Digital image technology based on PCA and SVM for detection and recognition of foreign bodies in lyophilized powder.

BACKGROUND: Digital image technology has made great progress in the field of foreign body detection and classification, which is of great help to drug purity extraction and impurity analysis and classification. OBJECTIVE: The detection and classification of foreign bodies in lyophilized powder are important. The method which can obtain a higher accuracy of recognition needs to be proposed. METHODS: We used digital image technology to detect and classify foreign bodies in lyophilized powder, and studied the process of image preprocessing, median filtering, Wiener filtering and average filtering balance to better detect and classify foreign bodies in lyophilized powder. RESULTS: Through industrial small sample data simulation, test results show that in the process of image preprocessing, 3 × 3 median filtering is best. In the aspect of foreign body recognition, the recognition based on principal component analysis (PCA) and support vector machine (SVM) algorithm and the recognition based on PCA and Third-Nearest Neighbor classification algorithm are compared and results show that the PCA+SVM algorithm is better. CONCLUSION: We demonstrated that integrating PCA and SVM to classify foreign bodies in lyophilized powder. Our proposed method is effective for the prediction of essential proteins.

Erenumab safety and efficacy in migraine: A systematic review and meta-analysis of randomized clinical trials.

BACKGROUND: Erenumab is a new medicine recently approved in the United States of America for the preventive treatment of migraine among adults. We aimed to conduct a meta-analysis and evaluation of the efficacy and safety of erenumab among patients with migraine. METHODS: The electronic databases that were searched comprised PubMed, Embase and the Cochrane library, which were independently retrieved by 2 reviewers. Only randomized controlled trials (RCTs) that compared placebo with erenumab were selected. Mean differences (MDs), pooled risk ratios (RRs), and their corresponding 95% confidence intervals (CIs) were calculated for continuous and dichotomous data, respectively. RESULTS: Five RCTs representing 2928 patients were included. Pooled analysis showed significant reductions in the 50% responder rate (RR 1.55; P < .00001; I = 49%). In addition, the mean monthly migraine days from baseline in the erenumab group compared with placebo (MD-1.32; P < .00001; I = 100%) and migraine-specific medication days) from baseline (MD-1.41; P < .00001; I = 100%) were significantly decreased for the erenumab group as compared with placebo. Furthermore, Migraine-specific medication days from baseline in the 140 mg erenumab group were significantly reduced as compared the 70 mg group (MD = 0.55; P < .00001; I = 90%). Finally, there was no significant difference between the erenumab group and placebo for any adverse event and serious adverse event. CONCLUSION: Among patients with migraine, both 70 and 140 mg of erenumab were associated with reduced Migraine-specific medication days, Migraine-specific medication days from baseline, and an increased rate of a 50% reduction, in the absence of an increased risk of any serious adverse effect.

The protective effect of caffeic acid on global cerebral ischemia-reperfusion injury in rats.

Ischemic stroke is a major cause of death and disability all over the world. Ischemic stroke results from a temporary or permanent reduction of cerebral blood flow that leads to functional and structural damage in different brain regions. Despite decades of intense research, the beneficial treatment of stroke remains limited. In light of this, the search for effective means ameliorating cerebral ischemia-reperfusion injury (CIRI) is one of the major problems of experimental medicine and biology. Recently, the 5-Lipoxygenase (5-LO, a key enzyme metabolizing arachidonic acid to produce leukotrienes) inhibitors have been showed to protect brain against ischemic damage in animal model of cerebral ischemia. Caffeic acid, an inhibitor of 5-LO, is a phenolic compound widely distributed in medicinal plants. The aim of this study was to investigate the effect of caffeic acid on global cerebral ischemia-reperfusion injury in rats. The study was carried out on 45 rats that were randomly divided into five groups: the sham group (n = 9), I/R non-treated group (n = 9), I/R-caffeic acid group (10 mg · kg(-1)) (n = 9), I/R-caffeic acid group (30 mg · kg(-1)) (n = 9) and I/R-caffeic acid group (50 mg · kg(-1)) (n = 9). Global cerebral ischemia was induced by bilateral carotid artery occlusion for 20 min followed by reperfusion. Spatial learning and memory was evaluated using Morris water maze. Histopathological changes of hippocampus neurons was observed using HE staining. Superoxide dismutase (SOD, the antioxidant enzyme) activities and malondialdehyde (MDA, an oxidative stress biomarker) contents were detected. NF-κBp65 expression was detected by the methods of immunohistochemistry. Caffeic acid markedly reduced the escape latency, relieved hippocampal neurons injury and increased neuron count compared with those of I/R non-treated rat. NF-κBp65 expression and MDA content decreased significantly, and SOD activities increased significantly in hippocampus. Compared with sham group, 5-LO expression increase significantly in I/R non-treated group rat, and caffeic acid markedly reduced 5-LO expression. The results of the study suggest that caffeic acid has a significant protective effect on global cerebral ischemia-reperfusion injury in rats. The neuroprotective effects is likely to be mediated through the inhibition of 5-LO.

