Cellular mechanics is a branch of tissue engineering and cellular engineering. As one of the important method, loading different mechanical stimuli to culturing cells in vitro so as to study the influence that the stress has on the cells is one of the important fields of cellular mechanics. This paper reviews the experimental methods for mechanically stimulating the cells in vitro, according to the different loading modalities, the methods can be categorized into micropipette aspiration, compression loading, substrate distention, fluid shear, etc. And it also points out their advantages and disadvantages.
Cell Culture Techniques ; Cells, Cultured ; Humans ; Stress, Mechanical ; Tissue Engineering

Iatrogenic gastrointestinal perforation is one of the severe adverse events of endoscopic therapeutic procedure. For acute iatrogenic perforation,management by endoscopic techniques is a simple and rapid modality to close the perforation with minimal invasiveness and avoiding the traditional surgical trauma. Endoclips,suture with special instruments,covered stents,degradable sheets combined with tissue adhesive,and combined endoscopic techniques such as snares combined with endoclips,are the major endoscopic therapeutic modalities for closure of iatrogenic gastrointestinal perforation. In this article,the current status and progress of endoscopic management for acute iatrogenic gastrointestinal perforation were reviewed.

A three-dimensional finite element model of the cell culture membrane was developed in the culture device under tension state made by us. The magnitude of tension and the displacement distribution in the membrane made of silicon rubber under different hydrostatic load were obtained by use of FEM analysis. A comparative study was made between the numerical and the experimental results. These results can serve as guides to the related cellular mechanical research.
Animals ; Biomechanical Phenomena ; Cell Culture Techniques ; Finite Element Analysis ; Imaging, Three-Dimensional ; Membranes, Artificial ; Rats ; Rats, Sprague-Dawley ; Silicone Elastomers

The plantar pressure and shear force measurement, the function and effect of joints, bones and ligaments of foot during running and walking, and the modeling and finite element analysis of human foot are three important aspects in biomechanical study of foot. They are also the basis of the study of rehabilitation. In this paper, studies on the three aspects are reviewed, and further promising developments are proposed.
Biomechanical Phenomena ; Diabetic Foot ; physiopathology ; Exercise ; physiology ; Finite Element Analysis ; Foot ; physiology ; Humans ; Pressure

Objective To study the different expressions of neurotensin (NT) at gene and protein level in orthotopic model of prostate cancer . Methods The animal models of androgen dependent prostate cancer(ADPC,castrated for 3 days) and androgen independent prostate cancer(AIPC) were established by planting tumor tissue or undergoing surgical castra-tion. Affymetrix microarray technology was carried out to compare the gene expressions of NT. The result was verified by qRT-PCR. HE staining was used to observe the change of pathology. ELSIA and immunohistochemistry technology were fi-nally performed to detect protein expression of prostate-specific antigen(PSA) and NT in three different groups of prostate cancer tumor tissues. Results The expression of NT was 5.10 times higher in AIPC group than that in ADPC group. The ex-pression of NT was 0.33 times lower in castrated 3-day group than that in ADPC group. Results of RT-PCR and qRT-PCR showed that the expression levels of NT gene were 1.41 and 7.27 times respectively higher in AIPC group than that in ADPC group,but the expression levels of NT gene were 0.78 and 0.46 times respectively lower in castrated 3-day group than that in ADPC group (P<0.05). HE results showed that nuclear atypia and tumor structure in three groups. Immunohistochemistry and ELISA results showed that the values of PSA and NT were (0.48±0.03) and (0.031±0.008)μg/L in ADPC group;(0.17± 0.03) and (0.021±0.004)μg/L in castrated 3-day group,and (0.87±0.02) and (0.042±0.010)μg/L in AIPC group. There were significantly lower expressions of NT and PSA in castrated 3-day group that those of ADPC group (P<0.01). Conclusion In the transition from ADPC to AIPC, the over-expression of NT suggested that NT may be associated with prostate cancer progression. NT may be used as a new therapeutic target and specific diagnostic method of AIPC.

Monolimb is a new type of lower-limb prostheses made of macromolecule polymer, in which the socket and prosthetic shank are integrative. Compared with traditional prosthesis, monolimb is more economical, good-looking and portable, so it indicates a possible direction in the future. Biomechanical research on trans-tibial monolimb is necessary and helpful just like traditional prosthesis. In this article, a 3D FE model based on real geometry shape of an endoskeletal trans-tibial monolimb is established. Keeping the same geometrical shape, three 3D FE models of transtibial monolimbs with different wall thickness are established. The influence of wall thickness on the stress distribution is analyzed under the load corresponding to the subphase of stance of Heel Off. The results indicate that stress within transtibial monolimb and pressure on the surface of soft tissue could be decreased with wall thickness of transtibial monolimb increased. This study will be helpful for the standard of wall thickness in designing transtibial monolimb.
Amputees ; rehabilitation ; Artificial Limbs ; Biomechanical Phenomena ; Humans ; Leg ; surgery ; Prosthesis Design ; Stress, Mechanical

Objective:To perform trans-peritoneal laparoscopic adrenalectomy via a single incision in treatment of adrenal tumors,and to discuss its clinical outcome and safety.Methods:Single incision trans-peritoneal laparoscopic adrenalectomy was used in treatment of three patients with adrenal tumors.The incision was made 3 cm below the costal margin of anterior axillary line; three Tocars were placed in the cut.The instruments used included single port access,CUSA,Hem-o-lok,etc..Results:The three operations were all successful,and there were no conversion to open procedure or a need for extra Ttrocars.The operating time periods were 75,116,and 135 min,with a mean of (108.7?30.7)min.The perioperative blood losses were 10,20,and 30 ml,with a mean of (20?10)ml.The gastric canal and ureteral catheter were withdrew one day after operation,and the drainage tube was withdrew 3 d after operation.The mean postoperative hospital stay was 4 d.Conclusion:Single incision trans-peritoneal laparoscopic adrenalectomy has the advantage of little trauma,less blood loss,satisfactory safety,and prompt postoperative recovery,but is difficult to manage.

