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1.
Tengzhi Liu Kathrine Røe Redalen Morten Karlsen 《Journal of labelled compounds & radiopharmaceuticals》2022,65(7):191-202
Cyclotron-produced copper-64 radioisotope tracers offer the possibility to perform both diagnostic investigation by positron emission tomography (PET) and radiotherapy by a theranostic approach with bifunctional chelators. The versatile chemical properties of copper add to the importance of this isotope in medicinal investigation. [64Cu][Cu (ATSM)] has shown to be a viable candidate for imaging of tumor hypoxia; a critical tumor microenvironment characteristic that typically signifies tumor progression and resistance to chemo-radiotherapy. Various production and radiosynthesis methods of [64Cu][Cu (ATSM)] exist in labs, but usually involved non-standardized equipment with varying production qualities and may not be easily implemented in wider hospital settings. [64Cu][Cu (ATSM)] was synthesized on a modified GE TRACERlab FXN automated synthesis module. End-of-synthesis (EOS) molar activity of [64Cu][Cu (ATSM)] was 2.2–5.5 Ci/μmol (HPLC), 2.2–2.6 Ci/μmol (ATSM-titration), and 3.0–4.4 Ci/μmol (ICP-MS). Radiochemical purity was determined to be >99% based on radio-HPLC. The final product maintained radiochemical purity after 20 h. We demonstrated a simple and feasible process development and quality control protocols for automated cyclotron production and synthesis of [64Cu][Cu (ATSM)] based on commercially distributed standardized synthesis modules suitable for PET imaging and theranostic studies. 相似文献
2.
《Value in health》2022,25(7):1235-1252
ObjectivesThe incidence of type 1 diabetes mellitus is increasing every year requiring substantial expenditure on treatment and complications. A systematic review was conducted on the cost-effectiveness of insulin formulations, including ultralong-, long-, or intermediate-acting insulin, and their biosimilar insulin equivalents.MethodsMEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, HTA, and NHS EED were searched from inception to June 11, 2021. Cost-effectiveness and cost-utility analyses were included if insulin formulations in adults (≥ 16 years) with type 1 diabetes mellitus were evaluated. Two reviewers independently screened titles, abstracts, and full-text articles, extracted study data, and appraised their quality using the Drummond 10-item checklist. Costs were converted to 2020 US dollars adjusting for inflation and purchasing power parity across currencies.ResultsA total of 27 studies were included. Incremental cost-effectiveness ratios ranged widely across the studies. All pairwise comparisons (11 of 11, 100%) found that ultralong-acting insulin was cost-effective compared with other long-acting insulins, including a long-acting biosimilar. Most pairwise comparisons (24 of 27, 89%) concluded that long-acting insulin was cost-effective compared with intermediate-acting insulin. Few studies compared long-acting insulins with one another.ConclusionsLong-acting insulin may be cost-effective compared with intermediate-acting insulin. Future studies should directly compare biosimilar options and long-acting insulin options and evaluate the long-term consequences of ultralong-acting insulins. 相似文献
3.
《Patient education and counseling》2022,105(11):3225-3234
ObjectiveTo identify how peer support interventions, for self-management of chronic pain, support basic psychological needs from a self-determination theory (SDT) perspective, using a systematic review.MethodsTen databases were searched for studies reporting qualitative research about peer interactions in pain management interventions. ‘Best fit’ framework synthesis methodology was applied to identify strategies that support the satisfaction of competence, autonomy and motivation. These were matched to definitions of strategies provided by standardised taxonomies.Results18 studies were selected for inclusion. The synthesis resulted in a conceptual model, identifying 12 peer strategies that support psychological needs for self-management of chronic pain; 10 overlapped with existing taxonomies.ConclusionThis was the first known attempt to synthesise evidence about peer support strategies for people living with pain, using SDT as an a priori framework. The model demonstrates commonality between the motivation-promoting processes of peer support and those of other behaviour change interventions and identifies additional unique strategies provided by peers. This systematic classification of peer support strategies provides a means for future study of the efficacy and comprehensiveness of peer interventions.Practice implicationsThe model could assist healthcare professionals and support groups to optimise the potential of peer processes. 相似文献
4.
