The comparison of changes in behavior, neurochemistry, endocrine, and immune functions after different routes, doses and durations of administrations of IL-1beta in rats

BACKGROUND

Increased interleukin-1beta (IL-1) in the brain and periphery has been associated with neurodegenerative and psychiatric disorders. However, results from different IL-1 sources, administrating routes, doses and treatment duration were inconsistent and confused. The neuroendocrine-immune mechanism by which IL-1-induced behavioral changes occur is still unclear.

METHODS

In the present study, the acute and sub-chronic effects of rat recombinant IL-1, following either intraperitoneal (ip) or intracerebroventricular (icv) injection, were studied on the behavior, corticosterone secretion, peripheral inflammatory responses and brain monoamines.

RESULTS

In the open field apparatus, IL-1 (ip) increased locomotor activity but decreased the activity following icv administration. IL-1 had a greater anxiogenic effect in the elevated plus maze after icv than after ip administration. In the Morris water maze spatial memory was only impaired following sub-chronic and icv administration. Both acute and sub-chronic IL-1 increased the serum corticosterone concentration and decreased the release of the anti-inflammatory cytokine IL-10 from whole blood cultures. However, centrally administered IL-1 increased, while peripherally administered decreased, the release of PGE2 from blood cultures. After sub-chronic administration, the noradrenaline concentration was decreased in several limbic regions, while the turnovers of serotonin and dopamine were increased.

DISCUSSION

These results suggest that 1) IL-1 effects depended on the dose, route and duration of administration, and 2) IL-1 enhances the responsiveness of rats to stressful environmental stimuli. In addition, the sub-chronic administration of IL-1 induces behavioral, neurotransmitter, hormonal and immune changes that may be causally implicated in the mechanism of some of psychiatric disorders such as depression.

Localized adenovirus gene delivery using antiviral IgG complexation

Gene therapy with viral vectors has progressed to clinical trials. However, the localization of viral vector delivery to diseased target sites remains a challenge. We tested the hypothesis that an adenoviral vector could be successfully delivered by complexation with a specific antibody that is bound to a biodegradable matrix designed for achieving localized gene transduction. We report the first successful delivery system based upon antibody immobilization of virions in a type I collagen-avidin gel using a polyclonal biotinylated IgG specific for the adenovirus hexon. In vitro stability studies demonstrated retention of viral vector activity with antibody-complexed adenovirus collagen gel preparations, in comparison to loss of vector activity from collagen gels prepared with nonspecific biotinylated IgG. Cell culture investigations using this antibody-controlled release system for adenoviral vector transduction of rat aortic smooth muscle cells (A10) demonstrated a significantly more localized reporter expression (beta-galactosidase) compared with non-antibody-complexed controls. Herpes simplex thymidine kinase (HSVtk) adenoviral vectors were immobilized on avidin-collagen gels via this antibody-complexation approach, and ganciclovir was added to rat smooth muscle cells (A10) in culture with the gels. With complexed HSVtk adenovirus, only cells either in contact with the virus-containing gel or within 50 microm were killed. By comparison, at the same adenovirus and ganciclovir dose, non-antibody-complexed HSVtk adenoviral delivery with ganciclovir resulted in the death of virtually all cells. Myocardial gene transfer studies in pigs demonstrated significantly more efficient right ventricular adenoviral GFP expression with anti-hexon antibody-complexed matrix injections, compared with direct vector injections. Thus, our results show that matrix formulations based on antibody-complexation delivery of adenovirus resulted in site-specific localization of transgene expression that enhances the efficiency of therapeutic vector strategies and provides a potent means for localization, to avoid distal side-effects. This approach has therapeutic potential as an implantable preparation that through the means of antibody-complexation, can localize and optimize viral vector gene therapy.

In vitro immunoregulatory effects of lithium in healthy volunteers

RATIONALE

There is now some evidence that major depression is associated with activation of the inflammatory response system (IRS). Lithium is effective in the treatment and prophylaxis of major depression and shows significant immunoregulatory functions.

OBJECTIVE

The aims of the present study were to examine the in vitro effects of lithium on the unstimulated and lipolysaccharide (LPS) + phytohemagglutinin (PHA)-induced production of proinflammatory cytokines, such as interleukin-6 (IL-6), IL-8, tumor necrosis factor-alpha (TNFalpha) and interferon-gamma (IFNgamma), and negative immunoregulatory cytokines or proteins, such as IL-10 and the IL-1 receptor antagonist (IL-1RA).

