Research suggests that thioether analogs of vitamin K (VK) can act to preserve the phosphorylation of epidermal growth factor receptors by blocking enzymes (phosphatases) responsible for their dephosphorylation. Additionally, these derivatives can induce apoptosis via mitogen-activated protein kinase and caspase-3 activation, inducing reactive oxygen species (ROS) production, and apoptosis. However, vitamin K exhibits only weak inhibition of phosphatase activity, while the ability of VK to cause oxidative DNA damage has raised concerns about carcinogenicity.
View Article and Find Full Text PDFIntroduction: Although several approaches for approximating daily Na intake and the Na/K ratio using casual urine are available, the most useful method remains unclear during daily practice and at home.
Methods: Twenty-seven participants measured their casual urinary Na/K ratio repeatedly using a Na/K ratio monitor and also measured overnight urine once daily using a monitoring device which delivers on-site feedback to estimate their salt intake under unrestricted, low-salt (LS) (6 g/day), and high-salt (HS) (12 g/day) diets.
Results: The monitoring method utilizing overnight urine to estimate daily Na remained insensitive, resulting in significant overestimation during the LS diet and underestimation during the HS diet periods; estimated salt intake during the LS and HS diet periods plateaued at 7-8 g/day and 9-10 g/day within 3 day; mean estimated salt intake was 11.
Superoxide dismutase 1 (SOD1) is a metalloenzyme with high structural stability, but a lack of Cu and Zn ions decreases its stability and enhances the likelihood of misfolding, which is a pathological hallmark of amyotrophic lateral sclerosis (ALS). A growing body of evidence has demonstrated that misfolded SOD1 has prion-like properties such as transmissibility between cells and intracellular propagation of misfolding of natively folded SOD1. Recently, we found that SOD1 is misfolded in the cerebrospinal fluid of sporadic ALS patients, providing a route by which misfolded SOD1 spreads via the extracellular environment of the central nervous system.
View Article and Find Full Text PDFBackground: Neuroblastoma is one of the most commonly encountered malignant solid tumors in the pediatric age group. We examined the antitumor effects of five burchellin derivatives against human neuroblastoma cell lines.
Materials And Methods: We evaluated cytotoxicity by the MTT assay for four human neuroblastoma and two normal cell lines.
It has been recommended that active learning methods, such as team-based learning (TBL) and problem-based learning (PBL), be introduced into university classes by the Central Council for Education. As such, for the past 3 years, we have implemented TBL in a medical therapeutics course for 4-year students. Based upon our experience, TBL is characterized as follows: TBL needs fewer teachers than PBL to conduct a TBL module.
View Article and Find Full Text PDFCurr Pharm Des
April 2019
Lou Gehrig's disease, a synonym of amyotrophic lateral sclerosis, is an adult-onset lethal neurodegenerative disorder. Irrespective of extensive efforts to elucidate the pathogenesis of the disease and searches for therapies, no favorable pharmacotherapeutic strategies have yet to be proposed. In a popular rodent model of ALS, G93A SOD1 strain of mouse, intracellular copper conditions were geared toward copper accumulation inside cells, resulting in an acceleration of oxidative stress and apoptotic process.
View Article and Find Full Text PDFJapanese eel endothelial cells-infecting virus (JEECV) has spread in eel farms and caused serious economic loss. In this study, we examined the prevalence of JEECV infection in 100 wild Japanese eel (Anguilla japonica) elvers caught from Yamaguchi prefecture, Japan, using quantitative PCR and conventional PCR. Total genomic DNA was obtained from the cranial quarter of the body in 70 of 100 eels and from the gill in the remaining.
View Article and Find Full Text PDFJapanese eel endothelial cell-infecting virus (JEECV) causes viral endothelial cell necrosis of eel (VECNE), resulting in severe economic losses in eel aquaculture in Japan. Here, we report the complete genome sequences of two new JEECV strains isolated from farmed Japanese eels.
View Article and Find Full Text PDFA novel dsRNA virus was identified from the arboreal ant Camponotus yamaokai. The complete nucleotide sequence analysis of the virus revealed that the virus consisted of 5704 bp with two ORFs. ORF1 (3084 nt) encoded a putative capsid protein.
View Article and Find Full Text PDFMutations in SOD1 cause amyotrophic lateral sclerosis (ALS), an incurable motor neuron disease. The pathogenesis of the disease is poorly understood, but intracellular copper dyshomeostasis has been implicated as a key process in the disease. We recently observed that metallothioneins (MTs) are an excellent target for the modification of copper dyshomeostasis in a mouse model of ALS (SOD1(G93A)).
View Article and Find Full Text PDFOver 170 mutations in superoxide dismutase-1 (SOD1) cause familial amyotrophic lateral sclerosis (ALS), a lethal motor neuron disease. Although the molecular properties of SOD1 mutants differ considerably, we have recently shown that intracellular copper dyshomeostasis is a common pathogenic feature of different SOD1 mutants. Thus, the potentiation of endogenous copper regulation could be a therapeutic strategy.
View Article and Find Full Text PDFOver 170 mutations in superoxide dismutase-1 (SOD1) have been linked to amyotrophic lateral sclerosis (ALS). The properties of SOD1 mutants differ considerably including copper-binding abilities. Nevertheless, they cause the same disease phenotype, suggesting a common neurotoxic pathway.
