Staphylococcus aureus giant protein Ebh is involved in tolerance to transient hyperosmotic pressure.

Staphylococcus aureus is well known to colonize on human skin where the physiological condition is characterized by hypervariable water activity, i.e., repeated dehydration or rehydration. To determine the facilitating factors for the colonization under hypervariable water activity, we studied the giant protein Ebh (extracellular matrix (ECM)-binding protein homologue). The ebh mutant RAM8 showed invaginated vacuoles along the septum, similar to that found in partial plasmolysis, and the cells burst under osmotic upshift. RAM8 was also relatively susceptible to abrupt hyperosmotic upshift, teicoplanin, and Triton X-100. By using the green fluorescent protein (GFP) as a reporter, Ebh was localized over the entire cell surface. This suggests that Ebh might contribute to structural homeostasis by forming a bridge between the cell-wall and cytoplasmic membrane to avoid plasmolysis under hyperosmotic condition.

The Intrinsic Relation between the Hydrogel Structure and In Vivo Performance of Hyaluronic Acid Dermal Fillers: A Comparative Study of Four Typical Dermal Fillers

BACKGROUND@#Hyaluronic acid dermal fillers are composed of cross-linked viscoelastic particles with high biocompatibility. The performance of the fillers is determined by the viscoelastic properties of particles and the connecting force between particles. However, the relationships among the properties of fillers, the interaction of the gels and the surrounding tissue are not clear enough.METHOD: Four kinds of typical dermal filler were selected in this research to reveal the interaction between the gels and cells. A series of analytical tools was applied to characterize the structure and physicochemical properties of the gel, as well as observing their interaction with the surrounding tissues in vivo and discussing their internal mechanism.RESULT: The large particles internal the gel and the high rheological properties endow the Restylane2 with excellent support. However, these large-size particles have a significant impact on the metabolism of the local tissue surrounding the gel. Juvéderm3 present gel integrity with the high cohesiveness and superior support. The rational matching of large and small particles provides the Juvéderm3 with supporting capacity and excellent biological performance. Ifresh is characterized by small-size particles, moderate cohesiveness, good integrity, lower viscoelasticity and the superior cellular activity located the surrounding tissues. Cryohyaluron has high cohesion and medium particle size and it is prominent in cell behaviors involving localized tissues. Specific macroporous structure in the gel may facilitate the nutrients delivering and removing the waste. @*CONCLUSION@#It’s necessary to make the filler both sufficient support and biocompatibility through the rational matching of particle sizes and rheological properties. Gels with macroporous structured particle showed an advantage in this area by providing a space inside the particle.

Robotic arm-assisted arthroplasty: The latest developments / 中华创伤杂志(英文版)

Joint arthroplasty is an effective method for treating end-stage joint lesions and damages. Robotic arm-assisted arthroplasty, a rapidly developing technology that combines navigation technology, minimally invasive technology, and precise control technology of the robotic arm, can achieve accurate preoperative planning, optimal selection of implants, minimally invasive surgery, precise osteotomy, and accurate placement of the artificial joint. It has the characteristics of high accuracy and stability, and thus is more and more widely used in the field of joint surgery. In this paper, we systematically reviewed the application and clinical efficacy of robotic arm-assisted technology in hip and knee arthroplasty to provide reference for its future promotion.

Effects of VEGF-Notch Signaling Pathway on Proliferation and Apoptosis of Bone Marrow MSC in Patients with Aplastic Anemia / 中国实验血液学杂志

