Crystallographic investigation, Hirshfeld surface analysis, NLO characterization and experimental spectral (UV and NMR) studies with DFT probe on(R)-9-(2-hydroxy propyl)adenine.

In this study, (R)-9-(2-hydroxy propyl)adenine (HPA) is the molecule of interest for investigation. The XRD from single crystal of HPA has been used to extract its structural features. Since HPA crystallised in a non-centro symmetric space group P212121, its NLO property was studied and it was found to exhibit very good SHG activity. To explore the intermolecular interactions the generated Hirshfeld surface has been investigated along with 2D-fingerprint plots. The experimental electronic and NMR spectra taken in the UV-visible and radio frequency regions respectively for HPA have been corroborated in correlation with theoretical predictions at Density Function Theory using 6-311++g (d, p) basis set. The experimental XRD geometrical parameters, chemical shifts of 13C and 1H and λmax values of HPA fit satisfactorily with the corresponding theoretically obtained numerical values as well as the stimulated spectrograms with the experimental ones. Further to explore the electronic structure, the MESP surface has been generated and investigated. The thermodynamic, kinetic and chemical reactivity features have been explored by means of frontier molecular orbitals of HPA.

Crystallographic, spectral and computational studies on (S)-4-(4-aminobenzyl) oxazolidin-2-one.

The experimental geometry (XRD), vibrational (IR and Raman), electronic (UV-visible) and NMR spectra of (S)-4-(4-Amino-benzyl)-oxazolidin-2-one (ABO) have been corroborated with the corresponding first principle calculated values at DFT using hybrid B3LYP exchange correlation functional invoking 6-311++g(d, p) basis set. The optimized geometrical parameters were found to be in satisfactory agreement with the experimental values obtained from the X-ray diffraction structural features of ABO. The scaled down computed vibrational frequencies with appropriate scaling factors were in good correspondence with the experimental observations. Room-temperature 1H and 13C nuclear magnetic resonance (NMR) studies were supported by advanced density functional theory calculations. The theoretical spectrograms of FT-IR, FT-Raman, 1H NMR, 13C NMR and UV of the title compound have been constructed and compared with experimental spectra and Hirshfeld surface analysis has also been made to study the intermolecular interactions. The electronic structure of the title compound has also been studied in terms of HOMO, LUMO and MESP diagrams.

Maternal exposure to alkali, alkali earth, transition and other metals: Concentrations and predictors of exposure.

Most studies of metals exposure focus on the heavy metals. There are many other metals (the transition, alkali and alkaline earth metals in particular) in common use in electronics, defense industries, emitted via combustion and which are naturally present in the environment, that have received limited attention in terms of human exposure. We analysed samples of whole blood (172), urine (173) and drinking water (172) for antimony, beryllium, bismuth, cesium, gallium, rubidium, silver, strontium, thallium, thorium and vanadium using ICPMS. In general most metals concentrations were low and below the analytical limit of detection with some high concentrations observed. Few factors examined in regression models were shown to influence biological metals concentrations and explained little of the variation. Further study is required to establish the source of metals exposures at the high end of the ranges of concentrations measured and the potential for any adverse health impacts in children.

Insulin on hydrogen peroxide-induced oxidative stress involves ROS/Ca2+ and Akt/Bcl-2 signaling pathways.

Oxidative stress is induced by excess accumulation of reactive oxygen and nitrogen species (RONS). Astrocytes are metabolically active cells in the brain and understanding astrocytic responses to oxidative stress is essential to understand brain pathologies. In addition to direct oxidative stress, exogenous hydrogen peroxide (H2O2) can penetrate biological membranes and enhance formation of other RONS. The present study was carried out to examine the role of insulin in H2O2-induced oxidative stress in rat astrocytic cells. To measure changes in the viability of astrocytes at different concentrations of H2O2 for 3 h, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT)-based assay was used and 500 µM H2O2 was selected to establish a model of H2O2-induced oxidative stress. Further assays showed that 3 h of 500 µM H2O2-induced significant changes in the levels of lactate dehydrogenase (LDH), reactive oxygen species (ROS) and calcium ion (Ca(2+)) in C6 cells, with insulin able to effectively diminish H2O2-induced oxidative damage to C6 cells. Western blotting studies showed that insulin treatment of astrocytes increased the levels of phosphorylated Akt and magnified the decrease in total Bcl-2 protein. The protective effect of insulin treatment on H2O2-induced oxidative stress in astrocytes by reducing apoptosis may relate to the PI3K/Akt pathway.

