124 research outputs found
The Divalent Titanium Complex Ti(O-i-Pr)4/2i-PrMgX as an Efficient and Practical Reagent for Fine Chemical Synthesis
New efficient and sophisticated reagents and reac-tions for organic synthesis are being developed more and more rapidly each year. Owing to these develop-ments, modern organic synthesis has reached such
Stereoselective Synthesis of a-Branched Amines Based on Formation of Azatitanacyclic Compounds
本研究では, 当初の目的に従って,(η2-イミン)チタン錯体の発生とこれを基盤とするα-分岐アミン類の効率よい合成法開発として,4-1. アザチタナシクロペンタンの生成と新電子剤との反応によるpyrrolidine のone-pot 合成法開発 4-2. アザチタナシクロプロパンとプロパルギル化合物との反応による2-置換pyrrole および3-pyrroline の合成法開発 4-3. イミンの還元的カップリングによる1,2-ジアミンの合成法開発 について検討し,α-分岐構造を含むピロリヂン類の立体選択的な合成法を開発した。また,その途上で2-置換ピロール類のアルデヒド,アミンからのone-pot 合成法を開発した。さらに,(η2-イミン)チタン錯体を経由する簡便な1,2-ジアミンのdl 選択的な合成法を確立した。さらに,2価チタンを発生するTi(O-i-Pr)4/2i-PrMgX 反応剤の問題点を解決する目的で検討したところ,Ti(O-i-Pr)4/TMSCl/Mg 反応剤が新しい低原子価チタン反応剤となる事を見いだした。加えて,これら反応検討に関連して,CaH2/ZnX2/Ti(O-i-Pr)4 反応剤を見いだし,反応性が低いCaH2 を初めて有機化合物の直接的な還元剤として利用する事に成功した。 4-4. CaH2/ZnX2/Ti(O-i-Pr)4 反応剤の開発とイミンの還元によるα-分岐アミンの合成法2価のチタン反応剤を用いるヘテロ環状化合物の合成法として検討した,直鎖の不飽和化合物の環化反応が効率よく進行することを見いだした。この反応は,主にステロイド C,D 環部の立体選択的な構築法の開発へ展開した。 4-5. Ti(II)-環化法による炭素およびヘテロビシクロ骨格の構築法平成16年度~平成17年度 科学研究費補助金(基盤研究(C) )(研究課題番号:16550102
A New Method for the Synthesis of Protected Chiral 4-Hydroxy-2-cyclopentenone
A new method for the synthesis of (R)-4-t-butyldimethylsiloxy-2-cyclopentenone (1, R = t-BuMe2-Si) has been developed which involves the effective preparation of the chiral (Z)-γ-iodo allylic alcohol and its conversion into 1 via cycliacylation reaction
Synthesis of Allyl Ester of Prostaglandin E and the Conversion of the Allyl Ester Moiety into Carboxylic Acid by Chemical Method. A Highly Practical Synthesis of Natural PGE1 and Limaprost
Synthesis of prostaglandin E allyl ester via two-component coupling process and the conversion of the allyl ester moiety into free carboxylic acid by the reaction with HCO2H-Et3N in the presence of a palladium catalyst has been described
A multicenter survey for submacular hemorrhage
Purpose
To evaluate the clinical characteristics, treatment trends, and visual prognosis of submacular hemorrhage (SMH) secondary to neovascular age-related macular degeneration (nAMD) and retinal arterial macroaneurysm (RAM).
Methods
This retrospective study enrolled 187 Japanese patients with SMH at 10 institutions from 2015 to 2018. Medical records including SMH etiology, best-corrected visual acuity (BCVA), fundus photographs, optical coherence tomography images, and selected treatments were analyzed.
Results
Major causes of SMH were typical nAMD (tnAMD) (18%), polypoidal choroidal vasculopathy (PCV) (50%) and RAM (29%). Age, male/female ratio, baseline BCVA, central retinal thickness, and involved retinal layers were significantly different between etiologies (all P<0.0001). Treatment with anti-vascular endothelial growth factor drugs with and without intravitreal gas injection was chosen for half of eyes in the tnAMD and PCV groups, whereas vitrectomy was performed in 83.7% of eyes with RAM. The final BCVA improved significantly from baseline in the PCV and RAM groups (P = 0.0009, P<0.0001) and final BCVA was significantly better in the PCV group at a level similar to the other groups (P = 0.0007, P = 0.0008). BCVA improvement from baseline was significantly greater in the RAM group compared with the tnAMD (P = 0.0152) and PCV (P = 0.017) groups. Multivariate analysis revealed better final BCVA was significantly associated with younger age (P = 0.0054), better baseline BCVA (P = 0.0021), RAM subtype (P = 0.0446), and no tnAMD (P = 0.001).
