Polygodial, the fungitoxic component from the Brazilian medicinal plant Polygonum punctatum. (1/46)

Polygonum punctatum (Polygonaceae) is an herb known in some regions of Brazil as "erva-de-bicho" and is used to treat intestinal disorders. The dichloromethane extract of the aerial parts of this plant showed strong activity in a bioautographic assay with the fungus Cladosporium sphaerospermum. The bioassay-guided chemical fractionation of this extract afforded the sesquiterpene dialdehyde polygodial as the active constituent. The presence of this compound with antibiotic, anti-inflammatory and anti-hyperalgesic properties in "erva-de-bicho" may account for the effects attributed by folk medicine to this plant species.  (+info)

Constituents from Polygonum cuspidatum. (2/46)

Two lignan sulfates, a stilbene derivative and a phenol sulfate, together with 10 known compounds, were isolated from an aqueous extract of the root of Polygonum cuspidatum. The new compounds were elucidated based on chemical evidence and spectroscopic techniques including two-dimensional NMR methods. They exhibited no inhibition of lipid peroxidation and no cytotoxic and DNA cleavage activities.  (+info)

Barriers to sexual reproduction in Polygonum viviparum: a comparative developmental analysis of P. viviparum and P. bistortoides. (3/46)

Polygonum viviparum is widely distributed in arctic and alpine regions of the northern hemisphere. Fruit set has never been observed in North American populations and has been reported only very rarely in Europe. Although this species is extremely well studied, the impediments to successful fruit production are unknown. We investigated the sexual reproductive process in P. viviparum growing in the southern Colorado Rocky Mountains. For comparison, we also examined this process in the sympatric congener P. bistortoides, in which reproduction is exclusively sexual. Lack of viable fruit production in P. viviparum has no single developmental explanation; defects occur in each of the processes and structures associated with sexual reproduction studied, yet, these processes and structures also appear to function normally in at least some flowers or individuals. Development is abnormal in many ovules of P. viviparum, however, comparison with P. bistortoides shows that these abnormalities do not contribute to differences in seed production between the two species. The virtual absence of sexual reproduction in P. viviparum appears to be due largely to a low rate of fertilization and to embryo/fruit abortion.  (+info)

Comparative study on the free flavonoid aglycones in herbs of different species of Polygonum L. (4/46)

The flavonoid aglycones were studied in the herbs of the following taxons of the Polygonum L. genus: P. hydropiper L, P. bistorta L., P. aviculare L., P. persicaria L., P. lapathifolium ssp. tomentosum (Schrank) Dans, P. lapathifolium ssp. nodosum (Pers.) Dans, P. amphibium L., P. mite Schrank, P. conolvulus L. (Bilderdykia convolvulus L.) by means of the RP-HPLC method. The content of taxifolin, quercetin, quercetin-3-methyl ether, kaempferol, myritcetin, luteolin, isorhamnetin and rhamnetin were determined.  (+info)

Increase in leaf mass per area benefits plant growth at elevated CO2 concentration. (5/46)

An increase in leaf mass per area (MLA) of plants grown at elevated [CO2] is often accompanied by accumulation of non-structural carbohydrates, and has been considered to be a response resulting from source-sink imbalance. We hypothesized that the increase in MLA benefits plants by increasing the net assimilation rate through maintaining a high leaf nitrogen content per area (NLA). To test this hypothesis, Polygonum cuspidatum was grown at ambient (370 micro mol mol-1) and elevated (700 micro mol mol-1) [CO2] with three levels of N supply. Elevated [CO2] significantly increased MLA with smaller effects on NLA and leaf mass ratio (fLM). The effect of change in MLA on plant growth was investigated by the sensitivity analysis: MLA values observed at ambient and elevated [CO2] were substituted into a steady-state growth model to calculate the relative growth rate (R). At ambient [CO2], substitution of a high MLA (observed at elevated [CO2]) did not increase R, compared with R for a low MLA (observed at ambient [CO2]), whereas at elevated [CO2] the high MLA always increased R compared with R at the low MLA. These results suggest that the increase in MLA contributes to growth enhancement under elevated [CO2]. The optimal combination of fLM and MLA to maximize R was determined for different [CO2] and N availabilities. The optimal fLM was nearly constant, while the optimal MLA increased at elevated [CO2], and decreased at higher N availabilities. The changes in fLM of actual plants may compensate for the limited plasticity of MLA.  (+info)

Efficacy of Prostant on chronic prostatitis in 119 patients. (6/46)

AIM: To evaluate the efficacy and safety of Prostant in the treatment of chronic prostatitis. METHODS: One hundred and nineteen cases of patients who had been diagnosed of chronic prostatitis were treated by Prostant. The efficacy was evaluated by WBC in EPS and NIH Chronic Prostatitis Symptom Index after a one-month follow-up. RESULTS: After the one-month follow-up, the total improvement rate is 65.5 %, the WBC in the prostatic fluid were reduced from (21+/-20) to (12+/-13)/High-power field (HPF); the symptom index score changed from 12+/-4 to 7+/-5. The pain and voiding score of the symptom index were lowered from 8+/-3 to 5+/-3 and 3.9+/-2.7 to 2.3+/-2.3 respectively. All of above showed great statistic differences (P<0.05). Only 2 cases (1.7 %) reported serious diarrhea. CONCLUSION: The Prostant is effective and safe in the treatment of chronic prostatitis, especially on those cases whose symptom and inflammation in prostatic fluid are not too serious.  (+info)

Micropropagation of Polygonum multiflorum THUNB and quantitative analysis of the anthraquinones emodin and physcion formed in in vitro propagated shoots and plants. (7/46)

An efficient and rapid protocol for in vitro induction and complete plant regeneration of Polygonum multiflorum THUNB has been developed. Nodal explants were grown in vitro on Murashige and Skoog's (MS) basal medium containing different concentrations of alpha-naphthaleneacetic acid (NAA) and benzyladenine (BA). The nodal explants (97%) produced multiple shoots (4.7 shoots per explant) on MS basal medium supplemented with 0.2 mg/l NAA and 2.0 mg/l BA after 6 weeks of culture. Eighty-eight percent to 100% of the shoots (1.0 cm in length) elongated (about 3.02-4.28 cm) and rooted on MS basal medium supplemented with NAA or indole-3-butyric acid (IBA). All the rooted shoots were transferred to pots containing autoclaved soil, vermiculite, and peat moss (1 : 1 : 1). The plantlets were successfully acclimatized under greenhouse conditions with high humidity before transferring to the field. The anthraquinone contents were determined using HPLC. Analysis revealed that the contents of the major medicinal compounds-emodin and physcion in the 6 weeks old in vitro grown shoots and three month old in vitro propagated plants grown in greenhouse were higher than those of the marketed crude drug (processed underground or stem parts of P. multiflorum).  (+info)

Bond durability of resin cements to Au-Pd-Ag alloy under cyclic impact load. (8/46)

The bond durability of resin cements to a 12% Au-Pd-Ag alloy was studied through cyclic impact tests with different loads. A piece of casting alloy was bonded to a cast block with two types of resin cements, Super Bond C&B and Bistite II. A shear load was applied onto a small piece of alloy until debonding of the specimen, using different weights of plungers, 130 g, 230 g, 330 g and 430 g. The specimen bonded with Super Bond exhibited a higher resistance than that with Bistite II. The fracture modes of the debonded cements were completely different from each other. That is, Bistite II showed a bulk fracture of cement by the crack penetrating through the cement layer. On the other hand, Super Bond showed damages limited to the surface and no bulk fracture. The mode of fracture was dependent not on the loading weight but the types of resin cements used.  (+info)