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The molecular structure of the title compound, C14H18Br2N2O2, has one half-molecule in the asymmetric unit. The molecule has a crystallographic inversion centre in the middle of the benzene ring. The C—C—N—C torsion angle between the benzene ring and the bromoamide group is 149.2 (7)°. The crystal is stabilized by a strong intermolecular N—H...O bond and weak C—H...O interactions. These contacts give rise to a three-dimensional network.

In the title compound, C12H14O2S3, a chain transfer agent (CTA) used in polymerization, the dihedral angle between the aromatic ring and the CS3 grouping is 84.20 (10)°. In the crystal, carboxylic acid inversion dimers linked by pairs of O—H...O hydrogen bonds generate R22(8) loops.

In the title compound, C15H15NO, the dihedral angle between the benzene rings is 2.25 (2)°. The C—C—C—O atoms of the propanol side chain are in a gauche conformation [torsion angle = −60.5 (2)°]. In the crystal, O—H...O hydrogen bonds link the molecules into C(2) chains propagating in [100]. The O-bonded H atom is disordered over two sites of equal occupancy.

In the title compound C14H14BrNO3, the coumarin ring system is almost planar (r.m.s. deviation = 0.008 Å) and an intramolecular C—H...O interaction generates an S(6) ring. In the crystal, molecules are linked by N—H...O hydrogen bonds, with the C=O unit of the coumarin ring system acting as the acceptor group, generating [010] C(8) chains. The chain connectivity is reinforced by two C—H...O interactions.

In the title compound, C14H10BrF3O4, the coumarin ring system is almost plannar (r.m.s. deviation = 0.025 Å) and a short C—H...F contact occurs. The propanoate fragment is orientated almost perpendicular to the ring [dihedral angle = 71.80 (12)°]. In the crystal, molecules are linked by C—H...O hydrogen bonds, generating [100] chains.

In the title compound C33H30S6, the three pendant methylene benzodithioate groups lie to one side of the central benzene ring in a cis-cis-cis `tripod' arrangement. The dihedral angles between the central benzene ring and the three pendant rings are 72.54 (4), 89.68 (4) and 86.74 (4)°. In the crystal structure, one of the benzene rings is disordered over two orientations in a 0.559 (13):0.441 (13) ratio.

In this work, we describe the use of hydridosilanes for the attachment of polymer monolayers to SiO2surfaces. In one approach, first a benzophenone group containing hydridosilane is self-assembled on the SiO2surface followed by photochemical attachment of polymer chains deposited onto the monolayer. In a second approach an ATRP initiator is self-assembled to the substrate surface, again using hydridosilane anchor groups. The surface-attached initiator groups are subsequently used for the growth of surface-attached polymer chains in a surface-initiated polymerization reaction. It is shown that, while chlorosilanes require rather stringent exclusion of moisture during self-assembly, the hydridosilanes are rather robust and functional monolayers are formed even under ambient conditions. That in turn allows for the use of silanes in standard printing processes. In contrast to printing of chlorosilanes, which must be carried out under strictly anhydrous conditions, printing of hydridosilanes thus represents a simple and versatile technique for the generation of microstructured surfaces. [ABSTRACT FROM AUTHOR]

Well defined graft copolymers are prepared by “grafting from” atom transfer radical polymerization (ATRP) at room temperature (30 °C). The experiments were aimed at grafting methacrylates and styrene at latent initiating sites of polystyrene. For this purpose, the benzylic hydrogen in polystyrene was subjected to allylic bromination with N‐bromosuccinimide and azobisisobutrylnitirle to generate tertiary bromide ATRP initiating sites (Br—C—PS). The use of Br—C—PS with lesser mol % of bromide initiating groups results in better control and successful graft copolymerization. This was used to synthesize a series of new graft copolymers such as PS‐g‐PBnMA, PS‐g‐PBMA, PS‐g‐GMA, and PS‐g‐(PMMA‐b‐PtBA) catalyzed by CuBr/PMDETA system, in bulk, at room temperature. The polymers are characterized by GPC, NMR, FTIR, TEM, and TGA. Graft copolymerization followed by block polymerization enabled the synthesis of highly branched polymer brush, in which the grafting density can be adjusted by appropriate choice of bromide concentration in the polystyrene. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3818–3832, 2007 [ABSTRACT FROM AUTHOR]

