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Purpose: To assess the Pictor Plus portable noncontact ophthalmic camera for use in diagnosis of severe retinopathy of prematurity (ROP) and its feasibility for telemedicine applications, especially in developing countries., Methods: A cross-sectional study was conducted from April 2018 to December 2019 in six public neonatal care centers in the state of Rio de Janeiro. Observer 1 performed the examination with a binocular indirect ophthalmoscope and subsequently captured a digital image using the Pictor Plus camera. These images were analyzed by observers 2 and 3, who were masked to the results recorded by observer 1., Results: The convenience sample was 200 premature newborns (n = 712 eyes) with a birthweight of ≤1,500 g or gestational age at birth of ≤32 weeks. The sensitivity of Pictor Plus digital images for the diagnosis of plus or pre-plus disease was 65.8% for observer 2 and 63.2% for observer 3; the specificity, 100% and 98,4%, respectively. Interobserver agreement analysis for image reading compared to observer 1 indirect ophthalmoscopy showed kappa coefficients of 0.77 (observer 2) and 0.68 (observer 3)., Conclusions: In our study cohort, the Pictor Plus, a relatively low-cost camera, was effective in facilitating accurate diagnosis of ROP., (Copyright © 2022 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.)

The aim of this study was to determine the effect of an extremely low-frequency magnetic field (ELFMF) on the production of liver fluke larvae in a parasite-host system: Fasciola hepatica--Galba truncatula. Both F. hepatica eggs and F. hepatica-infected snails were exposed to an ELFMF (50 Hz, 2.0 mT) for 14 days and 36 days, respectively. F. hepatica-infected snails were divided into 4 groups, 10 specimens each. The snails of groups I and II were infected with F. hepatica larvae--miracidia obtained from control cultures, while the snails of groups III and IV were infected with miracidia reared from eggs that had been incubated in an ELFMF. After infection, the snails of groups II and IV were placed in an ELFMF, while those of groups I (control) and III were housed outside the ELFMF. At 36 days post-infection (dpi) there were no statistically significant differences between the number of F. hepatica larvae--cercariae and metacercariae, obtained from G. truncatula snails in the control group (group I) and the snail groups exposed to ELFMF (groups II, III and IV). However, a statistically significant difference between the average number of F. hepatica larvae in snail groups III and IV may indicate that the duration of exposure to ELFMF, i.e. embryogenesis period vs. the entire larval development, played a role in the production of F. hepatica larvae, and resulted in a reduction of their number.

Eggs of Fasciola hepatica were exposed for 10 days to extremely low frequency magnetic field (ELFMF) at the frequency of 50 Hz and density of 2 mT (rms). The results show an accelerated hatching of F. hepatica eggs in relation to control (non-exposed) group. The host snails, Lymnaea truncatula, were divided into three groups; those of groups I and II were infected with the miracidia of F. hepatica hatched from control egg culture, whereas those of group III were infected with miracidia hatched from eggs affected by ELFMF. Thereafter, snails of groups II and III were exposed to ELFMF for 53 days, whereas those of group I were not exposed. At day 14 post infection, a significant decrease was observed in the number of cocoons laid by snails of group III, compared with control. Also, significant mortality in group III snails was observed 42 days post infection. The increased mortality and a lower number of cocoons laid by group III snails have probably resulted from enhanced stimulation of metacercarial parthenogenetic reproduction in consequence of infecting the molluscs with miracidia reared under ELFMF.

The aim of this study was to determine the effects of an extremely low-frequency 50 Hz magnetic field (ELFMF) on the oviposition and development of Drosophila melanogaster. The results show that exposure of D. melanogaster females of generation P and all the development stages of generation F1 to an ELFMF weakened the oviposition of these insects in their subsequent generations.

