1. Role of Smurf1 in bone morphogenetic protein-induced osteogenesis
Academic Journal of Second Military Medical University 2011;32(7):783-785
Bone morphogenetic proteins (BMPs) are confirmed growth factors that can induce osteogenesis. They can bind to the surface receptors of target cells and activate a series of intracellular Smad proteins, which then transduct the signal into cell nuclear; and with the assistance of a series of cofactors, the osteogenic gene expression can be triggered. Endogenous Smurfl plays an inhibitory effect on the above process. This paper reviews the role of Smurf1 in bone morphogenetic protein-induced bone formation.
2.Isolation and Purification of Exopolysaccharide from the Fermentation Broth of Bacillus sp. and Its Antioxidant Effect
Jian-Feng YUAN ; Heng CAI ; Xian-Yang SHAN ; Chuan-Xue XU ; Hong-Gui WAN ;
Microbiology 2008;0(10):-
Based on the Bacillus sp., isolated from Lop Nur Desert, the technology of separation and purification and the antioxidant effect were studied. After centrifugation and vacuum filtration, the deproteinization of supernatant was operated with Sevag reagent. The crude exopolysaccharide (EPS) was obtained by precipitation with ethanol. The optimum conditions for the isolation were as follow: pH 7.0, temperature 4?C, time 1.5 h, and material to ethanol ratio 1: 4. Dissolved in water, the crude EPS was fractional separated on activated carbon column (1.5 cm ? 24 cm), eluted with distilled water, 60% ethanol, 95% ethanol, and the main fraction was collected. Then the EPS was purified on Sephadex G-100 gel column, eluted with NaCl (0.2 mol/L). Fractions (4 mL, each) were also combined according to total sugar by phenol-sulfuric acid method and protein content was determined by Coomassie brilliant blue. The results showed that EPS was relatively homogeneous glycoprotein. The data of antioxidation in vitro showed that the EPS had a high antioxidant activity, which could quench hydroxyl radical, superoxide radical and had antilipid peroxidation activity. All of these indicated that EPS was a good natural antioxidant.
3.Toxic effects of permethrin on HMC3 microglia and its associated mechanism
Wanli ZHANG ; Wenqi SHAN ; Chao CHEN ; Haowei DONG ; Hao YUAN ; Qiuming ZHOU ; Feng TAO ; Heng PENG ; Yajun MA
Journal of Environmental and Occupational Medicine 2024;41(3):267-275
Background Permethrin is a commonly used pyrethroid insecticide and has been found to be potentially neurotoxic. Microglia are innate immune cells in the central nervous system and are involved in the development of a range of neurodegenerative diseases. Objective To observe possible toxic effects of permethrin on human microglia clone 3 (HMC3) in vitro and explore associated mechanism. Methods HMC3 were treated with 0, 10, 25, and 55 μmol·L−1 permethrin for 72 h. Cell cycle and apoptosis were measured using flow cytometry. Cyclin-dependent kinase 1 (CDK1), cyclin-dependent kinase inhibitor 1A (CDKN1A), cyclin B2 (CCNB2), cellular tumor antigen p53 (p53), factor-related apoptosis (FAS), caspase 3 (CASP3), and H2A histone family member X (H2AX) were detected by quantitative real-time PCR (qPCR). The differential genes and enrichment pathways of HMC3 after 0 and 25 μmol·L−1 permethrin treatment was analyzed by RNA sequencing. HMC3 was treated by 0, 10, 25, and 55 μmol· L−1 permethrin for 72 h. The content of nitric oxide (NO) in the supernatant was detected using Griess reagent. The secretion level of interleukin-6 (IL-6) was detected by enzyme linked immunosorbent assay (ELISA). The mRNA expression levels of mitogen-activated protein kinase (MAPK) pathway (including MAPK1, MAPK8, and MAPK14), interleukin-1β (IL-1β), IL-6, and matrix metalloproteinase (MMP) families (including MMP1, MMP2, MMP3, and MMP9) were detected by qPCR. The protein expressions of phosphorylated p38 mitogen-activated protein kinase (p-p38), phosphorylated extracellular signal-regulated kinase (p-ERK), IL-1β, IL-6, and MMP1 were detected by Western blot. Results HMC3 was arrested in G2/M phase after 0, 10, 25, and 55 μmol·L−1 permethrin treatment for 72 h, of which there was a statistically significant difference between the 55 μmol·L−1 permethrin treatment group and the control group (P<0.01), and the mRNA expression of CDKN1A