Conclusions
The characteristics of, and treatment strategy for, SMH were different between the underlying diseases. Anti-vascular endothelial growth factor treatment with or without expansile gas was mainly chosen for SMH in tnAMD and PCV, whereas vitrectomy with gas was the most common treatment for RAM, and the higher rate for vitrectomy might result in the greater BCVA improvement in the RAM group than in the other groups. Final BCVA was better in PCV, RAM, and tnAMD, in that order, because patients with PCV were younger and had better baseline BCVA
Clinical Characteristics and Outcomes in 314 Japanese Patients with Bacterial Endophthalmitis : A Multicenter Cohort Study from J-CREST
Bacterial endophthalmitis is an intraocular infection that causes rapid vison loss. Pathogens can infect the intraocular space directly (exogenous endophthalmitis (ExE)) or indirectly (endogenous endophthalmitis (EnE)). To identify predictive factors for the visual prognosis of Japanese patients with bacterial endophthalmitis, we retrospectively examined the bacterial endophthalmitis characteristics of 314 Japanese patients and performed statistics using these clinical data. Older patients, with significantly more severe clinical symptoms, were prevalent in the ExE group compared with the EnE group. However, the final best-corrected visual acuity (BCVA) was not significantly different between the ExE and EnE groups. Bacteria isolated from patients were not associated with age, sex, or presence of eye symptoms. Genus Streptococcus, Streptococcus pneumoniae, and Enterococcus were more prevalent in ExE patients than EnE patients and contributed to poor final BCVA. The presence of eye pain, bacterial identification, and poor BCVA at baseline were risk factors for final visual impairment
Real-world management of treatment-naïve diabetic macular oedema : 2-year visual outcome focusing on the starting year of intervention from STREAT-DMO study
Background/aims
To investigate the yearly change of real-world outcomes for best corrected visual acuity (BCVA) after 2-year clinical intervention for treatment-naïve diabetic macular oedema (DMO).
Methods
Retrospective analysis of aggregated, longitudinal medical records obtained from 27 retina specialised institutions in Japan from Survey of Treatment for DMO database. A total of 2049 treatment-naïve centre involving DMO eyes of which the initial intervention started between 2010 and 2015, and had been followed for 2 years, were eligible. As interventions, antivascular endothelial growth factor (VEGF) agents, local corticosteroids, macular photocoagulation and vitrectomy were defined. In each eye, baseline and final BCVA, the number of each intervention for 2 years was extracted. Each eye was classified by starting year of interventional treatment.
Results
Although baseline BCVA did not change by year, 2-year improvement of BCVA had been increased, and reached to +6.5 letters in the latest term. There is little difference among starting year about proportions of eyes which BCVA gained >15 letters, in contrast to those which lost >15 letters were decreased by year. The proportion of eyes receiving anti-VEGF therapy was dramatically increased, while those receiving the other therapies were gradually decreased. The proportion of eyes which maintained socially good vision of BCVA>20/40 has been increased and reached to 59.0% in the latest term.
Conclusion
For recent years, treatment patterns for DMO have been gradually but certainly changed; as a result, better visual gain, suppression of worsened eyes and better final BCVA have been obtained. Anti-VEGF therapy has become the first-line therapy and its injection frequency has been increasing
Diabetic macular edema and aging
Aims/Introduction: In older patients, the management of diabetic macular edema (DME) can be complicated by comorbidities, geriatric syndrome, and socioeconomic status. This study aims to evaluate the effects of aging on the management of DME.
Materials and Methods: This is a real-world clinical study including 1,552 patients with treatment-naïve center-involved DME. The patients were categorized into 4 categories by age at baseline (C1, <55; C2, 55–64; C3, 65–74; and C4, ≥75 years). The outcomes were the change in logarithm of the minimum angle of resolution best-corrected visual acuity (logMAR BCVA) and central retinal thickness (CRT), and the number of treatments from baseline to 2 years.
