Competition between bacteria and phosphate for adsorption sites on gibbsite: An in-situ ATR-FTIR spectroscopic and macroscopic study.

Sorption and desorption of phosphate (P) on Fe and Al (hydr)oxides may be affected by bacteria in soils because their ubiquitous and strong interactions. The role of Bacillus subtilis and Pseudomonas fluorescens in adsorption of P on gibbsite (γ-AlOOH) was systematically investigated under a wide range of conditions by combining in-situ attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy with batch macroscopic experiments. In-situ ATR-FTIR observations of the ternary systems (bacteria, P, and gibbsite) showed simultaneous desorption of P from, and adhesion of the bacteria to, gibbsite, indicating a competition between the two for surface sites. Batch desorption experiments showed that bacteria could mobilize the P from gibbsite into solution, and macroscopic adsorption data showed that the amount of P adsorbed on the bacteria-gibbsite complex was less than that on gibbsite alone over durations from 0h to 26h, concentrations of P from 0.1mM to 2.0mM, pH from 5 to 8, and ionic strength from 0M to 0.5M, suggesting that bacteria inhibit the adsorption of P on gibbsite. The degree of inhibition increased with the number of bacteria in the system and was significantly but non-linearly correlated with the decline in the positive charge on gibbsite induced by the bacteria. Therefore, competition for suitable sites on the surface of gibbsite between P and the bacteria and reduction in the positive charge on the surface of gibbsite induced by bacteria are proposed as two important mechanisms that inhibit P adsorption. These findings highlight the role of bacteria in regulating the availability of P to plants and its mobility in natural environments.

Primary lymphoepithelioma-like carcinoma of salivary glands: a clinicopathological study of 21 cases.

Lymphoepithelioma-like carcinoma (LELC) of salivary glands is a rare kind tumor. In this study, the authors evaluated 21 patients with LELC of salivary glands who had long-term follow-up. Clinical characteristics, Epstein-Barr virus (EBV) infection, immunohistochemical features, oncoprotein expression, treatments, and outcomes were analyzed. All patients were Chinese. Their ages ranged from 20 to 73 years. All tumors showed the typical syncytial growth pattern of undifferentiated epithelial cells with a significant lymphocyte reaction. All of patients were found by in situ hybridization to have the EBV genome. All tumors showed positive immunostaining of AE1/AE3, CK5/6 and p63. Nearly all cases had bcl-2 oncoprotein expression, but the detection rate of p53, and c-erb B-2 expression was extremely low. LELC of salivary glands is a distinct entity of salivary cancer. LELC of salivary glands can receive multimodality treatment and has a better prognosis similar to that of nasopharyngeal carcinoma.

Isolation, identification, and complete genome sequence of a bovine adenovirus type 3 from cattle in China.

BACKGROUND: Bovine adenovirus type 3 (BAV-3) belongs to the Mastadenovirus genus of the family Adenoviridae and is involved in respiratory and enteric infections of calves. The isolation of BAV-3 has not been reported prior to this study in China. In 2009, there were many cases in cattle showing similar clinical signs to BAV-3 infection and a virus strain, showing cytopathic effect in Madin-Darby bovine kidney cells, was isolated from a bovine nasal swab collected from feedlot cattle in Heilongjiang Province, China. The isolate was confirmed as a bovine adenovirus type 3 by PCR and immunofluorescence assay, and named as HLJ0955. So far only the complete genome sequence of prototype of BAV-3 WBR-1 strain has been reported. In order to further characterize the Chinese isolate HLJ0955, the complete genome sequence of HLJ0955 was determined. RESULTS: The size of the genome of the Chinese isolate HLJ0955 is 34,132 nucleotides in length with a G+C content of 53.6%. The coding sequences for gene regions of HLJ0955 isolate were similar to the prototype of BAV-3 WBR-1 strain, with 80.0-98.6% nucleotide and 87.5-98.8% amino acid identities. The genome of HLJ0955 strain contains 16 regions and four deletions in inverted terminal repeats, E1B region and E4 region, respectively. The complete genome and DNA binding protein gene based phylogenetic analysis with other adenoviruses were performed and the results showed that HLJ0955 isolate belonged to BAV-3 and clustered within the Mastadenovirus genus of the family Adenoviridae. CONCLUSIONS: This is the first study to report the isolation and molecular characterization of BAV-3 from cattle in China. The phylogenetic analysis performed in this study supported the use of the DNA binding protein gene of adenovirus as an appropriate subgenomic target for the classification of different genuses of the family Adenoviridae on the molecular basis. Meanwhile, a large-scale pathogen and serological epidemiological investigations for BVA-3 infection might be carried out in cattle in China. This report will be a good beginning for further studies on BAV-3 in China.

