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Introduction. Hyperbaric oxygen therapy is a treatment option for an increasing number of conditions. The aim of this study was to assess its therapeutic effects in femoral condylar necrosis as well as in normal tissue using hyperspectral imaging. Material and method. A 47-year-old female patient diagnosed with avascular necrosis of the medial femoral condyle was included in this study. The patient received hyperbaric oxygen therapy for two consecutive days (the first day: three stages of 30 min each, separated by two breaks of 5 min at pO2 = 2 ATA; the second day: three stages of 30 min each, separated by two breaks of 5 min at pO2 = 2.4 ATA). The effects of hyperbaric oxygen therapy on the affected area (patient’s knee) and normal (patient’s hand) tissues oxygenation were assessed before and after each treatment session using hyperspectral imaging. Results and discussions. The results showed that hyperspectral imaging is quite good for monitoring the hyperbaric oxygen therapy efficacy in affected areas, even with deep tissue problems. Conclusions. In conclusion, the hyperspectral imaging-based approach for monitoring hyperbaric oxygen therapy could support physicians in extracting prognostic information and making the right treatment decisions. Keywords: bone necrosis, image analysis, maps, oxyhemoglobin, deoxyhemoglobin, oxygen saturation

Background and Objectives: The compression of human skin is one of the mechanisms of mechanical biotissue optical clearing. In this study we investigated the effects of compression of in vitro cow muscle tissue samples on diffuse reflectance spectra of tissue and changes of its physiological properties. The purpose of research was to identify the correlation between diffuse reflectance of muscle tissue and its compression. Material and Methods: Samples of muscle tissue used in the experiments with a size of 70–50 mm and a thickness of 25 mm were cut from one volume of the loin hart of a cow. After applying pressure to the sample for a time of about 20 minutes, reflectance spectra of the samples were recorded with a time step of 5 seconds. In the experiments, sensors of different sizes were varied with different values of the applied external compression. Results: The dynamics of myoglobin and hemoglobin content in muscle tissue ex vivo in the compression process was determined. In the case of muscle tissue ex vivo, the blood content in it decreases when compression is applied. A similar effect was observed for skin tissue in vivo, but there are also significant differences: if for skin tissue capillary blood, and hemoglobin, when a pressure of about 105 Pa is applied, is completely removed from biological tissue, then myoglobin from muscle tissue samples is not completely removed, the oxygenated form of myoglobin turns into deoxygenated and deoxygenation of myoglobin occurs within a few minutes after the application of compression. Conclusion: In perspective compression of muscle tissue ex vivo can become the basis for a method for controlling the content of hemoglobin and myoglobin derivatives and, as a result, for controlling the color of biological tissue.

The electronic structure of the heme oxy-iron center in oxyhemoglobin and oxymyoglobin has been the subject of debate for decades. Various experimental and computational methods have been used to study this system, leading to conflicting conclusions. This study uses X-ray spectroscopy to directly probe the iron center in the highly delocalized oxyhemoglobin and its model compound to define the electronic structure and understand the differences between the protein and the model. This study settles a longstanding debate in bioinorganic chemistry and provides insight into heme iron–oxygen binding, the key first step in many biocatalytic processes.Hemoglobin and myoglobin are oxygen-binding proteins with S = 0 heme FeO28 active sites. The electronic structure of these sites has been the subject of much debate. This study utilizes Fe K-edge X-ray absorption spectroscopy (XAS) and 1s2p resonant inelastic X-ray scattering (RIXS) to study oxyhemoglobin and a related heme FeO28 model compound, [(pfp)Fe(1-MeIm)(O2)] (pfp = meso-tetra(α,α,α,α-o-pivalamido-phenyl)porphyrin, or TpivPP, 1-MeIm = 1-methylimidazole) (pfpO2), which was previously analyzed using L-edge XAS. The K-edge XAS and RIXS data of pfpO2 and oxyhemoglobin are compared with the data for low-spin FeII and FeIII [Fe(tpp)(Im)2]0/+ (tpp = tetra-phenyl porphyrin) compounds, which serve as heme references. The X-ray data show that pfpO2 is similar to FeII, while oxyhemoglobin is qualitatively similar to FeIII, but with significant quantitative differences. Density-functional theory (DFT) calculations show that the difference between pfpO2 and oxyhemoglobin is due to a distal histidine H bond to O2 and the less hydrophobic environment in the protein, which lead to more backbonding into the O2. A valence bond configuration interaction multiplet model is used to analyze the RIXS data and show that pfpO2 is dominantly FeII with 6–8% FeIII character, while oxyhemoglobin has a very mixed wave function that has 50–77% FeIII character and a partially polarized Fe–O2 π-bond.

