Structure-Skin Permeability Relationship of Dendrimers

Purpose  

To investigate skin penetration of poly (amidoamine) (PAMAM) dendrimers as a function of surface charge and molecular weight in presence and absence of iontophoresis.     

2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine increases the numbers of tumors, cystic crypts and aberrant crypt foci in multiple intestinal neoplasia mice

The multiple intestinal neoplasia (Min) mice have a mutation in the murine adenomatous polyposis coli (Apc) gene rendering them highly susceptible to spontaneous intestinal adenoma formation, similar to the familial adenomatous polyposis (FAP) syndrome in humans. We studied whether the most abundant mutagenic heterocyclic amine isolated from cooked food, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), could influence early intestinal neoplasia in C57BL/6J-Min/+ and C57BL/6J- +/+ (wild-type) mice of both sexes. PhIP was given in 4 weekly i.p. injections of 50 mg/kg. Ten weeks after the start of the experiment, PhIP had significantly increased the numbers of small tumors and cystic crypts in the proximal section of the small intestine in male Min/+ mice, and the numbers of aberrant crypt foci (ACF) in the large intestines of both males and females. The effects of PhIP were more pronounced in male than in female Min/+ mice. In +/+ mice, no tumors or cystic crypts in the small intestine, and no tumors and only a very few ACF in the large intestine, were induced by PhIP. These results show that a substance frequently present in the human diet is able to enhance the neoplastic process induced by a genetic lesion, which is also commonly found both in inherited and sporadic colon carcinomas in humans.      

男性迟发性性腺功能减退症的检查、治疗和监测:国际男科学会(ISA)、国际老年男性研究会(ISSAM)、欧洲泌尿外科学会(EAU)、欧洲泌尿外科学院(EAA)和美国男科学会(ASA)联合推荐

简介 人口学资料明确显示:老年人口占总人口的百分率正逐年增加.当前,有关老年男性雄激素缺乏的问题逐渐成为令人感兴趣、但又充满争议的世界性话题.已经有横向和纵向的研究资料表明,随着年龄增大,成年男子的雄激素水平逐渐降低,且相当一部分年龄超过60岁男性的血清睾酮水平已降到正常年轻成年男性(20～30岁)的低限值以下.     

Temporal development of baroreceptor dysfunction in a rodent model of chronic kidney disease

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Cardiovascular autonomic dysfunction in a novel rodent model of polycystic kidney disease

Autonomic dysfunction, hypertension and cardiovascular morbidity in end stage renal disease are critically linked, however there are limited models available to investigate this relationship and develop clinical interventions. This study aimed to define the relationship between hypertension and autonomic function in a new rodent model of polycystic kidney disease (PKD). Using measures of heart rate and systolic blood pressure variability (HRV, SBPV), and time domain analysis of cardiac and sympathetic baroreflex function, we compared the Lewis PKD model (LPK) to a Lewis control. Systolic BP and SBPV were significantly higher in LPK vs. Lewis (168 ± 7 vs. 131 ± 8 mm Hg, P ≤ 0.01, total power: 11 ± 3.1 vs. 1.3 ± 0.3 mm Hg/Hz², P ≤ 0.05). LPK has a higher resting HR (437 ± 17 vs. 330 ± 11 beats per minute [bpm], P ≤ 0.001) associated with reduced HRV (total power [1.7 ± 0.3 vs. 4.6 ± 1.1 ms/Hz², P ≤ 0.01]). Atenolol decreased HR to a greater extent in the LPK (90 ± 10 vs. 20 ± 17 bpm, P ≤ 0.001) while subsequent methylatropine administration produced a greater increase in Lewis HR (24 ± 9 vs. 66 ± 9 bpm, P ≤ 0.01). No difference in intrinsic HR following both drugs existed. Cardiac baroreflex function was impaired in LPK vs. Lewis (0.6 ± 0.4 vs. 1.2 ± 0.2 bpm/mm Hg P ≤ 0.05, and 0.3 ± 0.1 vs. 3.1 ± 0.6 ms/mm Hg, P ≤ 0.001, respectively). The sympathetic baroreflex function curve was shifted upwards and towards the right in LPK (P ≤ 0.01). Sympathetic baroreflex gain was not altered. This data suggests that sympathetic hyperactivity and reduced vagal function underlies the hypertension and reduced cardiac baroreflex function in the LPK model.     

Average fetal depth in utero: data for estimation of fetal absorbed radiation dose

To estimate fetal absorbed dose from radiographic examinations, the depth from the anterior maternal surface to the midline of the fetal skull and abdomen was measured by ultrasound in 97 pregnant women. The relationships between fetal depth, fetal presentation, and maternal parameters of height, weight, anteroposterior (AP) thickness, gestational age, placental location, and bladder volume were analyzed. Maternal AP thickness (MAP) can be estimated from gestational age, maternal height, and maternal weight. Fetal midskull and abdominal depths were nearly equal. Fetal depth normalized to MAP was independent or nearly independent of maternal parameters and fetal presentation. These data enable a reasonable estimation of absorbed dose to fetal brain, abdomen, and whole body.     

Transducer frequency considerations in intraoperative US of the spine

To determine the effect of transducer frequency, we used intraoperative spinal ultrasound to study 15 patients. All patients but one had spinal stenosis and/or disk disease affecting the cervical cord (n = 5), the thoracic cord (n = 1), or the lumbosacral area (n = 8). One patient had an arteriovenous malformation of the cervical cord. Both 5-MHz and 10-MHz transducers were used in one patient; a transducer with the option of 3.5, 5, or 7.5 MHz was used in ten; and a 10-MHz transducer was used in four. We found that, intraoperatively, 10-MHz transducers currently produce the most detailed images of the spine.