Objective - To analyze the relationship between cobalt level of post shift urine and individual exposure level of ， cobalt and its compounds in cobalt exposed workers and to explore the feasibility of using urine cobalt as a biomarker. Methods - A total of 148 occupational cobalt exposed workers from a new material company were selected as the exposed ， - - group and 44 non occupational cobalt exposed workers from the company were selected as the control group using the typical sampling method. The exposure concentration of time weighted average of cobalt and its compounds in the workplace air of the - two groups was determined by inductively coupled plasma mass spectrometry as the individual exposure level. The cobalt levels - - of pre shift and post shift urinary samples of the two groups were detected by this method. The linear relationship between the - cobalt level of post shift urine and the individual exposure level of cobalt and its compounds in the air of the workplace was Results - 3 analyzed. The individual exposure level of cobalt and its compounds in the exposed group was 1.10 131.71 μg/m with （M） 3 the median of 12.23 μg/m. No cobalt and its compounds were detected in the workplace air in the control group. The cobalt - - levels of pre shift and post shift urines in exposed group were higher than those in the control group at the same time point （M： vs ， vs ， P ） - - 1.54 0.56 μg/L 8.77 0.83 μg/L all <0.01 . The cobalt level of post shift urine was higher than that in pre shift （M： vs ，P ）， urine in the exposed group 8.77 1.54 μg/L <0.01 and it was positively correlated with the individual exposure level （ ，P ） ， of cobalt and its compounds Spearman correlation coefficient=0.86 <0.01 . After common logarithm conversion the linear regression equation of the cobalt level of post shift urine and the common logarithm of individual exposure level of cobalt and （x） ：ŷ x（ ；F ， its compounds in the exposed group was as follows = −0.178 + 0.988 coefficient of determination=0.72 =374.75 P ；t ， P ） Conclusion - <0.01 = - 19.36 <0.01 . There was a linear correlation between cobalt level of post shift urine and occupational cobalt exposure level of cobalt exposed workers. Urinary cobalt can be used as a biomarker of occupational cobalt

OBJECTIVE: To establish a method for testing tetrahydrofuran( THF) in workplace air by solvent desorption gas chromatography. METHODS: The air samples were collected by activated carbon tube,desorbed with carbon disulfide solution,then separated by capillary column and detected by flame ionization detector. RESULTS: The linearity range of THF concentration was 1. 78-8 892. 00 mg / L,and the correlation coefficient was 0. 999 9. The minimum detection limit of THF was 0. 09 mg / m3. The minimum quantitative concentration was 0. 27 mg / m3( 3. 00 L air collection). The average desorption efficiency of THF was 94. 29%-96. 46% when placed overnight at the room temperature. The within-run and the between-run relative standard deviation were 0. 30%-0. 91% and 0. 66%-1. 23% respectively. THF sample could be stored at room temperature for at least 8 days. CONCLUSION: The method could be widely applied in sampling and detection of THF in workplace air.

OBJECTIVETo explore the mechanism of miR-124 inhibiting the proliferative activity of prostate cancer PC3 cells.

METHODSLuciferase reporter gene assay was used to examine the specific binding ability of miR-124 to PKM2 mRNA 3'-UTR. After miR-124 was transfected mimic to PC3 cells, the expression levels of PKM2 mRNA and protein were detected by real-time fluorescence quantitative PCR (qRT-PCR) and Western blot, respectively. The effects of miR-124 mimic and PKM2 siRNA on the proliferative activity of the PC3 cells were determined by MTT assay.

RESULTSThe expressions of PKM2 mRNA and protein were upregulated (5.12 +/- 0.35) times and (4.05 +/- 0.20) times respectively in the PC3 cells as compared with those in the RWPE-1 cells (P < 0.05). Luciferase reporter gene assay demonstrated that miR-124 targeted PKM2 3'-UTR. At 24 hours after transfection with miR-124 mimic, the PKM2 protein expression in the PC3 cells was downregulated (0.16 +/- 0.04) times (P < 0.05), while the PKM2 mRNA level was not changed significantly (P > 0.05), as compared with the control group. MTT assay showed that both miRNA-124 mimic and PKM2 siRNA could inhibit the proliferation of the PC3 cells, but the former exhibited a greater inhibitory effect than the latter. After transfection with miR-124 mimic and PKM2 siRNA, the cell growth rates were (66.20 +/- 5.10)% vs (82.10 +/- 6.35)% at 24 hours (P < 0.05) and (49.34 +/- 2.37)% vs (70.10 +/- 5.80)% at 48 hours (P < 0.05).

