Five fractions,Ⅰ(R_f0.06)、Ⅱ(R_f0.21)、Ⅲ(R_f0.45)、Ⅳ(R_f0.60)、Ⅴ(R_f0.75)have been obtained after HT-toxin from race 1 of Exserohilum turcicum 99-2 isolated by TLC. In all of these fractions,only fractions Ⅱ had specific toxicity to the corn leaves with Ht1 gene. Then fractions Ⅱ-1、Ⅱ-2、Ⅱ-3 were isolated from fractions Ⅱ by HPLC purification,and the bioassay result showed only fraction Ⅱ-3 was toxigentic to corn leaves with Ht1 gene but non-toxigentic to corn leaves without Ht1 gene. Fractions Ⅱ-1、Ⅱ-2 and Ⅱ-3 were scanned by UV-Vis spectrophotometer. It was shown that the fractions Ⅱ-1 and Ⅱ-2 had analogous spectrum,and especially the fraction Ⅱ-3 had a special peak at 300nm.

OBJECTIVE To investigate the pathogenic causes of lower respiratory tract infections(LRTIs) in the elderly in Guangzhou area.METHODS Pathogens obtained from 107 patients with LRTIs were performed by multiple diagnostic tools that including bacterial culture,PCR and specific immunological assays.RESULTS A bacterial cause was established in 42(68.5%) and an atypical pathogen cause in 25(31.6%) of the 107 patients.Mycoplasma pneumoniae and Haemophilus influenzae remained the most important pathogens for LRTIs.CONCLUSIONS In the prescription of antibiotics in the elderly with LRTIs,not only bacteria but also atypical pathogens should be taken into account.

Objective To investigate whether determination of CEA and CA19-9 levels in EUS-FNA pancreatic samples can be useful in detecting pancreatic adenocarcinoma and differentiating pancreatic adenocarcinoma from chronic pancreatitis.Methods Levels of CEA,CA19-9 were examined by chemiluminescence immunoassay analysis in EUS-FNA specimens obtained from 25 patients with chronic pancreatitis and 65 patients with pancreatic adenocarcinoma,and compared with those of their peripheral serum.Twelve patients with suspected pancreatic adenocarcinoma while with negative EUS-FNA pathological findings were followed up.Results First,the levels of CEA,CA19-9 in EUS-FNA specimens were higher than those in serum obtained from same patient with pancreatic adenoearcinoma(P＜0.01),but there was no difference in these variables of EUS-FNA specimens and serum obtained from patients with chronic pancreatitis.Second,in the EUS-FNA samples,the levels of CEA,CA19-9 in pancreatic adenocarcinoma were higher than those in chronic pancreatitis(P＜0.01).On the contrary,in serum samples,there was no significant difference in CEA level between pancreatic adenocarcinoma and chronic pancreatitis(P=0.079).CA19-9 level in serum of Dancreatic adenocarcinoma was higher than that of chronic pancreatitis(P＜0.01). Finally,during the follow-up,of all the 12 patients with suspected pancreatic adenocarcinoma,10 patients were diagnosed as having pancreatic adenocarcinoma and 2 patients as having chronic pancreatitis.Diagnostic accuracy of serum CEA and CA19-9were 30%and 70%respectively,while sensitivity of CEA and CA10-9 determined by EUS-FNA was both above 90%.Conclusion The method of measuring CEA and CA19-9 levels in samples obtained by EUS-FNAcan be useful in detection of pancreatic adenocarcinoma and differentiation of malignant pancreatic tissue from chronic pancreatitis.

Objective To examine the effect of metformin on serum thyrotropin (TSH) level in diabetic patients with subclinical hypothyroidism (SCH).Methods The long-term effects of metformin on thyroid axis hormones were assessed in 55 diabetic patients with primary SCH who were untreated with L-T4(study group),as well as in 31 diabetic patients with normal thyroid function (control group).According to using metformin or not,patients of study group were divided into the metformin group (group 1,n =28),and the non-metformin group(group 2,n =27).Serum TSH levels were compared between baseline and follow-up in patients receiving metformin treatment.Results After 30 weeks of metformin administration,a significant TSH decrease(t =2.91,P ＜ 0.05) was observed in group 1 [from(6.98 ± 1.92) to(2.44 ± 0.61) mIU/L].After stopping metformin therapy,the level of TSH at 52 weeks fol low-up was back to the baseline level [(6.99 ± 1.76) mIU/L,P ＞ 0.05].There was no significant difference in TSH level between baseline and after 30 weeks follow-up in group 2[(6.01 ± 1.63) mIU/L vs(6.21 ± 1.71) mIU/L,P ＞0.05].At the end of 30 weeks follow-up,no significant differences were found in body mass index and thyroid func tion in both metformin group and non-metformin group.In control group,metformin administration for 30 weeks had no effect on TSH level(P ＞ 0.05).Conclusion Metformin administration influences TSH without change of FT4 level in type 2 diabetic patients with primary SCH.

