The research of calcium phosphate cement (CPC) has been developing for more than 20 years. In this review, we present a brief introduction to recent advances in researches on apatite CPC, brushite CPC, composite CPC materials; on factors affecting CPC capability and application; and on new application of CPC. The view that emphasizes the significance of studies on CPC with quicker degradation and osteoblast activity is put forward, particularly.
Absorbable Implants ; Bone Cements ; chemistry ; therapeutic use ; Bone Substitutes ; chemistry ; therapeutic use ; Calcium Phosphates ; chemistry ; therapeutic use ; Humans

OBJECTIVETo evaluate the effects of repairing rabbit radial defects with polyester/tricalcium phosphate scaffolds prepared by rapid prototyping technology loaded with bovine bone morphogenetic protein (bBMP), and find new carriers for growth factors.

METHODSPolyester/tricalcium phosphate scaffolds prepared by rapid prototyping technology loaded with and without bovine BMP were used to repair the 15 mm radial defect in rabbit. Then the results of radiography, histology, scaffolds degrade rates and bone mineral density (BMD) were appraised to examine the effects at the 12th week.

RESULTSAt the 12th week postoperatively, all defects treated with bBMP were radiographically repaired. No radius implanted polyester/tricalcium phosphate scaffolds without bBMP showed radiographic and histological union. At experimental groups, longitudinal alignment of lamellar structure was observed histologically at the 12th week, indicating that remodeling of regenerated bone was complete in different degree. Of the three experimental groups, the bony regeneration and remodeling of callus in poly lactide-co-glycolide/tricalcium phosphate (PLGA/TCP) group was the best. The BMD values were beyond 70% of normal value at the 12th week while the PLGA/TCP scaffolds group was the highest, and no abnormalities were observed in the surrounding soft tissue in all groups.

CONCLUSIONSPolyester/tricalcium phosphate scaffolds prepared by rapid prototyping technology loaded with bovine BMP can repair a 15 mm radial defect of rabbit. As for the results, the PLGA/TCP scaffold is ideal and better than poly L-lactide-co-D, L-lactide (PDLLA/TCP) scaffold, but the ploy L-lactic acid (PLLA/TCP) is not so good for its low degradation rates.

Animals ; Bone Density ; Bone Morphogenetic Proteins ; Bone Regeneration ; Bone Substitutes ; therapeutic use ; Calcium Phosphates ; therapeutic use ; Polyesters ; therapeutic use ; Rabbits ; Radiography ; Radius ; diagnostic imaging ; pathology ; surgery

OBJECTIVE: To prepare an injectable hydrogel/staple fiber composite loaded with combretastain A-4 disodium phosphate (CA4P) and doxorubicin (DOX) and evaluate its antitumor efficacy via intratumoral injection. METHODS: DOX-loaded PELA staple fibers (F_DOX) were prepared using electro-spinning and cryo-cutting, and the drug distribution on the surface of the fibers was observed using a fluorescence microscope, and the encapsulation efficiency and loading capacity of F_DOX were determined with a fluorospectro photometer. The fibers were then dispersed in CA4P-loaded PLGA-PEG-PLGA tri-block polymer solution at room temperature to obtain the hydrogel/staple fiber composite (G_CA4P/F_DOX). The thermo-sensitivity of this composite was determined by a test tube inverting method. An ultraviolet spectrophotometer and a fluorospectrophotometer were used to detect the release profile of CA4P and DOX, respectively. We observed in vivo gel formation of the composite after subcutaneous injection in mice. The in vitro cytotoxicity of G_CA4P/F_DOX composite in MCF-7 and 4T1 cells was assessed using cell Counting Kit-8 (CCK-8) reagent. In a mouse model bearing breast tumor 4T1 cell xenograft, we evaluated the antitumor efficacy of the composite by monitoring tumor growth within 30 days after intratumoral injection of the composite. HE staining, immunohistochemistry for Ki67 and immunofluorescence (TUNEL) assay were used for pathological examination of the tumor tissues 21 days after the treatments. RESULTS: The average length of F_DOX was 4.0±1.3 μm, and its drug loading capacity was (2.69±0.35)% with an encapsulation efficiency of (89.70±0.12)%. DOX was well distributed on the surface of the fibers. When the temperature increased to 37 ℃, the composite rapidly solidified to form a gel in vitro. Drug release behavior test showed that CA4P was completely released from the composite in 5 days and 87% of DOX was released in 30 days. After subcutaneous injection, the composite solidified rapidly without degradation at 24 h after injection. After incubation with G_CA4P/F_DOX for 72 h, only 30.6% of MCF-7 cells and 28.9% of 4T1 cells were viable. In the tumor-bearing mice, the tumor volume was 771.9±76.9 mm³ in G_CA4P/F_DOX treatment group at 30 days. Pathological examination revealed obvious necrosis of the tumor tissues and tumor cell apoptosis induced by intratumoral injection of G_4A4P/F_DOX. CONCLUSION As an efficient dual drug delivery system, this hydrogel/staple fiber composite provides a new strategy for local combined chemotherapy of solid tumors.
Animals ; Breast Neoplasms/drug therapy* ; Cell Line, Tumor ; Delayed-Action Preparations/therapeutic use* ; Doxorubicin/therapeutic use* ; Female ; Heterografts ; Humans ; Hydrogels/therapeutic use* ; Mice ; Mice, Inbred BALB C ; Phosphates

