, blood pressure and physical activity.

RESULTS

A total of 3.2% of participants had self-reported diabetes (men 2.9%; women 3.3%) and 2.8% had screen-detected diabetes (men 2.6%; women 2.8%), i.e. they had no self-reported history of diabetes but a blood glucose level suggestive of a diagnosis of diabetes. Compared with individuals without a history of diabetes, the odds ratios associated with self-reported diabetes were 2.18 (95% CI 2.06-2.30) and 1.88 (95% CI 1.75-2.01) for prevalent ischaemic heart disease and stroke/transient ischaemic attack, respectively. Among participants without self-reported diabetes there was a positive association between random blood glucose and ischaemic heart disease and stroke/transient ischaemic attack prevalence (P for trend <0.0001). Below the diabetic threshold (<11.1 mmol/l) each additional 1 mmol/l of random blood glucose was associated with 4% (95% CI 2-5%) and 5% (95% CI 3-7%) higher odds of prevalent ischaemic heart disease and stroke/transient ischaemic attack, respectively.

CONCLUSIONS

In this adult Chinese population, self-reported diabetes was associated with a doubling of the odds of prevalent cardiovascular disease. Below the threshold for diabetes there was still a modest, positive association between random blood glucose and prevalent cardiovascular disease.

The structure of the symptoms of major depression: exploratory and confirmatory factor analysis in depressed Han Chinese women

BACKGROUND

The symptoms of major depression (MD) are clinically diverse. Do they form coherent factors that might clarify the underlying nature of this important psychiatric syndrome?

METHOD

Symptoms at lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years with recurrent DSM-IV MD. Exploratory factor analysis (EFA) and confirmatoryfactor analysis (CFA) were performed in Mplus in random split-half samples.

RESULTS

The preliminary EFA results were consistently supported by the findings from CFA. Analyses of the nine DSM-IV MD symptomatic A criteria revealed two factors loading on: (i) general depressive symptoms; and (ii) guilt/suicidal ideation. Examining 14 disaggregated DSM-IV criteria revealed three factors reflecting: (i) weight/appetite disturbance; (ii) general depressive symptoms; and (iii) sleep disturbance. Using all symptoms (n = 27), we identified five factors that reflected: (i) weight/appetite symptoms; (ii) general retarded depressive symptoms; (iii) atypical vegetative symptoms; (iv) suicidality/hopelessness; and (v) symptoms of agitation and anxiety.

CONCLUSIONS

MD is a clinically complex syndrome with several underlying correlated symptom dimensions. In addition to a general depressive symptom factor, a complete picture must include factors reflecting typical/atypical vegetative symptoms, cognitive symptoms (hopelessness/suicidal ideation), and an agitated symptom factor characterized by anxiety, guilt, helplessness and irritability. Prior cross-cultural studies, factor analyses of MD in Western populations and empirical findings in this sample showing risk factor profiles similar to those seen in Western populations suggest that our results are likely to be broadly representative of the human depressive syndrome.

Association of the CYP1A1 MspI and TNFα-308 polymorphisms with chronic obstructive pulmonary disease in Inner Mongolia

Chronic obstructive pulmonary disease (COPD) is a progressive lung disease characterized by persistent airflow limitation. Smoking, occupational exposures, air pollution, and genetics are all risk factors. In the present study, we detected the cytochrome P4501A1 gene (CYP1A1) MspI polymorphism and the tumor necrosis factor alpha (TNFα)-308 single nucleotide polymorphism in COPD patients, and investigated their associations with smoking and COPD susceptibility in Inner Mongolia. A total of 101 COPD patients and 80 controls were enrolled in the study. The polymorphisms were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). CYP1A1 MspI allele frequencies were significantly different between COPD patients and controls (P=0.033). COPD susceptibility was higher in subjects with the m2 allele compared to subjects with the m1 allele [odds ratio (OR)=2.531, 95% confidence interval (CI)=1.297-4.940, P=0.006]. Significant differences were observed in the TNFα-308 genotype and allele distributions between COPD patients and controls (P=0.006 and P=0.003, respectively). Compared to subjects with the GG genotype, subjects with GA+AA genotypes had higher COPD risk (OR=3.639, 95%CI=1.576-8.403, P=0.002). The TNFα-308 polymorphism differed between smoking and non-smoking COPD patients and controls (P=0.047 for genotype and P=0.030 for allele). In conclusion, the CYP1A1 MspI and TNFα-308 polymorphisms were associated with COPD susceptibility. Furthermore, of the two polymorphisms, only TNFα-308 may exert an interaction with smoking.

