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关键词： Caulerpa lentillifera   Dehydration   Biochemical composition   Antioxidant system   Photophysiology  

摘要： Caulerpa lentillifera is an economically important macroalgae. Many parental algae are needed in the commercial cultivation of C. lentillifera, and these algae are normally transported under dehydration. This study aimed to clarify the biochemical and photophysiological responses to dehydration stress to provide a theoretical basis for C. lentillifera transportation. The various biochemical and photophysiological changes to C. lentillifera were characterized during various lengths of dehydration stress. The relative water loss varied between 1.4% and 4.9% during dehydration periods of 2-120 h. Compared to the control, the contents of malondialdehyde, su-peroxide anion, and hydrogen peroxide during dehydration for 6-120 h increased significantly. Moreover, the chlorophyll fluorescence parameters (maximal photochemical efficiency of photosystem II, saturated photo-synthetically active radiation, relative electron transport rate, and initial slope of rapid light curve) and the contents of chlorophyll a and soluble protein all decreased with increasing dehydration duration. These results suggest that dehydration could lead to oxidative stress in C. lentillifera. Compared to the control, the content of soluble polysaccharide and the activities of antioxidant enzymes (peroxidase, superoxide dismutase, and cata-lase) were both substantially enhanced at a certain stage of dehydration, and the proline content was relatively higher during all dehydration periods, indicating that these compounds probably play a crucial role in defensive reactions against dehydration-induced oxidative stress in C. lentillifera. After recovery for 72 h, the vegetative reproductive capability of C. lentillifera with a dehydration duration of 2-24 h was not significantly different from that of the control. Based on the above results, a reasonable strategy of maintaining dehydration within 24 h was proposed for C. lentillifera transportation. Moreover, photoinhibition easily occurs in C. lentillife

关键词： Interdigitated electrodes   Metallization ratio   Crosstalk   Electrochemical impedance spectroscopy   Adaptive mesh refinement  

摘要： This paper investigates the effect of metallization ratio and side shift on the performance of interdigitated electrodes (IDEs). The IDEs were modelled using normal mesh and adaptive mesh refinement techniques to investigate the modelling error. The performance parameters such as electric field distribution, crosstalk and penetration depth of IDEs and the phenomenon of impedance biosensor based on surface conductivity model was simulated using COMSOL Multiphysics software. A detailed analysis was carried out to see the effect of metallization ratio on these performance parameters. In the simulation, the metallization ratio of IDEs was varied between 0.2-0.9, and the variation in side shift was 1-50 mu m. A significant reduction in modelling error was obtained for adaptive mesh refinement (AMR) based IDEs model. The IDEs with metallization ratio 0.7 and side shift between 10-20 mu m have shown higher measurement sensitivity. For validation of simulation results, experiments were conducted on fabricated IDEs with different metallization ratios. IDEs with metallization ratios 0.3, 0.5 and 0.7 were fabricated using PCB technology. The impedance spectra were obtained for a 10-100 mM KCl solution using electrochemical impedance spectroscopy (EIS). Through simulation and from experimental results, higher measurement sensitivity from IDEs was obtained at 0.7 metallization ratio. Finally, this paper demonstrates the importance of metallization ratio and side shift to ensure higher measurement sensitivity from IDEs when used for biochemical sensing applications. Graphic abstract

关键词： Span 60   Elastic vesicles   Ethanol injection   Buccal mucosa   Permeation   Edge activator  

摘要： The purpose of this investigation was to encapsulate carvedilol, a model beta-blocker antihypertensive into nano-spanlastics, followed by incorporation into 1% CMC wafer to afford a mucoadhesive buccal drug delivery system, targeting to sidestep the first-pass metabolism, improving the drug absorption and pharmacological effect, achieving non-invasive buccal delivery for treating hypertension. Carvedilol-loaded nano-spanlastics were rendered by ethanol injection technique, using 2(3)factorial design. The effect of formulation variables was investigated on nano-spanlastic characteristics. The optimal nano-spanlastic formulation (S2;containing 20% Brij 97) exhibited particle size (239.8 +/- 5 nm), entrapment efficiency (98. 16 +/- 1.44%), deformability index (8.74 +/- 0.42 g), and the flux after 24 h (J(max)) (22.5 +/- 0.25 (mu g/cm(2)/h) with enhancement ratio 2.87 as well as excellent stability after storage. Permeation study verified the preeminence of the S2 formula. A confocal laser scanning microscope showed deep penetration of S2 through sheep buccal mucosa formula compared to rhodamine B solution. S2-based wafer showed acceptable characters (pH, swelling, drug content, residence time, and release rate). In vivo studies (pharmacodynamic study and biochemical evaluation) showed considerable improvement in blood pressure, the profile of the lipid, oxidant stress biomarkers, and cardiac markers. Histopathological studies revealed the superiority of S2 wafer in the protection of heart tissues over Carvid (R). The results achieved indicate that nano-spanlastic-based wafer offers a promising improving trans-buccal carvedilol delivery system. Graphical abstract

关键词： Electrical stimulation   Inflammation   Vitreous fluid   Lipids   Lysophosphatidylcholine   Cytokines  