METHODS

The in vitro effects of lithium carbonate at low (10(-4) M and 10(-5) M) and therapeutic (10(-3) M) concentrations on the above cytokines and the IL-1RA were examined in nine healthy volunteers on whole blood supernatant cultured for 72 h.

RESULTS

Lithium (10(-3) M) in the presence of LPS+PHA significantly increased the stimulated production of IFNgamma, IL-8, TNFalpha, IL-1RA and IL-10. Lithium (10(-3) M) significantly increased the unstimulated production of IL-8 and IL-10.

CONCLUSIONS

The results suggest that lithium has significant immunoregulatory effects by increasing the production of both proinflammatory cytokines (IFNgamma, TNFalpha and IL-8) and negative immunoregulatory cytokines or proteins (IL-10 and the IL-1RA).

Behavioral, neurochemical, and immunological responses to CRF administration. Is CRF a mediator of stress?

The effect of subacute intracerebroventricular (icv 0.1, 0.5, and 1.0 microgram) administration of corticotropin-releasing factor (CRF) for 5 days on behavior, neurotransmitter concentrations, and immune functions was studied in rats. The results showed that CRF administration produced a dose-dependent increase in locomotor activity in the "open field" test compared with controls; rearing scores were also significantly increased. In the elevated plus maze apparatus, rats given 1.0 microgram CRF spent considerably less time on the open arms when compared with controls. Following 0.5 and 1.0 microgram of CRF infusion, the concentrations of noradrenaline (NA), dopamine (DA) and 5-hydroxy indole acetic acid (5-HIAA) were significantly increased in the hypothalamus. There was no significant change in the concentrations of neurotransmitters in the other brain regions. CRF administration also produced a dose-dependent increase in the levels of corticosterone in the serum. The immunological results clearly showed that subacute icv CRF administration caused a reduction of lymphocyte proliferation, a decrease in the percentage of lymphocytes, and an increase in neutrophil percentage in the differential white blood cell (WBC) count, a decrease in neutrophil phagocytosis, and elevated leucocyte adhesiveness/aggregation (LAA) compared with control animals. These results suggest that icv subacute administration of CRF has anxiogenic effects, increases biogenic amine concentrations in the hypothalamus, and changes in some aspects of immune functions that may reflect the stress-inducing properties of the peptide. These effects are time and dose dependent.

Rat brain cannabinoid receptors are N-linked glycosylated proteins

To study the N-linked glycosylation properties of the CB1 receptor, rat brain membranes were treated with exo- and endoglycosidases. For visualizing CB1 receptors, an antipeptide antibody was raised against the N-terminal 14 amino acids and used to specifically detect the protein by Western blotting. We found that the apparent molecular weight of mature CB1 receptors was 64 kDa. Treatment of membranes with endoglycosidase F shifted the 64 kDa band to the 59 kDa and 53 kDa bands. The latter is consistent with the calculated molecular weight of deglycosylated CB1 receptors. Treatment of membranes with endoglycosidase H and alpha-mannosidase partially shifted the 64 kDa band to 53 kDa band, indicating a portion of the oligosaccharides was of the high mannose type. These data confirmed that the CB1 receptors in brain are N-linked glycoproteins with heterogeneous carbohydrate composition. Among three potential N-linked glycosylation sites on the N-terminus of the CB1 receptor, only two sites are actually glycosylated.

Room-temperature perpendicular exchange coupling and tunneling anisotropic magnetoresistance in an antiferromagnet-based tunnel junction

We investigate the exchange coupling between perpendicular anisotropy (PMA) Co/Pt and IrMn in-plane antiferromagnets (AFMs), as well as tunneling anisotropic magnetoresistance (TAMR) in [Pt/Co]/IrMn/AlO_{x}/Pt tunnel junctions, where Co/Pt magnetization drives rotation of AFM moments with the formation of exchange-spring twisting. When coupled with a PMA ferromagnet, the AFM moments partially rotate with out-of-plane magnetic fields, in contrast with being pinned along the easy direction of IrMn for in-plane fields. Because of the superior thermal tolerance of perpendicular exchange coupling and the stability of moments in ~6 nm-thick IrMn, TAMR gets significantly enhanced up to room temperature. Their use would advance the process towards practical AFM spintronics.

