bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural changes of tissue samples exposed to low frequency electromagnetic field: A FT‐IR absorbance study
Authors: Crupi V. , Interdonato S. , Majolino D. , Mondello M. R. , Pergolizzi S. , Venuti V.
Published: March 2012

In the present work, we report on a preliminary Fourier Transform Infrared (FT‐IR) Absorbance study performed on different kind of rat tissues, such as kidney and heart, exposed to a “non‐ionizing” radiation source at low frequency, in the range typical of micro‐waves (300 MHz < v < 300 GHz). The data were collected in a wide wavenumber region, from 400 cm−1 to 4000 cm−1. The comparison of the absorbance spectra in the case of the normal tissues with the irradiated ones has shown significant differences in the spectral features in accordance with the morphological analysis performed by the optical microscopy.
Patterns of change in cytochrome c oxidase redox status
Authors: Gagnon Roy E. , Macnab Andrew J. , LeBlanc Jacques G.
Published: March 2012

Investigators using mono channel near infrared spectroscopy (NIRS) have reported different patterns of change in cytochrome c oxidase (Cyt) in similar studies of tissue ischaemia. We investigated whether there were distinctive differences in NIRS signals obtained simultaneously from different sampling sites during the same imposed physiological intervention within the same subject. Methods: Subjects were 36, healthy, 10 kg, commercial swine undergoing cardiopulmonary bypass to initiate 3 to 7 periods of 7.5 minutes of circulatory arrest. Each arrest was initiated at one of 81 combinations of high, normal, or low levels of core temperature, haematocrit, pH, and serum glucose. Each combination was repeated twice, yielding 162 NIRS data sets. Results: Six distinct patterns of change of Cyt were found. Typically, brain Cyt quickly became reduced shortly after the start of arrest, muscle Cyt did not start becoming reduced until after 3½ minutes of arrest, and spinal cord Cyt either did not change status or became gradually reduced throughout the period of arrest. The brain response may reflect strong oxygen dependence, while the muscle response may indicate a dependency buffered by myoglobin stores, and the spine response may indicate a low concentration of available Cyt that is too diffuse to be rapidly influenced by changes in oxygen availability. Conclusion: Multi‒channel NIRS is needed for systemic evaluation of respiration at the cellular level in clinical settings. Distinctive Cyt patterns of change occur in different organs at the same time, in response to circulatory arrest.
Preliminary study on the synthesis and high‒resolution NMR analysis of Naproxen and Ibuprofen esters
Authors: Jankowski Christopher K. , LeClair Gaetan , Aumélas André , Gonzalez-de la Parra Mario , Jimenez-Estrada Manuel , Tejada Veronica , Chilpa-Reyes Ricardo , Bélanger Jacqueline M. R. , Paré J. R. Jocelyn
Published: March 2012

The synthesis and NMR analysis of several diastereoisomeric Naproxyl–Naproxenate, Naproxyl–Ibuprofenate and Ibuprofyl–Naproxenate esters are reported. The NMR high resolution spectra run in presence of the chiral shift reagents and variable temperature analysis were done to study the dynamic properties of these esters.
Short‒chain diacyl phosphatidylglycerols: which one to choose for the NMR structural determination of a membrane‒associated peptide from Escherichia coli?
Authors: Wang Guangshun , Keifer Paul A. , Peterkofsky Alan
Published: March 2012

Diacyl phosphatidylglycerols (PG) are the major anionic lipids in the Escherichia coli membrane. Short‒chain dihexanoyl phosphatidylglycerol (DHPG) was previously utilized for the structural determination, by NMR spectroscopy, of the peptide corresponding to the N‐terminal membrane anchor of the glucose‒specific enzyme IIA (IIAGlc) from E. coli. This study explores the possible use of lipid micelles of dioctanoyl phosphatidylglycerol (DOPG) and didecanoyl phosphatidylglycerol (DDPG) as alternatives to DHPG. At a peptide concentration of 1 mM, the minimum peptide/lipid molar ratios required for the formation of the lipid‒binding amphipathic helix are approximately 1 :40, 1 :5, and 1 :5 for DHPG, DOPG, and DDPG, respectively. Based on the lipid titration, the critical micelle concentration (CMC) of DHPG was estimated to be ~50 mM. The 1H spectral linewidths of the peptide bound to a variety of lipid micelles decrease in the following order: DDPG > DOPG > DHPG. The helical regions of the peptide in different anionic lipids were elucidated based on chemical shift indexes (CSI). Residues Leu2‒Leu9, Leu2‒Val10, and Leu2‒Val10 were found to be helical in DHPG, DOPG, and DDPG, respectively, indicating that the lipid chain length had only a subtle effect on the amphipathic helix of the peptide. In light of the minimum peptide/lipid ratio and the spectral linewidth, and the CSI‒derived peptide structure, DOPG is proposed as a good compromise for structural studies of this membrane‒associated peptide by solution NMR spectroscopy.
Spin pH and SH probes: enhancing functionality of EPR‐based techniques
Authors: Khramtsov Valery V. , Grigor’ev Igor A. , Lurie David J. , Foster Margaret A. , Zweier Jay L. , Kuppusamy Periannan
Published: March 2012