摘要： Electrical stimulation (ES) of the eye represents a therapeutic approach in various clinical applications ranging from retinal dystrophies, age-related macular degeneration, retinal artery occlusion and nonarteritic ischemic optic neuropathy. In clinical practice, ES of the eye is mainly performed with a transcorneal or transpalpebral approach. These procedures are non-invasive and well-tolerated by the patients, reporting only minimal and transient adverse events, while serious adverse effects were not observed. Despite the growing literature on animal models, only clinical parameters have been investigated in humans and few data are available about biochemical changes induced by ES of the eye. The purpose of this study is to investigate the possible mechanism that regulates the beneficial effects of ES on retinal cells function and survival in humans. 28 patients undergoing pars plana vitrectomy (PPV) for idiopathic epiretinal membrane (iERM) were randomly divided in two groups: 13 patients were treated with transpalpebral ES before surgery and 15 underwent surgery with no prior treatment. Vitreous samples were collected for biochemical analysis during PPV. ES treatment leads to a reduction in the vitreous expression of both proinflammatory cytokines, namely IL-6 and IL-8, and proinflammatory lipid mediators, such as lysophosphatidylcholine. Indeed, we observed a 70% decrease of lysophosphatidylcholine 18:0, which has been proven to exert the greatest proinflammatory activities among the lysophosphatidylcholine class. The content of triglycerides is also affected and significantly decreased following ES application. The vitreous composition of patients undergoing PPV for iERM displays significant changes following ES treatment. Proinflammatory cytokines and bioactive lipid mediators expression decreases, suggesting an overall antiinflammatory potential of ES. The investigation of the mechanism by which this treatment alters the retinal neurons leading to good outc

关键词： Infertility   Kigelia africana   Metoclopramide   Prolactin  

摘要： To study the biochemical and hormonal parameters in metoclopramide-induced hyperprolactinemic female Wistar rats administered ethanol leaf extract of Kigelia africana. Thirty (30) female Wistar rats were grouped into two major parts: (i) normal control (n = 5) and (ii) experimental (n = 25) to induce hyperprolactinemia. The experimental group was divided into five groups of five animals each, given a total of six in all. Group 1 received the distilled water alone, group 2 was metoclopramide-induced hyperprolactinemic rats only, group 3 comprised metoclopramide-induced hyperprolactinemic rats administered bromocriptine (2.5 mg Kg^–1 ***.), and groups 4–6 were metoclopramide-induced hyperprolactinemic rats administered 100, 200, and 400 mg Kg^–1K. africana ethanol extract, respectively. After treatments, biochemical and hormonal parameters were determined. Prolactin level increased significantly (P < 0.05) in the experimental groups and reduced following administration of various concentrations of K. africana extract (100, 200, and 400 mg Kg^–1 ***.) and bromocriptine than the normal control and hyperprolactinemic control groups. Significant increase (P < 0.05) in progesterone, luteinizing hormone follicle-stimulating hormone, and estradiol serum levels were observed at 400 mg Kg^–1 ***. of the extract as against the normal control. Similarly, bromocriptine (2.5 mg Kg^–1 ***.) produced the same effect. Non-significant increase (P > 0.05) of cholesterol and protein uteri levels were obtained in experimental rats treated with K. africana extract in comparison with the normal control and hyperprolactinemia control. In conclusion, ethanol extract of the plant can ameliorate hyperprolactinemia in rats and could improve some fertility hormones through its stimulatory effect on the gonads. © 2021, The Author(s), under exclusive licence to Springer-Verlag London Ltd. part of Springer Nature.

关键词： Leishmania braziliensis   Methylene blue   Photodynamic therapy   FTIR spectroscopy  

摘要： Photodynamic therapy (PDT) with photosensitizer methylene blue was applied toLeishmania braziliensis, and Fourier transform infrared (FTIR) spectroscopy was used to study biochemical changes in the parasite after PDT in comparison to untreated (C), only irradiation (I), and only photosensitizer (PS). Spectral analysis suggests increase in lipids, proteins, and protein secondary structures in PDT compared with C and decrease in nucleic acids and carbohydrates. Interestingly, these trends are different from PDT ofLeishmania majorspecies, wherein lipids decrease;there are minimal changes in secondary structures and increase in nucleic acids and carbohydrates. The study thus suggests possibility of different biomolecular players/pathways in PDT-induced death ofL. braziliensisandL. major.