Maternal exposure to metals--concentrations and predictors of exposure.

A variety of metals are important for biological function but have also been shown to impact health at elevated concentrations, whereas others have no known biological function. Pregnant women are a vulnerable population and measures to reduce exposure in this group are important. We undertook a study of maternal exposure to the metals, aluminium, arsenic, copper, cobalt, chromium, lithium, manganese, nickel, selenium, tin, uranium and zinc in 173 participants across Western Australia. Each participant provided a whole blood and urine sample, as well as drinking water, residential soil and dust samples and completed a questionnaire. In general the concentrations of metals in all samples were low with the notable exception of uranium (blood U mean 0.07 µg/L, range <0.01-0.25 µg/L; urinary U mean 0.018 µg/g creatinine, range <0.01-0.199 µg/g creatinine). Factors that influenced biological concentrations were consumption of fish which increased urinary arsenic concentrations, hobbies (including mechanics and welding) which increased blood manganese concentrations and iron/folic acid supplement use which was associated with decreased concentrations of aluminium and nickel in urine and manganese in blood. Environmental concentrations of aluminium, copper and lithium were found to influence biological concentrations, but this was not the case for other environmental metals concentrations. Further work is underway to explore the influence of diet on biological metals concentrations in more detail. The high concentrations of uranium require further investigation.

Cadmium, lead and mercury exposure in non smoking pregnant women.

Recent literature suggests that exposure to low concentrations of heavy metals may affect both maternal and child health. This study aimed to determine the biological heavy metals concentrations of pregnant women as well as environmental and dietary factors that may influence exposure concentrations. One hundred and seventy three pregnant women were recruited from Western Australia, each providing a sample of blood, first morning void urine, residential soil, dust and drinking water samples. Participants also completed a questionnaire which included a food frequency component. All biological and environmental samples were analysed for heavy metals using ICP-MS. Biological and environmental concentrations of lead and mercury were generally low (Median Pb Drinking Water (DW) 0.04 µg/L; Pb soil <3.0 µg/g; Pb dust 16.5 µg/g; Pb blood 3.67 µg/L; Pb urine 0.55; µg/L Hg DW <0.03; Hg soil <1.0 µg/g; Hg dust <1.0 µg/g; Hg blood 0.46 µg/L; Hg urine <0.40 µg/L). Cadmium concentrations were low in environmental samples (Median CdDW 0.02 µg/L; Cdsoil <0.30 ug/g; Cddust <0.30) but elevated in urine samples (Median 0.55 µg/L, creatinine corrected 0.70 µg/g (range <0.2-7.06 µg/g creatinine) compared with other studies of pregnant women. Predictors of increased biological metals concentrations in regression models for blood cadmium were residing in the Great Southern region of Western Australia and not using iron/folic acid supplements and for urinary cadmium was having lower household annual income. However, these factors explained little of the variation in respective biological metals concentrations. The importance of establishing factors that influence low human exposure concentrations is becoming critical in efforts to reduce exposures and hence the potential for adverse health effects.

Molecular structure, vibrational spectroscopic, first order hyperpolarizability and HOMO-LUMO studies of 7-amino-8-oxo-3-vinyl-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid.

The FT-IR and FT-Raman spectra of 7-amino-8-oxo-3-vinyl-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid (7AVCA) were recorded in the region 4000-400 cm(-1) and 3500-10 cm(-1), respectively. Quantum chemical calculations of energies, geometrical structure and vibrational wavenumbers were carried out by ab initio HF and density functional theoretical methods invoking 6-311G(d,p) basis set. The differences between the observed and scaled wavenumber values of most of the fundamentals are very small. The electric dipole moment (µ) and the first order hyperpolarizability (ß0) values have been computed quantum mechanically. The calculated results show that 7AVCA may have microscopic nonlinear optical (NLO) behavior with non-zero values. A detailed interpretation of the FT-IR and FT-Raman spectra of 7AVCA is reported. The theoretical IR and Raman spectra of 7AVCA have also been constructed. The calculated HOMO and LUMO energies show that the charge transfer occurs within the molecule.