This study aimed to evaluate the cost-effectiveness of Chaiyin Granules compared with Oseltamivir Phosphate Capsules in the treatment of influenza(exogenous wind-heat syndrome). Based on a randomized, double-blind, positive drug parallel control clinical trial, this study evaluated the pharmacoeconomics of Chaiyin Granules with cost-effectiveness analysis method. A total of 116 patients with influenza from eight hospitals(grade Ⅱ level A above) in 6 cities were selected in this study, including 78 cases in the experimental group with Chaiyin Granules and Oseltamivir Phosphate Capsules placebo, and 38 cases in the control group with Oseltamivir Phosphate Capsules and Chaiyin Granules placebo. The total cost of this study included direct medical cost, direct non-medical cost, and indirect cost. The remission time of clinical symptoms, cure time/cure rate, antipyretic onset time/complete antipyretic time, viral nucleic acid negative rate, and traditional Chinese medicine(TCM) syndrome curative effect were selected as the effect indicators for cost-effectiveness analysis. Four-quadrant diagram was used to estimate the incremental cost-effectiveness ratio. The results showed that Chaiyin Granules were not inferior to Oseltamivir Phosphate Capsules in the remission time of clinical symptoms of influenza(3.1 d vs 2.9 d, P=0.360, non-inferiority margin was 0.5 d). Compared with Oseltamivir Phosphate Capsules, Chaiyin Granules would delay the remission time of clinic symptoms of influenza for 1 d, but could save 213.9 yuan. 1 d delay in cure time could save 149.3 yuan; 1% reduction in the cure rate could save 8.2 yuan; 1 d delay in antipyretic onset time could save 295.4 yuan; 1 d delay in complete antipyretic time could save 114.3 yuan; 1% reduction in the 5-day cure rate of TCM syndrome could save 19.2 yuan. Different from other indicators, there was no statistically significant difference between two groups in the effect of negative conversion rate of viral nucleic acid, but the cost was lower and the effect was superior, and the pharmacoeconomics was not different from that of Oseltamivir Phosphate Capsules in the field of influenza treatment.
Humans ; Antipyretics/therapeutic use* ; Antiviral Agents/therapeutic use* ; Cost-Effectiveness Analysis ; Influenza, Human/drug therapy* ; Nucleic Acids/therapeutic use* ; Oseltamivir/therapeutic use* ; Phosphates/therapeutic use* ; Treatment Outcome ; Double-Blind Method

PURPOSETo develop a novel injectable strontium-containing calcium phosphate cement with collagen.

