Reasons and Risk Factors for Failed Same-Day Discharge After Total Joint Arthroplasty

BACKGROUND

A shift toward same-day discharge (SDD) in primary elective total knee arthroplasty (TKA) and total hip arthroplasty (THA) has created a need to optimize patient selection and improve same-day recovery pathways. The objectives of this study were (1) to identify our institution's most common causes for failed SDD, and (2) to evaluate risk factors associated with failed SDD.

METHODS

A retrospective review of SDD patients undergoing primary TKA or THA from January 2021 to September 2022 was conducted. Reasons for SDD failure were recorded and differences between successful and failed SDD cases were assessed via a multivariate logistic regression.

RESULTS

Overall, 85.3% (651 of 753) of patients included were successful SDDs. Failed SDD occurred in 16.8% (74 of 441) of TKA and 11.8% (38 of 322) of THA cases. Primary reasons included failure to clear physical therapy (33.0%, 37 of 112), postoperative hypotension (20.5%, 23 of 112), and urinary retention (16.9%, 19 of 112). Analysis revealed that overall failed SDD cases were more likely to have had prior opioid use and a longer surgical time. Failed TKA SDD cases were more likely to have had a longer surgical time and not have receive a preoperative nerve block, while failed THA SDD cases were more likely to be older.

CONCLUSIONS

The SDD selection criteria and pathways continue to evolve, with multiple factors contributing to failed SDD. Improving patient selection algorithms and optimizing post-operative pathways can enhance the ability to successfully choose SDD candidates.

LEVEL OF EVIDENCE

III.

[Association between HBV viral load and severity of liver inflammation in patients with chronic hepatitis B virus infection]

Objective: To explore the relationship and dynamic changes between virological markers and hepatic pathological damage due to host anti-hepatitis B virus (HBV) immunity in the natural course of disease in chronic HBV infected patients. Methods: Two hundred and thirty-eight adult chronic HBV-infected patients who underwent liver biopsy from January 2016 to June 2022 in Taizhou Hospital, Zhejiang Province, were retrospectively selected. General clinical data such as age, gender, platelets, ALT, AST, albumin, HBV DNA, qHBsAg, HBeAg, and liver pathology diagnostic indexes such as the grade of liver necroinflammation and liver fibrotic stages of the patients were collected. The patients were grouped according to HBeAg status, and subgrouped according to different grades of liver necroinflammation and different HBV DNA loads. Statistical analyses were performed to compare the differences in HBV virologic marker levels between the groups, and the correlation between them and the indicators of hepatic inflammatory injury, such as ALT,AST, and the grade of liver necroinflammation in the patients. Results: The levels of HBV virological markers in HBeAg-positive patients with moderate or higher liver necroinflammatory grade (G≥2) were significantly lower than those with mild (no) liver necroinflammatory grade (G < 2) (P < 0.01); whereas the opposite trend was observed in HBeAg-negative patients, with the levels of HBV DNA, and qHBsAg in the G≥2 subgroup being significantly higher than those in the G < 2 subgroup (P < 0.01). Correspondingly, HBV DNA level and qHBsAg showed weak to moderately strong negative correlation with liver necroinflammatory grade and AST which was an indicator of hepatic inflammatory injury in HBeAg-positive patients (P < 0.05); whereas in HBeAg-negative patients, they showed weak to moderately strong positive correlation with hepatic inflammatory activity and ALT, AST (P < 0.001), in which qHBsAg showed only a weak positive correlation with patients' liver necroinflammatory grade (P = 0.003). Further subgroup analyses of HBeAg-positive patients according to whether the HBV DNA level was > 2×10(6) IU/ml showed weak to moderate negative correlations between HBV virological markers and liver necroinflammatory grade as well as ALT and AST in the subgroup of patients with HBV DNA > 2×10(6) IU/ml (P < 0.05); however, the negative correlation disappeared in patients who were still HBeAg positive and had HBV DNA ≤ 2×10(6) IU/ml. Moreover, HBV DNA and ALT, HBeAg and AST showed moderate positive correlation (P < 0.05). Conclusion: We speculate that the activation of host anti-HBV immunity can efficiently inhibit HBV replication by targeting the infected hepatocytes, but only in the early phase of disease progression in HBeAg positive patients with HBV DNA high (> 2×10(6) IU/ml).

Antioxidant 1 copper chaperone gene expression and copper levels in dog osteosarcoma patients

Twenty-four dogs with OS underwent limb amputation. Serum, OS tumour, and normal bone were harvested at time of surgery. RNA was extracted and gene expression was performed using quantitative polymerase chain reaction (qPCR). Tissue and blood copper concentrations were also determined with spectrophotometry. Compared to bone, tumour samples had significantly higher expressions of antioxidant 1 copper chaperone (ATOX1, p = .0003). OS tumour copper levels were significantly higher than that of serum (p < .010) and bone (p = .038). Similar to our previous observations in mouse and human OS, dog OS demonstrates overexpression of genes that regulate copper metabolism (ATOX1), and subsequent copper levels. Dogs with OS may provide a robust comparative oncology platform for the further study of these factors, as well as potential pharmacologic interventions.

[Correlation analysis between prenatal exposure of per-/polyfluoroalkyl compounds and neonatal outcome]

Objective: To investigate the correlation between the prenatal exposure of per-/polyfluoroalkyl substances (PFASs) and the neonatal outcome. Methods: A total of 506 maternal infant cohort samples were collected in Hangzhou, Zhejiang province from 2020 to 2021. The exposure levels of seven PFASs in maternal serum before delivery were detected by solid-phase extraction-ultra performance liquid chromatography tandem mass spectrometry. Multivariable linear regression model was used to analyze the influence of prenatal exposure of PFASs on birth weight, birth length and Apgar score. Results: The maternal age, prenatal body mass index and gestation age were (31.3±4.3) years old, (26.7±3.2) kg/m² and (265.0±28.3) days, respectively. The birth weight, birth length and scores of Apgar-1 and Apgar-5 were (3.1±0.8) kg, (49.3±2.9) cm, (9.88±0.47) points and (9.99±0.13) points, respectively. PFASs were widely distributed in maternal serum, with the highest concentration of (18.453±19.557) ng/ml, (6.756±9.379) ng/ml and (5.057±8.555) ng/ml for perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS) and 6∶2 chlorinated polyfluorinated ether sulfonate (Cl-PFESA), respectively. Maternal age, parity and delivery mode were associated with the exposure level of PFASs (P<0.05). Subgroup analysis showed that PFOS had negative effects on birth weight (β=-0.958), birth length (β=-0.073) and Apgar-5 score (β=-0.288) for neonates in the low birth weight (LBW) group. 6∶2 Cl-PFESA and 8∶2 Cl-PFESA inhibited the birth weight (β=-0.926; β=-0.552) and length (β=-0.074; β=-0.045) of newborn in the LBW group. In addition, 4∶2 fluorotelomer sulfonate (FTS) was associated with increased birth weight (β=0.111) and decreased Apgar-5 score (β=-0.030) in the normal weight group. Conclusion: Prenatal exposure to PFASs is associated with birth weight, birth length and Apgar-5 score. It is necessary to continue to pay attention to the impact of PFASs on fetal growth and development through maternal-fetal transmission.

Superficial mycosis, at the site or distant to the surgical site, appears to predispose patients to bacterial periprosthetic joint infections

BACKGROUND

It is traditionally believed that presence of fungal infection in the nail or skin of patients is a risk factor for subsequent infection. The literature is devoid of any evidence to confirm or refute this belief. This study examined a possible relationship between the presence of superficial skin or nail mycoses and subsequent periprosthetic joint infection (PJI) in patients undergoing total joint arthroplasty (TJA).