OBJECTIVETo detect potential mutation of TCOF1 gene in a Chinese family affected with Treacher-Collins syndrome.

METHODSClinical data of the patient was collected. The analysis included history taking, clinical examination and genetic testing. All coding regions of the TCOF1 gene were subjected to PCR amplification and Sanger sequencing.

RESULTSA novel mutation c.2261ins G (p.E95X) of the TCOF1 gene was discovered in the patient. The same mutation was not found in his parents and 100 healthy controls.

CONCLUSIONThe c.2261insG (p.E95X) mutation of the TCOF1 gene probably underlies the disease in the patient. Genetic testing can facilitate diagnosis and genetic counseling for families affected with TCS.

BACKGROUND:Intervertebral disk degeneration is a pathological change caused by a series of complex molecular mechanisms that result in the aging and damage of intervertebral discs,ultimately leading to severe clinical symptoms.Traditional Chinese medicine has unique advantages in the treatment of intervertebral disk degeneration due to its low cost,non-addictive nature,multi-target effects,minimally toxic and side effects,and high patient acceptance. OBJECTIVE:To review the latest research results of traditional Chinese medicine monomer intervention-related signaling pathways in the treatment of intervertebral disk degeneration,describe and analyze the action mechanism of traditional Chinese medicine monomer on intervertebral disk degeneration,and provide a new approach and theoretical basis for future basic research and clinical treatment. METHODS:The first author searched for relevant literature from January 2018 to February 2023 in CNKI,PubMed,VIP,and WanFang using the search terms"intervertebral disc,signal pathway".The articles that did not meet the criteria were excluded after preliminary screening of the titles and abstracts.Finally,72 articles were selected for review and analysis. RESULTS AND CONCLUSION:Traditional Chinese medicine monomers can regulate multiple classical signaling pathways such as Wnt/β-catenin,PI3K/Akt,mTOR,NF-κB,and MAPK.They achieve this by regulating oxidative stress,adjusting the expression of pro/anti-apoptotic proteins in cells,stimulating cellular autophagy function,reducing stimulation of cell inflammatory factors,increasing the expression of extracellular matrix markers,reducing the production of matrix-degrading enzymes,maintaining the synthesis and stability of extracellular matrix,inducing differentiation of mesenchymal stem cells in the nucleus pulposus into nucleus pulposus cells,promoting endogenous repair and reconstruction,controlling apoptosis and aging of nucleus pulposus cells,and increasing the activity of nucleus pulposus cells.These actions improve the microenvironment within the intervertebral disc,maintain the normal physiological function of the intervertebral disc,and delay intervertebral disc degeneration.

BACKGROUND:At present,bone marrow mesenchymal stem cells are the main seed cells used in cell therapy for the treatment of intervertebral disc degeneration.However,the use of bone marrow mesenchymal stem cells as seed cells for the regeneration of fibrous rings is at risk of heterotopic ossification and teratoma at the repair site.Therefore,it is of great economic and social significance to find a new kind of seed cells for tissue engineering of annulus fibrosus for the treatment of intervertebral disc degeneration. OBJECTIVE:To isolate and purify rat annulus fibrosus-derived stem cells by adherent method combined with fibronectin differential adhesion screening method,and to observe its purification effect and biological characteristics. METHODS:Annulus fibrosus tissue was obtained from a SD rat intervertebral disc.Primary annulus fibrosus-derived stem cells were obtained by the mechanical-enzymatic digestion method.Annulus fibronectin differential adhesion method was used to purify annulus fibrosus-derived stem cells.Morphological changes and proliferation of cells were observed through a microscope.The expression levels of stem cell markers were detected by immunofluorescence technique and qPCR.The screened cells were subjected to multi-lineage cell differentiation and characteristic gene detection. RESULTS AND CONCLUSION:(1)The purified cells grew well,and most of them were angular and star-shaped multi-process cells,which had good proliferation ability.(2)Cells were positive for cell membrane surface antigens CD73,CD90 and CD105,while negative for CD45 and CD34.(3)After specific induction,cells could successfully differentiate into osteoblasts,chondroblasts and lipoblasts.(4)Collagen-I,Runx-2 after osteogenic induction,Collagen Ⅱ,Sox-9 after chondrogenic induction,and PPAR-γ and LPL after lipogenic induction were highly expressed in cells,and the difference was significant compared with that before induction(P<0.05).(5)These findings confirm that the adherent method combined with fibronectin differential adhesion method is effective enough to screen,isolate and purify rat annulus fibrosus-derived stem cells,and has good cell biological properties,good proliferation ability and multiple differentiation potential.