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The mild and efficient palladium-catalyzed ortho C(sp 2 )-H diversification of (NH)-free 2-substituted benzimidazole, quinazoline, and imidazopyridine is reported using hypervalent iodine as the key reagent. Acetoxy, aryl, iodide and nitro functional groups were introduced on the same substrate by simply shifting the reaction conditions in the presence of inorganic additives (Cs 2 CO 3 , I 2 , NaNO 2 ) and the hypervalent iodine reagent (diacetoxyiodo)benzene (PIDA) under aerobic conditions. The combination of NaNO 2 with PIDA was successfully employed in Pd-catalyzed C-H bond nitration to achieve a library of nitrated 1,3 N-heterocycles. This versatile ortho C(sp 2 )-H activation strategy features operational simplicity, short reaction times, and ample substrate possibilities, it requires no ligands or silver salts as additives, and it shows good tolerance of oxidation prone functional groups.

Background: Cognitive training is beneficial in various clinical settings, although its perioperative feasibility and impact remain unknown. The objective of this pilot study was to determine the feasibility of home-based cognitive prehabilitation before major surgery in older adults., Materials and Methods: Sixty-one patients were enrolled, randomized, and allocated to either a home-based preoperative cognitive training regimen or no training before surgery. Outcomes included postoperative delirium incidence (primary outcome; assessed with the 3D-Confusion Assessment Method), perioperative cognitive function based on NIH Toolbox measures, hospital length of stay, and physical therapy session participation. Reasons for declining enrollment were reported, as were reasons for opting out of the training program., Results: Postoperative delirium incidence was 6 of 23 (26%) in the prehabilitation group compared with 5 of 29 (17%) in the control group (P=0.507). There were no significant differences between groups in NIH Toolbox cognitive function scoring, hospital length of stay, or physical therapy participation rates. Study feasibility data were also collected and reported. The most common reasons for declining enrollment were lack of computer access (n=19), time commitment (n=9), and feeling overwhelmed (n=9). In the training group, only 5 of 29 (17%) included patients were able to complete the prescribed 7 days of training, and 14 of 29 (48%) opted out of training once home. Most common reasons were feeling overwhelmed (n=4) and computer difficulties (n=3)., Conclusions: Short-term, home-based cognitive training before surgery is unlikely to be feasible for many older patients. Barriers to training include feeling overwhelmed, technical issues with training, and preoperative time commitment.

Aims: Our earlier studies revealed the cardio-protective effects of oleic acid, a monounsaturated fatty acid, against adrenaline induced myocardial injury. Moreover, it has been found to possess antioxidant properties. Thus, in the present study we have investigated the protective role of oleic acid on adrenaline induced mitochondrial dysfunction in vitro in rat heart mitochondria., Main Methods: Isolated rat cardiac mitochondria was incubated in vitro with adrenaline-bitartrate alone and with graded doses of oleic acid. Biomarkers of oxidative stress, mitochondrial Krebs cycle enzymes and respiratory chain enzymes along with mitochondrial morphology, membrane potential as well as intactness were analyzed. Isothermal titration calorimetric studies with pure adrenaline and oleic acid was also carried out., Key Findings: Incubation with adrenaline, in vitro, showed elevated levels of lipid peroxidation and protein carbonylation of mitochondrial membrane, a reduced level of glutathione content along with an altered profile of mitochondrial enzymes, morphology, membrane potential as well as intactness. All these changes were found to be ameliorated when cardiac mitochondria were co-incubated with adrenaline and oleic acid, in vitro., Significance: Our earlier studies demonstrated the antioxidant properties of oleic acid. This study suggests that oleic acid binds adrenaline with high affinity gradual saturation of the binding sites of adrenaline. This prevents the generation of ROS and finally providing consequent protection of the cardiac mitochondria and ameliorating adrenaline induced mitochondrial dysfunction. Hence, oleic acid may be considered as a potent future cardio-protective antioxidant., (Copyright © 2018 Elsevier Inc. All rights reserved.)

We have evaluated the LDH inhibitory property of novel pyrazolo[4',3':5,6][1,4]oxathiino[2,3-b]pyrazine derivatives which have been synthesized from easily available starting materials through a one-pot protocol that offers the use of elemental sulfur as the sulfur source. These newly synthesized compounds may aid to drug development for neoplastic and non-neoplastic diseases characterized by increased glucose metabolism. Additionally, they may act as suitable starting materials which can be further structurally modified for the development of new LDH inhibitors with higher efficacy and specificity., Competing Interests: The authors declare that they have no conflict of interest., (© Georg Thieme Verlag KG Stuttgart · New York.)