METHODSA novel calcium phosphate bone cement (CPC) was prepared with the addition of strontium element, collagenl, and modified starch; the injectability, solidification time, microstructure, phase composition, compressive strength, anti-collapsibility and histological properties of material were evaluated.

RESULTSThe results showed that the material could be injected with an excellent performance; the modified starch significantly improved the anti-washout property of cement; with the liquid to solid ratio of 0.3, the largest compressive strength of cement was obtained (48.0 MPa ± 2.3 MPa); histological examination of repair tissue showed that the bone was repaired after 16 weeks; the degradation of cement was consistent with the new bone growth.

CONCLUSIONA novel injectable collagen-strontium-containing CPC with excellent compressive strength and suitable setting time was prepared, with addition of modified starch. The CPC showed a good anti-washout property and the degradation time of the cement met with the new bone growing. This material is supposed to be used in orthopedic and maxillofacial surgery for bone defects.

Animals ; Bone Cements ; chemistry ; therapeutic use ; Calcium Phosphates ; chemistry ; Collagen ; chemistry ; Compressive Strength ; Histocompatibility Testing ; Injections ; Rabbits ; Strontium ; chemistry

BACKGROUNDA new treatment strategy is to target specific areas of the skeletal system that are prone to clinically significant osteoporotic fractures. We term this strategy as the "local treatment of osteoporosis". The study was performed to investigate the effect of alendronate-loaded calcium phosphate cement (CPC) as a novel drug delivery system for local treatment of osteoorosis.

METHODSAn in vitro study was performed using CPC fabricated with different concentrations of alendronate (ALE, 0, 2, 5, 10 weight percent (wt%)). The microstructure, setting time, infrared spectrum, biomechanics, drug release, and biocompatibility of the composite were measured in order to detect changes when mixing CPC with ALE. An in vivo study was also performed using 30 Sprague-Dawley rats randomly divided into six groups: normal, Sham (ovariectomized (OVX) + Sham), CPC with 2% ALE, 5%ALE, and 10% ALE groups. At 4 months after the implantation of the composite, animals were sacrificed and the caudal vertebrae (levels 4-7) were harvested for micro-CT examination and biomechanical testing.

RESULTSThe setting time and strength of CPC was significantly faster and greater than the other groups. The ALE release was sustained over 21 days, and the composite showed good biocompatibility. In micro-CT analysis, compared with the Sham group, there was a significant increase with regard to volumetric bone mineral density (BMD) and trabecular number (Tb.N) in the treated groups (P < 0.05). Trabecular spacing (Tb.Sp) showed a significant increase in the Sham group compared to other groups (P < 0.01). However, trabecular thickness (Tb.Th) showed no significant difference among the groups. In biomechanical testing, the maximum compression strength and stiffness of trabecular bone in the Sham group were lower than those in the experimental groups.

CONCLUSIONSThe ALE-loaded CPC displayed satisfactory properties in vitro, which can reverse the OVX rat vertebral trabecular bone microarchitecture and biomechanical properties in vivo.

Alendronate ; therapeutic use ; Animals ; Bone Cements ; chemistry ; therapeutic use ; Bone Density ; drug effects ; Calcium Phosphates ; chemistry ; Female ; Osteoporosis ; drug therapy ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the treatment effect of mandibular osteoradionecrosis (ORN) by autologous bone marrow mesenchymal stem cells (BMMSC) in miniature pigs.

METHODSSix miniature pigs with mandibular ORN (25 Gy) were used. BMMSC were separated and cultured in vitro and then implanted on to the premolded hydroxyapatite-tricalcium phosphate (HA-TCP). The BMMSC-HA-TCP complexes were implanted into the defective area of mandibular ORN in 4 animals. Implantation of only HA-TCP in 2 animals served as control. Gross observation, spiral CT, coronary CT and histopathologic examination were carried out.

RESULTSFistula disappeared in animals with BMMSC-HA-TCP complexes 3 months after implantation, while fistula was found in controls. Spiral CT analysis showed that cortical bone repair were found 4 months after BMMSC-HA-TCP complexes implantation, while bone damage (cortical and cancellous bone fracture) increased in controls. Histopathologic examination revealed that 4 months later after BMMSC-HA-TCP complexes implantation, new bone formation and bone cells could be observed, but there was a large number of fibrous tissue and no new bone in controls.

