Distribution of Baseline Sensitivities to Natural Product Physcion Among Isolates of Sphaerotheca fuliginea and Pseudoperonospora cubensis

The ethanol extract from rhubarb was commercialized in China (Veguard, Physcion, 5 g/liter AS) for control of cucumber powdery mildew (Sphaerotheca fuliginea) and cucumber downy mildew (Pseudoperonospora cubensis). To provide the basic data for the risk assessment of resistance to this product, physcion was selected to represent the active ingredients to establish baseline sensitivity of powdery mildew and downy mildew populations. For powdery mildew, 262 isolates of S. fuliginea from nine regions and, for downy mildew populations, 116 isolates of P. cubensis from six regions were collected in China during 2004 and 2005 and tested for sensitivity. In addition, the sensitivity of a powdery mildew isolate was monitored for 15 asexual generations under selection pressure with physcion. The results showed that there was no significant difference among regions in the frequency distribution of baseline sensitivity to this ingredient for either cucumber powdery mildew isolates or cucumber downy mildew isolates. Baseline sensitivity was distributed as a normal unimodal curve with a mean median (50%) effective concentration (EC₅₀) of 0.304 μg/ml for powdery mildew population and mean EC₅₀ of 0.501 μg/ml for downy mildew population. The variation of sensitivity to physcion was low because the range factor (maximum EC₅₀/minimum EC₅₀ of isolates within population) varied from 1.63 to 3.42 among powdery mildew populations and from 1.70 to 2.38 among downy mildew populations. The powdery mildew isolate XZ4 did not decrease sensitivity under the selection pressure of physcion at the dose of EC₇₀ for 15 generations.

[Long-term clinical observation after repair of ruptured Achilles tendon (with 62 cases report)]

OBJECTIVE

To investigate the clinical result and influence factors of prognosis after repair of ruptured Achilles tendon with operative treatment.

METHODS

From 1961 to 1994, 62 cases with ruptured Achilles tendon were treated operatively. Among them, "8"-shaped suture was used in 8 cases, aponeurosis flap repair in 30 cases, transfer repair of tendon of peroneus longus muscle in 2 cases, reverse "V-Y" shaped tendon plastic operation in 10 cases, and mattress suture of opposite ends in 12 cases.

RESULTS

Followed up 3 to 33 years, there was excellent in 40 cases, better in 13 cases, moderate in 6 cases, poor in 3 cases, 85.5% in excellent rate. Postoperative infection and re-rupture were occurred in 6 cases respectively.

CONCLUSION

Different operative procedures are adopted to achieve better long-term clinical result according to the injury types.

Epidemic hemorrhagic fever. The mechanism of coagulation and fibrinolysis

To understand the mechanism of hemorrhage, coagulation and fibrinolysis in epidemic hemorrhagic fever (EHF), thrombin time (TT), prothrombin time (PT), fibrinogen (FIG), the platelet count (PLAT), plasminogen (PLG), antithrombin-III (AT-III), fibrin-fibrinogen degraded products (FDP) and platelet functions of aggregation and release were studied dynamically with advanced methods in 134 EHF patients. TT and PT were prolonged, FIG, AT-III and PLG were decreased and FDP was increased. Besides, the decrease of PLAT, the platelet functions of aggregation and release were below the normal level. The results showed that the balance of blood coagulation and fibrinolysis was lost from the early stage of the disease.