关键词： Benthic invertebrate   Life cycle   Liquid chromatography-mass spectrometry   Fatty acid metabolite   Eicosanoid   Biomarker   Variation  

摘要： Aquatic pollution resulting from anthropogenic activities requires adequate environmental monitoring strategies in sentinel organisms. Thus, biochemical biomarkers have been used as early-warning tools of biological effects in aquatic organisms. However, before using these markers for environmental monitoring, knowledge about their developmental variation is vital. In this study, we assessed baseline levels and developmental variations of a group of potential biomarkers, oxylipins, during the lifespan of the Northern damselfly (Coenagrion hastulatum) using liquid chromatography-tandem mass spectrometry. Effects of wastewater exposure on baseline levels were studied in a subset of damselflies to investigate the responsiveness due to anthropogenic pollution. Thirty-eight oxylipins deriving from four polyunsaturated fatty acids via two enzymatic pathways were detected in damselflies at three larval stages and in the adult form. Overall, oxylipin baseline levels showed developmental variation, which was lowest in the intermediate larval stages. Effects of exposure to wastewater effluent on oxylipin baseline levels were dependent on the life stage and were greatest in the early and intermediate larval stages. The study provides first insights into oxylipin profiles of damselflies at different stages of development and their developmental variation. Based on our results, we propose further strategies for incorporating oxylipins in damselfly larvae as biochemical markers for anthropogenic pollution.

关键词： brain   blood-brain barrier   stress   neurodegeneration  

摘要： Blood-brain barrier (BBB) is a structural and functional element of the neurovascular unit (NVU), which includes cells of neuronal, glial, and endothelial nature. The main functions of NVU include maintenance of the control of metabolism and chemical homeostasis in the brain tissue, ensuring adequate blood flow in active regions, regulation of neuroplasticity processes, which is realized through intercellular interactions under normal conditions, under stress, in neurodegeneration, neuroinfection, and neurodevelopmental diseases. Current versions of the BBB and NVU models, static and dynamic, have significantly expanded research capabilities, but a number of issues remain unresolved, in particular, personification of the models for a patient. In addition, application of both static and dynamic models has an important problem associated with the difficulty in reproducing pathophysiological mechanisms responsible for the damage of the structural and functional integrity of the barrier in the diseases of the central nervous system. More knowledge on the cellular and molecular mechanisms of BBB and NVU damage in pathology is required to solve this problem. This review discusses current state of the cellular and molecular mechanisms that control BBB permeability, pathobiochemical mechanisms and manifestations of BBB breakdown in stress and neurodegenerative diseases, as well as the problems and prospects of creating in vitro BBB and NVU models for translational studies in neurology and neuropharmacology. Deciphering BBB (patho)physiology will open up new opportunities for further development in the related areas of medicine such as regenerative medicine, neuropharmacology, and neurorehabilitation.

关键词： Gastric tissue   Diabetes mellitus   Zinc   Glycoprotein   Oxidative stress  

摘要： The stomach is among the organs grossly affected organ by diabetic complications. The present study was aimed at investigating the protective role of zinc on stomach of streptozotocin (STZ)-induced diabetes mellitus. Female Swiss albino rats were divided in four experimental groups: Group I, control;group II, control + zinc sulfate;group III, STZ-induced diabetic animals;and group IV, STZ-diabetic + zinc sulfate. Diabetes was induced by intraperitoneal injection of STZ, at a dose of 65 mg/kg body weight. Zinc sulfate (100 mg/kg body weight) was given daily by gavage for 60 days to groups II and IV. At the end of the experiment, the rats were sacrificed, and the tissues were taken. In the diabetic group, hexose, hexosamine, fucose, and sialic acid levels, as well as tissue factor, adenosine deaminase, carbonic anhydrase, xanthine oxidase, lactate dehydrogenase, prolidase activities, advanced oxidized protein products, homocysteine, and TNF-alpha levels were increased in the stomach tissue homogenates. Whereas, catalase, superoxide dismutase, glutathione-S-transferase, glutathione peroxidase, glutathione reductase, paraoxonase, and aryl esterase activities were decreased in the diabetic group. The administration of zinc reversed all the deformities. These findings suggest that zinc has protective role in ameliorating several mechanisms of STZ-induced diabetic stomach injury.

关键词： Arthrocenmum macrostachyum   Photosynthetic pigments   Osmolytes   Protein patterns   Salinity   Soybean  

摘要： A pot experiment was carried out to study the ameliorative role of foliar application of an extract of the halophyteArthrocnemum macrostachyum(A. macrostachyum)on soybean (Glycin maxL.) plants grown under salinity stress (0, 75, and 150 mM NaCl). Growth traits, content of photosynthetic pigments, osmolytes, ascorbic acid and total phenol, oxidative damage, and proteins pattern were determined. Growth parameters of soybean plants grown under both saline regimes (75 and 150 mM NaCl) were reduced except for the response to the foliar application ofA. macrostachyumextract in either stressed or non-stressed plants. Foliar application ofA. macrostachyumextract reinforced the photosynthetic pigment, soluble sugars, and soluble proteins content. Besides, it also minimized the negative impacts of salinity on soybean plants by decreasing the content of malondialdehyde (MDA) and hydrogen peroxide (H2O2). The results herein showed that the plant water extract and their interactions in the two NaCl levels increased the proline, total free amino acids, total phenols, and ascorbic acid content. Protein patterns in soybean leaves indicated protein expression suppression in soybean plants irrigated with 150 mM NaCl. The magnitude of suppression caused by the saline level was enhanced by usingA. macrostachyumextract. The findings of this study indicate that the use of an extract of the halophyteA. macrostachyumcan be considered as an unconventional and novel tool in the mitigation of salinity stress.