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1.
《Nucleosides, nucleotides & nucleic acids》2013,32(4):671-690
Some 4′‐C‐ethynyl‐2′‐deoxy purine nucleosides showed the most potent anti‐HIV activity among the series of 4′‐C‐substituted 2′‐deoxynucleosides whose 4′‐C‐substituents were methyl, ethyl, ethynyl and so on. Our hypothesis is that the smaller the substituent at the C‐4′ position they have, the more acceptable biological activity they show. Thus, 4′‐C‐cyano‐2′‐deoxy purine nucleosides, whose substituent is smaller than the ethynyl group, will have more potent antiviral activity. To prove our hypothesis, we planned to develop an efficient synthesis of 4′‐C‐cyano‐2′‐deoxy purine nucleosides (4′‐CNdNs) and 4′‐C‐ethynyl‐2′‐deoxy purine nucleosides (4′‐EdNs). Consequently, we succeeded in developing an efficient synthesis of six 2′‐deoxy purine nucleosides bearing either a cyano or an ethynyl group at the C‐4′ position of the sugar moiety from 2′‐deoxyadenosine and 2,6‐diaminopurine 2′‐deoxyriboside. Unfortunately, 4′‐C‐cyano derivatives showed lower activity against HIV‐1, and two 4′‐C‐ethynyl derivatives suggested high toxicity in vivo. 相似文献
2.
《Nucleosides, nucleotides & nucleic acids》2013,32(12):1815-1824
Different arabinosides and ribosides, viz. Ara‐DDA or 9(1‐β‐d‐arabinofuranosyl) 1,3‐dideazaadenine (6), Ara‐NDDP or 9(1‐β‐d‐arabinofuranosyl) 4‐nitro‐1,3‐dideazapurine (7), Ara‐DKP or 1(1‐β‐d‐arabinofuranosyl) diketopiperazine (8), Ribo‐DDA or 9(1‐β‐d‐ribofuranosyl) 1,3‐dideazaadenine (9) and Ribo‐NDDP or 9(1‐β‐d‐ribofuranosyl) 4‐nitro‐1,3‐dideazapurine (10) have been synthesized as probable antiviral agents. The arabinosides have been synthesized using the catalyst TDA‐1 that causes stereospecific formation of β‐nucleosides while a one‐pot synthesis procedure was adopted for the synthesis of the ribonucleosides where β‐anomers were obtained in higher yields. All the five nucleoside analogs have been screened for antiviral property against HIV‐1 (IIIB), HSV‐1 and 2, parainfluenza‐3, reovirus‐1 and many others. It was observed that arabinosides had greater inhibitory action than ribosides. The compound 7 or Ara‐NDDP has shown maximum inhibition of HIV‐1 replication than the rest of the molecules with an IC50 of 79.4 µg/mL. 相似文献
3.
Timothy H. Monk Daniel J. Buysse Martica Hall Eric A. Nofzinger Wesley K. Thompson Sati A. Mazumdar 《Chronobiology international》2013,30(4):831-841
Compared to younger adults, seniors (≥60 yrs) often adopt a highly regular lifestyle, perhaps as an adaptive response to age‐related changes in their sleep and circadian rhythms. At baseline, diary measures of lifestyle regularity (SRM‐5) were obtained from 104 seniors of three separate groups. Thirty‐three subjects were challenged by spousal bereavement or the need to care for a spouse at home with dementia (Challenged); 33 were suffering from formally diagnosed (DSM‐IV) insomnia (Insomnia); and 38 were healthy, well‐functioning older seniors in the second half of their eighth decade of life or later (Healthy Older). The objective of this study was to determine whether lifestyle regularity increased as a function of age within each of these three senior groups. Overall, age was significantly correlated with SRM‐5 (r=0.41, p<0.001), with the SRM score increasing by 0.67 units/decade. The same was true for the Challenged and Insomnia groups, which also showed a significant correlation between SRM and age (Challenged: r=0.48, p<0.01; Insomnia: r=0.36, p<0.05), though with a slightly faster rate of SRM increase in the Challenged (0.95 units/decade) than Insomnia (0.55 units/decade) group. Perhaps there was no correlation between age and SRM (r=0.07, n.s.) in the Healthy Older group due to the small age range, although this group did have a higher overall SRM score than the other two groups (p<0.01). The study thus confirmed that the previously observed increase in lifestyle regularity over the adult lifespan persists into later life. This may represent an adaptive behavioral response that might be used in future therapeutic approaches. 相似文献
4.