METHODS

This is a single-centre, retrospective study of patients who underwent primary TJA between 2000 and 2018. 55 patients with superficial mycoses of skin or nail, at the time of arthroplasty were identified and a variable number matching with up to a 1:5 ratio was performed with 182 patients undergoing TJA who had no superficial mycosis. The groups were further divided into knee and hip TJA. The outcome of TJA in the cohorts was compared.

RESULTS

Preoperative demographics were similar between the 2 groups. The incidence of PJI in patients undergoing TKA within a year was significantly higher in patients with superficial mycosis at 8.6% (3/35) compared to 0% (0/120) in patients without mycosis. However, all infections were caused by bacterial species and none were fungal. Multiple regression analysis demonstrated that the presence of superficial mycosis had a strong correlation with development of PJI postoperatively in our TKA cohort.

CONCLUSIONS

Identification of fungal infection (mycosis) of skin and nail in patients awaiting TJA is important. These patients appear to have a higher risk for developing bacterial PJI than those without fungal infections. Further study is needed to determine if treatment of these patients prior to arthroplasty stands to reverse the high risk for PJI that these patients carry.

Intraoperative Evaluation of Soft Tissue Sarcoma Surgical Margins with Indocyanine Green Fluorescence Imaging

Soft tissue sarcomas (STS) are rare malignant tumors often associated with poor outcomes and high local recurrence rates. Current tools for intraoperative and definitive margin assessment include intraoperative frozen section and permanent pathology, respectively. Indocyanine green dye (ICG) is a historically safe fluorophore dye that has demonstrated efficacy for intraoperative margin assessment in the surgical management of both breast and gastrointestinal cancers. The utility of ICG in the surgical management of sarcoma surgery has primarily been studied in pre-clinical mouse models and warrants further investigation as a potential adjunct to achieving negative margins. This study is a prospective, non-randomized clinical study conducted on patients with confirmed or suspected STS. Patients younger than 18 years, with a prior adverse reaction to iodine or fluorescein, or with renal disease were excluded from the study. Intravenous ICG was infused approximately three hours prior to surgery at a dosage of 2.0-2.5 mg/kg, and following tumor resection, the excised tumor and tumor bed were imaged for fluorescence intensity. When scanning the tumor bed, a threshold of 77% calibrated to the region of maximum intensity in the resected tumor was defined as a positive ICG margin, according to published protocols from the breast cancer literature. ICG results were then compared with the surgeon's clinical impression of margin status and permanent pathology results. Out of 26 subjects recruited for the original study, 18 soft tissue sarcomas (STS) were included for analysis. Three subjects were excluded for having bone sarcomas, and five subjects were excluded due to final pathology, which was ultimately inconsistent with sarcoma. The average age of patients was 64.1 years old (range: 28-83), with an average ICG dose of 201.8 mg. In 56% (10/18) of patients, ICG margins were consistent with the permanent pathology margins, with 89% specificity. The use of ICG as an intraoperative adjunct to obtaining negative margins in soft tissue sarcoma surgery is promising. However, studies with larger sample sizes are warranted to further delineate the accuracy, optimal dosage, timing, and types of sarcoma in which this diagnostic tool may be most useful.

Short-Term Outcomes Are Comparable between Robotic-Arm Assisted and Traditional Total Knee Arthroplasty

Robotic-arm assisted total knee arthroplasty (rTKA) was developed to provide for increased accuracy of component placement compared with conventional manual TKA (mTKA). Whether or not rTKA is cost-effective in a bundled payment model has yet to be addressed. The purpose of this comparative study was to evaluate the short-term clinical outcomes of rTKA and mTKA. We retrospectively reviewed a series of 4,086 consecutive primary TKA performed by one of five surgeons across six different hospitals at our institution from January 2016 to December 2018. Outcomes for rTKA cases (n = 581) and mTKA cases (n = 3,505) were compared using unmatched multivariate analysis and a matched cohort. We analyzed 90-day outcomes, episode-of-care claims data, and short form (SF-12) outcome scores to 2 years postoperatively. In matched bivariate analysis, there was no difference in episode-of-care costs, postacute care costs, complications, 90-day readmission rates, emergency department/urgent care visits, reoperations, and mortality between rTKA and mTKA patients (p > 0.05). Matched patients undergoing rTKA did have a shorter hospital length of stay (1.46 vs. 1.80 days, p < 0.001) and decreased rates of discharge to rehabilitation facilities (5.5 vs. 14.8%, p < 0.001). SF-12 scores were clinically similar. Multivariate analysis demonstrated no differences in any 90-day outcome. We conclude that patients undergoing rTKA have comparable costs, 90-day outcomes, and clinically similar improvements in functional outcome scores compared with mTKA patients. Further study is needed to determine whether rTKA will result in improved implant survivorship and long-term functional outcomes (Level of evidence III).

Risk of Gastrointestinal Bleeding With Extended Use of Nonsteroidal Anti-Inflammatory Drug Analgesia After Joint Arthroplasty

BACKGROUND

Chronic nonsteroidal anti-inflammatory drug (NSAID) use is associated with gastrointestinal bleeding via inhibition of endogenous mucosal protection and platelet aggregation. This study aimed to determine whether extended NSAIDs after joint arthroplasty is associated with increased risk of gastrointestinal bleeding.

METHODS

This was a retrospective study examining 28,794 adults who underwent joint arthroplasty by one of 50 surgeons from 2016 to 2018. Episodes of gastrointestinal bleeding within 90 days postoperatively were identified prospectively. Postoperative medications were reported directly by patients with electronic questionnaires. The primary analysis was performed using binary logistic regression.

RESULTS

A total of 74 (0.26%) episodes of gastrointestinal bleeding occurred within 90 days (median 8 days) postoperatively. Of 5086 patients with complete data included in the primary analysis, 59.6% had used NSAIDs with median duration of 2 weeks (interquartile range, 0-6 weeks). Patients with gastrointestinal bleeding were significantly older (71.3 vs 67.0 years), required longer hospitalizations (2.1 vs 1.5 days), and more commonly had a history of peptic ulcers (10.8% vs 0.9%). However, there was no positive association between NSAID use and gastrointestinal bleeding. In fact, the odds of gastrointestinal bleeding were lower in patients taking NSAIDs. Gastrointestinal bleeding was associated with anticoagulants, antiplatelet agents, and, to a lesser extent, aspirin.

CONCLUSION

NSAIDs were not associated with gastrointestinal bleeding and may be prescribed safely for a majority of patients after joint arthroplasty. The greatest odds of gastrointestinal bleeding occurred in patients with peptic ulcer disease and those who received antiplatelet and anticoagulation agents. Increasing age and bilateral surgery were also associated with gastrointestinal bleeding.

LEVEL OF EVIDENCE

Level III.

Dual Mobility and Conventional Bearings Have Comparably Low Dislocation Rates for Anterior-Based Approaches in Total Hip Arthroplasty

BACKGROUND

Dual mobility (DM) bearings for total hip arthroplasty (THA) have been proposed to reduce the risk of instability in select patients, especially those undergoing revision surgery. The use of DM bearings has not been studied as extensively for use in primary THA. The purpose of this study is to compare outcomes following primary THA with anterior-based approaches between patients receiving DM bearings vs standard bearing hip implants.

METHODS

We retrospectively reviewed a consecutive series of patients undergoing primary THA through an anterior-based approach. A 3:1 propensity score match was performed between the standard and DM bearing patients to control for possible risk factors for instability. Functional outcomes, dislocations, and aseptic revisions were identified for each patient. The effect of DM on postoperative outcomes was determined using univariate statistical analyses.

