Development of the biologically active Guglielmi detachable coil for the treatment of cerebral aneurysms. Part II: an experimental study in a swine aneurysm model

BACKGROUND AND PURPOSE: Ion implantation is a surface-modification technology that creates a borderless surface on protein-coated platinum; this change in physical and chemical properties on the surface of Guglielmi detachable coils (GDCs) appears to enhance cell proliferation and adhesion. Our purpose was to evaluate the effect of ion implantation on GDCs in an experimental aneurysm model. METHODS: GDCs were coated with either type I collagen, fibronectin, vitronectin, laminin, or fibrinogen. Using He+ or Ne+ 1 x 10(14-15) ions/cm2, ion implantation was performed on these protein-coated GDCs (GDC-Is). A total of 56 experimental aneurysms were constructed microsurgically in the common carotid arteries of 28 swine. These experimental aneurysms were embolized with standard GDCs (n = 23), collagen GDC-Is (n = 11), vitronectin GDC-Is (n = 6), laminin GDC-Is (n = 4), fibrinogen GDC-Is (n = 6), and fibronectin GDC-Is (n = 6). The animals were sacrificed at day 14 after coil embolization. The physical properties of the new coils (friction on delivery, deployment into aneurysms, trackability, etc) and the development of tissue scarring and neoendothelium across the aneurysm's orifice were evaluated macroscopically and microscopically. RESULTS: No evidence of increased coil friction/stiffness was observed during delivery of GDC-Is through microcatheters in this aneurysm model. A more intense scar formation and neoendothelium at the neck of aneurysms were observed macroscopically when treated with GDC-Is. Significant differences in the proportion of neck coverage between standard GDCs (48.3% +/- 20.5%) and all GDC-I groups were observed (collagen GDC-I-89.4% +/- 14.9%, P < .01; vitronectin GDC-I-71.5% +/- 7.0%, P < .05; laminin GDC-I-76.5% +/- 11.0%, P < .05; fibrinogen GDC-I-74.8% +/- 13.9%, P < .05; fibronectin GDC-I-87.5% +/- 15.0%, P < .01). Light microscopy showed a well-organized fibrous tissue bridging the aneurysm's neck when using GDC-Is, whereas only a fibrin-like thin layer covered the standard GDC surfaces. CONCLUSION: GDC-Is indicated a more intense inflammatory response in the aneurysm body and dome and faster re-endothelial coverage of the neck of the aneurysm. This accelerated histologic response may decrease the chances of coil compaction and aneurysm recanalization. This technology may improve anatomic and clinical outcomes in patients harboring intracranial aneurysms.     

Binaural advantage on usage of hearing aid together with cochlear implant--examination on speech perception (Japanese monosyllable word list 67-S and Japanese HINT)]

Six cochlear implant recipients with hearing aids in the opposite ear were studied to survey binaural advantage. They were examined in separate tests by using a hearing aid alone, cochlear implant alone, and by using both devices (bimodal condition). Test items used were the Japanese monosyllable word list 67--S and Japanese HINT. Statistically significantly results were obtained in the bimodal condition, three out of six subjects were successful in the monosyllable word test and all successful in the Japanese HINT. We conclude that all subjects enjoyed binaural advantage in speech perception in bimodal condition with no conflict at the recognition level; even when different sounds from cochlear implant and contralateral hearing aid were received. The plasticity of the brain is thought to be of importance in the bimodal condition.     

Poison elimination methods in acute poisoning

This paper presents current ideas about the application of poison elimination methods in acute poisoning. The methods are divided into two groups: poison elimination before absorption; and enhancement of elimination after drug absorption. The former include washes, emesis, gastric lavage, and administration of activated charcoal and cathartics, while the latter include forced diuresis and extracorporeal toxin elimination such as hemodialysis or hemoperfusion. The indications, contraindications, techniques, and complications, associated with these elimination methods, except for extracorporeal toxin elimination, are discussed. In the treatment of poisoning, early and comprehensive poison elimination is important.     

Accumulation of class I mutant p53 and apoptosis induced by carboplatin in a human glioma cell line

Following DNA damage, wild-type p53 increases and mediates the multiple cellular responses for the repair of DNA damage or apoptosis. Inactivation of p53 by single-amino-acid substitutions contributes to the malignant phenotype and confers resistance to therapy. Among tumor-derived p53 mutants, class I mutants still retain a native-like three-dimensional structure, whereas class II mutants have unfolded DNA-binding domains. Sequencing analysis demonstrated that a human glioma cell line (U-373MG) had only a class I mutant form of p53 of His273, which targets an Arg273 that contacts DNA but retains the native structure. In this study, we investigated the metabolic alteration of the class I mutant p53 in apoptosis of U-373MG. The cell cycle progression of U-373MG cells was affected by the addition of carboplatin, while the amount of mutant p53 also increased in their nuclei. The treated cells underwent apoptosis 48h after exposure to 50 μg/ml carboplatin. Although the exact mechanism of the class I mutant p53 in the process of apoptosis has not yet been clarified, the fact that accumulation of the activated mutant p53 in the nucleus of U-373MG is concomitant with apoptosis, just as wild-type p53 does, implies that the class I mutant p53 might retain the ability to participate in apoptosis.     

Unexpected difficult intubation caused by a laryngeal web

We report a case of unexpected difficult intubation in an adult caused by a laryngeal web. A 43-year-old woman with uterine myoma was scheduled for abdominal hysterectomy. After induction of anesthesia, the vocal cords were seen clearly under laryngoscopy. Although intubation was attempted several times, a 6.5 mm internal diameter tracheal tube could not be passed below the level of the vocal cords because of resistance, and we used a laryngeal mask during anesthesia. Next morning after the operation, she developed dyspnea. Bronchoscopy revealed a very narrow airway below the level of vocal cords caused by a laryngeal web. Tracheostomy was performed. Two weeks later, tracheostomy was closed without any sequela.     

Sex and Cultural Differences in Spatial Performance Between Japanese and North Americans

Previous studies have suggested that Asians perform better than North Americans on spatial tasks but show smaller sex differences. In this study, we evaluated the relationship between long-term experience with a pictorial written language and spatial performance. It was hypothesized that native Japanese Kanji (a complex pictorial written language) educated adults would show smaller sex differences on spatial tasks than Japanese Americans or North Americans without Kanji education. A total of 80 young healthy participants (20 native Japanese speakers, 20 Japanese Americans-non Japanese speaking, and 40 North Americans-non Japanese speaking) completed the Rey Complex Figure Test (RCFT), the Mental Rotations Test (MRT), and customized 2D and 3D spatial object location memory tests. As predicted, main effects revealed men performed better on the MRT and RCFT and women performed better on the spatial object location memory tests. Also, as predicted, native Japanese performed better on all tests than the other groups. In contrast to the other groups, native Japanese showed a decreased magnitude of sex differences on aspects of the RCFT (immediate and delayed recall) and no significant sex difference on the efficiency of the strategy used to copy and encode the RCFT figure. This study lends support to the idea that intensive experience over time with a pictorial written language (i.e., Japanese Kanji) may contribute to increased spatial performance on some spatial tasks as well as diminish sex differences in performance on tasks that most resemble Kanji.