CONCLUSIONmiR-124 can suppress the proliferation of PC3 cells by regulating the PKM2 gene.

Carrier Proteins ; genetics ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; genetics ; Humans ; Male ; Membrane Proteins ; genetics ; metabolism ; MicroRNAs ; genetics ; Prostatic Neoplasms ; genetics ; metabolism ; pathology ; Thyroid Hormones ; genetics ; metabolism ; Transfection

In this study we determined whether or not 5-hydroxytryptamine (5-HT) has an effect on the pacemaker activities of interstitial cells of Cajal (ICC) from the mouse small intestine. The actions of 5-HT on pacemaker activities were investigated using a whole-cell patch-clamp technique, intracellular Ca2+ ([Ca2+]i) analysis, and RT-PCR in ICC. Exogenously-treated 5-HT showed tonic inward currents on pacemaker currents in ICC under the voltage-clamp mode in a dose-dependent manner. Based on RT-PCR results, we found the existence of 5-HT2B, 3, 4, and 7 receptors in ICC. However, SDZ 205557 (a 5-HT4 receptor antagonist), SB 269970 (a 5-HT7 receptor antagonist), 3-tropanylindole - 3 - carboxylate methiodide (3-TCM; a 5-HT3 antagonist) blocked the 5-HT-induced action on pacemaker activity, but not SB 204741 (a 5-HT2B receptor antagonist). Based on [Ca2+]i analysis, we found that 5-HT increased the intensity of [Ca2+]i. The treatment of PD 98059 or JNK II inhibitor blocked the 5-HT-induced action on pacemaker activity of ICC, but not SB 203580. In summary, these results suggest that 5-HT can modulate pacemaker activity through 5-HT3, 4, and 7 receptors via [Ca2+]i mobilization and regulation of mitogen-activated protein kinases.
Animals ; Flavonoids ; Gastrointestinal Motility ; Imidazoles ; Interstitial Cells of Cajal ; Intestine, Small ; Mice ; Mitogen-Activated Protein Kinases ; para-Aminobenzoates ; Patch-Clamp Techniques ; Phenols ; Pyridines ; Receptor, Serotonin, 5-HT2B ; Receptors, Serotonin ; Receptors, Serotonin, 5-HT4 ; Serotonin ; Sulfonamides

We studied whether nitric oxide (NO) and hydrogen sulfide (H2S) have an interaction on the pacemaker activities of interstitial cells of Cajal (ICC) from the mouse small intestine. The actions of NO and H2S on pacemaker activities were investigated by using the whole-cell patch-clamp technique and intracellular Ca2+ analysis at 30degrees C in cultured mouse ICC. Exogenously applied (+/-)-S-nitroso-N-acetylpenicillamine (SNAP), an NO donor, or sodium hydrogen sulfide (NaHS), a donor of H2S, showed no influence on pacemaker activity (potentials and currents) in ICC at low concentrations (10 microM SNAP and 100 microM NaHS), but SNAP or NaHS completely inhibited pacemaker amplitude and pacemaker frequency with increases in the resting currents in the outward direction at high concentrations (SNAP 100 microM and NaHS 1 mM). Co-treatment with 10 microM SNAP plus 100 microM NaHS also inhibited pacemaker amplitude and pacemaker frequency with increases in the resting currents in the outward direction. ODQ, a guanylate cyclase inhibitor, or glibenclamide, an ATP-sensitive K+ channel inhibitor, blocked the SNAP+NaHS-induced inhibition of pacemaker currents in ICC. Also, we found that SNAP+NaHS inhibited the spontaneous intracellular Ca2+ ([Ca2+]i) oscillations in cultured ICC. In conclusion, this study describes the enhanced inhibitory effects of NO plus H2S on ICC in the mouse small intestine. NO+H2S inhibited the pacemaker activity of ICC by modulating intracellular Ca2+. These results may be evidence of a physiological interaction of NO and H2S in ICC for modulating gastrointestinal motility.
Animals ; Gastrointestinal Motility ; Glyburide ; Guanylate Cyclase ; Humans ; Hydrogen ; Hydrogen Sulfide ; Interstitial Cells of Cajal ; Intestine, Small ; Mice ; Nitric Oxide ; Patch-Clamp Techniques ; Sodium ; Sulfides ; Tissue Donors

