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71.
The Awajishima Monkey Center (AMC) free-ranging, provisioned population of Japanese macaques has included individuals with congenital limb malformations (CLMs) for at least 40 years. Including new data from this study, 16.1% of AMC infants from 1969 to 2007 (185 of 1,150) were born with CLMs. However, relatively little is known about the demographics of CLMs in the population, particularly the relationships among occurrence and severity of CLMs and age-sex demographics after infancy. In 2004, we conducted a census at AMC. Of the 199 monkeys censused, 34 individuals (17.1%) had CLMs. To estimate the severity of CLMs, we created an index that ranks individuals on a scale of 0 to 1 based on affected and absent limbs and digits. The severity of CLMs varied greatly (index range = 0.01-0.79, mean = 0.29), with similar variation in severity in each age-sex class (Student t-test, P > 0.05).  相似文献   
72.
Two Tetrahymena kinesin-like proteins (klps) of the kinesin II subfamily, Kin1 and Kin2, were first identified by Brown et al. [1999: Mol Biol Cell 10: 3081-3096] and shown to be involved in ciliary morphogenesis probably as molecular motors in intraciliary transport (ICT). Using Tetrahymena genomic DNA as a template, we cloned Kin5, another kinesin II subfamily member. Kin5 is upregulated upon deciliation, suggesting that Kin5 is a ciliary protein. Kin5 is most closely related to Osm3, a Caenorhabditis elegans kinesin II; Osm3 and Kin5 have a 56% identity, which rises to 60.4% in the motor domain and a 45% identity in a 60 amino acid region of the C-terminal FERM (4.1, Ezrin, Radixin, Moesin) domain, not present in Kin1 or Kin2, which we hypothesize to be a critical domain either for dimerization or for cargo recognition in ICT. An antibody to a peptide sequence from the tail region of Kin5 localizes in a punctate pattern along the ciliary axoneme, colocalizing with an antibody to the raft protein IFT139. These findings suggest that Kin5 is an ICT motor like Osm3. Osm3 orthologs apparently transport membrane proteins and Kin5 may be the homodimeric kinesin II that performs this function in Tetrahymena cilia.  相似文献   
73.
Cassava is a starch-containing root crop that is widely used as a raw material in a variety of industrial applications, most recently in the production of fuel ethanol. In the present study, ethanol production from raw (uncooked) cassava flour by simultaneous saccharification and fermentation (SSF) using a preparation consisting of multiple enzyme activities from Aspergillus kawachii FS005 was investigated. The multi-activity preparation was obtained from a novel submerged fermentation broth of A. kawachii FS005 grown on unmilled crude barley as a carbon source. The preparation was found to consist of glucoamylase, acid-stable α-amylase, acid carboxypeptidase, acid protease, cellulase and xylanase activities, and exhibited glucose and free amino nitrogen (FAN) production rates of 37.7 and 118.7 mg/l/h, respectively, during A. kawachii FS005-mediated saccharification of uncooked raw cassava flour. Ethanol production from 18.2% (w/v) dry uncooked solids of raw cassava flour by SSF with the multi-activity enzyme preparation yielded 9.0% (v/v) of ethanol and 92.3% fermentation efficiency. A feasibility study for ethanol production by SSF with a two-step mash using raw cassava flour and the multi-activity enzyme preparation manufactured on-site was verified on a pilot plant scale. The enzyme preparation obtained from the A. kawachii FS005 culture broth exhibited glucose and FAN production rates of 41.1 and 135.5 mg/l/h, respectively. SSF performed in a mash volume of about 1,612 l containing 20.6% (w/v) dry raw cassava solids and 106 l of on-site manufactured A. kawachii FS005 culture broth yielded 10.3% (v/v) ethanol and a fermentation efficiency of 92.7%.  相似文献   
74.
