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Objective To establish a method for the determination of thallium and its soluble compounds in workplace air using microporous filter membrane sampling and inductively coupled plasma mass spectrometry (ICP-MS). Methods Thallium and its soluble compounds in workplace air were collected using microporous filter membranes, digested with nitric acid, quantified using lutetium internal standard method, and detected by ICP-MS. Results The linear range of thallium was 0.00 to 600.00 μg/L, with the correlation coefficient of 1.000. The detection limit was 0.08 μg/L, and the lower limit of quantification was 0.26 μg/L. The minimum detection concentration and minimum quantitation concentration of thallium of 75.00 L workplace air were 1.0×10-5 and 3.0×10-5 mg/m3, respectively. The minimum detection concentration and minimum quantitation concentration of thallium of 480.00 L workplace air was 2.0×10-6 and 5.0×10-6 mg/m3, respectively. The recovery rate of spiking was 100.82%-103.44%, and the relative standard deviation within- and between-batches was 1.50%-3.32% and 1.32%-3.11%, respectively. The sample could be stored at room temperature for at least 14 days. Conclusion This method can be used for the detection of thallium and its soluble compounds in workplace air.
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Some primary bone tumors are prone to hematogenous metastasis and after that, the therapeutic effect is not that good and prognosis is poor. Circulating tumor cells (CTC) shed from the tumor cells of primary or metastatic focus and then enter into blood circulation. CTC may appear in the early stage of the tumor, which can implant in distant organs to form metastatic sites and self-implant in the primary sites leading to the tumor recurrence; CTC are closely related with the prognosis of patients with tumors. In most primary bone tumors, CTC are heterogeneous compared with primary tumor cells. Studying CTC from various aspects can provide a basis for the early diagnosis and treatment of primary bone tumors. This review summarizes the current researches of CTC in common primary bone tumors, and expects the future of research direction and application practice in clinic.
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OBJECTIVE: To improve the pretreatment method for the detection of lead, manganese and their inorganic compounds in workplace air samples by flame atomic absorption spectrometry. METHODS: In this method, 20.0 mL of 1.0-2.0 mol/L nitric acid solution was used as the digestion solution to digest the microporous membrane sample at 140-160 ℃ to a volume of 0.5-1.0 mL. Samples were cooled and fixed to 10 mL and detected by flame atomic absorption spectrometry method. RESULTS: The lead detection had a good linear relationship in the range of 0.10-3.00 mg/L. The correlation coefficient was 0.999 5, the detection limit and the lower limit of quantification were 0.03 and 0.10 mg/L respectively(calculated by 3 and 10 times of standard deviation respectively). The minimum detection concentration was 0.004 mg/m~3, and the minimum quantitative concentration was 0.010 mg/m~3(collected by 75 L air calculation). The manganese detection had a good linear relationship in the range of 0.05-3.00 mg/L mass concentration. The correlation coefficient was 0.999 8, the detection limit and the lower limit of quantification were 0.015 and 0.05 mg/L respectively(calculated by 3 and 10 times of standard deviation respectively), the minimum detection concentration was 0.002 mg/m~3, and the minimum quantitative concentration was 0.007 mg/m~3(based on collection 75 L air calculation). The recovery rate of standard addition was 97.8%-99.6%, and the relative standard deviation within and between run were 0.4%-2.0% and 0.4%-1.7% respectively. CONCLUSION: The method is simple, the reagent consumption is small, the digestion temperature is low, the precision and accuracy are high. This method is suitable for widespread use.
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OBJECTIVE: To establish a method for testing lithium and its compounds in workplace air by inductively coupled plasma mass spectrometry(ICP-MS). METHODS: Lithium and its compounds in workplace air were collected by microporous filtration membrane. After elution with nitric acid solution in volume fraction of 1.0%, the samples were determined by ICP-MS. RESULTS: The linearity range of lithium mass concentration was 10.00-500.00 μg/L, and the correlation coefficient was 0.999 8. The detection limit was 0.03 g/L and the lower limit of quantitation was 0.10 μg/L. The minimum detection concentration and the minimum quantitative concentration of lithium were 4.0 and 10.0 ng/m~3 respectively. The recovery rate of standard addition was 96.18%-100.91%.The within-run and the between-run relative standard deviation were 1.17%-2.17% and 0.89%-1.54% respectively. Lithium and its compound samples could be stored at room temperature for at least 28 days. CONCLUSION: The method could be used for detection of lithium and its compounds in workplace air.
