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71.
72.
Leigh A Compton Dru A Potash Nathan A Mundell Joey V Barnett 《Developmental dynamics》2006,235(1):82-93
During embryogenesis, epicardial cells undergo epithelial-mesenchymal transformation (EMT), invade the myocardium, and differentiate into components of the coronary vasculature, including smooth muscle cells. We tested the hypothesis that transforming growth factor-beta (TGFbeta) stimulates EMT and smooth muscle differentiation of epicardial cells. In epicardial explants, TGFbeta1 and TGFbeta2 induce loss of epithelial morphology, cytokeratin, and membrane-associated Zonula Occludens-1 and increase the smooth muscle markers calponin and caldesmon. Inhibition of activin receptor-like kinase (ALK) 5 blocks these effects, whereas constitutively active (ca) ALK5 increases cell invasion by 42%. Overexpression of Smad 3 did not mimic the effects of caALK5. Inhibition of p160 rho kinase or p38 MAP kinase prevented the loss of epithelial morphology in response to TGFbeta, whereas only inhibition of p160 rho kinase blocked TGFbeta-stimulated caldesmon expression. These data demonstrate that TGFbeta stimulates loss of epithelial character and smooth muscle differentiation in epicardial cells by means of a mechanism that requires ALK5 and p160 rho kinase. 相似文献
73.
S. Joly L. M. Compton C. Pujol Z. B. Kurago J. M. Guthmiller 《Oral microbiology and immunology》2009,24(5):353-360
Introduction: Human β-defensins (HBDs) are cationic, antimicrobial peptides produced by epithelial cells and involved in various aspects of the innate and acquired immune responses. They are expressed by oral tissues as constitutive and inducible genes. Recently, single nucleotide polymorphisms (SNPs) of β-defensins have been correlated with increased susceptibility to certain diseases. Studies have reported altered expression of β-defensins in cancers suggesting their involvement in carcinogenesis. The purpose of this study was to evaluate the regulation of HBD-1 (also published as DEFB1), HBD-2 (DEFB4) and HBD-3 (DEFB103A) ( http://www.genenames.org/index.html ) and HBD-1 SNPs in oral squamous cell carcinoma cell lines (OSCC) and healthy gingival keratinocytes.
Methods: β-defensin expression was quantitatively assessed using real-time polymerase chain reactions in OSCC and control cell lines after exposure to interleukin-1β, tumor necrosis factor-α, and interferon-γ. Control data were obtained in a previous study. DNA from 19 OSCC cell lines and 44 control subjects were extracted and the HBD-1 region spanning the 5' untranslated region to the first intron was sequenced and analysed for SNP identification and distribution.
Results: HBD-1 and HBD-2 basal messenger RNA expression were significantly lower in OSCC. In addition, the ability to be induced was significantly reduced in OSCC for all three β-defensins. Four HBD-1 SNPs were differentially distributed between cancer and control populations. Genotype distribution at the HBD-1 locus also suggested loss of heterozygosity in OSCC.
Conclusions: The genetic variation observed in OSCC compared with that in control cell lines may account for differences in β-defensin expression. These results suggest a putative role for β-defensins in carcinogenesis and indicate that β-defensins may be useful markers of OSCC. 相似文献
Methods: β-defensin expression was quantitatively assessed using real-time polymerase chain reactions in OSCC and control cell lines after exposure to interleukin-1β, tumor necrosis factor-α, and interferon-γ. Control data were obtained in a previous study. DNA from 19 OSCC cell lines and 44 control subjects were extracted and the HBD-1 region spanning the 5' untranslated region to the first intron was sequenced and analysed for SNP identification and distribution.
Results: HBD-1 and HBD-2 basal messenger RNA expression were significantly lower in OSCC. In addition, the ability to be induced was significantly reduced in OSCC for all three β-defensins. Four HBD-1 SNPs were differentially distributed between cancer and control populations. Genotype distribution at the HBD-1 locus also suggested loss of heterozygosity in OSCC.
Conclusions: The genetic variation observed in OSCC compared with that in control cell lines may account for differences in β-defensin expression. These results suggest a putative role for β-defensins in carcinogenesis and indicate that β-defensins may be useful markers of OSCC. 相似文献
74.
