Investigation of the spectral characteristics of Sm3+ ions in lead borosilicate glass for photonic applications

Different concentrations of Sm₂O₃-doped lead borosilicate glass were synthesized using a melt–quenching method and their characteristics were analyzed using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy absorption, emission, and decay curves. From the XRD patterns, the noncrystalline nature of titled glass was confirmed. The structural groups that existed in the host glass were observed from FTIR spectra. The Judd–Ofelt (JO) intensity parameters and oscillator strengths were derived from the absorption spectra and compared with various reported systems. The excitation luminescence levels of the Sm³⁺ ion radiative properties were further computed using the JO intensity parameters. Effective bandwidth, emission cross-sections (σ_e), and several lasing properties were assessed from emission spectra and compared with other reported glass systems. The decay curves of the ⁴G_5/2 level of Sm³⁺ ion were also been measured and examined. Additionally, the colour coordinates of the Commission International de I'Éclairage chromaticity were assessed. The titled glass were suitable for visible reddish orange luminescence devices based on all obtained parameters.     

Synthesis,Anticancer Evaluation and in Silico Studies of 1,4-Dihydropyridines

An efficient 1,4-dihydropyridine synthesis under mild conditions has been developed. Numerous substrates were tested, with yields of 1,4-dihydropridines ranging from good to excellent and a wide range of functional group tolerance. A549, HT-29, and HepG2 cancer cells were used to investigate the anticancer efficacy of each of the produced compounds. Additionally, in-silico docking studies were conducted to understand the structure-based features of the anticancer mechanism with the cancer medication target of Adenosine A2A receptor as well as the molecular level interactions of the compounds.     

Synthesis,cytotoxic activity and structure–activity relationships of hedychenone analogues

Hedychenone, a plant-derived labdane diterpenoid, showed potent in vitro cytotoxic activity against cancerous cells. In the present study, a series of analogues have been synthesized by modification of the furanoid ring, double bond and the vinylic methyl functionality of this natural product lead and evaluated for their cytotoxic activities against human cancer cell lines. The structures of the target compounds were established by IR, ¹H NMR and mass spectral analysis. Majority of the analogues displayed potent activity than the parent compound, hedychenone. Preliminary structure–activity relationship studies indicated that furanoid ring has a greater impact on cytotoxicity than that of the decalone nucleus. However, dimerization through C-8 significantly enhanced the cytotoxic activity of the hedychenone.     

Fast Charging Materials for High Power Applications

An overview of fast charging materials for high power applications is given. The behavior at high current density of several anodic and cathodic materials that have been utilized in lithium‐, sodium‐, and potassium‐ion batteries is considered. Furthermore, the behavior of capacitive and pseudocapacitive materials suitable for electrochemical capacitors and, also, of those that have been utilized for the realization of hybrid‐ion capacitors, which are nowadays an interesting reality in the field of high power devices, is discussed. The advantages and limitations of all these materials are critically analyzed with the aim of understanding their impact on real devices. On the basis of this analysis, the most important aspects are identified, which should be addressed in the future for the realization of advanced high power devices.     

Plant Probiotic Bacterial Endophyte,Alcaligenes faecalis,Modulates Plant Growth and Forskolin Biosynthesis in Coleus forskohlii

Probiotics and Antimicrobial Proteins - Coleus forskohlii is an herb, well-known for its medicinal compound forskolin present in its roots, with wide range of pharmaceutical applications. Here, we...     

Genome wide identification,characterization and validation of novel miRNA-based SSR markers in pomegranate ( Punica granatum L.)

