Age-related RGC loss of up to 50% can occur in the C57 mouse by 18 months of age. The loss does not proceed linearly with age, as is often assumed, and differs both in extent and locational pattern from pathologic RGC loss secondary to glaucoma in DBA/2NNia mouse retinas.
Episcleral vein cauterization (EVC) is used in rats to generate a glaucoma model with high intraocular pressure (IOP). The long-term retinal damage in this glaucoma model however, has not been accurately quantified. We report the location and amount of retinal ganglion cell (RGC) damage caused by (EVC) induced IOP elevation in two rat strains.IOP was raised in one eye of Wistar(N=5) and Brown-Norway(B-N)(N=7) rats by EVC and monitored monthly until IOP in contralateral eyes equalized at 5 months post-surgery. Animals were maintained for 3.5-4.5 additional months. B-N rats(N=7) that had no EVC served as controls for this strain. Scotopic flash ERGs were recorded at baseline and just prior to euthanasia. Automated counts of all retrogradely labeled RGCs in retinal flat-mounts were determined and compared between contralateral eyes. RGC density maps were constructed and RGC size distribution was determined.Oscillatory potentials in the group of eyes which had elevated IOP were decreased at the time of euthanasia, when IOP had returned to normal. A group of normal B-N rats had similar RGC counts between contralateral eyes. In the experimental group the mean number of RGCs was not significantly different between control and experimental eyes, but 1 of 5 Wistar and 2 of 7 B-N experimental eyes had at least 30% fewer RGCs from contralateral control eyes. Total retinal area in B-N experimental eyes was higher compared with contralateral eyes. Cumulative IOP exposure of the experimental eyes was modestly correlated with RGC loss while oscillatory potentials appeared to be inversely related to RGC loss. In retinas with extensive (>30% RGC loss) but not complete damage, smaller cells were preserved better than larger ones.The above results indicate that RGC loss in both Wistar and B-N strains is variable after a prolonged elevation of IOP via EVC. Such variability despite equivalent IOP levels and ERG abnormalities, suggests unknown factors that can protect IOP-stressed RGCs. Identification and enhancement of such factors could prove useful for glaucoma therapy.
Elevated levels of vitreal glutamate can increase the expression of GS in retinal Müller cells. This increase was blocked if IOP was acutely elevated for 24 hours but was restored if IOP remained elevated for 1 week. This finding suggests that moderate elevation of IOP causes only short-term functional changes of glutamate metabolism (amidation) by retinal Müller cells. However, it is not known to what extent endogenous extracellular glutamate can regulate GS expression in normal eyes or in eyes with glaucoma.
Objective: Clinical trials have emerged as the main force in driving the development of medicine. However, little is known about the current status of clinical trials regarding drug control and prevention of ventilator-associated pneumonia (VAP). This study aimed at providing a comprehensive landscape of these trials on the basis of ClinicalTrials.gov . Methods: A cross-sectional, descriptive study of clinical trials on drug control and prevention of VAP which have been registered on the ClinicalTrials.gov up to 25 th August 2018 was conducted. Results: A total of 109 eligible trials were identified. Trials were started from 1998 to 2018, and most trials focused on adult patients. More than half trials were completed, while only 11.9% trials had results available. Sample sizes were relatively large, with a median enrollment of 146. Universities were listed as the primary sponsor for 36.7% trials, industry for 28.4% trials and hospitals for 19.3% trials. Of the 109 VAP trials, 37 trials were from in Europe, 36 in North America and 27 in Asia. Among the 97 interventional trials, 32 were phase 3 trials, 21 were phase 4 trials, and 16 were phase 2 trials. Most interventional trials were randomized trials with a parallel assignment, and 57.7% trials were blinded. Of the 12 observational trials, 9 were cohort studies, and 10 trials were prosepctive studies. Drugs about oral care, preemptive antibiotics and probiotics were most investigated for prevention. A total of 61 trials investigated drugs for the treatment of VAP, mainly focused on antibiotics. A total of 36 kinds of antibiotics were investigated for monotherapy or combination therapy. Beta-lactams were most studied, followed by aminoglycosides and polypeptides. Conclusion: Most clinical trials registered on ClinicalTrials.gov about drugs for VAP were interventional trials with the purpose for treatment. A high proportion of interventional trials were randomized, parallel assigned and masked. Our analysis highlights the need for improvement in completeness of study results on the ClinicalTrials.gov .
