Microscopy, Electron, Transmission

Publication Title: 
Neurobiology of Disease

An increasing body of evidence indicates a role for oligomers of the amyloid-? peptide (A?) in the neurotoxicity of this peptide and the pathology of Alzheimer's disease (AD). Several neurotoxic oligomeric forms of A? have been noted ranging from the larger Amyloid ?-Derived Diffusible Ligands (ADDLs) to smaller trimers and dimers of A?. More recently a dodecameric form of A? with a 56 kDa molecular weight, denoted A?*56, was shown to cause memory impairment in AD model mice.

Author(s): 
Scherzer-Attali, R.
Farfara, D.
Cooper, I.
Levin, A.
Ben-Romano, T.
Trudler, D.
Vientrov, M.
Shaltiel-Karyo, R.
Shalev, D. E.
Segev-Amzaleg, N.
Gazit, E.
Segal, D.
Frenkel, D.
Publication Title: 
Proceedings of the National Academy of Sciences of the United States of America

Dietary interventions are effective ways to extend or shorten lifespan. By examining midlife hepatic gene expressions in mice under different dietary conditions, which resulted in different lifespans and aging-related phenotypes, we were able to identify genes and pathways that modulate the aging process. We found that pathways transcriptionally correlated with diet-modulated lifespan and physiological changes were enriched for lifespan-modifying genes.

Author(s): 
Zhou, Bing
Yang, Liu
Li, Shoufeng
Huang, Jialiang
Chen, Haiyang
Hou, Lei
Wang, Jinbo
Green, Christopher D.
Yan, Zhen
Huang, Xun
Kaeberlein, Matt
Zhu, Li
Xiao, Huasheng
Liu, Yong
Han, Jing-Dong J.
Publication Title: 
The Journals of Gerontology. Series A, Biological Sciences and Medical Sciences

We analyzed ultrastructural changes and markers of fission/fusion in hepatocyte mitochondria from mice submitted to 40% calorie restriction (CR) for 6 months versus ad-libitum-fed controls. To study the effects of dietary fat under CR, animals were separated into three CR groups with soybean oil (also in controls), fish oil, and lard. CR induced differential changes in hepatocyte and mitochondrial size, in the volume fraction occupied by mitochondria, and in the number of mitochondria per hepatocyte.

Author(s): 
Khraiwesh, Husam
LÛpez-DomÌnguez, JosÈ A.
LÛpez-Lluch, Guillermo
Navas, Pl·cido
de Cabo, Rafael
Ramsey, Jon J.
Villalba, JosÈ M.
Gonz·lez-Reyes, JosÈ A.
Publication Title: 
The Journal of Biological Chemistry

At the core of Saccharomyces cerevisiae telomeres is an array of tandem telomeric DNA repeats bound site-specifically by multiple Rap1 molecules. There, Rap1 orchestrates the binding of additional telomere-associated proteins and negatively regulates both telomere fusion and length homeostasis. Using electron microscopy, viscosity, and light scattering measurements, we show that purified Rap1 is a monomer in solution that adopts a ringlike or C shape with a central cavity.

Author(s): 
Williams, Tanya L.
Levy, Daniel L.
Maki-Yonekura, Saori
Yonekura, Koji
Blackburn, Elizabeth H.
Publication Title: 
International Journal of Nanomedicine

We developed a novel method to prepare nanocapsules. A solute often crystallizes when its solubility alters from one solvent to another, and its firstborn crystals are used as templates to prepare nanocapsules for the first time, which is called firstborn microcrystallization method. By using this method, the maximum diameter of the nanocapsules including artesunate is about 76 nm, and wrapping state is well.

Author(s): 
Xiao, Xin-Cai
Hong, Zong-Guo
Publication Title: 
Ultrastructural Pathology

Ultrastructural changes to P. falciparum-infected red blood cells were examined in vitro after treatment with antimalarial drugs. Artesunate had the most rapid parasitocidal effect. All three drugs caused structural changes within the parasite, including dilatation of the parasitophorus vacuole membrane, depletion of ribosomes, mitochondrial swelling, and decreased formation of hemozoin crystals. The structure of surface knobs and Maurer's clefts were similar to controls but reduced in number. Only depletion of free ribosomes correlated with antimalarial drug exposure.

Author(s): 
Sachanonta, Navakanit
Chotivanich, Kesinee
Chaisri, Urai
Turner, Gareth D. H.
Ferguson, David J. P.
Day, Nicholas P. J.
Pongponratn, Emsri
Publication Title: 
PloS One

The objective of our study was to profile and compare the systematic changes between orally administered artesunate and intramuscularly injected artemether at a low dose over a 3-month period (92 consecutive days) in dogs. Intramuscular administration of 6 mg kg-1 artemether induced a decreased red blood cell (RBC) count (anemia), concurrent extramedullary hematopoiesis in the spleen and inhibition of erythropoiesis in the bone marrow.

Author(s): 
Yin, Ji-ye
Wang, He-mei
Wang, Quan-jun
Dong, Yan-sheng
Han, Gang
Guan, Yong-biao
Zhao, Ke-yong
Qu, Wen-sheng
Yuan, Ye
Gao, Xiao-xin
Jing, Shu-fang
Ding, Ri-gao
Publication Title: 
Neurotoxicology

Bacopa monniera is a nerve tonic used extensively in traditional Indian medicinal system "Ayurveda". Reports regarding its various antioxidative, adaptogenic and memory enhancing roles have already appeared in the last few decades. In the present study, aluminium chloride (AlCl(3)) was used to generate neurotoxicity. We have investigated the neuroprotective effect of Bacopa extract against aluminium-induced changes in peroxidative products, such as thio-barbituric acid-reactive substance (TBA-RS) and protein carbonyl contents and superoxide dismutase (SOD) activity.

Author(s): 
Jyoti, Amar
Sharma, Deepak
Publication Title: 
Phytotherapy research: PTR

The Ayurvedic system of medicine recommends Bacopa monniera (BM) in the treatment of tumors. The present study aims to determine the mode of cell death induced by the ethanolic extract of BM in mouse S-180 cells. BM-treated S-180 cells were assessed for cell viability in a dose- and time-dependent manner using dye exclusion studies. Morphological changes in the BM-treated and untreated cells were studied by transmission electron microscopy (TEM). Glutathione (GSH) levels were quantified and the percentage of apoptotic cells was determined using Annexin V-FITC assay.

Author(s): 
Rohini, G.
Devi, C. S. Shyamala
Publication Title: 
Phytotherapy research: PTR

The ability of an aqueous extract of W. somnifera L. Dunal (Family: Solanaceae) roots to inhibit fibril formation by the amyloid-β peptide in vitro was investigated. W. somnifera is used extensively in traditional Ayurvedic medicine as a nerve tonic with reputed memory enhancing properties. Inhibition of fibrillogenesis measured by transmission electron microscopy and ThT fluorescence assay showed that an aqueous extract of W. somnifera strongly inhibited Aβ fibril formation in a concentration-dependent manner, when compared with control samples.

Author(s): 
Kumar, Suresh
Harris, Robin J.
Seal, Christopher J.
Okello, Edward J.

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