Unified Strategy Enables the Collective Syntheses of Structurally Diverse Indole Alkaloids.

Natural products and their analogues are significant sources of therapeutic lead compounds. However, synthetic strategies for generating large collections of these molecules remain a significant challenge. The most difficult step in their synthesis is the design of a common intermediate that can be easily transformed into natural products belonging to different families. This study demonstrates the evolution of synthetic tactics designed to assemble the functionalized piperidines present in indole alkaloids from a common intermediate. More importantly, we also report a previously unknown Ir- and Er-catalyzed dehydrogenative spirocyclization reaction that enables direct access to spirocyclic oxindole alkaloids. As a practical application, the asymmetric total syntheses of 29 natural alkaloids belonging to different families were accomplished by following a uniform synthetic route. The proposed methodology extends the capability of the iridium-catalyzed dehydrogenative coupling reaction to the realm of indole-alkaloid synthesis and provides new opportunities for the efficient preparation of natural product-like molecules.

Individual variation in metabolic rate, locomotion capacity and hypoxia tolerance and their relationships in juveniles of three freshwater fish species.

Individual variations in metabolic rate, locomotion capacity and hypoxia tolerance and their relationships were investigated in three cyprinid species [crucian carp (Carassius auratus), common carp (Cyprinus carpio) and qingbo (Spinibarbus sinensis), in 60 individuals of each species]. Either the active metabolic rate (AMR) and critical swimming speed (Ucrit) (30 individuals) or critical oxygen tension (Pcrit) and loss of equilibrium (LOE) (30 individuals) were measured in each species after measuring the resting metabolic rate (RMR). Both the AMR and Ucrit were found to be significantly and positively correlated with the RMR in all three cyprinid species, indicating that high-RMR individuals have high aerobic capacity and thus good swimming performance. Pcrit was positively correlated with the RMR in all three species, whereas the LOE was highly positively correlated, weakly positively correlated and not correlated with the RMR in qingbo, common carp and crucian carp, respectively, possibly due to specialized morphological and biochemical adaptations involved in hypoxia tolerance in crucian and common carp. Crucian carp showed relatively poor swimming performance, i.e., a low Ucrit (relatively high variation), strong hypoxia tolerance, and low LOE (relatively low variation); qingbo showed relatively good swimming performance (relatively low variation) and weak hypoxia tolerance (relatively high variation); and common carp showed moderate swimming performance and relatively strong hypoxia tolerance (moderate variation). These interspecific differences may be due to the different lifestyles of these cyprinid fishes based on their associated fast-slow-flow regime and are outcomes of long-term selection.

[Safety and efficacy of subcutaneous administration of bortezomib in the treatment of multiple myeloma].

OBJECTIVE: To analyze the efficacy and safety of subcutaneous administration of bortezomib in the treatment of multiple myeloma (MM) patients. METHODS: A total of 26 MM patients were enrolled in this study and treated with BDT (bortezomib-dexamethasone-thalidomide). In the 26 MM patients, 12 patients received subcutaneous administration of Bortezomib while 14 patients received conventional intravenous administration. The outcomes and adverse effects of two groups were retrospectively evaluated and compared. RESULTS: Overall response (OR) rates in the two groups were 75.00% and 71.43% respectively, in which complete remission (CR) plus very good complete remission (VGPR) rates were 50.00% and 47.14%, while CR rates were 16.67% and 28.57%. There were no statistically significant difference (P > 0.05). Time to achieve effectiveness in two groups was similar (P > 0.05). More than half patients in both groups achieved partial remission after the first treatment course and CR after the fourth course. Compared to the intravenous group, peripheral neuropathy rates remained significantly lower in subcutaneous group (16.67% vs. 64.29%, P = 0.021). The intravenous group had 7.14% grade 3 or worse, peripheral neuropathy but none found in the subcutaneous group. Rash occurred only in subcutaneous group (66.67%), but it was local, mild and transitional. No significant differences of other adverse events between the two groups were observed. CONCLUSION: Subcutaneous administration of bortezomib offers similar efficacy to standard intravenous administration in the treatment of multiple myelom, with an improved safety for lower rate of peripheral neuropathy.

Efficacy of beta-adrenergic blocker plus 5-isosorbide mononitrate and endoscopic band ligation for prophylaxis of esophageal variceal rebleeding: a meta-analysis.

AIM: To systematically assess the efficacy and safety of beta-adrenergic blocker plus 5-isosorbide mononitrate (BB + ISMN) and endoscopic band ligation (EBL) on prophylaxis of esophageal variceal rebleeding. METHODS: Randomized controlled trials (RCTs) comparing the efficacy and safety of BB + ISMN and EBL on prophylaxis of esophageal variceal rebleeding were gathered from Medline, Embase, Cochrane Controlled Trial Registry and China Biological Medicine database between January 1980 and August 2007. Data from five trials were extracted and pooled. The analyses of the available data using the Revman 4.2 software were based on the intention-to-treat principle. RESULTS: Four RCTs met the inclusion criteria. In comparison with BB + ISMN with EBL in prophylaxis of esophageal variceal rebleeding, there was no significant difference in the rate of rebleeding [relative risk (RR), 0.79; 95% CI: 0.62-1.00; P = 0.05], bleeding-related mortality (RR, 0.76; 95% CI: 0.31-1.42; P = 0.40), overall mortality (RR, 0.81; 95% CI: 0.61-1.08; P = 0.15) and complications (RR, 1.26; 95% CI: 0.93-1.70; P = 0.13). CONCLUSION: In the prevention of esophageal variceal rebleeding, BB + ISMN are as effective as EBL. There are few complications with the two treatment modalities. Both BB + ISMN and EBL would be considered as the first-line therapy in the prevention of esophageal variceal rebleeding.

High-level expression of basic fibroblast growth factor in transgenic soybean seeds and characterization of its biological activity.

The glycinin G1 gene encodes a soybean seed storage protein accumulating at a high level. We have used the G1 promoter to confer seed-specific expression of human basic fibroblast growth factor (bFGF) in transgenic soybeans. The coding region of 18 kDa bFGF was fused to the promoter or promoter-signal peptide sequence of G1 gene, and transferred into soybean. Analysis of transgenic plants demonstrated that bFGF transcript or protein was confined to the seeds. The highest level of bFGF accumulation in the seeds reached up to 2.3% of total soluble protein. The soybean-derived bFGF was biologically active as confirmed by its mitogenic activity on Balb/c 3T3 cells, and exhibited other properties identical to native bFGF. We also observed a seed-specific expression of beta-glucuronidase driven by the G1 promoter. These results indicated that the G1 promoter contains essential cis-elements for seed-specific expression, and thus can be used for expression of pharmaceutical proteins in soybean seeds.