Risk factor analysis and construction of prediction models for short-term postoperative complications in patients undergoing gastrointestinal tract surgery.

Purpose: To identify risk factors associated with short-term postoperative complications in patients with gastrointestinal cancer and develop and validate prediction models to predict the probability of complications. Methods: A total of 335 patients enrolled in the primary cohort of this study were divided into training and validation sets in a chronological order. Using univariate and multivariate logistic regression analyses, the risk factors for postoperative complications were determined, and nomogram prediction models were constructed. The performance of the nomogram was assessed with respect to the receiver operator characteristic and calibration curves. Results: Patients with complications had a stronger postoperative stress response and a longer duration of daily fluid intake/output ratio >1 after surgery. Logistic analysis revealed that body mass index (BMI), body temperature on POD4 (T.POD4), neutrophil percentage on POD4 (N.POD4), fasting blood glucose on POD4 (FBG.POD4), and the presence of fluid intake/output ratio <1 within POD4 were risk factors for POD7 complications, and that BMI, T.POD7, N.POD7, FBG.POD4, FBG.POD7, and the duration of daily fluid intake/output ratio >1 were risk factors for POD30 complications. The areas under the curve of Nomogram-A for POD7 complications were 0.867 and 0.833 and those of Nomogram-B for POD30 complications were 0.920 and 0.918 in the primary and validation cohorts, respectively. The calibration curves showed good consistency in both cohorts. Conclusion: This study presented two nomogram models to predict short-term postoperative complications in patients with gastrointestinal cancer. The results could help clinicians identify patients at high risk of complications within POD7 or POD30.

Synthesis of CaO-SiO2-P2O5 mesoporous bioactive glasses with high P2O5 content by evaporation induced self assembly process.

Mesoporous bioactive glasses (MBGs) of the CaO-SiO(2)-P(2)O(5) system containing relatively high P(2)O(5) contents (10-30 mol%) were prepared from a sol-gel. An evaporation-induced self-assembly (EISA) technique was used with poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (EO(20)-PO(70)-EO(20), P123) acting as a template. The structural, morphological and textural properties of MBGs were investigated by small-angle X-ray diffraction (SAXRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and a N(2) sorption/desorption technique. SAXRD and TEM results display the reduced long-range ordering of mesopores with increasing P(2)O(5) content. N(2) sorption/desorption analysis shows that all three samples exhibit a type IV isotherm with type H1 hysteresis loops, characteristic of independent cylindrical slim pore channels and this material has a Barret-Joyner-Halenda (BJH) model pore size of ~4 nm and BET specific surface area ~430 m(2)/g. NMR results indicate a more condensed framework for samples with 30 mol% P(2)O(5) than samples with 10 mol% P(2)O(5). For in vitro bioactivity tests where samples were soaked in simulated body fluid (SBF), samples with 30 mol% P(2)O(5) showed higher crystallinity than those with lower P(2)O(5) contents Silicon concentration increased in SBF solution during the soaking period, which indicates MBGs can be degradable in SBF solution.

The incidence and risk factors of deep venous thrombosis in lower extremities following surgically treated femoral shaft fracture: a retrospective case-control study.

BACKGROUND: There is still a lack of data on deep vein thrombosis (DVT) following surgically treated femoral shaft fracture (FSF). The goal of this study was to investigate the characteristics of postoperative DVT and the association between the occurrence of DVT and risk factors in patients undergoing surgical treatment for FSF. METHODS: This observational retrospective case-control study reviewed 308 patients who received surgical treatment of FSF between January 2016 and October 2020 at a university hospital. Univariate analyses were performed on the data of demographics, comorbidities, laboratory biomarkers, and operation-related indexes. The receiver operating characteristic (ROC) curve analysis, univariate analyses, and multivariate logistic regression analysis were employed to identify the independent risk factors associated with DVT. RESULTS: In total, 308 patients with surgically treated FSF were included, among whom 48 (15.6%) patients had postoperative DVTs. The univariate analyses showing significant differences regarding DVT were American Society of Anesthesiologists (ASA) classification, diabetes mellitus, current smoking, aspartate transaminase (AST), and very-low-density lipoprotein (VLDL) level among the 34 factors. According to the ROC results, the optimal cutoff values for intraoperative blood loss, D-dimer, and age were 350 ml, 1.08 µg/ml, and 35 years, respectively. The multivariable model demonstrated 4 significantly independent associations with postoperative DVT, including current smoking, intraoperative blood loss (> 550 ml), age (> 35 years), and D-dimer > 1.09 µg/ml. CONCLUSION: These risk factors as screening tools contribute to risk stratification of the occurrence of thromboembolic events. In addition, our findings would help orthopedic surgeons make a cross-specialty decision and implement targeted precaution measures for patients with FSF.

