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91.
Objective: This study used a precise weighing method to assess whether tooth loss was related to nutrient intake in elderly Japanese subjects. Material and methods: Fifty‐seven subjects aged 74 years were randomly selected from a longitudinal interdisciplinary study of ageing. Complete 3‐day food intake data were obtained by a precise weighing method. The dietary intakes of energy and nutrients were calculated based on the Standard Tables of Food Composition in Japan (5th ed.). A clinical evaluation of the number of teeth present was carried out. Multiple regression standardised coefficients for each nutrient was estimated based on a continuous scale adjusted for gender, smoking habits, and educational level. After dividing the subjects into two groups according to the number of teeth present (0–19, 20+), the difference in the intake of nutrients and the amount of food consumed per day was evaluated. Results: The number of teeth present had a significant relationship with the intake of several nutrients. In particular, total protein, animal protein, sodium, vitamin D, vitamin B1, vitamin B6, niacin, and pantothenic acid were significantly associated with the number of teeth present and with the two groups (0–19, 20+). The intake of vegetables and fish, shellfish, and their products was significantly lower among subjects with fewer teeth. Conclusion: This study suggests that there was a significant relationship between nutrient intake, such as minerals and vitamins from food, and tooth loss.  相似文献   
92.
The main isozyme patterns of desialylated blood plasma or serum -l-fucosidase (FUCA) were found to be almost identical to those of semen, urine, placental extracts, and leukocyte lysates, when detected by polyacrylamide gel isoelectric focusing, and activity staining using the fluorogenic substrate 4-methylumbelliferyl--l-fucopyranoside. Three phenotypes (1, 2-1, and 2) determined from plasma samples were identical to the phenotypes from urine and leukocyte lysates from the same individuals. A population study of plasma samples collected from 485 Japanese individuals indicated that the frequencies of the FUCA11 * and FUCA12 * alleles were 0.7505 and 0.2495, respectively. The mean plasma enzyme activities (+SD) of the three phenotypes were 318.8 ± 116.7 nmol/ml per h for type 1, 268.0 ± 108.3 nmol/ml per h for type 2-1, and 233.2 ± 84.4 nmol/ml per h for type 2. The mean activities of types 1 and 2 suggest that, on average, the FUCA11 * gene product in plasma has about 1.4 times the activity of FUCA12 *.  相似文献   
93.
94.
Autophagy is a bulk protein degradation system for the entire organelles and cytoplasmic proteins. Previously, we have shown the liver dysfunction by autophagy deficiency. To examine the pathological effect of autophagy deficiency, we examined protein composition and their levels in autophagy-deficient liver by the proteomic analysis. While impaired autophagy led to an increase in total protein mass, the protein composition was largely unchanged, consistent with non-selective proteins/organelles degradation of autophagy. However, a series of oxidative stress-inducible proteins, including glutathione S-transferase families, protein disulfide isomerase and glucose-regulated proteins were specifically increased in autophagy-deficient liver, probably due to enhanced gene expression, which is induced by accumulation of Nrf2 in the nuclei of mutant hepatocytes. Our results suggest that autophagy deficiency causes oxidative stress, and such stress might be the main cause of liver injury in autophagy-deficient liver.  相似文献   
95.
The location of chromosomal DNA replication forks was identified in synchronously replicating E. coli cultures by pulse labeling DNA at specific times with 14C-thymidine and following incorporation of radionucleotide into genomic Not I restriction fragments. This technique could be used to characterize chromosomal DNA replication, to characterize mutations which affect this process, to identify the location of DNA replication origins and termini as well as aid in the construction of macrorestriction maps. Here, we further characterize the DNA replication mutations divE and dnaK and preliminary characterize the genomic organization of E. coli isolate 15.  相似文献   
96.
Demonstration of a dawn phenomenon in normal adolescents   总被引:1,自引:0,他引:1  
To ascertain whether the dawn phenomenon occurs in normal adolescents and, if so, to determine its mechanism, we measured nocturnal plasma glucose, insulin, glucagon, growth hormone, cortisol, and adrenocorticotropic hormone (ACTH) levels between 01.00 and 08.00 h in 10 healthy adolescents. The prehepatic insulin secretion rate was calculated based on C peptide levels. The metabolic clearance rate of insulin (MCRI) was calculated as the ratio of mean insulin secretion rate to mean insulin concentration. There was no change in plasma glucose, insulin, and glucagon between 01.00-04.00 and 05.00-08.00 h (paired t test). The MCRI was higher at 05.00-08.00 h compared to 01.00-04.00 h (9.30 +/- 1.50 vs. 4.87 +/- 1.11 ml.kg-1.min-1; p = 0.008). The prehepatic insulin secretion increased at 05.00-08.00 h relative to 01.00-04.00 h (1.1 +/- 0.2 vs. 0.6 +/- 0.1 pmol.kg-1.min-1; p = 0.013). Similarly, cortisol and ACTH levels were higher at 05.00-08.00 versus 01.00-04.00 h (323 +/- 33 vs. 102 +/- 22 nmol/l, p less than 0.001; 3.6 +/- 0.5 vs. 1.8 +/- 0.4 pmol/l, p = 0.006, respectively). Growth hormone was higher at 01.00-04.00 versus 05.00-08.00 h (7.6 +/- 1.2 and 3.0 +/- 0.9 microgram/l; p = 0.019). ACTH correlated with MCRI (r = 0.66; p = 0.002) and prehepatic insulin secretion (r = 0.75; p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
97.
98.
TLRs detect several classes of virus-associated molecules, such as ssRNA, CpG-DNA and dsRNA, and transduce signals leading to the production of IFN. Recently discovered cytoplasmic RNA helicases, RIG-I and MDA5, selectively sense viral RNA species. Gene disruption studies revealed the critical but non-redundant function of RIG-I and MDA5 in host antiviral responses.  相似文献   
99.
100.
Phosphorylation of endogenous inhibitor proteins for type-1 Ser/Thr phosphatase (PP1) provides a mechanism for reciprocal coordination of kinase and phosphatase activities. A myosin phosphatase inhibitor protein CPI-17 is phosphorylated at Thr38 through G-protein-mediated signals, resulting in a >1000-fold increase in inhibitory potency. We show here the solution NMR structure of phospho-T38-CPI-17 with rmsd of 0.36 +/- 0.06 A for the backbone secondary structure, which reveals how phosphorylation triggers a conformational change and exposes an inhibitory surface. This active conformation is stabilized by the formation of a hydrophobic core of intercalated side chains, which is not formed in a phospho-mimetic D38 form of CPI-17. Thus, the profound increase in potency of CPI-17 arises from phosphorylation, conformational change, and hydrophobic stabilization of a rigid structure that poses the phosphorylated residue on the protein surface and restricts its hydrolysis by myosin phosphatase. Our results provide structural insights into transduction of kinase signals by PP1 inhibitor proteins.  相似文献   
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