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Mohsen?Vazirian Bijan?Nassirimanesh Saman?ZamaniEmail author Masako?Ono-Kihara Masahiro?Kihara Shahrzad?Mortazavi Ravari Mohammad?Mehdi?Gouya 《Harm reduction journal》2005,2(1):19
HIV infection rates have reached epidemic proportions amongst injecting drug users (IDUs) in Iran. Although a number of community-based
interventions have being implemented in the country, there is little information on the risk behaviors of IDU participants
in these programs. This cross-sectional report aimed to compare the risk behaviors of injecting drug users with differential
exposure rates to an HIV outreach program in Tehran, Iran. Results indicated that shared use of needle/syringe in the past
month was significantly lower among IDUs who received estimated ≥ 7 syringes per week than those who did not [adjusted odds
ratio (OR) = 14.36, 95% confidence interval (CI) 2.30–89.56]. While the effectiveness of this outreach program needs further
evaluation through a longitudinal investigation, our preliminary findings suggest that the outreach program in Tehran may
have been beneficial in reducing direct sharing among those who received more than several needles/syringes from the program. 相似文献
994.
Oishi M Maeda S Nakamura A Kurokawa N Ohguro N Tano Y 《Japanese journal of ophthalmology》2005,49(5):384-387
Purpose
Intravitreal injection of triamcinolone acetonide (TA) is used in ophthalmic treatment, but the reliability of commercially available TA preparations has still not been established. We evaluated two previously reported purification methods, and developed a more reliable TA injection which can be prepared in a hospital pharmacy.Methods
We tested the two methods previously reported for purifying commercial TA preparations, the sedimentation and the filtration and backflushing methods. We developed a new TA injection made of pure TA suspended in 0.5% sodium hyaluronate. We measured the TA content in each preparation by high-performance liquid chromatography to evaluate the three methods.Results
In the sedimentation purification method, the TA content of a nominal 4-mg preparation varied from 1.43 to 7.37?mg, and the average recovery rate was 91.6%. In the filtration and backflushing method, TA content was 0.10–10.33?mg and recovery was 59.5%. In the TA injection we developed, the mean TA content was 102.5% (SD, 0.24; CV, 2.9%). The stability of this preparation was 99% after sterilization, and 97% after 3 months of storage.Conclusions
The results of our investigation showed that the purification methods used for commercial preparations are simple and easy but not precise enough for an intravitreal injection. In contrast, the TA injection prepared by our method is reliable, stable, and safe enough for clinical use. Jpn J Ophthalmol 2005;49:384–387 © Japanese Ophthalmological Society 2005 相似文献995.
Ishikawa K Terasaki H Mori M Sugita K Miyake Y 《Japanese journal of ophthalmology》2005,49(5):411-413
Background
The pathogenesis of optic disc pit maculopathy is still unknown, although recent optical coherence tomographic (OCT) analyses have made a great contribution to clarifying its morphological appearance. The best treatment for this disease is also controversial.Case
We report on a 7-year-old girl with optic disc pit maculopathy associated with a separation of the internal limiting membrane (ILM) near the optic disc.Observations
The OCT images before treatment showed a conduit from the perineural space to the schisislike separation of the sensory retina with a dome-shaped separation of the ILM. A serous detachment (SD) in the macula, centered on the fovea, was also present. In OCT images after laser photocoagulation, the conduit appeared to be closed, but the SD was still present. Vitrectomy with ILM removal and gas tamponade resulted in a marked reduction of the SD in the macular area. Focal macular electroretinograms and visual acuity demonstrated a recovery of macular function.Conclusion
The dome-shaped separation of the ILM suggested that the vitreous might be exerting a tractional force on the optic disc pit, and vitrectomy with ILM peeling released the traction on the optic disc pit. Jpn J Ophthalmol 2005;49:411–413 © Japanese Ophthalmological Society 2005 相似文献996.
997.
Katsuyama M Masako K Ichikawa H Hideyuki I Ogawa S Shigeyuki O Ikezawa Z Zenro I 《Journal of dermatological science》2005,38(3):197-205
BACKGROUND: Staphylococcus aureus (SA) is usually present in atopic dry skin, and not only in regions seriously affected by atopic dermatitis. SA discharges various toxins and enzymes that injure the skin, and forms a biofilm from fibrin fiber and glycocalyx; the biofilm is important for adhesion of SA to the skin and for resistance to anti-microbial agents. Even highly effective moisturizers do not work perfectly on atopic dry skin. Staphylococcus epidermidis (SE) is a major constituent of skin microflora on healthy human skin, and provides protection against the growth of pathogenic bacteria. OBJECTIVES: Since treatment with anti-microbials may lead to re-growth of SA, which grows faster than other Staphylococci and often shows antibiotic resistance, we searched for novel approaches to control the skin-microfloral balance without using conventional anti-microbials. METHOD: Biofilm formation by SA in vitro was observed in detail using scanning electron microscopy. Approximately 500 substances were screened for a selective effect on SA growth and SA biofilm. RESULTS: We found that xylitol inhibited the formation of glycocalyx, and farnesol dissolved fibrin fibers. Farnesol suppressed the growth of only SA, and did not affect that of SE. Xylitol and farnesol synergistically inhibited biofilm formation by SA. CONCLUSION: Xylitol and farnesol have potential for controlling the skin-microfloral balance because of their selective effects and inhibition of biofilm formation. They might provide a useful and safe method to care for skin colonized by SA, without using antibiotics. 相似文献
998.