A one-flask thioetherification of pyrazolones has been demonstrated by transforming several pyrazolones to their corresponding 4-mercaptopyrazolone derivatives and employing them towards cross-coupling with various aromatic and heteroaromatic iodides by applying Pd(OAc) 2 /xantphos as the catalytic system. The coupling ability of these thiol intermediates with 2,3-dichloropyrazine through an aromatic S N 2 pathway has also been established. This methodology provides the use of inexpensive starting materials along with a short reaction time.

A catalyst-free green methodology for the synthesis of pharmacologically important spirooxindole derivatives has been developed by a three-component domino reaction between isatin, various amino compounds, and 1,3-dicarbonyl or 3-phenylisoxazolone compounds in ethyl L-lactate medium at room temperature. This new efficient synthetic method facilitated the formation of a wide range of biologically significant spirooxindole derivatives (including 17 new spirooxindoles) under very mild conditions. The cytotoxic activity of one of the isoxazole-fused spirooxindoles was evaluated in MDA-MB 468 breast cancer cell line. It was found that cell survivability decreases with increasing concentration of the selected compound in MDA-MB 468 breast cancer cells.

A robust intramolecular cyclopropanation reaction was first performed on pyranopyrazole and pyranopyrimidine-dione derivatives to obtain spirocyclopropylpyrazolones and barbiturates, using iodosylbenzene (PhIO) or the combination of iodobenzene diacetate (PIDA)/molecular iodine (I 2 ), under mild reaction conditions. Syntheses of functionally and stereochemically diversified, novel spiropyrazolone fused 2-iminothiophene and spiropyrazolone fused pyrroline scaffolds were also demonstrated via Lewis acid catalyzed highly diastereoselective (3 + 2) cycloaddition reactions of the synthesized spiro-cyclopropyl pyrazolones with phenyl isothiocyanate and benzonitrile, respectively.

The aim of this study was to characterize 3 wild culinary-medicinal mushrooms using molecular tools and to analyze their antioxidant activity. Antioxidant properties were studied by evaluating free radical scavenging, reducing power, and chelating effect. The mushrooms were identified as Lentinus squarrosulus, L. tuber-regium, and Macrocybe gigantean by amplifying internal transcribed spacer regions of ribosomal DNA. The results demonstrated that the methanolic extract of M. gigantean has the highest free radical scavenging effect and chelating effect, whereas the methanolic extract of L. squarrosulus has the highest reducing power. The highest total phenol content and the most ascorbic acid were found in the M. gigantean extracts. Among the 3 mushroom extracts, M. gigantean displayed the most potent antioxidant activity. Molecular characterization using the nuclear ribosomal internal transcribed spacer region as a universal DNA marker was an effective tool in the identification and phylogenetic analysis of the studied mushrooms. The study also indicated that these wild macrofungi are rich sources of natural antioxidants.

An advanced protocol for the diastereoselective intramolecular aziridination reaction has been developed to synthesize 2-oxa-7-azabicyclo[4.1.0]hept-3-en-1-yl carboxylates from their corresponding 4-H-pyrans and spiropyrans analogues employing iodosylbenznene as the exclusive oxidant in the presence of carboxylic acid and triethylamine. High structural and stereochemical diversity of these pyran fused NH-azridine scaffolds makes them useful in evaluating their biological and pharmacological activities by SAR studies. Additionally, their potential synthetic application has been uncovered by efficient transformation into biologically relevant novel pyranooxazolone and pyrrole derivatives.

A Probabilistic Neural Network (PNN) is a statistical algorithm and consists of a grouping of multi-class data. The conventional method of detection of DNA mutations by the human eye may not detect the minute variations in PCR-SSCP bands, which may lead to false positive or false negative results. The detection by photographic images may contain a blare (noise) caused during the time of photography; therefore, image processing techniques were used to reduce image noise. PCR-SSCP gels of T2DM patients (n = 100) and controls (n = 100) were initially photographed with equal ratio of pixels and later subjected to a two-stage analysis: feature extraction and PNN. The evaluation of the results was done by quality training and the accuracy was up to 95%, and the human eye analysis showed 80% mutation detection rate. This study proves to be very reliable and gives accurate and fast detection for mutation analysis in diabetes. This method could be extended for analysis in other human diseases.