Along with significant progress in low‐frequency electron spin resonance (ESR, also called electron paramagnetic resonance, EPR), other techniques such as Longitudinally‐Detected ESR (LODESR), proton electron double‐resonance imaging (PEDRI) and field‐cycled dynamic nuclear polarization (FC‐DNP) have been developed for in vivo applications. However their potential is still far from maximally defined, in part, because of the need for new specific function‐directed spin probes. An application of stable nitroxides of imidazoline and imidazolidine types provides unique possibility to measure local values of pH and thiol content in various biological systems, including in vivo studies. These applications are based on the observation of specific chemical reactions of these nitroxides with protons or thiols, followed by significant changes in their EPR spectra. To increase sensitivity of pH probes for low‐frequency EPR spectroscopy we evaluated two alternative approaches: (i) application of isotopically substituted labels, and (ii) acquisition of EPR spectra at high modulation amplitude. Spatial and spectral‐spatial imaging (pH‐mapping) using PEDRI and L‐band EPR imagers were performed both on phantom samples and in vivo. The applications of the pH and SH probes in model systems, biological fluids, and in vivo in living animals are discussed.
Amyloid fibril formation by bovine cytochrome c
Authors: de Groot Natalia S. , Ventura Salvador
Published: March 2012

Bovine heart cytochrome c is an all‐a globular protein containing a covalently bound heme group. Prolonged incubation at 75°C in mild alkaline solution damages the prosthetic group and results in permanent unfolding of the polypeptide chain. Under this conditions, cytochrome c aggregates into fibrillar structures. Characterization by transmission electron microscopy and thioflavin‐T binding assays shows that these species posses the characteristics of fibrils associated with the family of amyloid diseases. Our findings indicate that destabilization of the native fold of this highly a‐helical protein can lead to its polymerization into ß‐sheet rich structures and suggest that this process does not depend on the population of partially folded monomeric states with extensive ß‐sheet structure.
Calibration and standardisation of synchrotron radiation and conventional circular dichroism spectrometers. Part 2: Factors affecting magnitude and wavelength
Authors: Miles Andrew J. , Wien Frank , Lees Jonathan G. , Wallace B.A.
Published: March 2012

Circular dichroism (CD) spectroscopy is an important tool in structural biology, especially for protein secondary structure analyses. Synchrotron radiation circular dichroism (SRCD) spectroscopy is a modified version of the technique that uses the intense light from a synchrotron source to enable the collection of data to much lower wavelengths than possible on conventional circular dichroism (cCD) instruments. There is a need for standardization of calibration methods amongst and between cCD and SRCD instruments to ensure consistency and the ability to use common reference databases for empirical secondary structural analyses. In a previous study (Spectroscopy17 (2003), 653–661), we compared optical rotation measurements on several cCD and SRCD instruments, whilst holding constant other experimental factors. In this study, other experimental parameters which contribute to the spectral magnitude, such as cell pathlength and protein concentration determinations, are examined. In addition, the extent of wavelength calibration variations between instruments and their effects on secondary structure calculations have been examined. Hence, this paper provides additional practical guidance for “good practice” in the measurement of CD data.
Clinical application of in vivo proton (1H) MR spectroscopy in musculoskeletal tumors
Authors: Wang Chien-Kuo , Hsieh Tsyh-Jyi , Jaw Twei-Shiun , Lin Jau-Nan , Liu Gin-Chung , Li Chun-Wei
Published: March 2012

A technique called in vivo magnetic resonance spectroscopy (MRS) can be performed along with magnetic resonance imaging (MRI) to obtain information about the chemical content of musculoskeletal lesions. This information can be used for several clinical applications, such as improving the accuracy of lesion diagnosis and monitoring the response to cancer therapies. Initial MRS studies of musculoskeletal tumors show promising results, and the technique has been incorporating into the MRI routine protocols. This article introduces 1H MRS of the musculoskeletal tumors, reviews the literature, discusses current methods and technical issues, and describes applications for treatment monitoring and lesion diagnosis.
Site‒specific IR spectroscopy and molecular modelling combined towards solving transmembrane protein structure
Authors: Kukol Andreas
Published: March 2012

Membrane protein structures are underrepresented in structural databases despite their abundance and biomedical importance. This review focuses on the novel method of site‐specific infrared dichroism (SSID) combined with constraint molecular dynamics simulation, which has recently emerged as a powerful method to obtain structures of transmembrane α‐helical bundles. The theory of SSID including its latest developments is reviewed with the aim to encourage widespread application of this method. This is followed by an outline of the conformational search using experimentally constraint molecular dynamics simulations. Finally a critical evaluation of recent applications, namely the Influenza M2 proton channel, the vpu ion channel of HIV‐1 and the MHC‐class II associated invariant chain, is conducted.
Radical induced damage of Micrococcus luteus bacteria monitored using FT‒IR spectroscopy
Authors: Lorin–Latxague Chrystelle , Melin Anne–Marie
Published: March 2012

Oxidative damage induced by ascorbic acid (AA) and hydrogen peroxide (H2O2) was monitored by Fourier transform infrared spectroscopy (FT‒IR); it appeared as a rapid and convenient means to follow the biochemical changes generated in the culture media of the yellow‐pigmented Micrococcus luteus. Beyond a threshold of 20 mM for AA and of 40 mM for H2O2 (final concentration), antioxidant systems were overwhelmed and significant changes were observed in the bacterial spectra, particularly in the 1430–900 cm−1 region; this spectral window provided large information about carboxylate groups, phosphate‐carrying compounds and polysaccharides implicated in the radical process. The spectroscopic results indicated that for the same final concentration, the toxicity of H2O2 was less important than that of AA toward M. luteus cells, although H2O2 had a more damaging effect on proteins. Thus, FT‐IR spectroscopy was an appropriate physico‐chemical tool suitable in biochemical and clinical research for early characterization of any type of radical aggression, and for rapid detection of the damage intensity.
Fluorescence spectroscopy of normal and follicular cancer samples from human thyroid
Authors: Giubileo G. , Colao F. , Puiu A. , Panzironi G. , Brizzi F. , Rocchini P.
Published: March 2012

