256 research outputs found
Dissociation of Alzheimer's morphological pathology from cognitive impairment
We observed the Alzheimer's morphological pathology, amyloid production induces Alzheimer's cognitive impairment, was dissociated from the cognitive impairment. The earlier Alzheimer's pathological changes can be induced in normal C57BL mice, by B6 deficient feeding 4 months with no amyloid, and this cognitive and memory impairments were completely inhibited by anti-homocysteic acid antibody. According to Koch's postulate, if a pathogen of Alzheimer's disease is administrated to the normal animal, we would observe the Alzheimer's cognitive impairment in the normal animal. We actually have observed this cognitive impairment in normal C57BL male mice with no amyloid. From our observations, it is suggested the dissociation of Alzheimer's morphological pathology may be possible from the cognitive impairment
Pathogenesis of AD is similar to that of uremic encephalopathy of Homocysteic acid.
Homocysteic acid (HA) has been established as a pathogen in Alzheimer's disease (AD) in 3xTg-AD model mice. However, it is not established whether HA is involved in the AD pathogenesis in humans. We investigated the relationship between urinary HA levels and Mini-Mental State Examination (MMSE) scores in patients with AD (n = 110, normal =22, AD=88) and found a positive, statistically significant relationship between the two variables (r = 0.39, p =0.00003, n = 110). This relationship was stronger in females. (r = 0.47, p = 0.00008, n = 65 in females; r = 0.39, p = 0.02, n =45 in males). The difference in the urinary HA level between normal and AD females was statistically significant (normal:18.4 + 10.6vsAD: 9.1 + 7.2 mM,p<0.01), but this difference in males was not statistically significant. (normal:12.7 + 6 vs AD8.8 + 7.8). Smoking, hypertension, and diabetes mellitus decreased urinary HA excretion. On the basis of these results, we showed that HA is usually excreted into urine in humans and did not affect brain function in normal individuals. However, when urinary HA excretion was decreased, HA was shown to damage brain function, particularly cognitive ability. To confirm our hypothesis, that is, when urinary HA is suppressed to be excreted into urine, the blood HA level will increase, we examined the relationship between the urinary HA level and blood HA level in 19 patients. The result was shown that the negative statistically significant relationship between them was observed (r=-0.6, p=0.007, n=19). From this result, the uremic encephalopathy of HA toxicity was confirmed. However there remains the question of how the blood HA affected the brain's cognitive function. The direct effect of green tea leaves ingestion on HA level and MMSE score were also observed. Ingested green tea leaves decreased HA level in blood and concomitantly increased MMSE score, suggesting that blood HA could affect cognitive function. But How? Some papers showed that exogenous NMDA including HA disrupted the blood brain barrier and entered into the brain and affected the cognitive function to decrease MMSE score. These results indicate that human AD pathogenesis is influenced by HA, and that HA is a human pathogen in AD, indicating that the pathogenesis of AD is similar to that of uremic encephalopathy. Also, urinary HA can be used as a biomarker for Alzheimer's disease
Treatment of Alzheimer's Disease with Anti-Homocysteic acid Antibody
Homocysteic acid (HA) may play an important role in Alzhiemer disease (AD) as we previously reported that HA induced accumulation of intraneuronal A[beta]42. In this study, we first analyzed HA levels in a mouse model of AD. 4-month old pre-pathologic 3xTg-AD mice exhibited higher levels of HA in the hippocampus as compared to age-matched nontransgenic, suggesting that HA accumulation may precede both A[beta] and tau pathologies. To further determine the pathogenic role of HA in AD, we treated young 3xTg-AD mice with vitamin B6-deficient food for 3 weeks to induce the production of HA in the brain. Concominantly, mice received either saline or anti-HA antibody intraventricularly using a guide cannula every 3 days. Mice received anti-HA antibody significantly rescued cognitive impairment induced by vitamin B6 deficiency. Pathologically, 3-week treatment with vitamin B-6 deficient food resulted in strong neurodegeneration in the hippocampal CA1 zone and decreased hippocampal volume. In contrast, anti-HA antibody treatment attenuated these pathological changes. Taken together, we conclude that increased brain HA triggers memory impairment whose condition was deteriorated by amyloid and subsequent neurodegeneration and reduction of neurogenesis. Our results indicate a pathogenic role of HA in AD
