Dopaminergic and behavioural changes in a loss-of-imprinting model of Cdkn1c

The imprinted gene Cdkn1c is expressed exclusively from the maternally inherited allele as a consequences of epigenetic regulation. Cdkn1c exemplifies many of the functional characteristics of imprinted genes, playing a role in foetal growth and placental development. However, Cdkn1c also plays an important role in the brain, being key to the appropriate proliferation and differentiation of midbrain dopaminergic neurons. Using a transgenic model (Cdkn1c^BACx1) with a twofold elevation in Cdkn1c expression that mimics loss‐of‐imprinting, we show that increased expression of Cdkn1c in the brain gives rise to neurobiological and behavioural changes indicative of a functionally altered dopaminergic system. Cdkn1c^BACX1 mice displayed altered expression of dopamine system‐related genes, increased tyrosine hydroxylase (Th) staining and increased tissue content of dopamine in the striatum. In addition, Cdkn1c^BACx1 animals were hypersensitive to amphetamine as showed by c‐fos expression in the nucleus accumbens. Cdkn1c^BACX1 mice had significant changes in behaviours that are dependent on the mesolimbic dopaminergic system. Specifically, increased motivation for palatable food stuffs, as indexed on a progressive ratio task. In addition, Cdkn1c^BACX1 mice displayed enhanced social dominance. These data show, for the first time, the consequence of elevated Cdkn1c expression on dopamine‐related behaviours highlighting the importance of correct dosage of this imprinted gene in the brain. This work has significant relevance for deepening our understanding of the epigenetic factors that can shape neurobiology and behaviour.

Surface-dominated conduction up to 240 K in the Kondo insulator SmB6 under strain

SmB₆ is a strongly correlated mixed-valence Kondo insulator with a newly discovered surface state, proposed to be of non-trivial topological origin. However, the surface state dominates electrical conduction only below T^∗ ≈ 4 K (ref. ), limiting its scientific investigation and device application. Here, we report the enhancement of T^∗ in SmB₆ under the application of tensile strain. With 0.7% tensile strain we report surface-dominated conduction at up to a temperature of 240 K, persisting even after the strain has been removed. This can be explained in the framework of strain-tuned temporal and spatial fluctuations of f-electron configurations, which might be generally applied to other mixed-valence materials. We note that this amount of strain can be induced in epitaxial SmB₆ films via substrate in potential device applications.

Transplantation of Adipose-Derived Mesenchymal Stem Cells Efficiently Rescues Thioacetamide-Induced Acute Liver Failure in Mice

BACKGROUND

We aimed to investigate the efficacy of adipose-derived mesenchymal stem cell (ADMSC) transplantation in acute liver failure caused by thioacetamide in mice as well as its underlying mechanism by comparing transplantation routes.

METHODS

ADMSCs were isolated from inguinal fat pads of enhanced green fluorescent protein (EGFP) transgenic mice and analyzed regarding their surface markers and differentiation potential. Acute liver failure models were established by infusion of thioacetamide, and then we injected EGFP-ADMSCs or phosphate-buffered saline solution by intrasplenic or intravenous route. The restoration of biologic functions of the livers receiving transplantation was assessed by means of a variety of approaches, such as survival rates, live function parameters, histology, localization of EGFP-ADMSCs, and immunofluorescence analysis.

RESULTS

ADMSCs were positive for CD90 and CD44 and negative for CD34 and had adipogenic and osteogenic differentiation potential. And they prevented the release of liver injury biomarkers. Transplantation via tail vein provided a significant survival benefit, but no significant differences were observed in the intrasplenic pathway and between the 2 pathways in our animal experiments. Furthermore, the transplanted cells were well integrated into injured livers and produced albumin and cytokeratin-8.

CONCLUSIONS

Direct transplantation of ADMSCs is an effective treatment for acute liver failure rather than intrasplenic transplantation. The transplanted ADMSCs exhibit the potential to differentiate into hepatocyte-like cells in the injured livers. Thus, ADCMSCs would be a potential option for treatment of acute liver failure.