Background: Many adult females experience periodic mental and physical symptoms associated with premenstrual syndrome (PMS). Diagnosis of PMS is generally based on self-reported symptoms over several menstrual cycles, but there are concerns about its accuracy and duration. It is well known that decreased cognitive function is one of the symptoms of PMS. Near-infrared spectroscopy (NIRS) is one of the methods for imaging brain activity, similar to magnetic resonance imaging (MRI), electroencephalography (EEG), and positron emission tomography (PET). NIRS has been used to assess cognitive function decline demonstrated by decline in brain activity. However, to the best of our knowledge, there have been no report characterizing brain activity pattern in females with PMS during the luteal and follicular phases separately. Objective: We aimed to characterize the cognitive function of females with PMS during the follicular and luteal phases using NIRS. Methods: The level of brain activity in the prefrontal cortex was detected with NIRS while PMS women were performing cognitive tasks. NIRS detected brain activity by measuring the oxy-hemoglobin and deoxy-hemoglobin levels. Participants were females between the ages of 20 and 25 with PMS (n = 11) and without PMS (n = 11). During the participants’ follicular and luteal phases, the participants were asked to perform the cognitive task; an N-back task (0-, 1-, and 2-back tasks), which is widely used for assessing cognitive function. We also calculated the oxyhemoglobin integral value during the N-back task using the NIRS signal; this value represented the total amount of change in cerebral oxyhemoglobin and the brain activation level. Results: The correct response rate on the 2-back task was significantly lower during both the follicular and luteal phases in females with PMS compared to that in females without PMS (P = 0.01; P = 0.02, during the follicular and luteal phases, respectively). During the luteal phase, brain activation was significantly lower in participants with PMS than in that in females without PMS (P = 0.04). In addition, during the luteal phase, the participants with PMS also had higher negative mood than those without PMS. Conclusion: The cognitive decline during the luteal phase in participants with PMS was detected by NIRS with significant differences from participants without PMS. The difference was observed only during the luteal phase, not in the follicular phase and were related to the increase in negative mood. These results may provide an objective method for diagnosing PMS based on brain activity. We believe that the use of instruments (e.g., NIRS, MRI, EEG … etc.) to detect cognitive function decline will lead to rapid and reliable diagnosis of PMS and premenstrual dysphoric disorder.

Background We have previously verified the beneficial effects of exosomes from endothelial progenitor cells (EPC-EXs) in ischemic stroke. However, the effects of EPC-EXs in hemorrhagic stroke have not been investigated. Additionally, miR-137 is reported to regulate ferroptosis and to be involved in the neuroprotection against ischemic stroke. Hence, the present work explored the effects of miR-137-overexpressing EPC-EXs on apoptosis, mitochondrial dysfunction, and ferroptosis in oxyhemoglobin (oxyHb)-injured SH-SY5Y cells. Methods The lentiviral miR-137 was transfected into EPCs and then the EPC-EXs were collected. RT-PCR was used to detect the miR-137 level in EPCs, EXs, and neurons. The uptake mechanisms of EPC-EXs in SH-SY5Y cells were explored by the co-incubation of Dynasore, Pitstop 2, Ly294002, and Genistein. After the transfection of different types of EPC-EXs, flow cytometry and expression of cytochrome c and cleaved caspase-3 were used to detect the apoptosis of oxyHb-injured neurons. Neuronal mitochondrial function was assessed by reactive oxygen species (ROS) level, mitochondrial membrane potential (MMP) depolarization, and cellular ATP content. Cell ferroptosis was measured by lipid peroxidation, iron overload, degradation of glutathione, and glutathione peroxidase 4. Additionally, recombinational PGE2 was used to detect if activation of COX2/PGE2 pathway could reverse the protection of miR-137 overexpression. Results The present work showed (1) EPC-EXs could be taken in by SH-SY5Y cells via caveolin-/clathrin-mediated pathways and macropinocytosis; (2) miR-137 was decreased in neurons after oxyHb treatment, and EXsmiR-137 could restore the miR-137 levels; (3) EXsmiR-137 worked better than EXs in reducing the number of apoptotic neurons and pro-apoptotic protein expression after oxyHb treatment; (4) EXsmiR-137 are more effective in improving the cellular MMP, ROS, and ATP level; (5) EXsmiR-137, but not EXs, protected oxyHb-treated SH-SY5Y cells against lipid peroxidation, iron overload, degradation of glutathione, and glutathione peroxidase 4; and (6) EXsmiR-137 suppressed the expression of the COX2/PGE2 pathway, and activation of the pathway could partially reverse the neuroprotective effects of EXsmiR-137. Conclusion miR-137 overexpression boosts the neuroprotective effects of EPC-EXs against apoptosis and mitochondrial dysfunction in oxyHb-treated SH-SY5Y cells. Furthermore, EXsmiR-137 rather than EXs can restore the decrease in miR-137 levels and inhibit ferroptosis, and the protection mechanism might involve the miR-137-COX2/PGE2 signaling pathway.

