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81.
The uptake of myo-inositol and its incorporation into the phosphoinositides and inositol phosphates of the phosphatidylinositol (PtdIns) signal transduction system by in vivo preimplantation cattle embryos was investigated using [(3)H] myo-inositol. Uptake of inositol was examined in two-cell and four-cell embryos (day 2 after insemination), morulae (day 6) and early blastocysts (day 7). Uptake in all stages examined was largely sodium-dependent indicating the presence of a sodium-dependent inositol transporter. Uptake of inositol did not vary significantly from two-cell to early blastocyst stages when expressed either on a per embryo or a per microg of protein basis. Incorporation of inositol into the three phosphoinositides, PtdIns, PtdInsP, and PtdInsP(2), was detectable at all stages examined. In contrast, incorporation of inositol into inositol phosphates was not detected until blastocyst formation at day 7. The second messenger, Ins(1,4,5)P(3), was first detected in day 7 blastocysts. 相似文献
82.
Balog EM Fruen BR Kane PK Louis CF 《American journal of physiology. Cell physiology》2000,278(3):C601-C611
Inorganic phosphate(Pi) accumulates in the fibers of actively working musclewhere it acts at various sites to modulate contraction. To characterizethe role of Pi as a regulator of the sarcoplasmic reticulum(SR) calcium (Ca2+) release channel, we examined the actionof Pi on purified SR Ca2+ release channels,isolated SR vesicles, and skinned skeletal muscle fibers. In singlechannel studies, addition of Pi to the cis chamberincreased single channel open probability (Po;0.079 ± 0.020 in 0 Pi, 0.157 ± 0.034 in 20 mMPi) by decreasing mean channel closed time; mean channelopen times were unaffected. In contrast, the ATP analog,,-methyleneadenosine 5'-triphosphate (AMP-PCP), enhancedPo by increasing single channel open time anddecreasing channel closed time. Pi stimulation of[3H]ryanodine binding by SR vesicles wassimilar at all concentrations of AMP-PCP, suggesting Pi andadenine nucleotides act via independent sites. In skinned musclefibers, 40 mM Pi enhanced Ca2+-inducedCa2+ release, suggesting an in situ stimulation ofthe release channel by high concentrations of Pi. Ourresults support the hypothesis that Pi may be an importantendogenous modulator of the skeletal muscle SR Ca2+ releasechannel under fatiguing conditions in vivo, acting via a mechanismdistinct from adenine nucleotides. 相似文献
83.
Analysis of hABC1 gene 5' end: additional peptide sequence, promoter region, and four polymorphisms 总被引:3,自引:0,他引:3
Pullinger CR Hakamata H Duchateau PN Eng C Aouizerat BE Cho MH Fielding CJ Kane JP 《Biochemical and biophysical research communications》2000,271(2):451-455
Evidence linking mutations in ATP-binding-cassette transporter gene 1 (ABC1) to Tangier disease suggests it functions in the active transport of free cholesterol out of cells. Since its mRNA level is regulated in response to cellular cholesterol stores it is of interest to explore its promoter response elements, and to investigate polymorphisms for their contributions to the prevalence of low levels of HDL in the population that promotes premature coronary heart disease. Investigation of the 5' end of the gene by 5' RACE analysis revealed 455 nucleotides additional to published sequences, and predicts another 60 amino acid N-terminal residues, resulting in a 2261-residue protein. Protein sequence analysis predicts a membrane-spanning region and possible signal peptide. The 5' flanking region was located by a Human Research Project BLAST search. This region contains regulatory elements that potentially control ABC1 gene expression. In addition to numerous SP1 binding sites there are four putative sterol regulatory elements (SREs). Our studies uncovered three single nucleotide substitution polymorphisms, one in the promoter region and two in the 5' untranslated region (5'UTR), plus an insertion/deletion polymorphism. 相似文献
84.