M. Arraj 《Chronobiology international》2013,30(4):795-812
The nitric oxide (NO) system is involved in the regulation of the cardiovascular system in controlling central and peripheral vascular tone and cardiac functions. It was the aim of this study to investigate in wild‐type C57BL/6 and endothelial nitric oxide synthase (eNOS) knock‐out mice (eNOS‐/‐) the contribution of NO on the circadian rhythms in heart rate (HR), motility (motor activity [MA]), and body temperature (BT) under various environmental conditions. Experiments were performed in 12∶12 h of a light:dark cycle (LD), under free‐run in total darkness (DD), and after a phase delay shift of the LD cycle by ?6 h (i.e., under simulation of a westward time zone transition). All parameters were monitored by radiotelemetry in freely moving mice. In LD, no significant differences in the rhythms of HR and MA were observed between the two strains of mice. BT, however, was significantly lower during the light phase in eNOS‐/‐ mice, resulting in a significantly greater amplitude. The period of the free‐running rhythm in DD was slightly shorter for all variables, though not significant. In general, rhythmicity was greater in eNOS‐/‐ than in C57 mice both in LD and DD. After a delay shift of the LD cycle, HR and BT were resynchronized to the new LD schedule within 5–6 days, and resynchronization of MA occurred within 2–3 days. The results in telemetrically instrumented mice show that complete knock‐out of the endothelial NO system—though expressed in the suprachiasmatic nuclei and in peripheral tissues—did not affect the circadian organization of heart rate and motility. The circadian regulation of the body temperature was slightly affected in eNOS‐/‐ mice. 相似文献
5.
《Chronobiology international》2013,30(2):353-381
24 h patterns with high frequency components in the incidence of pediatric trauma were validated and quantified in one of our earlier studies. Herein, we further explored the temporal—high frequency, 24 h, weekly (7 d), hemi‐weekly (3.5 d), and annual – patterns in traumatic (1990–1997; n=15,110 events) and non‐traumatic pediatric surgical emergencies (PSE) (1992–2001; n=5,593 events) as well as automobile accidents (AA) (1990–1997; n=67,712) in the County of Vaud, Switzerland. The latter served as a reference system of human adult activity and risk. Two‐way ANOVA, χ2, correlation, and cosinor analyses were used as statistical tools. A 24 h pattern, reproducible from year to year, was validated in traumatic and non‐traumatic PSE and AA. The 24 h patterns were not correlated and differed from one another in terms of their acrophase (peak time) and amplitude. A gender‐related difference was found only in the non‐traumatic time series for weekly (7 d) and hemi‐weekly (3.5 d) patterns. The latter were detected in boys but not girls. No statistically significant difference was found in the acrophase and amplitude between boys and girls in the temporal patterns of other periods. An annual pattern was validated in automobile accidents (acrophase: 4th of September ±37 d (SD)) and pediatric trauma (acrophase: 14th of June ±10 d), but not in non‐traumatic PSE. These results suggest that environmental modulations differ between the incidence of traumatic and non‐traumatic PSE. Presumably, the two phenomena involve different aspects of the temporal organization and/or different levels of susceptibility of a set of biological rhythms to environmental factors. 相似文献
6.
《Nucleosides, nucleotides & nucleic acids》2013,32(11):1739-1749
New acylated 5‐thio‐β‐d‐glucopyranosylimino‐disusbstituted 1,3,4‐thiadiazols 8, and 11 were prepared, via spontaneous rearrangements, by cycloaddition of the glycosyl isothiocyanate 2 with the reactive intermediates 1‐aza‐2‐azoniaallene hexachloroantimonates 4 and 6, respectively. Reaction of 2 with aminoacetone or chloroethylamine afforded the acylated 5‐thio‐β‐d‐glucopyranosyl‐4‐imidazoline‐2‐thione nucleoside 16 and glucopyranosylamino‐2‐thiazoline derivative 18, respectively. Deblocking of 8, 11, 17 and 19 furnished the free nucleoside analogues 9, 12, 18 and 20, respectively. Analogously, treatment of 2 with chloroethylamine in the 1:2 ratio afforded the thioureylendisaccharide 21. No in vitro antiviral activity against HIV‐1, HIV‐2, human cytomegallovirus (HMCV), has been found for the new synthesized compounds. 相似文献
7.