《药学学报(英文版)》2020,10(2):327-343
Our recent studies demonstrated that the natural product nobiletin (NOB) served as a promising multidrug resistance (MDR) reversal agent and improved the effectiveness of cancer chemotherapy in vitro. However, low aqueous solubility and difficulty in total synthesis limited its application as a therapeutic agent. To tackle these challenges, NOB was synthesized in a high yield by a concise route of six steps and fourteen derivatives were synthesized with remarkable solubility and efficacy. All the compounds showed improved sensitivity to paclitaxel (PTX) in P-glycoprotein (P-gp) overexpressing MDR cancer cells. Among them, compound 29d exhibited water solubility 280-fold higher than NOB. A drug-resistance A549/T xenograft model showed that 29d, at a dose of 50 mg/kg co-administered with PTX (15 mg/kg), inhibited tumor growth more effective than NOB and remarkably increased PTX concentration in the tumors via P-gp inhibition. Moreover, Western blot experiments revealed that 29d inhibited expression of NRF2, phosphorylated ERK and AKT in MDR cancer cells, thus implying 29d of multiple mechanisms to reverse MDR in lung cancer. 相似文献
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Y. Chen B. Bai H. Yan F. Wen D. Qin G. Jander Q. Xia G. Wang 《Insect molecular biology》2019,28(3):380-391
Isopentenylation at A37 (i6A37) of some transfer RNAs (tRNAs) plays a vital role in regulating the efficiency and fidelity of protein synthesis. However, whether insects, which are well known for their highly efficient protein synthesis machinery, employ this regulatory mechanism remains uninvestigated. In the current study, a candidate tRNA isopentenyltransferase (IPT) gene with three alternative splicing isoforms (BmIPT1–BmIPT3) was identified in Bombyx mori (silkworm). Only BmIPT1 could complement a yeast mutant lacking tRNA IPT. Phylogenetic analysis showed that silkworm tRNA IPT is conserved in the Lepidoptera. BmIPT was expressed in all B. mori tissues and organs that were investigated, but was expressed at a significantly higher level in silk glands of the fourth instar compared to the first day of the fifth instar. Interestingly, BmIPT was expressed at a significantly higher level in the domesticated silkworm, B. mori, than in wild Bombyx mandarina in multiple tissues and organs. Knock‐down of BmIPT by RNA interference caused severe abnormalities in silk spinning and metamorphosis. Constitutive overexpression of BmIPT1 using a cytoplasmic actin 4 promoter in B. mori raised its messenger RNA level more than sixfold compared with nontransgenic insects and led to significant decreases in the body weight and cocoon shell ratio. Together, these results confirm the first functional tRNA IPT in insects and show that a suitable expression level of tRNA IPT is vital for silk spinning, normal growth, and metamorphosis. Thus, i6A modification at position A37 in tRNA probably plays an important role in B. mori protein synthesis. 相似文献
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目的探讨PDCA(Plan计划,Do执行,Check检查,Action行动)循环法在自动乳腺全容积成像(ABVS)诊断乳腺疾病中的应用。 方法收集中南大学湘雅三医院2018年1月至2019年12月期间行ABVS检查并经病理确诊或临床明确诊断的乳腺疾病患者2070例,根据PDCA循环法应用时间分为2组,PDCA循环法应用前(2018年1月至2018年12月)患者840例,PDCA循环法应用后(2019年1月至2019年12月)患者1230例。使用χ2检验分析比较PDCA循环法应用前后的诊断符合率、漏诊率、误诊率以及患者满意度的差异。 结果与PDCA循环法应用前比较,PDCA实施后ABVS诊断符合率提高(87.89% vs 82.74%),误诊率下降(11.47% vs 15.63%),漏诊率下降(14.39% vs 23.20%),患者满意度提升(92.59% vs 87.12%),差异均具有统计学意义(χ2=10.856、4.507、3.936、3.922,P=0.010、0.034、0.047、0.048)。 结论PDCA循环法能提升ABVS诊断乳腺疾病过程中的医疗质量。 相似文献
10.
《Survey of ophthalmology》2022,67(6):1647-1684
Managing pediatric corneal disorders is challenging as the prognosis of pediatric keratoplasty depends on several factors. Advancements in the genetic basis of congenital corneal diseases and investigations in congenital corneal conditions provide a better understanding of pediatric corneal conditions. Surgeons performing keratoplasty in children now have a choice of various techniques. Evolving surgical techniques of anterior lamellar and endothelial keratoplasties have expanded the management interventions in these pediatric corneal morbidity conditions; however, considerable concerns still exist in association with corneal transplantation in infants and children. Outcomes in pediatric keratoplasty depend upon the preoperative indications, the timing of surgical intervention, intraoperative and postoperative factors including the patient/care givers’ compliance. Factors such as low scleral rigidity, higher rate of graft failure, need for frequent examinations under anesthesia, and difficulty in optimal visual acuity assessment still remain a considerable challenge in pediatric scenarios. In children, deprivation amblyopia as a result of the corneal opacification can adversely affect visual development, causing dense amblyopia. Outcomes to surgical interventions for management of corneal opacification in children are further compromised by the preexisting amblyopia apart from the concerns of refractive outcome of the graft. Graft rejection, graft infection, amblyopia, and glaucoma continue to be serious concerns. In recent years both anterior and posterior lamellar keratoplasty techniques are being increasingly performed in pediatric eyes, which offer advantages in the form of lower risk of graft rejection. The timing of surgery, careful case selection, cautious intraoperative approach, and optimal postoperative management can improve the anatomical and functional outcome in difficult cases. 相似文献