Salidroside, the 8-O-beta-D-glucoside of tyrosol, is a novel adaptogenic drug extracted from the medicinal plant Rhodiola sachalinensis A. Bor. Due to the scarcity of R. sachalinensis and its low yield of salidroside, there is great interest in enhancing the production of salidroside by biotechnological process. Glucosylation of tyrosol is thought to be the final step in salidroside biosynthesis. In our related works, three UGT clones were isolated from the roots and the cultured cells. Our intention was to combine the catalytic specificity of these UGTs in vitro in order to change the level of salidroside in vivo by over-expression of the above UGTs. However, as the aglycone substrate of salidroside, the biosynthetic pathway of tyrosol and its regulation are less well understood. The results of related studies revealed that there are two different possibilities for the tyrosol biosynthetic pathway. One possibility is that tyrosol is produced from a p-coumaric acid precursor, which is derived mainly from phenylalanine. The second possibility is that the precursor of tyrosol might be tyramine, which is synthesized from tyrosine. Our previous work demonstrated that over-expression of the endogenous phenylalanine ammonia-lyase gene (PALrs1) and accumulation of p-coumaric acid did not facilitate tyrosol biosynthesis. In contrast, the data presented in our recent work provide in vitro and in vivo evidence that the tyrosine decarboxylase (RsTyrDC) is most likely to have an important function in the initial reaction of the salidroside biosynthesis pathway in R. Sachalinensis.
Genetic Engineering ; Glucosides ; biosynthesis ; Glycosylation ; Phenols ; Phenylethyl Alcohol ; analogs & derivatives ; chemistry ; metabolism ; Rhodiola ; metabolism ; Tyrosine ; metabolism ; Tyrosine Decarboxylase ; metabolism

Female ; Humans ; Male ; Myocardial Infarction ; drug therapy ; therapy ; Percutaneous Coronary Intervention ; methods ; Tyrosine ; analogs & derivatives

Acute Disease ; Humans ; Male ; Middle Aged ; Thrombocytopenia ; chemically induced ; Tyrosine ; adverse effects ; analogs & derivatives

Acute Coronary Syndrome ; drug therapy ; Angioplasty, Balloon, Coronary ; Aspirin ; administration & dosage ; Humans ; Platelet Aggregation Inhibitors ; administration & dosage ; Thrombelastography ; Ticlopidine ; administration & dosage ; analogs & derivatives ; Tyrosine ; administration & dosage ; analogs & derivatives

Minor fibrillar collagen types V and XI, are those less abundant than the fibrillar collagen types I, II and III. The alpha chains share a high degree of similarity with respect to protein sequence in all domains except the variable region. Genomic variation and, in some cases, extensive alternative splicing contribute to the unique sequence characteristics of the variable region. While unique expression patterns in tissues exist, the functions and biological relevance of the variable regions have not been elucidated. In this review, we summarize the existing knowledge about expression patterns and biological functions of the collagen types V and XI alpha chains. Analysis of biochemical similarities among the peptides encoded by each exon of the variable region suggests the potential for a shared function. The alternative splicing, conservation of biochemical characteristics in light of low sequence conservation, and evidence for intrinsic disorder, suggest modulation of binding events between the surface of collagen fibrils and surrounding extracellular molecules as a shared function.
Alternative Splicing ; genetics ; Animals ; Fibrillar Collagens ; chemistry ; genetics ; metabolism ; Humans ; Sulfates ; chemistry ; metabolism ; Surface Properties ; Tyrosine ; analogs & derivatives ; chemistry ; metabolism

Rapid arterial rethrombosis is associated with high-grade residual stenosis and usually occurs at the site of the initial occlusion, resulting in reocclusion of the recanalized artery. Platelets may play an active role in such rethrombosis after thrombolytic-induced clot lysis. Given that glycoprotein IIb/IIIa receptor blockers, like tirofiban, prevent thrombus formation by inhibiting the final common pathway of platelet aggregation, they may be helpful for treating rethrombosis after thrombolysis. A 64-year-old man presented with an acute ischemic stroke due to internal carotid artery (ICA) occlusion. The ICA was recanalized by intravenous thrombolysis but reoccluded shortly after recanalization. The reoccluded ICA was successfully recanalized using intra-arterial tirofiban. A carotid stent was subsequently inserted to relieve severe stenosis and to prevent recurrent stroke. Here, we report a case of rescue treatment of a successfully recanalized ICA by intra- arterial tirofiban. We suggest that rescue use of intra-arterial tirofiban may be effective and safe, especially in hemorrhage prone situations, due to the relatively lower dose of tirofiban compared with intravenous doses.
*Carotid Artery, Internal ; Carotid Stenosis/*drug therapy/radiography/surgery ; Emergency Treatment ; Humans ; Infusions, Intra-Arterial ; Male ; Middle Aged ; Stents ; Tyrosine/administration & dosage/*analogs & derivatives/therapeutic use