Melanin is formed by oxidative polymerization of phenolic compounds,basically different kinds of melanin come from different organisms.DOPA melanin and DHN melanin have same physical and chemical characters although they have different biosynthetic pathway.DHN melanin is common in plant fungi and plays an important role on infection.The melanin accumulates in the fungal cell walls and prevents organic and inorganic molecules penetrating out,that insures appressorium's pressure and infection ability.This paper has reviewed the kinds and characters,especially discussed the role of melanin during pathogen infection based on our some research.

Animals ; Heart Ventricles ; cytology ; Lipid Bilayers ; Potassium Channels ; Sarcolemma ; physiology ; Swine

The purpose of the present experiment was to observe the morphological characteristics and invasiveness of a transplantable cancer NO 27 (U 27) after serial passages about 20 years. The results were as follows: The morphological characteristics of this tumor strain was low-differentiated carcinoma which were demonstrated by light microscopy and transmission electron microscopy. In the cytoplasm the single irregular distribution of the tensile fibrils and some semi-desmosome between adjacent cells were discovered by transmission electron microscopy. Two types of cancer cells were observed on the surface of the cancer nest by scanning electron microcopy:Ⅰ), There were many microvilli on the surface of the first type cancer cells; 2). The surface of the cancer cells of the second type were more flat sometimes with single small blebs. Many cancer cells had been released from cancer cell clump after 3 days of intramuscular implantation. Later they actively invaded into the spaces between muscle fibers in the form of amebae. Some cancer cells stretched out their filopodia directly in contact with target cells. The degenerative and atrophic changes of muscle tissue appeared in the invasive area of cancer cells. Finally these changes were leading to the disappearance of the entire structure of the muscle with the replacement by cancer tissues.

Objective To explore the effect of miR-9 on the expression of NRP1 and its radiation effects in A549 cells.Methods Bioinformatics was used to analyze the potential binding sites of has-miR-9 and NRP1-3'UTR.The miR-9 sequence was inserted into pcDNA-DEST-47 plasmid to construct the eukaryotic expression vector (pcDNA-DEST-miR-9) and to construct the NRP1 gene 3'UTR luciferase reporter plasmid (pEZX-MT05) at the same time.They were simultaneously transferred into A549 cells for analysis of the regulatory effect of miR-9 on the expression of NRP1.Meanwhile miR-29b was used as a negative control to observe whether or not NRP1 gene was a target of miR-9.After 10 Gy irradiation,the expression of NRP1,and the inhibitory effect of miR-9 on it was confirmed by Western blot assay.The expression of miR-9 was detected by real-time PCR.Results It was found that miR-9 reduced the luciferase activity of NRP1-3'UTR wild plasmid (t =3.906,P ＜ 0.05) but not NRP1-3' UTR mutant plasmid.This luciferase activity was not inhibited by other types of miRNA (miR-29b).The expression of NRP1 protein in A549 cells was decreased after the cells were transfected with miR-9 mimic.After irradiation with dose of 10 Gy,the expression of miR-9 were decreased (t =37.319,P ＜ 0.05) and the expression of NRP1 protein were increased.Conclusions miR-9 regulates the expression of NRP1 by targeting 3'UTR site of NRP1 gene in A549 cells.

Four kinds of colophony were used to isolate the herbicidal substance from the toxin produced by isolate PAM1 of Pythium aphanidermatum, which had herbicidal activity to Digtaria sanguinealis L and the results showed X-5 was the best one for absorbing herbicidal substance among the four kinds of colophony used. Four solvents including 50% ethanol, 95% ethanol, ethyl acetate and acetone were used as eluting solvent and 2 procedures were tested, and the results of growth inhibition and seed germination indicated that the best eluting procedure was procedure 1.

Objective To analyze the effect of high and low dose radiation on the expressions of Th1,Th2 and Th3 /Tr1 related-genes in mice thymocytes and investigate the possible underlying molecular mechanism.Methods ICR mice were randomly divided into low-dose group (0.075 Gy),high-dose group (2.0 Gy) and sham-control group.The mouse thymus tissue was extracted at 16 hours after irradiation and the expressions of Th1-Th2-Th3 related genes were measured by PCR array.Results Eight genes were up-regulated and five genes were down-regulated after low dose radiation (0.075 Gy);while 54 genes were up-regulated and three genes were down-regulated after high dose (2.0 Gy) radiation.These genes included Th1 cell related genes,Th2 cell related genes,Th3/Tr1 cell related genes,Th1/Th2 immune response genes and transcription factor related genes.Low dose radiation induced up-regulation of Stat4 and Socs1 of genes related to the Th1 cells,and it induced down-regulation of IL-4ra,Cebpb,Gata3 and Tgfb3 associated with Th2 and Th3 cells,which lead to Sftpd genes up-regulation of Th1 immune response eventually.The high dose radiation up-regulated all of Th1,Th2 and Th3/Tr related genes and also enhanced the expressions of Cd86,IL-18,IL-10 and Irf4 genes related to Th2 immune response,but it did not alter the gene expression of Th1 immune response.Conclusions Low-dose radiation induces Th1-type immune response,while high doses radiation triggers Th2 type immune response.