Results: From baseline to 2 years, the mean changes in logMAR BCVA from baseline to 2 years were −0.01 in C1, −0.06 in C2, −0.07 in C3, and 0.01 in C4 (P = 0.016), and the mean changes in CRT were −136.2 μm in C1, −108.8 μm in C2, −100.6 μm in C3, and −89.5 μm in C4 (P = 0.008). Treatments applied in the 2 year period exhibited decreasing trends with increasing age category on the number of intravitreal injections of anti-VEGF agents (P = 0.06), selecting local corticosteroid injection (P = 0.031), vitrectomy (P < 0.001), and laser photocoagulation outside the great vascular arcade (P < 0.001).
Conclusions: Compared with younger patients with DME, patients with DME aged ≥75 years showed less frequent treatment, a lower BCVA gain, and a smaller CRT decrease. The management and visual outcome in older patients with DME would be unsatisfactory in real-world clinical practice
Real-world management of treatment-naïve diabetic macular oedema in Japan : two-year visual outcomes with and without anti-VEGF therapy in the STREAT-DME study
Background/Aims
To investigate real-world outcomes for best-corrected visual acuity (BCVA) after 2-year clinical intervention for treatment-naïve, centr-involving diabetic macular oedema (DME).
Methods
Retrospective analysis of longitudinal medical records obtained from 27 institutions specialising in retinal diseases in Japan. A total of 2049 eyes with treatment-naïve DME commencing intervention between 2010 and 2015 who were followed for 2 years were eligible. Interventions for DME included anti-vascular endothelial growth factor (VEGF) therapy, local corticosteroid therapy, macular photocoagulation and vitrectomy. Baseline and final BCVA (logMAR) were assessed. Eyes were classified by the treatment pattern, depending on whether anti-VEGF therapy was used, into an anti-VEGF monotherapy group (group A), a combination therapy group (group B) and a group without anti-VEGF therapy (group C).
Results
The mean 2-year improvement of BCVA was −0.04±0.40 and final BCVA of >20/40 was obtained in 46.3% of eyes. Based on the treatment pattern, there were 427 eyes (20.9%) in group A, 807 eyes (39.4%) in group B and 815 eyes (39.8%) in group C. Mean improvement of BCVA was −0.09±0.39, –0.02±0.40 and −0.05±0.39, and the percentage of eyes with final BCVA of >20/40 was 49.4%, 38.9%, and 52.0%, respectively.
Conclusion
Following 2-year real-world management of treatment-naïve DME in Japan, BCVA improved by 2 letters. Eyes treated by anti-VEGF monotherapy showed a better visual prognosis than eyes receiving combination therapy. Despite treatment for DME being selected by specialists in consideration of medical and social factors, a satisfactory visual prognosis was not obtained, but final BCVA remained >20/40 in half of all eyes
Background Factors Affecting Visual Acuity at Initial Visit in Eyes with Central Retinal Vein Occlusion : Multicenter Study in Japan
Purpose: To determine the baseline characteristics of patients with central retinal vein occlusion (CRVO) that were significantly associated with the best-corrected visual acuity (BCVA) at the initial examination. Methods: This was a retrospective multicenter study using the medical records registered in 17 ophthalmological institutions in Japan. Patients with untreated CRVO (≥20-years-of-age) who were initially examined between January 2013 and December 2017 were studied. The patients’ baseline factors that were significantly associated with the BCVA at the initial examination were determined by univariate and multivariate linear regression analyses. Results: Data from 517 eyes of 517 patients were analyzed. Univariate analyses showed that an older age (r = 0.194, p < 0.001) and the right eye (r = −0.103, p < 0.019) were significantly associated with poorer BCVA at the initial visit. Multivariate analyses also showed that an older age (β = 0.191, p < 0.001) and the right eye (β = −0.089, p = 0.041) were significantly associated with poorer BCVA at the initial visit. Conclusions: The results indicate that an older age, a known strong factor, and the right eye were significantly associated with poorer BCVA at the initial visit to the hospital. These results suggest that functional and/or anatomical differences between the right and left eyes may be involved in these results
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