Time course change of COX2-PGI2/TXA2 following global cerebral ischemia reperfusion injury in rat hippocampus.

BACKGROUND: Neuroinflammation plays pivotal roles in the progression of cerebral ischemia injury. Prostaglandins (PGs) as the major inflammatory mediators in the brain participate in the pathophysiological processes of cerebral ischemia injury. Cyclooxygenase-2 (COX2) is the rate-limiting enzyme of PGs, and thus it is necessary to characterize of the expression patterns of COX2 and its downstream products at the same time in a cerebral ischemia/reperfusion (I/R) model. METHODS: The levels of prostacyclin (PGI2) and thromboxane (TXA2) and the expression of COX2 were detected in the rat hippocampus at different time points after reperfusion (30 min, 2 h, 6 h, 24 h, 48 h, 7 d, and 15 d). RESULTS: The COX2 mRNA and protein expressions in hippocampus both remarkably increased at 30 min, and peaked at 7 d after global cerebral I/R compared with the sham-operated group. The level of PGI2 significantly increased at 2 h after reperfusion, with a peak at 48 h, but was still significantly higher than the sham-operated animals at 15 d. TXA2 level decreased at 30 min and 2 h after reperfusion, but significantly increased at 6 h and peaked at 48 h. PGI2/TXA2 ratio increased at 30 min after reperfusion, and peaked at 48 h compared with the sham-operated animals. CONCLUSIONS: I/R injury significantly increased the COX2 expression, PGI2 and TXA2 levels, and the PGI2/TXA2 ratio in rat hippocampus in a time-dependent manner. As a consequence, the increased PGI2 level and PGI2/TXA2 ratio may represent a physiological mechanism to protect the brain against the neuronal damage produced by I/R injury.

[Kinetics model for photo-catalytic degradation of Rodamine B with TiO2 /SiO2 as catalyst].

A novel photo-catalytic reactor of three-phase internal circulation fluidized bed was employed to the photodegradation of Rhodamine B with TiO2/SiO2 carried on porous silica as photocatalyst. The degradation kinetics of Rodaming B is investigated in the reactor. It is found that the degradation of Rodaming B conform hyperbola model, the reciprocal of degradation rate 1/X is proportional to the reciprocal of time 1/t. The reaction rate constant has no relation with initial reactant concentration and is proportional to the light density and volumetric rate of energy absorption. The reaction rate conforms the experiment results quite well, the average relative error being less 3.25%.

[Radiation transformation mechanism in a photocatalytic reactor of three-phase internal circulating fluidized bed].

A novel three-phase internal circulating fluidized bed photocatalytic reactor was established and the radiation transformation in which was investigated. The experimental results indicate that with the interaction of gas and solid (gas flux > 0.3m3/h), the radiation transformation in the reactor along radial direction conforms to a definite exponential function, which agrees to formula Rose about the rules of light intensity distribution through evenly suspended particles. The value of radiation energy is affected by the initial light intensity, the concentration of photocatalyst and the thickness of liquid layer. The aerated gas amount only influence the state of the fluidized bed and has little effect on the distribution of light intensity along radical direction. Photocatalytic degradation of Rhodamine B indicate that the efficiency of three-phase internal circulating fluidized bed is much higher than slurry bed. The optimal catalyst concentration of this system is 10 - 12g/L.