Mitochondria and plastids multiply by division in eukaryotic cells. Recently, the eukaryotic homolog of the bacterial cell division protein FtsZ was identified and shown to play an important role in the organelle division process inside the inner membrane. To explore the evolution of FtsZ proteins, and to accumulate data on the protein import system in mitochondria and plastids of the red algal lineage, one mitochondrial and three plastid ftsZ genes were isolated from the diatom Chaetoceros neogracile, whose plastids were acquired by secondary endosymbiotic uptake of a red alga. Protein import into organelles depends on the N‐terminal organelle targeting sequences. N‐terminal bipartite presequences consisting of an endoplasmic reticulum signal peptide and a plastid transit peptide are required for protein import into diatom plastids. To characterize the organelle targeting peptides of C. neogracile, we observed the localization of each green fluorescent protein‐tagged predicted organelle targeting peptide in cultured tobacco cells and diatom cells. Our data suggested that each targeting sequences functioned both in tobacco cultured cells and diatom cells.  相似文献   
75.
Advanced diabetic nephropathy is characterized by abnormal synthesis of extracellular matrix (ECM) proteins, such as collagen I (COL I). The present experiments were designed to test the hypothesis that the presence of abnormal ECM proteins may be responsible for increased generation of reactive oxygen species (ROS) that are thought to have an important role in the pathogenesis of diabetic nephropathy. SV40 MES 13 murine mesangial cells were plated on COL I or collagen IV (COL IV) for 3 h at 5.5 or 25 mM D-glucose concentration. Increased intracellular ROS generation and reduced intracellular nitric oxide (NO) production was measured in cells attached to COL I compared with cells attached to COL IV. Treatment with N(omega)-nitro-L-arginine methyl ester hydrochloride (L-NAME), an inhibitor of NO synthase, reduced this difference in ROS generation between cells attached to either COL I or IV. The results using antibodies against integrins also indicated that an alpha(2) integrin-mediated pathway was involved in the different response in ROS generation caused by ECM proteins. These results suggest that contact between altered ECM proteins that are present in advanced diabetic nephropathy and mesangial cells has the potential to increase intracellular oxidative stress, leading to progressive glomerular damage.  相似文献   
76.
To investigate the biochemical and enzymatic properties of two aldehyde oxidase (AO) isoforms of Arabidopsis thaliana, we expressed AAO1 and AAO2 cDNAs in a heterologous yeast (Pichia pastoris) system and successfully obtained the proteins in active forms. The expressed AAO1 and AAO2 proteins gave activity bands with the same mobilities on native gel electrophoresis and exhibited the same substrate preferences on zymograms with 8 aldehydes as those of AOalpha and AOgamma in Arabidopsis seedlings, respectively. Furthermore, anti-AAO1 and anti-AAO2 antibodies, which specifically recognize the seedling AOalpha and AOgamma, respectively, reacted with the AAO1 and AAO2 proteins produced in P. pastoris, respectively. These results indicate that these AO proteins are accurately produced in the yeast system, as in Arabidopsis seedlings. Using AO preparations from P. pastoris, the enzymatic properties of Arabidopsis AOalpha and AOgamma were investigated. AOalpha showed a relatively wide substrate specificity for 7 aldehydes tested, with high affinity to benzaldehyde and indole-3-aldehyde, while AOgamma could most efficiently oxidize naphthaldehyde. AOalpha was strongly inhibited by iodoacetate and KCN, while AOgamma was inhibited not only by iodoacetate and KCN but also by 2-mercaptethanol, dithiothreitol, menadion, and estradiol. AOalpha and AOgamma showed the highest activity at around 65 and 50 degrees C, respectively, and exhibited pH dependence around pH 8.0. These results indicate that the two AO isoforms in Arabidopsis seedlings have different enzymatic properties and may have different physiological roles in vivo.  相似文献   
77.
