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21.
The syntheses of novel C-nucleoside phosphonic acids as potential antiviral agents are described. The sugar moiety that served as the nucleoside skeleton was produced starting from commercially available 1,3-dihydroxy cyclopentane. The key C-C bond formation from sugar to base precursor was performed using the Knoevenagel-type condensation. The synthesized compounds exhibited anti-HIV activity and cytotoxicity. Also, the synthesized compounds were screened in vitro for tumor growth inhibitory activity against mouse leukemia cell lines (L-1210, P-815).  相似文献   
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Arundo donax L., commonly known as giant reed, is promising biomass feedstock that is also a notorious invasive plant in freshwater ecosystems around the world. Heretofore, the salt tolerance of A. donax had not been quantified even though anecdotal evidence suggests halophytic qualities. To test whole-plant and leaf level responses, we established a pot experiment on 80 scions propagated from an A. donax population that has naturalized on the shore of the San Francisco Bay Estuary. To quantify growth and physiological responses to salinity (NaCl), A. donax scions were divided into eight treatments and grown for 60 days across a range of salinities (0–42 dS m−1). Classic growth analysis showed >80% reduction in overall growth at the highest salinities. Yet, there was zero mortality indicating that A. donax is able to tolerate high levels of salt. Declining photosynthesis rates were strongly correlated (R2 > 0.97) with decreasing stomatal conductance, which was in turn closely related to increasing salinity. Leaf gas exchange revealed that stomata and leaf limitations of carbon dioxide were three times greater at high salinities. Nonetheless, even when salinities were 38–42 dS m−1 A. donax was able to maintain assimilation rates 7–12 μmol m−2 s−1. Further, by maintaining 50% relative growth at salinities ~12 dS m−1 A. donax can now be classified as ‘moderately salt tolerant’. A. donax leaf gas exchange and whole-plant salt tolerance are greater than many important food crops (i.e. maize, rice), the bioenergy feedstock Miscanthus × giganteus, as well as some uncultivated plant species (i.e. Populus and Salix) that are indigenous in regions A. donax currently invades. The results of this study have implications for both agronomists wishing to expand A. donax to fields dominated by saline soils, and for others who are concerned about the spread of A. donax with altered stream hydrology or sea-level rise.  相似文献   
23.
The relation between hypertension and cognition in elders remains unclear, and studies on the effect of antihypertensive drugs on cognition have demonstrated conflicting results. This study was performed to evaluate if the association between hypertension and cognition in elders differed depending on serum concentrations of organochlorine (OC) pesticides, common neurotoxic chemicals. Participants were 644 elders aged 60–85 years who participated in the National Health and Nutrition Examination Survey 1999–2002 and were able to complete a cognitive test. We selected 6 OC pesticides that were commonly detected in the elderly. Cognition was assessed by the Digit Symbol Substitution Test (DSST), a relevant tool for evaluating hypertension-related cognitive function, and low cognition was defined by the DSST score < 25th percentile. When OC pesticides were not considered in the analyses, elders with hypertension had about 1.7 times higher risk of low cognition than those without hypertension. However, in analyses stratified by serum concentrations of OC pesticides, the associations between hypertension and low cognition were stronger the higher the serum concentrations of p,p’-DDT, p,p’-DDE, β-hexachlorocyclohexane, and trans-nonachlor increased. Among elders in the 3rd tertile of these pesticides, adjusted odds ratios were from 2.5 to 3.5. In contrast, hypertension was not clearly associated with the risk of low cognition in elders in the 1st tertile of these pesticides. Similar patterns were observed for the continuous DSST score dependent variable. The difference in the association between hypertension and DSST scores according to the levels of OC pesticides suggest a key role of OC pesticides in the development of hypertension-related cognitive impairment and may help to identify hypertensive elders who are at a high risk of cognitive impairment.  相似文献   
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2-(Trimethylammonium) ethyl (R)-3-methoxy-3-oxo-2-stearamidopropyl phosphate [(R)-TEMOSPho], a derivative of an organic chemical identified from a natural product library, promotes highly efficient megakaryopoiesis. Here, we show that (R)-TEMOSPho blocks osteoclast maturation from progenitor cells of hematopoietic origin, as well as blocking the resorptive function of mature osteoclasts. The inhibitory effect of (R)-TEMOSPho on osteoclasts was due to a disruption of the actin cytoskeleton, resulting from impaired downstream signaling of c-Fms, a receptor for macrophage-colony stimulating factor linked to c-Cbl, phosphoinositol-3-kinase (PI3K), Vav3, and Rac1. In addition, (R)-TEMOSPho blocked inflammation-induced bone destruction by reducing the numbers of osteoclasts produced in mice. Thus, (R)-TEMOSPho may represent a promising new class of antiresorptive drugs for the treatment of bone loss associated with increased osteoclast maturation and activity.  相似文献   
27.
