Chemotaxonomic Approach to the Central Balkan Sedum Species Based on Distribution of Triterpenoids in Their Epicuticular Waxes.

Triterpenoid distribution in epicuticular waxes of 20 central Balkan Sedum L. species and four out-groups of genera: Hylotelephium H. Ohba, Crassula L., Echeveria DC., and Kalanchoe Adans. were investigated for chemotaxonomic purposes. Identification and quantification of wax triterpenoids were performed by GC/MS and GC-FID analyses. Distribution of identified triterpenoids (oleanane, lupane, and taraxerane series), as a pattern in statistical analysis, indicated very good agreement with phylogeny and systematics, except members of series Rupestria Berger, in which case the distribution of triterpenoids did not support known classification in a satisfactory manner. According to the obtained clustering, Kalanchoe is shown as similar to Sedum samples, while the other out-groups were clearly separated.

Computed tomography findings of hepatic veno-occlusive disease caused by Sedum aizoon with histopathological correlation

This study investigated the value of computed tomography (CT) in the diagnosis and treatment of hepatic veno-occlusive disease (HVOD) caused by Sedum aizoon (SA). The clinical manifestations, treatment results, imaging findings, and histological findings of the liver were analyzed in 39 patients with HVOD caused by SA. Hepatomegaly, liver dysfunction, abdominal effusion, and geographic density changes on liver CT scans were found in all 39 patients. The pathological findings of histological liver examination included swelling and point-like necrosis of liver cells, significant expansion and congestion of the sinuses, endothelial swelling, and wall thickening with incomplete lumen occlusion of small liver vessels. CT geographic density changes were confirmed by histological examination of the liver in 18 patients. Sixteen patients with small amounts of ascites that started within 4 weeks of treatment recovered completely or significantly improved after symptomatic and supportive treatment. However, only 43.75% of the patients with larger amounts of ascites improved following symptomatic and supportive treatment. In conclusion, liver CT examination is a valuable, safe, and noninvasive tool for the diagnosis of HVOD caused by SA. In selected cases, liver CT examination may replace liver biopsy and histological analysis.

Computed tomography findings of hepatic veno-occlusive disease caused by Sedum aizoon with histopathological correlation.

This study investigated the value of computed tomography (CT) in the diagnosis and treatment of hepatic veno-occlusive disease (HVOD) caused by Sedum aizoon (SA). The clinical manifestations, treatment results, imaging findings, and histological findings of the liver were analyzed in 39 patients with HVOD caused by SA. Hepatomegaly, liver dysfunction, abdominal effusion, and geographic density changes on liver CT scans were found in all 39 patients. The pathological findings of histological liver examination included swelling and point-like necrosis of liver cells, significant expansion and congestion of the sinuses, endothelial swelling, and wall thickening with incomplete lumen occlusion of small liver vessels. CT geographic density changes were confirmed by histological examination of the liver in 18 patients. Sixteen patients with small amounts of ascites that started within 4 weeks of treatment recovered completely or significantly improved after symptomatic and supportive treatment. However, only 43.75% of the patients with larger amounts of ascites improved following symptomatic and supportive treatment. In conclusion, liver CT examination is a valuable, safe, and noninvasive tool for the diagnosis of HVOD caused by SA. In selected cases, liver CT examination may replace liver biopsy and histological analysis.

[HPLC characteristic fingerprints of sedi linearis herba and sedi herba].

OBJECTIVE: To study HPLC characteristic fingerprint of Sedum lineare from different harvest periods, and to compare with its related species Sedum sarmentosum. METHODS: The HPLC fingerprints of Sedum lineare from different collecting periods were established and compared with Sedum sarmentosum by the same detection method. RESULTS: Hyperin, isoquercitrin and astragaloside were identified from the HPLC fingerprint of Sedum lineare. The fingerprint of Sedum lineare growing in the same area but different environment were basically identical; while there were remarkable differences of Sedum lineare growing in the same place but from different harvest periods, with the area of most common peaks changing from little to great, and slightly different peak number. The HPLC fingerprint of the two Sedum species had four common peaks, but could be distinguished from each other. The optimal harvest period of these two species should be full-bloom stage. CONCLUSION: The established method can provide reference for identification and quality analysis of Sedum lineare.

Comparative genetic structure between Sedum ussuriense and S. kamtschaticum (Crassulaceae), two stonecrops co-occurring on rocky cliffs.

• Premise of the study: Geographic isolation due to discontinuities of suitable habitat may have significant effects on the genetic structure of plant populations. Even within a few kilometers, physical barriers to gene flow may lead to considerable genetic differentiation among populations.• Methods: Sedum ussuriense is a boreal species that in Korea occurs only in four valleys separated by mountain ranges in Juwangsan National Park and its vicinity (a range of ∼15 km). Its congener S. kamtschaticum, by contrast, co-occurs in the four valleys but also on the intervening mountains. Using 12 allozyme loci, we comparatively assessed genetic variability and structure in 12 population pairs of the two stonecrops.• Key results: While we found high and comparable levels of within-population genetic variation for the two species, among-population divergence was significantly higher in S. ussuriense (FST = 0.261 vs. FST = 0.165). Sedum ussuriense also showed a much higher percentage of among-valley variation (19%) than S. kamtschaticum (4%).• Conclusions: High levels of genetic diversity in the two Sedum species are consistent with the previous hypothesis that mountains of the Korean Peninsula served as glacial refugia for many boreal species. Given that the two congeners have similar life-history traits, the lower among-population differentiation in S. kamtschaticum is attributable to its higher abundance and more continuous distribution in the study area. This study confirms the central role of geographic isolation in the genetic structure of plant species even at very small scales.