Introduction: To estimate the in vitro level of L-ascorbic acid radical in lenses of patients with senile or diabetic cataract using EPR (Electron Paramagnetic Resonance) spectroscopy., Material and Methods: 24 human cataractous nuclei obtained during extracapsular removal were used. 5 of them (21%) were from diabetic patients. The analysis was carried out at the Department of Medical Physics of the Pomeranian Medical University using EPR spectroscopy. The in vitro level of L-ascorbic acid radical was calculated as the number of unpaired spins in the lens calculated in units x 10(16)/gram (spin/g), which is proportional to the in vivo level of vitamin C in lenses., Results: The average L-ascorbic acid radical level in lenses of diabetic patients amounted 0.53 x 10(16) spin/g +/- 0.22 x 10(16) spin/g, and was lower than in group of non-diabetic patients in which it ranged 0.87 x 10(16) spin/g +/- 0.31 x 10(16) spin/g (p = 0.036). There was no significant correlation between L-ascorbic acid radical level and sex, age or visual acuity in these two groups of patients., Conclusions: (1) EPR spectroscopy can be used to determine the in vitro level of L-ascorbic acid radical in human lenses. (2) The in vitro L-ascorbic acid radical level in cataract lenses of patients with diabetes was lower than in patients without diabetes. (3). Lower in vitro level of L-ascorbic acid radical in lenses of patients with diabetes means lower in vivo level of vitamin C, what suggests an increased intensity of free radical reactions in the group of patients with diabetes than in the group without diabetes.

The hypothesis has been recently presented that lead may exert its negative effect at least partially through the increase of reactive oxygen species (ROS) level in tissues. However, little is known about the influence of lead intoxication on equilibrium between generation and elimination of ROS in the male reproductive system. Sexually mature male Wistar rats were given ad libitum 1% of aqueous solution of lead acetate (PbAc) for 9 months. Significantly higher lead concentrations were found in blood [median 7.03 (Q25-Q75: 2.99-7.65) versus 0.18 (0.12-0.99) microg dl-1, P < 0.01], caput epididymis [median 5.51 (Q25-Q75: 4.31-7.83) versus 0.51 (0.11-0.80) microg g-1 d.m., P < 0.001], cauda epididymis [median 5.88 (Q25-Q75: 4.06-8.37) versus 0.61 (0.2 - 1.08) microg g-1 d.m., P < 0.001] and testis [median 1.81 (Q25-Q75: 0.94-2.31) versus 0.17 (0.03-0.3) microg g-1 d.m., P < 0.01] of lead-intoxicated rats when compared to the control. The concentration of ascorbyl radical, generated in vitro from L: -ascorbic acid (present in tissues in vivo) was measured by means of Electron Paramagnetic Resonance (EPR) spectroscopy. The EPR signal of ascorbyl radical in caput epididymis, cauda epididymis, testis and liver of lead acetate-treated animals revealed a significant decrease by 53%, 45%, 40% and 69% versus control tissues, respectively. Plasma L: -ascorbic acid content measured by high performance liquid chromatography (HPLC) method and total antioxidant status (TAS) measured by means of spectrophotometry were also significantly lower in the intoxicated versus control animals (28% and 21%, respectively). In the group exposed to lead the concentration of lipid peroxide in homogenates of the reproductive system organs was significantly elevated versus control group. It can be assumed that the lower EPR signal was caused by decreased tissue concentrations of L: -ascorbic acid. The latter may have resulted from consumption of ascorbic acid for scavenging of ROS excess in tissues of animals chronically exposed to lead.

Fertilised Ascaris suum eggs were subjected to an alternating electromagnetic field of frequency 50 Hz and density 2 mT for 60 days. The developing embryos in both control and experimental cultures were examined daily under a microscope. The experiment resulted in an accelerated rate of embryogenesis in the eggs incubated in the electromagnetic field, higher rates of malformed embryos as well as much higher mortality rate of L2 larvae.

