Fabrication and evaluation of porous coatings doped with bioactive elements on titanium surfaces.

OBJECTIVE: Although pure titanium (PT) and its alloys exhibit excellent mechanical properties, they lack biological activity as implants. The purpose of this study was to improve the biological activity of titanium implants through surface modification. MATERIALS AND METHODS: Titanium was processed into titanium discs, where the titanium discs served as anodes and stainless steel served as cathodes, and a copper- and cobalt-doped porous coating [pure titanium model (PTM)] was prepared on the surface of titanium via plasma electrolytic oxidation. The surface characteristics of the coating were evaluated using field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and profilometry. The corrosion resistance of PTM was evaluated with an electrochemical workstation. The biocompatibility and bioactivity of coated bone marrow mesenchymal stem cells (BMSCs) were evaluated through in vitro cell experiments. RESULTS: A copper- and cobalt-doped porous coating was successfully prepared on the surface of titanium, and the doping of copper and cobalt did not change the surface topography of the coating. The porous coating increased the surface roughness of titanium and improved its resistance to corrosion. In addition, the porous coating doped with copper and cobalt promoted the adhesion and spreading of BMSCs. CONCLUSIONS: A porous coating doped with copper and cobalt was prepared on the surface of titanium through plasma electrolytic oxidation. The coating not only improved the roughness and corrosion resistance of titanium but also exhibited good biological activity.

Clinical effect of open reduction and internal fixation with a steel plate through the triceps approach in the treatment of fractures of the middle and lower 1/3 of the humerus.

OBJECTIVE: The stability of fractures of the middle and lower 1/3 of the displaced humeral shaft is poor, and surgery is currently the main treatment. The posterolateral approach to the upper arm has many advantages but it is not widely used in clinical applications. The aim of the study was to investigate the clinical effect of open reduction and internal fixation with a steel plate through the triceps approach in the treatment of fractures of the middle and lower 1/3 of the humerus. PATIENTS AND METHODS: A retrospective analysis was performed on 26 patients with fractures of the middle and lower 1/3 of the humerus who were admitted to our hospital from January 2018 to December 2021. According to the AO ASIF classification, 12 patients had type A, 8 patients had type B, and 6 patients had type C fractures. The posterior transtriceps approach was used for open reduction and internal fixation with a steel plate to evaluate its clinical efficacy. RESULTS: All patients were followed completely, and the follow-up time was 6.0-18.0 months. Fracture nonunion occurred in 1 patient after the operation, and the other 25 patients healed well; 2 patients showed symptoms of radial nerve injury and numbness in the tiger's mouth area, which improved after 2 weeks. The average healing time of the fracture was 12.3 weeks. There were no infections or complications such as plate fractures. Elbow joint function according to Mayo scoring standards was as follows: 19 cases were excellent, 3 cases were good, 2 cases were fair, and 2 cases were poor. The excellent and good rate was 84.6%. CONCLUSIONS: Open reduction through the triceps approach and internal fixation with a steel plate for the treatment of the middle and lower 1/3 of the humerus can directly expose and protect the radial nerve and its branches and reduce radial nerve damage, and plate fixation on the tension side is biomechanical and worthy of clinical application.

Glove and instrument changing to prevent tumour seeding in cancer surgery: a survey of surgeons' beliefs and practices.

Background: Some surgeons change gloves and instruments after the extirpative phase of cancer surgery with the intent of reducing the risk of local and wound recurrence. Although this practice is conceptually appealing, the evidence that gloves or instruments act as vectors of cancer-cell seeding in the clinical setting is weak. To determine the potential effect of further investigation of this question, we surveyed the practices and beliefs of a broad spectrum of surgeons who operate on cancer patients. Methods: Using a modified Dillman approach, a survey was mailed to all 945 general surgeons listed in the College of Physicians and Surgeons of Ontario public registry. The survey consisted of multiple-choice and free-text response questions. Responses were tabulated and grouped into themes, including specific intraoperative events and surgeon training. Predictive variables were analyzed by chi-square test. Results: Of 459 surveys returned (adjusted response rate: 46%), 351 met the inclusion criteria for retention. Of those respondents, 52% reported that they change gloves during cancer resections with the intent of decreasing the risk of tumour seeding, and 40%, that they change instruments for that purpose. The proportion of respondents indicating that they take measures to protect the wound was 73% for laparoscopic cancer resections and 31% for open resections. Training and years in practice predicted some of the foregoing behaviours. The most commonly cited basis for adopting specific strategies to prevent tumour seeding was "gut feeling," followed by clinical training. Most respondents believe that it is possible or probable that surgical gloves or instruments harbour malignant cells, but that a cancer recurrence proceeding from that situation is unlikely. Conclusions: There is no consensus on how gloves and instruments should be handled in cancer operations. Further investigation is warranted.

A novel role for Plk4 in regulating cell spreading and motility.

Polo family kinase 4 (Plk4) is required for mitotic progression, and is haploinsufficient for tumor suppression and timely hepatocyte polarization in regenerating liver. At the same time, recent evidence suggests that Plk4 expression may have a role in clinical cancer progression, although the mechanisms are not clear. Here we identify a gene expression pattern predictive of reduced motility in Plk4(+/-) murine embryonic fibroblasts (MEFs) and validate this prediction with functional assays of cell spreading, migration and invasion. Increased Plk4 expression enhances cell spreading in Plk4(+/-) MEFs and migration in human embryonic kidney 293T cells, and increases invasion by DLD-1 colon cancer cells. Plk4 depletion impairs invasion of wild-type MEFs and suppresses invasion by MDA-MB231 breast cancer cells. Cytoskeletal reorganization and development of polarity are impaired in Plk4-deficient cells that have been stimulated to migrate. Endogenous Plk4 phosphorylated at the autophosphorylation site S305 localizes to the protrusions of motile cells, coincident with the RhoA GEF Ect2, GTP-bound RhoA and the RhoA effector mDia. Taken together, our findings reveal an unexpected activity of Plk4 that promotes cell migration and may underlie an association between increased Plk4 expression, cancer progression and death from metastasis in solid tumor patients.

