Near-infrared photobiomodulation of blood reversibly inhibits platelet reactivity and reduces hemolysis.

Photobiomodulation (PBM) in the red/near-infrared (R/NIR) spectral range has become widely recognized due to its anti-inflammatory and cytoprotective potential. We aimed to assess the effects of blood PBM on platelets function and hemolysis in an in vitro setting. Porcine blood samples were separated into four aliquots for this study, one of which served as a control, while the other three were subjected to three different NIR PBM dosages. The platelet count and functions and the plasma free haemoglobin and osmotic fragility of red blood cells were measured during the experiment. The control group had a considerable drop in platelet number, but the NIR exposed samples had more minimal and strictly dose-dependent alterations. These modifications were consistent with ADP and collagen-induced platelet aggregation. Furthermore, red blood cells that had received PBM were more resistant to osmotic stress and less prone to hemolysis, as seen by a slightly lower quantity of plasma free hemoglobin. Here we showed under well-controlled in vitro conditions that PBM reversibly inhibits platelet activation in a dose-dependent manner and reduces hemolysis.

Publisher Correction: Low-level light therapy reduces platelet destruction during extracorporeal circulation.

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Low-level light therapy reduces platelet destruction during extracorporeal circulation.

Extracorporeal circulation causes many deleterious effects on blood cells. Low-level light therapy (LLLT) in the red/near-infrared spectral range is known for its cytoprotective properties but its use during cardiopulmonary bypass (CPB) has not yet been studied. We aimed to assess whether LLLT protects platelets during CPB. 24 pigs were connected to 1-hour-CPB and observed for the next 23 hours. In 12 animals, blood circulating through the oxygenator was treated with LLLT. Platelet count and function were monitored throughout the experiment. The decrease in platelet count was greater in the control group, especially during CPB and after 24 hours. In LLLT group CD62P expression remained quite stable up to the 12th hour of the experiment, whereas in the control group it continuously decreased till the end of observation. Platelets in the control group were more prone to aggregation in the postoperative period than at the beginning of the experiment, whereas platelets in the LLLT group aggregated similarly or less intense. Limitation of platelet loss, pattern of aggregation and CD62P expression suggest that LLLT may stabilize platelet function during CPB and diminish the negative effects associated with the interaction of cells with an artificial surface.

Sheep model of haemodialysis treatment.

More than two million patients received haemodialysis (HD) in 2013. Many methods for improving dialysis therapy outcomes have been tested. Nevertheless, patients continue to experience high morbidity and mortality rates. We aimed to develop an animal model of HD treatment to study methods that would prevent the adverse effects of renal replacement therapy. The study was conducted using six male Merino sheep. The animals underwent a two-step bilateral nephrectomy, and a permanent dual-lumen catheter was inserted into the jugular vein. In each animal, 10 short, daily HD treatments were conducted. The dialysis prescription was adjusted individually to each animal. Measures of dialysis adequacy (spKt/V and urea reduction ratio [URR]) were calculated for each HD treatment. All animals remained in a good clinical state during the experiment. However, a sustained decrease in red blood cell count was detected. The average URR was 0.65 ± 0.01, whereas the calculated spKt/V was approximately 1.16 ± 0.03. Neither hyperphosphataemia nor a significant decline in serum albumin concentrations were detected during the study. A sustained increase in serum potassium concentrations was detected on consecutive days of the experiment. All sheep survived the treatment and were euthanized at the end of the experiment. In conclusion, we developed a reproducible sheep model of HD treatment. The gentle nature and specific anatomical features of sheep provided easy blood access and allowed us to perform HD without pharmacological intervention. However, some differences in sheep physiology relative to human physiology must be considered when interpreting the results of the study.

Serial Lung Ultrasonography to Monitor Patient With Diffuse Alveolar Hemorhage.

Diffuse alveolar haemorrhage (DAH) leads to acute respiratory failure. This is why it requires rapid diagnosis and implementation of appropriate treatment. The standard diagnosis of a patient with DAH includes laboratory tests, diagnostic imagining (X-ray of the chest, high-resolution computed tomography), and bronchoscopy with bronchoalveolar lavage. We present a description of 2 patients diagnosed with systemic connective tissue disease and DAH, monitored with the help of lung ultrasound. To our knowledge, this is the first description of the use of lung ultrasound in DAH in adult patients.

Near infrared light induces post-translational modifications of human red blood cell proteins.

There is a growing body of evidence that near infrared (NIR) light exerts beneficial effects on cells. Its usefulness in the treatment of cancer, acute brain injuries, strokes and neurodegenerative disorders has been proposed. The mechanism of the NIR action is probably of photochemical nature, however it is not fully understood. Here, using a relatively simple biological model, human red blood cells (RBCs), and a polychromatic non-polarized light source, we investigate the impact of NIR radiation on the oxygen carrier, hemoglobin (Hb), and anion exchanger (AE1, Band 3). The exposure of intact RBCs to NIR light causes quaternary transitions in Hb, dehydration of proteins and decreases the amount of physiologically inactive methemoglobin, as detected by Raman spectroscopy. These effects are accompanied by a lowering of the intracellular pH (pHi) and changes in the cell membrane topography, as documented by atomic force microscopy (AFM). All those changes are in line with our previous studies where alterations of the membrane fluidity and membrane potential were attributed to NIR action on RBCs. The rate of the above listed changes depends strictly on the dose of NIR light that the cells receive, nonetheless it should not be considered as a thermal effect.

