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71.
Charles R. Flynn Joyce Cheung-flynn Christopher C. Smoke David Lowry Robert Roberson Michael R. Sheller Colleen M. Brophy 《Journal of pharmaceutical sciences》2010,99(7):3100-3121
A challenge in advanced drug delivery is selectively traversing the plasma membrane, a barrier that prohibits the intracellular delivery of most peptide and nucleic acid-based therapeutics. A variety of short amino acid sequences termed protein transduction domains (PTDs) first identified in viral proteins have been utilized for over 20 years to deliver proteins nondestructively into cells, however, the mechanisms by which this occurs are varied and cell-specific. Here we describe the results of live cell imaging experiments with AZX100, a cell-permeable anti-fibrotic peptide bearing an “enhanced” PTD (PTD4). We monitored fluorescently labeled AZX100 upon cell surface binding and subsequent intracellular trafficking in the presence of cellular process inhibitors and various well-defined fluorescently labeled cargos. We conclude that AZX100 enters cells via caveolae rapidly, in a manner that is independent of glycoconjugates, actin/microtubule polymerization, dynamins, multiple GTPases, and clathrin, but is associated with lipid rafts as revealed by methyl-β-cylodextrin. AZX100 treatment increases the expression of phospho-caveolin (Y14), a critical effector of focal adhesion dynamics, suggesting a mechanistic link between caveolin-1 phosphorylation and actin cytoskeleton dynamics. Our results reveal novel and interesting properties of PTD4 and offer new insight into the cellular mechanisms facilitating an advanced drug delivery tool. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:3100–3121, 2010 相似文献
72.
辅助生殖技术的迅速发展使众多不孕症患者借助体外受精-胚胎移植(IVF-ET)及其衍生技术获得了后代。然而很大一部分妇女经历多次优质胚胎移植亦不能获得妊娠,反复种植失败(RIF)已经成为阻碍妊娠率进一步提高的瓶颈问题,且日益受到生殖医学界的广泛关注。就目前的条件而言,对RIF患者给予药物或者机械操作以提高子宫内膜容受性,行宫腹腔镜检查排除宫腔及盆腔病变以改善胚胎种植环境,通过辅助孵化、选择性囊胚移植、植入前胚胎遗传学筛查、共培养等技术提高胚胎着床能力都有可能改善和提高其种植率及妊娠率。RIF成为了我们亟待解决的问题,现综述近年有关反复种植失败的相关对策新进展。 相似文献
73.
目的:探讨经颅多谱勒超声(TCD)在颈椎病(椎动脉型)所致位置性缺血性眩晕中的诊断价值.方法:利用TCD对颈椎病所致位置性缺血性眩晕76例患者进行双侧大脑后动脉(PCA)的平均血流速度分析,并结合转颈试验,探测双侧PCA平均血流速的动态变化情况.结果:颈椎病所致位置性缺血性眩晕患者当头侧向转动时,双侧PCA的平均血流速度暂时性降低,当头转回中立位时,平均血流速度逐渐回升.结论:TCD有助于识别位置性眩晕中的真性位置性缺血患者,是一种无创、简便、价廉、可靠,并可床旁操作和提供实时动态血流动力学资料的重要检查方法. 相似文献
74.
内蒙古自治区智力残疾现患率调查及病因分析 总被引:1,自引:0,他引:1
目的:了解内蒙古自治区智力残疾(mental retardation.MR)的现患率及其分布特点,分析其主要致残原因构成特点,探讨预防治疗措施。方法:采用概率比例、多阶段分层整群抽样方法进行现况调查及病例对照研究,根据年龄分别使用丹佛发育筛查测验及《7岁以上人群残疾筛查问卷》筛查,分别使用Gesell发育诊断量表及韦氏儿童智力量表简式(WISC-CR),韦氏成人智力量表简式(WAIS-RC)进行智力诊断,采用SPSS11.0软件对数据进行统计分析。结果:①内蒙古自治区智力残疾患者的现患率为4.95‰,男性MR现患率高于女性(χ2=6.28,df=1,P<0.05),农村MR的现患率明显高于城市(χ2=60.035,df=1,P<0.01)。②内蒙古自治区智力残疾致残原因以疾病(29.26%)和遗传因素(23.79%)为主。③在18岁之前(智力发育期)发现智力残疾的占74.53%,且以0~3岁发现智力残疾的人数比例最高(48.84%)。结论:智力残疾的防治重点应在农村,预防应以疾病(主要包括脑疾病、内分泌障碍、惊厥性疾病)及遗传因素为主。强调早期发现、早期干预。 相似文献
75.