RESULTS

In total, 250 DM bearings were compared to 753 standard bearings. We found no difference in dislocation rate between single bearings and DM bearings (0.53% vs 0.4%). There was 1 DM dislocation occurring in a liner with outer diameter of 38 mm. There were no DM dislocations with outer diameter >38 mm. Aseptic revision surgery was more common in DM. This difference was driven by higher incidence of femoral periprosthetic fracture. There were no differences in functional outcomes.

CONCLUSION

Dislocation rates are comparably low between DM bearings and standard bearings for THA done using an anterior approach to the hip. Further investigation is needed to determine if specific patient populations may benefit from DM implants for primary THA when an anterior approach to the hip is being used.

Radiographic Measures of Spinal Alignment Are Not Predictive of the Development of C5 Palsy Following Anterior Cervical Discectomy and Fusion Surgery

BACKGROUND

Postoperative C5 palsy is a common complication following cervical decompression, occurring more frequently after posterior-based procedures. It has been theorized that this is the result of C5 nerve stretch resulting from spinal cord drift with these procedures. As such, it is thought to be less common after anterior cervical decompression and fusion (ACDF). However, no consensus has been reached on its true etiology. The purpose of this study is to assess the rate of C5 palsy following ACDF and to determine whether any radiographic or demographic parameters were predictive of its development.

METHODS

Two hundred and twenty-six patients who received ACDF between September 2015 and September 2016 were reviewed, and 122 were included in the final analysis. Patient demographic, surgical, and radiographic data were analyzed, including preoperative and postoperative radiographic and motor examination results. The Mann-Whitney U test was used to compare continuous variables between independent groups, and Fisher's exact test was used to compare categorical variables between groups.

RESULTS

Seven patients developed a C5 palsy in the postoperative period, an incidence rate of 5.7%. Among the radiographic parameters evaluated, there were no statistically significant differences between the C5 palsy and nonpalsy groups. Additionally, there were no statistically significant differences in age, patient sex, or numbers of vertebral levels fused between groups.

CONCLUSIONS

Ultimately, we did not identify any statistically significant demographic or radiographic predictive factors for the development of C5 palsy following ACDF surgery.

LEVEL OF EVIDENCE

3.

Mitochondrial DNA Heteroplasmy of Hair Shaft Using HID Ion GeneStudioTM S5 Sequencing System

Objective To study the heteroplasmy of the whole mitochondrial genome genotyping result of hair shaft samples using HID Ion GeneStudio^TM S5 Sequencing System. Methods The buccal swabs and blood of 8 unrelated individuals, and hair shaft samples from different parts of the same individual were collected. Amplification of whole mitochondrial genome was performed using Precision ID mtDNA Whole Genome Panel. Analysis and detection of whole mitochondrial genome were carried out using the HID Ion GeneStudio^TM S5 Sequencing System. Results The mitochondrial DNA sequences in temporal hair shaft samples from 2 individuals showed heteroplasmy, while whole mitochondrial genome genotyping results of buccal swabs, blood, and hair samples from the other 6 unrelated individuals were consistent. A total of 119 base variations were observed from the 8 unrelated individuals. The numbers of variable sites of the individuals were 29, 40, 38, 35, 13, 36, 40 and 35, respectively. Conclusion Sequence polymorphism can be fully understood using HID Ion GeneStudio^TM S5 Sequencing system.

[Characteristic and clinical significance of microRNA expression between 144 Uygur and Han women with endometrial carcinoma]

OBJECTIVE

To compare the expression patterns of microRNA (miRNA) between 144 Uygur and Han women with endometrial carcinoma and to investigate their clinical significance.

METHODS

Taqman miRNA low-density array was used to compare miRNA profiles between Uygur and Han women with non-endometrioid endometrial carcinoma (NEEC). Five miRNAs were further analyzed in the 144 endometrial cancers including 62 Uygur and 82 Han samples via real-time PCR to determine their expression patterns.

RESULTS

MiRNA expression profiles revealed that many miRNAs overexpressed or downregula-ted in one ethnic group, but did not express or changed slightly in the other ethnic group. Further detection in the 144 endometrial cancers showed that miR-141, miR-200a, and miR-205 overexpressed in both ethnic groups. In Uygur endometrioid endometrial carcinoma (EEC), tumors with miR-141/200a overexpression tended to be more aggressive in behavior, whereas in the Han group, EEC with miR-200a overexpression was relative mild. However, the NEEC with miR-200a overexpression also had aggressive clinicopathologic features in the Han women. MiR-145 and miR-143 expressed differentially between Uygur and Han groups, they overexpressed in the former and decreased in the latter (P<0.05). In the Uygur women miR-145/143 increased significantly in NEEC and there was a trend that NEEC exhibiting favorable clinicopathologic factors had higher miR-145 expression, and was statistically significant in tumors with myometrial invasion less than 1/2 thickness (P=0.042). By contrary, miR-145/143 decreased in Han group and EEC with worse clinicopathologic variables had lower expression although without statistical significance. NEEC in Han group had no such tendency.

CONCLUSION

Uygur and Han women might have different miRNA expression profiles. MiR-141/200a/205 overexpressed in endometrial carcinomas and miR-141/200a might behave differently between these two ethnic groups as well as in EEC and in NEEC. Although miR-145/143 showed inverse expression patterns between Uygur and Han women with endometrial cancer, they all exerted tumor suppression effect on endometrial cancer.

Tranexamic Acid Reduces the Rate of Periprosthetic Joint Infection After Aseptic Revision Arthroplasty

BACKGROUND

Revision total joint arthroplasty (TJA) has a higher rate of periprosthetic joint infection (PJI) compared with primary TJA, possibly as the result of increased allogeneic blood transfusion. Tranexamic acid (TXA) is gaining popularity in revision TJA to minimize blood loss and the need for transfusion; however, its effect on PJI reduction has yet to be investigated. The hypothesis of this study was that the administration of TXA during revision arthroplasty is protective against subsequent PJI.

METHODS

A prospectively maintained institutional database was used to identify patients who underwent revision TJA for aseptic failure from 2009 to 2018 and had a minimum follow-up of 90 days. Patients who developed PJI following revision arthroplasty were identified. All patients with PJI met Musculoskeletal Infection Society (MSIS) criteria. A multivariate analysis was performed to identify variables independently associated with PJI after aseptic revision TJA.

RESULTS

Overall, 1,731 patients who underwent aseptic revision were identified; of these patients, 83 (4.8%) developed PJI. Patients who received TXA had significantly lower rates (p = 0.029) of PJI postoperatively at 3.30% compared with those who did not receive TXA at 5.73%. After controlling for relevant confounding variables, TXA remained a significant independent factor that protected against PJI (odds ratio [OR], 0.47 [95% confidence interval (CI), 0.23 to 0.90]; p = 0.030). Female sex was also identified as a significant independent factor that protected against PJI (OR, 0.52 [95% CI, 0.30 to 0.88]; p = 0.016). However, preoperative anemia was independently associated with an increased risk of subsequent PJI (OR, 2.37 [95% CI, 1.34 to 4.16]; p = 0.003).

CONCLUSIONS

Based on this study conducted at a single institution, the use of TXA during aseptic revision arthroplasty was independently associated with a reduced risk of subsequent acute PJI after adjusting for multiple patient characteristics and surgical factors.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Long noncoding RNA GAS5 enhanced by curcumin relieves poststroke depression by targeting miR-10b/BDNF in rats

The treatment for post-stroke depression (PSD) is mainly based on a therapeutic strategy combining anti-stroke and anti-depressant drugs. In the present study, the therapeutic effect of curcumin on rats with PSD was detected by open field tests and tail suspension tests, as well as the examination of corticosterone and corticotropin-releasing hormone (CRH) levels in the serum and neurotransmitter 5-hydroxytryptamine (5-HT), 5-hydroxyindoleacetic acid (5-HIAA) and dopamine (DA) levels in the hippocampus. Curcumin notably alleviated depression compared to the controls. Furthermore, long noncoding RNA growth arrest-specific transcript 5 (GAS5) enhanced by curcumin contributed to activation of the BDNF/Trkβ signaling pathway to promote the expression of synaptic-related proteins. GAS5 was demonstrated to function as a sponge of miR-10b. GAS5 upregulation by curcumin could reduce miR-10b to compromise the BDNF mRNA levels. Taken together, these results revealed a novel mechanism of curcumin on PSD through the GAS5/miR-10b/BDNF regulatory axis.

