Parkinson's disease (PD) is a progressive disease related to degeneration of nigrostriatal dopaminergic neurons and can be caused by genetic and environmental factors. N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) can produce Parkinsonian syndrome (Langston et al. 1983) and is an Received February 28, 2010; revised manuscript received April 26, 2010; accepted April 26, 2010. Address correspondence and reprint requests to Kai-Yuan Tzen, MD, Department of Nuclear Medicine, National Taiwan University Hospital, No.7 Chung Shan South Road, Taipei 100, Taiwan. E-mail: tzenky@ntuh.gov.tw or Chun-Jung Lin, School of Pharmacy, College of Medicine, National Taiwan University,1 Jen-Ai Road, Section 1, Taipei, Taiwan 100. E-mail: clementumich@ntu.edu.tw Abbreviations used: 3-MT, 3-methoxytyramine; ARBECs, adult rat brain endothelial cells; AUC, area under the time-concentration curve; BB, blood-brain barrier; BMECs, brain microvessel endothelial cells; BSA, bovine serum albumin; DC, detergent compatible; DOPAC, 3,4-dihydroxyphenylacetic acid; ECF, extracellular fluid; FDOPA, 6-[ AbstractThe cellular localization of organic cation transporter (OCT) 1 and OCT2 in isolated brain microvessel endothelial cells from humans, rats, and mice and in cultured adult rat brain endothelial cells was examined by confocal microscopy and in isolated luminal and abluminal membrane fractions by Western blot analysis. Cellular uptake of N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was measured with or without OCT1/OCT2 silencing. The interaction between MPTP and amantadine was studied by in vitro kinetic analysis and in vivo brain microdialysis. MPTP-induced dopaminergic toxicity was examined by measuring dopamine levels in the brain striatum and by positron emission tomography scanning. The results showed that both OCT1 and OCT2 were mainly expressed on the luminal side of brain microvessel endothelial cells and adult rat brain endothelial cells. Cellular uptake of MPTP was significantly (p < 0.05) decreased by about 53%, 60%, or 91% following silencing of OCT1, OCT2, or both, respectively. Amantadine competitively inhibited MPTP uptake in vitro and significantly (p < 0.05) reduced the area under the time-concentration curve for MPTP and MPP + in the brain extracellular fluid in rats and mice by 65-70% and 35-85%, respectively. MPTP-induced dopaminergic toxicity in mice was ameliorated by amantadine without stimulating dopamine turnover. In conclusion, OCT1 and OCT2 are important for MPTP transfer across the blood-brain barrier and amantadine reduces the blood-brain barrier transfer of MPTP and MPTP-induced dopaminergic toxicity in rodents.
Neutrophil extracellular traps (NETs), which consist of neutrophil DNA and cytoplasmic proteins, have been shown to be involved in various infectious, inflammatory, and autoimmune diseases. Neutrophil extracellular traps are abundant at the site of infection and acute inflammation. Neutrophil extracellular trap formation can occur through various intracellular signaling pathways, including peptidylarginine deiminase 4, Raf-MEK-ERK, nitric oxide, Toll-like receptor 4, high mobility group box 1, pentraxin 3, and mammalian targets of rapamycin. A growing body of evidence indicates that NETs may play an important role in injury, and decreases in NETs could reduce tissue injury. Neutrophil extracellular traps are believed to modulate the inflammatory and immune responses of individuals after injury. In this review, the role of NETs in injury, including traumatic injury, ischemia-reperfusion-induced injury, and sepsis, as well as the potential markers and therapeutic targets of NET-related injury will be discussed.
Our reported cutoffs can serve as criterion-referenced values, along with those previously determined using different indicators, and provide important landmarks on the performance continua of older adults' grip strength and UGS. These landmarks could be useful in interpreting test results, monitoring changes in performance, and identifying individuals requiring timely intervention. For identifying older adults at risk of IADL disability, grip strength is superior to UGS.