Clinical, metabolic, and antibody responses of adult volunteers to an investigational vaccine composed of pertussis toxin inactivated by hydrogen peroxide 总被引:10,自引:0,他引:10
R D Sekura Y L Zhang R Roberson B Acton B Trollfors N Tolson J Shiloach D Bryla J Muir-Nash D Koeller 《The Journal of pediatrics》1988,113(5):806-813
A toxoid vaccine, composed of purified pertussis toxin inactivated with H2O2 (NICHD-Ptxd), was developed on the basis of evidence that serum neutralizing antibodies (antitoxin) would confer immunity to pertussis. In vivo and in vitro assays of NICHD-Ptxd showed only trace or nondetectable levels of pyrogenic, adenosine diphosphate-ribosyltransferase, binding and pharmacologic activities. Nevertheless, about 40% of the antigenicity of pertussis toxin was retained. Adult volunteers were injected, two times 6 weeks apart, with either 10 (n = 21), 50 (n = 25), or 75 (n = 30) micrograms/dose of one lot, Ptx-06, adsorbed onto AI(OH)3. Neither fever nor changes in the levels of leukocytes, lymphocytes, fasting blood glucose, or insulin were observed in the volunteers. The optimal immunizing dose, 50 micrograms, induced levels of antitoxin (geometric mean (GM) 302 U) comparable to those found in eight adults convalescent from pertussis (GM 269 U) and greater than those found in 18-month-old children after their fourth dose of diphtheria and tetanus toxoids and pertussis vaccine (GM 20.0 U, p less than 0.001). These data indicate that NICHD-Ptxd is safe and immunogenic in adults, and they justify its evaluation in infants and children. 相似文献
76.
CARLO LA VECCHIA SILVIA FRANCESCHI FABIO PARAZZINI ELENA COLOMBO FABIO COLOMBO ALESSANDRO LIBERATI COSTANTINO MANGIONI 《BJOG : an international journal of obstetrics and gynaecology》1983,90(7):654-661
Summary. Between 1970 and 1976, 290 patients with endometrial cancer were treated at the 1st Obstetrics and Gynecology Clinic of the University of Milan. The median age was 62 years. Surgery was completed in 262 (90.3%) patients. Abdominal hysterectomy was used in 158 (70.9%) stage I and 40 (71.4%) stage II/III patients; vaginal hysterectomy in 55 (24.7%) stage I and nine (16.1%) stage II/III patients. Resection of the upper vagina was performed in 168 patients. Postoperative external beam radiotherapy was used in stage II/III patients and in 44 (19.7%) stage I high-risk patients. Ten-year survival, determined by the life-table method, was 84.8% in stage I (223 patients), 53.4% in stage II (37 patients), 64.4% in stage III (19 patients), and 9.1% in stage IV (11 patients). Factors associated with poorer prognosis were: late age at diagnosis (P<0.001); deep myometrial invasion (P<0.001); poorly differentiated histological grade ( P =0.11); lack of resection of the upper vagina ( P = 0.13). The role and importance of surgery is discussed, with special emphasis on the selective use of the vaginal route in aged, obese and medically high-risk patients. 相似文献
77.
78.
Sunil Puria Larisa D Kunda Joseph B Roberson Rodney C Perkins 《Otology & neurotology》2005,26(3):368-379
AIMS: To determine 1) the best position for hydroxylapatite malleus-to-footplate (MFP), ossicular replacement prosthesis (ORP) in reconstructed ears, and 2) whether preserving the stapes superstructure (SS), when present, has acoustic advantages. BACKGROUND: Positioning of the MFP-ORP head beneath the neck of the malleus may produce maximal force, whereas positioning beneath the manubrium of the malleus may produce the greatest displacement. It is not clear which is the optimal placement position. In addition, we look at the effect of the SS on sound transmission to the inner ear in ossicular reconstruction. METHODS: The ear-canal air pressure and vestibular hydro-pressure were measured in human cadaver temporal bones with incus intact, removed, and replaced with the MFP-ORP; the ORP head was placed at three different positions on the malleus (head, mid-manubrium, and umbo) while keeping its base at the center of stapes footplate with intact or removed stapes SS. The vestibular pressure ratio between the ear with intact incus and MFP-ORP reconstructed ear is defined as Lmfp, the loss caused by the prosthesis in relation to the normal ossicular chain. RESULTS: The mean magnitude of Lmfp, averaged in the important speech frequency region of 0.5 to 3 kHz, is approximately 7.8 dB at the neck with stapes SS. In comparison, mean magnitude of Lmfp for mid-manubrium without stapes SS is 15 dB (p = 0.04), and with the stapes SS it is 16 dB (p = 0.05), whereas at the umbo without SS it is 15 dB (p = 0.03). In the 8 kHz region, the mean magnitude of Lmfp is approximately 1 dB with the stapes SS intact and approximately 8.5 dB when it was removed (p < 0.09). CONCLUSION: There are significant physiologic advantages to placing the hydroxylapatite MFP-ORP beneath the neck of the malleus and preserving the SS. 相似文献
79.
LA Cox 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S406):84-85
A series of hand and wrist radiographs was assessed manually by two individuals and by a fully automated computer system for determining bone age. Assessments were repeated after 1 month to determine variability between and within the methods of bone age assessment. There was slight intra-observer variation, but complete reproducibility when assessments were made by computer. The variation between the human assessors was less than that between human and computer assessments. The difference between overall maturity scores made by the human observer and the computer system was, however, acceptably small, and the majority of assessments were the same. It is concluded this computer system for assessing bone age in normal children is reliable and accurate, but that it needs to be validated against a much larger set of radiographs. 相似文献
80.