In vitro litholytic activity of some medicinal plants on urinary stones

Objective: This study was designed to evaluate the effect of plant extracts used in traditional medicine on the dissolution of three types of kidney stones.Subjects and methods: Kidney calculi of cystine; uric acid and pure carbapatite were incubated in vitro during 6 weeks in the presence of three of plant extracts and of 0.9% NaCl solution used as control. An extract of each plant was prepared by infusion of three grams of powdered plants during 30 min in 100 mL of a boiled NaCl 0.9% aqueous solution. Each extract was then filtered and thereafter set in a flask containing a stones. At the end of each week the stone was removed from the experimental medium and weighted after a 18 h drying at 40oC.Results: After 6 weeks of experiment and with in vitro study, we are observed that the aqueous extract of the seeds of Trigonella foenum-graecum has a better effect on dissolution of cystine and carbapatite stones (p < 0.05), with mass loss of 94 mg and 73 mg respectively at the end of experiment. While with NaCl solution, the mass was small.Conclusion: Our experiment failed to demonstrate a significant effect of the tested plant extracts to dissolve three types stones in vitro. However, we observed that only the extract of the seeds of T. foenum-graecum has a better effect on dissolution of cystine and carbapatite stones probably resulting from formation of complexes between stones and polyphenols or flavonoids present in the extracts

Evolutionarily stable defence and signalling of that defence

We examine the evolution and maintenance of defence and conspicuousness in prey species using a game theoretic model. In contrast to previous works, predators can raise as well as lower their attack probabilities as a consequence of encountering moderately defended prey. Our model predicts four distinct possibilities for evolutionarily stable strategies (ESSs) featuring maximum crypsis. Namely that such a solution can exist with (1) zero toxicity, (2) a non-zero but non-aversive level of toxicity, (3) a high, aversive level of toxicity or (4) that no such maximally cryptic solution exists. Maximally cryptic prey may still invest in toxins, because of the increased chance of surviving an attack (should they be discovered) that comes from having toxins. The toxin load of maximally cryptic prey may be sufficiently strong that the predators will find them aversive, and seek to avoid similar looking prey in future. However, this aversiveness does not always necessarily trigger aposematic signalling, and highly toxic prey can still be maximally cryptic, because the increased initial rate of attack from becoming more conspicuous is not necessarily always compensated for by increased avoidance of aversive prey by predators. In other circumstances, the optimal toxin load may be insufficient to generate aversion but still be non-zero (because it increases survival), and in yet other circumstances, it is optimal to make no investment in toxins at all. The model also predicts ESSs where the prey are highly defended and aversive and where this defence is advertised at a cost of increased conspicuousness to predators. In many circumstances there is an infinite array of these aposematic ESSs, where the precise appearance is unimportant as long as it is highly visible and shared by all members of the population. Yet another class of solutions is possible where there is strong between-individual variation in appearance between conspicuous, poorly defended prey

Direct and converse magnetoelectric effects in Metglas/LiNbO3/Metglas trilayers

Electromechanical and magnetoelectric properties of Metglas/LiNbO3/Metglas trilayers have been studied in the frequency range from 20 Hz to 0.4 MHz. A trilayer of Metglas/PMN-PT/Metglas prepared in the same way was used as a reference. Though PMN-PT has much larger charge piezocoefficients than LiNbO3 (LNO), the direct magnetoelectric voltage coefficient is found to be comparable in both trilayers due to the much lower dielectric permittivity of LNO. The magnitude of the direct magnetoelectric effect in the LNO trilayers is about 0.4 V/cm Oe in the quasistatic regime and about 90 V/cm Oe at the electromechanical resonance. Calculations show that the magnetoelectric properties can be significantly improved (up to 500 V/cm Oe) via controlling the cut angle of LNO, choosing the appropriate thickness ratio of the ferroelectric/ferromagnetic layers and a better bonding between Metglas and LNO. Advantages of using LiNbO3-type ferroelectrics in magnetoelectric composites are discussed. (C) 2013 AIP Publishing LLC

Coreceptor affinity for MHC defines peptide specificity requirements for TCR interaction with coagonist peptide–MHC