Individuals with Chronic Obstructive Pulmonary Disease (COPD) experience sleep disturbances due to the impact of respiratory symptoms on sleep quality. We explored whether sleep disturbances in COPD are linked to heterogeneity of airway constriction.The impact of breathing problems on sleep quality was measured in consecutive COPD outpatients with the COPD and Asthma Sleep Impact Scale (CASIS) questionnaire. Impulse oscillometry technique (IOS) was employed to assess heterogeneity of airway constriction. Subjects with a previous or concomitant diagnosis of asthma or obstructive sleep apnea (OSA) were excluded.Fifty COPD subjects (M/F 40/10; age: 71 +/- 8 yrs, Body Mass Index (BMI): 26.2 +/- 4.7 kg/m(2), Forced Expiratory Volume in the first second (FEV1): 65 +/- 25% predicted; mean +/- SD) were enrolled. The mean CASIS score was 36 +/- 3.3, and the R5-R20 value was 0.2 +/- 0.15 kPa s L-1. The CASIS score was significantly higher in subjects with increased R5-R20 (>0.07 kPa s L-1) (39 +/- 24; p = 0.02) compared to normal R5-R20 (21 +/- 17). When subjects were categorized on the basis of lung function in severely versus non severely obstructed (FEV1 50% predicted) or air trappers versus non air trappers (Residual Volume, RV >= or

Background Globally, snake envenomation is a well-known cause of death and morbidity. In many cases of snakebite, myonecrosis, dermonecrosis, hemorrhage and neurotoxicity are present. Some of these symptoms may be provoked by the envenomation itself, but others are secondary effects of the produced oxidative stress that enhances the damage produced by the venom toxins. The only oxidative stress effect known in blood is the change in oxidation number of Fe (from ferrous to ferric) in hemoglobin, generating methemoglobin but not in other macromolecules. Currently, the effects of the overproduction of methemoglobin derived from snake venom are not extensively recorded. Therefore, the present study aims to describe the oxidative stress induced by Crotalus molossus nigrescens venom using erythrocytes. Methods Human erythrocytes were washed and incubated with different Crotalus molossus nigrescens venom concentrations (0–640 μg/mL). After 24 h, the hemolytic activity was measured followed by attenuated total reflectance-Fourier transform infrared spectroscopy, non-denaturing PAGE, conjugated diene and thiobarbituric acid reactive substances determination. Results Low concentrations of venom (40 μg/mL). This substance is not degraded by proteases present in the venom. By infrared spectroscopy, starting in 80 μg/mL, we observed changes in bands that are associated with protein damage (1660 and 1540 cm−1) and lipid peroxidation (2960, 2920 and 1740 cm−1). Lipid peroxidation was confirmed by conjugated diene and thiobarbituric acid reactive substance determination, in which differences were observed between the control and erythrocytes treated with venom. Conclusions Crotalus molossus nigrescens venom provokes hemolysis and oxidative stress, which induces methemoglobin formation, loss of protein structure and lipid peroxidation.

Results of quantum-chemical X(alpha)-discrete variation method (X(alpha)-DVM) calculations of interaction parameters between iron (II) and oxygen molecule in active sites of alpha- and beta-subunits of oxyhemoglobin are presented within three models: without extra electron and in spin-unrestricted mode (model I); without extra electron and in spin-restricted mode (model II); with extra electrons in spin-unrestricted mode (model III). The electronic structure and (57)Fe quadrupole splitting Delta E(Q) for the active site of alpha- and beta-subunits (within model I) and only of the alpha-subunit (within models II and III) of oxyhemoglobin are calculated. The differences in Delta E(Q) values for these three models are discussed.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:27:28Z No. of bitstreams: 0 Made available in DSpace on 2014-05-27T11:27:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-01-01 The urea effect on the giant extracellular hemoglobin of Glossoscolex paulistus (HbGp) stability was studied by analytical ultracentrifugation (AUC) and small angle X-ray scattering (SAXS). AUC data show that the sedimentation coefficient distributions curves c (S), at 1.0mol/L of urea, display a single peak at 57 S, associated to the undissociated protein. The increase in urea concentration, up to 4.0mol/L, induces the appearance of smaller species, due to oligomeric dissociation. The sedimentation coefficients and molecular masses are 9.2S and 204kDa for the dodecamer (abcd)3, 5.5S and 69kDa for the tetramer (abcd), 4.1S and 52kDa for the trimer (abc) and 2.0 S and 17kDa for the monomer d, respectively. SAXS data show initially a decrease in the I(0) values due to the oligomeric dissociation, and then, above 4.0mol/L of denaturant, for oxy-HbGp, and above 6.0mol/L for cyanomet-HbGp, an increase in the maximum dimension and gyration radius is observed, due to the unfolding process. According to AUC and SAXS data the HbGp unfolding is described by two phases: the first one, at low urea concentration, below 4.0mol/L, characterizes the oligomeric dissociation, while the second one, at higher urea concentration, is associated to the unfolding of dissociated species. Our results are complementary to a recent report based on spectroscopic observations. © 2012 Elsevier B.V. Instituto de Química de São Carlos Universidade de São Paulo, SP Universidade Estadual Paulista Julio de Mesquita Filho Registro, São Paulo, SP Universidade Estadual Paulista Julio de Mesquita Filho Registro, São Paulo, SP

