Duodenal administration of solid lipid nanoparticles loaded with different percentages of tobramycin

Three types of solid lipid nanoparticles (SLN) containing three different percentages of tobramycin (1.25, 2.50, 5.00%) were prepared (Tobra-SLN), and the in vitro tobramycin diffusion through a hydrophilic/lipophilic membrane was determined. A variable quantity of each of the three SLN types was placed in the donor compartment to achieve the same amount of tobramycin in each case. Tobramycin diffusion varied with the percentage of drug incorporated in SLN: the higher the percentage of tobramycin incorporated, the greater the amount of the drug diffused. In vivo uptake and transport were determined after administering a fixed dose of tobramycin (5 mg/kg) in each of the three types of SLN intraduodenally to rats. At fixed times, blood was sampled from the jugular vein and lymph from the thoracic duct. Lymph and blood were examined by transmission electron microscopy (TEM) analysis to detect the presence, sizes, and shape of SLN. The pharmacokinetic parameters varied considerably with the type of Tobra-SLN: the area under the curve of plasma concentration versus time (AUC) of 1.25% Tobra-SLN was more than five times higher than that of 5.00% Tobra-SLN; the longest residence time was obtained with 1.25% Tobra-SLN; and the clearance of 5.00% Tobra-SLN was fivefold than that of 1.25% Tobra-SLN. This behavior may be related to the differences among the three types of SLN; namely, the number of SLN administered and the mean diameter, the total surface area, and the drug content in each nanoparticle. TEM analysis showed that Tobra-SLNs were targeted to the lymph. Tobra-SLN may act as a reservoir of the drug in the lymphatic system, thereby favoring its sustained release.     

29例筛窦癌的放射治疗

筛窦癌发病率低,就诊时病期晚,５年无瘤生存率为３０％～５０％。由于解剖部位的限制以及局部浸润,放射和手术均有一定难度。作者回顾性分析皇家Ｍａｒｇｒｅｔ医院１９７６～１９９４年收治的２９例浸润性筛窦癌根治性放射治疗的疗效和影响预后因素。男性２４例,女性４例,中位年龄６２岁,中位随访时间４年。常有鼻出血、鼻塞、疼痛及视力改变等。起病到确诊的平均时间为９个月。２７例吸烟,１０例从事伐木或镍的开采与提炼。　　治疗前均经临床及影像学检查。仅３例局限于筛窦,余侵犯鼻腔、蝶窦、眼眶、上颌窦、额窦及脑内等。Ｔ１…     

Epidermal cyst of the breast: Detection in a screening programme

Two cases of epidermal cyst of the breast, a rare benign condition, were detected during a 3-year period in a mammographic screening programme, from 57 954 screening examinations. It is not uncommon for epidermal cysts to be initially misdiagnosed. The mammographic, ultrasound and histological features are presented. It is recommended that these lesions be resected because they possibly have malignant potential.     

PRRT2-related disorders: further PKD and ICCA cases and review of the literature

Recent studies reported mutations in the gene encoding the proline-rich transmembrane protein 2 (PRRT2) to be causative for paroxysmal kinesigenic dyskinesia (PKD), PKD combined with infantile seizures (ICCA), and benign familial infantile seizures (BFIS). PRRT2 is a presynaptic protein which seems to play an important role in exocytosis and neurotransmitter release. PKD is the most common form of paroxysmal movement disorder characterized by recurrent brief involuntary hyperkinesias triggered by sudden movements. Here, we sequenced PRRT2 in 14 sporadic and 8 familial PKD and ICCA cases of Caucasian origin and identified three novel mutations (c.919C>T/p.Gln307*, c.388delG/p.Ala130Profs*46, c.884G>A/p.Arg295Gln) predicting two truncated proteins and one probably damaging point mutation. A review of all published cases is also included. PRRT2 mutations occur more frequently in familial forms of PRRT2-related syndromes (80–100 %) than in sporadic cases (33-46 %) suggesting further heterogeneity in the latter. PRRT2 mutations were rarely described in other forms of paroxysmal dyskinesias deviating from classical PKD, as we report here in one ICCA family without kinesigenic triggers. Mutations are exclusively found in two exons of the PRRT2 gene at a high rate across all syndromes and with one major mutation (c.649dupC) in a mutational hotspot of nine cytosines, which is responsible for 57 % of all cases in all phenotypes. We therefore propose that genetic analysis rapidly performed in early stages of the disease is highly cost-effective and can help to avoid further unnecessary diagnostic and therapeutic interventions.     

长鞭红景天化学成分的研究

长鞭红景天化学成分的研究彭江南，葛永潮，李晓晖（军事医学科学院放射医学研究所，北京１００８５０）红景天是滋补强壮药物，目前正引起人们极大的兴趣，现已有一些产品上市。我们曾对数种红景天的化学成分进行过研究［１～４］。长鞭红景天（Ｒｈｏｄｉｏｌａｆａｓｔ...     

Bile duct obstruction: radiologic evaluation of level, cause, and tumor resectability

In a prospective study of 65 patients with bile duct obstruction, various radiologic modalities were compared for their capability to demonstrate the level and cause of obstruction and to indicate accurately tumor resectability. Ultrasound (US) was performed in 65 patients, computed tomography (CT) in 51, direct cholangiography (DC) in 57, and angiography in 35. The level of obstruction was correctly indicated by US in 95% of patients and by CT in 90%, and the cause was correctly indicated by US in 88%, by CT in 63%, and by DC in 89%. In predicting tumor resectability, US was correct in 71% of patients, compared with 42% for CT, 58% for DC, and 25% for angiography. US therefore appears to be the single most useful modality in the evaluation bile duct obstruction.