Design, synthesis and characterization of hydroxyapatite-chitosan nanocomposite radiolabelled with 153Sm as radiopharmaceutical for use in radiosynovectomy

Abstract The aim of the present study was to introduction of hydroxyapatite/chitosan nanocomposite as a new radiosynovectomy agent with excellent properties. In this work, the nanocomposite was prepared through a reliable method and characterized using different techniques to elucidate its chemical structure and physiochemical properties. The prepared nanocomposite was successfully radiolabeled with 153Sm under optimal conditions and with high radiolabelling yield (99 %). The radiochemical purity of the prepared radiopharmaceutical was found to be >99 % as determined by ITLC technique. In vitro stability studies in saline solution and in human serum showed that the radiolabeled nanocomposite retained its stability for at least 6 days. The biodistribution and imaging studies in wild-type rats revealed high retention of the agent into the synovial joints of the knee even at 96 h post-injection, thereby indicating excellent in vivo stability of 153Sm labeled hydroxyapatite-chitosan nanocomposite. Therefore, the prepared radiopharmaceutical would be a potential therapeutic agent for use in radiosynovectomy procedure.

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Design, Synthesis and Characterization of Some Novel benzamide derivatives and it's Pharmacological Screening

International Journal of Scientific Research in Science and Technology ◽

10.32628/ijsrst20723 ◽

2020 ◽

pp. 68-74 ◽

Cited By ~ 4

Author(s):

Akshay R. Yadav ◽

Shrinivas K. Mohite

Keyword(s):

Chemical Structure ◽

Design Synthesis ◽

Different Types ◽

Anti Inflammatory ◽

Benzoyl Isothiocyanate ◽

Pharmacological Screening ◽

Benzamide Derivatives

The new series of substituted N-(phenylcarbamothioyl)benzamide derivatives (2a-2f) was designed, development and synthesized by using conventional and microwave method. In present work 6 different N-(phenylcarbamothioyl)benzamide were synthesized. Substituted benzoyl chloride is converted into benzoyl isothiocyanate by esterification. Benzoyl isothiocyanate is converted into Substituted (phenylcarbamothioyl)benzamide by treating with different types of substituted aniline. Confirmation of the chemical structure of the synthesized was substantiated by TLC, IR, 1H NMR, MS spectroscopy.Novel synthesized compounds screened for their in vivo and in-vitro anti-inflammatory studies and compound 2f shows promising anti-inflammatory activity.

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Biochemical and genetic characterization of a yeast TFIID mutant that alters transcription in vivo and DNA binding in vitro

Molecular and Cellular Biology ◽

10.1128/mcb.12.5.2372-2382.1992 ◽

1992 ◽

Vol 12 (5) ◽

pp. 2372-2382

Author(s):

K M Arndt ◽

S L Ricupero ◽

D M Eisenmann ◽

F Winston

Keyword(s):

Amino Acid ◽

Dna Binding ◽

Direct Repeat ◽

Single Amino Acid ◽

Wild Type ◽

Dna Binding Specificity ◽

Selection For

A mutation in the gene that encodes Saccharomyces cerevisiae TFIID (SPT15), which was isolated in a selection for mutations that alter transcription in vivo, changes a single amino acid in a highly conserved region of the second direct repeat in TFIID. Among eight independent spt15 mutations, seven cause this same amino acid change, Leu-205 to Phe. The mutant TFIID protein (L205F) binds with greater affinity than that of wild-type TFIID to at least two nonconsensus TATA sites in vitro, showing that the mutant protein has altered DNA binding specificity. Site-directed mutations that change Leu-205 to five different amino acids cause five different phenotypes, demonstrating the importance of this amino acid in vivo. Virtually identical phenotypes were observed when the same amino acid changes were made at the analogous position, Leu-114, in the first repeat of TFIID. Analysis of these mutations and additional mutations in the most conserved regions of the repeats, in conjunction with our DNA binding results, suggests that these regions of the repeats play equivalent roles in TFIID function, possibly in TATA box recognition.

