1.Phase Separation of Biomacromolecules and Its Important Role in Transcriptional Regulation
Xiang-Dong ZHAO ; Le WANG ; Lu-Jie MA ; De-Bao XIE ; Meng-Di GAO ; Ya-Nan MENG ; Fan-Li ZENG
Progress in Biochemistry and Biophysics 2024;51(4):743-753
Cells not only contain membrane-bound organelles (MBOs), but also membraneless organelles (MLOs) formed by condensation of many biomacromolecules. Examples include RNA-protein granules such as nucleoli and PML nuclear bodies (PML-NBs) in the nucleus, as well as stress granules and P-bodies in the cytoplasm. Phase separation is the basic organizing principle of the form of the condensates or membraneless organelles (MLOs) of biomacromolecules including proteins and nucleic acids. In particular, liquid-liquid phase separation (LLPS) compartmentalises and concentrates biological macromolecules into liquid condensates. It has been found that phase separation of biomacromolecules requires some typical intrinsic characteristics, such as intrinsically disordered regions, modular domains and multivalent interactions. The phase separation of biomacromolecules plays a key role in many important cell activities. In recent years, the phase separation of biomacromolecules phase has become a focus of research in gene transcriptional regulation. Transcriptional regulatory elements such as RNA polymerases, transcription factors (TFs), and super enhancers (SEs) all play important roles through phase separation. Our group has previously reported for the first time that long-term inactivation or absence of assembly factors leads to the formation of condensates of RNA polymerase II (RNAPII) subunits in the cytoplasm, and this process is reversible, suggesting a novel regulatory model of eukaryotic transcription machinery. The phase separation of biomacromolecules provides a biophysical understanding for the rapid transmission of transcriptional signals by a large number of TFs. Moreover, phase separation during transcriptional regulation is closely related to the occurrence of cancer. For example, the activation of oncogenes is usually associated with the formation of phase separation condensates at the SEs. In this review, the intrinsic characteristics of the formation of biomacromolecules phase separation and the important role of phase separation in transcriptional regulation are reviewed, which will provide reference for understanding basic cell activities and gene regulation in cancer.
2.Stepwise treatment strategy for spontaneous osteonecrosis of the medial femoral condyle of the knee joint
Jianke PAN ; Meiping YANG ; Yanhong HAN ; Di ZHAO ; Hetao HUANG ; Houran CAO ; Jun LIU ; Minghui LUO ; Xiang LI ; Hongyun CHEN ; Weiyi YANG
Chinese Journal of Tissue Engineering Research 2024;28(12):1907-1913
BACKGROUND:Currently,there have been a variety of conservative and surgical treatment plans for spontaneous osteonecrosis of the knee,achieving excellent results.However,a broad consensus on indication and guide of surgical treatment has not been announced.In clinical practice,there is still a misunderstanding that unicondylar replacement or total knee arthroplasty should be performed upon the discovery of spontaneous osteonecrosis of the knee,while an urgent need for universal access to the concept of stepwise therapy. OBJECTIVE:To summarize and find the factors leading to the poor effect of conservative treatment in spontaneous osteonecrosis of the knee,which occurred on the medial femoral condyle,from the literature and clinical cases,at the same time,combined with the Koshino stage,to propose the strategy of stepwise spontaneous osteonecrosis of the knee treatment on the medial femoral condyle. METHODS:A systematic search of the literature database was conducted to summarize the factors leading to poor outcomes of conservative treatment in spontaneous osteonecrosis of the medial femoral condyle.Meanwhile,according to the Clinical&Health Records for analytics&Sharing system,the cases receiving conservative and surgical treatment in spontaneous osteonecrosis of the medial femoral condyle in the Department of Orthopedics of Guangdong Provincial Hospital of Chinese Medicine from January 2017 to January 2023 were analyzed retrospectively,then the causes of success and failure in typical cases were summarized and analyzed. RESULTS AND CONCLUSION:(1)Early diagnosis and treatment of spontaneous osteonecrosis of the knee were very important for prognosis.For sudden knee pain in some patients,if no obvious abnormality was found in the X-ray examination,and the symptoms persisted and could not be relieved for more than 1 week,an MRI examination was recommended to detect early spontaneous osteonecrosis of the knee.