FT-IR, FT-Raman, ab initio and DFT structural and vibrational frequency analysis of 6-aminopenicillanic acid.

Quantum mechanical calculations of energies, geometries and vibrational wavenumbers of 6-aminopenicillanic acid were carried out by using ab initio HF and density functional theory (DFT/B3LYP) methods with 6-311G(d,p) basis set. The optimized geometrical parameters obtained by HF and DFT calculations are in good agreement with experimental X-ray data. A detailed interpretation of the infrared spectra has also been reported. The theoretical IR and Raman spectrograms have been constructed and compared with the experimental FT-IR and FT-Raman spectra. The differences between the observed and scaled wavenumber values of most of the fundamentals are very small. The thermodynamic parameters have also been computed.

FT-IR and FT-Raman vibrational assignment of 2-bromobenzoic acid with the help of ab initio and DFT calculations.

The vibrational spectra of 2-bromobenzoic acid (2BBA) have been experimentally recorded (FT-IR and FT-Raman) and compared with the harmonic vibrational frequencies calculated at HF and B3LYP level of theories using 6-311+G(d,p) basis set with appropriate scaling factors. The XRD geometrical parameters show satisfactory agreement with the theoretical prediction at Hartree-Fock and B3LYP levels. The scaled vibrational frequencies at B3LYP/6-311+G(d,p) seem to coincide with the experimentally observed values with acceptable deviations. The theoretical spectrograms (IR and Raman) have been constructed and compared with the experimental FT-IR and FT-Raman spectra.

Vibrational spectroscopic studies and DFT calculations of 4-aminoantipyrine.

The pyrazole derivative, 4-aminoantipyrine (4AAP), used as an intermediate for the synthesis of pharmaceuticals especially antipyretic and analgesic drugs has been analyzed experimentally and theoretically for its vibrational frequencies. The FTIR and FT Raman spectra of the title compound have been compared with the theoretically computed frequencies invoking the standard 6-311g(d,p) and cc-pVDZ basis sets at DFT level of theory (B3LYP). The harmonic vibrational frequencies at B3LYP/cc-pVDZ after appropriate scaling method seem to coincide satisfactorily with the experimental observations rather than B3LYP/6-311g(d,p) results. The theoretical spectrograms for FT-IR and FT-Raman spectra of 4AAP have been also constructed and compared with the experimental spectra. Additionally, thermodynamic data have also been calculated and discussed.

Molecular structure and vibrational spectra of 3-amino-5-hydroxypyrazole by density functional method.

In this work, we report a combined experimental and theoretical study on molecular and vibrational structure of 3-amino-5-hydroxypyrazole (3A5HP). The Fourier transform infrared and Fourier transform Raman spectra of 3A5HP were recorded in the solid phase. The molecular geometry and vibrational frequencies of 3A5HP in the ground state have been calculated by using the density functional method B3LYP with basis sets, 6-311++G(d,p), 6-311+G(3df,2p), 6-311+G(3df,2pd), CC-pVDZ, aug-CC-pVDZ and CC-pVTZ. The optimized geometrical parameters obtained by B3LYP show best agreement with the experimental values. The theoretical spectrograms for FT-IR and FT-Raman spectra of the title molecule have been constructed.

Harmonic analysis of vibrations of morpholine-4-ylmethylthiourea: a DFT, midinfrared and Raman spectral study.

The FTIR and FT-Raman spectra of morpholine-4-ylmethylthiourea (MMTU) were recorded in the region of mid-IR (400-4,000 cm(-1)). Initial geometry generated from the standard geometrical parameters was relaxed without any constraint on the potential energy surface at MP2 and DFT levels adopting the standard 6-31++G and 6-311+G basis set. With the help of two specific scaling procedures the computed harmonic frequencies have been compared with the observed vibrational wave numbers of FTIR and FT-Raman spectra and assigned to different normal modes of the molecule. Most of the vibrational modes have wave numbers in the expected range. The appropriate theoretical spectrograms of the IR spectra of MMTU have been also constructed.