PurposeA thymoma is a tumor arising from the epithelium of the thymus, mostly occurring in the anterior mediastinum. The incidence of this disease is low and research progress in this field is slow. Consequently, there is an urgent need to investigate the correlation between molecular regulation and the prediction of survival and prognosis in patients with thymoma.MethodsWe collected thymoma datasets from The Cancer Genome Atlas (TCGA). Differentially expressed genes (DEGs) of TCGA datasets were then determined using R software. A gene signature was obtained by screening prognostic DEGs from the TCGA datasets using univariate and multivariate Cox survival analysis. The summation of the weighted expression levels was calculated as a risk score, which could then be used to predict the survival rate and prognosis of patients with thymoma. The validity of this model was verified by the analysis of receiver operating characteristic (ROC) curves and area under the curve (AUC).ResultsIn total, 297 DEGs were identified from the integrated results of TCGA datasets. A seven-gene signature, along with a regression model of prognostic risk, was obtained by Cox survival analysis. The expression levels of the seven genes were then weighted and summed to calculate the risk score for each sample. Patients were effectively divided into high- and low-risk groups using the median risk score (P < 0.05). ROC analysis showed that this Cox regression model was effective in predicting the prognosis of patients with thymus tumors (AUC = 0.983, P < 0.05).ConclusionFor the first time, we identified an effective seven-gene signature in patients with thymic tumors. In the future, the risk and prognosis of patients can be preliminarily assessed using this model, although further testing is required to improve rigor.
The objective of this study was to evaluate high-density lipoprotein (HDL) antioxidative activity and its possible influencing factors in patients with essential hypertension and to investigate the correlations between HDL antioxidative activity and the carotid arterial intima-media thickness (CIMT). Thirty-three patients with essential hypertension and 32 healthy people as control were included. High- and low-density lipoprotein in plasma were isolated by one-step density gradient ultracentrifugation, and induced oxidation with external Cu(2+). Antioxidant activity of HDL, lag time, and lipid peroxidation degree were determined by spectrophotometric and thiobarbituric acid reactive substances (TBARS) methods. Paraoxonase 1 (PON1) activity in serum was measured with continuous monitoring using phenylacetate as a substrate. The CIMT was measured with a high-resolution ultrasound Doppler system. In patients with essential hypertension, the inhibitory effect of HDL on low-density lipoprotein (LDL) oxidation and the PON1 activity were reduced (72.29 +/- 2.03)% vs. (80.91 +/- 2.06)%, and (112.21 +/- 8.64)u/ml vs. (146.43 +/- 8.79)u/ml (all P < 0.05). The lag time of oxidation and the lipid peroxidation between the hypertensive group and the control group did not show a statistically significant difference. Multiple stepwise regression analysis revealed that HDL antioxidative activity might be affected by PON1 activity (P = 0.004), diastolic pressure (P = 0.004), sex (P = 0.006), and that CIMT might be affected by HDL antioxidative activity (P = 0.030), systolic pressure (P = 0.026), and total cholesterol level (P = 0.033). The HDL antioxidative activity is reduced in patients with essential hypertension and significantly affected by sex. The CIMT was negatively correlated with HDL antioxidative activity, which suggests that decreased HDL antioxidative activity may be one of the important determinants for the development of atherosclerosis in patients with essential hypertension.
Background: Numerous evidence has suggested that either hypertension or atrial fibrillation (AF) is associated with systemic inflammation. Peroxisome proliferator-activated receptor-γ (PPARγ) has been proved to have anti-inflammatory effects and is implicated as a molecular pathway involved in many cardiovascular diseases, such as hypertension. The correlation between PPARγ inflammation and AF is still unknown. Methods: Using a case-control study design, 57 patients with hypertensive AF (persistent AF: 32, paroxysmal AF: 25) were included into the study groups. A total of 32 age-matched patients with hypertension, but without AF were selected as the control group. The expressions of PPARγ, interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) mRNA in monocytes were detected by using a reverse transcription-polymerase chain reaction (RT-PCR). Interleukin-1 (IL-1) was measured by immunoenzymetric methods. Results: The PPARγ mRNA was markedly decreased in the hypertensive AF group as compared with the hypertensive non-AF group, and it was significantly lower in persistent AF than paroxysmal AF (0.222 ± 0.0702 vs 0.564 ± 0.0436, P<0.01). TNF-α mRNA, IL-6 mRNA, and IL-1 were increased in patients with hypertensive AF compared to the non-AF group and it was even higher in persistent AF than in paroxysmal AF (0.721 ± 0.0541 vs 0.530 ± 0.0496, 0.567 ± 0.044 vs 0.457 ± 0. 0505, 325.61 ± 88.10 vs 190.65 ± 59.38, respectively, P<0.01). TNF-α, IL-6, and IL-1 were in negative correlation with PPARγ, the correlation coefficient was −0.854, −0.769, and −0.702, respectively (P<0.01). Conclusions: In hypertensive patients, increased inflammatory cytokines were associated with increased incidence of AF and atrial remodeling; PPARγ may be involved in the pathogenesis of AF by regulation of inflammation.
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