Fluorinated polyurethanes with a glass transition temperature as low as -139 °C and a decomposition onset temperature of 247-330 °C were prepared by a reaction of fluorinated alcohols with aromatic ...and cycloaliphatic diisocyanates in solution or melt.
Background. Context is the essential tool to connect the sentences in the text. The formalization of the context relations has been well considered for cohesion. However, the role of coherence in the ...context relations requires its studying. Since both kinds of the linkage participate in the forming the context relations there is a need to develop a system of analysis of context which considers both categories of textuality. There is in pragmatics different approaches to examine contexts. In the article is given a short analysis of the minimalists and contextualists approaches. It is shown that contextualists approach fits more for the text analysis.
Materials and methods. The research material comprises fragments of fiction and non-fiction texts containing clearly manifested context relations. Methods used – discourse analysis, classification.
Purpose. To establish specificity of the cohesive and coherence connections between the sentences linked by means of the context relations.
Results. Contextual relations are defined as relations between base of the context and the context. Base of context are context sensitive expressions and parts of sentence obtained context sensitivity in some conditions. The selected texts illustrate that context relations are manifested to a greater or lesser extent depending on context sensitivity of the base of context. A pattern has been revealed that the importance of coherence increases as the level of the context sensitivity while reducing the level of the context sensitivity or vice versa.
Early detection of microangiopathic complications of diabetes mellitus (DM) is necessary to analyze the patient's condition and prevent disease progression. The study was aimed to investigate the ...relationship between the presence of retinopathy and decreased reactivity of the microcirculatory bed in patients with diabetes.
The study involved 130 subjects: healthy volunteers (n = 48), DM patients without retinopathy (n = 53) and with retinopathy (n = 29). Skin microvascular reactivity was assessed on the forearm using laser Doppler flowmetry with a local heating test combined with occlusion.
The slope of local thermal hyperemia curve (Slope-120) and other parameters of microvascular reactivity showed difference in pairwise comparisons between the groups. Slope-120 had the highest sensitivity (0.759) and specificity (0.717) in detection of diabetic retinopathy. The decrease of Slope-120 was associated with retinopathy (odds ratio (OR) – 8.3 (2.9–24.1), p < 0.001), even after adjusting for other factors (OR – 11.0 (1.6–77.2), p = 0.016).
Thus, assessment of skin microvascular reactivity may be a useful test for detecting signs of microangiopathic complications and for screening patients in risk group. Decreased microvascular reactivity has been shown to be prospective as an independent indicator of retinopathy in type 1 DM.
•The diabetic microangiopathic changes occur in many organs and lead to complications.•The skin microcirculation can reflect signs of diabetes and diabetic complications.•In our study, decreased skin microvascular reactivity was associated with retinopathy.•It can be used as an independent risk factor for diabetic retinopathy presence.
Introduction
The development of new highly accurate, inexpensive and accessible methods for the detection of lower-extremity peripheral artery disease (LE-PAD) in diabetic patients is required. The ...aim of this study was to evaluate the accuracy of a new incoherent optical fluctuation flowmetry (IOFF) method in detecting legs with hemodynamically significant stenoses compared to ankle brachial index (ABI) and transcutaneous oximetry (TcPO2) in patients with diabetes mellitus (DM).
Materials and methods
Patients were recruited into 2 groups. Group 1 included patients with DM without LE-PAD and/or diabetic foot syndrome; Group 2 included patients with DM and LE-PAD. All patients underwent the following measurements: ultrasound (reference method), ABI, TcPO2, and the new IOFF method.
Results
The new IOFF method showed a sensitivity of 79.5% and a specificity of 89.8% in detecting limbs with hemodynamically significant stenosis (AUC 0.890, CI 0.822–0.957). TcpO2 allows the diagnosis of LE-PAD with 69.2% sensitivity and 86.2% specificity (AUC 0.817, CI 0.723–0.911). Using a standard ABI cut-off of less than 0.9, the sensitivity and specificity for this parameter were 34.5% and 89.7%, respectively. Increasing the diagnostic cut-off of the ABI on the study group to 0.99 improved sensitivity to 84.6% and specificity to 78% (AUC,0.824 CI 0.732–0.915).
Conclusions
The new IOFF technique has demonstrated high sensitivity and specificity in the detection of LE-PAD in patients with DM. The high accuracy, rapid measurement, and potential availability suggest that the new IOFF method has a high potential for clinical application in the detection of PAD.
The aim of the present study was to evaluate changes in cutaneous blood flow detected by incoherent optical fluctuation flowmetry (IOFF) in diabetic patients with diagnosed microangiopathies. The ...study includes 52 patients with type 2 diabetes mellitus (12 males, 40 females, median age 57 (51; 60) years). All patients were examined using the IOFF method using functional tests: occlusion test on the index finger, local heat test on the dorsum of the foot, and local heat test on the big toe. The patients were divided into 2 groups: 13 patients with both diabetic retinopathy and diabetic nephropathy (Group 2, severe microcirculatory disorders) and 39 patients with only 1 microangiopathic complication or without any (Group 1). Local thermal hyperaemia (LTH2_1) was higher in Group 1 than in Group 2 (p = 0.011). Post-occlusive reactive hyperaemia (PORH_2) was higher in Group 2 than in Group 1 (p = 0.009). No changes were detected on the big toe. When PORH_2 and LTH2_1 were used in combination, the area under the ROC curve (95% CI) was 0.733 (0.62 to 0.846). Thus, the IOFF method has the potential to accurately detect blood flow abnormalities associated with diabetic microangiopathies.