Type 2 diabetes mellitus (T2DM), responsible for most diabetes cases recorded worldwide, increases the risk of chronic wounds and amputation. Patients with T2DM appear to be more susceptible to delayed wound healing due to their treatment adherence. This review explores the specifics of polypharmacy, side effects, possible drug interactions and the importance of medication adherence for therapeutic efficacy. We discuss the effects of anti-diabetes medications on wound healing as well as the role that biofilms and microbial infections play in diabetic wounds. Inconsistent use of medications can lead to poor glycaemic control, which negatively affects the healing process of diabetic foot ulcers. Managing chronic wounds represents a substantial portion of healthcare expenditures. Biofilm-associated infections are difficult for the immune system to treat and respond inconsistently to antibiotics as these infections are slow growing and persistent. Additionally, we emphasize the critical role pharmacists play in enhancing patient adherence and optimizing diabetes treatment by offering comprehensive coverage of drugs associated with problems related to pharmacological therapy in type 2 diabetes.

The preparation of soilless medium for the growth of seeds based on macroporous scaffolds of chitosan-glutaric acid and urea (CHGAUR) is reported. The CHGAUR scaffold was prepared by the hydrothermal reaction of chitosan with GA in presence of urea. The product was purified using Soxhlet extraction with methanol. CHGAUR was composed of chitosan with a small weight fraction of glutaric acid and urea, which were present in the salt form as confirmed by TGA and FT IR spectroscopy. This suggested that CH is most likely to be physically crosslinked in the scaffold through GAUR links. SEM images confirmed the porous structure of material. Water absorption studies suggested that CHGAUR could absorb ∼4100-5700 % water and could be varied by varying the CH: UR ratio used in the preparation. The percentage porosity of CHGAUR did not vary much with urea content suggesting that significant variation in the micropore structure was not obtained by varying the urea content in the preparation. Mechanical tests revealed that material was soft and flexible and able to retain its original shape even after removing the load. CHGAUR, in purified state, was studied for the germination and seedling growth. Among the seeds investigated, pigeon pea showed the best result., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Chitosan (CH)-guar gum (GG) composite films crosslinked with tannic acid (TnA) were prepared by solution casting method. The films were then immersed in 5 % aqueous NH 3 and dried again. They were characterized by IR spectroscopy, wide angle x-ray diffraction and thermogravimetric analysis. All the films were studied for physicochemical properties such as moisture content, swelling, solubility in water, water contact angle, water vapor permeability, opacity, tensile strength and antioxidant activity. The physicochemical and mechanical properties of films changed significantly when compared to CH as reflected by an increase in the amorphous domains of the films, a decrease in moisture content, swelling and solubility in water. The films turned hydrophobic with concomitant decrease in moisture content, swelling, water-solubility and exhibited improved UV absorption as well as mechanical strength, which in turn was dependent on the tannic acid concentration. These results along with enhanced antioxidant properties, UV absorption with no significant change in water vapor permeation compared to CH suggested that the films could find application in packaging applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Poly(butylene adipate-co-terephthalate) (PBAT), a compostable polymer, filled with different weight percentage of unbleached nano chitin (NC; 10%, 30% and 50%), a biodegradable filler from crustacean waste, were prepared from the extruded blends by injection moulding and 3D printing. The nanochitin required was prepared from chitin isolated from prawn shells (Fenneropenaeus indicus). The nanochitin crystals were observed to contain carboxylic acid surface functional groups as assessed by FT-IR, 13 C solid state NMR (SS NMR) spectroscopy, zeta potential measurements and the extent of the same was estimated by potentiometric titration. The PBAT-NC nanocomposites were characterized SS NMR spectroscopy, FT-IR spectroscopy, wide angle X-ray diffraction, dynamic mechanical analysis, DSC and TGA. Thermal and mechanical properties of the nanocomposites were determined. The moulded nanocomposites changed more and more rigid with increasing weight percentage of NC without significant change in the tensile strength. The TGA indicated that the thermal stability of PBAT could be improved but not significantly by the addition of NC. Wound healing was enhanced in the presence of the nanocomposite while in vivo toxicity was significant at high concentration. The PBAT-NC nanocomposites could be moulded in to useful articles such as laptop charger cover, rat cover for washing machine, planters and key holders under conditions similar to that used in the processing of LDPE., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Biocompatible hydrogels were prepared by mixing aqueous-acidic solution of chitosan with alkali lignin, a major by-product of the paper producing industries, for the first time, by sustainable means. Electrostatic interactions between the phenoxide groups in lignin and the ammonium groups on the chitosan backbone were found to be responsible for the ionotropic cross-linking. These gels were non-toxic to Mesenchymal stem cells, in vitro, and to zebrafish up to 100 μg/ml, in vivo. In addition, these gels provided a conducive surface for cell attachment and proliferation, making it suitable for application as scaffolds in tissue engineering. In presence of the hydrogel, NIH 3T3 mouse fibroblast cells showed good cell migration characteristics suggesting that the gel might be suitable for wound healing application. The chitosan-alkali lignin gelation system was further capable of removing ferric ions from contaminated water by way of complexation and coagulation. Cross-linked films of chitosan and alkali lignin could also be prepared by simply immersing chitosan films into a solution of alkali lignin. Alkali lignin was observed to diffuse into the chitosan "crystal", forming electrostatic cross-links between the chitosan chains. The choice of lignin, in comparison to the other ionotropic cross-linkers for chitosan, makes the cross-linking system, inexpensive and sustainable., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A novel method of preparing chitosan gels using in situ generated negatively-charged colloidal salts of a variety of metal ions is described. Their potential as scaffolds for tissue-engineering and as recoverable catalysts in aza-Michael addition is demonstrated here. Given their wide range of properties, they have broad scope for applications.