(2)The X-ray images of Koshino stage 1 and stage 2 of spontaneous osteonecrosis of the medial femoral condyle were difficult to be distinguished,which needed to be probed by MRI.MRI images of Koshino stage 1 were mainly characterized by bone marrow edema,and an osteonecrosis area with a clear boundary was not formed,while MR images of Koshino stage 2 showed a necrotic area with a clear boundary.(3)Five factors leading to the poor effect of conservative treatment on spontaneous osteonecrosis of the medial femoral condyle were summarized:a.The necrotic area was>5 cm2;b.The necrotic area accounted for more than 40%of the condyle;c.relative compression percentage of medial meniscus≥33%(with or without medial meniscus injury and subchondral bone marrow edema);d.MRI depth of necrotic area(anterior-posterior diameter of sagittal necrotic area)>20 mm;e.varus deformity of lower limb>6°.(4)Conservative treatment of spontaneous osteonecrosis of the knee in Koshino stage 1 was good.For spontaneous osteonecrosis of the knee in Koshino stage 2,conservative treatment was preferred or combined with drilling decompression.If there was no relief or improvement of symptoms or in MRI after 3 months,while the patient had any of the previous five factors,then knee preservation surgery should be considered.For spontaneous osteonecrosis of the knee in Koshino stage 3 and stage 4,knee preservation surgery should be selected based on the previous five factors,including age,gender and activity level of the patient.Total knee arthroplasty was used for spontaneous osteonecrosis in Koshino stage 4,which was associated with symptomatic patellofemoral arthritis,valgus alignment,or necrotic area,which greatly affected the stability of unicondyle prosthesis.
3.Mechanism of total flavonoids of Rhododendra simsii in alleviating ischemic brain injury.
Chen-Chen JIANG ; Lei SHI ; Xin-Ya ZHAO ; Hui ZHANG ; Zi-Xu LI ; Jia-Jun LU ; Yu-Xiang HE ; Di CAO ; Hao-Ran HU ; Jun HAN
China Journal of Chinese Materia Medica 2023;48(2):455-464
This study explores the effect of total flavonoids of Rhododendra simsii(TFR) on middle cerebral artery occlusion(MCAO)-induced cerebral injury in rats and oxygen-glucose deprivation/reoxygenation(OGD/R) injury in PC12 cells and the underlying mechanism. The MCAO method was used to induce focal ischemic cerebral injury in rats. Male SD rats were randomized into sham group, model group, and TFR group. After MCAO, TFR(60 mg·kg~(-1)) was administered for 3 days. The content of tumor necrosis factor-α(TNF-α), interleukin-1(IL-1), and interleukin-6(IL-6) in serum was detected by enzyme-linked immunosorbent assay(ELISA). The pathological changes of brain tissue and cerebral infarction were observed based on hematoxylin and eosin(HE) staining and 2,3,5-triphenyltetrazolium chloride(TTC) staining. RT-qPCR and Western blot were used to detect the mRNA and protein levels of calcium release-activated calcium channel modulator 1(ORAI1), stromal interaction molecule 1(STIM1), stromal intera-ction molecule 2(STIM2), protein kinase B(PKB), and cysteinyl aspartate specific proteinase 3(caspase-3) in brain tissues. The OGD/R method was employed to induce injury in PC12 cells. Cells were randomized into the normal group, model group, gene silencing group, TFR(30 μg·mL~(-1)) group, and TFR(30 μg·mL~(-1))+gene overexpression plasmid group. Intracellular Ca~(2+) concentration and apoptosis rate of PC12 cells were measured by laser scanning confocal microscopy and flow cytometry. The effect of STIM-ORAI-regulated store-operated calcium entry(SOCE) pathway on TFR was explored based on gene silencing and gene overexpression techniques. The results showed that TFR significantly alleviated the histopathological damage of brains in MCAO rats after 3 days of admini-stration, reduced the contents of TNF-α, IL-1, and IL-6 in the serum, down-regulated the expression of ORAI1, STIM1, STIM2, and caspase-3 genes, and up-regulated the expression of PKB gene in brain tissues of MCAO rats. TFR significantly decreased OGD/R induced Ca~(2+) overload and apoptosis in PC12 cells. However, it induced TFR-like effect by ORAI1, STIM1 and STIM2 genes silencing. However, overexpression of these genes significantly blocked the effect of TFR in reducing Ca~(2+) overload and apoptosis in PC12 cells. In summary, in the early stage of focal cerebral ischemia-reperfusion injury and OGD/R-induced injury in PC12 cells TFR attenuates ischemic brain injury by inhibiting the STIM-ORAI-regulated SOCE pathway and reducing Ca~(2+) overload and inflammatory factor expression, and apoptosis.