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Characterization of New Virulence Factors Involved in the Intracellular Growth and Survival of Burkholderia pseudomallei

Infection and Immunity ◽

10.1128/iai.01102-15 ◽

2015 ◽

Vol 84 (3) ◽

pp. 701-710 ◽

Cited By ~ 23

Author(s):

Madeleine G. Moule ◽

Natasha Spink ◽

Sam Willcocks ◽

Jiali Lim ◽

José Afonso Guerra-Assunção ◽

...

Keyword(s):

Burkholderia Pseudomallei ◽

Insertion Site ◽

Wild Type ◽

Content Type ◽

Growth And Survival ◽

New Genes ◽

Insertion Sites

Burkholderia pseudomallei, the causative agent of melioidosis, has complex and poorly understood extracellular and intracellular lifestyles. We used transposon-directed insertion site sequencing (TraDIS) to retrospectively analyze a transposon library that had previously been screened through a BALB/c mouse model to identify genes important for growth and survivalin vivo. This allowed us to identify the insertion sites and phenotypes of negatively selected mutants that were previously overlooked due to technical constraints. All 23 unique genes identified in the original screen were confirmed by TraDIS, and an additional 105 mutants with various degrees of attenuationin vivowere identified. Five of the newly identified genes were chosen for further characterization, and clean, unmarkedbpsl2248,tex,rpiR,bpsl1728, andbpss1528deletion mutants were constructed from the wild-type strain K96243. Each of these mutants was testedin vitroandin vivoto confirm their attenuated phenotypes and investigate the nature of the attenuation. Our results confirm that we have identified new genes important toin vivovirulence with roles in different stages ofB. pseudomalleipathogenesis, including extracellular and intracellular survival. Of particular interest, deletion of the transcription accessory protein Tex was shown to be highly attenuating, and thetexmutant was capable of providing protective immunity against challenge with wild-typeB. pseudomallei, suggesting that the genes identified in our TraDIS screen have the potential to be investigated as live vaccine candidates.

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Design, Synthesis, In Vitro, and In Vivo Characterization of Phenylpiperazines and Pyridinylpiperazines as Potent and Selective Antagonists of the Melanocortin-4 Receptor

Journal of Medicinal Chemistry ◽

10.1021/jm701137s ◽

2007 ◽

Vol 50 (25) ◽

pp. 6356-6366 ◽

Cited By ~ 12

Author(s):

Joe A. Tran ◽

Wanlong Jiang ◽

Fabio C. Tucci ◽

Beth A. Fleck ◽

Jenny Wen ◽

...

Keyword(s):

Design Synthesis ◽

Selective Antagonists ◽

Melanocortin 4 Receptor ◽

In Vivo Characterization

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Purification and Characterization of aBacillus subtilis168 Nuclease, YokF, Involved in Chromosomal DNA Degradation and Cell Death Caused by Thermal Shock Treatments

Journal of Biological Chemistry ◽

10.1074/jbc.m106205200 ◽

2001 ◽

Vol 276 (50) ◽

pp. 47046-47051 ◽

Cited By ~ 10

Author(s):

Jin J. Sakamoto ◽

Miho Sasaki ◽

Tetsuaki Tsuchido

Keyword(s):

Thermal Shock ◽

Nuclease Activity ◽

Dna Degradation ◽

Wild Type ◽

Chromosomal Dna ◽

Purification And Characterization ◽

Membrane Perturbation

We purified and characterized a 39-kDaBacillus subtilis168 nuclease that has been suggested in this laboratory to be involved in chromosomal DNA degradation induced by lethal heat and cold shock treatmentsin vivo. The nuclease activity was inhibitedin vitroby aurintricalboxylic acid but not by Zn2+. By the mutant analysis, we identified the 39-kDa nuclease as a product ofyokFgene. TheyokFgene contained a putative lipoprotein signal peptide motif. Afterin vivoexposure to lethal heat and cold stresses, the chromosomal DNA fragmentation was reduced in theyokFmutant, which demonstrated about a 2–10-fold higher survival rate than the wild type. TheyokFmutant was found to be more sensitive to mitomycin C than the wild type. The transformation efficiency of theyokFmutant was about 10 times higher than that of the wild type. It is suggested that whenB. subtiliscells are exposed to a stressful thermal shock resulting in membrane perturbation, YokF nuclease consequently dislocates into the cytoplasm and then attacks DNA.

