Reduction of hippocampal long-term potentiation in transgenic mice ectopically expressing the neural cell adhesion molecule L1 in astrocytes

The influence of the neural cell adhesion molecule L1 on hippocampal long-term potentiation (LTP) was investigated using transgenic mice ectopically expressing L1 in astrocytes (GFAP-L1). L1 is a member of the immunoglobulin superfamily of homophilic adhesion molecules predominantly expressed in neurones. Previously, it has been demonstrated that local application of L1 antibodies and recombinant L1 fragments impair the expression of LTP. Here, we show that LTP induced by theta-burst stimulation or by pairing presynaptic stimulation with postsynaptic depolarisation was strongly reduced in GFAP-L1 mice, whereas basal synaptic transmission, post-tetanic potentiation, and paired-pulse facilitation were not modified. These results further support the idea that L1 is involved in synaptic plasticity and suggest that adhesion molecule-dependent changes in synaptic morphology contribute to the expression of LTP. © 1996 Wiley-Liss, Inc.     

Attenuation of inflammation in streptozotocin-induced diabetic rabbits by Matricaria chamomilla oil: A focus on targeting NF- κ B and NLRP3 signaling pathways

Objectives: The present study was conducted to investigate the protective effects of chamomile oil from Matricaria chamomilla against type 1 diabetes mellitus(T1 DM) and its potential mechanisms.Methods: T1 DM was established in male New Zealand white rabbits via a single intraperitoneal infusion of streptozotocin(STZ)(80 mg/kg body weight-1, dissolved in 0.2 m L of normal saline). Different doses of chamomile oil(25, 50 and 100 mg/kg) were orally administrated to STZ induced diabetic rabbits for 21 consecutive days. The expression of pro-inflammatory cytokines was determined using ELISA assay. The expression of NF-κB and NLRP3 was measured using Western blot assay.Results: Compared with normal rabbits, STZ-induced diabetic rabbits exhibited significant increased levels of blood glucose and decreased levels of serum insulin that were reversed using middle and high tested dose of chamomile oil. Likewise, STZ-induced diabetic rabbits showed a significant increased expression of NF-κB and NLRP3 proteins in the pancreas tissue that was reversed by high tested dose of chamomile oil.Conclusion: Collectively, our findings demonstrated that chamomile oil possesses anti-hyperglycemic, and anti-inflammatory activities in STZ-induced diabetic rabbits by targeting inflammatory cytokines and NF-κB and NLRP3 signaling pathways.     

Hereditary neuropathy with liability to pressure palsies

Journal of Neurology - Hereditary neuropathy with liability to pressure palsies (HNPP) is characterized by recurrent sensory and motor neuropathy in individual nerves starting in adolescence or...     

Intimate partner violence and subsequent depression and anxiety disorders

Social Psychiatry and Psychiatric Epidemiology - The current longitudinal study examines the temporal association between different types of intimate partner violence (IPV) at early adulthood...     

Challenges for the determination of spiramycin in aqueous matrices using LC-MS/MS: evidence for the solvent intrusion on the molecule integrity

Liquid chromatography-tandem mass spectroscopy (LC-MS/MS) is an accurate and specific technique for drug residue analysis in different matrices. The high specificity and sensitivity of the multiple reaction monitoring (MRM) approach for detecting drugs such as aldehydes, which have the potential to change mass during the sample preparation phase, becomes a drawback during the analysis process. In this study, concerns about the intrusion of solvent molecules into spiramycin''s chemical structure as an aldehydic drug as well as the stability of spiramycin in the milk matrix were addressed. Furthermore, the binding sites where the solvent molecules could bind to spiramycin molecules were investigated through nuclear magnetic resonance (NMR) spectroscopy. It was revealed that water, ethanol, and methanol as protic solvents can add to the formyl group of spiramycin molecules during standard solutions preparation while there was no evidence for the addition of acetonitrile and dimethyl sulfoxide (aprotic solvents). In addition, as time passed, the peak area of spiramycin decreased either in the spiked aqueous sample or milk sample while an increase in the peak area of H₂O-bound spiramycin was observed. After 96 h, more than 90% of spiramycin was converted to H₂O-bound spiramycin. In conclusion, we can propose the use of aprotic solvents for the preparation of spiramycin standard solutions especially when the prepared solutions are not used instantly. Moreover, ion transitions for both spiramycin and its H₂O-added form (843.6 m/z to 173.9 m/z and 861.5 m/z to 173.9 m/z, respectively) should be considered for the accurate quantification of spiramycin residue in aqueous samples such as milk.

Water, ethanol, and methanol as protic solvents can add to the formyl group of spiramycin molecules during standard solutions preparation while there was no evidence for the addition of acetonitrile and dimethyl sulfoxide as aprotic solvents.