ABSTRACT
Ubiquitin-proteasome system (UPS) is the important protein degradation system in eukaryotic cells, participates in cell cycle, gene transcription, antigen-presenting, cell proliferation and differentiation, signal transduction and many other physiological processes.UPS dysfunction relates to pathogenic mechanisms in a variety of diseases such as cancer, neurodegenerative diseases and cardiovascular disease.In recent years, more and more researches confirmed that UPS exists in the retina, some retinal damage appeared in patients with neurodegenerative conditions.UPS is involved in the pathogenesis of diabetic retinopathy, age-related macular degeneration, macular pigment degeneration and other retinal diseases by regulating retinal oxidative stress, inflammation, angiogenesis, nerve damage, signal transduction and so on.Some signaling pathways, such as nuclear factor κB (NF-κB), transforming growth factor-β (TGF-β) and reactive oxygen species (ROS) play an important role.Their proteins degradation and synthesis of imbalances have a significant impact on the pathophysiological process of retinal diseases.Proteasome inhibitors can reduce inflammation pathological changes in retinal lesions.This review focused on the research progress of UPS in the development of retinopathy.
ABSTRACT
ObjectiveTo evaluate the efficacy of nerve stimulator-guided thoracic paravertebral block in patients undergoing segmental mastectomy.MethodsFifty ASA Ⅰ or Ⅱ female patients,aged 18-64 yr,with body mass index ＜ 24 kg/m2,undergoing segmental mastectomy,were randomly divided into 2 groups ( n =25 each):thoracic epidural block group (group A) and nerve stimulator-guided thoracic paravertebral block group (group B).In group A,an epidural catheter was placed at T3,4 interspace and 0.5％ ropivacaine 7-10 ml was administrated via the epidural catheter.In group B,thoracic paravertebral block was performed at T4 under the guide of the nerve stimulator and 0.5％ ropivacaine 25 ml was administrated.The perioperative adverse cardiovascular events (hypotension and bradycardia) were recorded.Shivering,chest distress,and dyspnea during operation and nausea and vomiting after operation were also recorded.The range of block on the operated side was determined by pinprick test.The efficacy of anesthesia was evaluated.ResultsThe incidence of shivering,chest distress,and dyspnea during operation and nausea and vomiting after operation was significantly lower in group B than in group A (P ＜ 0.05).Adverse cardiovascular events and respiratory depression were not found in the two groups.There was no significant difference in the range of block on the operated side in the two groups ( P ＞ 0.05).The satisfactory anesthesia was found in 100％ of cases.ConclusionNerve stimulator-guided thoracic paravertebral block can be safely and effectively used in patients undergoing segmental mastectomy and the efficacy is better than that of thoracic epidural block.