The aim of this study was to examine sex differences in sleep‐time preference by age among Italian pre‐adolescents, adolescents, and adults. The final sample consisted of 8,972 participants (5,367 females and 3,605 males) from 10 to 87 yrs of age. To assess preferred sleep habits, we considered the answers to the open‐ended questions of the Morningness‐Eveningness Questionnaire (MEQ). In agreement with previous studies, we found that sleep‐time preference started to shift toward eveningness from the age of 13 yrs. Females reached their peak in eveningness earlier (about 17 yrs of age) than males (about 21 yrs of age). Thereafter, the ideal sleep‐time preference advanced in men and women with increasing age. Females presented a more significant advanced sleep phase than males only during the years when sexual hormones are typically active. Moreover, females reported a longer ideal sleep duration than males across all age groups examined, except in over 55 yrs one. (Author correspondence: vincenzo.natale@unibo.it) 相似文献
8.
Eric P. Verrecchia 《Geomicrobiology journal》2013,30(2):87-99
Microscopic observations of calcrete soil samples in semiarid environments from Israel reveal a particular vesicular microfabric. The calcrete horizon is indurated but highly porous and all the pores are coated with a gray layer (quasi‐coating) of secondary calcium carbonate. Two kinds of needles are found inside the pores: thin and regular needles (calcite), and filaments with very sharp spikes that are of fungal origin. Analysis of the proportions of C, O, and Ca were made with an E.D.S. microprobe connected with a scanning electron microscope to distinguish calcite (CaCO3) from calcium oxalate (CaC2O4) and to differentiate inorganic from organic influences. Under biological control, calcium oxalate coexists with calcium carbonate; both contribute to rock diagenesis. In the pores, biological activity promotes a complex cycling of calcium leading to recementation of the matrix and further lithification. Thus, this kind of calcrete is due to geological evolution as much as to biochemical control. 相似文献
9.
Roger Persson Anne Helene Garde Bente Schibye Palle Ørbæk 《Chronobiology international》2013,30(6):1329-1345
Large‐scale construction work often requires people to work longer daily hours and more than the ordinary five days in a row. In order to minimize transportation times and optimize the use of personnel, workers are sometimes asked to live in temporary building‐site camps in the proximity of the work site. However, little is known about the biological and psychological effects of this experience. The objective of the present study was to investigate whether exposure to long work hours and extended workweeks while living in building‐site camps in between work shifts was associated with a build‐up of increased complaints of poor sleep, daytime sleepiness, physical exertion, and fatigue across a two‐week work cycle. Two groups of construction workers were examined. The camp group of 13 participants (mean age: 42±11 S.D. yrs) lived in building‐site camps and worked extended hours (between 07:00 and 18:00 h) and extended workweeks (six days in a row, one day off, five days in a row, nine days off). The home group of 16 participants (mean age 40±9 yrs) worked ordinary hours between 07:00 and 15:00 h and returned home after each workday. Self‐ratings of daytime sleepiness (Karolinska Sleepiness Scale), physical exertion (Borg CR‐10), and mood were obtained six or seven times daily during two workweeks. Fatigue ratings were obtained once daily in the evening, and ratings of sleep disturbances were obtained once daily in the morning with the Karolinska Sleep Diary. Data were evaluated in a repeated measures design. The results showed that both groups reported a similar level of daytime sleepiness, physical exertion, and mood across workdays and time points within a workday (all three‐way interactions had p>0.898). Although the home group reported earlier wake‐up times, the pattern of sleep disturbance ratings across the workdays did not differ between the groups. Both groups reported few sleep disturbances and good mood. However, the camp group reported higher physical exertion already at the start of work and showed a more gentle increase in ratings during the work shift and a smaller decline between the end of work and bedtime. The camp group also reported higher fatigue scores than the home group. However, none of the groups showed signs of increasing ratings in the progress of the two workweeks. For both groups, the ratings of daytime sleepiness formed a U‐shaped pattern, with the highest scores at awakening and at bedtime. Yet, the camp group reported higher daytime sleepiness than the home group at lunch break and at the second break in the afternoon. In conclusion, there were no signs of fatigue build‐up or accumulation of daytime sleepiness, physical exertion, or sleep disturbances in either group. Despite the fact that the camp group showed some signs of having trouble in recuperating in between work shifts, as indicated by the higher physical exertion ratings at the start of work, higher fatigue scores, and higher daytime sleepiness, the results constitute no real foundation for altering the camp group's current work schedule and living arrangements. 相似文献
10.