An autofluorescence analysis has been performed on healthy as well as tumour thyroid tissue samples to distinguish follicular cancer from normal thyroid. Complete spectra and synchronous spectra have been recordered from properly stored samples. Fluorescence bands located at 350 nm and 400 nm has been observed in the analysed cancer samples.
Phantom testing of two clinical spatially‐resolved NIRS instruments
Authors: Macnab A. J. , Gagnon R. E.
Published: March 2012

We used a living biological phantom to evaluate whether previously observed clinical differences in data collection between two similar near infrared spectrophotometers were due to technical design differences. A Somanetics INVOS‐5100 was compared to a Hamamatsu NIRO‐300. Both express the ratio of oxygenated hemoglobin to total hemoglobin concentration as a percentage, and both are intended for monitoring cerebral oxygenation status at the bedside. The living phantom simulated different bone densities and contained a low haematocrit solution of blood, intra‐lipid, and saline, to which was added grower′s yeast to alter oxygenation status. Results: In all trials, oxygen saturation decreased from 100% to 0 % as the yeast consumed the available oxygen. In all trials the spectrometers were significantly correlated (range: r2=0.815 to 0.995, p2>0.232). The NIRO‐300 indicated oxygenation change 1 minute after addition of yeast, whereas the INVOS‐5100 showed change after 5 minutes. Simulated bone thickness had almost no effect upon the NIRO‐300, but did affect the INVOS‐5100. Conclusion: In this study, the spectrophotometers had similar results consistent with the technical design differences: the INVOS‐5100 does not report hemoglobin saturation change above 95% or below 15% while the NIRO‐300 reports the full range from 100% to 0%.
Isotopomer distribution computation from tandem mass spectrometric data with overlapping fragment spectra
Authors: Rousu Juho , Rantanen Ari , Ketola Raimo A. , Kokkonen Juha T.
Published: March 2012

We present a method for determination of the isotopomer distributions of metabolites from the data generated by a tandem mass spectrometer. The method is an improvement over existing method as it is able to deal with overlapping fragments in the spectra. Our experiments indicate that the new method surpasses its predecessors in separating isotopomers from each other. When using the daughter ion scanning (collision induced dissociation) mode, the method was shown to be able to constrain the isotopomer distribution of different amino acids better than two existing methods. In particular, the isotopomer distributions of three amino acids, glycine, alanine and serine, can be fully uncovered with the method. However, due to the imperfect fragmentation of molecules in the tandem mass spectrometer, isotopomer distributions of larger amino acids still cannot be fully uncovered. In tests with isotope‐labelled alanine, most accurate results were obtained using multiple reaction monitoring and 15 eV collision energy. The meausured isotopomer frequecies were in the range 99?106% of the theoretical value and the deviation between repetitions was in the range 1?10%.
Pfg NMR studies of lateral diffusion in oriented lipid bilayers
Authors: Orädd Greger , Lindblom Göran
Published: March 2012

The pfg‐NMR diffusion technique is proposed to have an appreciable potential for future biophysical investigations in the field of membrane biology. Topics like transport of molecules both across and in the plane of the membrane can be successfully studied, as well as the formation of lipid domains and their intrinsic dynamics can be scrutinized. This short review will introduce the fundamental aspects of orientation dependent NMR interactions and the technique of macroscopically oriented bilayers for eliminating the unwanted effects of those interactions. The pfg‐NMR technique will be briefly introduced and finally, some recent results illustrating the potential of the method are presented.
A 13C NMR study of the interactions of Ag13CN and Ag(CN)2– with thiomalic acid, L‐methionine and DL‐selenomethionine
Authors: Isab Anvarhusein A. , Wazeer Mohamed I. M.
Published: March 2012

Complexation of Ag+ as AgNO3, solid AgCN and Ag(CN)2– by labeled and unlabeled L‐methionine, DL‐selenomethionine and d,l‐thiomalate were studied by nuclear magnetic resonance methods. The 13C NMR indicates that only Ag+ react with the both L‐methionine, DL‐selenomethionine at neutral and higher pH via CO2– and S or Se atom forming a chelate. The Ag(CN)2– and AgCN do not bind to either of these two ligands at any pH. The Ag13CN, which is an insoluble polymer, can react with thiomalate to form chelate complexes at neutral pH. Various structures for the chelate formations are proposed.
Enhancing infrared response of adsorbed biomaterials using ellipsometry and textured surfaces
Authors: Thompson Daniel W. , Woollam John A.
Published: March 2012