In order to obtain information on the structural aspects of hemoglobin (Hb), Fourier transform Raman (FT-R) measurements on various ferrous, ferric derivatives and nickel reconstituted Hb (NiHb) has been made. FT-R spectra for these derivatives were obtained by laser excitation in the near infrared region (NIR) (1064 nm) whereby the wave-number region (600-1700 cm-1) related to both porphyrin ring modes and some globin modes were monitored. Comparison of various modes was made based on previous resonance Raman (RR) results. The wave-number shifts with respect to changes in oxidation state and spin state are very similar to those observed by RR. Additional bands at 1654, 1459, and 1003 cm-1 for deoxyHb and at 1656, 1454, and 1004 cm-1 for oxy Hb can be correlated to globin modes. The shift in the position of these bands for the binding of oxygen can be related to changes in conformation during the transformation. The presence of two distinct sites in NiHb could be monitored by the use of FT-R technique. ? 1999 Elsevier Science B.V. All rights reserved.

Cerebral hemodynamics and oxygenation in 18 perinatally asphyxiated neonates were compared with 13 healthy controls using near-infrared spectroscopy (NIRS) at the Dept of Pediatrics, University Hospital of Leiden, The Netherlands.

Red blood cell samples from several patients with erythremia have been studied by Mossbauer spectroscopy. Quadrupole splitting and isomer shift for oxyhemoglobin from erythremic red blood cells and those of oxyhemoglobin from normal ones differ slightly, while these hyperfine parameters for deoxyhemoglobins are the same. An additional component in Mossbauer spectra of red blood cell samples was observed in some cases of erythremia. It is proposed that this component is related to ferritin-like iron and its content ranged from 13-15% to 5-7%. Mossbauer spectroscopy; Erythremia; Hemoglobin; Fe2+ electronic structure; Ferritin; (Normal adult red blood cell, Erythremic red blood cell)

Affinity precipitation was compared to affinity chromatography and batch adsorption as the final purification step in a protocol for the isolation of haemoglobin from human blood. Haptoglobin was the affinity ligand. The first steps on the process were realized by traditional methods (lyses of red blood cells followed by ammonium sulphate precipitation). For affinity chromatography (and batch adsorption) the ligand was linked to Sepharose, for affinity precipitation to a thermoresponsive polymer, namely poly(N-isopropylacrylamide). Five haptoglobin-poly(N-isopropylacrylamide) bioconjugates (affinity macroligands) were constructed with different polymer: haptoglobin-coupling ratios. Conjugation of haptoglobin to the soluble poly(N-isopropylacrylamide) apparently does not change the interaction thermodynamics with haemoglobin, as the haemoglobin binding constants calculated by a Scatchard analysis for the affinity macroligand were of the same order of magnitude as those described in the literature for the haemoglobin-haptoglobin complex in solution. Two elution protocols were used for haemoglobin release from the various affinity materials, one at pH 2, the other with 5 M urea at pH 11. Both affinity chromatography and affinity precipitation yielded a pure haemoglobin of high quality. Compared to the affinity chromatography, affinity precipitation showed a significantly higher ligand efficiency (ratio of the experimental capacity to the theoretical one). The method thus makes better use of the expensive affinity ligands. As affinity precipitation only requires small temperature changes to bring about precipitation/redissolution of the affinity complexes and a centrifugation step for recovery of the precipitate, the method in addition has advantages in term of scalability and simplicity. (C) 2008 Elsevier B.V. All rights reserved.