Animals
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Male
;
Rats
;
Apoptosis
;
Brain Ischemia/metabolism*
;
Caspase 3
;
Interleukin-1
;
Interleukin-6
;
Rats, Sprague-Dawley
;
Reperfusion Injury/metabolism*
;
Tumor Necrosis Factor-alpha/genetics*
;
Flavonoids/pharmacology*
;
Rhododendron/chemistry*
4.Shikonin induces hepatocellular carcinoma cell apoptosis by suppressing PKM2/PHD3/HIF-1α signaling pathway.
Huan Huan ZHANG ; Zhuo CHEN ; Xiang Di ZHAO ; Qiang HUO ; Xiu CHENG
Journal of Southern Medical University 2023;43(1):92-98
OBJECTIVE:
To investigate the mechanism of shikonin-induced death of human hepatocellular carcinoma SMMC-7721 cells.
METHODS:
Cultured SMMC-7721 cells and normal hepatocytes (L-02 cells) were treated with 4, 8, or 16 μmol/L shikonin, and the changes in cell viability was assessed using MTT assay. The levels of ATP and lactic acid in the cell cultures were detected using commercial kits. Co-immunoprecipitation and immunofluorescence staining were used to determine the relationship among pyruvate kinase M2 (PKM2), prolyl hydroxylase 3 (PHD3), and hypoxia-inducible factor-1α (HIF-1α). The expressions of PHD3, PKM2, HIF-1α, Bax, cleaved caspase-3, and Bcl-2 in SMMC-7721 cells were detected with Western blotting, and cell apoptosis was analyzed with annexin V-FITC/PI staining. The effects of RNA interference of PKM2 on PHD3 and HIF-1α expressions in SMMC-7721 cells were detected using Western blotting.
RESULTS:
The IC50 of shikonin against SMMC-7721 and L-02 cells was 8.041 μmol/L and 31.75 μmol/L, respectively. Treatment with shikonin significantly inhibited the protein expressions of PKM2, HIF-1α and PHD3 and nuclear translocation of PKM2 and HIF-1α in SMMC-7721 cells. Coimmunoprecipitation and immunofluorescence staining confirmed that shikonin inhibited the formation of PKM2/PHD3/HIF-1α complex and significantly reduced the contents of lactic acid and ATP in SMMC-7721 cells (P < 0.05). The expressions of PHD3 and HIF-1α decreased significantly after PKM2 knockdown (P < 0.05). Shikonin treatment significantly increased the apoptosis rate, enhanced the expressions of Bax and cleaved caspase-3, and decreased Bcl-2 expression in SMMC-7721 cells (P < 0.05).
CONCLUSIONS
Shikonin induces apoptosis of SMMC-7721 cells possibly by inhibiting aerobic glycolysis through the PKM2/PHD3/HIF-1α signaling pathway to cause energy supply dysfunction in the cells.