《Nucleosides, nucleotides & nucleic acids》2013,32(3):599-611
The method of synthesizing acyclonucleoside iron chelators is both convenient and cost effective compared to that of synthesizing ribonucleoside iron chelators. The X‐ray crystal structural analysis shows that the 2‐hydroxyethoxymethyl group does not affect the geometry of the iron chelating sites. Therefore, the iron binding and removal properties of the acyclonucleoside iron chelators should remain similar to the ribonucleoside iron chelators, which is confirmed by the titration and competition reaction of the acyclonucleoside chelators with iron and ferritin, respectively. The acyclonucleoside iron chelators are more lipophilic with measured n‐octanol and Tris buffer distribution coefficients than ribonucleoside iron chelators. 相似文献
11.
Carl‐Ulrik Schierup 《Ethnos》2013,78(3-4):173-198
This article analyzes the role of self‐control, moral and ethical doctrines in the rise of individualist world‐view in Finland. In the Finnish case, the formation of the modern individual was closely linked with the temperance movement, the ideology of which is therefore used as an illustrative example. The guiding line in the article is not to treat self‐control as a theoretical concept used in analyzing individual behavior, but as a legitimation of an increasing use of a utilitarian framework. The author discusses the developments in Finnish individualist world‐view by analyzing the main turning points in Finnish notions about drinking. First he discusses the end of the 19th century and the beginning of the 20th century, the era of the strength of Finnish temperance movement. Secondly he analyzes the way in which conceptions about drinking changed when the temperance movement lost its appeal to the masses. 相似文献
12.
13.
Jane Desmond 《Visual Anthropology: Published in cooperation with the Commission on Visual Anthropology》2013,26(2):147-160
Drawing on the work of Edward Said and James Clifford, this article discusses the theoretical and practical possibilities for producing images of “otherness” which do not participate in an Orientalist discourse. Works by two avant‐garde filmmakers, Leslie Thornton and Trinh T. Minh‐ha, are examined in the light of these theoretical discussions. While avant‐garde film practice is no guarantee of escaping the pitfalls of Orientalism or cultural relativism, selective viewing of avant‐garde work may provide useful models for visual production. 相似文献
14.
《Nucleosides, nucleotides & nucleic acids》2013,32(11):1767-1777
Oligoribonucleotides containing 4‐thiouridine were prepared using the Fpmp group for protection of the 2′‐OH. Two uridine derivatives with the 1,2,4‐triazolyl and the 2‐nitrophenyl groups at position 4 were used to obtain 4‐thiouridine by postsynthetic substitution with sodium hydrogen sulfide. Both uridine derivatives allow the preparation of the desired oligonucleotides in good yields. 相似文献
15.
Abstract New data are reported on the diet of the long‐finned pilot whale, Globicephala melas, based on stomach contents recovered from whales involved in a mass stranding on Farewell Spit, Golden Bay, South Island, on 23 January 2008. The stomachs of 11 whales were examined, from which identifiable prey remains were recovered from six, four females and two males (3.1–5.4 m in length). Prey remains comprised exclusively cephalopod beaks (1–46 beaks per whale), attributed to two genera in two orders: arrow squid, Nototodarus spp. (Teuthoidea: Ommastrephidae), and common octopus, Pinnoctopus cordiformis (Octopoda: Octopodidae). The stomachs of eight whales were infested with parasitic nematodes, with two ulcerated; the stomachs of five whales did not contain any prey remains. These data complement and are comparable to the only other information available for this species from this region, reported from whales mass‐stranded at this same location in December 2005. Lower beak rostral length versus mantle length and biomass regression equations for Nototodarus spp. are reviewed, highlighting the importance of the use of species‐specific regression equations for reconstructing both cephalopod mantle length and biomass from lower beak remains in dietary studies. 相似文献
16.