CTC1 increases the radioresistance of human melanoma cells by inhibiting telomere shortening and apoptosis

Melanoma has traditionally been viewed as a radioresistant cancer. However, recent studies suggest that under certain clinical circumstances, radiotherapy may play a significant role in the treatment of melanoma. Previous studies have demonstrated that telomere length is a hallmark of radiosensitivity. The newly discovered mammalian CTC1-STN1-TEN1 (CST) complex has been demonstrated to be an important telomere maintenance factor. In this study, by establishing a radiosensitive/radioresistant human melanoma cell model, MDA-MB-435/MDA-MB-435R, we aimed to investigate the association of CTC1 expression with radiosensitivity in human melanoma cell lines, and to elucidate the possible underlying mechanisms. We found that CTC1 mRNA and protein levels were markedly increased in the MDA-MB-435R cells compared with the MDA-MB-435 cells. Moreover, the downregulation of CTC1 enhanced radiosensitivity, induced DNA damage and promoted telomere shortening and apoptosis in both cell lines. Taken together, our findings suggest that CTC1 increases the radioresistance of human melanoma cells by inhibiting telomere shortening and apoptosis. Thus, CTC1 may be an attractive target gene for the treatment of human melanoma.

Constructing the major biosynthesis pathways for amino acids in the brown planthopper, Nilaparvata lugens Stål (Hemiptera: Delphacidae), based on the transcriptome data

Nilaparvata lugens is a serious phloem-feeding pest of rice throughout Asia. Rice phloem sap can meet its nutrition requirement for sugars but not for some essential amino acids such as isoleucine, leucine, methionine, phenylalanine, tryptophan, lysine, arginine and histidine. N. lugens harbours yeast-like symbionts in mycetocytes formed by abdominal fat body cells. Removal of the symbionts results in negative physiological effects, suggesting that the symbionts play a pivotal role in the nitrogen metabolism. In the present paper, 521 mRNA expressed sequence tags (ESTs) encoding 126 enzymes that were involved in amino acid biosynthesis were identified based on a transcriptome data, reverse transcription (RT)-PCR and rapid amplification of cDNA ends. Similarity analysis, codon usage bias, along with tissue-biased expression and phylogenetic analysis of a subset of ESTs, suggest that 437 ESTs out of the 521 originate from symbionts, and the remaining 84 mRNA fragments come from N. lugens. Accordingly, the biosynthesis pathways for 20 amino acids were manually constructed. It is postulated that both N. lugens and its symbiont can independently assimilate ammonia and biosynthesize seven non-essential amino acids: glutamate; glutamine; aspartate; asparagine; alanine; serine; and glycine. N. lugens and symbiont enzymes may work collaboratively to catalyse the biosynthesis of proline, methionine, valine, leucine, isoleucine, phenylalanine and tyrosine. We infer from this that symbionts function in the biosynthesis of lysine, arginine, tryptophan, threonine, histidine and cysteine. Our data support the previously proposed hypothesis, i.e. the yeast-like symbionts compensate for, at least partially, the amino acid needs of N. lugens.

Myomatous hepatic angiomyolipoma: imaging findings in 14 cases with radiological-pathological correlation and review of the literature

OBJECTIVE

To display and analyse the imaging features of myomatous hepatic angiomyolipomas (MHAMLs).

METHODS

The imaging features (CT = 9; MRI = 10; ultrasound = 10; contrast-enhanced ultrasound = 4) of 14 patients with pathologically proven MHAMLs were reviewed retrospectively.

RESULTS

MHAMLs were surgically resected in the 14 patients (10 females and 4 males; age, 27-64 years; mean, 45 years), all of whom had negative hepatitis markers and were positive for the immunohistochemical stain homatropine methylbromide-45. The tumours were solitary and well defined, and ranged in size from 1.9 to 9.1 cm (mean, 5.7 cm). On dynamic contrast-enhanced CT, MRI and ultrasound scans, all tumours showed fast strong enhancement in the arterial phase and moderate washout in the portal venous and delayed phases, and the greater portions of the tumours were slightly lower than the surrounding hepatic parenchyma. In some cases, a small area of prolonged or increasing enhancement in the tumour was recognized in the delayed phase. Early draining vessels to the portal vein or hepatic vein could be seen in some cases. However, no capsular signs could be confidently identified in the delayed phase. Haemorrhagic cavities were recognized in two cases, and nodular low-intensity areas in the tumours on T2 weighted imaging that showed slow and faint enhancement on dynamic scans were seen in two cases. However, no necrosis was identified.

CONCLUSION

Dynamic enhanced imaging studies revealed some specific features of MHAMLs that distinguish them from other hypervascular hepatic tumours, especially when combined with clinical features. Familiarity with imaging and clinical features of MHAMLs could avoid unnecessary surgical resection of these generally benign tumours.

ADVANCES IN KNOWLEDGE

This article systematically describes the imaging features of MHAMLs.