Anti-washout carboxymethyl chitosan modified tricalcium silicate bone cement: preparation, mechanical properties and in vitro bioactivity.

Anti-washout CaF(2) stabilized C(3)S (F-C(3)S) bone cement was prepared by adding water-soluble carboxymethyl chitosan (CMCS) to the hydration liquid. The setting time, compressive strength and in vitro bioactivity of the CMCS modified F-C(3)S (CMCS-C(3)S) pastes were evaluated. The results indicate that CMCS-C(3)S pastes could be stable in the shaking simulated body fluid (SBF) after immediately mixed. The addition of CMCS significantly enhances the cohesion of particles, at the same time restrains the penetration of liquid, and thus endows the anti-washout ability. The setting times of the pastes increase with the increase of CMCS concentrations in the hydration liquid. Besides, the compressive strengths of CMCS-C(3)S pastes after setting for 1-28 days are lower than that of the pure F-C(3)S paste, but the sufficient strengths would be suitable for the clinical applications. The crystalline apatite deposited on the paste surface is retarded from 1 to 2 days for the addition of CMCS, but the quantities of deposited apatite are same after soaking in SBF for 3 days. As the result that pure C(3)S paste has shorter setting times than pure F-C(3)S paste, CMCS modified pure C(3)S pastes would have better anti-washout ability. Our study provides a convenient way to use C(3)S bone cement with excellent anti-washout ability when the pastes are exposed to biological fluids. The novel anti-washout CMCS-C(3)S bone cement with suitable setting times, sufficient strengths and in vitro bioactivity would have good prospects for medical application.

High-energy extracorporeal shock wave therapy for early stage femoral head osteonecrosis: A protocol of systematic review.

BACKGROUND: Published trials reported that high-energy extracorporeal shock wave therapy (HEEPSWT) can effectively treat early stage femoral head osteonecrosis (ESFHO). However, their results are still inconsistent. Thus, this study will systematically and comprehensively explore the effectiveness and safety of HEEPSWT for ESFHO. METHODS: We will retrieve the electronic databases of Cochrane Library, EMBASE, PubMed, Web of Science, Cumulative Index to Nursing and Allied Health Literature, VIP database, and China National Knowledge Infrastructure from inception to the present. All randomized controlled trials that focusing on the effectiveness and safety of HEEPSWT for ESFHO will be considered. Two researchers will undertake literature selection, information collection, and risk of bias evaluation separately. If disagreements occur, we will invite a third researcher for consultation and a final decision will be made. Cochrane risk of bias tool, and Grades of Recommendation, Assessment, Development and Evaluation will be utilized to assess the risk of bias and quality of evidence, respectively. We will perform statistical analysis using RevMan 5.3 software. RESULTS: This study will provide a detailed summary of exist evidence related to the effectiveness and safety of HEEPSWT for ESFHO. CONCLUSION: The results of this study synthesize the evidence regarding the HEEPSWT for ESFHO, which may help to guide clinical management in the future. SYSTEMATIC REVIEW REGISTRATION: INPLASY202060055.

Efficacy of artificial femoral head replacement for femoral head avascular necrosis.

BACKGROUND: Femoral head avascular necrosis (FHAN) is one of the most common progressive orthopedic disorders. Previous studies have reported that artificial femoral head replacement (AFHR) can effectively treat patients with FHAN. However, no systematic review has investigated the efficacy of AFHR for FHAN. This study will assess the efficacy of AFHR for patients with FHAN. METHODS: We will search MEDLINE, EMBASE, Web of Science, Cochrane Library, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure up to March 1, 2019 without any restrictions. Any randomized controlled trials for assessing the efficacy of AFHR for patients with FHAN. The methodological quality for each eligible study will be assessed by using Cochrane risk of bias tool. Statistical analysis will be conducted by using RevMan 5.3. RESULTS: This study will provide current evidence of AFHR for patients with FHAN from several aspects, including pain intensity, function, and limitation of femoral head, health-related quality of life, and safety. CONCLUSION: This study will provide latest evidence on assessing the efficacy and safety of AFHR for FHAN.PROSPERO registration number: PROSPERO CRD42019126249.

