Parkinson's disease (PD), a neurological disease suited to gene therapy, is biochemically characterized by a severe decrease in the dopamine content of the striatum. One current strategy for gene therapy of PD involves local production of dopamine in the striatum achieved by inducing the expression of enzymes involved in the biosynthetic pathway for dopamine. We previously showed that the coexpression of tyrosine hydroxylase (TH) and aromatic-L-amino-acid decarboxylase (AADC), using two separate adeno-associated virus (AAV) vectors, resulted in more effective dopamine production and more remarkable behavioral recovery in 6-hydroxydopamine-lesioned parkinsonian rats, compared with the expression of TH alone. Not only levels of TH and AADC but also levels of tetrahydrobiopterin (BH4), a cofactor of TH, and GTP cyclohydrolase I (GCH), a rate-limiting enzymes for BH4 biosynthesis, are reduced in parkinsonian striatum. In the present study, we investigated whether transduction with separate AAV vectors expressing TH, AADC, and GCH was effective for gene therapy of PD. In vitro experiments showed that triple transduction with AAV-TH, AAV-AADC, and AAV-GCH resulted in greater dopamine production than double transduction with AAV-TH and AAV-AADC in 293 cells. Furthermore, triple transduction enhanced BH4 and dopamine production in denervated striatum of parkinsonian rats and improved the rotational behavior of the rats more efficiently than did double transduction. Behavioral recovery persisted for at least 12 months after stereotaxic intrastriatal injection. These results suggest that GCH, in addition to TH and AADC, is important for effective gene therapy of PD.
The Chinese version of the TMT is reliable for detecting AD or VaD but poor at distinguishing MCI from NC.
These results suggest that the depressed cardiac function of end-stage myocardial hypertrophy may be due, in part, to altered contractile protein function.
Background New therapies are urgently needed for Alzheimer’s disease (AD). Sodium oligomannate (GV-971) is a marine-derived oligosaccharide with a novel proposed mechanism of action. The first phase 3 clinical trial of GV-971 has been completed in China. Methods We conducted a phase 3, double-blind, placebo-controlled trial in participants with mild-to-moderate AD to assess GV-971 efficacy and safety. Participants were randomized to placebo or GV-971 (900 mg) for 36 weeks. The primary outcome was the drug-placebo difference in change from baseline on the 12-item cognitive subscale of the Alzheimer’s Disease Assessment Scale (ADAS-cog12). Secondary endpoints were drug-placebo differences on the Clinician’s Interview-Based Impression of Change with caregiver input (CIBIC+), Alzheimer’s Disease Cooperative Study-Activities of Daily Living (ADCS-ADL) scale, and Neuropsychiatric Inventory (NPI). Safety and tolerability were monitored. Results A total of 818 participants were randomized: 408 to GV-971 and 410 to placebo. A significant drug-placebo difference on the ADAS-Cog12 favoring GV-971 was present at each measurement time point, measurable at the week 4 visit and continuing throughout the trial. The difference between the groups in change from baseline was − 2.15 points (95% confidence interval, − 3.07 to − 1.23; p < 0.0001; effect size 0.531) after 36 weeks of treatment. Treatment-emergent adverse event incidence was comparable between active treatment and placebo (73.9%, 75.4%). Two deaths determined to be unrelated to drug effects occurred in the GV-971 group. Conclusions GV-971 demonstrated significant efficacy in improving cognition with sustained improvement across all observation periods of a 36-week trial. GV-971 was safe and well-tolerated. Trial registration ClinicalTrials.gov, NCT02293915. Registered on November 19, 2014
S pontaneous intracerebral hemorrhage (ICH) accounts for 10% to 15% of all strokes and is one of the leading causes of stroke-related mortality and morbidity worldwide. Patients with ICH are generally at risk of developing stroke-associated pneumonia (SAP) during acute hospitalization. Evidence has shown that SAP not only increases the length of hospital stay (LOS) and medical cost 1,2 but also is an important risk factor of mortality and morbidity after acute stroke. 3,4 Several risk factors for SAP have been identified, such as older age, 4-12 male sex, 5,6,10,11,13 current smoking, 12 diabetes mellitus, 6 hypertension, 14 atrial fibrillation, 7,10,12 congestive heart failure, 7,12,13,15 chronic obstructive pulmonary disease, 8,[12][13][14] preexisting dependency, 8,12,13,16 stroke severity, 5,6,8,12,17,18 dysphagia, [8][9][10][11][12]14,[18][19][20] and blood glucose. 