Treatment of Alzheimer's Disease with Anti-Homocysteic acid Antibody
Homocysteic acid (HA) may play an important role in Alzhiemer disease (AD) as we previously reported that HA induced accumulation of intraneuronal A[beta]42. In this study, we first analyzed HA levels in a mouse model of AD. 4-month old pre-pathologic 3xTg-AD mice exhibited higher levels of HA in the hippocampus as compared to age-matched nontransgenic, suggesting that HA accumulation may precede both A[beta] and tau pathologies. To further determine the pathogenic role of HA in AD, we treated young 3xTg-AD mice with vitamin B6-deficient food for 3 weeks to induce the production of HA in the brain. Concominantly, mice received either saline or anti-HA antibody intraventricularly using a guide cannula every 3 days. Mice received anti-HA antibody significantly rescued cognitive impairment induced by vitamin B6 deficiency. Pathologically, 3-week treatment with vitamin B-6 deficient food resulted in strong neurodegeneration in the hippocampal CA1 zone and decreased hippocampal volume. In contrast, anti-HA antibody treatment attenuated these pathological changes. Taken together, we conclude that increased brain HA triggers memory impairment whose condition was deteriorated by amyloid and subsequent neurodegeneration and reduction of neurogenesis. Our results indicate a pathogenic role of HA in AD
B6 deficient feeding or homocysteic acid induces the earlier Alzheimer's pathological change in normal C57BL male mice
It is the first report that the earlier Alzheimer's pathological changes can be induced in normal C57BL mice, by B6 deficient feeding for 3 month, and this pathological changes were completely inhibited by anti-homocysteic acid antibody. According to Koch's postulate, if a pathogen of Alzheimer's disease is administrated to the normal animal, we would observe the Alzheimer's pathology in the normal animal. We actually have observed this pathology in normal C57BL male mice
Treatment of Alzheimer's Disease with Anti-Homocysteic Acid Antibody in 3xTg-AD Male Mice
Alzheimer's disease (AD) is an age-associated progressive neurodegenerative disorder with dementia, the exact pathogenic mechanisms of which remain unknown. We previously reported that homocysteic acid (HA) may be one of the pathological biomarkers in the brain with AD and that the increased levels of HA may induce the accumulation of intraneuronal amyloid-beta (Aβ) peptides. In this study, we further investigated the pathological role of HA in a mouse model of AD. Four-month-old prepathological 3xTg-AD mice exhibited higher levels of HA in the hippocampus than did age-matched nontransgenic mice, suggesting that HA accumulation may precede both Aβ and tau pathologies. We then fed 3-month-old 3xTg-AD mice with vitamin B6-deficient food for 3 weeks to increase the HA levels in the brain. Concomitantly, mice received either saline or anti-HA antibody intraventricularly via a guide cannula every 3 days during the course of the B6-deficient diet. We found that mice that received anti-HA antibody significantly resisted cognitive impairment induced by vitamin B6 deficiency and that AD-related pathological changes in their brains was attenuated compared with the saline-injected control group. A similar neuroprotective effect was observed in 12-month-old 3xTg-AD mice that received anti-HA antibody injections while receiving the regular diet. We conclude that increased brain HA triggers memory impairment and that this condition deteriorates with amyloid and leads to subsequent neurodegeneration in mouse models of AD
Formation of x-ray Newton’s rings from nano-scale spallation shells of metals in laser ablation
The initial stages of the femtosecond (fs) laser ablation process of gold, platinum, and tungsten were observed by single-shot soft x-ray imaging technique. The formation and evolution of soft x-ray Newton’s rings (NRs) were found for the first time. The soft x-ray NRs are caused by the interference between the bulk ablated surface and nanometer-scale thin spallation layer; they originate from the metal surface at pump energy fluence of around 1 J/cm2 and work as a flying soft x-ray beam splitter
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