The preparation of porous films (average size variation from 1 to 32 μm) of a 1:1 blend of chitosan with poly(EG- ran -PG) by the controlled evaporation of water from a 2 wt % aqueous acetic acid solution is reported. Interestingly, the blend exhibited porosity that could be tailored from 1 to 32 μm with the temperature of preparation of the blend film. The powder X-ray diffraction, Fourier transform infrared, and differential scanning calorimetry analyses of the films suggested the formation of partially miscible blends. Temperature-induced phase separation of the blend appears to be the mechanism of pore formation. The tensile strength, cytotoxicity, and biocompatibility of the blend films for the growth of mesenchymal stem cells were assessed vis-a-vis chitosan. The 1:1 blend film was observed to lack cytotoxicity and was also viable for the growth of mesenchymal stem cells. The tensile properties of the 1:1 blend were superior to those of the chitosan film. The simple preparation of porous, nontoxic, and biocompatible films could find use as a scaffold in the growth of tissue, and especially bone tissue, in wound dressing, and in filtration if a better control over pore size is achieved., Competing Interests: The authors declare no competing financial interest.

Four new novel donor-acceptor (A-π-D-A, A-D-π-D-A) compounds (1 a, 1 b, 2 a and 2 b) based on ethylenedioxythiophene (EDOT) and phenothiazine (PTz) have been rationally designed and synthesized towards solid state emission ranging from yellow to near infrared (NIR). The compounds 1 b and 2 b, in thin film form, showed an emission maximum at 713 nm and 696 nm, respectively, with the corresponding absolute solid-state quantum yield of 3.3 % and 9.0 %. The fluorophores showed high emission in the doped state as well when dispersed in polystyrene (PS) matrix with emission maximum ranging from 536 nm to 648 nm with quantum yield in the range 12.4 %-64.4 %. The presence of dicyanovinyl (DCV) group in both the fluorophores was exploited towards cyanide sensing in DMSO leading to turn-on fluorescence emission with high selectivity and sensitivity for cyanide ion with a detection limit of as low as 0.32 μm (8 ppb) for 1 b and 0.57 μm (14 ppb) for 2 b. DFT and TTDFT calculations suggested that the addition of cyanide ion prevented the intramolecular charge transfer (ICT) from the donor (PTz or EDOT) to acceptor (DCV), thereby turning the fluorescence "On". Using fluorescent spectral and color switching, we have explored logic gates with single and two input signal amplification by applying chemical and light inputs in the form of CN - ion and UV., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new superabsorbent with maximum water absorption capacity of ∼1250 g/g is prepared by hydrothermal synthesis from sustainable and biodegradable resources such as chitosan, citric acid and urea (denoted as 'CHCAUR'). CHCAUR is characterized extensively by various analytical techniques such as PXRD, SSNMR, FTIR, and TGA. Pure and saline water absorption study showed that CHCAUR could be a better adsorbent compared to the super absorbent polymer (SAP) used in commercial diaper material. The mechanism of water absorption is shown to arise out of a combination of electrostatic attraction of water to the ionic crosslinks and the presence of macropores as well as undulated surface due to the formation of nanofibrous bundles. When applied to soil CHCAUR was found to decrease water evaporation rate significantly., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

