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Background: The oomycete fungicide flumorph is a recently introduced carboxylic acid amide (CAA) fungicide. In order to evaluate the risk of developing field resistance to flumorph, the authors compared it with dimethomorph and azoxystrobin with respect to the ease of obtaining resistant isolates to these fungicides, the level of resistance and their fitness in the laboratory., Results: Mutants with a high level of resistance to azoxystrobin were isolated readily by adaptation and UV irradiation, and their fitness was as good as that of the parent isolates. Attempts to generate mutants of Pseudoperonospora cubensis (Burk. & MA Curtis) Rostovsev resistant to flumorph and dimethomorph by sporangia adaptation on fungicide-treated leaves were unsuccessful. However, moderately resistant mutants were isolated using UV mutagenesis, but their resistance level [maximum resistance factor (MRF) < 100] was much lower than that of the azoxystrobin-resistant mutant (MRF = 733). With the exception of stability of resistance, all mutants showed low pathogenicity and sporulation compared with wild-type isolates and azoxystrobin-resistant mutants. There is cross-resistance between flumorph and dimethomorph, suggesting that they have the same resistance mechanism., Conclusion: The above results suggest that the resistance risk of flumorph may be similar to that of dimethomorph but lower than that of azoxystrobin and can be classified as moderate. Thus, it can be managed by appropriate product use strategies., ((c) 2007 Society of Chemical Industry.)

ABSTRACT The mechanism of the effects of flumorph (a novel fungicide) was investigated by analyzing alterations of hyphal morphology, cell wall deposition patterns, F-actin organization, and other organelles in Phytophthora melonis. Calcofluor white staining suggested that flumorph did not inhibit the synthesis of cell wall materials, but disturbed the polar deposition of newly synthesized cell wall materials during cystospore germination and hyphal growth. After exposure to flumorph, zoospores were able to switch into cystospores accompanied with the formation of a cell wall, whereas cystospores failed to induce the isotropic-polar switch and did not produce germ tubes but continued the isotropic growth phase. In flumorph-treated hyphae, the most characteristic change was the development of periodic swelling ("beaded" morphology) and the disruption of tip growth. Newly synthesized cell wall materials were deposited uniformly throughout the diffuse expanded region of hyphae, in contrast to their normal polarized patterns of deposition. These alterations were the result of F-actin disruption, identified with the fluorescein isothiocynate (FITC)-phalloidin staining. The disruption of F-actin also was accompanied by disorganized organelles: each swelling of subapical hyphae was associated with a nucleus. Vesicles did not undergo polarized secretion to the apical hyphae, but diffused around nuclei for the subapical growth; thus, the cell wall was thickened with periodic expansion along the hyphae. Upon removing flumorph, normal tip growth and organized F-actin were observed again. These data, as well as data published earlier, suggest that flumorph may be involved in the impairment of cell polar growth through directly or indirectly disrupting the organization of F-actin. The primary site of action by flumorph in the disruption of the F-actin organization is under investigation.

Objective: To determine the optimum technical parameters through controlling the different factors and the content of Dripping Pill., Method: Time of dissolution, spherical degree and pill weight as parameters, the influential factors were investigated by orthogonal test and then to determine the content of liensinine, isoliensinine, neferine in plumula nelumbinis Alkaloid Dripping Pill., Result: The optimum condition: 75% PEG4000 as matrix, methyl-silicon oil as refrigerant, 4 cm dripping distance, 10 degrees C refrigerant, 30 drippings per minute., Conclusion: The good quality pills can be produced through this process and the HPLC determination method is simple, reliable and can be used in the quality control of plumula nelumbinis Alkaloid Dripping Pill.

Objective: To compare the solubilities of ephedrine and d-pseudo-ephdrine in the compound of traditional Chinese drugs--Maxing Shigan decoction with and without ultramicro-pulverizations using a RP-HPLC procedure., Method: The analytical column was a YMC ODS-C18(4.6 mm x 150 mm,4 microm). A mixture of water-acetonitrile-sodium dodecyl sulfate-phosphorous acid (650:350:5:1) was used as the mobile phase at flow rate of 1.5 mL x min(-1). The column temperature was 50 degrees C and the wavelength was 210 nm., Result: In this way, ephedrine and d-pseudo-ephedrine of the compound samples can be separated well and showed significant differences before and after the ultramicro-pulverizations., Conclusion: For the Maxing Shigan decoction, the dissolution rates and solubilites of ephedrine and d-pseudo-ephedrine ultramicro-pulverization were greatly improved.

Aim: To observe the antagonistic effect of hydroxysafflor yellow A (HSYA) on the platelet activating factor (PAF)., Methods: Washed rabbit platelet (WRP) aggregation and rabbit polymorphonuclear leukocytes (PMNs) aggregation induced by PAF were observed by turbidimetric assay in vitro. The PAF receptor antagonistic effect of HSYA was investigated by radio ligand binding assay (RLBA)., Results: In RLBA the specific binding inhibition effect of HSYA was found to be concentration-dependent in three different [3H]PAF concentrations. In the experiments, WRP aggregation and rabbit PMNs aggregation induced by PAF (9.55 x 10(-10), 9.55 x 10(-6) mol.L-1) were both inhibited by HSYA in a concentration-dependent manner in vitro. The IC50 of HSYA to inhibit WRP and rabbit PMNs aggregation was 0.99 and 0.70 mmol.L-1, respectively., Conclusion: The PAF receptor binding can be antagonized by HSYA.

We carried out a randomized, placebo-controlled, double-blinded trial to evaluate the effect on morbidity of high dose oral vitamin A, given on hospital admission to 592 children aged 1-59 months with moderate and severe pneumonia. Severely underweight children were not included, but 45% were moderately underweight. The vitamin A and placebo groups were comparable in baseline characteristics. Four patients died. Among all of the surviving children, no differences were found regarding mean time for normalization of fever, respiratory rate and time of hospitalization. Stratification for moderate malnutrition, degree of pneumonia, age and sex revealed moderately malnourished vitamin A-supplemented children to have a shorter time of hospitalization (p = 0.04), due to an effect in females aged > 12 months (p = 0.02) and females with very severe pneumonia (p = 0.048). This study indicates that, in developing countries like Vietnam, supplementation with vitamin A in children with pneumonia could shorten the recovery rate in the ones that are undernourished, especially females > 1 y old.

Interferon alpha has confirmed its efficacy for the therapy of chronic hepatitis C. Half of the patients treated will normalize their plasma ALT at the end of a 6-month course of 3 MU thrice a week. This biochemical response is associated with a reduction of HCV RNA (viraemia) from serum and with significant improvement of liver histology. Despite those beneficial effects, 50% of treatment responders generally relapse after treatment arrest. Increasing doses to 6 MU and/or the duration of interferon therapy increases the proportion of long-term sustained responders. Combining therapy with ribavirin, a nucleoside analogue, also appears to have a similar effect.