Effectiveness of neuromuscular electrical stimulation and ibuprofen for pain caused by necrosis of the femoral head: A retrospective study.

This retrospective study analyzed the effectiveness of neuromuscular electrical stimulation (NMES) for pain relief caused by necrosis of femoral head (NFH).Totally, 80 cases of patients with NFH were analyzed and then were assigned to a treatment group or a control group in this study. Of these, 40 cases in the treatment group received ibuprofen and NMES therapy. The other 40 cases in the control group received ibuprofen alone. Cases in both groups were treated for a total of 6 weeks. The primary outcome of pain intensity was measured by a visual analog scale (VAS). The secondary outcome was assessed by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). In addition, adverse events (AEs) were also recorded in each case. All outcomes were evaluated before and after the treatment.After treatment, patients in the treatment group showed more effectiveness in pain relief, as measured by VAS (P < .01) and WOMAC sub-pain scale (P < .01), except stiffness, as evaluated by WOMAC sub-stiffness scale (P = .07), and function, as assessed by WOMAC sub-function scale (P = .09), than patients in the control group. Additionally, no significant differences in AEs were detected between 2 groups.This study found that NMES may be helpful for pain relief in patients with NFH.

Novel highly biodegradable biphasic tricalcium phosphates composed of alpha-tricalcium phosphate and beta-tricalcium phosphate.

Novel biodegradable biphasic tricalcium phosphates (BTCP) composed of alpha-tricalcium phosphate (alpha-TCP) and beta-tricalcium phosphate (beta-TCP) were successfully synthesized by heating amorphous calcium phosphate precursors with different structures at 800 degrees C for 3 h. The ratio of alpha-TCP and beta-TCP in the calcium phosphate particle can be controlled by aging time and pH value during synthesis of the amorphous precursor.

Ultrastrong composite film of Chitosan and silica-coated graphene oxide sheets.

Chitosan (CS) has attracted significant interest in various fields due to its outstanding functional properties (especially, its chain with positive charge). However, wide-range applications of CS are severely limited because of its poor mechanical properties. Ultrastrong composite film of CS and silica-coated graphene oxide sheets (GO@SiO2) were prepared by a simple solution casting method in this article. GO@SiO2 was prepared by the hydrolysis of tetraethyl orthosilicate (TEOS) in GO ethanol solution. Compared with the pure CS film, the tensile strength of the CS/GO@SiO2 composite film with incorporation of 1.75wt% GO@SiO2 fillers was significantly increased 158% from 55±4 to 142±24MPa. Such high tensile strength may be caused synergistically by strong interaction between two components and high crystallinity of the CS matrix. CS based composite with ultrastrong strength may have more potential applications in biomedical fields.

Preparation and characterization of novel alkali-activated nano silica cements for biomedical application.

The major goal of this study was to investigate and characterize novel Ca(OH)(2)-activated nano silica (SiO(2)) cements for the potential application as a bone cement. Novel Ca(OH)(2)-activated nano-SiO(2) powders composed of Ca(OH)(2) and nano-SiO(2) were easily prepared, and the deionized water was used as the liquid phase. The initial and final setting times of Ca(OH)(2)-activated nano-SiO(2) cements with liquid to powder (L/P) ratios of 1.00-1.33 mL g(-1) range from 50 ± 1 to 120 ± 3 min and 96 ± 2 to 190 ± 5 min, respectively. The calorimetric curves indicate that the heat liberations of Ca(OH)(2)-activated nano-SiO(2) cements (105.57-138.01 J g(-1)) are lower than that of C(3)S (about 150 J g(-1)). The Ca(OH)(2)-activated nano-SiO(2) pastes are injectable under general extrusion force of 100 N, and their compressive strengths with suitable L/P ratios are 5-9 MPa, which is comparable with that of cancellous bone. The in vitro bioactivity of the Ca(OH)(2)-activated nano-SiO(2) cement pastes were investigated by soaking in simulated body fluid for various periods. The results show amorphous apatite deposits on the paste surfaces after soaking in simulated body fluid for 2 h. With the prolonged soaking time, amorphous apatite transforms into crystalline apatite after soaking for 1 day. The Ca(OH)(2)-activated nano-SiO(2) cements have short setting times, low heat liberation, injectability, suitable compressive strength, and excellent in vitro bioactivity, and may be used as bioactive bone cements for bone regeneration.

Preparation and characterization of novel biphasic calcium phosphate powders (alpha-TCP/HA) derived from carbonated amorphous calcium phosphates.