Humans
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Prolyl Hydroxylases
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Carcinoma, Hepatocellular
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Caspase 3
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bcl-2-Associated X Protein
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Liver Neoplasms
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Signal Transduction
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Apoptosis
;
Adenosine Triphosphate
6.Epidemiological characteristics and Spatial-temporal clustering of hand, foot and mouth disease in Shanxi province, 2009-2020.
Hao REN ; Yuan LIU ; Xu Chun WANG ; Mei Chen LI ; Di Chen QUAN ; Hua Xiang RAO ; Tian E LUO ; Jin Fang ZHAO ; Guo Hua LI ; Lixia QIU
Chinese Journal of Epidemiology 2022;43(11):1753-1760
Objective: To analyze the epidemiology and spatial-temporal distribution characteristics of hand, foot and mouth disease (HFMD) in Shanxi province. Methods: The data of HFMD in Shanxi province from 2009 to 2020 were collected from notifiable disease management information system of Chinese information system for disease control and prevention and analyzed by descriptive epidemiology, Joinpoint regression, spatial autocorrelation analysis and spatio- temporal scanning analysis. Results: A total of 293 477 HFMD cases were reported in Shanxi province from 2009 to 2020, with an average annual incidence of 67.64/100 000 (293 477/433 867 454), severe disease rate of 5.36/100 000 (2 326/433 867 454), severe disease ratio of 0.79%(2 326/293 477), mortality of 0.015/100 000 (66/433 867 454), and fatality rate of 22.49/100 000 (66/293 477). The reported incidence rate, severe disease rate, mortality rate and fatality rate of HFMD showed decreasing trends. The main high-risk groups were scattered children and kindergarten children aged 0-5. The incidence of HFMD had obvious seasonal variation, with two peaks every year: the main peak was during June-July, the secondary peak was during September-October and the peak period is from April to November. A total of 13 942 laboratory cases were confirmed, with a diagnosis rate of 4.75% (13 942/293 477), including 4 438 (35.11%, 4 438/293 477) Enterovirus A71 (EV-A71) positive cases, 4 609 (33.06%, 4 609/293 477) Coxsackievirus A16 (CV-A16) positive cases, and 4 895 (31.83%, 4 895/293 477) other enterovirus positive cases. There was a spatial positive correlation (Moran's I ranged from 0.12 to 0.58, all P<0.05) and the spatial clustering was obvious. High-risk regions were mainly distributed in Taiyuan in central Shanxi province, Linfen and Yuncheng in southern Shanxi province, and Changzhi in southeastern Shanxi province. Spatial-temporal scanning analysis revealed 1 the most likely cluster and 8 secondary likely clusters, of which the most likely cluster (RR=2.65, LLR=22 387.42, P<0.001) located in Taiyuan and Jinzhong city, Shanxi province, including 12 counties (districts), and accumulated from April 1, 2009 to November 30, 2018. Conclusions: There was obvious spatial-temporal clustering of HFMD in Shanxi province, and the epidemic situation was in decline. The key areas were the districts in urban areas and the counties adjacent to it. Meanwhile, the monitoring and classification of other enterovirus types of HFMD should be strengthened.
Child
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Humans
;
Hand, Foot and Mouth Disease/epidemiology*
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Spatial Analysis
;
Enterovirus Infections
;
Spatio-Temporal Analysis
;
Cluster Analysis
7.Comparative study between 3D guide plate assisted and free-hand insertion of anterior cervical transpedicular screw.
Jie LI ; Liu-Jun ZHAO ; Min-Zhe ZHENG ; Kai-Feng GAN ; Yi-Lei CHEN ; Zong-Xian FENG ; Ling-Xiao PAN ; Jun-Xiang XU ; Teng-di FAN ; Jing-Yang CHEN ; Feng-Dong ZHAO
China Journal of Orthopaedics and Traumatology 2021;34(1):45-50
OBJECTIVE:
To compare accuracy of anterior cervical pedicle screws between assist of rapid prototyping 3D guide plate and free-hand insertion, and evaluate the safety of two methods.