Is Treatment of Periprosthetic Joint Infection Improving Over Time?

BACKGROUND

It is unknown whether the outcomes of treatment for periprosthetic joint infection (PJI) are improving with time. This study evaluated trends in PJI treatment outcomes in the hip and knee following 2-stage exchange arthroplasty and irrigation and debridement (I&D) over the last 17 years.

METHODS

We reviewed 550 two-stage exchange arthroplasties and 194 I&Ds between 2000 and 2016 at our institution. Treatment success was defined according to the Delphi consensus criteria and Kaplan-Meier survivorship curves were generated. A multivariate Cox proportional hazards regression model was generated to determine time trends in the outcome of PJI treatment with the year of surgery included as both a continuous covariate (per 1-year increase) and a categorical covariate (2000-2010 or 2011-2016).

RESULTS

The survivorship of I&D, 2-stage revision, and the total combined cohort were comparable between 2000-2010 and 2011-2016 groups. Multivariate Cox regression analysis showed that the year of surgery was not associated with treatment failure following an I&D or 2-stage exchange arthroplasty, and neither did it increase the risk of non-reimplantation. When year of surgery was considered as a categorical variable, there remained no significant difference in treatment failure following an I&D or 2-stage exchange arthroplasty between the 2000-2010 cohort and 2011-2016 cohort.

CONCLUSION

Despite the increasing clinical focus, research advances, and growing literature relating to PJI, we were unable to detect any substantial improvement in the treatment success rates of PJI at our institution over the 17 years examined in this study. Novel treatments and techniques are certainly needed as current and prior strategies remain far from optimal.

Highlighting the Roles of Anemia and Aspirin in Predicting Ninety-Day Readmission Following Aseptic Revision Total Joint Arthroplasty

BACKGROUND

Revision total joint arthroplasties (TJAs) are associated with an increased rate of complications. To date, it is unclear what drives readmission after aseptic revision arthroplasty and what measures can be taken to possibly avoid them. The purpose of this study is to (1) determine the reasons for readmission after aseptic revision TJA and (2) identify patient-specific or postoperative risk factors through a multivariate analysis.

METHODS

A retrospective study examined 1503 cases of aseptic revision TJA between 2009 and 2016 at an urban tertiary care hospital. Eighty-seven cases (5.8%) of readmission within 90 days of index surgery were identified. Bivariate and multivariate analyses were performed to assess independent risk factors for readmission.

RESULTS

The reasons for readmission were infection (38%), wound complications (22%), and dislocation/instability of the prosthetic joint (13%). Only preoperative anemia was associated with an increased odds ratio (OR) of readmission (OR 1.82, 95% confidence interval [CI] 1.126-2.970, P = .015), whereas postoperative venous thromboembolism prophylaxis with aspirin (OR 0.58, 90% CI 0.340-0.974, P = .039) and discharge to an inpatient rehab facility (OR 0.22, 95% CI 0.051-0.950, P = .042) were associated with significantly lower odds of readmission.

CONCLUSION

Based on this single institutional study, addressing preoperative anemia and considering the implementation of aspirin for venous thromboembolism prophylaxis may be 2 targets to potentially reduce readmission after aseptic revision TJA.

Clinical practice guideline for image-guided multimode tumour ablation therapy in hepatic malignant tumours

Multimode tumour ablation therapy is a treatment method that combines cryoablation with radiofrequency ablation, guided by medical imaging technology and based on precise planning, targeting, monitoring, and control of the thermal energy delivered, with the aim of achieving a whole-body antitumour immune response to malignant tumours. To develop standardized criteria for the application of multimode tumour ablation therapy to malignant hepatic tumours, to facilitate actualization of the criteria in various hospitals, and to ensure therapeutic efficacy and safety, the Society of Interventional Therapy of the Chinese Anti-Cancer Association and the Solid Tumor Theranostics Committee of the Shanghai Anti-Cancer Association assembled experts who specialize in oncology to discuss this treatment method and to arrive at a clinical practice consensus guideline for the indications, contraindications, and techniques of multimode tumour ablation therapy for malignant hepatic tumours.

The Efficacy of Liposomal Bupivacaine Over Traditional Local Anesthetics in Periarticular Infiltration and Regional Anesthesia During Total Knee Arthroplasty: A Systematic Review and Meta-Analysis

BACKGROUND

Since its Food and Drug Administration approval in 2011 as a local anesthetic for postsurgical analgesia, liposomal bupivacaine (LB) has been incorporated into the periarticular injection (PAI) of many knee surgeons. The slow release of this medication from vesicles should significantly extend the duration of its analgesic effect, but current evidence has not clearly demonstrated this benefit.

METHODS

We systematically searched electronic databases including PubMed, MEDLINE, Cochrane Library, EMBASE, ScienceDirect, and Scopus, as well as the Journal of Arthroplasty web page for relevant articles. All calculations were made using Review Manager 5.3.

RESULTS

We identified 42 studies that compared LB to an alternate analgesic modality. Seventeen of these studies were controlled trials that were included in meta-analysis. Significant differences were seen in pain scores with LB over a peripheral nerve block (mean difference = 0.45, P = .02) and LB over a traditional PAI (standard mean difference = -0.08, P = .004).

CONCLUSION

While LB may offer a statistically significant benefit over a traditional PAI, the increase in pain control may not be clinically significant and it does not appear to offer a benefit in reducing opioid consumption. However, there is no standardization among current studies, as they vary greatly in design, infiltration technique, and outcome measurement, which precludes any reliable summarization of their results. Future independent studies using a standardized protocol are needed to provide clear unbiased evidence.

Assessment of the cryoablation margin using MRI-CT fusion imaging in hepatic malignancies

AIM

To demonstrate the feasibility of magnetic resonance imaging (MRI)-computed tomography (CT) fusion imaging for the assessment of the ablative margin after cryoablation in hepatic malignancies.

MATERIALS AND METHODS

This retrospective study analysed 35 patients with 47 liver tumours treated with CT-guided cryoablation. Fusion images of pre-ablation MRI and intraoperative CT data were created on a workstation. Minimal ablative margin (MAM) assessment was categorised into three groups: (I) MAM <0 mm (tumour protruded through the ablation zone), (II) MAM 0-5 mm, and (III) MAM ≥5 mm. Local tumour progression (LTP) was assessed during follow-up.

RESULTS

MRI-CT fusion imaging was successfully achieved in 46 (97.9%) of 47 lesions. LTP was detected in 67.4% (31/46) of cases. Twenty-four (77.4%) of 31 LTPs occurred in the subcapsular region of the liver. Using fusion images, the MAM was classified as groups I, II, and III in 18, 25, and three tumours, respectively. In group I, LTP was found in 15 (83.3%) of 18 lesions, whereas in group II, LTP was detected in 16 (64%) of 25 lesions. The cumulative LTP rate in group II was significantly lower than that in group I (p=0.012).

CONCLUSION

Pre-ablation MRI and intraoperative CT fusion imaging is feasible and useful for evaluating the MAM of cryoablation in hepatic malignancies.

