Two new 19-norbufadienolides with cardiotonic activity isolated from the venom of Bufo bufo gargarizans.

Two new 19-norbufadienolides (1 and 2) and one new 14,15-epoxy bufadienolide (3) alongside 16 known bufadienolides (4-19) were isolated from Bufonis Venenum that originated from the skin and parotid venom glands of an Asiatic toad (Bufo bufo gargarizans Cantor). The structures of these bufadienolides were elucidated based on the interpretation of their HRESIMS and NMR data. Compound 1, which had a unique peroxide, was established through extensive single-crystal X-ray diffraction. The two 19-norbufadienolides exhibited more potent cardiotonic activity in the isolated toad heart model and lower cytotoxicity against U87, U251, and LN-18 cell lines than other bufadienolides, such as bufalin and bufotalin. The results suggested that 19-norbufadienolides might be more suitable for developing cardiotonic agents with low cytotoxicity.

[Strategies of interventing complications in hemodialysis with classical prescriptions from clinical cases].

There are 400 thousand patients with long-term hemodialysis in China nowadays. Hemodialysis, as the most common alternative to renal replacement therapy, prolongs the life span of patients with end stage renal failure. However, there are still many complications of hemodialysis treatment. These complications reduce the quality of life of patients and may even endanger their life, and sometimes they are difficult to deal with. Classical prescriptions, commonly referred to as classical effective prescriptions in modern medicine, mainly indicating the formulas recorded in Treatise on Febrile Diseases and Synopsis of Golden Chamber, were relative to contemporary prescriptions emerging after Song and Yuan dynasties. Prescriptions corresponding to syndromes means one-to-one correspondence between syndromes and prescriptions, with many advantages and that is the key of clinical efficacy. Many complications of hemodialysis patients have typical clinical manifestations, which can match the syndromes corresponding to classical prescriptions, thus quickly relieving the symptoms of patients in clinical application. Six clinical cases of dialysis muscle spasm, disequilibrium syndrome, restless legs syndrome, uremic encephalopathy, post dialysis arrhythmia, and secondary hyperparathyroidism were used in this paper, to explore the intervention strategies for hemodialysis related complications.

Antinociceptive and anti-inflammatory activities of a standardizedextract of bis-iridoids from Pterocephalus hookeri.

ETHNOPHARMACOLOGICAL RELEVANCE: Pterocephalus hookeri (C.B. Clarke) Höeck, one of the most popular Tibetan herbs, has been widely applied in Tibetan medicine prescriptions. Chemical investigations have led to the isolation of many bis-iridoids. However, the pharmacological activities of bis-iridoid constituents of this plant have never been reported before. AIM OF THE STUDY: This study evaluated the anti-inflammatory and analgesic activities of afraction of bis-iridoid constituents of P. hookeri (BCPH) in order to provide experimental evidence for its traditional use, such as for cold, flu, and rheumatoid arthritis. MATERIALS AND METHODS: The analgesic effects of BCPH were investigated using the hot-plate test and acetic acid-induced writhing test. The anti-inflammatory activities were observed using the following models: carrageenin-induced edema of the hind paw of rats and xylene-induced ear edema in mice. The effects of dexamethasone administration were also studied. RESULTS: BCPH significantly increased the hot-platepain threshold and reduced acetic acid-induced writhing response in mice. Moreover, BCPH remarkably inhibited xylene-induced ear edema and reduced the carrageenin-induced rat paw edema perimeter. CONCLUSION: The results reveal that BCPH has central, peripheral analgesic activities as well as anti-inflammatory effects, supporting the traditional application of this herb in treating various diseases associated with inflammation and pain.

Identification and characterization of an extracellular alkaline phosphatase in the marine diatom Phaeodactylum tricornutum.

In phosphorus-deficient conditions, Phaeodactylum tricornutum releases an alkaline phosphatase (PtAPase) to the medium that is readily detectable by activity staining. Nucleic acid and amino acid sequence of this alkaline phosphatase (APase) was identified by performing proteomic analysis and database searches. Sequence alignment suggests that PtAPase belongs to the PhoA family, and it possesses key residues at the Escherichia coli PhoA active site. Quantitative PCR results indicate that the induction of APase mRNA transcription is very sensitive to phosphorus availability and population growth. The molecular mass of native PtAPase (148 kDa) determined by gel filtration chromatography indicates that PtAPase, like most PhoA, is homodimeric. Zn and Mg ions are essential cofactors for most PhoA enzymes; however, PtAPase activity did not require Zn ions. In fact, 5 mM Zn²âº, Mo²âº, Co²âº, Cd²âº, or Cu²âº inhibited its enzymatic activity, whereas 5 mM Mn²âº, Mg²âº, or Ca²âº enhanced its enzymatic activity. The responses of PtAPase to divalent metal ions were different from those of most PhoAs, but were similar to the PhoA in a marine bacterium, Cobetia marina. Phylogenetic analysis shows that homologs of PhoA are also present in other diatom species, and that they clustered in a unique branch away from other PhoA members. PtAPase may represent a novel class of PhoA that helps diatoms to survive in the ocean. Quantification of the PtAPase mRNA may help monitor the physiological condition of diatoms in natural environments and artificial bioreactors.