Extract from Arca granosa L. Inhibits Proliferation of Human Tumour Cell Lines with Kidney and Lung Origin

Marine organisms are being considered increasingly as sources of anti-tumour agents. The extract from Arca granosa L. has been shown to decrease the growth of tumours and this study was undertaken to determine its ability and mechanism of inhibition. The extract inhibited the proliferation of six human tumour cell lines from different origins with varying sensitivity. The cell lines Ketr-3, A549 and NCI-H460 with kidney or lung origins were more sensitive to the extract than those of the HepG-2, MCF-7 and MGC-803 cells from other origins. In the three sensitive cell lines (Ketr-3, A549 and NCI-H460) the extract was shown to block different phases of the cell cycle progression and inhibit DNA synthesis in a concentration-dependent manner. It was concluded that the extract from A. granosa is potentially a novel anti-tumour agent, especially on kidney and lung tumour cell lines.

Occurrence and exposure assessment of multiple mycotoxins in dried fruits based on liquid chromatography-tandem mass spectrometry

A reliable analytical method based on liquid chromatography-tandem mass spectrometry was developed for simultaneous determination of aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1, aflatoxin G2, ochratoxin A (OTA), deoxynivalenol, T-2 and HT-2 toxin, and zearalenone (ZEA) in various dried fruits. A simple one-step sample extraction without using clean-up cartridges made the established method less labour consuming and less expensive, while optimisation of the several important MS/MS parameters, i.e. the scan time and run segments, ensured its sensitivity and selectivity. After careful validation of the method by determining the linearity (R2>0.99), recovery (77.8-115.9%), precision (relative standard deviation ≤19.5%) and sensitivity (limits of quantification in the range of 0.1-10 μg/kg), a survey of 125 dried fruit samples including 25 pistachios, 28 dried longans, 32 raisins and 40 dried dates randomly collected from different markets in Shanghai, China, was performed. Results revealed that 32.0% of samples were contaminated with different mycotoxins, among which, OTA was the most frequent contaminant with the incidence of 29.6% attaining the concentration levels in the range of 0.4-212.6 μg/kg. ZEA was positively found in 2 pistachio samples with the concentrations of 84.9 μg/kg and 426.9 μg/kg. Trace amounts of AFB1 (0.8 μg/kg) and AFB2 (0.2 μg/kg) were also observed in one pistachio sample and one dried longan sample, respectively. To the best of our knowledge, this is the first report to reveal the real situations of mycotoxin contaminations in various dried fruits in China.

HLA-B allele dropout in PCR sequence-specific oligonucleotide probe typing due to intronic polymorphism in the novel B*58:01:01:02 allele

Currently, Luminex technology based on the PCR sequence-specific oligonucleotide (SSO) probe method has been widely used for HLA genotyping in the immunogenetics laboratories. Here, we reported a case with HLA-B allele dropout by Luminex technology. The initial HLA-B result of the Luminex method with a commercial agent kit was inconclusive, and then, the result of PCR-SBT technology indicated the dropout as a HLA-B*58 allele. Subsequently, the full-length sequence of HLA-B allele was determined by TOPO-TA cloning, and a novel allele B*58:01:01:02 was identified in the individual. Compared with HLA-B*58:01:01:01, the novel allele showed some nucleotides difference at 509 C>T, 521 T>G and CCC insertion in position 503 of intron 2. According to the full-length sequence, the new mutations of intron 2 were contributed to HLA-B locus allele dropout in the sample. Our results indicated multiplatform should be used to improve the HLA typing accuracy when a conclusive HLA genotype cannot be determined.

HLA-A, -B and -DRB1 allele and haplotype frequencies of 8333 Chinese Han from the Zhejiang province, China