2018 international consensus meeting on musculoskeletal infection: Summary from the biofilm workgroup and consensus on biofilm related musculoskeletal infections

Biofilm-associated implant-related bone and joint infections are clinically important due to the extensive morbidity, cost of care and socioeconomic burden that they cause. Research in the field of biofilms has expanded in the past two decades, however, there is still an immense knowledge gap related to many clinical challenges of these biofilm-associated infections. This subject was assigned to the Biofilm Workgroup during the second International Consensus Meeting on Musculoskeletal Infection held in Philadelphia USA (ICM 2018) (https://icmphilly.com). The main objective of the Biofilm Workgroup was to prepare a consensus document based on a review of the literature, prepared responses, discussion, and vote on thirteen biofilm related questions. The Workgroup commenced discussing and refining responses prepared before the meeting on day one using Delphi methodology, followed by a tally of responses using an anonymized voting system on the second day of ICM 2018. The Working group derived consensus on information about biofilms deemed relevant to clinical practice, pertaining to: (1) surface modifications to prevent/inhibit biofilm formation; (2) therapies to prevent and treat biofilm infections; (3) polymicrobial biofilms; (4) diagnostics to detect active and dormant biofilm in patients; (5) methods to establish minimal biofilm eradication concentration for biofilm bacteria; and (6) novel anti-infectives that are effective against biofilm bacteria. It was also noted that biomedical research funding agencies and the pharmaceutical industry should recognize these areas as priorities. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

Outcomes of distal femoral fractures treated with minimally invasive plate osteosynthesis versus open reduction internal fixation with combined locking plate and interfragmentary screws

PURPOSE

Fractures of the distal femur remain challenging to treat, and numerous fixation methods are designed to promote stability and fracture healing. Locking plate constructs have recently become the mainstream fixation method, but debate exists on whether to use locking plates alone or to augment them with interfragmentary screws. This article compares outcomes of distal femur fractures treated with a single locking plate alone versus those treated with a locking plate and interfragmentary screws.

METHODS

We retrospectively reviewed 57 patients treated for distal femur fractures from 2010 to 2013. Patients were divided into two groups: Those treated with a locking plate alone utilizing the minimally invasive plate osteosynthesis (MIPO) technique and those treated with combination of a locking plate and interfragmentary screws using an open technique. Postoperative outcomes were obtained via a manual chart review. Fracture healing and callus indices were evaluated from radiographs.

RESULTS

9 patients required revision surgery in the locking plate alone group (6 for persistent nonunion and 3 for varus deformity). Only two patients in the combination group required revisions (both for nonunion). Average time to full weight bearing was 19.54 weeks in the locking plate group versus 14.57 weeks in the combination group (p = 0.004). At the time of full weight bearing, frontal (1.15 versus 1.11, p = 0.004) and sagittal (1.22 versus 1.15, P = 0.008) callus indices were both significantly greater in the locking plate group.

CONCLUSIONS

In this study, the combination of a locking plate and interfragmentary screws achieved suitable stability and a faster time to full weight bearing than using a locking plate alone. Surgeons should consider combining a locking plate with interfragmentary screws as an effective method for fixation of distal femur fractures, particularly in cases when plate fixation alone fails to provide adequate fracture stability.

[Effect of low dose erythromycin on the proliferation of granulation tissue after tracheal injury]

Objective: To investigate the effect of low dose erythromycin on the proliferation of granulation tissue after tracheal injury. Methods: Forty-two rabbits were randomly divided into 7 groups (n=6 each), group A (saline control group), group B (penicillin group), group C (low dose erythromycin group), group D (low dose erythromycin and penicillin group), group E (budesonide group), group F (low dose erythromycin and budesonide group), group G (low dose erythromycin, penicillin and budesonide group). All rabbits received tracheotomy, and the tracheal mucosa was scraped with a nylon brush 20 times for tracheal stenosis model. Rabbits were treated with corresponding drugs from a week before operation to 9 days after operation. The serum concentrations of transforming growth factor - beta 1 (TGF-β(1)), vascular endothelial growth factor (VEGF), interleukin (IL) -6, IL-8 were determined and the tracheal specimens were harvested for measuring degree of stenosis on the 10th day after operation. Results: Serum concentrations of TGF-β(1) in group A, B, C, D, E, F and G were (17.6±1.3), (18.2±3.1), (13.0±1.1), (14.0±1.0), (21.0±6.1), (13.6± 3.5), (8.2±1.3) ng/L; VEGF were (88.1±4.1), (85.8±4.3), (58.1±6.3), (56.5±2.4), (87.8±2.8), (57.0±3.7), (34.3±6.7) ng/L; IL-6 were (67.8±4.0), (66.1±3.5), (54.1±4.8), (52.1±3.2), (64.6±4.9), (49.4±4.2), (35.9±3.7) ng/L; IL-8 were (112.8±5.2), (116.6±4.1), (88.0±6.2), (85.5±3.5), (114.4±4.6), (82.6±3.8), (55.9±6.0) ng/L, respectively. The serum concentrations of TGF-β(1), VEGF, IL-6 and IL-8 in group C, D, F and G were significantly lower than those in group A, B and E (all P<0.05). Compared with the other groups, the serum concentrations in group G were the lowest (all P<0.05). All 42 rabbits had tracheal stenosis with different degrees of proliferation of granulation tissue. The degree of tracheal stenosis in Group A, B, C, D, E, F and G were (53.3±4.4)%, (48.2±5.0)%, (24.3±4.4)%, (29.5±3.2)%, (47.8±6.5)%, (27.9±3.1)%, (15.6±2.0)%, respectively. The degree of tracheal stenosis in group C, D, F and G was significantly lower than that in group A, B and E, which had statistical differences (all P<0.05). Compared with the other groups, the degree of tracheal stenosis in group G was the lowest (all P<0.05). Conclusions: Low dose of erythromycin can effectively inhibit the proliferation of granulation tissue after tracheal injury in rabbits. And it has better effectiveness when combined with other antibiotics and hormone.

Duodenal Adenocarcinoma in a Patient with Partial Intestinal Malrotation

Background: Small bowel cancers, specifically duodenal cancer, occur at very low rates but require aggressive surgical resection when diagnosed. An even rarer finding is the presence of intestinal malrotation. Case Presentation: We present the unique case of a patient with both duodenal cancer and partial intestinal malrotation undergoing pancreaticoduodenectomy. We discuss the challenges faced and techniques used to successfully perform a surgical resection in this circumstance. Conclusion: Understanding of intestinal malrotation and review of the imaging is crucial in preparing for a resection of a duodenal tumor in a patient with this condition.