[Evaluation of soil quality under different land use types in Naban River watershed, Yunnan Province of Southwest China].

Eighty-six topsoil (0-20 cm) samples were collected from 8 land use types (natural forest land, maize field, tea garden, paddy field, rubber plantation, flax field, banana plantation, and sugarcane field) in the Naban River Watershed National Nature Reserve and its surrounding areas, and the soil physical and chemical properties were analyzed, aimed to study the effects of land use type on the soil quality by the method of soil quality index (SQI). Comparing with natural forest land, all the cultivated lands had somewhat decreased soil organic matter content and higher soil bulk density, and the soil bulk density was significantly higher in tea garden, paddy field, rubber plantation, and banana plantation. In cultivated lands, fertilization and reclamation made the soil available potassium and phosphorus contents maintained at a higher level, probably due to the input of mineral potassium and phosphorus and the decomposition of soil organic matter. The SQI of the 8 land use types was in the order of flax field (0.595) > natural forest land (0.532) > maize field (0.516) > banana plantation (0.485) tea garden (0.480) sugarcane field (0.463) > paddy field (0.416) > rubber plantation (0.362). The soils in higher altitude production demonstration areas (1614 +/-115 m) had significant higher SQI, compared to the soils in lower altitude buffer areas (908 +/- 98 m) and junction areas (926 +/- 131 m). Among the 8 land use types, the rubber plantation in lower altitude areas had the lowest SQI, due to the lower soil organic matter and available potassium and phosphorus contents and the highest soil bulk density. Application of organic manure or intercropping with leguminous plants could be an available practice to improve the soil quality of the rubber plantation.

[Kinetics and thermodynamics of Cd (II) adsorption onto particle-sized fractions of yellow-brown soil].

A batch method was used to investigate the kinetics and thermodynamics of cadmium adsorption onto different particle-sized fractions (2 000 - 200 microm, 200 - 20 microm, 20 - 2 microm and 2 - 0 microm, which were named coarse sand, fine sand, silt and clay respectively according to international system) derived from yellow brown soil by using a novel technology combined with wet sieving, sedimentation-siphoning and centrifugation method. The results showed that the reaction of adsorption can be divided into two types: a fast reaction in the first 15 min and a slow reaction in the later reaction course. The amounts of Cd2+ adsorbed by the fast reaction exceed 95% of the adsorption capacity. As the temperature increased from 25 degrees C to 45 degrees C, the adsorption capacities of the four fractions increase by 4.86%-25.3%. First-order rate equation and pseudo second-order rate equations were applied to express adsorption kinetics. Adsorption processes for Cd2+ onto the four fractions were found to follow pseudo-second order type adsorption kinetics. The pseudo second-order rate constants exhibited that adsorption speed to reach equilibrium decreased with the increase of particle size. Intra-particle diffusion might be the major rate-limiting step. Thermodynamic parameters including deltaH0, deltaS0 and deltaG0 were also calculated from graphical interpretation of the experimental data. Positive deltaH0 values indicated the adsorption processes to be endothermic. Negative deltaG0 values implied that adsorption reaction was a spontaneous process.