METHODS:
Eight adult cervical cadaver specimens after formaldehyde immersion, including 4 males and 4 females, aged 32 to 65(40.3±5.6) years old. After X-ray examination to exclude bone damage and deformity, 4 of them (3D guide plate group) randomly selected were for CT scan to obtain DICOM format data, and the data was imported into Mimics software for model, designed the ideal entry point and nail path for anterior cervicaltranspedicular screw (ATPS). After obtaining the personalized guide plate of the nail channel, it was exported as STL data, and the individual guide plate was printed by rapid prototyping and 3D printing technology. In turn, with the assistance of 3D guide plates, one-to-one personalized ATPS screws were placed on the four lower cervical cadaver specimens. Another 4 (free-hand group) lower cervical cadaver specimens were implanted with ATPS screws using free-hand technique. All specimens were performed CT thin-layer scanning and three-dimensional reconstruction after operation. The Tomasino method was used to evaluate the safety of the screws on the CT cross-sectional and sagittal images, to determine whether there was a cortical puncture of the lower and inner edges of the pedicle. According to the CT rating results, gradeⅠandⅡwere safe, and grade Ⅲ- Ⅴ were dangerous.And the accuracy of screws was recorded and analyzed between two groups.
RESULTS:
Two screws were inserted in each segment from C
CONCLUSION
The 3D printing rapid prototyping guide plate assisted insertion of the anterior cervical pedicle screw can significantly improve the accuracy and safety, and provide a theoretical basis for further clinical application.
Adult
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Aged
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Bone Plates
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Cervical Vertebrae/surgery*
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Cross-Sectional Studies
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Female
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Humans
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Male
;
Middle Aged
;
Pedicle Screws
;
Printing, Three-Dimensional
8.Application of liver three-dimensional visualized reconstruction technique in hepatectomy for children with complicated hepatoblastoma
Di ZHAO ; Jindong YE ; Huali LI ; Kui JIN ; Xiang LIU ; Xiaoran LI ; Liuxin DUAN ; Jungui LIU ; Wei LYU ; Weihong DUAN ; Quanda LIU
Journal of Clinical Hepatology 2021;37(9):2130-2135
Objective To investigate the application of liver three-dimensional (3D) visualized reconstruction technique in hepatectomy for children with complicated hepatoblastoma. Methods A retrospective analysis was performed for the clinical data of 30 children with hepatoblastoma who underwent hepatectomy for radical resection in PLA Rocket Force Characteristic Medical Center from January 2018 to October 2020, and according to whether liver 3D visualization with IQQA-Liver system was performed before surgery, the children were divided into 3D reconstruction group with 15 children and control group with 15 children. The two groups were compared in terms of perioperative parameters, short-term prognosis, and follow-up conditions. The independent samples t -test was used for comparison of normally distributed continuous data between two groups, and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups; the Fisher's exact test was used for comparison of categorical data between two groups. Results Compared with the control group, the 3D reconstruction group had a significantly higher mean age (55.7±10.2 years vs 28.2±2.7 years, P < 0.05) and a significantly higher number of patients with POSTTEXT stage III/VI hepatoblastoma (12 vs 5, P < 0.05) or involvement of the hepatic vein or the inferior vena cava (11 vs 3, P < 0.05). All children completed the surgery successfully, and there were no significant differences between the two groups in blood loss, time of operation, number of times and duration of hepatic portal occlusion, and number of children receiving segmental hepatectomy or partial hepatectomy (all P > 0.05). The median follow-up after surgery was 9.5 months. In the 3D reconstruction group, 2 children experienced recurrence and were diagnosed at 10 and 12 months, respectively, after surgery, and they were treated with chemotherapy at the moment; in the control group, 4 children experienced recurrence, which was higher than that in the 3D reconstruction group ( P =0.651), and among these 4 children, 2 had recurrence at 7 months after surgery, received liver transplantation, and survived up to now, and the other 2 children died shortly after recurrence. Conclusion 3D visualized reconstruction technique helps to perform hepatectomy for children with complicated hepatoblastoma more safely and accurately, especially extended hepatectomy for patients with stage POST TEXT III/IV hepatoblastoma, thereby avoiding liver transplantation.
