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51.
Objective: To evaluate the frequencies of fetal facial expressions among appropriate-for-gestational-age (AGA), small-for-gestational-age (SGA), and growth-restricted (FGR) fetuses.

Methods: Four-dimensional (4D) ultrasound was used to examine the facial expressions of 50 AGA, 25 SGA, and six FGR fetuses between 28 and 35 weeks of gestation. The frequencies of seven facial expressions during 15-minute recordings were assessed. Comparison of facial expressions among the three groups was performed.

Results: Mouthing was the commonest facial expression at 28–35 weeks, and the frequency of mouthing was significantly higher than those of the other six facial expressions in AGA fetuses. Mouthing was the most frequent facial expression, but there was no significant difference in the frequency among mouthing, smiling and blinking in SGA fetuses. Moreover, mouthing displayed a significantly higher frequency than the other facial expressions, except for yawning, smiling, and blinking in FGR fetuses. However, there was no significant difference in the frequency of each facial expression among the three groups.

Conclusions: Our results suggest that the frequencies of fetal facial expressions are not decreased in either SGA or FGR pregnancies. The absence of a decrease in the frequency of each fetal expression in FGR fetuses may be due to increased brain blood flow because of the brain-sparing effect. Moreover, accelerated maturation and development of the brain function, especially the central dopamine system, might be suspected in SGA and FGR fetuses.  相似文献   