Influence of psychological stress on immune-inflammatory variables in normal humans. Part II. Altered serum concentrations of natural anti-inflammatory agents and soluble membrane antigens of monocytes and T lymphocytes

The effects of academic examination stress on serum concentrations of interleukin (IL)-1 receptor (R) antagonist (A), soluble(s) IL-2R, sIL-6R, soluble glycoprotein 130 (sgp130), Clara cell protein (CC16), sCD8 and sCD14 were evaluated in 38 university students. The relationships among changes in the above immune-inflammatory variables, levels of serum cortisol, and scores on the Perceived Stress Scale (PSS) or the State-Trait Anxiety Inventory (STAI) were examined. Academic examination stress was associated with significant increases in PSS and STAI scores, and in serum sgp130 and sCD8 values. Academic examination stress was associated with significantly decreased serum sCD14 concentrations in students with high, but not low, stress perception. There were stress-induced differences in serum IL-1RA, sIL-6R and CC16 concentrations between students with high vs. low stress-induced anxiety. The stress-induced increase in serum sCD8 was significantly more pronounced in male students, whereas the increase in serum sgp130 was more pronounced in female students taking contraceptive drugs. These results suggest that: (1) psychological stress induces immune-inflammatory changes pointing toward complex regulatory responses in IL-6 signalling, a decreased anti-inflammatory capacity of the serum, and interactions with T cell and monocytic activation; and that (2) sex hormones may modify stress-induced immune-inflammatory responses.

Coherent population transfer between uncoupled or weakly coupled states in ladder-type superconducting qutrits

Stimulated Raman adiabatic passage offers significant advantages for coherent population transfer between uncoupled or weakly coupled states and has the potential of realizing efficient quantum gate, qubit entanglement and quantum information transfer. Here we report on the realization of the process in the superconducting Xmon and phase qutrits—two ladder-type three-level systems in which the ground state population is coherently transferred to the second excited state via the dark state subspace. We demonstrate that the population transfer efficiency is no less than 96% and 67% for the two devices, which agree well with the numerical simulation of the master equation. Population transfer via stimulated Raman adiabatic passage is significantly more robust against variations of the experimental parameters compared with that via the conventional resonant π pulse method. Our work opens up a new venue for exploring the process for quantum information processing using the superconducting artificial atoms.

Quantum state engineering necessitates transfer between quantum states. Here the authors demonstrate coherent population transfer between un- or weakly-coupled states of solid state systems, superconducting Xmon and phase qutrits, using stimulated Raman adiabatic passage and microwave driving.

Open reading frames of turnip crinkle virus involved in satellite symptom expression and incompatibility with Arabidopsis thaliana ecotype Dijon

Carmoviruses are single-stranded, single component RNA viruses that include turnip crinkle virus (TCV) and the recently discovered cardamine chlorotic fleck virus (CCFV). Full-length, biologically active cDNAs were constructed for the TCV-M isolate and the Blue Lake isolate of CCFV. Using chimeric viruses constructed between isolates of TCV that produce mild or severe symptoms when coinoculated with a virulent satellite RNA, a Glu residue at position 1,144 in the polymerase open reading frame was identified as being involved in satellite-mediated symptom expression. To analyze viral determinants involved in resistance, chimeric viruses with precisely exchanged open reading frames were produced between TCV, which does not infect the Arabidopsis thaliana ecotype Dijon (Di-0), and CCFV, which can infect Di-0, TCV with the coat protein of CCFV was able to systemically infect Di-0 although whole plant hybridizations revealed that the hybrid virus spread more slowly than either of the two parental viruses. These results indicate that the two parental viruses. These results indicate that the coat protein is an important viral determinant in the resistance of Di-0 to TCV.

Factors influencing operation time of laparoscopy-assisted distal subtotal gastrectomy: Analysis of consecutive 100 initial cases

AIMS

There is little information on patient selection criteria for laparoscopy-assisted distal gastrectomy (LADG) that would facilitate a successful initial experience for a surgeon new to the procedure. This study aimed to establish patient selection criteria that will allow increased proficiency and shorter operation times for the LADG procedure.