The ultra-weak light, chemiluminescence (CL), of stimulated leukocytes is a well-known phenomenon. Parameters of this CL are modified by many factors including laboratory procedures. The order of stimulation and enhancement (two possibilities) and two concentrations of luminol create four types of procedure, which were accomplished in five sample storage 'time points'. We received the strongest signals of CL using higher concentrations of luminol (and DMSO), but only when stimulation (FMLP) was used before enhancement (luminol); luminol used before FMLP strongly inhibited CL. For lower luminol concentration (and DMSO), the order of stimulation and enhancement was of no importance. There were comparable but weaker signals of CL in this case. We received stronger signals with storage time for all procedures. It may be dependent on the priming of phagocytes by releasing cell factors. Stimulation (FMLP) before enhancement (luminol) eliminates the inhibitory effect of DMSO on CL., (Copyright 2002 John Wiley & Sons, Ltd.)

Fluorine 19F is one of few 'lucky' elements found in living organisms, whose nucleus is characterised by non-zero spin, which makes it possible to detect fluorine and to analyse (and image) its chemical compounds with the help of Nuclear Magnetic Resonance (NMR). Fluorine 19F spectroscopy is not as popular as that of hydrogen 1H or phosphorus 31P, however, this method has recently been developed and applied (in medicine, too) more and more frequently, despite technical problems. This paper is a brief introduction to the techniques of investigating fluorine 19F with NMR spectroscopy, providing insight into the peculiarities and the difficulties associated with this method. It is also a short review of the achievements in NMR fluorine investigations in the fields of biology and medicine.

Eighteen children with steroid-sensitive nephrotic syndrome (SSNS) were studied. The control group comprised 20 healthy children. The following indirect parameters of reactive oxygen species activity were determined in nephrotic patients during four stages of the disease (full relapse before prednisone administration, disappearance of proteinuria, prednisone cessation, unmaintained remission): plasma malondialdehyde (MDA) levels, copper/zinc superoxide dismutase (CuZn SOD) activity and glutathione peroxidase (GPX) activity in erythrocytes, reduced glutathione (GSH) and vitamin C levels in whole blood, and vitamin E level in serum. Increased MDA levels, reduced vitamin C levels, and enhanced CuZn SOD activity were found in relapse. GSH concentration was high during all four stages. Vitamin E level was also increased, parallel to the pattern of serum lipids. GPX activity remained low during the proteinuria stage and in remission. We conclude that the majority of abnormal findings can be attributed to the hyperlipidemia of NS. Low GPX activity may be a factor limiting the antioxidant capacity in NS. The present study is inconclusive regarding the role of free radicals in the proteinuria of NS.

Ozone is one of the most potent toxic agents. The noxious effects of its influence on living organisms appear mainly in the lungs and blood. A considerable role in its action is ascribed to free radicals. In this study the ESR method was applied to indirectly demonstrate the free radical effects, as well as the significance of ascorbate in ozonizing the blood. The effects of ozonizing the blood in vitro indicate the existence of a "local" protective mechanism of the blood cells, while in vivo they point out the consumption of ascorbate in "scavenging" of free radicals.

The effect exerted on the ascorbate system due to the exposure of mice to the constant magnetic field associated with MRI methods has been examined. The mice were exposed to magnetic field 1.00 T strength for 0.2 h, 3 h, or 24 h. The ascorbyl free radical in tissues was measured in vitro, which in vivo corresponds to the level of ascorbic acid. Only in a group of mice where the ascorbyl free radical was measured 24 h following their exposure to magnetic field 1.00 T strength for 24 hours, was the level of free radical in tissues significantly decreased.

The objective of the paper was to investigate the changes in haemoglobin properties under the influence of ozone on haemolysates of erythrocytes. The detailed analysis of experiments permitted to draw the following conclusions: 1. Haemoglobin in the presence of ozone is transformed into methaemoglobin in a biphasic process. 2. In ozone exposed haemolysates of erythrocytes the haemoglobin had other properties: an increase in affinity for oxygen and a decrease of the hem-hem interaction coefficient.

There has been considerable recent interest in the question of effects of constant magnetic fields (CMF) on living organisms. The possible alteration of the physiochemical properties of water appears to be one example of such an influence. The dielectric constant, pH, and surface tension of water exposed to CMF action were studied. The results fail to confirm the changes observed by some authors. Controversial opinions on this problem are also summarized and discussed.