Transcriptome analysis of the central nervous system of the mollusc Lymnaea stagnalis

Background

The freshwater snail Lymnaea stagnalis (L. stagnalis) has served as a successful model for studies in the field of Neuroscience. However, a serious drawback in the molecular analysis of the nervous system of L. stagnalis has been the lack of large-scale genomic or neuronal transcriptome information, thereby limiting the use of this unique model.

Results

In this study, we report 7,712 distinct EST sequences (median length: 847 nucleotides) of a normalized L. stagnalis central nervous system (CNS) cDNA library, resulting in the largest collection of L. stagnalis neuronal transcriptome data currently available. Approximately 42% of the cDNAs can be translated into more than 100 consecutive amino acids, indicating the high quality of the library. The annotated sequences contribute 12% of the predicted transcriptome size of 20,000. Surprisingly, approximately 37% of the L. stagnalis sequences only have a tBLASTx hit in the EST library of another snail species Aplysia californica (A. californica) even using a low stringency e-value cutoff at 0.01. Using the same cutoff, approximately 67% of the cDNAs have a BLAST hit in the NCBI non-redundant protein and nucleotide sequence databases (nr and nt), suggesting that one third of the sequences may be unique to L. stagnalis. Finally, using the same cutoff (0.01), more than half of the cDNA sequences (54%) do not have a hit in nematode, fruitfly or human genome data, suggesting that the L. stagnalis transcriptome is significantly different from these species as well. The cDNA sequences are enriched in the following gene ontology functional categories: protein binding, hydrolase, transferase, and catalytic enzymes.

Conclusion

This study provides novel molecular insights into the transcriptome of an important molluscan model organism. Our findings will contribute to functional analyses in neurobiology, and comparative evolutionary biology. The L. stagnalis CNS EST database is available at .

Discovery of a potent, metabolically stabilized resorcylic lactone as an anti-inflammatory lead

With bioactivity-guided phenotype screenings, a potent anti-inflammatory compound f152A1 has been isolated, characterized and identified as the known natural product LL-Z1640-2. Metabolic instability precluded its use for the study on animal disease models. Via total synthesis, a potent, metabolically stabilized analog ER-803064 has been created; addition of the (S)-Me group at C4 onto f152A1 has resulted in a dramatic improvement on its metabolic stability, while preserving the anti-inflammatory activities.

Occult hepatocellular carcinoma: a case report of a special icteric-type hepatoma and literature review

Hepatocellular carcinoma (HCC) presenting with obstructive jaundice due to bile duct tumour thrombi is classified as icteric-type hepatoma. This report describes a case of unusual icteric-type HCC with common bile duct thrombus, which is herein named 'occult HCC', as no detectable primary lesion in liver was defined pre-operatively and intra-operatively. A thrombectomy followed by a T biliary drainage tube placement was carried out, and the final post-operative pathological evaluation demonstrated the tumour thrombus originated from a moderately differentiated HCC. The clinicopathological features and logical clinical interventions of this rare type of HCC were discussed with a review of the literature. The HCC patients with bile duct thrombi receiving palliative biliary drainage alone had a poor outcome. With respect to improving prognosis, a curative resection of primary HCC and tumour thrombi was suggested on the basis of performing an intensive post-operative monitoring for early detection of primary liver lesion.

Can Magnetic Resonance Imaging Be the Key Technique to Visualize and Investigate Endovascular Biomaterials?

OBJECTIVE

Magnetic resonance imaging (MRI) is an established modality in clinical use but may be potentially underutilized to visualize and investigate biomaterials. As its use is totally contraindicated only for ferromagnetic devices, it was employed to visualize deployment, biofonctionality, healing, and biodurability of a commercially available endovascular device, namely the Medtronic-AVE AneuRx. The quality of the observations coupled with the absence of ionizing radiations are likely to make this technique an attractive imaging modality in the future.

METHOD

The potential benefits of the MRI technique were investigated in a GE Vectra-MR 0.5T MRI for the Medtronic-AVE AneuRx endovascular prosthesis, under different conditions: undeployed i.e., inserted in the delivery cartridge as received from the manufacturer (step 1), deployed in a mock glass-aneurysm tube (step 2), and as a pathological explant harvested at the autopsy of a patient (step 3). The device was submitted to X-rays for examination in addition to MRI. At step 3, the device was further investigated with light microscopy and scanning electron microscopy (SEM) together with X-ray diffraction.

RESULTS

The device which was inserted and pleated in the delivery cartridge did not demonstrate any significant observation either in MRI or in X-rays. When it was deployed in the mock aneurysmal glass tube, light artefacts were associated with the T2 weighed FSE images around the Nitinol whereas X-rays gave images of indisputable interest. Similar results were noted using the explanted device. Very high contrasts were obtained with T1 whereas T2 images were almost defect free. The X-rays allowed to accurate imaging of the Nitinol skeleton but were poor to discriminate between the different tissues. Pathology observations using light microscopy were not really challenged, as the magnetic resonance imaging was performed using a 0.5T machine.

