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Aspergillus flavus and the produced aflatoxins cause great hazards to food security and human health across all countries. The control of A. flavus and aflatoxins in grains during storage is of great significance to humans. In the current study, bacteria strain YM6 isolated from sea sediment was demonstrated effective in controlling A. flavus by the production of anti-fungal volatiles. According to morphological characteristics and phylogenetic analysis, strain YM6 was identified as Pseudomonas stutzeri. YM6 can produce abundant volatile compounds which could inhibit mycelial growth and conidial germination of A. flavus. Moreover, it greatly prevented fungal infection and aflatoxin production on maize and peanuts during storage. The inhibition rate was 100%. Scanning electron microscopy further supported that the volatiles could destroy the cell structure of A. flavus and prevent conidia germination on the grain surface. Gas chromatography/mass spectrometry revealed that dimethyl trisulfide (DMTS) with a relative abundance of 13% is the most abundant fraction in the volatiles from strain YM6. The minimal inhibitory concentration of DMTS to A. flavus conidia is 200 µL/L (compound volume/airspace volume). Thus, we concluded that Pseudomonas stutzeri YM6 and the produced DMTS showed great inhibition to A. flavus, which could be considered as effective biocontrol agents in further application.

Objective: To study the cytogenetic profiles of follicular lymphoma (FL) in Chinese patients., Methods: Conventional karyotype in 57 FL patients from Shanghai area was analyzed. Fluorescence in-situ hybridization (FISH) for t(14;18) and Bcl-6 and IgH gene rearrangement was performed in these cases., Results: The most frequent breakpoints (frequency > or = 10% ) of the 57 FL cases were at band 14q32 (68.4%), 18q21 (38.6%), 3q27 (21.1%), 1q10 (15.8%) and 1q21 (12.3%). Nineteen (33.3%) of the 57 cases had t(14;18). The breakpoint of 18q21 and t(14;18) were more frequent in FL grade 1-2 and less frequent in FL grade 3 (57.6% vs. 12.5%; 54.5% vs. 4.2%, P < 0.05), whereas the 3q27/Bcl-6 rearrangement was more frequent in FL grade 3 and less frequent in FL grade 1-2 (37.5% vs. 9.1% , P < 0.05). The cohort of FL was more frequent in gains of chromosomes X, 1q, 5, 6p, 7 and 12q and losses of chromosomes 1p, 6p and 14q32. Gain of 18q was more frequent in FL grade 1-2 than in FL grade 3 (P < 0.05). Loss of 14q32 was more frequent in t(14;18) negative FL than in t(14;18) positive FL (P < 0.05)., Conclusions: Compared with the data of Western patients reported in the literature, Chinese FL cases had distinct cytogenetic profiles from Western FL cases that the t(14;18) is less frequent and the gain of 1q is more frequent in Chinese FL cases, which are more significant in high grade FL.

Objective: To study the clinicopathologic features of urothelial hyperplastic lesion with an endophytic growth pattern and the role of immunohistochemistry and multitargeted fluorescence in situ hybridization (FISH) in the differential diagnosis., Methods: Forty-one cases of urothelial lesions exhibiting endophytic growth patterns were reviewed and reclassified as inverted papilloma, urothelial carcinoma with an endophytic growth pattern, and florid von Brunn nest. The gains of chromosomes 3, 7, and 17 and loss of 9p21 was detected by FISH, and performed immunohistochemical staining for CK20, p53, and Ki-67. Follow-up data of 12 cases were obtained., Results: (1) Twelve inverted papillomas sized 1.2 cm in average, consisted of anastomosing cords and nests with uniform width distribution involving the lamina propria, the central portion contained streaming cells with squamous metaplasia, and the periphery showed palisading. No or rare atypia and mitosis were found. Focal exophytic papillary component lined by less than 6 layers of normal urothelium were observed in 4 cases. (2) Twenty-four urothelial carcinomas with an endophytic growth pattern sized 2.1 cm in average, demonstrated the similar architecture with inverted papilloma, but exhibited thick columns and variable thickness of the cords, irregular size and shape of large nests with transition into solids. Mild to moderate cytologic atypia was shown, and mitotic figures ranged 1 to 8 per 10 HPFs. Exophytic papillary component was not observed in 3 cases, but the superficial urothelium showed dysplasia, while coexisted exophytic component in other cases was associated with low malignant potential or low grade tumor. (3) Five florid von Brunn nests sized 0.9 cm in average, had normal or hyperplastic urothelium, variable nests with cysts compacted in lamina propria, no cytologic atypia and mitosis. Twenty-one of 24 (79.1%) urothelial carcinomas with an endophytic growth pattern displayed abnormally positive results by multitargeted FISH, whereas all inverted papillomas and florid von Brunn nests were negative. Immunohistochemically, CK20 was weakly positive in 2 cases of urothelial carcinoma with an endophytic growth pattern, and negative in all inverted papillomas and florid von Brunn nests. p53 weakly stained 5% to 50% nuclei of the tumor cells in 16 cases of urothelial carcinomas with an endophytic growth pattern and 1 inverted papilloma. 1%-5% tumor cells expressed Ki-67 in urothelial carcinoma with an endophytic growth pattern, and less than 1% in inverted papilloma and florid von Brunn nests. Follow-up study revealed that 2 cases of urothelial carcinoma with an endophytic growth pattern had developed invasive carcinoma, underwent cystectomy, and metastasized remotely. No recurrence occurred in cases of inverted papilloma., Conclusions: Benign and malignant urothelial lesions with an endophytic growth pattern present histologic overlapping. Urothelial carcinoma with an endophytic growth pattern displays unique characteristics in morphology and immunohistochemistry. Multitargeted FISH analysis is helpful in the differential diagnosis.

Objective: To investigate the image features and the diagnostic value of spiral CT for cystic renal cell carcinoma., Methods: The clinical data and CT manifestations of 17 operated and pathologically proven cystic renal cell carcinoma were retrospectively analyzed. There were 12 males and 5 females with an average age of 47.3 years (33 - 82 years). Plain and contrast CT scan (Siemens somatom) single layer sensation 16 layer spiral CT had been performed before operation. The image of artery phase (30 - 40 s), venous (60 - 70 s) and excretory (120 - 180 s) were respectively obtained after contrast administration. Various image reconstructions were done using Siemens Wizard workstation based on the raw images., Results: It was found that 5 cystic renal cell cancers located in the right kidney and 12 in the left kidney. The long dimension of the tumor arranged from 21 - 100 mm with an average of 57 mm. The tumor looked like a round or round-like shape with density similar to fluid on plain CT scan. Some cystic renal carcinomas had a thick wall. Some had single or multiple cystic spaces filled with fluid of different densities. Some had infiltrated out of kidney surface or into renal sinus. Some showed enhanced nodules on the wall., Conclusion: Cystic renal cell carcinoma has its own specific morphologic features in spiral CT scan. Spiral CT may be very helpful in the diagnosis of cystic renal cell carcinoma before operation.