《Nucleosides, nucleotides & nucleic acids》2013,32(1-2):127-136
Two new types of imidazole derivatives: N‐(2‐R1‐5‐R2‐1H‐imidazol‐4‐yl) thioureas 7a–g and N‐(2‐R1‐5‐R2‐1H‐imidazol‐4‐yl) formamides 8b,c,g were obtained in high yields by the hydrolytic degradation of 6‐R1‐8‐R2‐2‐thioxo‐2,3‐dihydroimidazo[1,5‐a]‐1,3,5‐triazin‐4(1H)‐ones 5a–g and 6‐R1‐8‐R2‐imidazo[1,5‐a]‐1,3,5‐triazin‐4(3H)‐ones 6b,c,d, respectively. The tautomeric preferences of the new imidazoles were determined. 相似文献
17.
《Nucleosides, nucleotides & nucleic acids》2013,32(11):1707-1721
Synthesis of pyrimidine derivatives with a side‐chain attached to the C‐6 of pyrimidine ring (6–14) is reported. Target compounds 8 and 12 were subjected to in vitro phosphorylation tests, determination of their binding affinities to herpes simplex virus (HSV‐1) thymidine kinase (TK) and catalytic turnover constants. Fluorinated pyrimidine derivative 12 (40 µM) exhibited better binding affinity for HSV‐1 TK than acyclovir (ACV, 170 µM) and ganciclovir (GCV, 48 µM). Catalytic turnover constant (k cat) of 12 (0.08 s? 1) was close to the k cat values of ACV (0.10 s? 1) and GCV (0.10 s? 1). Furthermore, compounds 8 and 12 showed no cytotoxic effects in HSV‐1 TK‐transduced and non‐transduced cell lines. Besides, compounds 8 and 12 did not exhibit antiviral or cytostatic activities against several viruses and malignant tumor cell lines that were evaluated. The new fluorinated pyrimidine derivative 16 that is phosphorylated by HSV‐1 TK could be developed as non‐toxic PET‐tracer molecule. Thus, 18F labelling of the precursor 14 was performed by nucleophilic substitution using [18F] tetrabutylammonium fluoride as the fluorinating reagent. 相似文献
18.
《Biodemography and social biology》2013,59(3-4):171-185
Abstract Vital statistics data show a remarkably consistent seasonality in U.S. birth patterns, with peaks in late summer and winter months, and a valley in the spring. An attitude survey of college students suggests that peaks in the actual birth distribution occur in unpopular months in which to give birth; the valley in the actual birth distribution occurs in popular months. This paradoxical finding is named the Season‐of‐Birth Paradox. Explanations to resolve the paradox include biological and psychological components. A psychological mechanism—named the Misinformed Reproducer Hypothesis—is tested using NSFG data from the 1973–75 and 1979–81 cycles. Results suggest that women stop contracepting with the expectation that they will get pregnant almost immediately. When it takes several months on the average for a successful conception to occur, the actual birth distribution is shifted away from the preferred birth distribution. These results suggest that psychological as well as biological mechanisms underlie the consistent seasonality patterns in U.S. births. 相似文献
19.
Eocene lake sediments from Horsefly, British Columbia are rich in fossils of the catostomid fish Amyzon aggregatum. Previous studies of this fish in a 700‐year sequence of varves have demonstrated their potential use in studies of fine‐scale temporal variation in taphonomy and morphology. Tests of the annual (varve) hypothesis for the layers, together with reliable temporal calibration, are necessary prerequisites to any such application. In the present study, a longer continuous sequence from this deposit is subjected to additional tests of the annual hypothesis and is temporally calibrated. Tests include spectral analysis of varve thicknesses, scanning electron microscopy and elemental analysis of dark and light laminae, and analysis of within‐couplet distribution of seasonal fossils. Results support the hypothesis that the couplets are true varves. Some 6375 varves occur in the studied interval. Each varve is composed of a diatom‐dominated summer lamina and a winter lamina richer in clays, pyrite, and gypsum. Occasional turbidites and thin layers of volcanic ash allow counting and identification of individual varves under low‐power magnification. Fish are rare in the upper 2000 varves but abundant and extensively distributed in the lower 4000 varves of the sequence, making these a potentially valuable interval for studies of microstratigraphic variation in morphology and taphonomy. 相似文献
20.
《Nucleosides, nucleotides & nucleic acids》2013,32(4):715-724
In view of biological activities of azole nucleosides and apio‐dideoxynucleoside, novel apio nucleoside analogues (1 and 2) with thiazole and triazole base moiety were synthesized using 2,3‐O‐isopropylidene‐apio‐β‐d‐furanose (3), which was prepared from d‐mannose. 相似文献