The distribution of human leucocyte antigen (HLA) allele and haplotype is varied among different ethnic populations. In this study, HLA-A, -B and -DRB1 allele and haplotype frequencies were determined in 8333 volunteer bone marrow donors of Zhejiang Han population using the polymerase chain reaction sequence-based typing. A total of 52 HLA-A, 96 HLA-B and 61 HLA-DRB1 alleles were found. Of these, the top three frequent alleles in HLA-A, HLA-B and HLA-DRB1 loci, respectively, were A*11:01 (24.53%), A*24:02 (17.35%), A*02:01 (11.58%); B*40:01 (15.67%), B*46:01 (11.87%), B*58:01 (9.05%); DRB1*09:01 (17.54%),DRB1*12:02 (9.64%) and DRB1*08:03 (8.65%). A total of 171 A-B-DRB1 haplotypes with a frequency of >0.1% were presented and the five most common haplotypes were A*33:03-B*58:01- DRB1*03:01, A*02:07-B*46:01-DRB1*09:01, A*30:01-B*13:02-DRB1*07:01, A*33:03-B*58:01-RB1*13:02 and A*11:01-B*15:02-DRB1*12:02. The information will be useful for selecting unrelated bone marrow donors and for anthropology studies and pharmacogenomics analysis.

Efficient oxygen electroreduction over ordered mesoporous Co–N-doped carbon derived from cobalt porphyrin

High-performance self-supported Co–N-doped carbon electrocatalyst for ORR with comparable activity to Pt/C in both acidic and alkaline media was prepared.

Hybrid graphene plasmonic waveguide modulators

The unique optical and electronic properties of graphene make possible the fabrication of novel optoelectronic devices. One of the most exciting graphene characteristics is the tunability by gating which allows one to realize active optical devices. While several types of graphene-based photonic modulators have already been demonstrated, the potential of combining the versatility of graphene with subwavelength field confinement of plasmonic waveguides remains largely unexplored. Here we report fabrication and study of hybrid graphene-plasmonic waveguide modulators. We consider several types of modulators and identify the most promising one for telecom applications. The modulator working at the telecom range is demonstrated, showing a modulation depth of >0.03 dB μm(-1) at low gating voltages for an active device area of just 10 μm(2), characteristics which are already comparable to those of silicon-based waveguide modulators while retaining the benefit of further device miniaturization. Our proof-of-concept results pave the way towards on-chip realization of efficient graphene-based active plasmonic waveguide devices for optical communications.

Establishment of Lipofection Protocol for Efficient miR-21 Transfection into Cortical Neurons In Vitro

Dysregulated microRNAs in neurons could cause many nervous system diseases. The therapeutic manipulation of these pathogenic microRNAs necessitates novel, efficient delivery systems to facilitate microRNA modulators targeting neurons with minimal off-target effects. The study aimed to establish a lipofection protocol to upregulate expression levels of miR-21 in neurons under different conditions, including different serum-free medium, transfection conditions, and reagent concentration, by evaluating the expression levels of miR-21 and neuron injury. The expression levels of miR-21 were higher in neurons transfected by Neurobasal-A than by DMEM. Expression levels of miR-21 were already the highest at the ratio RNAiMAX:miR-21 = 3:5, but the increase of RNAiMAX's concentration had not caused the further upregulation of expression level of miR-21. Neuron injury was condition dependent and dose dependent after transfection. Compared to S-Neurobasal groups, neurons have a smaller injury in N-Neurobasal groups, and compared to ratios RNAiMAX:miR-21 = 4:5, 5:5, neuron injury was smaller at ratios of RNAiMAX:miR-21 = 1:5, 2:5, 3:5. Without the pretreatment of starvation in vitro, the lipofection protocol was that RNAiMAX/miR-21 agomir complexes were diluted in Neurobasal-A at the ratio of RNAiMAX:miR-21 = 3:5.

Cervical intramedullary immature teratoma with metastatic recurrence in an adult

STUDY DESIGN

Case report.

OBJECTIVES

We present for the first time an adult patient with cervical intramedullary immature teratoma with metastatic recurrence.

SETTING

Peking university Shenzhen Hospital, Shenzhen, China.

METHODS

A 30-year-old woman presented with rapidly progressive quadriplegia. Magnetic resonance imaging (MRI) revealed an intramedullary tumor occupying C1-C2 of the upper spinal cord. An urgent operation, consisting of decompression by laminectomy and tumor gross resection, was performed under a preoperative diagnosis of spinal glioma. The histological diagnosis was immature teratoma. The patient received local radiotherapy after gross total resection. The serum alpha fetoprotein (AFP) and human chorionic gonadotropin (HCG) levels were normal postoperatively, until these were evaluated on the 10th month with neurological deterioration. Metastatic recurrences were demonstrated on MRI with lesions located at the levels of C5-C6 and T11-12. Removal of the second tumors was performed and the pathological examination identified a malignant germ cell tumor (yolk sac tumor). The patient was then referred to chemotherapy and radiotherapy.