Presynaptic PICK1 facilitates trafficking of AMPA-receptors between active zone and synaptic vesicle pool

Previous studies have indicated that presynaptic α-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptors (AMPARs) contribute to the regulation of neurotransmitter release. In hippocampal synapses, the presynaptic surface expression of several AMPAR subunits, including GluA2, is regulated in a ligand-dependent manner. However, the molecular mechanisms underlying the presynaptic trafficking of AMPARs are still unknown. Here, using bright-field immunocytochemistry, western blots, and quantitative immunogold electron microscopy of the hippocampal CA1 area from intact adult rat brain, we demonstrate the association of AMPA receptors with the presynaptic active zone and with small presynaptic vesicles, in Schaffer collateral synapses in CA1 of the hippocampus. Furthermore, we show that GluA2 and protein interacting with C kinase 1 (PICK1) are colocalized at presynaptic vesicles. Similar to postsynaptic mechanisms, overexpression of either PICK1 or pep2m, which inhibit the N-ethylmaleimide sensitive fusion protein (NSF)-GluA2 interaction, decreases the concentration of GluA2 in the presynaptic active zone membrane. These data suggest that the interacting proteins PICK1 and NSF act as regulators of presynaptic GluA2-containing AMPAR trafficking between the active zone and a vesicle pool that may provide the basis of presynaptic components of synaptic plasticity.

Qualitative and quantitative determination of coumarin using surface-enhanced Raman spectroscopy coupled with intelligent multivariate analysis

Coumarin is harmful to health but still used in cosmetics, tobacco, or illegally added into food as a spice in trace amounts so that it is exceedingly difficult to be determined accurately.

Transcript analysis in two alfalfa salt tolerance selected breeding populations relative to a non-tolerant population

With the growing limitations on arable land, alfalfa (a widely cultivated, low-input forage) is now being selected to extend cultivation into saline lands for low-cost biofeedstock purposes. Here, minerals and transcriptome profiles were compared between two new salinity-tolerant North American alfalfa breeding populations and a more salinity-sensitive western Canadian alfalfa population grown under hydroponic saline conditions. All three populations accumulated two-fold higher sodium in roots than shoots as a function of increased electrical conductivity. At least 50% of differentially expressed genes (p < 0.05) were down-regulated in the salt-sensitive population growing under high salinity, while expression remained unchanged in the saline-tolerant populations. In particular, most reduction in transcript levels in the salt-sensitive population was observed in genes specifying cell wall structural components, lipids, secondary metabolism, auxin and ethylene hormones, development, transport, signalling, heat shock, proteolysis, pathogenesis-response, abiotic stress, RNA processing, and protein metabolism. Transcript diversity for transcription factors, protein modification, and protein degradation genes was also more strongly affected in salt-tolerant CW064027 than in salt-tolerant Bridgeview and salt-sensitive Rangelander, while both saline-tolerant populations showed more substantial up-regulation in redox-related genes and B-ZIP transcripts. The report highlights the first use of bulked genotypes as replicated samples to compare the transcriptomes of obligate out-cross breeding populations in alfalfa.

[Extended inferior meatal approach by reversing inferior turbinate for maxillary sinus and adjacent lesions]

Objective:The aim of this study is to explore the feasibility and results of surgical removal of maxillary sinus and adjacent lesions via extended inferior meatal approach by reversing inferior turbinate.Method:Among these 28 cases,there were 9 cases of maxillary cysts(4 of which with oroantral fistula),2 cases of odontogenic maxillary sinusitis(1 of which with oroantral fistula),3 cases of maxillary sinus cysts,2 cases of antrochoanal polyps,5 cases of maxillary sinus inverted papilloma,1 case of maxillary sinus inverted papilloma with infiltrative squamous cell carcinoma(moderately differentiated),4 cases of inferior orbital fracture,1 case of anterior maxillary sinus wall fracture,and 1 case of infratemporal fossa cysts with fungal maxillary sinusitis.All operations were conducted via extended inferior meatal approach.Result:All patients did not have intraoperative complications,and were free of recurrence after the 3 to 36 months postoperative follow-up.Conclusion:The extended inferior meatal approach by reversing inferior turbinate can deal with all aspects of the maxillary sinus and retromaxillary lesions.This procedure has a clear vision and high successful rate.