An ecofriendly, one-pot, three component ZnO nanoparticles-mediated synthesis of 4H-chromene in water under thermal condition has been described. The highly product-selective three component electrophilic reaction of 2-hydroxybenzaldehyde with an active methylene compound and another carbon-based varied nature of nucleophile has been developed by a reversible alkylation procedure using greener "NOSE" approach. Greenness of the process was well instituted, as water was used both as reaction media as well as medium for the synthesis of catalyst. In these reactions, the use of nano-ZnO as a catalyst was documented to be crucial for rendering the reactions possible in water media, while replacing nano-ZnO with other acids or bases resulted in the generation of too many side products. The catalyst can be efficiently recycled up to the sixth run, an essential point in the area of green chemistry. The methodology provides cleaner conversion, shorter reaction times, and high selectivity, which make the protocol globally putative. The crystal structures of 4H-chromene, easily produced by a chromatography-free highly product-selective reaction, were explored by means of single crystal X-ray diffraction analysis, and H-bonding arrangements of one signified compound prepared is presented. In optimized mild conditions, the isolated yields are 86-93%.

A green chemical synthesis of silver nanoparticles (AgNPs) through in situ reduction of silver nitrate (AgNO(3)) by a fungal strain of Rhizopus oryzae is described along with the promising eco-friendly role of the synthesized nano-silver bioconjugate (NSBC) material in water purification process. The NSBC has been characterized using UV-vis spectroscopy, high resolution transmission electron (HRTEM) microscopy, and Fourier transform infrared (FTIR) spectroscopy. The NSBC exhibits strong antibacterial activity against Escherichia coli and Bacillus subtilis and high adsorption capacity towards different organophosphorous pesticides. Fluorescence and electron microscopic images reveal NSBC binds on the bacterial cell wall, which cause irreversible membrane damage eventually leading to cell death. Proteomic analysis further demonstrates down regulation of protein expression, inhibition of cytosolic and membrane proteins and leakage of cellular content following binding of NSBC with bacterial cell wall. NSBC has been exploited to obtain potable water free from pathogens and pesticides in one step process., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Interfacial and bulk properties of sodium dodecyl sulfate (SDS), polyoxyethylene (20) sorbitan monooleate (Tween-80), and their binary mixtures in aqueous medium have been investigated using surface tension, conductance, and fluorescence measurements at different temperatures. The critical micelle concentration (CMC), counterion binding, polarity index, aggregation number, thermodynamics of interfacial adsorption, and micellization are evaluated. The entropic contribution is found to be the predominant factor in micelle formation. The aggregation number and the polarity index of the micelle interior estimated by the pyrene fluorescence technique show interesting temperature dependence. The size and composition of the mixed micelles vary with the total concentration. The micellar compositions, activities of the individual components in the mixed species, and intersurfactant interactions are also estimated following regular solution theory, excess thermodynamic functions, and a molecular thermodynamic model. The surfactant mixtures are found to be nonideal with a lower degree of counterion binding compared to the individual members. Mixed micelles are nonspherical in nature at all temperatures when the mole fraction (α) of the ionic part in mixtures is high but transform to spherical when α(SDS) is ≤0.50., (© 2011 American Chemical Society)

The morbidity and mortality in a cohort of 452 children followed up from birth up to 3 years of age, in an urban slum in India, is described. These children were recruited and followed from March 2002 to September 2006. A prospective morbidity survey was established. There were 1162 child-years of follow-up. The average morbidity rate was 11.26 episodes/child-year. Respiratory infections caused 58.3 and diarrheal disease 18.4% of the illnesses. Respiratory illnesses resulted in 48, 67.5 and 50 days of illnesses, and there were 3.6, 1.64 and 1.16 diarrheal episodes per child in the 3 years, respectively. There were five deaths in the cohort in the 3 years of follow-up. Of the 77 drop-outs 44 were contacted for mortality data. The morbidity in the area is high, comparable to other studies. The mortality is low, and is attributed to the facilitated access to care.

The development of methodologies for the synthesis of nanoparticles of well-defined size and shape is a challenging one and constitutes an important area of research in nanotechnology. This Full Paper describes the controlled synthesis of multishaped gold nanoparticles at room temperature utilizing a simple, green chemical method by the interaction of chloroauric acid (HAuCl4 x 3H20) and cell-free extract of the fungal strain Rhizopus oryzae. The cell-free extract functions as a reducing, shape-directing, as well as stabilizing, agent. Different shapes of gold nanocrystals, for example, triangular, hexagonal, pentagonal, spherical, spheroidal, urchinlike, two-dimensional nanowires, and nanorods, are generated by manipulating key growth parameters, such as gold ion concentration, solution pH, and reaction time. The synthesized nanostructures are characterized by UV/Vis and Fourier-transform infrared spectroscopy, transmission electron microscopy, and energy dispersive X-ray analysis studies. Electron diffraction patterns reveal the crystalline nature of the nanoparticles and a probable mechanism is proposed for the formation of the different structural entities.