BACKGROUND: Neurogenic regulation is involved in the development of microcirculation response to local heating. We suggest that microvascular reactivity can be used to estimate the severity of ...diabetic polyneuropathy (DPN). OBJECTIVE: To evaluate the prospects for using the parameters of skin microvascular reactivity to determine the severity of DPN. METHODS: 26 patients with diabetes mellitus were included in the study (patients with retinopathy (n = 15), and without retinopathy (n = 11)). The severity of DPN was assessed using Michigan Neuropathy Screening Instrument (MNSI) and Norfolk QOL-DN (NQOLDN). Skin microcirculation was measured by laser Doppler flowmetry with local heating test. RESULTS: There were revealed moderate negative correlations between microvascular reactivity and the severity of DPN (for MNSI (Rs = –0.430), for NQOLDN (Rs = –0.396)). In patients with retinopathy, correlations were stronger than in the general group (for MNSI (Rs = –0.770) and NQOLDN (Rs = –0.636)). No such correlations were found in patients without retinopathy. CONCLUSION: Correlation of the microvascular reactivity and DPN was revealed in patients with registered structural disorders in microvessels (retinopathy). The lack of such correlation in patients without retinopathy may be explained by the intact compensatory mechanisms of microvessels without severe disorders.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Keloid scars, in contrast to other scar types, significantly reduce the patient's quality of life. To develop a nondestructive optical diagnostic technique predicting the keloid scars formation
, ...laser-induced fluorescence spectroscopy (LFS) was used to study the autofluorescence in skin of patients with various types of head and neck cicatricial deformities. The unexpected results were obtained for the endogenous fluorescence of lipofuscin. Significantly reduced autofluorescence of lipofuscin was registered both in the intact and in the keloid scar tissues in comparison with the intact and scar tissues in patients with hypertrophic and normotrophic scars. Sensitivity and specificity achieved by LFS in keloid diagnosis are 81.8% and 93.9% respectively. It could take place due to the changes in the reductive-oxidative balance in cells, as well as due to the proteolysis processes violation. Therefore, we suppose that the evaluation of the lipofuscin autofluorescence in skin before any surgical intervention could predict the probability of the subsequent keloid scars formation.
(1) Background: To date, there are no studies evaluating the ability of the incoherent optical fluctuation flowmetry (IOFF) method to assess foot tissue perfusion. The aim of this study was to ...evaluate the correlation between perfusion values measured by IOFF and TcPO2 in patients with diabetes-related lower-extremity complications. (2) Methods: This was an observational, cross-sectional, two-center study. Diabetic patients with peripheral artery disease and/or diabetic foot ulcers were studied (n = 27, examinations were carried out on 54 legs). Perfusion in the foot tissues was assessed using TcPO2 (reference standard for this study) and the IOFF method. (3) Results: High correlation coefficients of all perfusion parameters measured by IOFF with TcPO2 (Rs 0.7 to 0.76) were shown. The study demonstrated that the IOFF method allows, with a sensitivity of 85.7% and a specificity of 90.0%, the identification of patients with a critical decrease in TcPO2 < 20 mmHg. (4) Conclusions: The high correlation of IOFF parameters with TcPO2 and the moderately high sensitivity and specificity in detecting patients with severe ischemia of foot tissues shows the promise of the method for assessing a tissue perfusion in patients with diabetes-related lower-extremity complications.
Background: This paper demonstrates the use of optical diagnostic methods to assess the dynamic skin changes observed in acute and chronic exposure to ultraviolet (UV) radiation in vivo. Methods: ...Firstly, in order to initiate photoaging (chronic UV exposure), animals (n = 40) were divided into two groups: chronic UV exposure (n = 30), and control (n = 10; without irradiation). Photoaging in animals was induced by chronic repeated exposure to UVA radiation three times per week, for 12 weeks continuously, while the UV dose increased stepwise over the course of the experiment (55 minimal erythema doses (MED) in total). Laser fluorescence spectroscopy (LFS), optical tissue oximetry (OTO), laser Doppler flowmetry (LDF), and optical coherence tomography (OCT) of the shaved dorsum skin were performed regularly, once per week until the conclusion of the study. At 0, 5, and 12 weeks of the experiment, histological examination of animal tissues using hematoxylin/eosin and Masson’s trichrome staining was performed. At the second stage, erythema was induced in mice (n = 15) by acute UV exposure at high doses. The colorimetric assay of the image from a digital RGB camera was used to evaluate the erythema index. Results: The tissue content index ηcollagen of collagen was appropriate for the characterization of skin photoaging. Significant differences (p < 0.05) in ηcollagen were found between the control and photoaging groups from the 5th to the 9th week of the experiment. In addition, the rate of collagen degradation in the control group was about half that of the photoaging group. This marker allows the differentiation of photo- and chronoaging. OCT revealed the main optical layers of the skin in compliance with the histological pattern. The analysis of the RGB camera images provided visualization of the acute skin reaction to UV radiation. Conclusions: This study demonstrates the applicability of optical methods for the quantitative assessment of acute and chronic skin effects of UV exposure in vivo.
SITUATIONALITY AS A BASIS OF TEXT COHERENCE Glazkov, Alexey V.
Vestnik Moskovskogo gosudarstvennogo oblastnogo universiteta. Serii͡a︡ "Russkai͡a︡ filologii͡a︡",
2022
1
Journal Article
PDF
