Detection of ischemic wall dysfunction: Comparison between M-mode echocardiography and sonomicrometry

The quantification of regional ventricular function by M-mode echocardiography was compared to that by sonomicrometry in 10 closed-chest, sedated swine during temporary occlusions of the left circumflex coronary artery. Wall thickening during systole (%WT) was calculated to quantitate regional myocardial function, and percentage of fractional shortening (%FS) was calculated from both sonomicrometer tracings and M-mode echocardiograms. Ventricular dimensions at end diastole and end systole were also compared before and after 2 minutes of coronary artery occlusion. Both techniques detected significant changes in wall thickness, %WT, and %FS after occlusion. Changes in %WT during coronary artery occlusion detected by M-mode echocardiography and sonomicrometry had a significant linear relationship (p < 0.05). Discrepancy between the two techniques in the measurement of wall thickness at end diastole was attributed to the difficulty in measuring relatively small distances with M-mode echocardiograms. However, we conclude that the clinical M-mode echocardiogram is capable of detecting acute regional wall dysfunction associated with ischemia.     

Spurious scintiphotographic recurrence of pulmonary emboli

Pulmonary perfusion scintiphotographs in patients with acute, extensive pulmonary embolism have disclosed instances in which Scintiphotographic changes thought to indicate embolic recurrence were not substantiated by clinical-angiographic observations. These spurious Scintiphotographic recurrences reflected changes in the regional distribution of pulmonary vascular resistance secondary to different rates of embolic resolution or distal migration of emboli. To document the influence of changes in vascular resistance upon perfusion scintiphotographs, studies were performed in animals subjected to various sequences of pulmonary arterial obstruction by balloon catheters. Scintiphotographic changes mimicking, but not representing, recurrence of embolism were produced. Observations in both animals and man indicate that the diagnosis of embolic recurrence based on Scintiphotographic changes alone should be made with caution, particularly in patients with multiple emboli and pulmonary hypertension.     

五味余甘子散对大鼠心肌缺血再灌损伤的保护作用

目的探讨藏方五味余甘子散对心肌缺血再灌损伤大鼠的保护作用。方法将96只SD大鼠随机均分成五味余甘子散高、中、低剂量组及伪手术组、模型组和阳性对照组,连续给药10 d,在末次给药24 h后,进行造模,结扎左冠前室间支30min,复灌40 min。测定血清中乳酸脱氢酶(LDH)、肌酸激酶(CK)的含量及心肌组织中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)的活性和丙二醛(MDA)的含量,并比较各组心肌的超微结构变化。结果五味余甘子散能显著降低血清中LDH和CK的含量,同时能提高心肌组织中SOD、GSH-Px的活性,降低MDA的活性。结论五味余甘子散对大鼠心肌缺血再灌损伤有保护作用,其机制可能与抑制自由基相关酶有关。     

An integrated pathway interaction network for the combination of four effective compounds from ShengMai preparations in the treatment of cardio-cerebral ischemic diseases

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.     

Tocainide therapy for treatment of ventricular arrhythmias: assessment with ambulatory electrocardiographic monitoring and treadmill exercise

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.     

Bronchoscopy and transbronchial biopsy in evaluation of patients with suspected active tuberculosis

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.