Infrared spectra are of interest for numerous applications because of the chemical bond information present in the absorption characteristics. Obtaining meaningful infrared spectra from monolayers adsorbed to surfaces can be difficult because of the small amount of material being probed. For instance, it is often of interest to probe adsorbates on a surface after exposure to a protein solution. Use of textured (patterned) surfaces to increase the mass of material sensed is expected to enhance these spectra. Here the infrared ellipsometric enhancement is calculated for a layer of adsorbate on a number of proposed nanostructured surfaces to predict which is most advantageous for obtaining infrared spectra. The approach used here could also be applied to other adsorbates by optimizing the pattern dimensions for different sizes. It also works for visible spectroscopy as long as pattern dimensions are significantly smaller than the wavelength. The effect of using these structures (rods, wells, and trenches) is compared to the response of flat metal or dielectric surfaces over a range of incidence angles of the infrared beam. Predicted sensitivities are based on the calculated effect of adsorbate on intensities in an ellipsometric measurement. Trench structures appear to have significant advantages both in sensitivity and ability to distinguish adsorbed species orientation.
A new method for studying platelets, based upon the low‐angle light scattering technique. 2. Application of the method in experimental toxicology and clinical pathology
Authors: Mindukshev Igor V. , Ermolaeva Elena E. , Vivulanets Elena V. , Shabanova Elena Yu. , Petrishchev Nikolay N. , Goncharov Nikolay V. , Jenkins Richard O. , Krivchenko Alexander I.
Published: March 2012

A new method for studying platelets based on low‐angle light scattering has been applied to studies in experimental toxicology and clinical pathology, using animal and human platelets. Index EC50 for ADP within control groups was estimated to be in the range of 100–180 nmol l–1 (healthy men, rabbits, rats). The refractory state of platelets was obtained by use ADP or ATP concentrations that just caused platelet activation. The time constant and the half‐cycle of the refractory state of platelets were calculated. Kinetic parameters of platelet aggregation at interference of hemostasis (rabbit) and the influence of the age factors on the aggregation indices of platelets (rat) were studied. The method of low‐angle light scattering was used as a diagnostic tool in experimental low‐level intoxication by organophosphates and for interpretation of the pathogenesis of delayed effects. In human patients with ischemic heart disease or with prosthetic heart valves, significant changes in the functional state of platelets were observed. A model for cooperative binding of receptors with ligands on platelets from pregnant women with preeclampsia was developed.
Near Infrared Spectroscopy (NIRS) in the clinical setting – An adjunct to monitoring during diagnosis and treatment
Authors: Gagnon R. E. , Macnab A. J.
Published: March 2012

Since clinical near infrared spectrophotometers (NIRS) first became commercially available in the early 1990′s there have been more than two thousand related peer reviewed reports in the medical literature. These encompass a wide range of human and animal trials that have been directed at validating the principles, methods, and algorithms underlying the technology, as well as demonstrating its potential for specific clinical uses such as detecting concealed bleeding, onset of hypoxia, progress of ischemia, and tissue oxygenation status within human brain, muscles, organs, and tumours. In addition to its standard use as a monitor of patterns of change in the concentrations of oxygenated, and de‐oxygenated hemoglobin residing in blood, NIRS has also been used to monitor patterns of change in the redox status of the cellular respiration enzyme, cytochrome c oxidase (Cyt a,a3) which utilizes the oxygen diffused from the blood. Accompanied by a tracer bolus of near infrared absorbing dye, NIRS has also been used to measure the proportional blood flow and blood volume transiting organs. NIRS has been used in conjunction with PET, fMRI, BOLD‐fMRI, TCD, vascular flowmetry, MRS, NMR, plethysmography, PO2 histography, EEG, ECG, EMG, SSEP, MEP, MEG, and standard bedside monitoring devices. Herein we summarize the history, technique, algorithms, methods and advances of clinical NIRS.
Raman spectroscopic study of photosensitive damage to lysozyme structure sensitized by hypocrellin A
Authors: Zhou J. H. , Wu X. H. , Wei S. H. , Gu X. T. , Feng Y. Y. , Wang X. S. , Zhang B. W.
Published: March 2012

Laser Raman spectroscopy was used to detect the nature of the structural change in lysozyme sensitized by hypocrellin A (HA) at the molecular level. The results indicated that the orderly structure of lysozyme has been damaged by the active oxygen (1O2, O2−· and .OH, etc.) generated by HA, and cause the changes in H‐bonds system of the main chain and the side chain of lysozyme.
The Influence of Mn2+ on DNA structure in the presence of Na+ ions: A Raman spectroscopic study
Authors: Muntean Cristina M. , Misselwitz Rolf , Welfle Heinz
Published: March 2012

The influence of Mn2+ ions on the structure of natural calf thymus DNA was studied by Raman spectroscopy. Measurements were done at room temperature and pH 6.2±0.2, in the presence of the physiological concentration of 150 mM Na+ ions, and in the presence of Mn2+ concentrations that varied between 0 and 600 mM. No condensation of DNA was observed at any of the Mn2+ concentrations. At 5 mM Mn2+ and 150 mM Na+ no significant influence of Mn2+ ions on the DNA structure can be observed. Compared with our previous results obtained at 10 mM Na+ ions, binding of Mn2+ ions to charged phosphate groups and to DNA bases is inhibited in the presence of 150 mM Na+ ions. DNA backbone conformational changes were not observed in the whole concentration range of Mn2+ ions as judging from the Raman spectra. No evidence for DNA melting was identified. A high Mn2+ affinity for binding to guanine N7 and possibly, in a much lesser extent, to adenine have been found.
Synchrotron IR microspectroscopy for protein structure analysis: Potential and questions
Authors: Yu Peiqiang
Published: March 2012