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Construction and Phenotypic Characterization of an Auxotrophic Mutant of Mycobacterium tuberculosis Defective in l-Arginine Biosynthesis

Infection and Immunity ◽

10.1128/iai.70.6.3080-3084.2002 ◽

2002 ◽

Vol 70 (6) ◽

pp. 3080-3084 ◽

Cited By ~ 55

Author(s):

Bhavna G. Gordhan ◽

Debbie A. Smith ◽

Heidi Alderton ◽

Ruth A. McAdam ◽

Gregory J. Bancroft ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Mutant Strain ◽

Auxotrophic Mutant ◽

Phenotypic Characterization ◽

Wild Type ◽

Arginine Biosynthesis ◽

High Concentrations

ABSTRACT A mutant of Mycobacterium tuberculosis defective in the metabolism of l-arginine was constructed by allelic exchange mutagenesis. The argF mutant strain required exogenous l-arginine for growth in vitro, and in the presence of 0.96 mM l-arginine, it achieved a growth rate and cell density in stationary phase comparable to those of the wild type. The mutant strain was also able to grow in the presence of high concentrations of argininosuccinate, but its auxotrophic phenotype could not be rescued by l-citrulline, suggesting that the ΔargF::hyg mutation exerted a polar effect on the downstream argG gene but not on argH. The mutant strain displayed reduced virulence in immunodeficient SCID mice and was highly attenuated in immunocompetent DBA/2 mice, suggesting that l-arginine availability is restricted in vivo.

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Identification of a Bidirectional Splicing Enhancer: Differential Involvement of SR Proteins in 5′ or 3′ Splice Site Activation

Molecular and Cellular Biology ◽

10.1128/mcb.19.11.7347 ◽

1999 ◽

Vol 19 (11) ◽

pp. 7347-7356 ◽

Cited By ~ 43

Author(s):

Cyril F. Bourgeois ◽

Michel Popielarz ◽

Georges Hildwein ◽

James Stevenin

Keyword(s):

Splice Site ◽

Sr Proteins ◽

Dependent Manner ◽

Wild Type ◽

Adenovirus E1a ◽

Differential Involvement ◽

Splicing Enhancer

ABSTRACT The adenovirus E1A pre-mRNA undergoes alternative splicing whose modulation occurs during infection, through the use of three different 5′ splice sites and of one major or one minor 3′ splice site. Although this pre-mRNA has been extensively used as a model to compare the transactivation properties of SR proteins, no cis-acting element has been identified in the transcript sequence. Here we describe the identification and the characterization of a purine-rich splicing enhancer, located just upstream of the 12S 5′ splice site, which is formed from two contiguous 9-nucleotide (nt) purine motifs (Pu1 and Pu2). We demonstrate that this sequence is a bidirectional splicing enhancer (BSE) in vivo and in vitro, because it activates both the downstream 12S 5′ splice site through the Pu1 motif and the upstream 216-nt intervening sequence (IVS) 3′ splice site through both motifs. UV cross-linking and immunoprecipitation experiments indicate that the BSE interacts with several SR proteins specifically, among them 9G8 and ASF/SF2, which bind preferentially to the Pu1 and Pu2 motifs, respectively. Interestingly, we show by in vitro complementation assays that SR proteins have distinct transactivatory properties. In particular, 9G8, but not ASF/SF2 or SC35, is able to strongly activate the recognition of the 12S 5′ splice site in a BSE-dependent manner in wild-type E1A or in a heterologous context, whereas ASF/SF2 or SC35, but not 9G8, activates the upstream 216-nt IVS splicing. Thus, our results identify a novel exonic BSE and the SR proteins which are involved in its differential activity.

