[Potential to Ensure Safe Production from Rice Fields Polluted with Heavy Cadmium by Combining a Rice Variety with Low Cadmium Accumulation, Humic Acid, and Sepiolite].

The study investigated the potential of ensuring safe production of rice from paddy fields affected by heavy cadmium contamination. A paddy soil polluted with heavy cadmium (total Cd content of 2.52 mg·kg-1) surrounding a lead-zinc mining area in Guiyang County of Chenzhou City, Hunan province was selected for analysis. We investigated production using a low cadmium accumulation rice variety (Oryza sativa L. Jia-33) and passivation additives for heavy metal activity (including humic acid and sepiolite). Results showed that:Oryza sativa L. Jia-33 showed good low cadmium accumulation characteristics in rice fields with heavy cadmium pollution. When humic acid and sepiolite were applied (alone or combined), the accumulation of Cd in different organs of the rice declined, and the transport coefficient of Cd for stem to root and polished rice to stem also declined. The rate of decline increased with increased application dosage. The cadmium content in polished rice was lower than the limit established in the National Food Safety Standard (GB 2715-2012), when applying 5.250 t·hm-2 humic acid, 6.750 t·hm-2 sepiolite, or a combination of 1.125 t·hm-2 humic acid and 3.37 5 t·hm-2 sepiolite; Cd content in polished rice was (0.171±0.01), (0.184±0.01), and (0.181±0.01) mg·kg-1, respectively. Single or combined application of humic acid and sepiolite promoted the transformation of soil Cd to residual and Fe Mn oxide bound forms, significantly reducing the content of available Cd and the bioavailability of Cd in soil, and further reducing Cd content in all rice organs. The reduction was more effective with single application of sepiolite or combined application of humic acid and sepiolite. The effects of combined application of humic acid and sepiolite were also more beneficial for soil nutrients, while soil available phosphorus, available potassium, phosphorus, and organic matter content increased with increased application of amendments. Soil nitrogen content did not change. In conclusion, results indicate that joint application of humic acid, sepiolite, and a low Cd accumulation rice variety are best for safe production on heavy cadmium-contaminated soil.

[Effects of Carthamus tinctorius injection on bcl-2, caspase-3 expression related to neurons apoptosis after local cerebral ischemia].

OBJECTIVE: To investigate the effects of Carthamus tinctorius on bcl-2, caspase-3 expression of apoptosis of neurons. METHOD: SD rats were randomly divided into ischemia control group, large-dose group, middle-dose group and low-dose group. The middle cerebral artery of rats was occluded for 2h by inserting an introluminal molofilament, and reperfusion was then instituted for 4h or 22h. The brains were stained with 2, 3, 5-triphenylte trazolinm chloride for assessment of volume of infarction, and then embedded onto slides with paraffin for morphological assessment and immunohistochemistry was carried out to investigate the changes in bcl-2 and caspase-3. RESULT: All treated groups at different times decreased the volume of infarction (P < 0.05), while large-dose group showed more distinct decrease than other groups (P < 0.05). All treated groups at different times increased bcl-2 and decreased caspase-3 expression as well, while large-dose group showed more distinct effect (P < 0.05). CONCLUSION: C. tinctorius injection can reduce the volume of cerebral infarction, and increased bcl-2 and decreased caspase-3 expression.

Immunocytochemical identification and localization of APUD cells in the gut of seven stomachless teleost fishes.

AIM:To study the cell types, localization, distribution density and morphology of APUD cells in the intestinal mucosa of stomachless teleost fishes.METHOD:By using the peroxidase antiperoxidase complex (PAP) immunocytochemical staining technique the identification, localization and morphology of immunoreactive (IR) endocrine cells seattered in the intestinal mucosa of grass carp (Cyenopharyngodon idellus), black carp ( Mylopharyngodon piceus ) and common carp (Cyprinus carpio) were investigated with 20 kinds of antisera prepared against mammalian peptide hormones of APUD cells, and likewise by using avidin-biotin-peroxidase complex (ABC) method those of silver carp (Hypophthalmichthys molitrix), bighead (Aristichthys nobilis), silver crucian carp (Carassius gibelio) and bluntnose black bream (Megalobrama amblyocephala ) were also studied with 5 different antisera. The replacement of the first antiserum by phosphate buffered saline (PBS) was employed as a control. IR endocrine cells were counted with a square-mesh ocular micrometer from 10 fields selected randomly in every section of each part of the intestine specimen. The average number of IR endocrine cells per mm(2) was counted to quantify their distribution density.RESULT:Gastrin (GAS), Gastric inhibitory peptide (GIP), glucagon (GLU), glucagons like immunorea-ctants (GLI), bovine pancreatic polypeptide (BPP), leucine-enkephalin (ENK) and substance P (SP)-IR endocrine cells were found in the gut of grass carp, black carp and common carp, and somatostatin (SOM) IR endocrine cells were only seen in common carp. GAS, GIP and GLU-IR endocrine cells were found in the intestinal mucosa of silver carp, bighead, silver crucian carp and bluntnose black bream. Most of IR endocrine cells had the higher distribution density in the foregut and midgut, and were longer in shape. They had a long apical cytoplasmic process extended to the gut lumen and a basal process extended to adjacent cells or basement membrane and touched with it. Sometimes, the basal cytoplasmic process formed an enlarged synapse-like structure in the contiguous part with basement membrane. This phenomenon provided new morpho-logical evidence for neuroendocrine and paracrine secretory function of these enteroendocrine cells.CONCLUTION:At least 8 kinds of IR endocrine cells were found in the gut of stomachless teleost species for the first time in China. These IR endocrine cells scattering in the gut mucosa belong to the APUD system. Among them, the hormones secreted by SP-, ENK-, SOM- and GLU-IR endocrine cells belong to the peptides of dual distribution in the brain and gut. This provided new evidence for the concept of brain-gut peptide. According to the cell types, distribution density, morphological characteristics and variety in shape of APUD cells in the gut of stomachless teleost fishes, it is deemed that the digestive tract of fishes is also an endocrine organ of great importance and complexity.