A new, simple, green method for the synthesis of Au nanowires (average diameter 8 nm and several micrometers in length) using Au seeds prepared from bael gum (BG) is reported. The nanowires are characterized using UV-visible absorption spectroscopy, powder X-ray diffraction, transmission electron microscopy (TEM), and high-resolution-TEM. It is observed that the rate of the reduction process might be the decisive factor for the shape selectivity, as evident from the formation of nanowires at a particular concentration of seeds and NaOH. The polysaccharide present in BG is the active ingredient for the synthesis of Au nanowires, while the small molecules present in BG, when used alone, did not result in nanowire formation. The TEM images of the precursor to the Au nanowires suggested that new, nucleated particles align in a linear manner and fuse with one another, resulting in the nanowire. The linear fusion of the newly nucleated particles could be due to the lack of adequate protecting agent and the presence of Au complex adsorbed to the surface. The electrochemical activity of the nanowires for oxygen reduction reaction (ORR) is assessed and compared with that of nanotriangles and spherical nanoparticles of Au. The performance of Au nanowire is better than Au-nanomaterials (heat-treated as well as non-heat-treated), Au seeds, and clusters. The better efficiency of the nanowires when compared to that of the other reported catalysts is attributed to the presence of active (100) facets with numerous corners, edges, and surface defects.

A new, super water-absorbing, material is synthesized by the reaction between chitosan, EDTA and urea and named as CHEDUR. CHEDUR is probably formed through the crosslinking of chitosan molecules (CH) with the EDTA-urea (EDUR) adduct that is formed during the reaction. CHEDUR as well as the other products formed in control reactions are characterized extensively. CHEDUR exhibits a very high water uptake capacity when compared with chitosan, chitosan-EDTA adduct, as well as a commercial diaper material. A systematic study was done to find the optimum composition as well as reaction conditions for maximum water absorbing capacity. CHEDUR can play a vital role in applications that demand the rapid absorption and slow release of water such as agriculture, as a three in one new material for the slow release of urea, water and other metal ions that can be attached through the EDTA component. The other potential advantage of CHEDUR is that it can be expected to degrade in soil based on its chitosan backbone. The new material with rapid and high water uptake could also find potential applications as biodegradable active ingredient of the diaper material., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Corynebacterium jeddahense sp. nov., strain JCB(T), is the type strain of Corynebacterium jeddahense sp. nov., a new species within the genus Corynebacterium. This strain, whose genome is described here, was isolated from fecal flora of a 24-year-old Saudi male suffering from morbid obesity. Corynebacterium jeddahense is a Gram-positive, facultative anaerobic, nonsporulating bacillus. Here, we describe the features of this bacterium, together with the complete genome sequencing and annotation, and compare it to other member of the genus Corynebacterium. The 2,472,125 bp-long genome (1 chromosome but not plasmid) contains 2,359 protein-coding and 53 RNA genes, including 1 rRNA operon.