Novel biphasic calcium phosphate (BCP) powders composed of alpha-tricalcium phosphate (alpha-TCP) and hydroxyapatite (HA) were prepared by thermal decomposition of carbonated amorphous calcium phosphates (CACP). At first, the CACP precipitates were synthesized by adding ammonium carbonate in the presence of poly(ethylene glycol) at pH 10 with an initial Ca/P molar ratio of 1.60 at 5 degrees C. The Ca/P molar ratios of the CACP precursors are between 1.50 and 1.67 investigated by ICP. Then BCP (alpha-TCP/HA) powders were obtained after heating the CACP precursors at relatively low temperature (800 degrees C) for 3 h. alpha-TCP/HA powders were characterized by X-ray diffractometry, Fourier transform infrared spectra, transmission electron microscopy/scanning electron microscopy, and sedimentation experiment. The results show that alpha-TCP and HA phases form in one powder, alpha-TCP/HA powders are sphere with the diameter of 300 nm to less than 100 nm varied with their chemical compositions and the ratio of alpha-TCP and HA in the powders can be adjusted by the adding amount of carbonates. The possible formation process of biphasic alpha-TCP/HA powders was proposed.

The apatite formation ability of CaF2 doping tricalcium silicates in simulated body fluid.

The purpose of this study was to investigate the effects of CaF(2) on the apatite formation ability of tricalcium silicates (Ca(3)SiO(5), C(3)S) and the mechanism of apatite formation on C(3)S pastes. Different amounts of CaF(2) (0, 1, 2 and 3 wt%) were mixed in the raw materials during the synthesis process of C(3)S. The apatite formation ability of the CaF(2) doping C(3)S was examined by soaking the one-day setting pastes in simulated body fluid (SBF). The fluoride concentrations, pH values, structural and morphological variations of the pastes were examined during soaking in SBF. With the addition of CaF(2), the initial crystalline apatite formation time of the pastes was decreased from three days to one day. After soaking for seven days, the thicknesses of apatite layers depositing on the surface of C(3)S doped with 0, 1, 2 and 3 wt% CaF(2) were about 88, 102, 168 and 136 microm, respectively. C(3)S doped with 2 wt% CaF(2) showed the better ability to induce the formation of apatite. Furthermore, the mechanism of the apatite formation of the CaF(2) doping C(3)S pastes may be attributed to the formation and stability of F-substituted apatite determined by x-ray photoelectron spectroscopy (XPS) at the early age. The results indicated that CaF(2) doping C(3)S has better in vitro bioactivity, and may be used to prepare novel bone cement.

Surface modification of hydroxyapatite by stearic acid: characterization and in vitro behaviors.

Hydroxyapatite was modified by stearic acid (Sa) in the organic mediated solution using a reflux setup. Activation ratio was introduced to characterize the effect of organic solvents, reaction times and adding amounts of Sa. HA before and after surface modification were investigated by XRD, FTIR, particle size distribution, TEM and ICP. The optimal adding amount of Sa is about 3 wt%, and there are Sa molecules on the surface of HA with a chemical reaction between HA and Sa. Sa did not change the phases and particle size of HA. HA after modified has good bioactivity in vitro. Sa has great potential as surface modifier to improve the properties of inorganic fillers in the organic matrix.

In vitro synthesis and characterization of amorphous calcium phosphates with various Ca/P atomic ratios.

Amorphous calcium phosphates (ACP) were synthesized utilizing poly(ethylene glycol) as stabilizing additive at low temperature. Effects of aging time, pH value, reactant and initial Ca/P atomic ratio on the phase and chemical composition of calcium phosphate precipitates were investigated by powder X-ray diffraction and induced coupled plasma atomic spectroscopy. It was found that ACP could be stabilized by poly(ethylene glycol) in the mother solution for more than 18 h at 5 degrees C, and Ca/P atomic ratios of ACP precipitates could be adjusted from 1.33 to 1.50 by controlling pH values and initial Ca/P atomic ratios. ACP precipitates were characterized by thermal gravity analysis, Fourier transform infrared spectroscopy, scanning electron microscopy and energy dispersive spectrum. The results show that there is 4 wt% poly(ethylene glycol) in ACP powders without any contaminated ions, and the spherical particle size of ACP powders is 60 approximately 70 nm in the diameter with uniform size distribution which endows it as a potential precursor to prepare crystalline calcium phosphate phases. ACP has potential to be used as biodegradable and/or bioresorbable biomaterials and tissue engineering scaffold.