CONCLUSIONSTransplantation of autologous BMMSC with HA-TCP may have therapeutic effect in the treatment of mandibular ORN.

Animals ; Bone Marrow Cells ; Calcium Phosphates ; therapeutic use ; Durapatite ; therapeutic use ; Mandibular Diseases ; therapy ; Mesenchymal Stem Cell Transplantation ; Osteoradionecrosis ; therapy ; Swine ; Swine, Miniature ; Transplantation, Autologous

OBJECTIVETo compare the efficacy, tolerance and safety between oral sodium phosphate(NaP) and polyethylene glycol(PEG) on bowel preparation.

METHODSOne hundred and fifteen inpatients were randomly divided into NaP group and PEG group. The questionnaire was designed for scoring by patients and doctors regarding to tolerance, taste, side effects and cleaning degree etc.

RESULTSCompared with PEG group, NaP presented better tolerance, lower side effects and higher rate of adequate cleaning quality(P<0.05). NaP could cause electrolytic alterations, such as hyperphosphatemia, hypernatremia, hypocalcemia and hypopotassemia, but these changes were transient and without clinical significance.

CONCLUSIONSodium phosphate is safe and effective for bowel preparation, and is better than polyethylene glycol in tolerance.

Administration, Oral ; Adolescent ; Adult ; Aged ; Aged, 80 and over ; Female ; Humans ; Male ; Middle Aged ; Phosphates ; therapeutic use ; Polyethylene Glycols ; therapeutic use ; Preoperative Care ; methods ; Prospective Studies ; Young Adult

The routine bowel preparation before colorectal surgery usually includes mechanical and medicine preparations, with the original purpose of reducing complications such as anastomosis leakage, wound, and abdominal infections. Many domestic hospitals are still employing the methods of three-day bowel preparation, while in the West, the way of this preparation has dramatically changed. In last decade, one-day preparation has been widely accepted internationally, with two major medications of sodium phosphate and polyethylene glycol frequently used in the clinic. It has also been indicated that excessive mechanical and medicinal bowel preparations exert harmful effects on the combined intestinal barrier, and may result in various complications. A few reports have suggested to omit the mechanical bowel preparation before surgery, which is still under controversy, however, well-designed clinical trials are needed to readjust and regulate the duration and intensity of bowel preparation before colorectal surgery in China.
Colorectal Surgery ; Humans ; Intestinal Mucosa ; physiology ; Phosphates ; adverse effects ; therapeutic use ; Polyethylene Glycols ; adverse effects ; therapeutic use ; Preoperative Care ; adverse effects ; methods

The feasibility of anterior lumbar intervertebral fusion with artificial bone in place of autogenous bone was investigated. Porous hydroxyapatite (HA)/ZrO2 ceramics loading bone morphogenetic protein (BMP) were implanted after removal of lumbar vertebral disc in rabbits. The adjacent intervertebral discs were also removed by the same way and autogenous illic bone was implanted. SEM observation and biomechanical test were carried out. Compound bone had a bit lower osteoinductive activity than autogenous bone by SEM (Osteoinductive activity of artificial bone in 12 weeks was the same as that of autogenous bone in 9 weeks). Biomechanical test revealed that compound bone had lower anti-pull strength than autogenous bone (P < 0.001), but there was no significant difference in anti-pull strength between compound bone at 12th week and autogenous bone at 9th week (P > 0.05). It was concluded that compound bone could be applied for anterior spinal fusion, especially for those patients who can't use autogenous bone.
Biocompatible Materials/therapeutic use ; Bone Morphogenetic Proteins/*therapeutic use ; Calcium Phosphates ; Durapatite ; Hydroxyapatites ; Implants, Experimental ; Intervertebral Disk/surgery ; Lumbar Vertebrae/*surgery ; Spinal Fusion/*methods ; Spinal Injuries/*surgery