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Two homologous meroterpenoid gene clusters consisting of contiguous genes encoding polyketide synthase (PKS), prenyltransferase (PT), terpenoid cyclase (TC) and other tailoring enzymes were identified from two phylogenetically distinct fungi through computational analysis. Media optimization guided by reverse-transcription PCR (RT-PCR) enabled two strains to produce eight new and two known meroterpenoids (1-10). Using gene inactivation, heterologous expression, and biochemical analyses, we revealed a new polyketide-terpenoid assembly line that utilizes a pair of PKSs to synthesize 2,4-dihydroxy-6-alkylbenzoic acid, followed by oxidative decarboxylation, farnesyl transfer, and terpene cyclization to construct the meroterpenoid scaffold. In addition, two of the isolated meroterpenoids (3 and 17 d) showed immunosuppressive bioactivity. Our work reveals a new strategy for meroterpenoid natural products discovery, and reveals the biosynthetic pathway for compounds 1-10.

Five new aromatic polyketides, alternaphenols A-E (1-5), and two known compounds (6-7) were isolated from a liquid culture of Alternaria sp. (strain no. NF2198), a caterpillar associated fungus. Their structures were determined by extensive spectroscopic analysis and single crystal X-ray crystallography. Compounds 1-7 were evaluated for their cytotoxic activities against a human skin melanoma A-375 cell line. Only compounds 4 and 5 showed weak cytotoxic activities.

Nodupetide (1), a new cyclodepsipeptide unique in its incorporation of a 3-hydroxy-4-methylhexanoic acid (HMHA) derived motif, was discovered from Nodulisporium sp. IFB-A163, a fungus residing in the insect (Riptortus pedestris) gut. The nodupetide structure was elucidated by its MS/MS and 2D NMR spectra, and its absolute configuration by the X-ray crystallography and modified Marfey’s method. Nodupetide is insecticidal against rice brown planthopper (Nilaparvata lugens) with an LD50 value of 70 ng/larva, and inhibitory towards the drug-resistant human pathogenic bacterium Pseudomonas aeruginosa with its MIC value (5.0 μM) comparable to that (3.2 μM) of ciprofloxacin, a prescribed antibacterial agent co-assayed equally.

Chaetospirolactone (1), a novel spiro-lactone bearing a rare 1-oxaspiro [4.4] non-7-ene-2,6-dione skeleton, and orsellide F (2), together with six known compounds (3–8), were isolated from an endophytic fungus Chaetomium sp. NF00754. Their structures were determined by interpretation of spectroscopic data. The absolute configurations of 1 and 2 were established by analysis of single X-ray crystallographic data and CD spectra. Compounds 3, 4, and 6 showed moderate acetylcholinesterase inhibitory activity with IC50 values of 7.34, 5.19, and 7.67 μM, respectively.

To construct a platform for Schistosoma japonicum infection real-time monitoring and early warning in marshlands along the Yangtze River.The data of the status of Oncomelania hupensis snails, schistosomiasis endemic situation, marshland environment status, and other basic information were collected and analyzed comprehensively in marshlands along the Yangtze River in Jiangsu Province, and a schistosomiasis endemic situation electronic map was established. Through the GPS and 3G technology, the short messaging service (SMS) alerts were sent to the fishermen when they entered the areas of different schistosomiasis endemic levels in real-time.The SMS alerts reminded the fishermen to adopt the suitable interventions to reduce or avoid the schistosome infection. In addition, the data of moving track of mobile phones of fishermen, and the examination and treatment of schistosomiasis at each monitoring point were collected and analyzed comprehensively and then systematic analysis reports of schistosomiasis situation prediction, early warning, related evaluation, etc. were created in real-time.The platform for Schistosoma japonicum infection real-time monitoring and early warning in marshlands along the Yangtze River has a certain application value for schistosomiasis prevention and control work of Jiangsu Province and even whole country.

To understand the knowledge and practice on schistosomiasis control of boatmen along the Yangtze River, so as to provide the evidence for making up schistosomiasis control measures for them.In the anchor spots along the Yangtze River in Xinbei District, Changzhou City, a questionnaire survey was carried out for boatmen's knowledge and practice on schistosomiasis control. Among the boatmen of different genders, ages and education levels, the awareness rates of schistosomiasis control knowledge and the formation rates of correct behavior were compared.A total of 702 boatmen of 231 boats were surveyed. The total awareness rate of schistosomiasis control knowledge was 84.19%. Among the groups with different education levels, the awareness rates were significantly different (chi2 =14.42, P0.05). The total formation rate of correct behavior on schistosomiasis control was 43.16%. Between men and women groups, and among groups with different ages, the formation rates were significantly different (chi2 = 21.95, 15.00, P0.05 for all). Totally 94.81% of the boats discharged the excrement into water directly.The formation rate of correct behavior on schistosomiasis control of boatmen was low, thus the health promotion should be enhanced for them.

Crystalline films of La0.65Pb0.35MnO3 grown on Si (100) substrates by rf sputtering have been investigated by ferromagnetic resonance and MOKE. The dependence of the ferromagnetic resonance line parameters on the sample orientation and temperature is investigated. An expression for the angular dependence of the resonance field on the orientation of the sample is proposed, based on the assumption that close to the Curie temperature the Zeeman and demagnetizing terms are dominant. MOKE data support this hypothesis. The temperature dependence of the magnetization at saturation, in relative units, estimated from ferromagnetic resonance agrees with SQUID data.