Synchrotron radiation‐based Fourier transform infrared microspectroscopy (S‐FTIR) has been developed as a rapid, direct, non‐destructive, bioanalytical technique. This technique takes advantage of synchrotron light brightness and small effective source size and is capable of exploring the molecular chemical make‐up within microstructures of a biological tissue without destruction of inherent structures at ultra‐spatial resolutions within cellular dimension. To date there has been very little application of this advanced technique to the study of pure protein inherent structure at a cellular level in biological tissues. In this review, a novel approach was introduced to show the potential of the newly developed, advanced synchrotron‐based analytical technology, which can be used to localize relatively “pure“ protein in the plant tissues and relatively reveal protein inherent structure and protein molecular chemical make‐up within intact tissue at cellular and subcellular levels. Several complex protein IR spectra data analytical techniques (Gaussian and Lorentzian multi‐component peak modeling, univariate and multivariate analysis, principal component analysis (PCA), and hierarchical cluster analysis (CLA) are employed to relatively reveal features of protein inherent structure and distinguish protein inherent structure differences between varieties/species and treatments in plant tissues. By using a multi‐peak modeling procedure, RELATIVE estimates (but not EXACT determinations) for protein secondary structure analysis can be made for comparison purpose. The issues of pro‐ and anti‐multi‐peaking modeling/fitting procedure for relative estimation of protein structure were discussed. By using the PCA and CLA analyses, the plant molecular structure can be qualitatively separate one group from another, statistically, even though the spectral assignments are not known. The synchrotron‐based technology provides a new approach for protein structure research in biological tissues at ultraspatial resolutions.
A simple spectrophotometric method for the determination of trace level lead in biological samples in the presence of aqueous micellar solutions
Authors: Khan Humaira , Ahmed M. Jamaluddin , Bhanger M. Iqbal
Published: March 2012

A very simple, ultra‐sensitive and fairly selective new spectrophotometric method has been developed for the rapid determination of lead(II) at ultra‐trace level using 1,5‐diphenylthiocarbazone (dithizone) in presence of aqueous micellar solutions. The proposed method enabled the determination of lead down to µg l−1 in human blood and urine in aqueous media without resource of any “clean‐up” step. The most remarkable point of this method is that the presence of micellar system avoids the previous steps of solvent extraction and reduces the cost, toxicity while enhancing the sensitivity, selectivity and the molar absorptivity. The complex formation of lead in blood with dithizone was completed within a minute at room temperature and the absorbance remains stable for 24 h. The average molar absorption coefficient and Sandell′s sensitivity were found to be 3.99×105 l mol−1 cm−1 and 30 ng cm−2 of Pb, respectively. Linear calibration graphs were obtained for 0.06–60 mg l−1 of PbII; the stoichiometric composition of the chelate is 1:2 (Pb:dithizone). The interference from over 60 cations, anions and complexing agents has been studied at 1 mg l−1 of PbII. The method was successfully used in the determination of lead in several biological samples (human blood and urine and bovine liver), solution containing both lead(II) and lead(IV) and complex synthetic mixtures. The results of biological analyses by the spectrophotometric method were in excellent agreement with those obtained by AAS. The results of lead concentration in biological samples were varied with age, sex and place which have been discussed.
Simultaneous in‐situ NIRS of liver and bowel during septic shock
Authors: Gagnon R. E. , Hahum E. , Skarsgard E. , Macnab A. J.
Published: March 2012

We wished to use near infrared spectroscopy (NIRS) to evaluate changes in blood perfusion in the liver and small bowel. However, conventional clinical NIRS probes use adhesive light shielding appliqués that fail in direct contact with the wetness and softness of the liver and small bowel surfaces. We describe our development and testing of customized NIRS probe holders.

Methods: Studies were conducted in 11 juvenile (9–17 kg) anesthetized Yorkshire piglets, with intact liver and bowel exposed during experimental septic shock induced by infusion of Escherichia coli. Internally, the emitter and detector of one NIRO‐300 channel were sheathed, directed towards each other, and affixed to the opposite arms of a long‐jawed ratchet clamp applied directly to the liver. The emitter and detector of the NIRO‐300′s second channel were applied, facing each other, on opposite inner surfaces of a semicircular, semi‐rigid, reinforced rubber tube through which a loop of the small bowel was drawn. Externally, optodes from a NIRO‐500 were applied to the skin over the liver. NIRS data were collected at 1second intervals for 180 minutes. Results: A wide range of optical neutral density filters was required to attenuate the emissions because of the diversity of tissue density between subjects. There were no complications with the liver clamp, and the initial tendency for the bowel to slip from the NIRS holder was solved by securing it with surgical ribbon. Conclusion: Since the NIRO‐300 control algorithm did not halt monitoring; the NIRO‐300 data correlated with the NIRO‐500 data (r2=0.292 to 0.659) and both were correlated with the mean arterial blood pressure (range: r2=0.309 to 0.918, p< 0.05 for r2 > 0.105), our modifications were deemed successful.
Applications of NMR spectroscopy in understanding the gold biochemistry
Authors: Isab Anvarhusein A. , Ahmad Saeed
Published: March 2012

Gold‐based drugs have been successfully used for the treatment of rheumatoid arthritis. When administered, they undergo ligand exchange reactions in the body with biofluids, cells and proteins. NMR spectroscopy is a very useful technique for probing these ligand exchange reactions under physiological conditions. The strength of the binding ligands can be estimated by studying the chemical shift changes in 13C and 31P NMR. It is also a powerful method for investigating the kinetics and thermodynamics of the exchange reactions of gold drugs with biomolecules. The purpose of this review report is to highlight the importance of NMR spectroscopy in the study of gold biochemistry and to bridge the fairly large gap in the progress of this interesting area of bioinorganic chemistry.
Dynamic MR imaging as a predictor of prognosis in breast cancer
Authors: Szabó Botond K. , Kristoffersen-Wiberg Maria
Published: March 2012