[Experimental study on combining selective rhizotomy of different anterior and posterior sacral roots for restoration of bladder function after spinal cord injury].

OBJECTIVE: To investigate an alternative procedure for complete denervation of bladder in the supra-cone cord injury to restore the bladder function. METHODS: Sixteen dogs were included in this study after their spinal cords were transected above the cone. They were divided into 6 groups and performed the rhizotomy of L7 to S3 root in different combination respectively. The bladder and urethra pressure change by electrostimulation during operation and cystometrogram change after operation were tested. RESULTS: 1. Electrostimulation study: for bladder innervation, S2 was the most important and S1 was secondary. While for urethra innervation, S1 was more important than S2. When the anterior and posterior roots of S1 and S2 were intact with rhizotomy of posterior roots of L7 and S3, stimulated the common or posterior root of S1 and S2, the change of pressure in bladder and urethra was the same. When the anterior roots of S1 and S2 were resected with rhizotomy of posterior roots of L7 and S3, the pressure in bladder and urethra was significant decreased compared to stimulating the corresponding posterior roots. 2. Cystometrogram (CMG) study: in the complete deafferented group, resecting the posterior roots of L7 to S3, the bladder became flaccid. While resecting the posterior root of S2 and anterior root of S1 or, resecting the posterior root of S1 and anterior root of S2, combining with rhizotomy of posterior roots of L7 and S3, the CMG curve was similar to the complete deafferented group. In the S1 and S2 intact group, the bladder became spastic. CONCLUSION: Combining rhizotomy of anterior and posterior sacral root in different level has the same effects on bladder as complete deafferentation.

A new bicoumarin from Stellera chamaejasme L.

Thirteen compounds were isolated from roots of Stellera chamaejasme L. (Thymelaeaceae). They are 3-sitosterol (2), simplexin (3), pimelea factor P2 (4), daucosterol (5), (+)-3-hydroxy-1,5-diphenyl-1-pentanone (6), 4-ethoxy-benzoic acid (7), 2,4,6-Trimethoxy-benzoic acid (8), (+)-afzelechin (9), fumaric acid (10), N,N-dimethyl-L-aspartic acid (11), umbelliferone (12), daphniretin (13) and a novel bicoumarin named bicoumastechamin (1). Among the known compounds, 7, 8, 9, 10 and 11 were first isolated from this plant, and 6 was first isolated from the natural resources. Their structures have been elucidated on the basis of spectral data. In vitro bioassays showed that 4 inhibited cancer cell growth, 13 exhibited immunomodulatory activity, and 6 exhibited both immunomodulatory and anti-tumor activity.

[Studies on the alkaloids of Cephalotaxus. VII. Structures and semi-synthesis of two anticancer cephalotaxine esters].

Two new alkaloids, namely neoharringtonine (1) and anhydroharringtonine (2) with significant antileukemic activity were isolated from Cephalotaxus fortunei Hook f.. Their structures have been established by spectral analyses and semi-synthesis. Seven known alkaloids, deoxyharringtonine (3), isoharringtonine (4), isocephalotaxinone (5), acetylcephalotaxine (6), cephalotaxine (7), harringtonine (8) and homoharringtonine (9), were also isolated and identified.

[Studies on the alkaloids of Cephalotaxus. IX. Semi-synthesis of cephalotaxine esters and their anti-leukemic activity].

Harringtonine, homoharringtonine, deoxyharringtonine and isoharringtonine isolated from Cephalotaxus plant are the esters of cephalotaxine with significant inhibitory activity against P-388 leukemia. In this investigation seventeen new esters of cephalotaxine type alkaloids have been synthesized. Preliminary pharmacological examination showed that compounds 1, 2, 2 + 3, 6 and 8 showed similar antileukemic activity as homoharringtonine. Compounds 4, 5, 15 and 16 showed moderate inhibitory activity. Some structure activity correlations of these esters were discussed.

Studies on bioactive components from Chinese medicinal plants.

Several novel bioactive components isolated from Chinese medicinal plants will be presented. These include novel maytansinoid tumor inhibitors, some new ent-kaurane and rosane diterpenoids from Mallotus anomalus Meer et Chun (Euphorbiaceae), as well as novel insecticide, stemona alkaloids from Stemona parviflora C. H. Wright (Stemonaceae). Both are native plants of Hainan island, China. 2D NMR techniques such as mono and hetero-COSY, NOESY, COLOC as well as 1H-NMR line broadening effect were utilized for structure elucidation. The separation techniques, structure elucidations and bioassay results will be reported.

Recent advances in studies on Chinese medicinal herbs with physiological activity.

Medicinal plants with physiological activity studied in China during recent years are classified into three types: (1) drugs originating from traditional medicine and ancient prescriptions; (2) drugs originating from folk prescriptions or experienced prescriptions; (3) drugs originating from Chinese drugs with modified structures of the active principles and now in common use. The physiological activities are discussed in separate sections according to their therapeutic effects: nervous system; parasites; cardiovascular system; cancer; birth control; immuno-activity.