Long-term outcome of cleft lip nasal reconstruction in childhood 总被引:4,自引:0,他引:4
This study documents the pattern of unilateral cleft lip nasal reconstruction in the practice of one surgeon at a tertiary cleft center, evaluating the long-term appearance outcome of single-operation unilateral cleft lip nasal reconstruction in childhood. A retrospective medical record review was performed for all patients with a diagnosis of unilateral cleft lip and age greater than 15 years. Operative notes were reviewed, recording 15 variables identifying specific rhinoplastic maneuvers. Nasal appearance outcome analysis was performed for all patients who underwent only one nasal surgery before 12 years of age (n = 19). Standard frontal whole face photographic images were presented as opposing pairs in a looseleaf binder to two panels, 1 of 10 lay persons and 1 of 10 plastic surgeons. Each pair consisted of photographs of the same patient at different ages in one of three combinations: preoperative-perioperative, perioperative-longest postoperative, or preoperative-longest postoperative. Participants were asked to compare the appearance of the noses in the two photographs and assign a rating based on a 5-point Likert scale. Statistical analyses were performed on the data collected in the aesthetic analysis. The effect of surgery upon nasal appearance was assessed by comparing the preoperative and perioperative photographs. The effect of growth was assessed by comparing the perioperative and long-term postoperative photographs. The combined effect of surgery and growth was assessed by comparing the preoperative and long-term postoperative photographs. The data were assessed by lay and professional evaluators, together and separately, to determine whether differences existed. The majority of patients did not undergo revisional nasal surgery, whereas those who did usually had one nasal operation. Most revisional nasal surgery was performed in conjunction with other cleft-related secondary surgery. A majority of lay and professional evaluators perceived revisional nasal surgery as improving nasal appearance in the short-term and to a lesser degree in the long-term, as compared with the preoperative state. Evaluations of revisional nasal surgery are generally constant between the short-term and long-term postoperative images. Lay evaluations may be contaminated by a general decline in attractiveness with aging. Patient preference should be a major factor in the decision for nasal revision surgery. Multiple means of assessing nasal appearance outcome need to be used to validate results. Nasal appearance outcomes need to be correlated with outcomes with respect to nasal morphology and function as well as patient and parent satisfaction. 相似文献
85.
Steven E. J. Bell M. Anthony McKervey Darren Fayne Patrick Kane Dermot Diamond 《Journal of molecular modeling》1998,4(1):44-52
Molecular mechanics calculations have been used to model the geometries of the complexes of Group I metal ions with calix[n]arenes (n = 4,5). A simple procedure in which the calixarene atoms are assigned partial charges on the basis of AM1 calculations and the metal ions are allowed to bind electrostatically to the calixarenes produces surprising good results when the resulting structures are compared to known crystallographic data on the complexes. Encapsulated solvent molecules and/or counterions can be included in the calculations and, indeed, are necessary to reproduce the X-ray data. Electronic Supplementary Material available. 相似文献
86.
87.
Yibin Xiang Bradford Hirth John L. Kane Junkai Liao Kevin D. Noson Christopher Yee Gary Asmussen Maria Fitzgerald Christine Klaus Michael Booker 《Bioorganic & medicinal chemistry letters》2010,20(15):4550-4554
Building on our initial work, we have identified additional novel inhibitors of sphingosine kinase-1 (SK1). These new analogs address the shortcomings found in our previously reported compounds. Inhibitors 51 and 54 demonstrated oral bioavailability in a rat PK study. 相似文献
88.
Horizontal DNA transfer plays a major role in the evolution of bacteria. It allows them to acquire new traits rapidly and these may confer fitness advantages as the bacteria compete with others in the environment. Historically, the mechanisms of horizontal DNA transfer, chiefly conjugation, transformation and transduction, have received a great deal of attention. Less attention has been focused on the regulatory problems that may accompany the acquisition of new genes by lateral routes. How are these genes integrated into the existing regulatory circuits of the cell? Does a process of 'plug-and-play' operate, or are the new genes silenced pending the evolution of regulatory mechanisms that make their expression not only safe but also beneficial to both the gene and its new host? Recent research shows that bacterial nucleoid-associated proteins such as H-NS, HU and Fis are important contributors to the processes of regulatory integration that accompany horizontal gene transfer. A key emerging theme is the antagonism that exists between the DNA–protein–DNA bridging activity of the H-NS repressor and the DNA-bending and DNA-wrapping activities of regulatory proteins that oppose H-NS. 相似文献
89.
90.
Paul R. Torgerson José E. Hagan Federico Costa Juan Calcagno Michael Kane Martha S. Martinez-Silveira Marga G. A. Goris Claudia Stein Albert I. Ko Bernadette Abela-Ridder 《PLoS neglected tropical diseases》2015,9(10)