[Psychopathological characteristics in patients with deviation of nasal septum: a preliminary analysis]

Objective: To investigate the psychopathological characteristics in patients with deviation of nasal septum. Methods: Between May 2015 and December 2015, fourty-four patients with deviated nasal septum and 37 patients with vocal cord polyp as control were included in this study. Psychological characteristics were evaluated by a series of questionnaire instruments including symptom checklist-90 (SCL-90), self-rating depression scale (SDS) and self-rating anxiety scale (SAS). Visual analogue scale (VAS) and rhinomanometry through front nostril were used to evaluate nasal symptom. The correlation between psychological characteristics and nasal symptom was evaluated. SPSS 20.0 software was used to analyze the data. Results: The SCL-90 score in nasal septal deviation group was 130.4±48.3. The total score and total average score of SCL-90 had no significant difference between nasal septal deviation group and the Chinese standard or control group(t value was 0.469, 0.112, 1.575, 1.564, respectively, all P>0.05). The scores of somatization, depression and anxiety factors in nasal septal deviation group were higher than control group (t value was 2.380, 2.133, 1.969, respectively, all P<0.05). The proportion of positive patients in these three factors between nasal septal deviation group and control group had significant differences (χ² value was 11.585, 9.610, 5.429, respectively, all P<0.05). The scores of SDS and SAS in nasal septal deviation group were 46.0±10.6 and 43.0±10.2, which were higher than that in the Chinese standard and control group (t value was 5.342, 6.236, 1.476, 3.013, respectively, all P<0.05). There were 9 patients companying with depression or anxiety (20.5%, 20.5%, respectively) and 5 patients companying with depression and anxiety in nasal septal deviation group (11.4%). There were positive correlation not only between the scores of SDS and the depression factor of SCL-90 but also between the scores of SAS and the anxiety factor of SCL-90 (Z=0.415, P=0.005, Z=0.445, P=0.002, respectively). The scores of SDS and SAS had positive correlation (Z=0.392, P=0.008). The VAS score of nasal obstruction was 6.0±3.2. The rhinomanometry in inspiratory and expiratory phase were (0.202±0.140) kPa·S/cm³ and (0.230±0.161) kPa·S/cm³. Besides the positive correlation between the rhinomanometry in inspiratory phase and SDS (Z=0.332, P=0.045), the psychological scores, including SCL-90 score, depression, anxiety factors score, SAS and SDS, had no correlation with VAS scores and rhinomanometry (r value was -0.030, -0.052, -0.026, 0.107, 0.185, 0.066, 0.160, 0.203, respectively, all P>0.05). Conclusions: High prevalence of depression and anxiety is found in patients with deviation of nasal septum. The SCL-90 score is consistent with SDS and SAS. Besides the positive correlation between the rhinomanometry in inspiratory phase and SDS, the psychological scores (SCL-90 score, depression, anxiety factors score, SAS and SDS) have no correlation with VAS score and rhinomanometry.

[Progress in the study of central auditory processing disorders]

Summary With the development of artifical ossicular and cochlear implant，the treatment of refractory hearing loss acquire significant breakthrough，thus central auditory processing disorders are becoming the major cause of refractory hearing loss.In this paper，research progress of central auditory processing disorders in clinical and fundamental are reviewed.

[Characteristic and clinical significance of DNA methyltransferase 3B overexpression in endometrial carcinoma]

OBJECTIVE

To determine the clinicopathological significance of the DNA methyltransferase 3B (DNMT3B) overexpression in endometrial carcinomas and to evaluate its correlation with hormone receptor status.

METHODS

Immunohistochemistry was performed to assess the expression of DNMT3B and hormone receptors in 104 endometrial carcinomas.

RESULTS

DNMT3B overexpression occurred frequently in endometrioid carcinoma (EC, 54.8%) more than in nonendometrioid carcinoma (NEC, 30.0%) with statistical significance (P=0.028). Furthermore, there was a trend that EC with worse clinico-pathological variables and shorter survival had a higher DNMT3B expression, and the correlation between DNMT3B and tumor grade reached statistical significance (P=0.019).A negative correlation between DNMT3B and estrogen receptor (ER) or progesterone receptor (PR) expression was found in EC. NMT3B overexpression occurred frequently in the ER or PR negative subgroups (78.9%, 86.7%) more than in the positive subgroups (47.7%, 47.8%) with statistical significance (P=0.016, P=0.006). In addition, the DNMT3B overexpression increased in tumors with both ER and PR negative expression (92.9%, P=0.002). However, no such correlation was found in NEC (P>0.05). Sequence analyses demonstrated multiple ER and PR binding sites in the promoter regions of DNMT3B gene.

CONCLUSION

This study showed that the expression of DNMT3B in EC and NEC was different. DNMT3B overexpression in EC was associated with the worse clinicopathological variables and might have predictive value. The methylation status of EC and NEC maybe different. In addition, in EC, DNMT3B overexpression negatively correlated with ER or PR expression. In NEC, the correlation between DNMT3B and ER or PR status was not present.

High-Brightness High-Energy Electron Beams from a Laser Wakefield Accelerator via Energy Chirp Control

By designing a structured gas density profile between the dual-stage gas jets to manipulate electron seeding and energy chirp reversal for compressing the energy spread, we have experimentally produced high-brightness high-energy electron beams from a cascaded laser wakefield accelerator with peak energies in the range of 200-600 MeV, 0.4%-1.2% rms energy spread, 10-80 pC charge, and ∼0.2  mrad rms divergence. The maximum six-dimensional brightness B_{6D,n} is estimated as ∼6.5×10^{15}  A/m^{2}/0.1%, which is very close to the typical brightness of e beams from state-of-the-art linac drivers. These high-brightness high-energy e beams may lead to the realization of compact monoenergetic gamma-ray and intense coherent x-ray radiation sources.

Association between MTHFR gene polymorphisms (C677T, A1298C) and genetic susceptibility to prostate cancer: a meta-analysis

Genetic polymorphisms (C677T and A1298C) in methylenetetrahydrofolate reductase (MTHFR) were shown to be related to prostate cancer risk in previous studies; however, the results are controversial. We performed a meta-analysis of previous studies and quantitatively estimated these associations. Pubmed, Embase, and Cochrane Library Database were searched for published case-control studies evaluating the association between C677T (or A1298C) and prostate cancer risk. Pooled associations were presented as odds ratios (ORs) along with their 95% confidence intervals. Twenty-one case control studies were identified for meta-analysis that included 21,581 participants. No significant associations were found between the MTHFR polymorphisms C677T or A1298C and prostate cancer risk in our meta-analysis. However, in subgroup analyses, the C677T CT polymorphism was associated with increased prostate cancer risk in East Asians (CT vs CC+TT: OR = 1.324, P = 0.03). The A1298C CC polymorphism in MTHFR was also linked to slightly reduced prostate cancer risk in European residents (CC vs AC+AA: OR = 0.751, P = 0.004; CC vs AA: OR = 0.768, P = 0.011), whereas it was associated with a significantly increased prostate cancer risk in Asian residents (CC vs AA: OR = 1.862, P = 0.006). The C677T CT polymorphism of MTHFR may be a risk factor for prostate cancer in East Asians. The association between the MTHFR A1298C CC genotype and prostate cancer risk may vary within different populations. Large-scale well-designed studies are required to confirm these associations.

Vagal afferent-dependent cholecystokinin modulation of visceral pain requires central amygdala NMDA-NR2B receptors in rats

BACKGROUND

Cholecystokinin (CCK), a gut hormone that is released during feeding, exerts gastrointestinal effects in part through vagal pathway. It is reported to be a potential trigger for increased postprandial visceral sensitivity in healthy subjects and, especially in patients with irritable bowel syndrome. NR2B-containing N-methyl-d-aspartate (NMDA) receptors in the central amygdala (CeA) participate in pain modulation. Systemically administered CCK activates the CeA-innervating neurons. Here, we investigated whether CCK modulation of visceral sensitivity is mediated through CeA NMDA-NR2B receptors and whether this modulation involves vagal pathway.

METHODS

We first examined the visceromotor response (VMR) to colorectal distention (CRD) following i.p. injection of CCK octapeptide (CCK-8) in a rat model. Next, the NR2B antagonist ifenprodil and the NR2A antagonist NVP-AAM077 were microinjected into the CeA before systemic CCK injection. NR2B phosphorylation was detected by Western blot. To down-regulate NR2B gene expression, NR2B-specific small interfering RNA (siRNA) was delivered into CeA neurons by electroporation. In addition, the effects of functional deafferentation by perivagal application of capsaicin and pretreatment with the CCK1 receptor antagonist devazepide were investigated.