METHOD

One hundred LADG with lymphadenectomy and no other combined procedures were consecutively performed by one surgeon. These 100 consecutive LADG procedures were analyzed retrospectively from a prospectively designed computer database. Uni- and multivariate analyses were performed to identify factors influencing operation time.

RESULTS

According to univariate analysis, operation time was influenced by sex, BMI, surgical experience, and tumor location, whereas multivariate analysis indicated that operation time was significantly influenced only by BMI and surgical experience. The same analyses of only the first 50 cases showed that sex, BMI, surgical experience, and tumor location were independently associated with operation time. As BMI increased, so did operation time, whereas operation time decreased with increasing surgical experience.

CONCLUSION

This study suggests that surgeons who have limited experience with this advanced procedure may shorten operation time by considering patient and tumor characteristics in their early attempts at LADG. With a shortened operation time, surgeon with limited experience may become proficient to LADG rapidly.

An immediate endothelial cell signaling response to lung ischemia

Abrupt cessation of lung perfusion induces a rapid endothelial response that is not associated with anoxia but reflects loss of normal shear stress. This response includes membrane depolarization, H(2)O(2) generation, and increased intracellular Ca(2+). We evaluated these parameters immediately upon nonhypoxic ischemia using fluorescence videomicroscopy to image in situ endothelial cells in isolated, ventilated rat lungs. Lungs labeled with 4-(2-[6-(dioctylamino)-2-naphthalenyl]ethenyl)1-(3-sulfopropyl)-pyridinium (di-8-ANEPPS; a membrane potential probe), Amplex Red (an extracellular H(2)O(2) probe), or fluo 3-AM (a Ca(2+) indicator) were subjected to control perfusion followed by global ischemia. Endothelial di-8-ANEPPS fluorescence increased significantly within the first second of ischemia and stabilized at 15 s, indicating membrane depolarization by approximately 17 mV; depolarization was blocked by preperfusion with the K(+) channel agonist lemakalim. Increased H(2)O(2), inhibitable by catalase, was detected in the vascular space at 1-2 s after the onset of ischemia. Increased intracellular Ca(2+) was detected 10-15 s after the onset of ischemia; the initial increase was inhibited by preperfusion with thapsigargin. Thus the temporal sequence of the initial response of endothelial cells in situ to loss of shear stress (i.e., ischemia) is as follows: membrane depolarization, H(2)O(2) release, and increased intracellular Ca(2+).

Protective effects of low molecular weight chondroitin sulfate on amyloid beta (Aβ)-induced damage in vitro and in vivo

In the present study, we investigated the effects of low molecular weight chondroitin sulfate (LMWCS) on amyloid beta (Aβ)-induced neurotoxicity in vitro and in vivo. The in vitro results showed that LMWCS blocked Aβ25-35-induced cell viability loss and apoptosis, decreased intracellular calcium concentration, reactive oxygen species (ROS) levels, the mitochondrial membrane potential (MMP) depolarization, and the protein expression of Caspase-3. During in vivo experiments, LMWCS improved the cognitive impairment induced by Aβ1-40, increased the level of choline acetyltransferase (ChAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and decreased the level of malondialdehyde (MDA) and acetylcholinesterase (AChE) in the mouse brain. Moreover, LMWCS decreased the density of pyramidal cells of CA1 regions, and suppressed the protein expression of Bax/Bcl-2 and Caspase-3, -9 in the hippocampus of mice. In conclusion, LMWCS possessed neuroprotective properties against toxic effects induced by Aβ peptides both in vitro and in vivo, which might be related to anti-apoptotic activity. LMWCS might be a useful preventive and therapeutic compound for Alzheimer's disease.

Effect of phosphorylation on activities of Rap1A to interact with Raf-1 and to suppress Ras-dependent Raf-1 activation

Rap1A is phosphorylated by cAMP-dependent protein kinase (PKA), and this phosphorylation has been shown to modulate its interaction with other proteins. However, it is not known whether Rap1A phosphorylation is involved in regulation of its cellular functions, including suppression of Ras-dependent Raf-1 activation. We have previously shown that this suppressive activity of Rap1A is attributable to its greatly enhanced ability to bind to the cysteine-rich region (CRR, residues 152-184) of Raf-1 compared with that of Ras. Here, we show that phosphorylation of Rap1A by PKA abolished its binding activity to CRR. Furthermore, a mutant Rap1A(S180E), whose sole PKA phosphorylation residue, Ser-180, was substituted by an acidic residue, Glu, to mimic its phosphorylated form, failed to suppress Ras-dependent Raf-1 activation in COS-7 cells. These results indicate that the CRR binding activity and the Ras-suppressive function of Rap1A can be modulated through phosphorylation and suggest that Rap1A may function as a PKA-dependent regulator of Raf-1 activation, not merely as a suppressor.