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Identification and Characterization of the Bacillus thuringiensis phaZ Gene, Encoding New Intracellular Poly-3-Hydroxybutyrate Depolymerase

Journal of Bacteriology ◽

10.1128/jb.00729-06 ◽

2006 ◽

Vol 188 (21) ◽

pp. 7592-7599 ◽

Cited By ~ 33

Author(s):

Chi-Ling Tseng ◽

Hui-Ju Chen ◽

Gwo-Chyuan Shaw

Keyword(s):

Bacillus Thuringiensis ◽

Wild Type ◽

Gene Encoding ◽

Significant Similarity ◽

Phb Depolymerase ◽

New Type ◽

Identification And Characterization

ABSTRACTA gene that codes for a novel intracellular poly-3-hydroxybutyrate (PHB) depolymerase has now been identified in the genome ofBacillus thuringiensissubsp.israelensisATCC 35646. This gene, previously annotated as a hypothetical 3-oxoadipate enol-lactonase (PcaD) gene and now designatedphaZ, encodes a protein that shows no significant similarity with any known PHB depolymerase. Purified His-tagged PhaZ could efficiently degrade trypsin-activated native PHB granules as well as artificial amorphous PHB granules and release 3-hydroxybutyrate monomer as a hydrolytic product, but it could not hydrolyze denatured semicrystalline PHB. In contrast, purified His-tagged PcaD ofPseudomonas putidawas unable to degrade trypsin-activated native PHB granules and artificial amorphous PHB granules. TheB. thuringiensisPhaZ was inactive againstp-nitrophenylpalmitate, tributyrin, and triolein. Sonication supernatants of the wild-typeB. thuringiensiscells exhibited a PHB-hydrolyzing activity in vitro, whereas those prepared from aphaZmutant lost this activity. ThephaZmutant showed a higher PHB content than the wild type at late stationary phase of growth in a nutrient-rich medium, indicating that this PhaZ can function as a PHB depolymerase in vivo. PhaZ contains a lipase box-like sequence (G-W-S102-M-G) but lacks a signal peptide. A purified His-tagged S102A variant had lost the PHB-hydrolyzing activity. Taken together, these results indicate thatB. thuringiensisharbors a new type of intracellular PHB depolymerase.

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Chemokine CCL28 Is a Potent Therapeutic Agent for Oropharyngeal Candidiasis

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00210-20 ◽

2020 ◽

Vol 64 (8) ◽

Author(s):

Jie He ◽

Monica A. Thomas ◽

Jaime de Anda ◽

Michelle W. Lee ◽

Emma Van Why ◽

...

Keyword(s):

Therapeutic Agent ◽

Opportunistic Infections ◽

Membrane Disruption ◽

Oropharyngeal Candidiasis ◽

Wild Type ◽

Content Type ◽

Immunodeficient Mice ◽

Drug Classes

ABSTRACT Candida albicans is a commensal organism that causes life-threatening or life-altering opportunistic infections. Treatment of Candida infections is limited by the paucity of antifungal drug classes. Naturally occurring antimicrobial peptides are promising agents for drug development. CCL28 is a CC chemokine that is abundant in saliva and has in vitro antimicrobial activity. In this study, we examine the in vivo Candida killing capacity of CCL28 in oropharyngeal candidiasis as well as the spectrum and mechanism of anti-Candida activity. In the mouse model of oropharyngeal candidiasis, application of wild-type CCL28 reduces oral fungal burden in severely immunodeficient mice without causing excessive inflammation or altering tissue neutrophil recruitment. CCL28 is effective against multiple clinical strains of C. albicans. Polyamine protein transporters are not required for CCL28 anti-Candida activity. Both structured and unstructured CCL28 proteins show rapid and sustained fungicidal activity that is superior to that of clinical antifungal agents. Application of wild-type CCL28 to C. albicans results in membrane disruption as measured by solute movement, enzyme leakage, and induction of negative Gaussian curvature on model membranes. Membrane disruption is reduced in CCL28 lacking the functional C-terminal tail. Our results strongly suggest that CCL28 can exert antifungal activity in part via membrane permeation and has potential for development as an anti-Candida therapeutic agent without inflammatory side effects.

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