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1.
Journal of Medical Biomechanics ; (6): E402-E407, 2023.
Article in Chinese | WPRIM | ID: wpr-987965

ABSTRACT

The peripheral vestibular organs are sensors for linear acceleration (gravity and head tilt) and rotation,and turn them into nerve signals that travel to the central nervous system to regulate physiological functions, which play an important role in regulating body stability, ocular movement, autonomic nerve activity, arterial pressure, body temperature, as well as muscle and bone metabolism. The effect of gravity on these functions can be attributed to high plasticity of the vestibular system. In this review, changes in vestibular-related physiological functions induced by the hypergravity and microgravity were introduced, including arterial pressure,muscle and bone metabolism, feeding behavior and body temperature, with the aim to better understand the physiological function of vestibular in adaption to special gravity environment.

2.
Journal of Medical Biomechanics ; (6): E035-E042, 2020.
Article in Chinese | WPRIM | ID: wpr-804507

ABSTRACT

Objective To investigate the effect of microgravity on MC3T3-E1 osteoblast differentiation. Methods The differential miRNA and mRNA expression profiling of MC3T3-E1 cells during exposure to microgravity were established by RNA transcriptome sequencing technology (RNA-seq). The RNA sequencing results were validated using quantitative real-time polymerase chain reaction (q-PCR). Bioinformatic analyses were applied for further study of these differentially expressed miRNAs and mRNAs. Results Compared with control (CON) group, A total of 1 912 coding transcripts and 160 miRNAs were detected along with osteogenic differentiation in simulated microgravity (SMG) group. Bioinformatic analysis revealed 10 core regulatory genes including 7 mRNAs and 3 miRNAs. Based on the analysis and verification, one miRNA, miR-9_6666-5p, was identified, which might play an important role in osteogenic differentiation process under microgravity. Conclusions The process of osteoblast differentiation was repressed under microgravity which might be related to the changed expression profile of miRNA/mRNA. The research findings can contribute to the better understanding of the molecular mechanisms of mRNA and miRNAs in osteogenic differentiation and bone formation under the microgravity condition.

3.
Journal of Biomedical Engineering ; (6): 421-427, 2019.
Article in Chinese | WPRIM | ID: wpr-774189

ABSTRACT

In this study, we aim to investigat the effect of microgravity on osteoblast differentiation in osteoblast-like cells (MC3T3-E1). In addition, we explored the response mechanism of nuclear factor-kappa B (NF-κB) signaling pathway to "zero- " in MC3T3-E1 cells under the simulated microgravity conditions. MC3T3-E1 were cultured in conventional (CON) and simulated microgravity (SMG), respectively. Then, the expression of the related osteoblastic genes and the specific molecules in NF-κB signaling pathway were measured. The results showed that the mRNA and protein levels of alkaline phosphatase (ALP), osteocalcin (OCN) and type Ⅰ collagen (CoL-Ⅰ) were dramatically decreased under the simulated microgravity. Meanwhile, the NF-κB inhibitor α (IκB-α) protein level was decreased and the expressions of phosphorylation of IκB-α (p-IκB-α), p65 and phosphorylation of p65 (p-p65) were significantly up-regulated in SMG group. In addition, the IL-6 content in SMG group was increased compared to CON. These results indicated that simulated microgravity could activate the NF-κB pathway to regulate MC3T3-E1 cells differentiation.


Subject(s)
Animals , Mice , 3T3 Cells , Cell Differentiation , NF-kappa B , Physiology , Osteoblasts , Signal Transduction , Weightlessness Simulation
4.
Journal of Medical Biomechanics ; (6): E572-E576, 2018.
Article in Chinese | WPRIM | ID: wpr-803754

ABSTRACT

Bone remodeling can keep the biomechanical properties, which is of great significance to maintain bone strength. Normal skeletal development requires tight coordination of transcriptional networks, signaling pathways and biomechanical cues, and many of these pathways are dysregulated in pathological conditions affecting bone. lncRNA is a group of RNAs with broad biogenesis, which are longer than 200 nt and highly conserved in their secondary and tertiary structures. Studies show that many lncRNAs are involved in normal development or balance of the skeletal system, the regulation of osteoblast differentiation, and the pathogenesis of osteosarcoma. Dysregulation of lncRNA expression is closely related to many bone diseases and it is expected to be a biomarker for predicting bone diseases. In this review, the characteristics and mechanisms of lncRNA involved in bone remodeling and its possible role were summarized, and the likely utility of IncRNAs as biomarkers and therapeutic targets for diseases of the skeletal system was discussed, including osteoarthritis, osteoporosis, and cancers of the skeletal system, so as to provide references for the better understanding and study on lncRNA biological function in organisms.