Recent work has demonstrated that nonstimulatory endogenous peptides can enhance T cell recognition of antigen, but MHCI- and MHCII-restricted systems have generated very different results. MHCII-restricted TCRs need to interact with the nonstimulatory peptide–MHC (pMHC), showing peptide specificity for activation enhancers or coagonists. In contrast, the MHCI-restricted cells studied to date show no such peptide specificity for coagonists, suggesting that CD8 binding to noncognate MHCI is more important. Here we show how this dichotomy can be resolved by varying CD8 and TCR binding to agonist and coagonists coupled with computer simulations, and we identify two distinct mechanisms by which CD8 influences the peptide specificity of coagonism. Mechanism 1 identifies the requirement of CD8 binding to noncognate ligand and suggests a direct relationship between the magnitude of coagonism and CD8 affinity for coagonist pMHCI. Mechanism 2 describes how the affinity of CD8 for agonist pMHCI changes the requirement for specific coagonist peptides. MHCs that bind CD8 strongly were tolerant of all or most peptides as coagonists, but weaker CD8-binding MHCs required stronger TCR binding to coagonist, limiting the potential coagonist peptides. These findings in MHCI systems also explain peptide-specific coagonism in MHCII-restricted cells, as CD4–MHCII interaction is generally weaker than CD8–MHCI.National Institutes of Health (U.S.). Pioneer Awar

Association Between Serum Uric Acid and Development of Type 2 Diabetes

OBJECTIVE To systematically evaluate the association between serum uric acid (SUA) level and subsequent development of type 2 diabetes.RESEARCH DESIGN AND METHODS We searched Medline (31 March from 1966 to 2009) and Embase (31 March from 1980 to 2009) for observational cohort studies examining the association between SUA and the risk of type 2 diabetes by manual literature search. Relative risks (RRs) for each 1 mg/dl increase in SUA were pooled by using a random-effects model. The studies included were stratified into subgroups representing different study characteristics, and meta-regression analyses were performed to investigate the effect of these characteristics on the association between SUA level and type 2 diabetes risk.RESULTS The search yielded 11 cohort studies (42,834 participants) that reported 3,305 incident cases of type 2 diabetes during follow-up periods ranging from 2.0 to 13.5 years. The pooled RR of a 1 mg/dl increase in SUA was 1.17 (95% CI 1.09–1.25). Study results were consistently significant (i.e., >1) across characteristics of participants and study design. Publication bias was both visually and statistically suggested (P = 0.03 for Egger\u27s test, 0.06). Adjustment for publication bias attenuated the pooled RR per mg/dl increase in SUA (RR 1.11 [95% CI 1.03–1.20]), but the association remained statistically significant (P = 0.009).CONCLUSIONS The current meta-analysis suggests that SUA level is positively associated with the development of type 2 diabetes regardless of various study characteristics. Further research should attempt to determine whether it is effective to utilize SUA level as a predictor of type 2 diabetes for its primary prevention

Is Japan Really Back? The "Abe Doctrine" and Global Governance

Japanese Prime Minister Abe Shinzo has emerged as the “comeback kid” of Japanese politics and in his second term of office is now widely regarded as a rare example of strong leadership as he seeks to arrest and reverse his country’s perceived decline. The strategy to achieve these objectives has come to be known as the “Abe Doctrine,” which represents a radical but risky shift in foreign policy. This article outlines the tenets of the evolving Abe Doctrine and then applies them to the Abe administration’s behaviour in the mechanisms of global governance, a highly pertinent but overlooked example. It argues that although a more strategic and coherent approach to global governance has emerged under Abe than had been previously evident, this has been at the expense of the norm of internationalism that has traditionally shaped Japan’s role

Organism-sediment interactions govern post-hypoxia recovery of ecosystem functioning

Hypoxia represents one of the major causes of biodiversity and ecosystem functioning loss for coastal waters. Since eutrophication-induced hypoxic events are becoming increasingly frequent and intense, understanding the response of ecosystems to hypoxia is of primary importance to understand and predict the stability of ecosystem functioning. Such ecological stability may greatly depend on the recovery patterns of communities and the return time of the system properties associated to these patterns. Here, we have examined how the reassembly of a benthic community contributed to the recovery of ecosystem functioning following experimentally-induced hypoxia in a tidal flat. We demonstrate that organism-sediment interactions that depend on organism size and relate to mobility traits and sediment reworking capacities are generally more important than recovering species richness to set the return time of the measured sediment processes and properties. Specifically, increasing macrofauna bioturbation potential during community reassembly significantly contributed to the recovery of sediment processes and properties such as denitrification, bedload sediment transport, primary production and deep pore water ammonium concentration. Such bioturbation potential was due to the replacement of the small-sized organisms that recolonised at early stages by large-sized bioturbating organisms, which had a disproportionately stronger influence on sediment. This study suggests that the complete recovery of organism-sediment interactions is a necessary condition for ecosystem functioning recovery, and that such process requires long periods after disturbance due to the slow growth of juveniles into adult stages involved in these interactions. Consequently, repeated episodes of disturbance at intervals smaller than the time needed for the system to fully recover organism-sediment interactions may greatly impair the resilience of ecosystem functioning.