KEY RESULTS

CCK-8 increased VMR to CRD in a dose-dependent manner. This effect was blunted by intra-CeA administration of ifenprodil (but not NVP-AAM077) and was accompanied by phosphorylation of NR2B subunits in the CeA. CCK failed to increase VMR to CRD in NR2B siRNA-treated rats. Perivagal capsaicin application and pretreatment with devazepide prevented CCK-induced pronociception and CeA NR2B phosphorylation.

CONCLUSIONS & INFERENCES

The pronociception induced by systemic CCK, which is vagal afferent-dependent, requires activation of CeA NMDA-NR2B receptors.

Association of BCSC-1 with human esophageal squamous cell carcinoma

Breast cancer suppressor candidate-1 (BCSC-1) is a newly identified candidate tumor suppressor gene. BCSC-1 shows decreased levels in a variety of cancer types. In this study, we investigated the association between BCSC-1 and human esophageal squamous cell carcinoma (ESCC). BCSC-1 expression was detected in ESCC and normal tissues adjacent to tumor tissues by Western blot analysis and real-time PCR  as well as immunohistochemistry of paraffin sections. The relationships between BCSC-1 expression and various clinicopathological characteristics were analyzed. Western blot analysis and real-time PCR showed that levels of BCSC-1 protein and mRNA expression in ESCC significantly decreased compared with those in adjacent normal tissues.  Immunohistochemistry exhibited marked reduction of BCSC-1 in 38 of 105 ESCC specimens. Moreover, downregulation of BCSC-1 was associated with the grade of tumor cellular differentiation (P<0.05). These findings indicate that BCSC-1 downregulation in ESCC is associated with carcinogenesis and may play important roles during the process of ESCC cancer development.

Proteomic analysis identifies differentially expressed proteins participating in forming Type III brush hair in Yangtze River Delta white goat

The Yangtze River Delta white goat is a goat breed that can produce high quality brush hair (Type III hair) around the world. This study aimed to compare Type III hair and non-Type III hair goat skin tissues using differentially expressed proteins based on 2-dimensional gel electrophoresis technology. The differentially expressed protein spots were analyzed using the PDquest 8.0 software. Ten protein spots were detected as positive for mass spectrometric analysis based on a threshold of 2-fold change. Through matching based on Ultraflex III TOF/TOF and MASCOT database, four differentially expressed proteins were identified. Fibrinogen beta chain isoform 1 and ATP synthase beta subunit were upregulated in Type III hair, while succinyl-CoA:3-ketoacid-coenzyme A transferase 1-mitochondrial-like and actin-cytoplasmic 1 were upregulated in non-Type III hair. The 4 proteins play important roles in different aspects of hair follicle development. These findings could pave a good foundation for explaining the mechanism of forming Type III hair.

Downregulation of PLK1 by RNAi attenuates the tumorigenicity of esophageal squamous cell carcinoma cells via promoting apoptosis and inhibiting angiogenesis

Polo-like kinase 1(PLK1) is essential for the maintenance of genomic stability during mitosis. PLK1 has been reported to be upregulated in several solid tumors, including esophageal squamous cell carcinoma (ESCC). However, the role of PLK1 in tumorigenesis of ESCC remains undetermined. We used siRNA and lentivirus-mediated PLK1 RNA interference to investigate the tumor suppressor function of PLK1 reduction in ESCC cells. Flow cytometry and Terminal deoxynuleotidyl transferase-mediated nick-end labeling assay in vitro, as well as immunohistochemitry analysis of Caspase-3 and CD31 in s.c. tumor tissue section, were performed. Knock down of PLK1 expression significantly suppressed the ability of ESCC cells to form colonies in plastic and soft agar. PLK1 reduction mediated by lentivirus caused growth suppression of ESCC in nude mice. Caspase-3 upregulation further indicated that dysregulated apoptosis might contribute to reduced tumorigenecity. In particular, downregulation of CD31 suggested that PLK1 reduction-induced angiogenesis inhibition may also contribute, at least in part, to attenuated tumorigenecity. These findings indicate that PLK1 might play roles in tumorigenesis of ESCC and that PLK1 might be a potential gene therapy target in ESCC. Apoptosis induction together with decreased angiogenesis might be involved in the mechanism of tumor suppressor function of RNA interference targeting PLK1.

Long-term effects of evodiamine on expressions of lipogenesis and lipolysis genes in mouse adipose and liver tissues

Evodiamine, the major alkaloid component isolated from the fruit of dried, unripened Evodia rutaecarpa Bentham, affects the plasma levels of cholecystokinin and various biological events such as gastric emptying and gastrointestinal transit; these effects of evodiamine were previously investigated in male rats. In this study, we aimed to investigate the effects of evodiamine on average daily weight gain, rectal temperature, and expressions of genes involved in lipid metabolism in liver and adipose tissues. Evodiamine was added as a supplement, comprising 0.02, 0.04, and 0.06% of the diet fed to mice for 1, 2, 3, and 4 weeks. Results showed that average daily weight gain and rectal temperature decreased significantly over time in a dose-dependent manner. Evodiamine changed expressions of the peroxisome proliferator-activated receptor-g (PPARg) in mouse adipose and liver tissues in time- and dose-dependent manners. We found that evodiamine decreased mRNA expression of the sterol-regulatory element binding protein (SREBP-1c) and fatty acid synthase in adipose tissue. In addition, evodiamine increased expressions of hormone-sensitive lipase in both liver and adipose tissues. Interestingly, evodiamine increased the expression of triglyceride hydrolase only in adipose tissue. In conclusion, evodiamine could influence lipid metabolism through regulation of the expressions of its key genes, as well as reduce body heat and body weight.

PTEN hypermethylation profiles of Chinese Kazakh patients with esophageal squamous cell carcinoma

Aberrant DNA methylation of promoter region CpG islands may serve as an alternative mechanism to genetic defects in the inactivation of tumor suppressor genes (TSGs) in human malignancies. The aim of this study was to examine the promoter methylation status of the PTEN TSG and its association with esophageal squamous cell carcinoma (ESCC) carcinogenesis in a Chinese Kazakh population, which is known to have a relatively high ESCC incidence and mortality. The methylation status of the PTEN promoter region was determined in patients with ESCC (n = 95) and healthy individuals (n = 65) using highly sensitive Sequenom Epityper assays. The methylation level of the PTEN gene was significantly higher in patients with ESCC than in healthy controls. The median methylation level was 10.0% (interquartile range [IQR]: 7.0-11.0%) in patients with ESCC and 6.0% in controls (IQR: 4.0-9.0%; P = 0.001). PTEN methylation levels were higher in male patients with ESCC than in male controls, whereas a trend toward significance was observed between female patients with ESCC and female controls (P = 0.005 and P = 0.086, respectively). The PTEN methylation level was associated with histopathological grade and lymph node metastasis in patients with ESCC (P = 0.002 and P = 0.009, respectively). To our knowledge, this is the first report to show the presence of PTEN promoter CpG hypermethylation in ESCC and its association with tumor metastasis.

Preparation and characterization of an antiserum against truncated UL54 protein of pseudorabies virus

Pseudorabies virus (PRV) early protein UL54 is a homolog of herpes simplex virus 1 immediate-early protein ICP27, which is a multifunctional protein essential for the virus replication. However, the precise role of the PRV UL54 protein in the virus life cycle is still poorly understood. To shed more light on this problem, we considered it essential to have available an antiserum specifically detecting this protein. Since it was known that a full-length UL54 protein is a too big molecule for efficient expression in prokaryotic systems, it was truncated from 1 to 66 N-terminal amino acids, fused to EYFP-His tag and expressed in Escherichia coli through an appropriate expression vector. The truncated protein was purified by Ni-NTA affinity chromatography and used for raising an antiserum in rabbits. Western blot analysis showed that this antiserum specifically recognized the purified truncated as well as full-length UL54 protein in PRV-infected cells. Immunofluorescence assay confirmed the latter finding and also demonstrated localization of this protein first in nucleoli and later in whole nuclei of PRV-infected cells. These results indicate that the prepared antiserum could serve as a valuable tool in further studies of PRV UL54 protein function.