5.
Journal of Medical Postgraduates ; (12): 706-709, 2014.
Article in Chinese | WPRIM | ID: wpr-453320

ABSTRACT

Objective This study was to analyze the causes of the complications of ultrasound -guided percutaneous renal bi-opsy in children . Methods We retrospectively analyzed the complications of ultrasound-guided percutaneous renal biopsy in 236 children along with the age, sex, sample length, times of puncture, and types of disease of the patients .We used the binary Logistic regression model to analyze the influences of various factors on the post -biopsy complications . Results After renal biopsy , 22 (9.3%) of the patients experienced various degrees of but no severe complications .The incidence of complications was significantly correlated with the sample length (P<0.05), but not with the age, sex, sample length, times of puncture, and types of disease of the patients. Conclusion Ultrasound-guided percutaneous renal biopsy is an effective diagnostic method for children , with a high suc-cess rate and a low incidence of complications .And the incidence of complications can be reduced by improving the skills of puncturing and accuracy of ultrasound positioning .

6.
Chinese Journal of Ultrasonography ; (12): 416-419, 2012.
Article in Chinese | WPRIM | ID: wpr-425739

ABSTRACT

Objective To investigate the correlation between elasticity obtained with acoustic radiation force impulse(ARFI) and blood perfusion obtained with contrast enhanced ultrasound(CEUS) in renal carcinoma.Methods Tweenty-four patients with renal carcinoma confirmed by operation and pathology underwent ARFI and CEUS sequentially,got preliminary information of elasticity,size and border with virtual touch tissue imaging (VTI),shear wave velocity (SWV) of tumor and renal cortex at least 2centimeters from the tumor margin were measured with virtual touch tissue quantification (VTQ),and then the imaging characteristics were analyzed with time intensity curve (TIC).The elasticity obtained with ARFI were compared with the blood perfusion obtained with CEUS.ResultsTotally 24 cases included 18 renal cell carcinomas,3 papillary renal cell carcinomas,2 chromophobe cell renal carcinomas and 1 rena1collecting duct carcinoma.In VTI,18 appeared darker,4 appeared brighter,and 2 had the same brightness as renal cortex.The SWV of tumor and renal cortex were (2.47±0.61)m/s,(2.10±0.94) m/s,respectively,19 were stiffer than renal cortex (79.2%),among which 18 appeared hyper-enhancement and 1 appeared hypo-enhancement;5 were softer than renal cortex (20.8%),among which 2 appeared hyper-enhancement and 3 appeared hypo-enhancement in CEUS.Tumors with different elasticity had different enhancement,stiff cases appeared hyper-enhancement,soft cases appeared hypo-enhancement (P < 0.05).Conclusions There is correlation between elasticity obtained with ARFI and blood perfusion obtained with CEUS in renal carcinoma

7.
Chinese Journal of Ultrasonography ; (12): 617-620, 2011.
Article in Chinese | WPRIM | ID: wpr-416500

ABSTRACT

Objective To investigate the value of contrast enhanced ultrasound(CEUS) with microbubbles targeted to vascular endothelial growth factor receptor type 2 (VEGFR2) for imaging tumor angiogenesis in murine tumor models.Methods Established human renal cell carcinomas(RCC) subcutaneous xenograft tumor model in nude mice,microbubbles targeted to VEGFR2(MBV) was prepared,control microbubbles(MBC) and MBV were injected respectively in each mouse,the intensity of each microbubble was compared,the expressions of VEGFR2 in tumors were tested by immunohistochemistry.Results CEUS imaging showed the intensity of MBV and MBC was (6.50±1.43)dB,(2.59±0.99)dB,respectively.There was significantly higher intensity when using MBV compared with MBC (P<0.01).The time to wash out was longer in MBV contrast group compared with MBC group.Immunohistochemistry showed VEGFR2 was highly expressed in novel vessel walls.Conclusions Contrast microbubbles targeted to VEGFR2 can specially enhance the images of RCC and has tremendous significance in the assessment of angiogenesis.

8.
Chinese Journal of Urology ; (12): 258-261, 2011.
Article in Chinese | WPRIM | ID: wpr-412697

ABSTRACT

Objective To discuss the imaging characteristics of chromophobic cell renal carcinoma (CCRC) and study the features on the contrast-enhanced ultrasound (CEUS). Methods The CEUS features of CCRC in 28 cases identified by pathology were reviewed. The blood supply and enhancement characteristic were observed and analyzed on time intensity curve parameters. Results The 28 cases of CCRC showed poor blood supply in contrast with the renal cortex. The CCRC presented with heterogeneity enhancement, part of the tumor took on a high wash-in and wash-out, and enhanced less intense than the surrounding renal cortex. The actinomorphous strong echo of the tumors might be revealed with CEUS in 15 cases (54%). The time intensity curve analysis demonstrated that the CCRCs' difference of peak intensity and area under the curve were lower than the renal cortex (P<0.05), but arrival time, time-to-peak and slope of ascending curve were higher than the renal medulla (P<0.05). Conclusion The actinomorphous enhancement and poor blood supply in the tumor of CEUS could provide diagnostic evidence for CRCC.