The interaction of hexadecyltrimethylammonium bromide (HTAB) and methylcellulose (MC) has been investigated in aqueous medium employing rheological and fluorescence probing experiments. The associated physicochemical properties of the polymer-surfactant mixed system such as critical aggregation concentration (cac), critical micelle concentration (cmc), micellar aggregation number (N), micellar micropolarity index (pyrene I(1)/I(3) values), and viscosity curve are studied as a function of HTAB concentration. The effects of sodium benzoate (NaBz), sodium hexanoate (NaHx) and sodium chloride (NaCl) on the behavior of the polymer-surfactant solution have been followed systematically. The obtained experimental findings unfold significant information with respect to the effects of the salts on the solution behavior of the mixed system in addition to gelation characteristics.

Objectives: To determine health care provider cost and household cost of the treatment of severe pneumonia in infants and young children admitted to secondary and tertiary level health care facilities., Methods: The study was done in a private, not-for-profit medical college hospital, in Vellore, India, in mid-2008. Children aged 2-36 months admitted with severe pneumonia with no underlying chronic disease were included in the study. The relatives were interviewed daily on matters relating to patients' view point of the costs. These were direct medical costs, direct non-medical costs which comprised travel, accommodation and special food during the period of illness, and indirect costs of productivity loss for family members. Patient specific resource consumption and related charges were recorded from charts, nursing records, pharmacy lists and hospital bills, and the providers view point of the costs was estimated. Unit cost estimates for bed days, treatment and investigation inputs were calculated., Results: Total cost to health care provider for one episode of hospitalized childhood pneumonia treated at secondary level was US$ 83.89 (INR 3524) and US$ 146.59 (INR 6158) at tertiary level. At both levels the greatest single cost was the hospital stay itself, comprising 74% and 56% of the total cost, respectively. Diagnostic investigations were a large expense and supportive treatment with nebulization and oxygen therapy added to the costs. Mean household expenditure on secondary level was US$ 41.35 (INR 1737) and at tertiary level was US$ 134.62 (INR 5655), the largest single expense being medicines in the former and the hospitalization in the latter. (one US$=INR 42.1 at time of study), Conclusions: A considerable cost difference exists between secondary and tertiary level treatment. Admission at lowest possible treatment level for appropriate patients could decrease the costs borne by the provider and the patient.

A green chemical method to synthesize nanogold-bioconjugate and its eco-friendly promising role to purify contaminated waters has been described. Gold nanoparticles of 10 nm average diameter are produced on the surface of Rhizopus oryzae , a fungal strain, by in situ reduction of chloroauric acid (HAuCl(4)). The nanogold-bioconjugate (NGBC) showed strong adsorption capacity toward different organophosphorous pesticides. The EDXA study confirms adsorption of pesticides on the conjugate material surface. Morphological changes of the NGBC material after adsorption of organophosphorous pesticides were detected by atomic force micrographs. NGBC shows high antimicrobial activity against several Gram-negative and Gram-positive pathogenic bacteria as well as the yeasts Saccharomyces cerevisiae and Candida albicans . The treatment of microbial cells with NGBC caused rupture of cell membrane as revealed in scanning electron and fluorescence micrographs. These unique characteristics of NGBC have been successfully utilized to obtain potable water free from pathogens and pesticides in a single operation.

For establishment of the structure-activity relationship, 19 heterobicycle-coumarin conjugated compounds with the -SCH(2)- linker were synthesized and found to possess significant antiviral activities. Prominent examples included imidazopyridine-coumarin 12c, purine-coumarin 12d, and benzoxazole-coumarin 14c, which inhibited HCV replication at an EC(50) of 6.8, 2.0, and 12 microM, respectively. The heteroatoms in bicycles and the substituent effect on coumarin played essential roles.

Alterations of cell surface properties accompanying the complex life cycle of Termitomyces clypeatus have been monitored using atomic force microscopy (AFM). A new hyphae/mycelium is developed on cell division, and the cell wall of the mycelium undergoes a process of internal reorganization (or maturation) followed by morphological and chemical alterations. The changes of the surface ultrastructures during the growth process are correlated to the corresponding changes in relative viscoelasticity and rigidity of the cell wall by employing force spectroscopy. The cell wall rigidity and elasticity are found to be 0.34+/-0.02 N/m and 27.5+/-2.1 MPa, respectively, at the early logarithmic phase, on maturation increase to reach 0.81+/-0.08 N/m and 92.5+/-12 MPa, respectively, at the stationary phase, and thereafter decrease to 0.62+/-0.06 N/m and 61.6+/-6.6 MPa at the death phase. The alterations of the ultrastructural and nanomechanical properties of the cell surface as functions of growth phases affect the interaction involving chromium and T. clypeatus.