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Malignant bone tumors, one of the most common bone tumors includes osteosarcoma, Ewing's sarcoma, multiple myeloma, and metastatic bone tumors etc. These tumors are often accompanied by distant metastatic lesions at time of diagnosis, leading to low 5-year survival rates. At present, the use of biomarkers for early detection in order to facilitate early treatment are very limited. Therefore, most medical researchers are exploring the roles of exosomes in detecting malignant bone tumors. Exosomes are extracellular microvesicles secreted by different types of cells, which exist in a variety of body fluids. They are new intercellular information carriers that play important physiological roles. Current literature have reported that the RNA contained in exosomes (such as mRNA, miRNAs, lncRNAs and circRNAs) play important roles in the incidence as well as development of malignant bone tumors. However, the previous studies mostly focused on the roles of exosomal RNA in malignant bone tumor diseases, in tumor cell proliferation or apoptosis, transfers, evasion of immune surveillance and chemotherapy drug resistance etc. However, exosomal RNAs may function in the whole process of the disease progression via regulation networks. Our review of existing literature revealed that exosomal RNAs affacted the proliferation, metastasis, immune evasion and drug resistance of five common malignant bone tumors; Osteosarcoma, Ewing sarcoma, Chondrosarcoma, multiple myeloma, and metastatic bone tumors. Therefore, by elucidating on the mechanism of exosomal RNAs in the occurrence and development of malignant bone tumors, this study, could provide new ideas for early diagnosis, concomitant diagnosis, efficacy estimation (chemotherapy, radiotherapy and immunotherapy, etc.) as well as assessing the prognosis of malignant bone tumors.
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Objective:To investigate the clinical significance of dynamic analysis of plasma brain natriuretic peptide in patients with dilated cardiomyopathy with chronic heart failure.Methods:Ninety patients with dilated cardiomyopathy with chronic heart failure admitted into our hospital firom March 2012 to March 2016 were divided into group A (20 cases),group B (38 cases),and group C (32 cases) according to the NYHA grading.The plasma BNP levels and LVEF,LA,LVEDD,and LVESD in the three groups were detected and compared.The correlation of plasma BNP and cardiac function and ultrasonic cardiogram indexes were analyzed.And the capability of plasma BNP and LVEF in diagnosis of patients were analyzed and compared.Results:The plasma BNP level in group C was markedly higher than that of group A and group B (P＜0.05),and that in group B was much higher than that of group A (P＜0.05).And LA in group C was significantly higher than that of group A (P＜0.05),while differences in LVEF,LVEDD,and LVESD were not obvious (P＞0.05).The plasma BNP was positively correlated to NYHA grading,but had no significant correlation with the LVEF,LVEDD,LVESD,and LA (P＞0.05).Based on results of receiver operating characteristic curve analysis,plasma BNP =523.5 pg/mL was the threshold value for identification of patients with NYHA Ⅲ and Ⅳ (AUC=0.901,P＜0.001),while LVEF had not the capability (AUC=0.392,P=0.276).Conclusion:Detection of plasma BNP level had important clinical significance on diagnosis,screening and cardiac functional grading of patients with dilated cardiomyopathy with chronic heart failure.
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BACKGROUND: Surface roughness of implants can directly influence cellular proliferation, differentiation, and gene expression. OBJECTIVE: To observe the early attachment of periodontal ligament cells (PDLCs) to pure titanium with different surface roughness levels, and to study the effect of surface performance on cell differentiation. DESIGN, TIME AND SETTING: Randomized controlled observation/multi-sample comparison study, which was performed at Center of Science and Technology, Gannan Medical College between January 2005 and July 2006. MATERIALS: Pure titanium stick was cut into pieces, of 10 mm diameter and 2 mm thickness, using cutting-off machine, and there were 24 sections in total. Then, the titanium sections were randomly divided into four groups: simple mechanical processing, nitric acid processing, sand blasting processing, and combination group, with 6 sections per group. METHODS: TR240 portable-type surface roughness meter was used in this study. In the simple mechanical processing group, sections were scoured by sand paper alone; in the nitric acid processing group, sections were etched with 65% HNO3 for 1 hour at 100 ℃ after scoured by sand paper; in the sand blasting processing group, sections were sandblasted by 100 μ m AI203 after scoured by sand paper; in the combination group, sections were etched with 65% HNO3 for I hour at 100～C after scoured by sand paper and sandblasted by 100 μ m Al2O3. MAIN OUTCOME MEASURES: Samples were maintained in DMEM for 30 minutes, and the third-passage cells were inoculated. Then, titanium sections were taken out at different time points of 30, 60, 120, 240 minutes, 1, 3, and 7 days. Surface roughness and early attachment of PDLCs were detected under fluorescent microscope. RESULTS: O Quantitative analysis: Surface roughness was (599.5±8.3) nm in the simple mechanical processing group, (406.5 +4.6) nm in the nitric acid processing group, (358.8±11.8) nm in the sand blasting processing group, and (8.7±2.0) nm in the combination group. On the other hand, surface roughness in the simple mechanical processing group was significantly higher Fluorescence observation exhibited that number of PDLCs attaching to pure titanium surface was increased, and the proliferation was greater with the time passing by. in addition, surface roughness of pure titanium was positively associated with number of PDLCs. CONCLUSION: The lighter the surface roughness is, the more the early attachment of PDLCs is, benefiting for cell adhesion and proliferation.