12 Meanwhile, based on these risk factors, a few risk models have been developed for SAP after acute ischemic stroke. [8][9][10][11][12] Currently, no valid scoring system is available for predicting SAP after ICH in routine clinical practice or clinical trial. We hypothesized that there might be some common grounds for the development of pneumonia after acute ischemic stroke and ICH, and those predictors for SAP after acute ischemic stroke might also be useful for predicting SAP after ICH. For clinical practice, an effective risk-stratification and prognostic model for SAP after ICH would be helpful to identify vulnerable patients, allocate relevant medical resources, and implement tailored preventive strategies. In addition, for clinical trial, it could be used in nonrandomized studies to control for case-mix variation and in controlled studies as a selection criterion.Background and Purpose-We aimed to develop a risk score (intracerebral hemorrhage-associated pneumonia score, ICH-APS) for predicting hospital-acquired stroke-associated pneumonia (SAP) after ICH. Methods-The ICH-APS was developed based on the China National Stroke Registry (CNSR), in which eligible patients were randomly divided into derivation (60%) and validation (40%) cohorts. Variables routinely collected at presentation were used for predicting SAP after ICH. For testing the added value of hematoma volume measure, we separately developed 2 models with (ICH-APS-B) and without (ICH-APS-A) hematoma volume included. Multivariable logistic regression was performed to identify independent predictors. The area under the receiver operating characteristic curve (AUROC), Hosmer-Lemeshow goodness-of-fit test, and integrated discrimination index were used to assess model discrimination, calibration, and reclassification, respectively. Results-The SAP was 16.4% and 17.7% in the overall derivation (n=2998) and validation (n=2000) cohorts, respectively.A 23-point ICH-APS-A was developed based on a set of predictors and showed good discrimination in the overall derivation (AUROC, 0.75; 95% confidence interval, 0. Ji et al Risk Score to Predict SAP After ICH 2621In the study, we aimed to ...
Alzheimer's disease (AD), the most common form of dementia, is characterized by the presence of excessive deposits of aggregated amyloid-beta (Abeta), which is derived from the amyloid-beta protein precursor (AbetaPP) following processing by beta- and gamma-secretase. Metal elements are implicated in the pathophysiology of AD. Magnesium affects many biochemical mechanisms vital for neuronal properties and synaptic plasticity, and magnesium levels were reported to be decreased in various tissues including brain of AD patients. However, the exact role of magnesium in the neurodegenerative process of AD remains elusive. In this study, we investigated the effects of physiological (0.8 mM, as normal control), low (0-0.4 mM), and high (1.2-4.0 mM) concentrations of extracellular magnesium ([Mg2+]o) on AbetaPP processing and Abeta secretion. Here we show the effects of varying [Mg2+]o on AbetaPP processing is time- and dose-dependent. After 24 h treatment, high [Mg2+]o increased C-terminal fragment-alpha (CTFalpha) levels and soluble alpha-secretase cleaved AbetaPP (sAbetaPPalpha) release via enhancing retention of AbetaPP on plasma membrane. In contrast, low [Mg2+]o enhanced CTFbeta accumulation and Abeta secretion, and reduced cell surface AbetaPP level. Varying [Mg2+]o did not alter protein contents of full length AbetaPP. However, decreased total intracellular magnesium level by magnesium deprivation over 24 hr impaired cell viability. Normal AbetaPP processing could be restored when magnesium was adjusted back to physiological concentration. These data demonstrate that AbetaPP processing can be modulated by magnesium and at high [Mg2+]o, AbetaPP processing favors the alpha-secretase cleavage pathway. Our findings suggest that supplementation of magnesium has a therapeutic potential for preventing AD.
We studied contractile function in cardiac trabeculae isolated from the right ventricles (RV) of rats with experimental heart failure (HF) induced by left ventricular (LV) myocardial infarction (24 wk post-MI; n = 6) and from sham-operated rats (n = 7). Sarcomere length (SL) was measured by laser diffraction techniques, and force (F) was measured by silicon strain gauge. SL was kept constant at all times by computer feedback control. HF was associated with marked LV dilation and pulmonary congestion. In intact, RV twitching trabeculae, HF was associated with a depression of the F-SL relation at extracellular Ca2+ concentration ([Ca2+]o) = 1.5 mM and a depression of the F-[Ca2+]o relation at SL = 2.0 microns. HF was also associated with a significant depression of the F-intracellular [Ca2+] relation at SL = 2.0 microns measured after chemical permeabilization of these RV trabeculae (skinned fibers). Our results suggest that reduced force development in this model of HF is due, in part, to depressed function of the contractile filaments.
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