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51.
52.
Although studies have reported the effects of the menstrual cycle on melatonin rhythmicity, none has investigated the effects of menopause on the melatonin rhythm. The circadian rhythm in melatonin and its relationship to subjective alertness was investigated in pre- and postmenopausal women under constant routine conditions (controlled posture, dim lighting, calorie intake, temperature, and prolonged wakefulness). Eleven healthy pre-menopausal (42+/-4 yr) and 10 postmenopausal women (55+/-2 yr) participated in the study. Salivary melatonin samples and subjective measures of alertness and sleepiness were assessed hourly during the 22 h constant routine protocol. Postmenopausal women had a significantly earlier melatonin acrophase (1.1+/-0.5 h clock time in decimal h; mean+/-SEM, p<0.05) compared to the pre-menopausal women (2.3+/-0.3 h). There was no significant difference between melatonin onset and amplitude between the pre-menopausal and postmenopausal women. Self-rated alertness declined in both study groups as the length of sleep deprivation increased. Melatonin onset preceded the onset of self-rated sleepiness in both groups. The time interval between melatonin onset and the onset of sleepiness and alertness offset was significantly greater in the postmenopausal women compared to the pre-menopausal women. In conclusion, under controlled experimental conditions the timing of the melatonin rhythm was advanced in postmenopausal women altering its phase relationship to subjective alertness and sleepiness. 相似文献
53.
The endoplasmic reticulum (ER) is an extremely plastic and dynamic organelle. Its size and shape can undergo drastic changes to meet changing demands for ER-related functions, or as a response to drugs or pathogens. Because of the ER's key functions in protein and lipid synthesis, this organelle is a hotbed of detailed molecular analysis. 相似文献
54.
Mathews I Schwarzenbacher R McMullan D Abdubek P Ambing E Axelrod H Biorac T Canaves JM Chiu HJ Deacon AM DiDonato M Elsliger MA Godzik A Grittini C Grzechnik SK Hale J Hampton E Han GW Haugen J Hornsby M Jaroszewski L Klock HE Koesema E Kreusch A Kuhn P Lesley SA Levin I Miller MD Moy K Nigoghossian E Ouyang J Paulsen J Quijano K Reyes R Spraggon G Stevens RC van den Bedem H Velasquez J Vincent J White A Wolf G Xu Q Hodgson KO Wooley J Wilson IA 《Proteins》2005,59(4):869-874
55.
Rife C Schwarzenbacher R McMullan D Abdubek P Ambing E Axelrod H Biorac T Canaves JM Chiu HJ Deacon AM DiDonato M Elsliger MA Godzik A Grittini C Grzechnik SK Hale J Hampton E Han GW Haugen J Hornsby M Jaroszewski L Klock HE Koesema E Kreusch A Kuhn P Lesley SA Miller MD Moy K Nigoghossian E Paulsen J Quijano K Reyes R Sims E Spraggon G Stevens RC van den Bedem H Velasquez J Vincent J White A Wolf G Xu Q Hodgson KO Wooley J Wilson IA 《Proteins》2005,61(2):444-448
56.
Neutrophil oxidants are hypothesized to damage the gastric mucosa and promote carcinogenesis in people infected with Helicobacter pylori. To investigate this process we used wild-type and chronic granulomatous disease (CGD) mice with a targeted disruption of the gp91(phox) subunit of the NADPH oxidase. The mice were inoculated with a mouse-adapted strain of H. pylori and changes in gastric pathology were examined 12 and 30 weeks after infection. Glandular atrophy, a precursor lesion in the development of intestinal-type gastric carcinoma, and epithelial cell proliferation were both dramatically increased in the gastric body of CGD animals within 12 weeks. This correlated strongly with increased numbers of neutrophils in the mucosa (Pearson coefficient 0.97, P < 0.001). H. pylori is a noninvasive bacterium, and there was no increase in bacterial numbers in the CGD animals. Closer examination of the gastric tissue indicated the presence of degenerate neutrophils associated with atrophy. We hypothesize that the release of granule constituents from these neutrophils contributes to tissue damage. This is exacerbated by the absence of a functional NADPH oxidase, and is consistent with this enzyme complex having an important role in dampening the inflammatory response. 相似文献
57.
M Matsuda A Tazumi S Kagawa T Sekizuka O Murayama JE Moore BC Millar 《BMC veterinary research》2006,2(1):1-4
Background
At present, six accessible sequences of 16S rDNA from Taylorella equigenitalis (T. equigenitalis) are available, whose sequence differences occur at a few nucleotide positions. Thus it is important to determine these sequences from additional strains in other countries, if possible, in order to clarify any anomalies regarding 16S rDNA sequence heterogeneity. Here, we clone and sequence the approximate full-length 16S rDNA from additional strains of T. equigenitalis isolated in Japan, Australia and France and compare these sequences to the existing published sequences.Results
Clarification of any anomalies regarding 16S rDNA sequence heterogeneity of T. equigenitalis was carried out. When cloning, sequencing and comparison of the approximate full-length 16S rDNA from 17 strains of T. equigenitalis isolated in Japan, Australia and France, nucleotide sequence differences were demonstrated at the six loci in the 1,469 nucleotide sequence. Moreover, 12 polymorphic sites occurred among 23 sequences of the 16S rDNA, including the six reference sequences.Conclusion
High sequence similarity (99.5% or more) was observed throughout, except from nucleotide positions 138 to 501 where substitutions and deletions were noted. 相似文献58.
DiDonato M Krishna SS Schwarzenbacher R McMullan D Jaroszewski L Miller MD Abdubek P Agarwalla S Ambing E Axelrod H Biorac T Chiu HJ Deacon AM Elsliger MA Feuerhelm J Godzik A Grittini C Grzechnik SK Hale J Hampton E Haugen J Hornsby M Klock HE Knuth MW Koesema E Kreusch A Kuhn P Lesley SA Moy K Nigoghossian E Okach L Paulsen J Quijano K Reyes R Rife C Spraggon G Stevens RC van den Bedem H Velasquez J White A Wolf G Xu Q Hodgson KO Wooley J Wilson IA 《Proteins》2006,63(1):256-260
59.
Mathews II Krishna SS Schwarzenbacher R McMullan D Jaroszewski L Miller MD Abdubek P Agarwalla S Ambing E Axelrod HL Canaves JM Carlton D Chiu HJ Clayton T DiDonato M Duan L Elsliger MA Grzechnik SK Hale J Hampton E Haugen J Jin KK Klock HE Koesema E Kovarik JS Kreusch A Kuhn P Levin I Morse AT Nigoghossian E Okach L Oommachen S Paulsen J Quijano K Reyes R Rife CL Spraggon G Stevens RC van den Bedem H White A Wolf G Xu Q Hodgson KO Wooley J Deacon AM Godzik A Lesley SA Wilson IA 《Proteins》2006,65(1):249-254
60.
Han GW Sri Krishna S Schwarzenbacher R McMullan D Ginalski K Elsliger MA Brittain SM Abdubek P Agarwalla S Ambing E Astakhova T Axelrod H Canaves JM Chiu HJ DiDonato M Grzechnik SK Hale J Hampton E Haugen J Jaroszewski L Jin KK Klock HE Knuth MW Koesema E Kreusch A Kuhn P Miller MD Morse AT Moy K Nigoghossian E Oommachen S Ouyang J Paulsen J Quijano K Reyes R Rife C Spraggon G Stevens RC van den Bedem H Velasquez J Wang X West B White A Wolf G Xu Q Hodgson KO Wooley J Deacon AM Godzik A 《Proteins》2006,64(4):1083-1090