Contrast‐enhanced MR imaging (CE‐MRI) has become a widely accepted complementary method for diagnosing breast cancer. It has been suggested for evaluating patients with breast implants, patients at risk of tumour multifocality or recurrence, search for occult primary cancer in presence of axillary metastasis and monitoring the effect of preoperative chemotherapy. The clinical usefulness of MR imaging in patients with increased genetic risk of breast cancer is still under investigation. There is scientific evidence to support the hypothesis that CE‐MRI may carry the prognostic significance of angiogenesis, and one of the future indications of this method can be the prognostic evaluation of breast cancer patients by the functional mapping of the angiogenic activity of tumours. On the basis of the promising results of recent reports, further large‐scale studies are needed to evaluate the impact of MR parameters on long term overall survival of patients with breast cancer.
Mn2+–DNA interactions in aqueous systems: A Raman spectroscopic study
Authors: Muntean Cristina M. , Misselwitz Rolf , Dostál Lubomir , Welfle Heinz
Published: March 2012

Interaction of natural calf thymus DNA with Mn2+ ions was studied by means of Raman spectroscopy. Spectra of DNA in 10 mM Na‐cacodylate buffer, pH 6.2, 10 mM NaCl and in buffer containing Mn2+ ions were measured at room temperature. Mn2+ concentrations varied between 0 and 0.6 M. DNA backbone conformational changes and DNA denaturation were not observed in the concentration range 0 and 0.5 M, however, DNA condensation was observed at a critical concentration of 100 mM Mn2+ that prevented the measurement of Raman spectra. Binding of Mn2+ to the charged phosphate groups of DNA is indicated in the spectra. A high affinity of Mn2+ for guanine N7 was obvious, and binding to adenine was barely suggested.
Determination of the enantiomeric composition of chiral delta‐2‐thiazolines‐1,3 by 1H and 19F NMR spectroscopy using chiral solvating agents
Authors: Merelli Bérangère , Menguy Laurence , Soubeyrand-Lenoir Estelle , Cherton Jean-Claude
Published: March 2012

Studies of the perturbing effect of chiral solvating agents (CSAs) namely the fluoroalcohols 5a and 5b upon the NMR spectra of chiral Δ2‐thiazolines 1 presenting interesting insecticidal properties demonstrated the ability of these CSAs to afford diastereomeric solvates from these substrates providing their enantiomeric discrimination. Thus, for five of the six tested Δ2‐thiazolines 1A and 1B there is at least one possibility to proceed to their enantiomeric discrimination either by 1H or 19F NMR using mostly 5b as CSA.
The effective correlation time τ in jaw cysts determined from 400 MHz NMR T1 and T2 measurements
Authors: Budak Hatice , Köylü M. Zafer , Yilmaz U. Nezih
Published: March 2012

Macromolecular crowding is a general phenomenon of biological systems, and the evaluation of a correlation time for a specific molecule is difficult when the molecular crowding exists. The determination of an effective correlation time may therefore give useful insights into molecular dynamics of such systems. In this work, the relaxation rates in the mixture of D2O (80%) and cystic fluid (20%) were measured with a NMR operating at 400 MHz for three types of cysts (non‐infected radicular, infected radicular and hemorrhagic). The effective correlation times (τ values) were then determined by using a formula derived from the observed relaxation rates. The τ value of the infected cyst was found to be longer than those of the others for the studied cases. The present data suggest that an effective correlation time for fluids with macromolecular crowding can be determined from NMR relaxation measurements.
Spectroscopy of biological nanocrystals
Authors: Ortac Inanc , Severcan Feride
Published: March 2012

Nanocrystals have gained much interest in recent years, due to their unusual properties allowing interesting applications in physical and biological science. In this literature review, biological nanocrystals are discussed from the spectroscopic point of view. Firstly, the theory behind the outstanding abilities of the nanocrystals is described. Secondly, the spectroscopic properties of biological nanocrystals are mentioned. Lastly, the use of nanocrystals with various spectroscopic applications is reviewed such as biosensor applications with UV–visible and surface plasmon resonance and Raman spectroscopy of biological materials. Finally, a short discussion of infrared nanocrystals and their abilities are included in the review.
Binding studies of paeonolum with bovine serum albumin using spectroscopic methods
Authors: Chen Chang-yun , Gu Xiao-tian , Zhou Jia-hong
Published: March 2012

Fluorescence and UV spectroscopic techniques were used to investigate the interaction of Paeonolum, one of the major bioactive components isolated from the bark of peony plant, with bovine serum albumin (BSA). Results obtained reveal that a binding interaction occurs between paeonolum and BSA under physiological conditions, and the interaction can quench the fluorescence of BSA originating from the complex formation between paeonolum and BSA. In addition, according to the thermodynamics parameters of this interaction process, it appears that this binding interaction is mainly hydrophobic in nature.
On the prenylation of some indolic and imidazolic bases by oxirane auxiliaries under thermal and microwave conditions
Authors: Jankowski Christopher K. , Dako Etienne , Laouz Antoun Bou , Delaforge Marcel , Paré Jocelyn R. J. , Belanger Jacqueline M. R.
Published: March 2012