The adsorption characteristics of mercury on Aspergillus versicolor mycelia have been studied under varied environments. The mycelia are functionalized by carbon disulfide (CS(2)) treatment under alkaline conditions to examine the enhance uptake capacity and explore its potentiality in pollution control management. The functionalized A. versicolor mycelia have been characterized by scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDXA), attenuated total reflection infrared (ATR-IR), and atomic force microscopy (AFM) probing. SEM and AFM images exhibit the formation of nanoparticles on the mycelial surface. ATR-IR profile confirms the functionalization of the mycelia following chemical treatment. ATR-IR and EDXA results demonstrate the binding of the sulfur groups of the functionalized mycelia to the mercury and consequent formation metal sulfide. AFM study reveals that the mycelial surface is covered by a layer of densely packed domain like structures. Sectional analysis yields significant increase in average roughness (R(rms)) value (20.5 +/- 1.82 nm) compared to that of the pristine mycelia (4.56 +/- 0.82 nm). Surface rigidity (0.88 +/- 0.06 N/m) and elasticity (92.6 +/- 10.2 MPa) obtained from a force distance curve using finite element modeling are found to increase significantly with respect to the corresponding values of (0.65 +/- 0.05 N/m and 32.8 +/- 4.5 MPa) of the nonfunctionalized mycelia. The maximum mercury adsorption capacity of the functionalized mycelia is observed to be 256.5 mg/g in comparison to 80.71 mg/g for the pristine mycelia.

Mixed micelle formation and interfacial properties of aqueous binary and ternary combinations of hexadecyltrimethylammonium bromide (C(16)Br), hexadecylbenzyldimethylammonium chloride (C(16)BzCl) and polyoxyethylene (20) cetyl ether (Brij58) at 25 degrees C in 30 mM aqueous NaCl have been studied in detail employing tensiometric and fluorimetric techniques. The micellar and adsorption characteristics like composition, activity coefficients, mutual interaction parameters and free energy of micellization have been estimated using the theoretical approaches of Clint, Rosen, Rubingh, Blankschtein et al., Rubingh-Holland and Maeda. A comprehensive account of the comparative performance of these models on the selected cationic-cationic-nonionic surfactant mixtures at constant ionic strength has been presented. The Blankschtein model predicted lower synergism than from Rubingh's method because it neglects the contribution due to steric interaction between surfactant head groups of different sizes and charges. Free energy of micellization calculated using Maeda's approach, which employs interaction parameter and micellar mole fraction from Rubingh's model as inputs, shows good correlation with that calculated from commonly used phase separation model. The present study also reveals that the modified Rubingh-Holland method along with the Rosen's model can be applied to analyze the interfacial characteristics of ternary surfactant mixtures with a fair degree of success thereby widening the domain of applicability of this model.

Catanionic microemulsions formed by dodecyltrimethylammonium bromide (DTAB), sodium dodecyl sulfate (SDS), n-hexanol, dodecane, and citrate buffer have been characterized by using dynamic light scattering (DLS) and spectroscopic studies. While the DLS measurements provide information about the hydrodynamic diameters of the microemulsion droplets formed upon variation of the constituents, steady-state and time-resolved fluorescence emission experiments probe the polarity and the dynamics of the trapped solvent pool inside of the microemulsion droplets of nanometer dimension. In addition, time-resolved fluorescence anisotropy shows the rigidity of the confined solvent pool as well as the coupling between the motion of a solute and those of the solvent molecules. The results obtained from the DLS and those from the steady-state and time-resolved fluorescence emission studies have been found to correlate well with the superactivity of horseradish peroxidase enzyme in the catanionic microemulsions. Subsequently, the time-zero estimate for the dynamic Stokes shift in these microemulsions reveals that approximately 50% of the total solvent dynamical response is missed due to the limited time resolution employed in our experiments. The amplitude of the missing portion is similar to what has been observed recently for nanoscopic water by Fayer and co-workers (Piletic, I. R.; Tan, H.-S.; Fayer, M. D. J. Phys. Chem. B 2005, 109, 21273).

Reaction of alkyl, acetoxy, and silyl enol ethers of 3-(organosilyl)cyclohexanone with molecular dioxygen in toluene at 110 degrees C produced the corresponding conjugated enones in yields up to 88% yield. The reaction of the same type failed on replacement of the silyl group at the C-3 position with an isopropyl group. These results indicate the existence of an unprecedented silicon-induced ene-type reaction. Its reaction mechanism, generality, limitations, and exceptions are discussed.