We encountered a patient with heavy Hymenolepis nana infection. The patient was a 44-year-old Korean man who had suffered from chronic hepatitis (type B) for 15 years. A large number of H. nana adult worms were found during colonoscopy that was performed as a part of routine health screening. The parasites were scattered throughout the colon, as well as in the terminal ileum, although the patient was immunocompetent. Based on this study, colonoscopy may be helpful for diagnosis of asymptomatic H. nana infections.  相似文献   
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Paternally Expressed Gene 3 (Peg3) is an imprinted gene that controls milk letdown and maternal-caring behaviors. In this study, a conditional knockout allele has been developed in Mus musculus to further characterize these known functions of Peg3 in a tissue-specific manner. The mutant line was first crossed with a germline Cre. The progeny of this cross displayed growth retardation phenotypes. This is consistent with those seen in the previous mutant lines of Peg3, confirming the usefulness of the new mutant allele. The mutant line was subsequently crossed individually with MMTV- and Nkx2.1-Cre lines to test Peg3’s roles in the mammary gland and hypothalamus, respectively. According to the results, the milk letdown process was impaired in the nursing females with the Peg3 mutation in the mammary gland, but not in the hypothalamus. This suggests that Peg3’s roles in the milk letdown process are more critical in the mammary gland than in the hypothalamus. In contrast, one of the maternal-caring behaviors, nest-building, was interrupted in the females with the mutation in both MMTV- and Nkx2.1-driven lines. Overall, this is the first study to introduce a conditional knockout allele of Peg3 and to further dissect its contribution to mammalian reproduction in a tissue-specific manner.  相似文献   
30.
Range of motion (ROM) measurements are essential for the evaluation for and diagnosis of adhesive capsulitis of the shoulder (AC). However, taking these measurements using a goniometer is inconvenient and sometimes unreliable. The Kinect (Microsoft, Seattle, WA, USA) is gaining attention as a new motion detecting device that is nonintrusive and easy to implement. This study aimed to apply Kinect to measure shoulder ROM in AC; we evaluated its validity by calculating the agreement of the measurements obtained using Kinect with those obtained using goniometer and assessed its utility for the diagnosis of AC. Both shoulders of 15 healthy volunteers and affected shoulders of 12 patients with AC were included in the study. The passive and active ROM of each were measured with a goniometer for flexion, abduction, and external rotation. Their active shoulder motions for each direction were again captured using Kinect and the ROM values were calculated. The agreement between the two measurements was tested with the intraclass correlation coefficient (ICC). Diagnostic performance using the Kinect ROM was evaluated with Cohen’s kappa value. The cutoff values of the limited ROM were determined in the following ways: the same as passive ROM values, reflecting the mean difference, and based on receiver operating characteristic curves. The ICC for flexion/abduction/external rotation between goniometric passive ROM and the Kinect ROM were 0.906/0.942/0.911, while those between active ROMs and the Kinect ROMs were 0.864/0.932/0.925. Cohen’s kappa values were 0.88, 0.88, and 1.0 with the cutoff values in the order above. Measurements of the shoulder ROM using Kinect show excellent agreement with those taken using a goniometer. These results indicate that the Kinect can be used to measure shoulder ROM and to diagnose AC as an alternative to goniometer.  相似文献   
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