Hannaella dianchiensis sp. nov., a basidiomycetous yeast species isolated from lake water.

Three strains (YIM-HL1107T, YIM-HL1045, YIM-HL1112) representing a novel yeast species were isolated from surface water samples collected from the Caohai region of Dianchi Lake in Yunnan, south-western China. On the basis of morphological, physiological and biochemical characteristics and sequence analysis of the D1/D2 region of the LSU rRNA gene and the internal transcribed spacer (ITS) region, they were assigned to a novel species of the genus Hannaella. The closest relative to the novel species was Hannaella pagnoccae, but it showed 6.3 % nucleotide differences (34 nt substitutions out of 541 nt) in the D1/D2 region of the LSU rRNA gene and 9.3-9.6 % nucleotide differences (40-41 substitutions and 7-8 gaps out of 430 nt) in the ITS region. The name Hannaella dianchiensis sp. nov. is proposed. The type strain is YIM-HL1107T (=CBS 14191T=CCTCC AY 2015009T), and the MycoBank number is MB 816297.

[Effects of land use type on spatiotemporal distribution of soil nutrients in Dianchi watershed, Yunnan Province of Southwest China].

Surface soil samples were monthly collected from six land use types (abandoned greenhouse field, forest land, sloped farmland, table land, flat vegetable land and greenhouse field) in Dianchi watershed of Yunnan to determine the soil pH and the contents of soil organic matter (OM), total nitrogen (TN), and total phosphorus (TP), aimed to understand the effects of different land use types on the spatiotemporal distribution of the soil nutrients. The soil pH, SOM, TN and TP, contents, and soil C/N differed significantly with soil land use types. The soil pH was in the order of abandoned greenhouse field > flat vegetable land > greenhouse field > table land > sloped farmland > forest land; the OM content was in the sequence of abandoned greenhouse field > flat vegetable land > greenhouse field > sloped farmland > forest land > table land; the TN content was in the order of greenhouse field > flat vegetable land > abandoned greenhouse field > sloped farmland > table land > forest land; the TP content was in the order of flat vegetable field > greenhouse field > abandoned greenhouse field > sloped farmland > table land > forest land; and the C/N ratio was in the sequence of forest land > sloped farmland > flat vegetable plot > table land > abandoned greenhouse field > greenhouse field. The OM, TN and TP contents were affected by fertilization, irrigation, field cultivation and season. All the test parameters had the highest values in rainy season, which could be related to the local top-dressing habits. There were significant positive correlations among the TN, TP and OM under all the land use types. In greenhouse field and abandoned greenhouse field, due to the severe human disturbances, the soil pH and OM, TN and TP contents were obviously higher than those in forestland and table land.

[Effects of emodin on the intracellular calcium concentration ([Ca2+]i) and L-type calcium current of the single ventricular mytocytes from guinea pig].

AIM: To study the effects of emodin on intracellular calcium concentration ([Ca2+]i) and L-type calcium current of the single ventricular myocytes from guinea pig. METHODS: Enzymatic dissociation was used to isolate single ventricular myocytes from adult guinea pig. They were loaded with Ca2(+)-sensitive fluorecent indicator Fluo-3/AM. [Ca2+]i represented by fluorescent intensity (FI) was measured by laser scanning confocal microscope. Whole cell patch clamp technique was used to record ICa-L. RESULTS: At resting status, [Ca2+]i was not affected by emodin (1-100 mumol.L-1). Emodin at the concentration of 1 mumol.L-1 was shown to increase the [Ca2+]i induced by 60 mmol.L-1 KCl. The peak value of fluorescent intensity was increased from 1,877 +/- 551 to 2,905 +/- 739 (n = 8, P < 0.05). Emodin at the concentration of 10 mumol.L-1 had no effect on the increase of [Ca2+]i induced by 60 mmol.L-1 KCl. However, the increase of [Ca2+]i induced by KCl was reduced to 1,214 +/- 335 (n = 8, P < 0.05) by 100 mumol.L-1 emodin. The density of ICa-L was increased from (-6.2 +/- 1.3) pA/pF to (-8.3 +/- 0.3) pA/pF (n = 6, P < 0.05) by 1 mumol.L-1 emodin at the test pulse of 0 mV. The current was not altered by 10 mumol.L-1 emodin. But it was inhibited from (-6.6 +/- 1.0) pA/pF to (-3.80 +/- 0.16) pA/pF (n = 6, P < 0.05) by 100 mumol.L-1 emodin at the test pulse of +10 mV. CONCLUSION: Emodin has two-way regulation on [Ca2+]i and ICa-L of cardiomyocytes in guinea pig.