AC Winter K Berger JE Buring & T Kurth 《Cephalalgia : an international journal of headache》2009,29(2):269-278
We evaluated the association of body mass index (BMI) with migraine and migraine specifics in a cross-sectional study of 63 467 women aged ≥ 45 years, of whom 12 613 (19.9%) reported any history of migraine and 9195 had active migraine. Compared with women without migraine and a BMI < 23 kg/m2 , women with a BMI ≥ 35 kg/m2 had adjusted odds ratios (ORs) (95% confidence intervals) of 1.03 (0.95, 1.12) for any history of migraine. Findings were similar for active migraineurs. Women with a BMI of ≥ 35 kg/m2 had increased risk for low and high migraine frequency, with the highest estimate for women who reported daily migraine. Compared with women with the lowest associated risk (migraine frequency < 6 times/year; BMI between 27.0 and 29.9 kg/m2 ), women with a BMI ≥ 35 kg/m2 had an OR of daily migraine of 3.11 (1.12, 8.67). Among the women with active migraine, a BMI ≥ 35 kg/m2 was associated with increased risk of phonophobia and photophobia and decreased risk of a unilateral pain characteristic and migraine aura. Our data confirm previous findings that the association between BMI with migraine is limited to migraine frequency and specific migraine features. 相似文献
75.
In a retrospective study, clinical risk factors of the neonatal period were correlated with the severity of regressed retinopathy of prematurity (ROP) in a population of preterm infants (bw less than 1500 g and or gestational age less than 33 weeks). At the age of 5-11 years 134 out of 528 preterm born infants (25.4%) were found to be under ophthalmic care. Reliable information on eye fundus status could be obtained in 105 of them. Regressed ROP was found in 61, the moderate form in 48 (9.1%) and the severe form in 13 (2.5%) patients. Twelve patients (2.3%) had visual acuity of less than 0.3 on the worst eye and two (0.4%) of these patients were blind from ROP. Twenty-four clinical factors of the newborn period were correlated with the severity of regressed ROP. The results suggest that long oxygen exposure in combination with other factors interfering with retinal vasotonus are associated with the degree of the disease developed. 相似文献
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77.
Hemispheric asymmetries in global-local perception: effects of individual differences in neuroticism
This study examined the impact of neuroticism on hemispheric specialisation and interhemispheric processing using a lateralised global-local perception task. A total of 43 individuals completed the laterality task as well as a standardised personality questionnaire, and were divided by a median split into low and high neuroticism groups. Results revealed that left hemisphere specialisation for local-level processing was absent for high neurotic individuals, although the groups were similar in asymmetries for global-level processing. Regression analyses confirmed that neuroticism was inversely correlated with the magnitude of left-hemisphere advantage for local-level processing but not associated with the asymmetry for global processing. Interhemispheric processing did not differ as a function of neuroticism. Results implicate the left temporoparietal region in neuroticism, which may in turn have implications for understanding neuropsychological links between neurotic personality traits and risk for psychopathology. 相似文献
78.
Martínez-Rodríguez J Iranzo A Santamaría J Genís D Molins A Silva Y Meléndez R 《Neurología (Barcelona, Spain)》2002,17(2):113-116
Introduction: Cataplexy is one of the main narcoleptic symptoms and is characterized by sudden loss of muscle tone triggered by emotional stimuli while consciousness is mantained. Clomipramine is an effective treatment of cataplexy. Cataplexy that occurs repeatedly for hours or days is referred to as status cataplecticus.Patients: We report three adults with narcolepsy in whom cataplexy was chronically and effectively treated with clomipramine (75-150 mg/day). For diverse reasons, these three patients had an abrupt withdrawal of clomipramine, and after 2-9 days patients showed an invalidant status cataplecticus characterized by a marked increase of the frequency, duration and severity of their cataplectic attacks that were now elicited by mild emotional stimuli. After introduction of anticataplectic agents (clomipramine in two patients and fluoxetine in one patient), status cataplecticus was resolved in less than a week.Conclusion: In patients with narcolepsy, abrupt withdrawal of chronic treatment with clomipramine may be associated with status cataplecticus. This condition may be resolved with the reintroduction of anticataplectic agents. 相似文献
79.
背景:阿德福韦双酯(ADV) 是一种有效治疗野生型和耐拉米夫定乙肝病毒(HBV)的核苷酸类药物。在使用核苷酸类药物治疗慢性乙肝时,当治疗时间为 48、96、144周时,耐ADV变异体出现的累积发生率分别为0、 0.8-3%和0-5.9%。目的:研究67例对拉米夫定耐药且接受ADV治疗的慢性乙肝患者耐ADV病毒变异体的表型和基因型特点。方法:HBV DNA含量采用实时定量PCR技术。ADV变异体检测采用基质辅助激光解吸电离/飞行时间质谱为基础的基因分型 相似文献
80.