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71.
Adult patients with Down syndrome show psychological symptoms and early senility. Improving their environment and dealing with their complaints and stress should first address their behavioral problems, such as self-injury, depression, aggression and outbursts. Pharmacological treatment may also be tried for behavioral disorders. Individuals with Down syndrome demonstrate neurotransmitter changes such as the loss of acetylcholine, norepinephrine, and serotonin (5-HT) with increasing age. Selective serotonin re-uptake inhibitor (SSRI) is effective for depression and panic disorders. We report here the effect of SSRI in two adult male patients with Down syndrome, 35 and 47 years of age. Self-injury in one case and aggression and outbursts in another improved after 1 week of fluvoxamine treatment, suggesting the effects of SSRI for behavioral disorders of adult Down syndrome. 相似文献
72.
System-engineered cartilage using poly(N-isopropylacrylamide)-grafted gelatin as in situ-formable scaffold: in vivo performance 总被引:6,自引:0,他引:6
Our previous study showed that cartilaginous tissue can be engineered in vitro with articular chondrocytes and poly(N-isopropylacrylamide)-grafted gelatin. This short-term in vivo study for cartilage repair was performed to screen a candidate method for a long-term study. In our previous in vitro study, however, two potential problems with the tissue-engineered cartilage were identified: (1). leakage of the transplant due to temperature decline and (2). concave deformation of transplant due to compressive loading. To solve these problems, we investigated in this study the usefulness of suturing with two different covering materials (periosteum or collagen film) and preculturing an engineered tissue for 2 weeks. PNIPAAm-gelatin-based engineered cartilage samples were evaluated at 5 weeks after operation by gross and microscopic examination. Leakage occurred only in specimens without precultured tissue and with a collagen film. Minimal surface deformation occurred in all specimens with precultured tissue. The score on gross examination showed that transplants with precultured tissue acquired a higher score than did the others. Histological evaluation showed a minimal foreign-body response of PNIPAAm-gelatin in all specimens and higher maturity as a cartilaginous tissue in specimens with precultured tissue. These results indicate that transplantation with precultured tissue may be a suitable method for a long-term in vivo study. 相似文献
73.
Nakayama Y Nishi S Ueda-Ishibashi H Matsuda T 《Journal of biomedical materials research. Part A》2003,64(1):52-61
To prevent thrombus formation in the acute phase and restenosis in the subacute to chronic phase after stenting of atherosclerotic arteries, we developed a covered stent with a micropored elastomeric film, the blood-contacting surface of which was coated with a photocured gelatin layer immobilized with heparin. Segmented polyurethane (SPU) film (30 microm in wall thickness) as a cover material was multiply micropored by excimer laser-directed microprocessing (pore diameter, 30 microm; interpore distance, 125 microm). An aqueous mixed solution of benzophenone-derivatized gelatin and heparin was coated on the micropored SPU film. Upon ultraviolet light irradiation, a thin layer of a gelatin gel immobilized with heparin was formed and simultaneously fixed on the SPU film. The fully covered stents were assembled by wrapping a balloon-expandable stent with gelatin/heparin gel-layered SPU film and subsequently suturing and then gluing. To assess the validity of this covered stent in vivo, "half-covered" stents, in which half at the distal side was covered with the gel-layered SPU film, was implanted in rabbit common carotid arteries (about 3 mm in diameter). After 3 months of implantation, all the half-covered stents (n = 7) were patent. Regardless of the covered or noncovered region of the stents, the entire luminal surface of the stents was fully endothelialized and a thin neointimal tissue was formed. The potential advantages of a covered stent as designed above are discussed. 相似文献
74.
Brodbeck WG Voskerician G Ziats NP Nakayama Y Matsuda T Anderson JM 《Journal of biomedical materials research. Part A》2003,64(2):320-329
An in vivo mouse cage implant system was used to determine whether leukocyte cytokine mRNA responses to implanted biomaterials were dependent on surface chemistry. Surfaces displaying various chemistries (hydrophobic, hydrophilic, anionic, and cationic) were placed into stainless steel cages and implanted subcutaneously. Semiquantitative RT-PCR analyses revealed that hydrophilic surfaces showed a decreased expression of proinflammatory cytokines, IL-6 and IL-8, and pro-wound healing cytokines, IL-10 and TGF-beta by adherent cells, and mRNA levels of the proinflammatory cytokine, IL-1beta, and the pro-wound healing cytokine IL-13 were decreased in surrounding, exudate cells. Cytokine responses by adherent and exudate cells to hydrophobic, anionic and cationic surfaces were similar and indicative of a strong inflammatory response at the earliest time point followed by a wound healing response at later time points. However, no differences in the types or levels of exudate cells for any of the surfaces or the empty cage at each of the respective time points were observed, indicating their respective biocompatibility. These studies identify hydrophilic surface chemistries as having significant effects on leukocyte cytokine responses in vivo by decreasing the expression of inflammatory and wound healing cytokines by inflammatory cells adherent to the biomaterial as well as present in the surrounding exudate. 相似文献
75.
Ndembi N Habakkuk Y Takehisa J Takemura T Kobayashi E Ngansop C Songok E Miura T Ido E Hayami M Kaptue L Ichimura H 《AIDS research and human retroviruses》2003,19(5):435-439
To investigate the route of zoonotic transmission of HIV-1, we isolated three and seven HIV-1 strains from 449 Pygmy hunter gatherers and 169 neighboring Bantu, respectively, in southern Cameroon. Phylogenetic analysis based on pol-integrase and env-C2V3 sequences revealed that strains from Pygmies were 1CRF02_AG/CRF02_AG, 1 subtype G/CRF02 AG (pol/env), and 1 CRFll_cpx/CRF11_cpx, and that those from Bantu were 2 CRF02_AG/CRF02_AG, 1 CRF02_AG/CRF01_AE/A, 1 CRF02_AG/subtype A, 1 G/A, 1G/CRF02_AG, and 1 unclassified fH. CRF02_AG and CRF11_cpx have been identified in Cameroon. The results suggest that HIV-1 has been introduced into Pygmies through their neighboring Bantu rather than directly from nonhuman primates. 相似文献
76.
