[Effects of Viscum coloratum flavonoids on fast response action potentials of hearts]

The effects of the total flavonoids of Viscum coloratum (VCF) on the fast response action potentials (FAP) of canine Purkinje fibers and guinea pig ventricular papillary muscles were studied by glass-microelectrode technique. The effects of VCF on the ionic currents through cellular membrane were analysed with selective ion blockers (CsCl, verapamil, and TEA+), respectively. VCF (100 micrograms.ml-1) accelerated the repolarization of FAP and increased delta ERP/delta APD ratio, which were related to decreasing Isi and increasing Ix. It was suggested that the anti-tachyarrhythmic mechanism of VCF was attributed to prolonging ERP relatively and to abolishing reentrant excitation.

[A study of left ventricular function in normal persons and patients with old myocardial infarction with three dimensional echocardiography (3-DE)]

The accuracy of 3-DE in evaluating the volumes of left ventricule (LV) and volume changes in cardiac cycle was discussed. The LV volumes measured with 3-DE in porcine hearts is more closely to the real volumes directly measured (P > 0.05 r = 0.93). The EF value measured with radionuclide has higher correlation with that of 3-DE (r = 0.88) in patients. In a quantitative analysis of LV volume changes in cardiac cycles, we found that the decrease of EF in patients with old myocardial infarction (OMI) occurs mainly at the early stage and lasts to middle stage of systole in anterior myocardial infarction. Dysfunction of filling in OMI took place at the early and middle stages of diostole. Segmental shortening of LV was analysed quantitatively by percentage and pseudocolour mark. The reference values of 3DE in cardiac function were shown.

Epithelioid sarcoma of the penis

A rare case of penile epithelioid sarcoma in a 26-year-old white man is presented. The patient had a firm, slow growing, painless mass associated with penile deviation on erection, which was initially misdiagnosed as Peyronie's disease 5 years previously. With the onset of decreased urinary stream the lesion was biopsied, with a resultant diagnosis of epithelioid sarcoma. The patient underwent radical penectomy and perineal urethrostomy, and received 6,000 cGy. external beam radiotherapy postoperatively. Two years postoperatively the patient remained free of clinical disease. We review the pathophysiology, clinical characteristics and treatment of penile epithelioid sarcoma.

Adenosine triphosphate liposomes: encapsulation and distribution studies

Four methods for encapsulating adenosine triphosphate (ATP) in liposomes were evaluated. Optimum entrapment required emulsifying ATP with the lipids used to form the liposome membrane in a high-speed homogenizer followed by evaporating the organic solvent with vigorous stirring. Under these optimum conditions ATP entrapment was 38.9%; i.e., the dosage form contained 38.9 g of ATP per 100 g of lipid. The distribution of positively charged liposomes loaded with ATP was studied in dogs with experimentally induced myocardial infarction. Intravenous injection of positively charged ATP liposomes caused accumulation of ATP in myocardial infarct tissue. Myocardial infarct tissue has reduced blood flow; since positively charged liposomes accumulated in infarct tissue, liposomes may be a drug delivery system for this disease state.

[Factors affecting parameters of left ventricular diastolic function derived from Doppler echocardiography]

According to the data from left ventricular catheterization as well as M-mode and two-dimensional echocardiography in 36 patients, the influence of left ventricular diameter, systolic function, systolic and diastolic filling pressures on the parameters of left ventricular diastolic function derived from Doppler echocardiography was analysed. The results indicate: (1) the left ventricular end diastolic pressure, rapid filling wave pressure and the ratio of the both significantly affect the Doppler diastolic function parameters; (2) the decrease of the ratio of early-to-late diastolic mitral flow velocities (E/A) is only a manifestation of early stage of left ventricular diastolic dysfunction and the E/A ratio returns to normal (false improving) at advanced stage of left ventricular diastolic dysfunction.

[Influence of acute respiratory failure on plasma renin activity and plasma angiotensin II level in advanced chronic obstructive pulmonary disease and chronic cor pulmonale]

Plasma renin activity (PRA) and plasma angiotensin II (PAT II) level were determined with the method of radioimmunoassay in 55 patients with advanced chronic obstructive pulmonary disease (COPD) and chronic cor pulmonale (41 of them had respiratory failure) and 12 healthy aged persons. The results showed that PRA and PAT II levels were significantly elevated in the presence of such factors as severe hypoxia and hypercapnia (PaO2 less than or equal to 45 mmHg, mean 40 mmHg, PaCO2 greater than or equal to 65 mmHg), right heart failure, acidosis, hyponatremia and hypochloremia. It is shown that the prognosis would be poor when the patient's PRA level is significantly elevated.

Validation of a coronary prognostic index for the Chinese--a tale of three cities

In order to confirm the efficacy of a new coronary prognostic index for the prediction of mortality of acute myocardial infarction in the Chinese in general, this index was applied to 886 patients from six general hospitals in Hong Kong (435 patients), Guangzhou (212 patients) and Shanghai (239 patients), respectively. They could be successfully stratified into seven clinical subsets with stepwise increasing mortality. The overall mortality tallied with that predicted by the original coronary prognostic index. The efficacy of this prognostic index for the prediction of mortality from acute myocardial infarction among the Chinese is verified and its application in the objective assessment of patients with acute myocardial infarction is recommended.

[Catheter ablation in eight patients with Wolff-Parkinson-White syndrome]

After a follow-up study of 13-39 months, the clinical effect of catheter ablation in 8 patients with WPW syndrome and recurrence of SVT was reported. Five cases of left free-wall accessory pathway underwent catheter ablation attempts by direct current shocks delivered in coronary sinus. 3 of them were free from SVT without any medications after ablation, 1 case was improved. The other one was unsuccessful. Catheter ablation was attempted by delivery of shocks at coronary sinus orifice in 3 patients with posteroseptal accessory pathway. Arrhythmias were controlled without the need of drug therapy in 2 cases and the clinical symptoms were relieved in 1 case after shocks. We consider that the catheter ablation attempted to block the conduction of left free-wall and posteroseptal accessory pathway induces much less damages than surgical ablation and offers the advantages of shorter hospitalization, lower cost and a much shorter convalescence. The authors stated that it is a viable alternative to surgical ablation for those patients who are not responsive or allergic to drugs or those who are not willing to take a life-long period of medications. Some concerns for increasing the success rate and reducing the complications of ablation were also discussed.

Low-cost frequency-stabilized CO(2) laser using 4.3-microm saturated fluorescence

A frequency-stabilized CO(2) laser using the saturated fluorescence technique was constructed. Stainless-steel rods were used to support the cavity, and a thermoelectrically cooled PbSe detector monitored the 4.3-microm fluorescence from a low-pressure CO(2) absorption cell. Stabilization of the CO(2) laser at the center of the saturation dip was achieved with the absorption cell inside or outside the laser cavity. The frequency stability is estimated to be better than 3.5 x 10(-9).