[AS-PCR amplification in identification of Sedum sarmentosum with its relative species].

OBJECTIVE: To develop a scientific and effective method for identification of Sedum sarmentosum and its relative materials easily confused. METHODS: DNA templates were extracted from plants, and DNA fragments of cpDNA trnL (tRNA-Leu) gene and trnL-trnF intergenic spacer were amplified and sequenced subsequently. trnL-trnF sequences of all samples were aligned. RESULTS: The allele specific PCR method was studied with the designed allele-specific for distinguishing different samples. The result indicated that 300 bp and 500 bp DNA fragments were amplified from Sedum sarmentosum, where no any fragment was amplified from its relative species under the same reaction condition. CONCLUSION: The primers designed in this study are specific for Sedum sarmentosum from its relative species.

Non-invasive microelectrode cadmium flux measurements reveal the spatial characteristics and real-time kinetics of cadmium transport in hyperaccumulator and nonhyperaccumulator ecotypes of Sedum alfredii.

This study aims to determine the spatial characteristics and real-time kinetics of cadmium transport in hyperaccumulator (HE) and non hyperaccumulator (NHE) ecotypes of Sedum alfredii using a non-invasive Cd-selective microelectrode. Compared with the NHE S. alfredii, the HE S. alfredii showed a higher Cd influx in the root apical region and root hair cells, as well as a significantly higher Cd efflux in the leaf petiole after root pre-treatment with cadmium chloride (CdCl(2)). Thus, HE S. alfredii has a higher capability for the translocation of absorbed Cd to the shoot. Moreover, the mesophyll tissues, isolated mesophyll protoplasts, and intact vacuoles from HE S. alfredii exhibited an instantaneous influx of Cd in response to CdCl(2) treatment with mean rates that are markedly higher than those from NHE S. alfredii. Therefore, the hyper-accumulating trait of HE S. alfredii is characterized by the rapid Cd uptake in specific root regions, including the apical region and root hair cells, as well as by the rapid root-to-shoot translocation and the highly efficient Cd-permeable transport system in the plasma membrane and mesophyll cell tonoplast. We suggest that the non-invasive Cd-selective microelectrode is an excellent method with a high degree of spatial resolution for the study of Cd transport at the tissue, cellular, and sub-cellular levels in plants.

Using coalescent simulations to test the impact of quaternary climate cycles on divergence in an alpine plant-insect association.

The Quaternary climate cycles forced species to repeatedly migrate across a continually changing landscape. How these shifts in distribution impacted the evolution of unrelated but ecologically associated taxa has remained elusive due to the stochastic nature of the evolutionary process and variation in species-specific biological characteristics and environmental constraints. To account for the uncertainty in genealogical estimates, we adopted a coalescent approach for testing hypotheses of population divergence in coevolving taxa. We compared genealogies of a specialized herbivorous insect, Parnassius smintheus (Papilionidae), and its host plant, Sedum lanceolatum (Crassulaceae), from the alpine tundra of the Rocky Mountains to null distributions from coalescent simulations to test whether tightly associated taxa shared a common response to the paleoclimatic cycles. Explicit phylogeographic models were generated from geologic and biogeographic data and evaluated over a wide range of divergence times given calibrated mutation rates for both species. Our analyses suggest that the insect and its host plant responded similarly but independently to the climate cycles. By promoting habitat expansion and mixing among alpine populations, glacial periods repeatedly reset the distributions of genetic variation in each species and inhibited continual codivergence among pairs of interacting species.

Pb uptake, accumulation, subcellular distribution in a Pb-accumulating ecotype of Sedum alfredii (Hance).

Lead concentrations in roots, stems and leaves of accumulating and non accumulating ecotypes of Sedum alfredii (Hance) were studied through a hydroponic experiment with different Pb concentrations supplied as Pb(NO(3))(2). Lead concentrations in leaves and stems of the accumulating ecotype were 4 - 9 times and 3 - 5 times those of the non-accumulating ecotype, and Pb accumulated amounts in stems and leaves of the accumulating ecotype were 4 - 9 times and 8 - 11 times higher than those of the non-accumulating ecotype, respectively. The results indicated that the accumulating ecotype had better ability to transport Pb from roots to shoots. The subcellular distributions of Pb in the root, stem and leaf tissues were studied using sucrose differential centrifugation. Approximately 50% of Pb contents was found to be associated with the cell wall fraction in stems of the accumulating ecotype and the percentage increased to 80% both in roots and leaves, no matter when plants were grown with different levels of Pb. The results indicated that the distribution of Pb on cell walls of the accumulating ecotype could mainly account for the high tolerance to Pb.