OBJECTIVE: An embolization technique using a stent graft has been developed to replace the conventional type of direct surgery or neurointervention with platinum coils and/or bare stents. The utility of a commercially available metal stent wrapped with a microporous elastomeric film coated with a thin, heparin-loaded, photocured gelatinous layer for the treatment of experimental carotid artery sidewall aneurysms in dogs was evaluated. METHODS: The stent graft was used for embolization of experimental carotid artery aneurysms in dogs. The aneurysms were prepared bilaterally in canine carotid arteries with branching of an external jugular vein patch. RESULTS: The entries into all of the aneurysms were occluded immediately after placement of the stent grafts, and the aneurysms were embolized by thrombus formation even 1 week after deployment. All of the parent carotid arteries in which stent grafts were placed were patent, without severe stenosis, immediately (n = 2), 1 week (n = 4), 1 month (n = 3), and 3 months (n = 4) after placement. Scanning electron microscopy demonstrated that the luminal surfaces of the stent grafts were entirely endothelialized as soon as 1 week after placement, via transmural tissue ingrowth through the micropores formed in the covering film. CONCLUSION: The stent graft we have developed seems to be highly promising for the treatment of aneurysms, especially with respect to immediate termination of blood inflow for aneurysm occlusion and rapid endothelialization in the aneurysm neck. 相似文献
77.
OBJECTIVE: The association of ventricular diverticula with intra- and paraventricular tumors causing obstructive hydrocephalus has rarely been reported. METHODS: Records and imaging findings for 57 patients with obstructive hydrocephalus caused by tumors who were treated at our institution were reviewed for the presence of ventricular diverticula. For the anatomic study of ventricular diverticula, data were collected from five cadaveric heads. RESULTS: Ventricular diverticula were identified on magnetic resonance imaging scans in five cases. Diverticula were similarly located in the quadrigeminal cistern but originated from the medial wall of the atrium of the lateral ventricle in three cases and from the superior portion of the fourth ventricle in two cases. Regression of diverticula occurred in all cases after either insertion of a shunt or removal of the obstructing tumor. The cadaveric study suggested that the choroidal fissure and the rostral portion of the superior medullary velum might be the origins of diverticula from the atrium and from the superior portion of the fourth ventricle, respectively. CONCLUSION: Ventricular diverticula should be distinguished from other cystic lesions in the quadrigeminal region. Detection of an ostium of a diverticulum or communication between the cyst and the ventricular system is important for diagnosis. 相似文献
78.
Inferior temporal sulcus approach for amygdalohippocampectomy guided by a laser beam of stereotactic navigator 总被引:8,自引:0,他引:8
Miyagi Y Shima F Ishido K Araki T Taniwaki Y Okamoto I Kamikaseda K 《Neurosurgery》2003,52(5):1117-23; discussion 1123-4
OBJECTIVE: To describe a surgical technique for a minimally invasive transcortical transventricular amygdalohippocampectomy via the inferior temporal sulcus (ITS) using a stereotactic navigator. METHODS: Seven patients with medically intractable mesial temporal lobe epilepsy underwent an amygdalohippocampectomy via the ITS. By use of a laser-guided navigation system, the epileptogenic foci of the mesial temporal lobe were resected through a small linear operative route that was made by a brain speculum inserted from the ITS to the anterolateral floor of the temporal horn in the lateral ventricle. RESULTS: All patients completed at least a 1-year follow-up (range, 14-45 mo) after surgery and had improved neuropsychological parameters as a result of the operation. All patients became seizure-free after surgery. A Humphrey visual field perimeter detected no hemianopsia. CONCLUSION: Combined with the stereotactic navigation system, the ITS approach provides the least invasive amygdalohippocampectomy that preserves optic radiation. This approach seems beneficial especially in patients in whom the epileptic lesions are limited to the anterior mesial temporal lobe. 相似文献
79.
80.
Purpose. We conducted this study to find out whether the peak-to-peak pulsatility index (PPI) predicted graft failure and which factors affected the PPI.Methods. Color-duplex sonography was used to take 520 scans of 74 infrainguinal bypasses, 62 of which were femoropopliteal bypasses and 12 of which were femorocrural bypasses. Vessel diameter and velocity waveform were measured in the graft as well as in the proximal and distal arteries.Results. There were 13 cases of graft failure. The PPI in the mid-graft was significantly different in the normal group (12.30 ± 8.77) and the graft failure group (4.17 ± 1.79). A PPI of less than 7.0 in the mid-graft was defined as graft failure, with a sensitivity of 96.0% and a specificity of 77.6%. There was no correlation between the graft diameter and the PPI. The average mode frequency was inversely correlated with the PPI (PPI = 44.8 × Mode F–1 + 3.50, correlation co-efficient: 0.78).Conclusion. One point measurement of the PPI in the mid-graft could be a simple and useful parameter for diagnosing graft failure, based on our finding that the waveform was very similar in the proximal artery, the entire graft, and the distal artery. PPI was inversely correlated with average mode frequency because reverse flow decreased or diminished when a significant stenosis existed. 相似文献