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Aim:

SMXZF (a combination of ginsenoside Rb1, ginsenoside Rg1, schizandrin and DT-13) derived from Chinese traditional medicine formula ShengMai preparations) is capable of alleviating cerebral ischemia-reperfusion injury in mice. In this study we used network pharmacology approach to explore the mechanisms of SMXZF in the treatment of cardio-cerebral ischemic diseases.

Methods:

Based upon the chemical predictors, such as chemical structure, pharmacological information and systems biology functional data analysis, a target-pathway interaction network was constructed to identify potential pathways and targets of SMXZF in the treatment of cardio-cerebral ischemia. Furthermore, the most related pathways were verified in TNF-α-treated human vascular endothelial EA.hy926 cells and H2O2-treated rat PC12 cells.

Results:

Three signaling pathways including the NF-κB pathway, oxidative stress pathway and cytokine network pathway were demonstrated to be the main signaling pathways. The results from the gene ontology analysis were in accordance with these signaling pathways. The target proteins were found to be associated with other diseases such as vision, renal and metabolic diseases, although they exerted therapeutic actions on cardio-cerebral ischemic diseases. Furthermore, SMXZF not only dose-dependently inhibited the phosphorylation of NF-κB, p50, p65 and IKKα/β in TNF-α-treated EA.hy926 cells, but also regulated the Nrf2/HO-1 pathway in H2O2-treated PC12 cells.

Conclusion:

NF-κB signaling pathway, oxidative stress pathway and cytokine network pathway are mainly responsible for the therapeutic actions of SMXZF against cardio-cerebral ischemic diseases.  相似文献   
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Tocainide has shown promise in the acute suppression of ventricular arrhythmias and in the treatment of such arrhythmias considered refractory to other drugs. However, there is little experience with tocainide therapy using currently acceptable statistical end points in patients not receiving conventional antiarrhythmic drugs concurrently. Accordingly, a double-blind, crossover study design was used to compare the effects of 2 week periods of placebo therapy and small dose (400 mg every 8 hours) tocainide therapy in 10 patients with ventricular arrhythmias who were not receiving quinidlne, procainamide or disopyramide. Ventricular arrhythmias were assessed with 24 hour ambulatory electrocardiographic monitoring and treadmill exercise. Individual patients not responding to small dose tocainide with at least an 80 percent decrease in ventricular premature complexes on ambulatory monitoring were given doses of 600 mg and then 800 mg every 8 hours. Small dose tocainide therapy resulted in a decrease in ventricular premature complexes/hour from 364 ± 98 (standard error) to 127 ± 50 (p < 0.05) and 5 of 10 patients had at least an 80 percent decrease. At higher dose levels, two additional patients had at least an 80 percent decrease. The response of ventricular arrhythmias during treadmill exercise was comparable with that during ambulatory monitoring. Side effects were minor or nonexistent in the seven patients who responded to tocainide, and effective mean serum concentrations were 4.4 ± 1.9 μg/ml, a value significantly lower than that previously reported to suppress refractory ventricular arrhythmias. It is concluded that tocainide is an effective agent in patients not receiving concurrent therapy with conventional agents and that patients selected because of refractory ventricular arrhythmias may require higher serum concentrations of the drug than unselected patients.  相似文献   
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To assess the value of fiberoptic bronchoscopy and transbronchial biopsy for evaluating patients suspected of having tuberculosis, we reviewed the records of 56 patients (1974–1980). All patients (1) were clinically suspected of having active tuberculosis; (2) had an abnormality on chest roentgenogram consistent with tuberculosis; (3) had an absence of acid-fast bacilli on three sputum smears or an inability to produce sputum; (4) had undergone fiberoptic bronchoscopy and transbronchial biopsy. The evaluations included fiberoptic bronchoscopy with collection of bronchial washings and brushings, and transbronchial biopsy and postbronchoscopy sputum specimens. Thirteen patients subsequently underwent percutaneous needle aspiration and one underwent thoracotomy.