Although only 1% of differentiated thyroid cancers transform into anaplastic thyroid cancer, this disease is always fatal. Differentiation therapy may provide a new therapeutic approach to increasing the survival rate in such patients. 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors are reported to promote cellular apoptosis and differentiation in many cancer cells; these effects are unrelated to lipid reduction. Recently, we found that TNFalpha induces cytomorphological differentiation in anaplastic thyroid cancer cells and increases thyroglobulin expression; however, TNF is cytotoxic for normal human tissue. The aim of this study was to determine whether lovastatin, an HMG-CoA reductase inhibitor, could induce apoptosis and differentiation in anaplastic thyroid cancer cells. Anaplastic thyroid cancer cells were treated with lovastatin, then examined for cellular apoptosis and cytomorphological differentiation by DNA fragmentation, phosphatidylserine externalization/flow cytometry, and electron microscopy. Thyroglobulin levels in the culture medium were also measured. Our results showed that at a higher dose (50 micro M), lovastatin induced apoptosis of anaplastic thyroid cancer cells, whereas at a lower dose (25 micro M), it promoted 3-dimensional cytomorphological differentiation. It also induced increased secretion of thyroglobulin by anaplastic cancer cells. Our results show that lovastatin not only induces apoptosis, but also promotes redifferentiation in anaplastic thyroid cancer cells, and suggest that it and other HMG-CoA reductase inhibitors merit further investigation as differentiation therapy for the treatment of anaplastic thyroid cancer.
Enhanced activity of neutrophil elastase leads to a protease–antiprotease imbalance, and plays an essential pathogenic role in acute lung injury (ALI) and acute respiratory distress syndrome. We assayed the pharmacological effects and mechanisms of the action of sirtinol in human neutrophils, and in neutrophil elastase (HNE)-induced paw edema and lipopolysaccharide (LPS)-mediated ALI in mice. Sirtinol significantly inhibited the activity of HNE from human neutrophils in response to various stimulators. The inhibitory effects on HNE activity were not mediated through protein kinase A, calcium, extracellular-regulated kinase, c-Jun N-terminal kinase, p38 mitogen-activated protein kinase, Akt, or Src family kinases. Analysis of enzymatic activities showed that sirtinol inhibited HNE activity in a concentration-dependent manner. These results demonstrate that sirtinol does not affect neutrophil function and is an HNE inhibitor. In addition, administration of sirtinol significantly inhibited HNE-induced paw edema, and attenuated the myeloperoxidase activity and reduced pulmonary wet/dry weight ratio in the LPS-induced ALI mouse model. Our study indicates that sirtinol has anti-inflammatory effects through direct inhibition of HNE activity and attenuates HNE-induced and LPS-mediated tissue or organ injury in vivo. Sirtinol is a novel HNE inhibitor and may have the potential for clinical application in the treatment of inflammatory lung diseases.
According to this review of recent NE inhibitor patents, all of the disclosed inhibitors can be classified into peptide- and non-peptide-based groups. The non-peptide NE inhibitors include heterocyclics, uracil derivatives and deuterium oxide. Among the heterocyclic analogs, derivatives of pyrimidinones, tetrahydropyrrolopyrimidinediones, pyrazinones, benzoxazinones and hypersulfated disaccharides were introduced. The literature has increasingly implicated NE in the pathogenesis of various diseases, of which inflammatory destructive lung diseases remain a major concern. However, only a few agents have been validated for therapeutic use in clinical settings to date.
BackgroundThe “Rusch” intubation stylet is used to make endotracheal tube intubation easy. We designed this study to evaluate the usage of this equipment in the guidance of nasogastric tube (NGT) insertion.MethodsA total of 103 patients, aged 23 to 70 years, undergoing gastrointestinal or hepatic surgeries that required intraoperative NGT insertions were enrolled into our study. The patients were randomly allocated to the control group (Group C) or the stylet group (Group S) according to a computerized, random allocation software program. In the control group, the NGT was inserted with the patient’s head in an intubating position. In the stylet group, the NGT was inserted with the assistance of a “Rusch” intubation stylet tied together at the tips by a slipknot. The success rates of the two methods, the durations of the insertions, and the occurrences of complications were recorded. All of the failed cases in the control group were subjected to the new technique used in the stylet group, and the successful rescue rate was also evaluated.ResultsSuccessful insertions were recorded for 52/53 patients (98.1%) in Group S and for 32/50 patients (64%) in Group C. The mean insertion times were 39.5 ± 19.5 seconds in Group C and 40.3 ± 23.2 seconds in Group S. Successful rescues of failure cases in Group C were achieved in 17/18 patients (94.4%) with the assistance of a “Rusch” intubation stylet.ConclusionsThe “Rusch” intubation stylet-guided method is reliable with a high success rate of NGT insertion in anesthetized and intubated patients.Trial registrationInstitutional Review Board of Chang Gung Memorial Hospital (IRB: 98-2669B) and Australian New Zealand Clinical Trials Registry (ACTRN12611000423910)
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