DISCUSSION

The benefits of magnetic resonance imaging as a quality control technique to examine an endovascular device within its cartridge remains ill defined. Similarly, the role of conventional X-rays is unknown. The observation of devices fully deployed in a mock aneurysmal glass-tube under MRI are potentially useful but X-rays images allowed better definition. The MRI examination of the explanted device does permit observations related to the healing of the device that might be obtained in vivo and, thus offers new avenues for the follow-up of implanted devices. The pathological investigations brought additional informations about the tissues and the corrosion of the Nitinol. However, it is unlikely that MRI will permit detailed analysis of the biomaterials and in particular the corrosion process of the stents.

CONCLUSION

These early observations of the follow-up of devices using MRI warrant further investigation. The absence of ionizing radiation with MRI makes this technique particularly attractive. As there is no emission of ionizing radiation associated with magnetic resonance, it is recommended that further investigation using this environment friendly technique for the follow-up of devices made of biomaterials that are MRI compatible.

Combination of beta-TCP and BMP-2 gene-modified bMSCs to heal critical size mandibular defects in rats

OBJECTIVE

To investigate the effects of mandibular defects repaired by a tissue engineered bone complex with beta-tricalcium phosphate (beta-TCP) and bone morphogenic protein-2 (BMP-2) gene-modified bone marrow stromal cells (bMSCs).

MATERIALS AND METHODS

bMSCs derived from Fisher 344 rats were cultured and transduced with adenovirus AdBMP-2, AdEGFP gene in vitro. Osteogenic differentiation of bMSCs was determined by alkaline phosphatase staining, von Kossa assay and reverse transcription-polymerase chain reaction. Gene transduced or untransduced bMSCs were seeded on beta-TCP scaffolds to repair mandibular full thickness defects with a diameter of 5 mm. Eight weeks post-operation, X-ray examination, micro-computerized tomography and histological and histomorphological analysis were used to evaluate the bone healing effects.

RESULTS

Alkaline phosphatase staining and mineralized nodules formation were more pronounced in AdBMP-2 group 14 days after gene transduction when compared with that of AdEGFP or untransduced group. The mRNA expression of osteopontin and osteocalcin also significantly increased 9 days after AdBMP-2 gene transduction. Mandibular defects were successfully repaired with AdBMP-2-transduced bMSCs/beta-TCP constructs. The percentage of new bone formation in AdBMP-2 group was significantly higher than that of other control groups.

CONCLUSIONS

Bone morphogenic protein-2 regional gene therapy together with beta-TCP scaffold could be used to promote mandibular repairing and bone regeneration.

Variants in KCNQ1 are associated with susceptibility to type 2 diabetes in the population of mainland China

AIMS/HYPOTHESIS

Two recent genome-wide association studies have identified several novel type 2 diabetes susceptibility variants in intron 15 of the KCNQ1 gene. We aimed to evaluate the effects of the variants in KCNQ1 on type 2 diabetes and metabolic traits in the population of mainland China.

METHODS

Three candidate single nucleotide polymorphisms were genotyped in 1,912 individuals with type 2 diabetes and 2,041 normal controls using the ligase detection reaction method.

RESULTS

We confirmed the association of KCNQ1 with type 2 diabetes in the population of mainland China. Allele frequency ORs of the three single nucleotide polymorphisms (SNPs) were: rs2237892 (OR 1.19, 95% CI 1.08-1.31, p = 3.0 x 10(-4)); rs2237895 (OR 1.20, 95% CI 1.09-1.32, p = 1.9 x 10(-4)); and rs2237897 (OR 1.24, 95% CI 1.13-1.36, p = 3.9 x 10(-5)). We also found a significant difference in the distribution of the global haplotypes between the type 2 diabetes group and the normal control group (p = 2.6 x 10(-5)). In addition, in the control group SNP rs2237892 was marginally associated with increasing fasting plasma glucose and SNPs rs2237892 and rs2237897 were associated with HbA(1c). Furthermore, for all three variants, homozygous carriers of the diabetes-associated allele had significantly decreased BMI and waist circumferences.

CONCLUSIONS/INTERPRETATION

Our investigation confirmed the effects of KCNQ1 variants on type 2 diabetes risk in the Chinese population.

