Over
the last 100–120 years, due to the ever-increasing
importance of fluorine-containing compounds in modern technology and
daily life, the explosive development of the fluorochemical industry
led to an enormous increase of emission of fluoride ions into the
biosphere. This made it more and more important to understand the
biological activities, metabolism, degradation, and possible environmental
hazards of such substances. This comprehensive and critical review
focuses on the effects of fluoride ions and organofluorine compounds
(mainly pharmaceuticals and agrochemicals) on human health and the
environment. To give a better overview, various connected topics are
also discussed: reasons and trends of the advance of fluorine-containing
pharmaceuticals and agrochemicals, metabolism of fluorinated drugs,
withdrawn fluorinated drugs, natural sources of organic and inorganic
fluorine compounds in the environment (including the biosphere), sources
of fluoride intake, and finally biomarkers of fluoride exposure.
The correlation between the helicity (absolute conformation) of the O-heterocyclic ring of chiral 2,3-dihydrobenzo[b]furan (1) and chromane (2) derivatives and their (1)L(b) band CD was investigated. The same helicity rule was found for both unsubstituted chromophores: P/M helicity of the heterocyclic ring leads to a negative/positive CD within the (1)L(b) band. While the substitution of the fused benzene ring by achiral substituents does not change this helicity rule for the chromane chromophore, it leads to its inversion for the 2,3-dihydrobenzo[b]furan chromophores. On the basis of these observations, the published absolute configurations of natural flavonol and pterocarpan derivatives were confirmed and the configurational assignments of several natural neolignans revised.
Stress is well-known to contribute to the development of both neurological and psychiatric diseases. While the role of the blood-brain barrier is increasingly recognized in the development of neurodegenerative disorders, such as Alzheimer's disease, dysfunction of the blood-brain barrier has been linked to stress-related psychiatric diseases only recently. In the present study the effects of restraint stress with different duration (1, 3, and 21 days) were investigated on the morphology of the blood-brain barrier in male adult Wistar rats. Frontal cortex and hippocampus sections were immunostained for markers of brain endothelial cells (claudin-5, occluding, and glucose transporter-1) and astroglia (GFAP). Staining pattern and intensity were visualized by confocal microscopy and evaluated by several types of image analysis. The ultrastructure of brain capillaries was investigated by electron microscopy. Morphological changes and intensity alterations in brain endothelial tight junction proteins claudin-5 and occludin were induced by stress. Following restraint stress significant increases in the fluorescence intensity of glucose transporter-1 were detected in brain endothelial cells in the frontal cortex and hippocampus. Significant reductions in GFAP fluorescence intensity were observed in the frontal cortex in all stress groups. As observed by electron microscopy, 1-day acute stress induced morphological changes indicating damage in capillary endothelial cells in both brain regions. After 21 days of stress thicker and irregular capillary basal membranes in the hippocampus and edema in astrocytes in both regions were seen. These findings indicate that stress exerts time-dependent changes in the staining pattern of tight junction proteins occludin, claudin-5, and glucose transporter-1 at the level of brain capillaries and in the ultrastructure of brain endothelial cells and astroglial endfeet, which may contribute to neurodegenerative processes, cognitive and behavioral dysfunctions.
Elevated serum triglyceride concentration (seTG, >1.7 mM or >150 mg/dL) or in other words hypertriglyceridemia (HTG) is common in the populations of developed countries. This condition is accompanied by an increased risk for various diseases, such as acute pancreatitis (AP). It has been proposed that HTG could also worsen the course of AP. Therefore, in this meta-analysis, we aimed to compare the effects of various seTGs on the severity, mortality, local and systemic complications of AP, and on intensive care unit admission. 16 eligible studies, including 11,965 patients were retrieved from PubMed and Embase. The results showed that HTG significantly elevated the odds ratio (OR = 1.72) for severe AP when compared to patients with normal seTG (<1.7 mM). Furthermore, a significantly higher occurrence of pancreatic necrosis, persistent organ failure and renal failure was observed in groups with HTG. The rates of complications and mortality for AP were significantly increased in patients with seTG >5.6 mM or >11.3 mM versus <5.6 mM or <11.3 mM, respectively. We conclude that the presence of HTG worsens the course and outcome of AP, but we found no significant difference in AP severity based on the extent of HTG.
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