OBJECTIVE@#To evaluate the regulation of VEGF-Notch signaling pathway on proliferation and apoptosis of mesenchymal stem cells (MSC) in the patients with aplastic anemia (AA).@*METHODS@#The bone marrow specimens of AA patients were collected for isolation and identification of BM MSC. Westen blot was used to detect the expression of VEGF-Notch signaling pathway-related proteins (VEGF, VEGFR, Notch 1, Jagged 1, Delta-like 1 and Hes1). The VEGF (100 ng/ml) and DAPT (γ-secretase inhibitor, 10 μmol/L) were respectively added into MSC culture system in oder to activate and inhibit the signaling transduction of VEGF-Notch in BM MSC. The proliferation, apoptosis and cell cycle of MSC in AA patients were detected by CCK8 assay and flow cyfometry. The adipogenic differentiation of BM MSC was detected by oil red O staining.@*RESULTS@#The VEGF-Notch signaling pathway was significantly inhibited in AA BM tissues and AA MSC (P＜0.05) detected by Western blot. The intervention of VEGF and DAPT significantly activated and inhibited VEGF-Notch signaling in AA MSC, respectively. CCK8 assay showed that VEGF intervention significantly promoted the proliferation of MSC in AA patients (P＜0.05). Flow cytometry showed that VEGF significantly inhibited apoptosis of MSCs by blocking S phase cells (P＜0.05).@*CONCLUSION@#The activation of VEGF-Notch can restore the proliferation function of MSC in AA patients.

BiomechanicaI finite eIement anaIysis on the bone interface of posterior mandibuIar area under different setting forces after incIined impIantation with angIed abutment / 中国组织工程研究

BACKGROUND: Single tooth loss at posterior mandibular area is difficult to complete regularly axial implantation under limited conditions. Concerning this problem, some scholars employ the skill of tilted implantation with abutment angulations to restore it. However, the security study of this design has been limited until now. OBJECTIVE: To provide theoretical evidence for tilted implantation in the posterior mandibular area, and to make a biomechanical analysis on bone-implant interface after titled implantation under the same dynamic force stress. METHODS: First, restoration models of implant crown at different tilting angles in posterior mandibular area were built and optimized using the software CBCT and DICOM. Then dynamic force stress was applied in chewing cycles of the crown model. Finally, the stress-strain analysis of bone-implant interface was made by utilizing the three-dimensional finite element software Ansys. RESULTS AND CONCLUSION: (1) When the dental implant in the axis implantation was tilted to the lingual side at 5° or 10°, the maximum stress and strain values at the bone interface were 53.8 MPa and 2 671, respectively, under three loading conditions: the force during the chewing cycle was given vertical to the implant, toward the lingual side from the buccal side at 45° with the long axis of the tooth, and toward the buccal side from the lingual side at 45° with the long axis of the tooth. (2) When the implant inclined to the lingual side at a 15° angle, the rear edge of the implant was close to the interface between the cortical and cancellous bone, and the stress and strain values were bigger than those at any other implantation angle. (3) When the implant inclined to the lingual side at a 20° angle, the rear edge of the implant was beyond the interface between the cortical and cancellous bone, and contacted with the cortical bone that provided a support for the rear part of the implant. The stress and strain values on the bone interface were both reduced. The stress was concentrated in the cortex around the neck of the implant, and reduced a lot in the cancellous bone. The maximum strain value appeared at the contact site between the bone interface and the implant neck or rear part. It is concluded that in posterior mandibular area, the dental implant can be implanted at a < 10° linguoclination angle.

Analysis of C5 palsy with C4/5 foraminotomy after posterior cervical decompression surgery / 天津医药

Objective To evaluate the effects of C4-5 partial foraminotomy on reducing the occurrence of C5 palsy after posterior cervical decompression surgery. Methods A total of 127 patients (male 62, female 65) underwent the cervical decompression surgery with lateral cervical mass screw insertion between January 2011 and December 2015 were retrospectively analyzed. In these patients sixty-one cases (Group A) underwent the posterior laminectomy with lateral cervical mass screw insertion, while 66 cases (Group B) received posterior laminectomy with lateral cervical mass screw insertion, combined with partial C4/5 foraminotomy at C4-5 level. The clinical data, radiographic parameters and the occurrence of C5 palsy were assessed in two groups of patients. Results There was no significant difference in JOA recovery rate and change of cervical curvature index between preoperation and postoperation in each group (P>0.05). Postoperative C5 palsy occurred in 11 cases (18.03%) in group A and 3 cases (4.05%) in group B. The difference in the incidence of C5 palsy was significant between the two groups (P=0.022). Conclusion The cervical decompression surgery can improve the function of the spinal cord effectively. C4-5 partial foraminotomy after cervical decompression surgery is effective for preventing C5 palsy.