Application of FTIR-ATR Spectroscopy to Determine the Extent of Lipid Peroxidation in Plasma during Haemodialysis.

During a haemodialysis (HD), because of the contact of blood with the surface of the dialyser, the immune system becomes activated and reactive oxygen species (ROS) are released into plasma. Particularly exposed to the ROS are lipids and proteins contained in plasma, which undergo peroxidation. The main breakdown product of oxidized lipids is the malondialdehyde (MDA). A common method for measuring the concentration of MDA is a thiobarbituric acid reactive substances (TBARS) method. Despite the formation of MDA in plasma during HD, its concentration decreases because it is removed from the blood in the dialyser. Therefore, this research proposes the Fourier Transform Infrared Attenuated Total Reflectance (FTIR-ATR) spectroscopy, which enables determination of primary peroxidation products. We examined the influence of the amount of hydrogen peroxide added to lipid suspension that was earlier extracted from plasma specimen on lipid peroxidation with use of TBARS and FTIR-ATR methods. Linear correlation between these methods was shown. The proposed method was effective during the evaluation of changes in the extent of lipid peroxidation in plasma during a haemodialysis in sheep. A measurement using the FTIR-ATR showed an increase in plasma lipid peroxidation after 15 and 240 minutes of treatment, while the TBARS concentration was respectively lower.

Galanin and vasopressin response to hyperosmotic stimulation: in vitro study.

Galanin (Gal)--a neuropeptide present in the nervous system and peripheral tissues--may be involved in the regulation of hypothalamo-neurohypophysial system function. It was shown that centrally injected galanin inhibits osmotically stimulated vasopressin (VP) secretion into the blood and reduces VP mRNA level in the supraoptic (SON) and paraventricular (PVN) hypothalamic nuclei. The aim of the present study in vitro was to investigate the influence of Gal on vasopressin release from isolated rat hypothalamus (Hth), neurohypophysis (NH) or hypothalamo-neurohypophysial explants (Hth-NH). The effect of Gal on VP secretion was studied under conditions of direct osmotic (i.e., Na⁺-evoked) (series 1) as well as nonosmotic (i.e., K⁺-evoked) (series 2) stimulation. In series 3, vasopressin response to Gal was studied using the neural tissues obtained from animals drinking 2 percent NaCl solution for eight days (indirect osmotic stimulation). Gal in a concentration of 10⁻¹° M and 10⁻8 M inhibited basal VP release from Hth, NH and Hth-NH explants isolated from euhydrated rats as well as from Hth-NH complex of osmotically challenged animals. When the neural tissues obtained from previously salt-loaded rats were incubated in K⁺-enriched medium the inhibitory effect of Gal was completely blocked. It may be concluded that the effect of Gal is depending on the current functional status of the hypothalamo-neurohypophysial system.

Predictors of depressive symptoms in patients with stroke - a three-month follow-up.

BACKGROUND AND PURPOSE: Depression is one of the most common post-stroke complications, which could impair rehabilitation outcome and quality of life, and could also increase mortality after stroke. The aim of the present study was to assess the association between demographic, socioeconomic and clinical (stroke risk factors, type of stroke, location of vascular lesion, cognitive functions) factors on the presence and severity of post-stroke depressive symptoms in patients after first ever stroke as well as on their social functioning. MATERIAL AND METHODS: A prospective, cohort study with a three-month observation period was performed in seven centres. Severity of depressive symptoms was assessed with the help of a short, 15-item version of the Geriatric Depression Scale (GDS), 3 months after stroke onset. RESULTS: On the basis of GDS (GDS L 5 points or > 5 points) patients were allocated to a group without (n = 160) or with symptoms suggestive of depression (n = 82). The study groups did not differ with respect to age, sex or place of residence. Univariate logistic regression analysis showed that independent predictors for the presence of symptoms suggestive of depression at 3 months after stroke were: low level of education, low income, greater severity of stroke, worse functional status, self-reported problems with daily-living activities and need of help in daily living activities. More than 60% of patients with depressive symptoms limited their social contacts. Patients with depressive symptoms were unsatisfied with their relations with life partners and friends. CONCLUSIONS: Our study showed a complex aetiology of post-stroke depressive symptoms with an important role of socioeconomic factors. Depressive symptoms after stroke worsen existing health, social and economic problems, and cause social isolation of patients.

[Sensorineural hearing loss as a consequence of carbon monoxide intoxication]. / Niedosluch czuciowo-nerwowy jako nastepstwo zatrucia tlenkiem wegla.

The authors describe the case of acute carbon monoxide intoxication in a 19 year old female patient, which caused, among other symptoms, bilateral sensorineural hearing loss. The symptoms, diagnostic methods and treatment with a particular regard to audiological examination were presented. Pathomechanism of carbon monoxide intoxication was also discussed. Despite the treatment, the effects of therapy have not been satisfactory.