Evaluations were diagnostic in 29 of the 56 patients (52 percent). Diagnoses were mycobacterial infection in 22 (39 percent) and other disease processes in seven (13 percent). Fiberoptic bronchoscopy and transbronchial biopsy provided a diagnosis when sputum cultures obtained before bronchoscopy were negative for Mycobacteria in 11 (20 percent) patients. Immediate diagnoses were made from microscopic specimens obtained from 11 of 23 (48 percent) fiberoptic bronchoscopy and transbronchial biopsy procedures on patients with previously undiagnosed mycobacterial infection. Transbronchial biopsy had the best yield for a microscopic diagnosis. On culture, bronchoscopy specimens had a lower yield (10 of 23 or 44 percent) than sputum specimens obtained before bronchoscopy (14 of 21 or 67 percent) probably due to the inhibition of mycobacterial growth by tetracaine. Of the patients in whom evaluation proved nondiagnostic, 17 of 27 were lost to follow-up; therefore, a definitive statement regarding the number of false negative evaluations is not possible.

Fiberoptic bronchoscopy and transbronchial biopsy (FFB/TBB) is a useful procedure in evaluating patients with negative smears who are clinically suspected of having tuberculosis. It can improve the ability to document active tuberculosis, provide a sensitive means of making an immediate diagnosis, and uncover other disease processes presenting like tuberculosis.  相似文献   

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《Vaccine》2015,33(28):3200-3207
PurposeIn April 2007, Panama introduced Hepatitis A universal vaccination using a two-dose schedule (Havrix® junior; GSK Vaccines, Belgium). We assessed the impact of this hepatitis A vaccine three years after it was recommended for universal mass vaccination in Panama.Materials and methodsHepatitis A vaccination impact was assessed using two different approaches. The first approach used retrospective data (incidence and number of cases for all age groups), collected from the passive surveillance of the Epidemiologic Surveillance System of the Ministry of Health of hepatitis A and unspecified hepatitis before (2000–2006) and after (2008–2010) introduction of hepatitis A vaccine. The second approach was a prospective hospital-based active surveillance for hepatitis cases conducted in subjects (0–14years) during 2009–2011 at three sentinel hospitals in Panama.ResultsOverall, the annual incidence of hepatitis A and unspecified hepatitis in 2008, 2009 and 2010 were 13.1, 7.9 and 3.7 per 100,000 subjects, lower than the baseline incidence of 51.1 per 100,000 subjects. In comparison to the mean baseline period (2000–2006), there was an 82% mean reduction in the overall hepatitis-related outcomes (hepatitis A and unspecified hepatitis) after vaccine introduction (2008–2010) in all age groups.In the hospital-based surveillance (2009–2011), of the 42 probable viral hepatitis A cases, nine cases were confirmed as acute hepatitis A (8 in 2009, 1 in 2010). Of these confirmed cases, two belonged to the targeted vaccine group (1–4 years) but were not vaccinated.ConclusionsOur study suggests that the introduction of two-dose hepatitis A vaccines in Panama has contributed to the reduction in the incidence of overall hepatitis-related outcomes for all age groups, suggesting herd protection. Additional monitoring is required to document a sustained long-term effect.  相似文献   
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Although propranolol is frequently utilized as therapy for angina pectoris in patients with previous myocardial infarction, its effects on wall motion abnormalities in such patients have not been adequately defined. Accordingly, using external wall motion video tracking, we studied 18 patients with previous myocardial infarction and wall motion disorders and 5 normal subjects before and after administration of propranolol, 5 mg intravenously. Systolic time intervals, heart rate and left heart size (measured by the distance between the mid-line and left heart border in an X-ray film triggered at end-diastole after a standard inspiration) were also measured before and after administration of propranolol. In each instance propranolol produced a reduction in the amplitude and velocity of wall motion in areas of normal movement, hypokinesis and paradox, resulting in decreased outward bulging. In the normal subjects, the amplitude and velocity of wall motion also decreased. In the patients with previous myocardial infarction, propranolol increased the ratio of the preejection period to the left ventricular ejection time from a mean of 0.377 ± 0.03 (standard error of the mean) to 0.409 ± 0.03 (P <0.001); decreased heart rate by an average of 7.5 beats/min (P <0.001); and increased the distance from the mid-line to the left heart border from 94.3 ± 2.6 to 97.3 ± 2.6 mm (P <0.001). Similar changes occurred in the 5 normal subjects. We conclude that doses of propranolol sufficient to increase the ratio of the preejection period to left ventricular ejection time, decrease heart rate and increase heart size do not exaggerate preexisting paradoxical wall motion or accentuate latent areas of paradox in patients with previous myocardial infarction.  相似文献   
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