A total of 17,439 mature miRNAs (~ 21 nt) earlier generated through RNA seq in the pomegranate were used for in silico analysis. After complexity reduction, a total of 1922 representative mature miRNAs were selected and used as query sequences against pomegranate genome to retrieve 2540 homologous contigs with flanking regions (~ 800). By using pre-miRNA prediction web server, a total of 1028 true contigs harbouring pri-miRNAs encoding 1162 pre-miRNAs were identified. Survey of these sequences for SSRs yielded a total of 1358 and 238 SSRs specific to pri-miRNA and pre-miRNAs, respectively. Of these, primer pairs were designed for 897 pri-miRNA and 168 pre-miRNA SSRs. In pri-miRNA sequences, hexa-nucleotides repeats were found to be most abundant (44.18%) followed by mono- (18.41%) and di-nucleotide (17.01%), which is also observed in pre-miRNA sequences. Further, a set of 51 randomly selected pre-miRNA-SSRs was examined for marker polymorphism. The experimental validation of these markers on eight pomegranate genotypes demonstrated 92.15% polymorphism. Utility of these functional markers was confirmed via examination of genetic diversity of 18 pomegranate genotypes using 15 miRNA-SSRs. Further, potential application of miRNA-SSRs for discovery of trait specific candidate genes was showed by validating 51 mature miRNA against publically available 2047 EST sequences of pomegranate by target and network analysis. In summary, the current study offers novel functional molecular markers for pomegranate genetic improvement.     

Structural Integrity of the Greek Key Motif in βγ-Crystallins Is Vital for Central Eye Lens Transparency

Background

We highlight an unrecognized physiological role for the Greek key motif, an evolutionarily conserved super-secondary structural topology of the βγ-crystallins. These proteins constitute the bulk of the human eye lens, packed at very high concentrations in a compact, globular, short-range order, generating transparency. Congenital cataract (affecting 400,000 newborns yearly worldwide), associated with 54 mutations in βγ-crystallins, occurs in two major phenotypes nuclear cataract, which blocks the central visual axis, hampering the development of the growing eye and demanding earliest intervention, and the milder peripheral progressive cataract where surgery can wait. In order to understand this phenotypic dichotomy at the molecular level, we have studied the structural and aggregation features of representative mutations.

Methods

Wild type and several representative mutant proteins were cloned, expressed and purified and their secondary and tertiary structural details, as well as structural stability, were compared in solution, using spectroscopy. Their tendencies to aggregate in vitro and in cellulo were also compared. In addition, we analyzed their structural differences by molecular modeling in silico.

Results

Based on their properties, mutants are seen to fall into two classes. Mutants A36P, L45PL54P, R140X, and G165fs display lowered solubility and structural stability, expose several buried residues to the surface, aggregate in vitro and in cellulo, and disturb/distort the Greek key motif. And they are associated with nuclear cataract. In contrast, mutants P24T and R77S, associated with peripheral cataract, behave quite similar to the wild type molecule, and do not affect the Greek key topology.

Conclusion

When a mutation distorts even one of the four Greek key motifs, the protein readily self-aggregates and precipitates, consistent with the phenotype of nuclear cataract, while mutations not affecting the motif display ‘native state aggregation’, leading to peripheral cataract, thus offering a protein structural rationale for the cataract phenotypic dichotomy “distort motif, lose central vision”.     

Defining the Vulnerable Period for Re-Establishment of Clostridium difficile Colonization after Treatment of C. difficile Infection with Oral Vancomycin or Metronidazole

Background

Clostridium difficile is an anaerobic, spore-forming bacterium that is the most common cause of healthcare-associated diarrhea in developed countries. A significant proportion of patients receiving oral vancomycin or metronidazole for treatment of Clostridium difficile infection (CDI) develop recurrences. However, the period of vulnerability to re-establishment of colonization by C. difficile after therapy is not well defined.

Principal Findings

In a prospective study of CDI patients, we demonstrated that most vancomycin-treated patients maintained inhibitory concentrations of vancomycin in stool for 4 to 5 days after therapy, whereas metronidazole was only detectable during therapy. From the time of elimination of the antibiotics to 14 to 21 days after therapy, a majority of stool suspensions supported growth of C. difficile and deep 16S rRNA sequencing demonstrated persistent marked alteration of the indigenous microbiota. By 21 to 28 days after completion of CDI treatment, a majority of stool suspensions inhibited growth of C. difficile and there was evidence of some recovery of the microbiota.

Conclusions

These data demonstrate that there is a vulnerable period for re-establishment of C. difficile colonization after CDI treatment that begins within a few days after discontinuation of treatment and extends for about 3 weeks in most patients.