Minority-carrier lifetime and photoresponse properties of B-doped p-BaSi2, a potential light absorber for solar cells

600-nm-thick B-doped p-BaSi2 layers were grown on (111)-oriented n-Si substrates by molecular beam epitaxy, and the dependences of the minority carrier lifetime τ and photoresponsivity on the hole concentration p were investigated. p was varied from 1.4 × 1016 to 3.9 × 1018 cm−3. The highest τ of 2 µs was obtained for the sample with the lowest p of 1.4 × 1016 cm−3, reaching two orders of magnitude higher than that of the sample with the highest p of 3.9 × 1018 cm−3. The low-concentration-doped sample also exhibited an excellent external quantum efficiency (EQE) as large as 80% at a wavelength of approximately 800 nm at a reverse bias voltage of 0.2 V. This value is higher than any other EQEs we have ever achieved for BaSi2, showing the great potential of p-BaSi2 as a light absorber in solar cells

Peptide-MHC heterodimers show that thymic positive selection requires a more restricted set of self-peptides than negative selection

T cell selection and maturation in the thymus depends on the interactions between T cell receptors (TCRs) and different self-peptide–major histocompatibility complex (pMHC) molecules. We show that the affinity of the OT-I TCR for its endogenous positively selecting ligands, Catnb-H-2Kb and Cappa1-H-2Kb, is significantly lower than for previously reported positively selecting altered peptide ligands. To understand how these extremely weak endogenous ligands produce signals in maturing thymocytes, we generated soluble monomeric and dimeric peptide–H-2Kb ligands. Soluble monomeric ovalbumin (OVA)-Kb molecules elicited no detectable signaling in OT-I thymocytes, whereas heterodimers of OVA-Kb paired with positively selecting or nonselecting endogenous peptides, but not an engineered null peptide, induced deletion. In contrast, dimer-induced positive selection was much more sensitive to the identity of the partner peptide. Catnb-Kb–Catnb-Kb homodimers, but not heterodimers of Catnb-Kb paired with a nonselecting peptide-Kb, induced positive selection, even though both ligands bind the OT-I TCR with detectable affinity. Thus, both positive and negative selection can be driven by dimeric but not monomeric ligands. In addition, positive selection has much more stringent requirements for the partner self-pMHC

Absence of the MGMT protein as well as methylation of the MGMT promoter predict the sensitivity for temozolomide

The DNA repair protein O(6)-methylguanine-DNA methyltransferase (MGMT) can cause resistance to the alkylating drug temozolomide (TMZ). The purpose of this study was to determine the relationship between the MGMT status, determined by means of several techniques and methods, and the cytotoxic response to TMZ in 11 glioblastoma multiforme (GBM) cell lines and 5 human tumour cell lines of other origins. Cell survival was analysed by clonogenic assay. The MGMT protein levels were assessed by western blot analysis. The MGMT promoter methylation levels were determined using methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) and quantitative real-time methylation-specific PCR (qMSP). On the basis of the results of these techniques, six GBM cell lines were selected and subjected to bisulphite sequencing. The MGMT protein was detected in all TMZ-resistant cell lines, whereas no MGMT protein could be detected in cell lines that were TMZ sensitive. The MS-MLPA results were able to predict TMZ sensitivity in 9 out of 16 cell lines (56%). The qMSP results matched well with TMZ sensitivity in 11 out of 12 (92%) glioma cell lines. In addition, methylation as detected by bisulphite sequencing seemed to be predictive of TMZ sensitivity in all six cell lines analysed (100%). The MGMT protein expression more than MGMT promoter methylation status predicts the response to TMZ in human tumour cell line