52.
Background : The tsBN7 cell line is one of the temperature-sensitive mutants for cell proliferation which have been isolated from the BHK21 cell line derived from the golden hamster. It has a mutation in the DAD1 gene encoding a 12.5 kDa highly conserved protein through evolution, and enters apoptosis at the restrictive temperature due to this mutation.
Results : DAD1 was recovered in light membrane fractions after differential centrifugation. It could not be released from the membrane, even by carbonate extraction, without a detergent. Upon digestion with proteinase K, both N and C terminal portions—but not the middle portions of DAD1—were released from the membrane. Thus, DAD1 appears to be an integral membrane protein in which both termini are located in the cytosol. DAD1 was localized in the endoplasmic reticulum. In accordance with a similarity to the yeast protein Ost2p, which is a subunit of the oligosaccharyltransferase, at the restrictive temperature, loss of DAD1 function caused a defect of N-linked glycosylation in tsBN7 cells resulting in apoptosis. However, tunicamycin, which is known to inhibit N-linked glycosylation did not induce apoptosis in either tsBN7 or BHK21 cells.
Conclusion : tsBN7 cells have a defect in N-linked glycosylation caused by the loss of DAD1.  相似文献   
53.
We determined the distribution of DR4 subtypes in 309 DQB1*0302-positive haplotypes found in insulin-dependent diabetes mellitus (IDDM) patients and 70 control haplotypes present only in healthy family members. An increased frequency of DRB1*0401 allele (74.4% vs. 55.7%, P = 0.003) and a decrease of DRB1*0404 allele (23.6% vs. 40.0%, P = 0.0064) was revealed. A further analysis of extended haplotypes demonstrated strong linkages between various B alleles and DRB1*04 subtypes. HLA-B39 was more frequent in DRB1*0404–DQB1*0302-positive IDDM haplotypes compared with control ones (37.0% vs. 14.3%, P = 0.049), suggesting an involvement of the region telomeric to HLA-DRB1 in the susceptibility to IDDM.  相似文献   
54.
55.
BACKGROUND: Although uterine leiomyomas or fibroids are the most common gynecological benign tumor and greatly affect reproductive health and well-being, the pathophysiology and epidemiology of uterine leiomyomas are poorly understood. Elevated blood pressure has an independent, positive association with risk for clinically detected uterine leiomyoma. Angiotensin II (Ang II) is a key biological peptide in the renin-angiotensin system that regulates blood pressure. METHODS: In this study, we investigated the potential role of Ang II (1-1000 nM) in the proliferation of rat ELT-3 leiomyoma cells in vitro. RT-PCR and western blot analysis with cell proliferation and DNA transfection assays were performed to determine the mechanism of action of Ang II. RESULTS: Ang II induced ELT-3 leiomyoma cell proliferation (P < 0.01) and the expression of Ang II type 1 receptor (AT(1)R) and AT(2)R mRNA and protein was confirmed. Regarding the intracellular signaling pathway, the Ang II-induced cell proliferation was AT(1)R-, epidermal growth factor receptor-, extracellular-regulated kinase- and protein kinase C-dependent but was not dependent on the AT(2)R or phosphatidylinositol-3 kinase or JAK kinase. The AT(1)R blocker telmisartan, effectively repressed Ang II-induced and estradiol-induced cell proliferation (P < 0.01). AT(1)R, but not AT(2)R, plays a role in Ang II-induced ELT-3 cell proliferation. CONCLUSIONS: These experimental findings in vitro highlight the potential role of Ang II in the proliferation of leiomyoma cells.  相似文献   
56.
Adult Still's disease reflects a Th2 rather than a Th1 cytokine profile   总被引:2,自引:0,他引:2  
Adult Still's disease (ASD) is a chronic multisystemic disease. Extraordinarily high serum levels of IL-18 in ASD patients have been described, whereas the mechanism remains to be clarified. This study aimed to evaluate proinflammatory cytokines and to consider their pathological roles. In patients with rheumatic diseases (n = 151), blood samples were taken at the active phase and the serum levels of IL-18 and other proinflammatory cytokines were measured by ELISA. The extra-high levels of IL-18 were confirmed selectively in ASD patients (n = 10). In the active phase of ASD patients, the levels of IL-6 were elevated accordingly, but IL-1beta and TNF-alpha were undetectable. As to Th1-Th2 cytokines, the levels of IL-4 and IL-13, but not INF-gamma, IL-12, or IL-2, were elevated in all ASD patients examined. Moreover, the serum levels of IL-18 showed a good correlation with those of IL-4, suggesting that ASD reflects a Th2 rather than a Th1 cytokine profile.  相似文献   
57.
Background: We have previously isolated a series of temperature-sensitive mutants for cell-proliferation from the BHK21 cell line, derived from the golden hamster. These mutants proliferate at 33.5 °C, the permissive temperature, but not at 39.5 °C the restrictive temperature. Using DNA-mediated gene transfer, human genes complementing these ts mutants were cloned.
Results: At 39.5 °C the tsBN250 cell line, a temperature-sensitive mutant of the BHK21 cell line, had a defect in the G1 phase, but not in the S phase. The human gene complementing tsBN250 cells was found to encode histidyl-tRNA synthetase. Indeed, the tsBN250 cell line had a single base change—guanine to adenine at the second position of the 362nd codon of hamster histidyl-tRNA-synthetase, converting arginine to histidine. Following release from serum starvation, cyclin E, but not cyclin D1, was accumulated, while, at 39.5 °C, the mRNA of cyclin D1 was normally expressed in tsBN250 cells. A similar inhibition of cyclin D1 accumulation was observed in another ts mutant, tsBN269, which has a single point mutation in lysyl-tRNA synthetase. Overexpression of cyclin D1 enabled tsBN250 cells to enter the S phase.
Conclusion: tsBN250 cells have a single point mutation in histidyl tRNA synthetase that causes a loss of histidyl-tRNA synthetase activity which in turn reduces the content of cyclin D1, but not of cyclin E, thereby resulting in G1 arrest.  相似文献   
58.
目的 探讨黏液瘤病毒对大鼠动物模型体内胶质瘤细胞的作用.方法 采用立体定向法向SD大鼠颅内注射C6细胞建立大鼠额叶胶质瘤模型,明确成瘤后,随机分组,以立体定向方法往瘤腔内注射黏液瘤病毒(MV),5-FU,MV+ 5-FU及灭活黏液瘤病毒(DV),观察不同组别间大鼠体重、肿瘤大小、GFAP表达、Akt表达情况.结果 SD大鼠注射C6细胞后,额叶可见胶质瘤生长.成瘤后瘤腔内注射MV、5-FU及MV+ 5-FU,肿瘤的生长较注射DV减慢,并有缩小趋势,GFAP表达较少.MV组及MV+ 5-FU组PI3k、Akt及mTOR表达较DV组及5-FU组下降.结论 立体定向法注射C6细胞可以建立稳定的胶质瘤模型.MV可以通过调节PI3K-Akt-mTOR通路相关基因的表达,从而增加化疗药物对动物模型体内肿瘤细胞的生物学活性.  相似文献   
59.
We used dynamic dense noise stimuli and local spectral reverse correlation methods to reveal the local sensitivities of neurons in visual area 2 (V2) of macaque monkeys to orientation and spatial frequency within their receptive fields. This minimized the potentially confounding assumptions that are inherent in stimulus selections. The majority of neurons exhibited a relatively high degree of homogeneity for the preferred orientations and spatial frequencies in the spatial matrix of facilitatory subfields. However, about 20% of all neurons showed maximum orientation differences between neighboring subfields that were greater than 25 deg. The neurons preferring horizontal or vertical orientations showed less inhomogeneity in space than the neurons preferring oblique orientations. Over 50% of all units also exhibited suppressive profiles, and those were more heterogeneous than facilitatory profiles. The preferred orientation and spatial frequency of suppressive profiles differed substantially from those of facilitatory profiles, and the neurons with suppressive subfields had greater orientation selectivity than those without suppressive subfields. The peak suppression occurred with longer delays than the peak facilitation. These results suggest that the receptive field profiles of the majority of V2 neurons reflect the orderly convergence of V1 inputs over space, but that a subset of V2 neurons exhibit more complex response profiles having both suppressive and facilitatory subfields. These V2 neurons with heterogeneous subfield profiles could play an important role in the initial processing of complex stimulus features.  相似文献   
60.
Human cultured periosteal sheets, which are developed from small excised periosteum tissue segments (PTSs) in culture dishes by simple expansion culture, have been applied as a promising autologous osteogenic grafting material for periodontal regenerative therapy. However, the weak initial adhesion of PTSs to dish surfaces often hampers cellular outgrowth and limits the number of preparations. To correct this weakness and still avoid the use of animal-derived adhesion biomolecules, we have developed a novel, biodegradable, porous poly(L-lactic acid) (pPLLA) membrane. Freshly excised PTSs bound well to the highly porous pPLLA membrane, possibly due to the presence of semihemispheric 20-30 μm diameter openings on the upper surface. Global gene expression analysis demonstrated that periosteal sheets cultured on pPLLA membranes upregulated expression of many adhesion molecules. Osteogenic induction stimulated the production of proteoglycans by these cells and concomitantly enhanced their expansion and penetration into the deep pore regions of the membrane in parallel with the progression of in vitro mineralization. These findings suggest that our pPLLA membranes not only facilitate initial adhesion, primarily mediated by adsorbed proteins, but also enhance biological adhesion by inducing endogenous adhesion molecules in periosteal sheet cultures. Therefore, the efficacy of periosteal sheets in therapy should be greatly enhanced by using this new pPLLA membrane.  相似文献   
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