BACKGROUND/AIMS: Capsaicin (8-methyl-N-vanillyl-6-ninenamide), a compound found in hot peppers, has been reported to have different physiological actions on different cell types. Not much work has been done about the effect of capsaicin on the function of interstitial cells of Cajal (ICC). In the present study, we examined the action of external application of capsaicin on pacemaker activity in the cultured ICC from the small intestine of mouse. METHODS: We investigated the effect of capsaicin on pacemaker currents in cultured ICC from the small intestine of mouse using a whole cell patch-clamp technique and Ca2+-imaging analysis. RESULTS: When capsaicin was applied externally to the pacemaker generating ICC, it completely inhibited the pacemaker potential under current-clamp mode (I = 0) and the pacemaker current under voltage-clamp mode at a -70 mV of holding potentials. The effect of capsaicin on pacemaker activity in ICC was shown dose dependently. The effect of capsaicin was not through the transient receptor potential of the vanilloid type 1 (TRPV1) channel as capsazepine did not block the effect of capsaicin. L-NAME, an inhibitor of nitric oxide synthase, also did not block the capsaicin-induced effects. When the action of capsaicin was examined in the intracellular calcium oscillation, it completely abolished the calcium oscillation. CONCLUSIONS: These results prove that the capsaicin has the inhibitory effects on the ICC which is carried out neither through TRPV channel nor the nitric oxide production. Intracellular Ca2+ was also an important target for actions of capsaicin on ICC.
Animals ; Calcium Signaling ; Capsaicin ; Gastrointestinal Motility ; Interstitial Cells of Cajal ; Intestine, Small ; Mice ; NG-Nitroarginine Methyl Ester ; Nitric Oxide ; Nitric Oxide Synthase ; Patch-Clamp Techniques

BACKGROUNDThis retrospective study evaluated the diagnostic accuracy of 2-(F18)-fluoro-2-deoxy-D-glucose-positron emission tomography ((18)F-FDG-PET)/computed tomography (PET/CT) in the preoperative diagnosis of metastatic mediastinal and hilar lymph node in patients with non-small-cell lung cancer (NSCLC).

METHODSA total of 39 patients received preoperative (18)F-FDG PET/CT and the postoperative biopsy. We compared preoperative PET/CT scan results with corresponding intraoperative histopathalogic findings in 39 NSCLC patients. The sensitivity, specificity, accuracy, positive and negative predictive value of (18)F-FDG PET/CT were assessed.

RESULTSHistopathologic examination confirmed metastasis in 57 out of the 208 excised lymph nodes; 23 of the 57 nodes were mediastinal and hilar lymph nodes. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of PET/CT in the preoperative diagnosis of mediastinal lymph node metastasis in NSCLC patients were 65%, 96.8%, 92%, 78.5% and 90%, respectively.

CONCLUSIONSPET/CT scan showed good accuracy in the preoperative diagnosis of mediastinal and hilar lymph node metastasis in the patients with NSCLC. We recommend that PET/CT scanning be used as a first-line evaluation tool for tumor diagnosis, therapy evaluation and follow-up.

Adult ; Aged ; Carcinoma, Non-Small-Cell Lung ; diagnosis ; Female ; Fluorodeoxyglucose F18 ; Humans ; Lung Neoplasms ; diagnosis ; Lymph Nodes ; pathology ; Lymphatic Metastasis ; diagnosis ; Male ; Middle Aged ; Neoplasm Staging ; methods ; Positron-Emission Tomography ; methods ; Retrospective Studies