9.
Chinese Journal of Ultrasonography ; (12): 404-407, 2010.
Article in Chinese | WPRIM | ID: wpr-389659

ABSTRACT

Objective To analyze the misdiagnosis reasons in renal tumors with contrast-enhanced ultrasound (CEUS) and to improve cognition on CEUS. Methods Two-hundred and eighty-five cases were compared with pathology, the images in 22 cases misdiagnosed on CEUS were reviewed retrospectively and the reasons were analyzed. Results The diagnosis accuracy and misdiagnosis rate of CEUS were 92. 28 % (263/285) and 7. 72%(22/285), respectively. In these 22 cases, 9 cases misdiagnosed as renal cell carcinoma (RCC) were conformed by pathology as renal angiomyolipoma(RAMD), showed 5 cases "fast wash-in and fast wash-out", 4 cases "fast wash-in and slowly wash-out". Seven cases were conformed as RCC, in which 5 were misdiagnosed as RAML, showed 4 cases "fast wash-in and slowly wash-out", 1 cases "simultaneously wash-in and simultaneously wash-out", and 2 were misdiagnosed as renal cyst with no enhancement founded. Four cases misdiagnosed as hematoma were conformed as pyelo-carcinoma, with no enhancement founded in renal pelvis. The remaining 2 cases misdiagnosed as inflammatory pseudotumor were conformed as RCC, showed "fast wash-in and slowly wash-out". Conclusions With the high diagnosis accuracy,CEUS is an important method in diagnosis of renal tumors. Analyzing the misdiagnosed reasons may improve the cognition on CEUS and decrease the misdiagnosis.

10.
Chinese Journal of Ultrasonography ; (12): 693-696, 2010.
Article in Chinese | WPRIM | ID: wpr-387723

ABSTRACT

Objective To explore the value of contrast-enhanced ultrasound(CEUS) in the diagnosis of hematoma and active hemorrhage of renal trauma. Methods Totally 28 patients with renal trauma were examined by conventional ultrasound and CEUS,respectively,including 24 cases caused after renal biopsy,4closed trauma. The detectability of renal hematoma and active hemorrhage with these two methods were compared. All patients were identified by CT or follow-up studies with ultrasound. Results The detectability of renal hematoma with conventional ultrasound and CEUS were 67. 86% (19/28), 92. 86%(26/28), respectively. There was statistically different for detectability in the diagnosis ( P <0.05), and the extent of hematoma was more obvious with CEUS. CEUS diagnosed 7 of 26 were renal hematoma with active hemorrhage,which were difficult to be detected with conventional ultrasound. For renal hematoma,the features of CEUS were no enhancement found in every phase; for renal hematoma with active hemorrhage,the contrast agents overflowed from injured blood vessels and formed irregular remarkable enhanced regions. Conclusions CEUS is useful in diagnosing hematoma and identifying the extent and active hemorrhage of renal trauma,in addition,CEUS is valuable in detecting complications after renal biopsy.

11.
Chinese Journal of Ultrasonography ; (12): 783-786, 2010.
Article in Chinese | WPRIM | ID: wpr-387234

ABSTRACT

Objective To assess the differential diagnosis and characteristics of renal benign and malignant tumors with three-dimensional contrast-enhanced ultrasound (3D-CEUS). Methods Totally 68 patients with renal tumors were examined by conventional ultrasound and two-dimensional contrastenhanced ultrasound(2D-CEUS). 3D imaging was reconstructed from 2D imaging, the differential diagnosis of renal tumors with 3D-CEUS was analyzed by comparing with 2D-CEUS. All patients with renal tumors were proved by operational pathology. Results Eighteen patients with renal benign tumors mostly displayed equal or low enhancement, showed "slowly in and slowly out" with 2D-CEUS, while displayed regular peripheral and internal vessels with 3D-CEUS. Fifty patients with renal malignant tumors mostly displayed high enhancement, showed "rapidly in and rapidly out" with 2D-CEUS,displayed winding peripheral vessels and disordered internal vessels with 3D-CEUS. 3D-CEUS may display the vascular characteristics of tumors and showed superior imaging quality to 2D-CEUS ( P < 0.05). Conclusions 3D-CEUS can display the vascular characteristics of tumors and their spatial positions, it plays an important role in differential diagnosis between renal benign and malignant tumors.

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