Angioplasty, Balloon, Coronary ; methods ; Humans ; Myocardial Infarction ; therapy ; Platelet Aggregation Inhibitors ; administration & dosage ; therapeutic use ; Tyrosine ; administration & dosage ; analogs & derivatives ; therapeutic use

BACKGROUNDTransradial access has been increasingly used during primary percutaneous coronary intervention (PCI) for patients with acute ST-segment elevation myocardial infarction (STEMI) in last decade. Clinical benefits of upstream use of tirfiban therapy in STEMI patients treated by primary PCI have been reported. We investigated the merits of transradial vs. transfemoral access in primary PCI for STEMI patients with upstream use of tirofiban.

METHODSPatients with STEMI treated with tirofiban between December 2006 and October 2012 then by primary PCI were compared between transradial (n = 298) and transfemoral (n = 314) access. Baseline demographics, angiographic and PCI features and primary endpoint of major adverse cardiac events (MACE) at 30-day clinical follow-up were recorded.

RESULTSBaseline and procedural characteristics were comparable between the two groups, apart from more patients in transradial group had hypertension and were treated by thrombus aspiration during primary PCI. Significantly fewer MACE occurred in the transradial group (5.4%) compared with the transfemoral group (9.9%) at 30-day clinical follow-up. Major bleeding events at 30-day clinical follow-up were 0 in transradial group and in 2.9% of transfemoral group. Multivariate analysis confirmed transradial approach as an independent negative predictor of 30-day MACE (HR 0.68; 95%CI 0.35 - 0.91; P = 0.03).

CONCLUSIONSUsing transradial approach in primary PCI for acute STEMI infarction patients treated with tirofiban was clearly beneficial in reducing bleeding complications and improving 30-day clinical outcomes.

Aged ; Angioplasty, Balloon, Coronary ; Female ; Humans ; Male ; Middle Aged ; Myocardial Infarction ; drug therapy ; therapy ; Percutaneous Coronary Intervention ; methods ; Tyrosine ; analogs & derivatives ; therapeutic use

Humans ; Leukemia, Myeloid, Acute ; drug therapy ; genetics ; Male ; Middle Aged ; Mutation ; Niacinamide ; analogs & derivatives ; therapeutic use ; Phenylurea Compounds ; therapeutic use ; fms-Like Tyrosine Kinase 3 ; genetics

BACKGROUNDModern research has provided new insights into the biological mechanisms of noise-induced hearing loss, and a number of studies showed the appearance of increased reactive oxygen species (ROS) and reactive nitrogen species (RNS) during and after noise exposure. This study was designed to investigate the noise exposure induced nitrotyrosine change and the mechanism of outer hair cells death in guinea pig cochlea.

METHODThirty guinea pigs were used in this study. The experimental animals were either exposed for 4 hours per day to broadband noise at 122 dB SPL (A-weighted) for 2 consecutive days or perfused cochleae with 5 mg/ml of the SIN1 solutions, an exogenous NO and superoxide donor, for 30 minutes. Then the cochleae of the animals were dissected. Propidium iodide (PI), a DNA intercalating fluorescent probe, was used to trace morphological changes in OHC nuclei. The distribution of nitrotyrosine (NT) in the organ of Corti and the cochlear lateral wall tissue from the guinea pigs were examined using fluorescence immunohistochemistry method. Whole mounts of organ of Corti were prepared. Morphological and fluorescent changes were examined under a confocal microscope.

RESULTSEither after noise exposure or after SIN1 perfusion, outer hair cells (OHCs) death with characteristics of both apoptotic and necrotic degradation appeared. Nitrotyrosine immunolabeling could be observed in the OHCs from the control animals. After noise exposure, NT immunostaining became much greater than the control animals in OHCs. The apoptotic OHC has significant increase of nitrotyrosine in and around the nucleus following noise exposure. In the normal later wall of cochleae, relatively weak nitrotyrosine immunolabeling could be observed. After noise exposure, nitrotyrosine immunoactivity became stronger in stria vascularis.

CONCLUSIONNoise exposure induced increase of nitrotyrosine production is associated with OHCs death suggesting reactive nitrogen species participation in the cochlear pathophysiology of noise-induced hearing loss.

Animals ; Cell Death ; Cochlea ; chemistry ; pathology ; Female ; Guinea Pigs ; Hair Cells, Auditory, Outer ; pathology ; Immunohistochemistry ; Male ; Noise ; adverse effects ; Organ of Corti ; chemistry ; pathology ; Tyrosine ; analogs & derivatives ; analysis