View Article and Find Full Text PDFEconomic loss due to viral endothelial cell necrosis of eel (VECNE) of Anguilla japonica is a serious problem for the cultured Japanese eel market. However, the viral genome responsible for VECNE is unknown. We recently developed a rapid determination system for viral nucleic acid sequences (RDV) to determine viral genome sequences.
View Article and Find Full Text PDFDopamine agonists have neuroprotective properties in addition to their original pharmacologic function. We examined the effects of pergolide mesilate (PM) on the levels of metallothionein mRNA expression and lipid peroxidation in the corpus striata of 1-methyl 4-phenyl 1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinsonian mice. Mice were administered normal saline (vehicle as a control), PM, or MPTP.
View Article and Find Full Text PDFMutations in copper/zinc superoxide dismutase (SOD1) are responsible for 20% of familial amyotrophic lateral sclerosis through a gain-of-toxic function. We have recently shown that ammonium tetrathiomolybdate, an intracellular copper-chelating reagent, has an excellent therapeutic benefit in a mouse model for amyotrophic lateral sclerosis. This finding suggests that mutant SOD1 might disrupt intracellular copper homeostasis.
View Article and Find Full Text PDFBackground: Lack of receptor tyrosine kinase (TrkA), a high-affinity nerve growth factor (NGF) receptor, is closely associated with the malignant progression of neuroblastoma (NB) and its prognosis. Vitamin K3 (VK3) analogs inhibit the activity of protein tyrosine phosphatases (PTPases), which causes hydrolysis of the phosphate groups bound to the tyrosine residues on tyrosine kinase, resulting in sustained tyrosine phosphorylation.
Methods: In order to reverse this abnormal NGF/TrkA signal transduction in NB cells, we synthesized new VK3 analogs and examined their activity against NB cells.
Mutations in copper/zinc superoxide dismutase (SOD1) cause a form of familial amyotrophic lateral sclerosis (ALS). The pathogenesis of familial ALS may be associated with aberrant copper chemistry through a cysteine residue in mutant SOD1. Ammonium tetrathiomolybdate (TTM) is a copper-chelating drug that is capable of removing a copper ion from copper-thiolate clusters, such as SOD1.
View Article and Find Full Text PDFSeveral studies have indicated that lipid peroxidation often occurs in response to oxidative stress, and that many aldehydic products including 4-hydroxy-2-nonenal (HNE) are formed when lipid hydroperoxides break down. In order to clarify the mechanism of oxidative stress-induced neuronal death in the nervous system, we investigated H(2)O(2)- and HNE-induced cell death pathways in HT22 cells, a mouse hippocampal cell line, under the same experimental conditions. Treatment with H(2)O(2) and HNE decreased the viability of these cells in a time- and concentration-dependent manner.
View Article and Find Full Text PDFThe induction of metallothionein (MT) isoform synthesis was investigated in mouse cerebral cortex 18 h after oral ethanol administration. The expression of MT-I isoform mRNA increased in a dose-dependent manner after ethanol loading at doses between 2 g/kg (ethanol/body weight) and 8 g/kg. Lipid peroxide formation, measured as the amount of malondialdehyde- reactive substances, remained at the control level after all of the administered ethanol doses.
View Article and Find Full Text PDFMutations in copper/zinc superoxide dismutase (SOD1) have been implicated in the pathogenesis of familial amyotrophic lateral sclerosis (ALS). Mutant SOD1 protein likely gains a novel cytotoxic property, leading to the death of motor neurons. We therefore investigated whether caspase-mediated apoptosis is associated with novel cytotoxic properties in a rodent model for familial ALS (G93A SOD1 transgenic mice).
View Article and Find Full Text PDFMetallothionein (MT) mRNA expression was investigated in a rodent model (G93A SOD1 transgenic mouse) for a lethal motor neuron disease, amyotrophic lateral sclerosis (ALS). In 8-wk-old mice that did not yet exhibit motor paralysis, MT-I mRNA expression was already significantly upregulated in the region of the spinal cord responsible for motor paralysis. The expression of another isoform, MT-III, was not changed.
View Article and Find Full Text PDFIt has been hypothesized that copper-mediated oxidative stress contributes to the pathogenesis of familial amyotrophic lateral sclerosis (ALS), a fatal motor neuron disease in humans. To verify this hypothesis, we examined the copper and zinc concentrations and the amounts of lipid peroxides, together with that of the expression of metallothionein (MT) isoforms in a mouse model [superoxide dismutase1 transgenic (SOD1 Tg) mouse] of ALS. The expression of MT-I and MT-II (MT-I/II) isoforms were measured together with Western blotting, copper level, and lipid peroxides amounts increased in an age-dependent manner in the spinal cord, the region responsible for motor paralysis.
View Article and Find Full Text PDFWe report a rare case of acute autonomic, sensory and motor neuropathy (AASMN). The patient, a 26-year-old woman, developed fever and common cold around January 20, 2001 and was admitted because of abdominal pain due to ileus on January 30. After admission, the patient complained of muscle weakness and numbness in the extremities, difficulty in seeing with the right eye, and dysuria.
View Article and Find Full Text PDFWe report a case of anaphylactoid shock occurring immediately after the initiation of second intravenous administration of high-dose immunoglobulin (IVIg) in a patient with Crow-Fukase syndrome. The patient was a 57-year-old woman, who was admitted to our hospital because of numbness and muscle weakness in the four extremities, difficulty in walking, and foot edema. On admission, her skin was dry and rough, and also showing scattered pigmentation, small hemangiomas, and hypertrichosis in both legs.
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