The Archaeotools project: faceted classification and natural language processing in an archaeological context

This paper describes 'Archaeotools', a major e-Science project in archaeology. The aim of the project is to use faceted classification and natural language processing to create an advanced infrastructure for archaeological research. The project aims to integrate over 1 x 10(6) structured database records referring to archaeological sites and monuments in the UK, with information extracted from semi-structured grey literature reports, and unstructured antiquarian journal accounts, in a single faceted browser interface. The project has illuminated the variable level of vocabulary control and standardization that currently exists within national and local monument inventories. Nonetheless, it has demonstrated that the relatively well-defined ontologies and thesauri that exist in archaeology mean that a high level of success can be achieved using information extraction techniques. This has great potential for unlocking and making accessible the information held in grey literature and antiquarian accounts, and has lessons for allied disciplines.

Distribution of phthalate esters in soil of e-waste recycling sites from Taizhou city in China

In recent years, increasing concern has surrounded the consequences of improper electric and electronic waste (e-waste) disposal. In this paper, Phthalate esters (PAEs) including dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), Di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP) in the e-waste soils were collected and analyzed from sites Fengjiang, Nanshan and Meishu in Taizhou city. The result showed that the total PAEs concentrations ranged from 12.566 to 46.669 mg/kg in these three sites. DEHP, DBP and DEP were the major phthalates accounting for more than 94% of total phthalates studied. Comparing to the results from other studies, the e-waste soils from Taizhou city were severely contaminated with PAEs.

Altered mechanosensitive properties of vagal afferent fibers innervating the stomach following gastric surgery in rats

BACKGROUND AND AIMS

Several types of gastric surgeries have been associated with early satiety, dyspepsia and food intolerances. We aimed to examine alterations in gastric vagal afferents following gastric surgery-fundus ligation.

METHODS

Six week old, male Sprague-Dawley rats underwent chronic ligation (CL) of the fundus. Sham rats underwent abdominal surgery, but without ligation. Another group of rats underwent acute ligation (AL) of the fundus immediately prior to experiments. CL and sham rats were allowed to grow to age 3-4 months. Food intake and weights were recorded post-operatively. Gastric compliance and gastric wall thickness was measured at baseline and during gastric distension (GD). Extracellular recordings were made to examine response characteristics of vagal afferent fibers to GD and to map the stomach receptive field (RF). The morphological structures of afferent terminals in the stomach were examined with retrograde tracings from the nodose ganglion.

RESULTS

The CL group consumed significantly less food and weighed less than sham control. The mean compliance of the CL group was significantly less than control, but higher than the AL group. The spontaneous firing and responses to GD of afferent fibers from the CL rats were significantly higher than AL rats. There was a marked expansion of the gastric RF in the CL rats with significant reorganization and regeneration of intramuscular array (IMA) terminals. There was no difference in total wall or muscle thickness among the groups.

CONCLUSION

CL results in aberrant remodeling of IMAs with expansion of the gastric RF and alters the mechanotransduction properties of vagal afferent fibers. These changes could contribute to altered sensitivity following gastric surgery.

A phase I study assessing the feasibility and safety of intraductal pegylated liposomal doxorubicin (PLD) in women with breast cancer

e11506

Background: Most breast cancers originate in epithelial cells lining the breast ducts. Preclinical data suggest that intraductal administration of chemotherapy including PLD decrease tumor volume, prevent the development of new lesions, and eradicate pre-malignant disease. We initiated a clinical trial to determine the feasibility, safety, and maximum tolerated dose of PLD administered into one duct of women awaiting mastectomy. Methods: Women 18 or older awaiting mastectomy for breast cancer were eligible. Preoperative chemotherapy was allowed. T4 tumors, prior breast irradiation, or surgeries that may have altered the ductal system were excluded. Nipple aspiration and ductal cannulation were completed and the first 3 women received 5 mL of intraductal dextrose. PLD was administered to subsequent participants on a dose escalation schema based on preclinical pharmacokinetic and safety data. Serial doxorubicin (Dox) and doxorubicinol (Doxol) concentrations were determined in plasma by LC/MS/MS. At mastectomy (completed at least 2 weeks after intraductal administration of PLD), blue dye was injected into the treated duct and tissue was obtained for pharmacokinetic and biomarker analysis. Results: From 2/06 to 6/08, 14 women enrolled, and 12 underwent all study procedures. All dose levels up to 10 mg PLD per one duct were completed without serious adverse events. Median pain score was 0.9 (0–2.3). Intraductal PLD resulted in a dose-dependent increase in both systemic and local exposure to dox and doxol. Neither dox nor the metabolite was detected in the contralateral breast. Systemic exposure was lower than with conventionally administered PLD. Inflammatory changes were not observed on histopathological review of mastectomy specimens. Conclusions: We have established the logistics of intraductal administration of agents in an outpatient setting and it is feasible in women with and without prior chemotherapy. Biomarker data will be completed prior to the meeting. Future studies will evaluate other agents administered to one or more ducts.

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