Nineteen new conjugated compounds were successfully synthesized by a one-flask method from benzimidazole and coumarin derivatives. A methylenethio linker was used to connect these two kinds of derivatives. In addition, substituted benzimidazol-2-thiones were also coupled with beta-D-glucose peracetate; the resultant glucosides were further converted to the corresponding 2-(methylthio)coumarin derivatives. Their activity against the hepatitis C virus was tested; two of the most potent compounds 2-[(6'-bromocoumarin-3'-yl)methylenethio]-5-fluorobenzimidazole (4i) and its derivative 1-[(2'',3'',4'',6''-tetra-O-acetyl)glucopyranos-1''-yl]-2-[(6'-bromocoumarin-3'-yl)methylenethio]benzimidazole (7c) showed EC(50) values of 3.4 microM and 4.1 microM, respectively. At a concentration of 5.0 microM, compound 7c inhibited HCV RNA replication by 90% and had no effect on cell proliferation. Given these data, a structure-activity relationship was established.

The adsorption behavior of mercury on Aspergillus versicolor biomass (AVB) has been investigated in aqueous solution to understand the physicochemical process involved and to explore the potentiality of AVB in pollution control management. This biomass has been successfully used for reducing the mercury concentration level in the effluent of chloralkali and battery industries to a permissible limit. The results establish that 75.6 mg of mercury is adsorbed per gram of biomass. The adsorption process is found to be a function of pH of the solution, with the optimum range being pH 5.0-6.0. The process obeys the Langmuir-Freundlich isotherm model. Scanning electron microscopic analysis demonstrates a conspicuous surface morphology change of the mercury-adsorbed biomass. A nearly uniform distribution of metal ions on the mycelial surface excepting a few aggregation points is revealed by X-ray elemental mapping profiles. The results of zeta potential measurement, Fourier transform infrared (FTIR) spectroscopy, and blocking of the functional groups by chemical modification reflect the binding of mercury on the biomass occurs through electrostatic and complexation reactions. The accumulation of mercury on the cell wall associated with negligible diffusion and or transportation into cytoplasm finds support from the results of adsorption kinetics and transmission electron micrographs. Mercury adsorption on biomass also leads to elongation of cells and cytoplasmic aggregation of spheroplast/protoplasts, indicating that the cell wall acts as a permeation barrier against this toxic metal.

Water solubility enhancements of polycyclic aromatic hydrocarbons (PAHs), viz., naphthalene, anthracene and pyrene, by micellar solutions at 25 degrees C using two series of surfactants, each involving two cationic and one nonionic surfactant in their single as well as equimolar binary and ternary mixed states, were measured and compared. The first series was composed of three surfactants, benzylhexadecyldimethylammonium chloride (C16BzCl), hexadecyltrimethylammonium bromide (C16Br), and polyoxyethylene(20)mono-n-hexadecyl ether (Brij-58) with a 16-carbon (C16) hydrophobic chain; the second series consisted of dodecyltrimethylammonium bromide (C12Br), dodecylethyldimethylammonium bromide (C12EBr), and polyoxyethylene(4)mono-n-dodecyl ether (Brij-30) with a 12-carbon (C12) chain. Solubilization capacity has been quantified in terms of the molar solubilization ratio, the micelle-water partition coefficient, the first stepwise association constant between solubilizate monomer and vacant micelle, and the average number of solubilizate molecules per micelle, determined employing spectrophoto-, tensio-, and flourimetric techniques. Cationic surfactants exhibited lesser solubilization capacity than nonionics in each series of surfactants with higher efficiency in the C16 series compared to the C12 series. Increase in hydrophobicity of head groups of cationics by incorporation of ethyl or benzyl groups enhanced their solubilization capacity. The mixing effect of surfactants on mixed micelle formation and solubilization efficiency has been discussed in light of the regular solution approximation (RSA). Cationic-nonionic binary combinations showed better solubilization capacity than pure cationics, nonionics, or cationic-cationic mixtures, which, in general, showed increase with increased hydrophobicity of PAHs. Equimolar cationic-cationic-nonionic ternary surfactant systems showed lower solubilization efficiency than their binary cationic-nonionic counterparts but higher than cationic-cationic ones. In addition, use of RSA has been extended, with fair success, to predict partition coefficients of ternary surfactant systems using data of binary surfactants systems. Mixed surfactants may improve the performance of surfactant-enhanced remediation of soils and sediments by decreasing the applied surfactant level and thus remediation cost.

Bismuth ammonium citrate complex (C24H20Bi4O28 x 6NH3 x 10H2O) interacted with sodium sulphide (Na2S) in presence of beta-cyclodextrin (beta-CD) yielding Bi2S3 nanospheres. Solvothermal treatment of the bismuth complex and dimethyl sulphoxide (DMSO) produced Bi2S3 nanorods. Reaction conditions were optimized to investigate the morphology evolution of the product. Electrical properties of the nanorods were monitored in details.