Kato S Kato M Abe Y Matsumura T Nishino T Aoki M Itoyama Y Asayama K Awaya A Hirano A Ohama E 《Acta neuropathologica》2005,110(2):101-112
Peroxiredoxin-ll (Prxll) and glutathione peroxidase-l (GPxl) are regulators of the redox system that is one of the most crucial supporting systems in neurons. This system is an antioxidant enzyme defense system and is synchronously linked to other important cell supporting systems. To clarify the common self-survival mechanism of the residual motor neurons affected by amyotrophic lateral sclerosis (ALS), we examined motor neurons from 40 patients with sporadic ALS (SALS) and 5 patients with superoxide dismutase 1 (SOD1)-mutated familial ALS (FALS) from two different families (frame-shift 126 mutation and A4 V) as well as four different strains of the SOD1-mutated ALS models (H46R/G93A rats and G1H/G1L-G93A mice). We investigated the immunohistochemical expression of Prxll/GPxl in motor neurons from the viewpoint of the redox system. In normal subjects, Prxll/GPxl immunoreactivity in the anterior horns of the normal spinal cords of humans, rats and mice was primarily identified in the neurons: cytoplasmic staining was observed in almost all of the motor neurons. Histologically, the number of spinal motor neurons in ALS decreased with disease progression. Immunohistochemically, the number of neurons negative for Prxll/GPxl increased with ALS disease progression. Some residual motor neurons coexpressing Prxll/GPxl were, however, observed throughout the clinical courses in some cases of SALS patients, SOD1-mutated FALS patients, and ALS animal models. In particular, motor neurons overexpressing Prxll/GPxl, i.e., neurons showing redox system up-regulation, were commonly evident during the clinical courses in ALS. For patients with SALS, motor neurons overexpressing Prxll/GPxl were present mainly within approximately 3 years after disease onset, and these overexpressing neurons thereafter decreased in number dramatically as the disease progressed. For SOD1-mutated FALS patients, like in SALS patients, certain residual motor neurons without inclusions also overexpressed Prxll/GPxl in the short-term-surviving FALS patients. In the ALS animal models, as in the human diseases, certain residual motor neurons showed overexpression of Prxll/GPxl during their clinical courses. At the terminal stage of ALS, however, a disruption of this common Prxll/GPxl-overexpression mechanism in neurons was observed. These findings lead us to the conclusion that the residual ALS neurons showing redox system up-regulation would be less susceptible to ALS stress and protect themselves from ALS neuronal death, whereas the breakdown of this redox system at the advanced disease stage accelerates neuronal degeneration and/or the process of neuronal death. 相似文献
999.
Effect of remnant-like particle on shear-induced platelet activation and its inhibition by antiplatelet agents 总被引:2,自引:0,他引:2
Remnant-like particles (RLPs) have been reported to promote atherosclerosis and to have effects on platelet function. We studied the effects of RLP on shear-induced platelet activation and their inhibition by antiplatelet agents in vitro. RLP were separated using two monoclonal antibodies, anti apo B-100 and anti apo A-I. These RLP fractions were added to whole blood (WB) or platelet-rich plasma (PRP) in serial dilution of 1, 10 or 100 microg RLP triglyceride (TG) per ml of total sample volume. These samples were incubated, and then stimulated with a high shear stress of 108 dyn/cm(2). Shear-induced platelet aggregation (SIPA) was calculated from the percentage of single platelet loss. P-selectin expression on platelet surface and platelet-derived microparticle (PMP) generation were measured before and after stimulation with shear stress using flow cytometer. SIPA was significantly enhanced by RLP in WB but not in PRP. This enhancing effect was not dose-dependent and was greatest at 10 microg TG/ml. P-selectin expression induced by shear stress was only enhanced by RLP at a concentration of 100 microg TG/ml in both WB and PRP, while generation of PMP induced by shear stress was only enhanced by RLP at a concentration of 100 microg TG/ml in WB. Aspirin inhibited only the enhancement of SIPA by RLPs, while cilostazol inhibited the enhancement of not only SIPA but also p-selectin expression and PMP generation by RLPs. 相似文献
1000.
It is important to create a link between stereotaxic coordinates and head-surface-based positioning systems in order to share data between tomographic and transcranial brain mapping studies. In our previous studies, we established the probabilistic correspondence of the international 10-20 positions to the standard stereotaxic coordinate systems and made a reference database. However, its expansion required the physical marking of the 10-20 positions and the subsequent acquisition of MR images. To avoid such tedious procedures, we developed a virtual 10-20 measurement algorithm that can be applied to re-analyze any structural MR image that covers the whole head. As in the physical 10-20 measurements, with the reference points given, the algorithm automatically determines each 10-20 position step by step. Using the virtual 10-20 measurement method, we re-analyzed the MR images of 17 healthy subjects for whom we had determined 10-20 positions by physical marking in our previous study. The acquired 10-20 positions were normalized to the Montreal Neurological Institute (MNI) stereotactic coordinates and compared with the positions previously determined by physical measurements. 10-20 positions determined using the virtual and physical methods were roughly consistent. Average standard deviations for virtual and physical methods were 7.7 mm and 9.0 mm, respectively. There was a systematic shift in the virtual method, likely due to the absence of hair interference. We corrected the shift with affine transformation. The virtual 10-20 measurement method proved to be an effective alternative to physical marking. This method will serve as an essential tool for expanding the reference database and will further strengthen the link between tomographic and transcranial brain mapping methods. 相似文献