Experimental (FTIR and FT-Raman) and ab initio and DFT study of vibrational frequencies of 5-amino-2-nitrobenzoic acid.

The FTIR and FT-Raman spectra of 5-amino-2-nitrobenzoic acid (ANB) have been recorded in the region 400-4000 cm(-1). The observed frequencies were assigned to different modes of vibrations on the basis of fundamental, combination and overtones. The geometry has been optimized with complete relaxation on the potential energy surface at HF, MP2 and B3LYP level of theories using 6-311++G(d,p) basis set and compared with the crystal data. The possible hydrogen bond interaction has been estimated taking a model compound. Further harmonic vibrational frequency calculations have been carried out at HF and B3LYP levels and the scaled values were in good agreement with majority of the experimental observations. The theoretically constructed spectra coincide satisfactorily with those of experimental spectra.

Design and in vitro testing of a floatable gastroretentive tablet of metformin hydrochloride.

Metformin hydrochloride, which is better absorbed in the upper intestine, was formulated as a floating (buoyant) matrix tablet using a gas generating agent (sodium bicarbonate) and a gel forming hydrophilic polymer (hydroxypropyl methylcellulose). The formulation was optimized on the basis of floating ability and in vitro drug release. The resulting formulation produced robust tablets with optimum hardness, consistent weight uniformity and low tablet friability. All tablets but one exhibited satisfactory (gradual and near complete) drug release and buoyancy. In vitro drug release tests of these tablets indicated controlled sustained release of metformin hydrochloride and 96-99% released at the end of 8 h. Two formulations of fabricated tablets containing metformin hydrochloride (500 mg), sodium bicarbonate (75 mg), hydroxypropyl methylcellulose-K 4M (170-180 mg), citric acid (between 15 and 20 mg) and polyvinyl pyrrolidone K90 (32-40 mg) with hardness between 6.8 to 7.5 kg/cm2 showed a floating time of more than 8 h and promising drug release results. The release followed the Higuchi kinetic model, indicating diffusion dominated drug release.

Laparoscopic repair of ureterovaginal fistula: successful outcome by laparoscopic ureteral reimplantation.

We describe our technique of laparoscopic repair of ureterovaginal fistula in a 34-year-old woman who developed a vaginal leak of urine 15 days after laparoscopic hysterectomy. Laparoscopy and extravesical ureteral reimplantation with a stent was carried out. Cystoscopy and stent removal was done after 6 weeks. The patient was dry. To our knowledge, laparoscopy for the repair of ureterovaginal fistula has not been described. This distressing condition can be corrected laparoscopically with obvious benefit to the patient.

FTIR, FT-Raman spectra and ab initio DFT vibrational analysis of 2-bromo-4-methyl-phenylamine.

The FTIR and FT-Raman spectra of 2-bromo-4-methyl-phenylamine (BMP) have been recorded. From the standard geometrical parameters the geometry of BMP was optimized at ab initio and DFT levels of theory with complete relaxation in the potential energy surface using 6-311+g(d,p) and 6-311+g(2df,2p) basis sets. Several thermodynamic parameters were also calculated for the minimum energy conformer at ab initio and DFT level of theories. The harmonic vibrational frequencies were calculated and the scaled values have been compared with experimental FTIR and FT-Raman spectra. Majority of the computed wavenumbers were found to be in good agreement with the experimental observations. The experimental spectra also coincide satisfactorily with those of theoretically constructed bar type spectrograms.

Comparison of topical itraconazole 1% with topical natamycin 5% for the treatment of filamentous fungal keratitis.