The removal of a carcinogenic dye rhodamine B (C. I. 45170) from wastewater by biomass of different moulds and yeasts is described. Among all of the fungal species tested, the biomass of Rhizopus oryzae MTCC 262 is found to be the most effective. Dye adsorption reaches maximum with the biomass harvested from the early stationary phase of growth. The optimum temperature and pH for adsorption are observed to be 40 degrees C and 7.0, respectively. The adsorption rate is very fast initially and attains equilibrium after 5 h. The adsorption isotherm follows the Langmuir isotherm model satisfactorily within the studied dye concentration range. Of the different metabolic inhibitors tested, 2,4-ditrophenol (DNP) and N,N'-dicyclohexylcarbodiimide (DCCD) decrease dye adsorption by approximately 30% suggesting the role of energy metabolism in the process. Spectrophotometric study indicates that the removal of rhodamine B by R. oryzae biomass involves an adsorption process. Scanning (SEM) and transmission (TEM) electron microscopic investigations have been carried out to understand the probable mechanism of the dye-biomass interaction.

Recrystallization of elemental selenium (Se) from aqueous solution in presence of sodium sulphite (Na2SO3) and sodium sulphide (Na2S) acting as complexing agents has resulted in the formation of nano and microstructures of Se having five different morphological modifications. (1) An aqueous solution of sodium selenosulphate (Na2SO3Se) obtained by dissolving Se in Na2SO3 under refluxing condition yields hemispherical microcrystals. (2) The filtrate of the above reaction mixture on aging produces hexagonal prismatic microrods of Se. Addition of Na2SO3Se solution to formalin (HCHO) at room temperature and refluxing conditions generates (3) Se nanorods, and (4) spherical microcrystals, respectively. (5) Recrystallization of Se from aqueous solution of Na2S develops flower shaped microcrystals.

Mixed micelle formation and interfacial properties of aqueous binary surfactant combinations of dodecyltrimethylammonium bromide (C12TAB) and tetraethyleneglycol mono-n-dodecyl ether (C12E4) at 30 degrees C in absence and presence of sodium propionate (NaPr) have been investigated. The critical micelle concentration, aggregation number, micropolarity and interfacial adsorption have been quantitatively estimated by surface tension and steady-state fluorescence measurements. The micellar and adsorption characteristics like composition, activity coefficients and mutual interaction parameters have been estimated following different theoretical treatments like that of Clint, Rubingh, Rodenas, Maeda, Blankschtein and Rosen. The analysis reveals very small mole fraction of cationic surfactant in both the mixed micelles and mixed monolayer inspite of synergism. Blankschtein's model predicts a continuous decrease in synergism due to the salt effect of NaPr; Rubingh's approach, on the contrary, indicates an increase in it above 30 mM of NaPr concentration. Aggregation number variation with NaPr indicates the same. Mixed monolayer shows better synergism compared to that in mixed micelles which increases with the addition of sodium propionate above 30 mM concentration.

A simple solution phase approach is described to prepare tellurium nanorods which undergo morphological modifications to yield different microstructures under varied experimental conditions. The morphology of the prepared products is drastically altered in presence of a few oxidizing agents such as sodium oxychloride (NaOCl), hydrogen peroxide (H2O2) etc. The effects of poly (sodium 4-styrene sulphonate) (PSS) and Isooctyl phenoxy poly oxyethanol (TritonX-100) on the size and shape of the products in presence of air/NaOCl have also been monitored.

The process of sorption is being increasingly used for ecofriendly and economic remediation of textile dye effluents. The present model study deals with the adsorption of a model anionic dye, eosin Y, from wastewater using conditioned chitosan hydrobeads. Conditioning reduced the pH sensitivity and maintained the maximum sorption capacity of the beads near pH 8. To understand the chemicophysical characteristics of the adsorption process we studied, the kinetics and isotherm behavior of the system. It was observed that temperature played a significant role in the process. The Langmuir model was found to be most appropriate for the description of the adsorption process. The kinetic results followed a second-order equation. It was observed that 1 g of chitosan adsorbed approximately 76 mg of eosin Y. The dye was desorbed from the beads by changing the pH of the solution, and the conditioned chitosan beads were reused five times without any loss of mechanical and chemical efficacy.

[reaction: see text]. Symmetric azoxy arenes were successfully prepared in one step from 2 equiv of the corresponding nitroarenes by use of sodium bis(trimethylsilyl)amide as the deoxygenating agents in THF at 150 degrees C in a sealed tube.