was up-regulated according to the qPCR (P<0.05). There was no statistically significant difference in the proportions of apoptosis between the groups (P>0.05). The RNA sequencing showed that the differential genes were enriched in the MAPK pathway, and the mRNA expressions of MAPK1, MAPK8, and MAPK14 were up-regulated after the permethrin treatment at 55 μmol·L−1 compared to the control group by qPCR (P<0.05). The Western blot revealed that, compared to the control group, the levels of p-p38 and p-ERK were increased after the 10 μmol·L−1 permetrin treatment (P<0.05), the p-ERK level was increased after the 25 μmol·L−1 permetrin treatment (P<0.05), and the p-p38 level was up-regulated after the 55 μmol·L−1 permetrin treatment (P<0.05). The secretion of NO in the supernatant of HMC3 increased after permetrin treatment compared to the control group (P<0.05), the mRNA and protein expressions and the secretion of IL-6 showed an upward trend, the mRNA and protein expressions of IL-1β were up-regulated (P<0.05), and the mRNA and protein expressions of MMP1 were up-regulated in the 25 and 55 μmol·L−1 permethrin groups (P<0.05). Conclusion Permethrin inhibits HMC3 cell proliferation in vitro, induces cell cycle arrest, activates MAPK pathway, and promotes the expression of inflammatory factors IL-1β and MMP1, which may be one of the mechanism of neurotoxicity induced by permethrin.
6.Determination of dimethyl sulfate in workplace air by pre-column derivatization-high performance liquid chromatography
YUAN Jing RONG Wei feng HU Jia wen HE Jia heng MENG Rui bo WU Chuan WU Bang hua
China Occupational Medicine 2022;52(04):425-
Abstract: Objective - -
To establish a pre column derivatization high performance liquid chromatography method for detecting
Methods
dimethyl sulfate (DMS) in workplace air. DMS in workplace air was collected with mercaptopyridine impregnated
(
silicone tube. The derivative of DMS and mercaptopyridine was eluted by mobile phase phase A: water, phase B: acetonitrile,
∶
the volume ratio was 40 60) , and separated with a C18 column, then detected with diode array detector and quantitated by a
Results -
standard curve. The linear range of DMS was 0.17 40.00 mg/L, with the correlation coefficient of 0.999 95. The
detection limit and the lower limit of quantitation were 0.05 and 0.17 mg/L respectively. The minimum detection concentration
and minimum quantitation concentration were 0.02 and 0.04 mg/m³, respectively (air sample volume of 4.5 L, 1.0 mL sample
- - -
solution). The average desorption efficiency was 98.40% 102.00%. The within run and between run relative standard deviations
- -
were 0.61% 3.92% and 1.71% 6.00%, respectively. The samples could be stored at room temperature for at least 14 days.
Conclusion
This method can be used to detect DMS in workplace air.
7.Research progress on detection methods for nitrobenzene compounds in air
WU Fan YUAN Jing HU Jia wen HE Jia heng MENG Rui bo WU Bang hua RONG Wei feng
China Occupational Medicine 2022;52(04):443-
Abstract:
Nitrobenzene compounds (NBCs) are widely used in the world. It has 40 isomers such as nitrobenzene, dinitrobenzene
and nitrotoluene, that are highly toxic and difficult to degrade and can cause harm to human health in different degrees. At pres⁃
ent, there is no unified standard method and occupational exposure limit for the detection of NBCs in the air. In terms of sampling
medium, solid adsorption tube is mostly used for trapping vapor state NBCs, and filter membrane and solid adsorption tube are
mostly used in series for sampling coexist NBCs in vapor state and aerosol state. In the detection methods, gas chromatography
and liquid chromatography are common, and ultraviolet spectrophotometry, Raman spectroscopy, ion migration spectrometry and
some other rapid response methods and technologies are also used in the detection of NBCs. In the detection of NBCs by gas chro⁃
matography, capillary column separation is commonly used, and the main detectors are flame ionization detector, electron capture
detector and mass spectrometry detector. It is of practical significance to establish a method with high sensitivity, strong practica⁃
bility, convenient operation, and can simultaneously collect and detect a variety of NBCs in different states.