Hepatoprotective activity of methanolic extract of Syzygium jambos (Alston) (Linn.) leaves against Paracetamol-induced hepatic damage in Wistar albino rats was observed at two different doses, 100 and 200 mg/kg body weight. The healthy control, disease control, and standard drug Silymarin-treated groups were also maintained for the comparison. The liver marker enzymes SGOT, SGPT, ALKP, Serum Bilirubin and other metabolic parameters like total cholesterol, HDL-cholesterol were evaluated in all the experimental groups. The changes in liver function parameters were significant in comparison to disease control group and the observed efficacy was comparable to standard drug. The efficacy of the extract was found to be dose dependent. The histopathology study of liver also supports the presence of hepatoprotective activity in S. jambos by showing improved cytoarchitecture of liver cells in the treated groups. The results obtained in this study indicate necessity for further research on isolation and characterization of functional molecules from the extract.

The inter-conversion of 3-phosphoglycerate and 2-phosphoglycerate during glycolysis and gluconeogenesis in filarial nematodes, is catalyzed by a co-factor-independent phosphoglycerate mutase (iPGM). The gene encoding iPGM isoform-1 was amplified from Wuchereria bancrofti, the major causative agent of human lymphatic filariasis. Partial genomic DNA (gDNA) fragment of the gene was also amplified from periodic and sub-periodic forms of W. bancrofti and Brugia malayi and sequenced. The Wb-iPGM isoform-1 gene encodes an ORF of 515 amino acids and is found to share 99.4%, 96.0%, and 64.0% amino acid sequence identity with iPGM of B. malayi, Onchocerca volvulus, and Caenorhabditis elegans, respectively. Serine and all the other 13 amino acid residues involved in the catalytic function of iPGM are highly conserved. Further comparison of iPGM nucleotide and amino acid sequences of Wolbachia of B. malayi with Wb-iPGM showed 41% and 54.4% similarity, respectively. The analysis of partial genomic and amino acid sequences and phylogenetic tree of Wb-iPGM indicated that this gene, apart from being a potential drug target, could provide diagnostic, taxonomical, and evolutionary markers. This is the first report of the characterization of iPGM gene from W. bancrofti., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The mol-ecular structure of the title compound, C(14)H(18)Br(2)N(2)O(2), has one half-mol-ecule in the asymmetric unit. The mol-ecule has a crystallographic inversion centre in the middle of the benzene ring. The C-C-N-C torsion angle between the benzene ring and the bromo-amide group is 149.2 (7)°. The crystal is stabilized by a strong inter-molecular N-H⋯O bond and weak C-H⋯O inter-actions. These contacts give rise to a three-dimensional network.

In the title compound, C(12)H(14)O(2)S(3), a chain transfer agent (CTA) used in polymerization, the dihedral angle between the aromatic ring and the CS(3) grouping is 84.20 (10)°. In the crystal, carb-oxy-lic acid inversion dimers linked by pairs of O-H⋯O hydrogen bonds generate R(2) (2)(8) loops.

We demonstrate, for the first time, the synthesis of model poly(benzyl methacrylate) [P(BnMA)] brushes of very high thickness (>300 nm) on silicon wafer. P(BnMA) brush is also synthesized from the surface of silica nanoparticles, from a covalently anchored initiator monolayer, using ambient temperature ATRP. The kinetic studies and block copolymerization from the surface anchored P(BnMA)-Br macroinitiator showed that the polymerization was controlled in nature. AFM, ellipsometry, and water contact angle were used for the characterization of the polymer brush. The grafting density of the P(BnMA) brush, formed by immersion in a dilute monomer solution, was relatively less (∼11% less) in comparison to that obtained by immersion in neat monomer under similar conditions. The P(BnMA)-Br macroinitiator brushes were used to synthesize P(BnMA-b-S) diblock copolymer brushes by the ATRP of styrene at 95 °C. The P(BnMA-b-S) brushes showed stimulus response to a selective solvent and various nanopatterns were observed according to the composition of the block copolymer.