Effect of MSTN propeptide protein on the growth and development of Altay lamb muscle

Prokaryotic expression technology was used to express maltose-binding protein binding myostatin (MSTN) propeptide fusion protein. Six disease-free Altay lambs were used in this study. The right leg gastrocnemii were injected with MSTN recombinant propeptide protein. The left leg gastrocnemii (the control group) were injected with the same dose of phosphate based saline. The lambs were fed during four months under the same conditions and then slaughtered. Gastrocnemius samples were hematoxylin-eosin stained and the size of the muscle fibers was measured. A real-time polymerase chain reaction (RT-PCR) showed that single gastrocnemius cells in the experimental group had an average area of 1163.01 µm(2), while it was 845.09 µm(2) in the control group (P < 0.05). This indicates that the MSTN propeptide biological agents had an inhibitory effect on MSTN. In order to reveal its mechanism, RT-PCR was conducted to detect the expression of the differentiation-associated genes MyoD, Myf5, Myogenin, p21, and Smad3. The results showed that, in the MSTN propeptide biological agent injected group, expression levels of MSTN, Smad3, and p21 were lower than the control group, while Myf5, MyoD, and Myogenin were higher compared to the control group. This indicates that, when expression of the MSTN gene was inhibited, muscle cell differentiation and growth can be promoted by Smad3 up-regulated expression of Myf5, MyoD, and Myogenin.

Cloning and expression of the 4D8 gene from Hyalomma asiaticum tick

Hyalomma asiaticum tick, an important ectozoic parasite causes tickle, pain, anemia, weight loss, and paralysis in its hosts, which include humans, cattle, sheep, horses, camels, and hares. The 4D8 gene can be a potential vaccine candidate antigen for H. asiaticum. In the present study, we cloned and expressed the 4D8 gene of H. asiaticum from Xinjiang Province. Primers were designed according to the H. asiaticum tick 4D8 gene sequence available in GenBank. The gene was amplified by reverse transcription-polymerase chain reaction and the fragments were subcloned into the prokaryotic expression vector pET30a and the recombinant vector pET30a-4D8 was constructed. The expressed recombinant protein was purified and its biological activity was investigated by western blot. Results revealed that the recombinant protein was a biologically active fusion protein with a molecular weight of 20 kDa. The purified 4D8 protein would provide a strong foundation for further studies on this protein.

Sequence analysis of peste des petits ruminants virus from ibexes in Xinjiang, China

Peste des petits ruminants (PPR) is an infectious disease caused by peste des petits ruminants virus (PPRV). While PPR mainly affects domestic goats and sheep, it also affects wild ungulates such as ibex, blue sheep, and gazelle, although there are few reports regarding PPRV infection in wild animals. Between January 2015 and February 2015, it was found for the first time that wild ibexes died from PPRV infection in Bazhou, Xinjiang, China, where a total of 38 ibexes (including young and adult ibexes) were found to have died abnormally from PPR-related issues. First, we tested for the presence of the F gene of PPRV by RT-PCR. Then, we compared the sequence of the isolated F gene from the ibex strain, termed PPRV Xinjiang/Ibex/2015, with those previously identified from small domestic ruminants from local areas near where the reported isolate was collected as well as those from other regions. The current sequence was phylogenetically classified as a lineage IV virus, and shared a high level of sequence identity (99.7%) with a previously described Xinjiang PPRV isolate.

Expression of recombinant myostatin propeptide pPIC9K-Msp plasmid in Pichia pastoris

Myostatin propeptide can inhibit the biological activity of myostatin protein and promote muscle growth. To express myostatin propeptide in vitro with a higher biological activity, we performed codon optimization on the sheep myostatin propeptide gene sequence, and mutated aspartic acid-76 to alanine based on the codon usage bias of Pichia pastoris and the enhanced biological activity of myostatin propeptide mutant. Modified myostatin propeptide gene was cloned into the pPIC9K plasmid to form the recombinant plasmid pPIC9K-Msp. Recombinant plasmid pPIC9K-Msp was transformed into Pichia pastoris GS115 by electrotransformation. Transformed cells were screened, and methanol was used to induce expression. SDS-PAGE and western blotting were used to verify the successful expression of myostatin propeptide with biological activity in Pichia pastoris, providing the basis for characterization of this protein.