The analogue of isoprene, 2‐methyl‐2‐vinyloxirane, a versatile isoprene auxiliary, was reacted with some indolic and imidazolic bases, to add one or more isoprene unit(s), to these compounds. This prenylation was realised by using thermal and microwave assisted pathways, via the nucleophilic opening of the epoxide ring. The biological importance of the prenylated derivatives resides in their potential application as drugs. The aminoacids and small protein biomarkers are obtained from simple epoxide opening reactions. All new compounds were characterised by high resolution NMR, mass spectroscopy, GC‐MS and LC‐MS as well.
Investigation of diabetes‐induced effect on apex of rat heart myocardium by using cluster analysis and neural network approach: An FTIR study
Authors: Toyran Neslihan , Severcan Feride , Severcan Mete , Turan Belma
Published: March 2012

Diabetes mellitus (DM) is a progressive chronic disorder, which affects people belonging to all age groups of the population. This disease is accompanied by a greatly increased risk of cardiovascular death. In the present study, the effects of streptozotocin (STZ)‐induced type 1 diabetes on apex myocardium of the rat heart have been investigated using Fourier Transform Infrared (FTIR) spectra. The cluster analysis has been applied to FTIR spectra to differentiate the diabetic samples from the normal controls. In addition, the protein secondary structures of diabetic and normal tissues were predicted by neural networks based on the amide I band of the FTIR spectra. The findings mainly suggest that 5 weeks of diabetes alters the lipid and protein profile of normal rat heart apex myocardium, which might have an important role in understanding the molecular mechanism of diabetes‐related heart diseases.
FT‐IR and Raman vibrational microspectroscopies used for spectral biodiagnosis of human tissues
Authors: Lin Shan-Yang , Li Mei-Jane , Cheng Wen-Ting
Published: March 2012

Fourier transform infrared (FT‐IR) and Raman vibrational microspectroscopies used for biomedical diagnosis of human tissues are reviewed from basic principle to biological applications. The advantages and disadvantages of both vibrational microspectroscopies are compared to highlight their efficiency and adaptability for noninvasively investigating the chemical compositions of ultrastructual human tissues at different disease states. Biochemical fingerprints applied to the biological samples by using FT‐IR and Raman microspectroscopies are illustrated. The spectral biodiagnoses of several diseased human tissues such as ophthalmic disorders (risk factors‐induced cataractous lens capsules and lens, lens and corneal calcifications, opacification and contamination of intraocular lens, vitreous asteroid bodies), alcohol‐disordered human gastric mucosa, skin disorders (cancer and calcification), brain tumors (pituitary adenomas and astrocytomas), genetic hair roots disorder (glucose‐6‐phosphate dehydrogenase deficiency, phenylketonuria and congenital hypothyroidism), benign prostatic hyperplasia, and interstitial cystitis investigated by both vibrational microspectroscopies in our laboratory are introduced.
The structural stability of protein antigens adsorbed by aluminium hydroxide in comparison to the antigens in solutions
Authors: Zheng Yiwu , Lai Xuxin , Ipsen Henrik , Larsen Jørgen Nedergaard , Løwenstein Henning , Søndergaard Ib , Jacobsen Susanne
Published: March 2012

It is believed that antigens should be adsorbed onto adjuvants in vaccines. The adsorption‐modified structure of antigens is important to understand the mechanism of adjuvants and vaccine immunogenicity. The structural stability of antigens is of major importance. The changes in structure can be induced by degradation and/or increase of storage temperature. In this study the structural stability of two model antigens, bovine serum albumin (BSA) and β‐lactoglobulin (BLG) were compared when they were adsorbed onto aluminium hydroxide and when they were in solutions using Fourier transform infrared – attenuated total reflection (FTIR‐ATR) spectroscopy. The structural stability of these two proteins was studied at different temperature and during storages. The present results showed that the structure of antigens can be stabilized by adsorption onto aluminium hydroxide. Non‐adsorbed protein antigens present in vaccines may facilitate the degradation of the vaccine.
The effect of diabetes mellitus on rat skeletal extensor digitorum longus muscle tissue: An FTIR study
Authors: Bozkurt Ozlem , Bilgin Mehmet Dincer , Severcan Feride
Published: March 2012

Diabetes mellitus (DM) is a chronic disorder of carbohydrate, fat and protein metabolism, which is characterized by a defective insulin secretory response. Skeletal muscle takes role in determination of carbohydrate and lipid metabolism, therefore; it is one of the target tissues of diabetes. Herein this study, application of Fourier Transform Infrared (FTIR) spectroscopy in diabetic skeletal Extensor Digitorum Longus (EDL) muscle tissues will be presented which highlight the promise of this technique in medical research. Type I DM was induced in rats by injection of streptozotocin (STZ) which is one of the most popular experimental models. In diabetes, a significant increase was observed in lipid order together with an increase in hydration of phospholipid molecules in membrane structure. There was a decrease in lipid and nucleic acid content in diabetic EDL muscles. A dramatic increase in the bandwidth of amide II band (1540 cm−1) and shifting of the position of this band to lower frequency values in diabetes was observed indicating structural changes occurring in proteins of diabetic EDL muscles.
Formation of unilamellar dipalmitoylphosphatidylcholine vesicles promoted by Ca2+ ions: A small‐angle neutron scattering study
Authors: Uhríková Daniela , Teixeira José , Lengyel Adrián , Almásy László , Balgavý Pavol
Published: March 2012