Background: Periplasmic serine proteases of HtrA type of Wolbachia have been shown to play a role in the pathogenesis of filarial disease., Aims: This study was aimed to sequence Wb-HtrA serine protease and analyze its phylogenetic position by comparing with other filarial and non-filarial nematode homologs., Materials and Methods: Partial HtrA gene fragment was amplified from DNA isolated from periodic and sub-periodic Wuchereria bancrofti parasites collected from Pondicherry and Nicobar islands, respectively. The amplicons were sequenced, and sequence homology and phylogenetic relationship with other filarial and non-filarial nematodes were analyzed., Results: Partial orthologue of HtrA-type serine protease from Wolbachia of W. bancrofti was amplified, cloned and sequenced. The deduced amino acid sequence exhibited 87%, 81% and 74% identity with the homologous Wolbachia proteases identified from Brugia malayi, Onchocerca volvulus and Drosophila melanogaster, respectively. The Wb-HtrA has arthologues in several proteobacteria with very high homology and hence is highly conserved not only among Wolbachia of filarial parasites but also across proteobacteria. The phylogenetic tree constructed using Neighbor-Joining method showed two main clusters: cluster-I containing bacteria that dwell in diverse habitats such as soil, fresh and marine waters and plants and cluster-II comprising Anaplasma sp. and Erlichia, and Wolbachia endosymbionts of insects and nematodes, in distinct groups., Conclusions: HtrA-type serine protease from Wolbachia of W. bancrofti is highly conserved among filarial parasites. It will be of interest to know whether filarial Wolbachia HtrA type of serine protease might influence apoptosis and lymphatic epithelium, thereby playing a role in the filarial pathogenesis. Such information will be useful for identifying targets for the development of newer drugs for filariasis treatment, especially for preventing lymphatic pathology.

Wuchereria bancrofti, a nematode parasite, is responsible for causing 90% of lymphatic filariasis infection in the world. In India, W. bancrofti exists in two physiological forms, nocturnally periodic in the main land and diurnally sub-periodic in Car Nicobar group of islands. Differentiation of these two parasitic forms by conventional microscopic methods difficult requiring good skill and hence tedious. Therefore, we developed a simple and rapid Random Amplified Polymorphic DNA (RAPD) assay to differentiate these parasitic forms. Also, the phylogenetic relationship between periodic and sub-periodic W. bancrofti and also Brugia malayi populations was analyzed using RAPD profile generated. Distinct RAPD profiles were observed among the three parasites with the formation of three distinct clusters in the phylogenetic tree. Substantial genetic diversity (Nei's genetic diversity H) was observed among periodic (H = 0.0577) and sub-periodic (H = 0.1415) W. bancrofti populations.

In the title compound, C(15)H(15)NO, the dihedral angle between the benzene rings is 2.25 (2)°. The C-C-C-O atoms of the propanol side chain are in a gauche conformation [torsion angle = -60.5 (2)°]. In the crystal, O-H⋯O hydrogen bonds link the mol-ecules into C(2) chains propagating in [100]. The O-bonded H atom is disordered over two sites of equal occupancy.

In the title compound C(14)H(14)BrNO(3), the coumarin ring system is almost planar (r.m.s. deviation = 0.008 Å) and an intra-molecular C-H⋯O inter-action generates an S(6) ring. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, with the C=O unit of the coumarin ring system acting as the acceptor group, generating [010] C(8) chains. The chain connectivity is reinforced by two C-H⋯O inter-actions.

In the title compound, C(14)H(10)BrF(3)O(4), the coumarin ring system is almost plannar (r.m.s. deviation = 0.025 Å) and a short C-H⋯F contact occurs. The propano-ate fragment is orientated almost perpendicular to the ring [dihedral angle = 71.80 (12)°]. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, generating [100] chains.