Observation of Spin Splitting Torque in a Collinear Antiferromagnet RuO_{2}

Current-induced spin torques provide efficient data writing approaches for magnetic memories. Recently, the spin splitting torque (SST) was theoretically predicted, which combines advantages of conventional spin transfer torque (STT) and spin-orbit torque (SOT) as well as enables controllable spin polarization. Here we provide the experimental evidence of SST in collinear antiferromagnet RuO_{2} films. The spin current direction is found to be correlated to the crystal orientation of RuO_{2} and the spin polarization direction is dependent on (parallel to) the Néel vector. These features are quite characteristic for the predicted SST. Our finding not only presents a new member for the spin torques besides traditional STT and SOT, but also proposes a promising spin source RuO_{2} for spintronics.

Adjuvant Abemaciclib Combined with Endocrine Therapy for High Risk Early Breast Cancer: Safety and Patient-Reported Outcomes From the monarchE Study

BACKGROUND

In monarchE, abemaciclib plus endocrine therapy (ET) as adjuvant treatment of hormone receptor-positive, human epidermal growth factor 2-negative, high risk, early breast cancer demonstrated a clinically meaningful improvement in invasive disease-free survival versus ET alone. Detailed safety analyses conducted at a median follow-up of 27 months and key patient-reported outcomes (PRO) are presented.

PATIENTS AND METHODS

The safety population included all patients who received at least one dose of study treatment (n=5591). Safety analyses included incidence, management, and outcomes of common and clinically relevant adverse events (AEs). Patient-reported health-related quality-of-life, ET symptoms, fatigue, and side effect burden were assessed.

RESULTS

The addition of abemaciclib to ET resulted in higher incidence of Grade≥3 AEs (49.7% vs 16.3% with ET alone), predominantly laboratory cytopenias (e.g., neutropenia [19.6%]) without clinical complications. Abemaciclib-treated patients experienced more serious adverse events (SAEs; 13.3% vs 7.8%). Discontinuation of abemaciclib and/or ET due to AEs occurred in 18.5% of patients, mainly due to Grade1/2 AEs (66.8%). AEs were managed with comedications (e.g., antidiarrheals), abemaciclib dose holds (61.7%), and/or dose reductions (43.4%). Diarrhea was generally low grade (Grade1/2: 77%); Grade2/3 events were highest in the first month (20.5%), most short-lived (≤7 days) and did not recur. Venous thromboembolic events (VTE) were higher with abemaciclib+ET (2.5%) vs ET (0.6%); in the abemaciclib arm, increased VTE risk was observed with tamoxifen vs AIs (4.3% vs 1.8%). PROs were similar between arms, including being 'bothered by side effects of treatment', except for diarrhea. At ≥3 months, most patients reporting diarrhea reported "a little bit" or "somewhat".

CONCLUSION

In patients with high risk EBC, adjuvant abemaciclib+ET has an acceptable safety profile and tolerability is supported by PRO findings. Most AEs were reversible and manageable with comedications and/or dose modifications, consistent with the known abemaciclib toxicity profile.

HDAC1 and Klf4 interplay critically regulates human myeloid leukemia cell proliferation

Acute myeloid leukemia (AML) is recognized as a complex disease of hematopoietic stem cell disorders, but its pathogenesis mechanisms, diagnosis, and treatment remain unclear. General histone deacetylase (HDAC) inhibitors have been used in blood cancers including AML, but the lack of gene specificity greatly limits their anti-cancer effects and clinical applications. Here, we found that HDAC1 expression was negatively correlated with that of Krüppel-like factor 4 (Klf4) and that AML patients with lower HDAC1 level had better prognosis. Further, knockdown of HDAC1 in leukemia cells K562, HL-60, and U937 significantly increased Klf4 expression and inhibited cell cycle progression and cell proliferation, similar results were found for HDAC inhibitors (VPA and mocetinostat). Moreover, overexpression or knockdown of Klf4 could markedly block the effects of HDAC1 overexpression or knockdown on leukemia cells in vitro and in vivo, respectively. Mechanistic analyses demonstrated that HDAC1 and Klf4 competitively bound to the promoter region of Klf4 and oppositely regulated Klf4 expression in myeloid leukemia. We identified HDAC1 as a potential specific target for repressing cell proliferation and inducing cell cycle arrest through interplay and modulation of Klf4 expression, suggests that HDAC1 and Klf4 are potential new molecular markers and targets for clinical diagnosis, prognosis, and treatment of myeloid leukemia.