9.Prediction of Disintegration Time of Traditional Chinese Medicine Tablets Based on Generalized Regression Neural Network
Xiang-yin YE ; Hai-ning ZHAO ; Ya-jing WANG ; Di GAO ; Yan-wen WANG ; Li-na SHANG ; Yi ZHANG ; Meng-nan ZHOU
Chinese Journal of Experimental Traditional Medical Formulae 2021;27(7):121-126
Objective:This paper constructs a generalized regression neural network (GRNN) model to predict the disintegration time of traditional Chinese medicine (TCM) tablets. Method:Taking Astragali Radix as a model drug, the mixed Astragali Radix powders with different powder properties were prepared by mixing Astragali Radix extract powders with microcrystalline cellulose and lactose, which were made to Astragali Radix tablets by direct compression method. The powder properties of mixed Astragali Radix powders and the disintegration time of Astragali Radix tablets were determined, respectively. The correlation between the original data was eliminated by principal component analysis (PCA). The principal component factors were used as the input layer of the GRNN model, and the disintegration time was used as the output layer for network training. Finally, the verification group data was used to predict the disintegration time, and the network prediction accuracy was calculated by comparing with the actual value. Result:Three principal component factors were obtained through PCA by analyzing the original nine variables that were correlated with each other (Hausner ratio, true density, tap density, compression degree, angle of repose, bulk density, porosity, water content and total dissolved solids), which reduced the complexity of the network. The prediction value of the disintegration time based on this prediction method was in good agreement with the actual value, the error of disintegration time was 0.01-1.34 min and the average relative error was 3.16%. Conclusion:Based on the GRNN mathematical model, the physical properties of Astragali Radix extract powders can be used to accurately predict the disintegration time of Astragali Radix tablets, which provides a reference for studying the disintegration time of TCM tablets.
10.The molecular mechanism of fibroblast growth factor 21-inhibited leptin expression in adipocytes.
Di CHEN ; Yan-Yan ZHAO ; Xiang-Yan LIANG ; Li-Jun ZHANG ; Lan-Lan WEI ; Rong XIE ; Xiao-Chun ZHANG ; Xing-Li SU ; Yu-Feng ZHAO
Acta Physiologica Sinica 2020;72(2):175-180
The present study was aimed to clarify the signaling molecular mechanism by which fibroblast growth factor 21 (FGF21) regulates leptin gene expression in adipocytes. Differentiated 3T3-F442A adipocytes were used as study object. The mRNA expression level of leptin was detected by fluorescence quantitative RT-PCR. The phosphorylation levels of proteins of signal transduction pathways were detected by Western blot. The results showed that FGF21 significantly down-regulated the mRNA expression level of leptin in adipocytes, and FGF21 receptor inhibitor BGJ-398 could completely block this effect. FGF21 up-regulated the phosphorylation levels of ERK1/2 and AMPK in adipocytes. Either ERK1/2 inhibitor SCH772984 or AMPK inhibitor Compound C could partially block the inhibitory effect of FGF21, and the combined application of these two inhibitors completely blocked the effect of FGF21. Neither PI3K inhibitor LY294002 nor Akt inhibitor AZD5363 affected the inhibitory effect of FGF21 on leptin gene expression. These results suggest that FGF21 may inhibit leptin gene expression by activating ERK1/2 and AMPK signaling pathways in adipocytes.
3T3 Cells
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Adenylate Kinase
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Adipocytes
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metabolism
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Animals
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Down-Regulation
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Fibroblast Growth Factors
;
metabolism
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Leptin
;
metabolism
;
MAP Kinase Signaling System
;
Mice
;
Phosphorylation
;
Signal Transduction

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