Oxygen free radicals have been implicated in the pathogenesis of diabetic microangiopathy. The production of superoxide anion (O2-.) by polymorphonuclear leukocytes (PMNs) from 45 insulin-dependent diabetes mellitus patients in the resting state and in response to a soluble stimulus (phorbol myristate acetate) was measured spectrophotometrically and compared with that of 15 age and sex matched controls. The resting superoxide anion production by PMNs from diabetic patients was significantly higher than that of controls (2.17 +/- 1.32 and 1.35 +/- 0.6 nmol/10(5) cells/60 min respectively; p = 0.037). In contrast, PMNs from diabetic patients released significantly lower levels of superoxide anion compared to controls in response to phorbol myristate acetate stimulation (2.33 +/- 2.04 and 3.55 +/- 0.98 nmol/10(5) cells/60 min respectively; p = 0.044). The stimulated superoxide anion production was significantly higher in diabetic patients with retinopathy compared to diabetic patients without retinopathy (2.7 +/- 2.08 and 1.3 +/- 1.6 nmol/10(5) cells/60 min respectively; p = 0.02). Furthermore, stimulated PMNs from diabetic patients with proliferative retinopathy generated superoxide anion at significantly higher rates than did those from diabetics with nonproliferative retinopathy or without retinopathy (3.8 +/- 1.5, 2.08 +/- 2.1 and 1.3 +/- 1.6 nmol/10(5) cells/60 min respectively; p = 0.005). These results suggest that reactive oxygen species produced by PMNs may play a role in the progression of diabetic retinopathy.
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BMC Plant Biol
January 2025
College of Tobacco Science, Guizhou University, Guiyang, 550025, China.
Aquaporins are widely present in the plant kingdom and play important roles in plant response to abiotic adversity stresses such as water and temperature extremes. In this study, we investigated the regulatory role of NTPIP2;4 on drought tolerance in tobacco at physiological and transcriptional levels. In this experiment, we constructed an NtPIP2;4 overexpression vector and genetically transformed tobacco variety 'K326' to investigate the mechanism of NtPIP2;4 gene in regulating drought tolerance in tobacco at physiological and transcriptomic levels.
View Article and Find Full Text PDFPhysiol Rev
January 2025
Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA, 15261.
The redox signaling network in mammals has garnered enormous interest and taken on major biological significance in recent years as the scope of NADPH oxidases (NOXs) as regulators of physiological signaling and cellular degeneration has grown exponentially. All NOX subtypes have in common the capacity to generate reactive oxygen species (ROS) superoxide anion (O) and/or hydrogen peroxide (HO). A baseline, normal level of ROS formation supports a wide range of processes under physiological conditions.
View Article and Find Full Text PDFJ Environ Manage
January 2025
Department of Sanitary Engineering, Faculty of Civil and Environmental Engineering, Gdansk University of Technology, Narutowicza 11/12 Str., 80-233, Gdansk, Poland; School of Civil, Environmental, and Architectural Engineering, College of Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea. Electronic address:
Advanced Oxidation Processes (AOPs) have proven to be an effective solution for chemical wastewater treatment, particularly for degradation of organic pollutants, especially dyes. Ozonation is recognized as one of the most prevalent AOPs. Nevertheless, some cases show a lowered efficiency of O utilization which is attributed to its inadequate distribution in the treated water causing low residence time, low mass transfer coefficient as well as shorter half-life.
View Article and Find Full Text PDFFood Chem X
January 2025
College of Horticulture, Hebei Agricultural University, Baoding 071001, China.
Few studies have explored the impact of blue light-emitting diode (BL) irradiation combined with different storage temperatures on antioxidant defense and cell wall metabolic activities related to the quality deterioration of postharvest strawberries. This study investigates the effects of BL exposure as a non-chemical preservation strategy to improve the postharvest quality of strawberries stored at 22 °C and 8 °C. Over a 10-day storage period, BL irradiation significantly reduced respiratory and ethylene production rates, while preserving fruit firmness and increasing the contents of soluble sugar and total phenol at both temperatures.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Center for High Pressure Science & Technology Advanced Research (HPSTAR), Shanghai, 201203, P.R. China.
Under extreme conditions, condensed matters are subject to undergo a phase transition and there have been many attempts to find another form of hydroxide stabilized over HO. Here, using Density Functional Theory (DFT)-based crystal structure prediction including zero-point energy, it is that proton superoxide (HO), the lightest superoxide, can be stabilized energetically at high pressure and temperature conditions. HO is metallic at high pressure, which originates from the 𝜋 orbitals overlap between adjacent superoxide anions (O ).
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