PURPOSE: To compare the clinical efficacy of itraconazole 1% eyedrops with a standard therapy regimen (natamycin 5% eyedrops) for topical monotherapy of fungal keratitis. METHODS: Patients presenting with suspected uniocular microbial keratitis over a period of 12 months (January to December 2002) underwent detailed clinical examination and microbiological investigation. One hundred consecutive patients with direct smear- and/or culture-proven fungal keratitis were enrolled in the study after obtaining informed consent. The ulcers were categorized as severe or nonsevere. The first 50 consecutive patients received primary therapy with topical natamycin hourly, and the next 50 consecutive patients received topical itraconazole hourly. The primary efficacy criteria were the physician's judgment of clinical success, cure rate, and the rate of treatment failure. RESULTS: The diagnosis of fungal keratitis was established by positive microscopy and culture findings in 88 patients and by positive microscopy alone in 12 patients. Species of Fusarium, Aspergillus, and Curvularia were the principal isolates. Thirty-six (72%) of 50 patients (28 of 37 with nonsevere keratitis and 8 of 13 with severe keratitis) showed a favorable response to primary natamycin therapy (mean duration, 20.5 days), while 30 (60%) of 150 patients (25 of 38 with nonsevere keratitis and 5 of 12 with severe keratitis) exhibited a favorable response to primary itraconazole therapy (mean duration, 23.1 days). In keratitis due to Fusarium spp, 19 (79%) of 24 patients showed a favorable response to natamycin, which was significantly greater than the 8 (44%) of 18 patients who showed a favorable response to itraconazole (P < 0.02). However, no such difference was evident in keratitis due to Aspergillus spp or Curvularia spp; in keratitis due to Aspergillus spp, favorable responses were noted in 6 (54.5%) of 11 patients receiving natamycin and 5 (50%) of 10 patients receiving itraconazole, while in keratitis due to Curvurlaria spp, such responses occurred in both patients receiving natamycin and in 8 (89%) of 9 patients receiving itraconazole. Both antifungal formulations were generally well tolerated with no obvious adverse effects. CONCLUSIONS: Topical natamycin should continue to be considered as the treatment of choice for filamentous fungal keratitis; when natamycin is unavailable, topical itraconazole therapy could be used, particularly if the infections are due to Aspergillus or Curvularia spp.

FT-Raman and FTIR spectra, assignments and ab initio calculations of 2-aminobenzyl alcohol.

The Fourier transform Raman and Fourier transform infrared spectra of 2-aminobenzyl alcohol (2ABA) were recorded in the solid phase. Geometry optimizations were done with out any constraint and harmonic vibrational wave numbers and several thermodynamic parameters were calculated for the minimum energy conformer at ab initio and DFT levels invoking 6-31g** and 6-311+g(2d, p) basis sets and the results were compared with the experimental values. With the help of three specific scaling procedures, the observed vibrational wavenumbers in FTIR and FT-Raman spectra were analyzed and assigned to different normal modes of the molecule. Most of the modes have wavenumbers in the expected range and the error obtained was in general very low. The appropriate theoretical spectrograms for the Raman and IR spectra of 2ABA were also constructed.

Keratitis due to a coelomycetous fungus: case reports and review of the literature.

PURPOSE: To describe a series of 7 patients with ulcerative keratitis caused by species of Colletotrichum, which are coelomycetous fungal pathogens. METHODS: The patients presented with keratitis of varying degrees of severity. Multiple scrapes from the corneal lesions of 6 of the 7 patients were used for microbiological investigations by a standard protocol. In the seventh patient, scraping was not performed due to the presence of deep infiltration and a descemetocele at presentation. All 7 patients were hospitalized and treatment was initiated with topical applications of natamycin (5%) and ciprofloxacin (0.3%) every hour and cyclopentolate (1%) drops 3 times daily. An emergency therapeutic penetrating keratoplasty was performed after 48 hours in the patient who had presented with a descemetocele and for another patient whose keratitis did not respond to 10 days of medical therapy. RESULTS: The corneal samples of all 7 patients yielded significant growth of filamentous fungi in culture. On the basis of macroscopic and microscopic characteristics, the fungal isolates were identified as Colletotrichum spp. Corneal lesions completely resolved with medical therapy alone in 5 patients. In the 2 patients who had undergone therapeutic penetrating keratoplasty, the infection was eradicated and the corneal graft remained clear even after several months of follow-up. CONCLUSION: Colletotrichum spp may be more frequent causes of keratitis than previously thought. Keratitis due to Colletotrichum spp frequently responds to medical therapy alone, although surgery may be indicated in a small proportion of patients.

Laparoscopic transperitoneal repair of retrocaval ureter: report of two cases.

We report our experience in the laparoscopic transperitoneal repair of retrocaval ureter in two cases, highlighting a new technique of stenting.