The effects of (-)-epigallocatechin gallate (EGCG) on pacemaker activities of cultured interstitial cells of Cajal (ICC) from murine small intestine were investigated using whole-cell patch-clamp technique at 30degrees C and Ca2+ image analysis. ICC generated spontaneous pacemaker currents at a holding potential of -70 mV. The treatment of ICC with EGCG resulted in a dose-dependent decrease in the frequency and amplitude of pacemaker currents. SQ-22536, an adenylate cyclase inhibitor, and ODQ, a guanylate cyclase inhibitor, did not inhibit the effects of EGCG. EGCG-induced effects on pacemaker currents were not inhibited by glibenclamide, an ATP-sensitive K+ channel blocker and TEA, a Ca2+-activated K+ channel blocker. Also, we found that EGCG inhibited the spontaneous [Ca2+]i oscillations in cultured ICC. In conclusion, EGCG inhibited the pacemaker activity of ICC and reduced [Ca2+]i oscillations by cAMP-, cGMP-, ATP-sensitive K+channel-independent manner.
Adenine ; Adenylyl Cyclases ; Animals ; Gastrointestinal Motility ; Glyburide ; Guanylate Cyclase ; Interstitial Cells of Cajal ; Intestine, Small ; Mice ; Patch-Clamp Techniques ; Tea

The scholars at home and abroad pay great attention to the studies of specificities of acupoints, but the studies were superficial and non-systemic because of lacking to application of modern sciences and technology. There are not persuasive conclusive achievements for the specificities of acupoints and the key factors influencing the effect of acupuncture. The study of the specificities of acupoints should be concentrate on the diseases for which acupuncture and moxibustion are effective. And multiple modern sciences and techniques should be adopted to resolve the key problems about biological and physical characteristics, pathological response, effects and law of compatibility of acupoints usually selected for the diseases, and then to create the model of the theory about the specificities of acupoints and to richen and develop the theory of the specificity of acupoints.
Acupuncture Points ; Humans ; Research

OBJECTIVETo investigate the FDG uptake characteristics, the factors affecting 18F-FDG uptake and the extra CT diagnostic value of 18F-FDG PET/CT scan in the malignant tumor with false negative 18F-FDG PET image.

METHODSThe data of PET/CT image in 17 patients with various kinds of cancers were reviewed and analyzed by visual observation and semi-quantity analysis ( SUV). The results were compared with the CT and histopathological diagnosis, respectively.

RESULTSOf 6 well-differentiated HCC patients confirmed by histopathological diagnosis, one had two lesions in the right lobe of the liver. One of these two lesions showed low FDG uptake on 18F-FDG PET scan and low density on CT scan. The other one was not shown on either 18F-FDG PET or plain CT scan. But on enhanced CT scan, these two lesions were found to be inhomogeneous with high density at arterial phase. The false negative 18F-FDG PET images of one gastric signet ring cell carcinoma in the gastric fundus with right adnexa metastasis, 3 renal cell carcinoma, one greater omentum and peritoneal metastatic adenocarcinoma and one well-differentiated prostate cancer were caused by normal physical uptake in the digestive tract or FDG retention in the urinary system due to normal excretion. The size of three metastases was smaller than or equal to 1 cm in diameter, however, two primary lesions of these metastases showed high FDG uptake and only one was negative on either 18F-FDG PET or CT scan. In this series, 68.8% of the primary tumors and 66.7% of metastases were found to show abnormal density on CT scan, and 31. 2% of the primary tumors and 33. 3% of metastases were not detectable on either PET or CT images.

CONCLUSIONFalse negative 18F-FDG PET in malignant tumor may be correlated with the pathologic type, differentiation degree and the lesion size. Combining CT information with PET or paying attention to the scan methods during 8 F-FDG PET examination may reduce the rate of false negative 18F-FDG PET diagnosis in various kinds of malignant tumors.

Adenocarcinoma ; diagnostic imaging ; secondary ; Adult ; Aged ; Carcinoma, Hepatocellular ; diagnostic imaging ; pathology ; Carcinoma, Renal Cell ; diagnostic imaging ; pathology ; Carcinoma, Signet Ring Cell ; diagnostic imaging ; pathology ; False Negative Reactions ; Female ; Fluorodeoxyglucose F18 ; Humans ; Kidney Neoplasms ; diagnostic imaging ; pathology ; Liver Neoplasms ; diagnostic imaging ; pathology ; Male ; Middle Aged ; Omentum ; diagnostic imaging ; Peritoneal Neoplasms ; diagnostic imaging ; secondary ; Positron-Emission Tomography ; methods ; Radiographic Image Enhancement ; Stomach Neoplasms ; diagnostic imaging ; pathology ; Tomography, X-Ray Computed