Cholestasis, an impairment of bile outflux, frequently occurs in liver diseases. In this process, an overaccumulation of bile acids causes hepatocyte necrosis and apoptosis, leading to advanced hepatitis. Hepatocyte growth factor (HGF) is mitogenic toward hepatocytes, but it is still unclear whether HGF has physiological and therapeutic functions during the progression of cholestasis. Using anti-HGF IgG or recombinant HGF in mice that had undergone bile duct ligation (BDL), we investigated the involvement of HGF in cholestasis-induced hepatitis. After the BDL surgery, HGF and c-Met mRNA levels transiently increased in livers during the progression of cholestatic hepatitis. When c-Met tyrosine phosphorylation was blocked in the livers of BDL-treated mice by anti-HGF IgG, hepatic dysfunction became evident, associated with the acceleration of hepatocyte necrosis and apoptosis. Inversely, administration of recombinant HGF into the mice led to the prevention of cholestasis-induced inflammation: HGF suppressed the hepatic expression of intracellular adhesion molecule-1 and neutrophil infiltration in BDL-treated mice. As a result, parenchymal necrosis was suppressed in the HGF-injected BDL mice. In addition, HGF supplement therapy reduced the number of apoptotic hepatocytes in cholestatic mice, associated with the early induction of Bcl-xL. The administration of HGF enhanced hepatic repair, via accelerating G1/S progression in hepatocytes. Our study showed that 1) upregulation of HGF production is required for protective mechanisms against cholestatic hepatitis and 2) enhancement of the intrinsic defense system by adding HGF may be a reasonable strategy to attenuate hepatic inflammation, necrosis, and apoptosis under bile-congestive conditions.  相似文献   
78.
Mechanisms and significance of bifunctional NK4 in cancer treatment   总被引:4,自引:0,他引:4  
Based on the background that hepatocyte growth factor (HGF) and c-Met/HGF receptor tyrosine kinase play a definite role in tumor invasion and metastasis, NK4, four-kringles containing intramolecular fragment of HGF, was isolated as a competitive antagonist for the HGF-c-Met system. Independent of its HGF-antagonist action, NK4 inhibited angiogenesis induced by vascular endothelial cell growth factor and basic fibroblast growth factor, as well as HGF, indicating that NK4 is a bifunctional molecule that acts as an HGF-antagonist and angiogenesis inhibitor. Interestingly, kringle domains in distinct types of proteins, e.g., plasminogen, prothrombin, plasminogen activators, apolipoprotein(a), and HGF, share angioinhibitory actions. In experimental models of distinct types of cancers, NK4 protein administration or NK4 gene therapy inhibited tumor invasion, metastasis, and angiogenesis-dependent tumor growth. Cancer treatment with NK4 may prove to suppress malignant tumors to be 'static' in both tumor growth and spreading, as based on biological characteristics of malignant tumors.  相似文献   
79.
Angelica keiskei (Ashitaba in Japanese), a traditional herb in Japan, contains abundant prenylated chalcones. It has been reported that the chalcones from A. keiskei showed such bioactivities as anti-bacterial, anti-cancer and anti-diabetic effects. Xanthoangelol, 4-hydroxyderricin and six new chalcones were isolated in this study from an ethanol extract of A. keiskei by octadecyl silyl (ODS) and silica gel chromatography, and identified by 1D- and 2D-nuclear magnetic resonance (NMR) and high-resolution mass spectrometric analyses. The chalcones from A. keiskei markedly increased the expression of the adiponectin gene and the production of adiponectin in 3T3-L1 adipocytes. These results suggest that the chalcones from A. keiskei might be useful for preventing the metabolic syndrome.  相似文献   
80.
κ-Casein and αs1-κ-casein complex with a weight ratio of unity were dissolved in 50mm cacodylate-HCl-70 mm KC1 buffer containing 0.02% of sodium azide (pH 7.1), and their size and shape in the absence and/or presence of calcium ions were observed with the electron microscope. In the absence of calcium ions, both κ-casein and αs1-κ-casein complex were spherical particles. However, the mean length of αs1-κ-casein complex (12 nm) was smaller than that of κ-casein (17 nm), which suggested that complex formation led to dissociation of the κ-casein polymer. The addition of calcium ions to the complex led to the formation of bent chains, though micelle-like aggregates were not observed even at 20 nm calcium. Comparison of the frequency distributions of αs1-κ-casein complex at 0, 5, 10, 15 and 20 mm of calcium with the calculated probability distributions suggested that most αs1-κ-casein complexes had two binding sites above 10 mm of calcium, which seemed to be essential for the stability of casein micelle.  相似文献   
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