Spatiotemporal distribution, source apportionment and combined pollution of antibiotics in natural waters adjacent to mariculture areas in the Laizhou Bay, Bohai Sea

The spatiotemporal distribution, source apportionment and combined pollution of 14 antibiotics in natural waters adjacent to mariculture farms of Laizhou Bay in the Bohai Sea were studied. The contribution proportion and quantity of each potential pollution source to antibiotics in natural water bodies were quantitatively described. The correlations between heavy metals and antibiotics and their underlying mechanisms in natural and aquaculture water environment were analyzed. Fourteen antibiotics were detected in natural water and sediment in the coastal area of Laizhou Bay. The maximum concentrations of sulfamethazine and trimethoprim in water reached tens or even hundreds of μg/L in winter. Trimethoprim was the main antibiotic in natural water bodies in winter and summer, and enrofloxacin was the principal antibiotic in sediments. Enrofloxacin, ciprofloxacin and oxytetracycline were detected in all underground water samples; thus, control of these antibiotics needs to be made a priority to mitigate groundwater contamination. PCA-MLR revealed that the potential sources of antibiotics in natural waters of Laizhou Bay include the mariculture wastewater (18.3%), the domestic sewage (63.3%) and the livestock wastewater (18.4%). Therefore, the antibiotic burden of Laizhou Bay was principally from the domestic sewage. In natural water, the concentration of Cu was positively correlated with antibiotics, which might be related to the common sources, the competitive adsorption in sediments and the easy complexation characteristic of Cu and antibiotics. Positive correlations among antibiotics and heavy metals were observed in mariculture sediments, while negative relationships were observed in natural sediments.

A putative plant homolog of the yeast beta-1,3-glucan synthase subunit FKS1 from cotton (Gossypium hirsutum L.) fibers

A novel plant gene CFL1 was cloned from cotton (Gossypium hirsutum L.) fibers by expressed sequence tag (EST) database searching and 5'-RACE (rapid amplification of cDNA ends). This gene shows sequence homology with FKS1 which has been identified as the putative catalytic subunit of the yeast beta-1,3-glucan synthase. It encodes a protein (CFL1p) of 219 kDa with 13 deduced transmembrane helices and 2 large hydrophilic domains, one of which is at the N-terminus and the other in the internal region of the polypeptide. CFL1 displays 21% identity and 41% similarity to FKS1 at the amino acid level over its entire length, with 31% identity and 52% similarity for the hydrophilic central domain. Using RNA and protein blot analysis, CFL1 was found to be expressed at higher levels in cotton fibers during primary wall development. CFL1 also had a strong expression in young roots. Using a calmodulin (CaM)-gel overlay assay, the hydrophilic N-terminal domain of CFL1p was shown to bind to CaM, while the hydrophilic central domain did not. A putative CaM-binding domain, 16 amino acids long, was predicted in the hydrophilic N-terminal domain. Moreover, a product-entrapment assay demonstrated that a protein associated with an in vitro-synthesized callose pellet could be labeled by anti-CFL1 antibodies. Our finding suggests that CFL1 is a putative plant homolog of the yeast beta-1,3-glucan synthase subunit FKS1 and could be involved in callose synthesis.