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BACKGROUND: The investigation of culturing, passaging and establishing human limbal stem cells can strengthen the recognition of the stem cells and provide the enough cellular reserve for the basic and clinical research of limbal stem cell transplantation.OBJECTIVE: To explore a method of pessaging and establishing cell line of human limbal stem cells cultured in vitro.DESIGN: Randomized controlled observation.SETTING: Gannan Medical College.MATERIALS: The experiment was performed at Scientific Center of Gannan Medical College and the National Key Laboratory of Ophthalmology Hospital Affiliated to Sun Yat-Sen University from June 2003 to April 2004. Fresh human limbus corneae were isolated from two healthy donors. Procedures were performed according to the informed consent of the donors. Main reagents contained RPMI-1640 (Sigma R8755, containing L-glutamine) and 200 g/L fetal calf serum (FCS) (Gibco 16140-071). DMEM medium, chondroitin sulfatase and human epidermal growth factor (hEGF) were purchased from Sigma Co. USA; HEPES and DMSO were bought from Gibco, USA; 100% glycerinum was purchased from Yunjia Huangpu Pharmaceutical Product Limited Company, PRC; glutaraldehyde was bought from E.Merk, Germany; Alcohol, chlorhydric acid, acetone and methyl aldehyde were purchased from Beijing Chemical Agent Company, PRC; 0.25% parenzyme was bought from Shanghai Xinhua Pharmaceutical Factory, PRC.Above-mentioned reagents were analytical pure grade.METHODS: After digestion, human limbal tissues in limbal basilar part with an abundant pigment were cultured in the culture flask containing RPMI-1640 and 200 g/L FCS and in culture dish containing amniotic extracellular matrix (AECM) as the cultural supporter. Primary and passage cells were observed under light microscope and scanning electron microscope (SEM). The revival ratio of stem cell refrigeration of every generation was calculated by the trypanblau exclusion experiment.MAIN OUTCOME MEASURES: ① Observational results of limbal stem cells during the primary culture and serial subcultivation in vitro, and ② revival ratio of stem cell refrigeration.RESULTS: ①Findings of primary culture: Most limbal stem cells in the culture flask had the adherence and were arrayed uniformly sparsely to form monolayer and adhered to the bottom of culture flask under the inverted phase contrast microscope after 1-day culture. ② Findings of serial subcultivation: After human epidermal growth factor (hEGF) was added into the second passage, cells were scattered into the monolayer and adhered to grow quickly.Morphological variability of all the cells increased obviously when passage the 30th generation. The cellular volume was obviously increasing, and the round or irregular round cells gathered together. The 33rd generation human limbal stem cells still could vigorously differentiate, proliferate and grow in ACEM. ③ The revival ratio of stem cell refrigeration was 82.2%.CONCLUSION: The human limbal stem cell lines were preliminarily established by culturing and freezing the cells of 33 generations in vitro. The human limbal stem cell lines preferred to grow in the culture dish containing AECM as the cultural supporter.
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BACKGROUND: Stromal cell-derived factor 1 (SDF1), a potential inhibitor of infection by lymphophilic HIV-1 strains, can help to block the pathway of HIV-1 invasion into the human body.OBJECTIVE: Genotype and polymorphism of SDF1-3 'A allele associated with HIV-1 infection were investigated in She Ethnic Group in the south of China so as explore the possible causes of uninfection by HIV-1 strains among this population.DESIGN: Single sample study.SETTING: Department of Biochemistry and Molecular Biology, Gannan Medical College.PARTICIPANTS: Totally 186 She Ethnic subjects without HIV-1 infection collected randomly from those whose three generations belonged to She Ethnic Group, and inhabited in Qianshan County of Jiangxi Province,Ningde area of Fujian Province and Jingning She County of Zhejiang Province, from January to December 1995.METHODS: The whole blood samples from 186 She Ethnic subjects were collected randomly, and then their genomic DNA samples were extracted respectively. Allelic polymorphism was examined by the polymerase chain reaction and restriction-fragment-length polymorphisms (PCR-RFLP).MAIN OUTCOME MEASURES: The distribution of SDF1-3'A allele in She Ethnic Group in the south of China.RESULTS: The data of 186 She Ethnic subjects entered the result analysis without any loss in the midway. The frequency of SDF1-3 'A allele in She Ethnic Group samples was 19.6%, and the allelic distribution of the gene was in accordance with Hardy-Weinberg equilibrium. No difference was found between male and female individuals.CONCLUSION: The frequency of SDF1-3 'A allele of She Ethnic Group in the south of China was similar to that of Dai Nationality in Yunnan.Based on its slow-down effect on clinical course of AIDS, the mutation of SDF1-3'A is significant in the prevention and treatment of AIDS in She Ethnic Group in the south of China.