Dipalmitoylphosphatidylcholine (DPPC) was hydrated in 0.2–60 mM solution of CaCl2 in heavy water and thoroughly homogenized by freezing‐thawing process. Small‐angle neutron scattering (SANS) shows formation of unilamellar vesicles in the range 1–60 mM of CaCl2. From the Kratky–Porod plot ln [I(Q)Q2] vs. Q2 of SANS intensity I(Q) in the range of scattering vectors Q corresponding to the interval 0.001 Å−2≤Q2≤0.006 Å−2, the vesicle bilayer radius of gyration Rg and the bilayer thickness parameter dg were obtained. The structure of the bilayer displays different behavior for the gel phase and the liquid‐crystalline phase: In the gel phase (at 20°C), the values of dg indicate nonlinear changes in the lipid bilayer thickness, with a maximum at ~5 mM CaCl2. In the liquid‐crystalline phase (at 60°C), the parameter of the lipid bilayer thickness dg=43.2±0.3 Å is constant within the concentration range 1≤cCa≤40 mM. Vesicles prepared at 60 mM CaCl2 show within experimental error, the same values of dg as pure DPPC unilamellar vesicles prepared by extrusion using polycarbonate filter with pores of diameter 500 Å.
Spectroscopy of gadolinium ion and disadvantages of gadolinium impurity in tissue compensators and collimators, used in radiation treatment planning
Authors: Maqbool M. , Ahmad Iftikhar
Published: March 2012

Intense ultraviolet emission from gadolinium doped amorphous aluminum nitride thin films deposited on Si (111) substrate is studied with cathodoluminescence and photoluminescence. The purpose of the study is to find the merits or demerits of gadolinium ions if added intentionally or present as unintentionally added impurity in tissue compensators or collimators in radiation treatment planning. These films are deposited by reactive sputtering at liquid nitrogen temperature, using 100–200 W RF power, 5–8 mTorr nitrogen, and a metal target of aluminum and gadolinium. Thermal annealing was performed at a temperature of 900౨C. A sharp ultraviolet peak is observed at 314 nm corresponding to 6P7/2→8S7/2 transition. The ultraviolet emission is intense enough to harm human tissues if it is used as tissue compensator. Intense ultraviolet emission is observable even if the concentration of gadolinium is less than 0.5%. Thermal annealing further enhances the intensity of ultraviolet emission, indicating that longer use of such tissue compensators or collimators containing gadolinium ions will provide more harm and damage to human body. Radiation Therapists, Oncologist and industries making tissue compensators and collimators are strongly suggested to test any compensator or collimator for gadolinium impurities.
Rapid assay of picogram level of sudan I in hot chilli sauce by flow injection chemiluminescence
Authors: Gao Xiaofei , Liu Houyong , Song Zhenghua , He Xili , Dong Faxin
Published: March 2012

A novel chemiluminescence method for the assay of sudan I was designed using flow injection with chemiluminescence detection. The proposed method was based on the increment effect of sudan I on the chemiluminescence intensity in the luminol–KIO4 system. The increment of chemiluminescence intensity was correlated with the sudan I concentration in the range from 0.1 to 10 pg ml−1, and the determination could be performed in 0.5 min in flow rate of 2 ml min−1, including sampling and washing, giving a throughput of 120 h−1 with a relative standard deviation of less than 5.0%. The method had been successfully applied to the assay of sudan I in Pixian douban, Golden mark guilin chilli sauce and Golden mark satay sauce, and the recovery was 90.0–103.8%.
NMR spectroscopic study of inclusion complexes of cetirizine dihydrochloride and β‐cyclodextrin in solution
Authors: Ali Syed Mashhood , Upadhyay Santosh Kumar , Maheshwari Arti
Published: March 2012

Cetirizine dihydrochloride (CTZ), an antihistamine, forms two 1:1 inclusion complexes with β‐cyclodextrin (β‐CD) in aqueous solution as confirmed by detailed 1H NMR, COSY and ROESY spectroscopic studies. The stoichiometry and overall binding constant of the complexes were determined by the treatment of 1H NMR chemical shift change (Δδ) data. Most of the CTZ protons exhibited splitting in the presence of β‐CD.
Diversity of Species and Behavior of Hymenopteran Parasitoids of Ants: A Review
Authors: Lachaud Jean-Paul , Pérez-Lachaud Gabriela
Published: March 2012

Reports of hymenopterans associated with ants involve more than 500 species, but only a fraction unambiguously pertain to actual parasitoids. In this paper, we attempt to provide an overview of both the diversity of these parasitoid wasps and the diversity of the types of interactions they have formed with their ant hosts. The reliable list of parasitoid wasps using ants as primary hosts includes at least 138 species, reported between 1852 and 2011, distributed among 9 families from 3 superfamilies. These parasitoids exhibit a wide array of biologies and developmental strategies: ecto- or endoparasitism, solitary or gregarious, and idio- or koinobiosis. All castes of ants and all developmental stages, excepting eggs, are possible targets. Some species parasitize adult worker ants while foraging or performing other activities outside the nest; however, in most cases, parasitoids attack ant larvae either inside or outside their nests. Based on their abundance and success in attacking ants, some parasitoid wasps like diapriids and eucharitids seem excellent potential models to explore how parasitoids impact ant colony demography, population biology, and ant community structure. Despite a significant increase in our knowledge of hymenopteran parasitoids of ants, most of them remain to be discovered.