8.Chloro-nitrobenzene compounds air sampling tube preparation and determination method
WU fan RONG Wei feng YUAN jing HE Jia heng HU Jia wen MENG Rui bo WU Bang hua YU Ri an
China Occupational Medicine 2022;49(06):697-
Objective - -
To prepare the GDH 5 air sampling tube for simultaneous collection of eight kinds of chloro nitrobenzene
( ) ,
compounds CNBs in the air of workplace and establish a matching determination method using gas chromatography.
Methods - - ,
Eight kinds of CNBs in vapor and aerosol state were collected by self developed GDH 5 air sampling tube desorbed
, , ,
by toluene separated by polysiloxane gas chromatography column detected by microcell electron capture detector and
Results - ( -
quantified by external standard method. It was determined that the air sampling tube was assembled by XAD 2 ion
) - ,
exchange resin and glass fiber filter membrane. The linear range of CNBs was 0.80 240.00 mg/L and the linear correlation
- -
coefficients were greater than 0.999 9. The detection limit was 7.87 13.03 μg/L. The minimum detectable concentration was 0.60
3, - 3( )
1.33 μg/m and the minimum quantitative concentration was 2.00 4.22 μg/m sample 45.00 L . The average desorption
- - (RSD) - , - RSD
efficiency was 101.2% 110.0%. The within run relative standard deviation was 0.8% 4.1% and the between run
- Conclusion -
was 0.3% 5.8%. The samples could be stored for more than 30 days at room temperature. GDH 5 air sampling
tube and its associated determination method can be used for the collection and determination of eight kinds of CNBs in
workplace air.
9.Construction of gene library of Arthrobacter BT801 and isolation & expression of hydantoinase gene.
Shu-Feng HAO ; Wei-Cai ZHANG ; Hong-Jie YUAN ; Heng-Liang WANG ; Liu-Yu HUANG
Chinese Journal of Biotechnology 2003;19(3):281-285
Hydantoinase can be widely used in enzymic production of various amino acids. In order to obtain the hydantoinase genes in Arthrobacter BT801, its chromatosomal DNA is isolated and partialy digested with Sau3A I to collect fragments of about 30kb. Then, this fragment is inserted into the Hpa I and Pst I site of cosmid pKC505. The genomic library was thus constructed by packing in vitro with lambda phage package protein and transfecting E. coli DH5alpha. A positive transformant was selected from the library using thin layer chromatography and other methods. A DNA fragment containing complete hydantoinase genes was sequenced by sub-cloning into pUC18. The gene can express active protein under control of its own promoter and T5 promoter in E. coli. The isolation of the gene established foundition for research and application of the hydantoinase.
Amidohydrolases
;
genetics
;
isolation & purification
;
metabolism
;
Arthrobacter
;
genetics
;
Bacteriophage lambda
;
genetics
;
Chromatography, Thin Layer
;
Cloning, Molecular
;
Electrophoresis, Agar Gel
;
Electrophoresis, Polyacrylamide Gel
;
Escherichia coli
;
genetics
;
metabolism
;
Gene Library
;
Promoter Regions, Genetic
;
genetics
10.Value of magnetic resonance imaging in displaying the parotid gland segments of the facial nerve.
Li-xin DU ; Jian-peng YUAN ; Hua-jian XU ; Heng-feng DU ; Bi-ling LIANG
Journal of Southern Medical University 2010;30(7):1639-1641
OBJECTIVETo evaluate the value of magnetic resonance imaging (MRI) in displaying the parotid gland segments of the facial nerve.
METHODSSixteen volunteers (9 males and 7 females) and 132 surgically confirmed patients with parotid tumors locating in the deep or shallow lobe of the parotid gland (including 89 with benign and 43 with malignant tumors) underwent MRI using T1WI and T2WI. The transverse images were obtained with the plane tilted 35 degrees to the foot, and the coronal images were acquired using conventional scanning.
RESULTSOn transverse T1WI, the parotid gland segments of the facial nerve displayed low signal with arc-shaped curve in the cross-section, showing a symmetrical dot-like low signal in the coronal plane. The facial nerve in 63% of the patients with parotid tumors in the cross-section could be displayed, but in the coronal plane the proportion reached 83%. MRI could accurately reveal the position of the parotid tumors in the deep or shallow lobe of the parotid gland.
CONCLUSIONMRI can show the major portion of the parotid gland segments of the facial nerve and has important value in locating the parotid tumors and displaying the relationship between the tumor and facial nerve.
Adolescent ; Adult ; Aged ; Facial Nerve ; pathology ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Parotid Gland ; innervation ; pathology ; Parotid Neoplasms ; pathology ; Young Adult