Computational identification of citrus microRNAs and target analysis in citrus expressed sequence tags

MicroRNAs (miRNAs) are a new family of small RNA molecules found in plants and animals. We developed a comprehensive strategy for identifying new miRNA homologues by mining the repository of available citrus expressed sequence tags (ESTs). By adopting a range of filtering criteria, we identified a total of 38 potential miRNAs--nine, five, nine and 15 miRNAs in Citrus trifoliata (ctr-miRNAs), C. clementina (ccl-miRNAs), C. reticulata (crt-miRNAs) and C. sinensis (csi-miRNAs), respectively--from more than 430,000 EST sequences in citrus. Using the potential miRNA sequences, we conducted a further BLAST search of the mRNA database and found six potential target genes in these citrus species. Eight miRNAs were selected in order to verify their existence in citrus using Northern blotting, and the functions of several miRNAs in miRNA-mediated gene regulation are experimentally suggested. It appears that all these miRNAs regulate expression of their target genes by cleavage, which is the most common situation in gene regulation mediated by plant miRNAs. Our achievement in identifying new miRNAs in citrus provides a powerful incentive for further studies on the important roles of these miRNAs.

CB1 cannabinoid receptor: cellular regulation and distribution in N18TG2 neuroblastoma cells

In order to characterize cellular regulation of CB1 cannabinoid receptors, synthesis and turnover studies were performed. Metabolic labeling of N18TG2 cells with 35S-labeled amino acids was followed by immunoprecipitation from cell lysates using an affinity-purified antibody generated to the N-terminal 14-amino-acid segment of the CB1 receptor. During a 2 h labeling period, CB1 receptors were rapidly and constitutively synthesized (rate: 0.86%/min). The majority of newly synthesized CB1 cannabinoid receptors (70%) was degraded rapidly by a first-order process (t1/2=4.8 h). The remaining nascent receptors, which were degraded slowly (t1/2>24 h), may represent the pool of potentially functional receptors. Trypsin treatment of intact confluent cells, designed to cleave the extracellular antibody recognition site, did not alter the recovery of metabolically labeled immunoprecipitated CB1 receptors. This suggests that a large percentage of newly synthesized receptors was inaccessible to the protease and is probably intracellular. Immunocytochemistry revealed CB1 cannabinoid immunoreactivity both intracellularly and on the cell surface. Subcellular membrane fractions exhibited receptor binding activity on plasma membranes and nuclear-associated membranes. Only low-affinity binding was seen in the chromatin fraction. An hypothesis has been developed to explain these results and form the basis for future studies.

Tuning the entanglement between orbital reconstruction and charge transfer at a film surface

The interplay between orbital, charge, spin, and lattice degrees of freedom is at the core of correlated oxides. This is extensively studied at the interface of heterostructures constituted of two-layer or multilayer oxide films. Here, we demonstrate the interactions between orbital reconstruction and charge transfer in the surface regime of ultrathin (La,Sr)MnO₃, which is a model system of correlated oxides. The interactions are manipulated in a quantitative manner by surface symmetry-breaking and epitaxial strain, both tensile and compressive. The established charge transfer, accompanied by the formation of oxygen vacancies, provides a conceptually novel vision for the long-term problem of manganites—the severe surface/interface magnetization and conductivity deterioration. The oxygen vacancies are then purposefully tuned by cooling oxygen pressure, markedly improving the performances of differently strained films. Our findings offer a broad opportunity to tailor and benefit from the entanglements between orbit, charge, spin, and lattice at the surface of oxide films.

Spontaneous neuronal activity predicts intersubject variations in executive control of attention

Executive control of attention regulates our thoughts, emotion and behavior. Individual differences in executive control are associated with task-related differences in brain activity. But it is unknown whether attentional differences depend on endogenous (resting state) brain activity and to what extent regional fluctuations and functional connectivity contribute to individual variations in executive control processing. Here, we explored the potential contribution of intrinsic brain activity to executive control by using resting-state functional magnetic resonance imaging (fMRI). Using the amplitude of low-frequency fluctuations (ALFF) as an index of spontaneous brain activity, we found that ALFF in the right precuneus (PCUN) and the medial part of left superior frontal gyrus (msFC) was significantly correlated with the efficiency of executive control processing. Crucially, the strengths of functional connectivity between the right PCUN/left msFC and distributed brain regions, including the left fusiform gyrus, right inferior frontal gyrus, left superior frontal gyrus and right precentral gyrus, were correlated with individual differences in executive performance. Together, the ALFF and functional connectivity accounted for 67% of the variability in behavioral performance. Moreover, the strength of functional connectivity between specific regions could predict more individual variability in executive control performance than regionally specific fluctuations. In conclusion, our findings suggest that spontaneous brain activity may reflect or underpin executive control of attention. It will provide new insights into the origins of inter-individual variability in human executive control processing.