RESULTS

No tumor regrowth was encountered and the patient remained stable for 6 months after adjuvant therapy.

CONCLUSION

Immature teratoma should be included in the differential diagnosis of holocord tumors in the adult with rapidly progressing symptoms and if found should be radically excised if possible. Adjuvant therapy should be the salvage therapy for this recurrent tumor.

Impact of Pratylenchus penetrans on Establishment of Red Raspberry

The plant-parasitic nematode, Pratylenchus penetrans, is a major constraint to red raspberry (Rubus idaeus) production. To determine the impact of P. penetrans on the establishment and productivity of eight raspberry cultivars, R. niveus, and R. leucodermis, plants were grown in fumigated and nonfumigated soil. Then, soil and root populations of P. penetrans and plant productivity (vigor, cane height, biomass, and yield) were monitored over 2 years. In a separate experiment, the role that soil type plays in mediating P. penetrans populations and raspberry establishment was investigated. At 6 and 12 months after planting, population densities of P. penetrans were lower in fumigated than in nonfumigated soil; this trend continued 18 months after planting. All cultivars and R. leucodermis were found to be extremely susceptible to damage caused by P. penetrans. By the end of the experiment, yield was the most sensitive indicator of plant productivity among cultivars, with losses in nonfumigated soil ranging from 63 to 100% of those observed in fumigated soil. However, there was no difference in the productivity of R. niveus plants grown in nonfumigated versus fumigated soils. Results also indicated that the damage potential of P. penetrans was greater on sandy loam versus silt loam soils. The total plant biomass of 'Meeker' raspberry was 46% lower in a sandy loam soil containing P. penetrans compared with soil without P. penetrans; this trend was not observed consistently in a silt loam soil. Despite the fact that soil fumigation is increasingly more limited by regulations, this study shows the utility of fumigation in reducing P. penetrans populations for a sufficient period of time to ensure that newly planted raspberry seedlings can become successfully established.

Cytochrome P450 CYP4DE1 and CYP6CW3v2 contribute to ethiprole resistance in Laodelphax striatellus (Fallén)

Laodelphax striatellus Fallén (Hemiptera: Delphacidae), a destructive pest of rice, has developed high resistance to multiple insecticides, threatening the success of pest management programmes. The present study investigated ethiprole resistance mechanisms in a field population that is highly resistant to ethiprole. That population was used to establish a laboratory population that was subjected to further selection to produce a resistant strain. Target genes were cloned and compared between the resistant and the susceptible strains, the role of detoxification enzymes was examined, and the relative expression levels of 71 detoxification enzyme genes were tested using quantitative real time (RT)-PCR. The laboratory selection enhanced the resistance from 107-fold to 180-fold. The Rdl-type target site mutation seldom occurred in the resistant strain and is unlikely to represent the major mechanism underlying the observed resistance. Of the three important detoxification enzymes, only P450 monooxygenase was found to be associated with ethiprole resistance. Moreover, two genes, CYP4DE1 and CYP6CW3v2, were found to be overexpressed in the resistant strain. Furthermore, gene-silencing via a double-stranded RNA feeding test was carried out, and the results showed that the mRNA levels of CYP4DE1 and CYP6CW3v2 were reduced in the resistant strain, whereas ethiprole susceptibility was increased. These results suggest that CYP4DE1 and CYP6CW3v2 play an important role in ethiprole resistance in L. striatellus.

Stellar dynamics. The fastest unbound star in our Galaxy ejected by a thermonuclear supernova

Hypervelocity stars (HVSs) travel with velocities so high that they exceed the escape velocity of the Galaxy. Several acceleration mechanisms have been discussed. Only one HVS (US 708, HVS 2) is a compact helium star. Here we present a spectroscopic and kinematic analysis of US 708. Traveling with a velocity of ~1200 kilometers per second, it is the fastest unbound star in our Galaxy. In reconstructing its trajectory, the Galactic center becomes very unlikely as an origin, which is hardly consistent with the most favored ejection mechanism for the other HVSs. Furthermore, we detected that US 708 is a fast rotator. According to our binary evolution model, it was spun-up by tidal interaction in a close binary and is likely to be the ejected donor remnant of a thermonuclear supernova.