This study describes the development of a novel thiocationic (OBEHYTOP) lipid-based formulation of phosphorothioate antisense oligonucleotides (PAOs) showing inhibitory activity against mycobacterium tuberculosis (mTB) as measured by an in vitro BACTEC 460TB assay. PAOs were designed based on sequences complementary to essential regions of the mycobacterial genome from published nucleic acid databases in GenBank. These included the superoxide dismutase sod A gene (TBS3), catalase-peroxidase katG gene (TBK1, TBK10), RNA polymerase beta-subunit rpo B gene (TBR5) and diaminopimelate decarboxylase lys A gene (TBL5). The effect of PAOs (TBS3, K1, K10, R5 and L5) alone on mTB was not significant compared with the no-drug control over a period of exposure of 150 h (ranges of -11.8 to +23.58% at 72 h; 15.26 to +25.82% at 96 h and -5.51 to +24.00% at 150 h). Liposomal formulations (10:5:2 OBEHYTOP:oleic acid:vitamin D3) of PAOs resulted in statistically significant (p < 0.05 in all cases) inhibition (ranges of -51.45 to -63.00% at 72 h; -56.75 to -67.96% at 96 h; -51.45 to -60.26% at 150 h) compared with PAOs alone, thiocationic liposomal control and liposomal components. Positive controls of streptomycin and isoniazid used at their minimum inhibitory concentrations of 2.00 and 0.10 microM, respectively, resulted in average % inhibition values of -94% and -97.36%, respectively, indicating that these thiocationic lipid-formulated PAOs showed inhibitory activity directed against mTB in vitro.

Colloidal dispersions of tungstic acid (H(2)WO(4)) have been prepared in water/(TX-100+alkanol)/n-heptane water-in-oil microemulsion media by reacting Na(2)WO(4) with HCl. The effects of alkanol chain length, TX-100/alkanol mass ratio, temperature, and dilution at different [water]/[TX-100] mole ratios (omega) have been studied by the dynamic light scattering technique. The formation of H(2)WO(4) in the microwater pool has been established by FT-IR measurements. The particle sizes and shapes in microemulsion media and in isolated states have been measured by TEM and SEM techniques. The enthalpy of formation of H(2)WO(4) in the water pool of the microemulsions has also been determined microcalorimetrically. Copyright 2001 Academic Press.

Lung surfactant serves as a protective coating when adsorbed on particle surfaces, so its removal or rate of removal in vivo may affect expression of mineral cytotoxicity. Removal of phospholipid surfactant components from the surface of mineral particles ingested by alveolar macrophages (AM) was measured using fluorescence microscopy. Dipalmitoylphosphatidylcholine with a fluorescent label (BODIPY(trade mark)) substituted for C1-C4 on the second acyl chain (DPPC*), was mixed with dioleoylphosphatidylcholine (DOPC) to coat respirable quartz and kaolin particles. Fluorescence from quartz or kaolin particles of 3-4, 5-6 and 8-9 microm size decreased in intensity with increasing ratios of DOPC/DPPC* for the same DOPC concentration of 0.4 mg/ml. There was a direct correlation between fluorescence and residual phospholipid surfactant remaining on particles using phospholipase A2 (PLA(2)) digestion in a cell-free system, indicating that the presence of the fluorophore on DPPC did not hinder enzymatic recognition. Lavaged primary AM obtained from male Fischer rats were challenged in vitro with DOPC/DPPC* (10:1 mol:mol) coated particles at 50 microg particles/10(6) cells. In contrast to the biexponential response seen in cell-free experiments, the rate of fluorescence decay from ingested coated quartz or kaolin particles over 7 days was monoexponential, with the same t(1/2) (41 h) for each dust. This study suggests that the rate of phagolysosomal digestion and removal of the adsorbed surfactant is not a determinant of the different mineral-specific pathogenicities or toxicities of quartz and kaolin, although residual fluorescence remained on particles even after 7-8 days.

The results of studies on the interaction of binary mixtures of sodium deoxycholate (NaDC) and polyoxyethylene sorbitan monooleate (Tween 80) in bulk and at the air/water interface obtained from conductance, surface tension, and fluorescence measurements are described. The critical micelle concentration (CMC), thermodynamics of micellization, free energy of interfacial adsorption, minimum average area occupied by the surfactant species at the interface, micellar polarity, and aggregation number of the mixed aggregates have been determined. The mixed micellar composition and the estimation of the interacting forces involved are evaluated on the basis of recent theoretical models. The estimated interaction parameter indicates an overall attractive force in the mixed state, and the proportion of NaDC in the mixed micelle is found to be lower compared to the stoichiometric compositions. The mixed aggregates with higher mole fractions of NaDC show less stability in comparison with those having higher proportions of the nonionic component. Copyright 1999 Academic Press.