Experimental infection of pregnant rabbits with hepatitis E virus demonstrating high mortality and vertical transmission

A high mortality rate of approximately 20% in pregnant women with hepatitis E has been reported in previous studies. However, other studies showed no difference between pregnant and nonpregnant women in the severity of hepatitis E. To determine the effects of HEV infection on pregnancy, we successfully established HEV infection in six pregnant rabbits (PR) and six nonpregnant rabbits (NPR) with a rabbit HEV isolate, taking three PR and one NPR without HEV infection as controls. Tests for HEV RNA by RT-PCR, anti-HEV antibodies by ELISA and HEV antigen via immunohistochemistry and histopathology were carried out. Two of six infected PR miscarried and three of the remaining four PR died which may be attributed to severe liver necrosis caused by HEV infection. Moreover, vertical transmission was found to be associated with the replication of HEV in placenta, indicated by the presence of HEV RNA and antigen in placenta from the infected PR. Our findings strongly suggest that HEV infection could lead to adverse outcomes in pregnancy and vertical transmission, suggesting the necessity for pregnant women at risk of HEV infection to be vaccinated.

Diabetes mellitus is associated with breast cancer: systematic review, meta-analysis, and in silico reproduction

AIM

Breast cancer (BrCa) and diabetes mellitus (DM) are two major heath problems in women and the general population. This study explores the association between DM and breast cancer patients' survival outcomes, as well as the potential therapeutic merits of metformin.

METHODS

To explore the association between DM and BrCa, we performed systematic literature search in EMBASE (www.embase.com) and MEDLINE (www.ncbi.nlm.nih.gov/pubmed) from January 1960 to April 2014 and systematically identified clinical studies that assessed the association between BrCa mortality and DM. The NCBI Gene Expression Omnibus (GEO) database was analyzed to identify micro-RNA change in BrCa cells treated by metformin, a common drug for DM worldwide.

RESULTS

Twenty studies were selected for the meta-analysis, of which 16 reported all-cause mortality and 12 reported cancer specific death. During our inclusion period, the cohorts encompassed a total of 2,645,249 patients including more than 207,832 DM patients. Pre-existing DM was associated with a 37% increase of all-cause mortality risk for women with BrCa (HR=1.37; 95%CI: 1.34-1.41; P=0.02). DM was in general associated with a 17% increased risk for BrCa mortality in women (HR=1.17; 95%CI: 1.11-1.22; P<0.01). The GEO analysis revealed downregulation of a series of pro-tumorigenic micro-RNAs following metformin treatment, which was in part restored by DICER knockdown.

CONCLUSION

Women with DM are at higher risk of BrCa-specific and all-cause mortality after initial breast cancer diagnosis. BrCa patients with DM could possibly benefit from metformin treatment via DICER mediation.

miR-199a impairs autophagy and induces cardiac hypertrophy through mTOR activation

Basal autophagy is tightly regulated by transcriptional and epigenetic factors to maintain cellular homeostasis. Dysregulation of cardiac autophagy is associated with heart diseases, including cardiac hypertrophy, but the mechanism governing cardiac autophagy is rarely identified. To analyze the in vivo function of miR-199a in cardiac autophagy and cardiac hypertrophy, we generated cardiac-specific miR-199a transgenic mice and showed that overexpression of miR-199a was sufficient to inhibit cardiomyocyte autophagy and induce cardiac hypertrophy in vivo. miR-199a impaired cardiomyocyte autophagy in a cell-autonomous manner by targeting glycogen synthase kinase 3β (GSK3β)/mammalian target of rapamycin (mTOR) complex signaling. Overexpression of autophagy related gene 5 (Atg5) attenuated the hypertrophic effects of miR-199a overexpression on cardiomyocytes, and activation of autophagy using rapamycin was sufficient to restore cardiac autophagy and decrease cardiac hypertrophy in miR-199a transgenic mice. These results reveal a novel role of miR-199a as a key regulator of cardiac autophagy, suggesting that targeting miRNAs controlling autophagy as a potential therapeutic strategy for cardiac disease.