The perineural invasion (PNI) of malignant tumors is a form of tumor progression in which cancer cells encroach along nerves. PNI hinders curative resection. Residual tumor cells in or around nerves can bring about local recurrence, infiltration and metastasis. This behavior is usually associated with a poor clinical prognosis. Therefore, it is necessary to investigate novel ligand-receptor crosstalk between nerves and tumor cells that promote the process of PNI. Chemokines are regarded as one of pivotal factors involved in the process of PNI. The present review collates information provided by previous studies with regard to the role of chemokines in PNI. The study presents a definition of PNI in cancer, generalizes the biological characteristics and the expression of chemokines and their receptors in cancer types associated with PNI, and discusses the underlying molecular mechanisms of chemokines, the reciprocal interactions between chemokines and other factors in PNI, and the interconnectivity of the microenvironment and chemokines. The aim of the review is to thoroughly illustrate the molecular cues of chemokines in cancer with PNI and to identify novel antitumor targets.
In order to culture more and more and excellent anesthetic specialists,we summarized the teaching methods used in our clinical teaching,including entroll education,on duty rule perform,clinical standard operation teaching,anesthetic-plan paper writting,cases discussing,topic lecture and dean duty of the specianist class,so as to improve the ability of clinical anesthetic teaching.
Key words:
Anesthetic speciality; Practition; Clinical practice ability; Culture
Micromotion and fretting damages at the dental implant/bone interface are neglected for the limitation of check methods, but it is particularly important for the initial success of osseointegration and the life time of dental implant. This review article describes the scientific documentation of micromotion and fretting damages on the dental implant/bone interface. The fretting amplitude is less than 30 µm in vitro and the damage in the interface is acceptable. While in vivo, the micromotion's effect is the combination of damage in tissue level and the real biological reaction. Tiny movements at the contact area between dental implants and the underlying bone surface can cause wear and tear that threatens the long-term integrity of dental prostheses. This problem of so-called 'fretting damage' was long ignored by dentists and dental surgeons. Now, a review by Hai-Yang Yu and colleagues at Sichuan University in Chengdu, China, shows that the micrometer-scale movements at the dental implant–bone interface can actually be subdivided into two types: tangential fretting, which is caused by the direct contact stress of mastication, and radial fretting, which arises from the grinding-like pressure between the two surfaces when they remain in contact. The combination of these stresses leads to small cracks that are a big problem in the replacement of missing teeth by implant-supported prostheses.
The aim of this study was to evaluate the effects of various acidic solutions on the surface mechanical properties of commercial resin composites with different microstructures (Filtek Z350 XT, TPH 3 , Durafill, and Superlux). Specimens were immersed in orange juice, cola, and distilled water for 5 days and the nanohardness, elastic modulus, and wear behavior of the samples were determined via the nanoindentation test and a reciprocating nanoscratch test. The nanoscratch morphology was observed using scanning electron microscopy (SEM) and the wear depth was recorded by scanning probe microscopy (SPM). The results indicate that the nanofilled resin composites had the greatest hardest and highest elastic modulus, whereas the microfilled composites exhibited the lowest nanohardness and elastic modulus values. SEM observations showed that all resin composites underwent erosion and surface degradation after immersion in acidic solutions. Furthermore, the wear resistance was influenced by the composition of the acidic solution and was correlated with the nanohardness and elastic modulus. The dominant wear mechanism changed from plastic deformation to delamination after immersion in acidic solutions.
Podophyllotoxin (PTOX) is a biologically active compound derived from the podophyllum plant, and both it and its derivatives possess excellent antitumor activity. The PTOX derivatives etoposide (VP-16) and teniposide (VM-26) have been approved by the U.S. Food and Drug Administration (FDA) for cancer treatment, but are far from perfect. Hence, numerous PTOX derivatives have been developed to address the major limitations of PTOX, such as systemic toxicity, drug resistance, and low bioavailability. Regarding their anticancer mechanism, extensive studies have revealed that PTOX derivatives can induce cell cycle G2/M arrest and DNA/RNA breaks by targeting tubulin and topoisomerase II, respectively. However, few studies are dedicated to exploring the interactions between PTOX derivatives and downstream cancer-related signaling pathways, which is reasonably important for gaining insight into the role of PTOX. This review provides a comprehensive analysis of the role of PTOX derivatives in the biological behavior of tumors and potential molecular signaling pathways, aiming to help researchers design and develop better PTOX derivatives.
To investigate impact of ulinastatin (UTI) on sigma-1 receptor (σ1R) and binding immunoglobulin protein (BiP) after cerebral ischemia/reperfusion injury. The middle cerebral artery occlusion (MCAO) model was used to induce cerebral ischemia/reperfusion injury. Eighty male Sprague Dawley rats were randomly divided into 6 groups: control, MCAO, MCAO+50,000 U/kg UTI, MCAO+100,000 U/kg UTI, MCAO+200,000 U/kg UTI, MCAO+300,000 U/kg UTI. At 24 and 48 hours after MCAO, infarct volume, neurological dysfunction, and grip strength test were measured, and level of σ1R and BiP proteins was further detected using Western blot. Molecular docking assays were carried out to verify interaction between σ1R, BiP, and UTI. The serum concentration of BiP and the binding assay between σ1R, BiP, and UTI were determined using enzyme-linked immunosorbent assay. UTI increased the modified neurological severity score and upregulated σ1R and BiP expression in the cerebral cortex after MCAO. The grip strength of forelimbs increased significantly in the MCAO+200,000 U/kg UTI and MCAO+300,000 U/kg UTI groups compared with the MCAO group, while BiP serum levels remained unchanged. The molecular docking assay indicated putative binding between σ1R, BiP, and UTI. The binding assay also revealed that both σ1R and BiP could be combined with UTI. UTI displays a neuroprotective effect via upregulation of σ1R and BiP during ischemia/reperfusion injury, suggesting that UTI modulates σ1R and BiP and their interaction may provide a novel insight into potential therapeutic mechanisms for stroke.
During the outbreak of novel coronavirus pneumonia (NCP), dentists are at risk for more severe infection due to their professionalism. This article analyzed the route of infection during diagnosis and treatment of oral diseases. Following the related standards and guidelines of National Health Commission, the types, evaluation index and standards of medical and protective masks were summarized. It is expected to provide certain reference for the selection and use of masks of dental medical staff.