All-optical cascaded laser wakefield accelerator using ionization-induced injection

We report on near-GeV electron beam generation from an all-optical cascaded laser wakefield accelerator (LWFA). Electron injection and acceleration are successfully separated and controlled in different LWFA stages by employing two gas cells filled with a He/O2 mixture and pure He gas, respectively. Electrons with a Maxwellian spectrum, generated from the first LWFA assisted by ionization-induced injection, were seeded into the second LWFA with a 3-mm-thick gas cell and accelerated to be a 0.8-GeV quasimonoenergetic electron beam, corresponding to an acceleration gradient of 187  GV/m. The demonstrated scheme paves the way towards the multi-GeV laser accelerators.

Modulation of BCRP mediated atypical multidrug resistance phenotype by RNA interference

Multidrug resistance (MDR) in human cancers is one of the major causes of failure of chemotherapy. The emergence of breast cancer resistance protein (BCRP), a member of the ABC transporter family, has necessitated the development of antagonists. To overcome the BCRP-mediated atypical multidrug drug resistance, two small interfering RNA constructs (RNAi) targeting two different regions of BCRP mRNA were designed to inhibit the atypical MDR expression by transfecting them into MCF-7/MX100 cell lines. The multidrug resistance index to mitoxantrone and the intensity of mitoxantrone fluorescence of MCF-7/MX100 decreased after transfected by pSUPER-BCRP-A and pSUPER-BCRP-B respectively; the BCRP mRNA level and the BCRP protein level of MCF-7/MX100 decreased after treated with pSUPER-BCRPs. The two constructed RNAi plasmids could reverse the atypical mutidrug resistance mediated by BCRP, but neither can reversed it completely, this may be due to low transfection efficiency and transient transfection.

Mutational analysis of differences in thermostability between histones from mesophilic and hyperthermophilic archaea

Amino acid residues responsible for the large difference in thermostability between HMfB and HFoB, archaeal histones from the hyperthermophile Methanothermus fervidus and the mesophile Methanobacterium formicicum, respectively, have been identified by site-specific mutagenesis. The thermal denaturation of approximately 70 archaeal histone variants has been monitored by circular dichroism, and the data generated were fit to a two-state unfolding model (dimer-->two random coil monomers) to obtain a standard-state (1M) melting temperature for each variant dimer. The results of single-, double-, and triple-residue substitutions reveal that the much higher stability of rHMfB dimers, relative to rHFoB dimers, is conferred predominantly by improved intermolecular hydrophobic interactions near the center of the histone dimer core and by additional favorable ion pairs on the dimer surface.

MJ1647, an open reading frame in the genome of the hyperthermophile Methanococcus jannaschii, encodes a very thermostable archaeal histone with a C-terminal extension

All archaeal histones studied to date have similar lengths, 66 to 69 amino acid residues that form three alpha-helices separated by two beta-strand loop regions which together constitute a histone fold. In contrast, the eukaryal nucleosome core histones are larger, 102 to 135 residues in length, with N-terminal and C-terminal extensions flanking the histone fold that participate in gene regulation and higher-order chromatin assembly. In the Methanococcus jannaschii genome, MJ1647 was annotated as an open reading frame predicted to encode an archaeal histone with an approximately 27-amino-acid C-terminal extension, and we here document the DNA binding and assembly properties and thermodynamic stability parameters of the recombinant product of MJ1647 synthesized in Escherichia coli with (rMJ1647) and without (rMJ1647delta) the C-terminal extension. The presence of the C-terminal extension did not prevent homodimer formation or inhibit DNA binding, but the complexes formed by rMJ1647, presumably archaeal nucleosomes containing a (rMJ1647)4 tetramer, were apparently less stable than those formed by (rMJ1647delta)4. The presence of the C-terminal extension increased the thermostability of rMJ1647 when compared with rMJ1647delta in 0.2 M KCl at pH 4 but not in the absence of KCl at pH 1. Based on thermal unfolding transitions, rMJ1647 and rHAfB generated by expression of AF0337 cloned from the genome of the related hyperthermophile Archaeoglobus fulgidus in E. coli were found to have higher thermodynamic stabilities than all previously studied archaeal histones.

Thermodynamic stability of archaeal histones

The temperature, salt, and pH dependencies of unfolding of four recombinant (r) archaeal histones (rHFoB from the mesophile Methanobacterium formicicum, and rHMfA, rHMfB, and rHPyA1 from the hyperthermophiles Methanothermus fervidus and Pyrococcus strain GB-3a) have been determined by circular dichroism spectroscopy (CD) and differential scanning calorimetry (DSC). The thermal unfolding of these proteins is > 90% reversible, with concentration-dependent apparent Tm values and asymmetric unfolding transitions that are fit well by a two-state unfolding model in which a histone dimer unfolds to two random coil monomers. rHPyA1 dimers are stable in the absence of salt, whereas rHMfA, rHMfB, and rHFoB dimers unfold at 20 degrees C and pH 2 in solutions containing < 200 mM, < 400 mM, and < 1.5 M KCl, respectively. rHMfA, rHMfB, and rHFoB also experience significant cold denaturation in low salt concentrations and at low pH. The midpoint of thermal unfolding of a 1 M protein solution (T degree value) and the temperature dependency of the free energy of unfolding have been established for each histone, and both parameters correlate with the growth temperature of the originating archaeon. The changes in heat capacity upon unfolding are similar for the four histones, indicating that enhanced thermostability is not obtained by altering the curvature of the stability curve. Rather, the stability curves for the histones from the hyperthermophiles are displaced vertically to higher energies and laterally to higher Tmax values relative to the stability curve for rHFoB. The maximal free energies of unfolding for rHFoB, rHMfA, rHMfB, and rHPyA1 are 7.2, 15.5, 14.6, and 17.2 kcal/mol at 32, 35, 40, and 44 degrees C, respectively. T degree values for rHFoB, rHMfA, rHMfB, and rHPyA1 are 75, 104, 113, and 114 degrees C, respectively, at pH 5 in 0.2 M KCl. Structural features within the conserved histone fold that might confer these stability differences are discussed.

Archaeal histone stability, DNA binding, and transcription inhibition above 90 degrees C

The DNA binding and compacting activities of the recombinant (r) archaeal histones rHMfA and rHMfB from Methanothermus fervidus, and rHPyA1 from Pyrococcus species GB-3a, synthesized in Escherichia coli, have been shown to be completely resistant to incubation for 4h at 95 degrees C in the presence of 1M KCl. Continued incubation of rHMfA and rHMfB at 95 degrees C resulted in a gradual loss of these activities, and rHMfA and rHMfB lost activity more rapidly at 95 degrees C when the salt environment was reduced to 200 mM K Cl. rHPyA1, in contrast, retained full activity even after a 60-h incubation at 95 degrees C in 1 M KCl, and reducing the salt concentration did not affect the heat resistance of rHPyA1. rHPya1-DNA complexes remained intact at 100 degrees C, and rHPyA1 bound to the template DNA in in vitro transcription reaction mixtures assembled using Pyrococcus furiosus components at 90 degrees C. Transcription in vitro from the P. furiosus gdh promoter was reduced by rHPyA1 binding, in a manner that was dependent on the histone-to-DNA ratio and on the topology of the DNA template. Transcription from circular templates was more sensitive to rHPyA1 binding than transcription from a linear template, consistent with rHPyA1 binding introducing physical barriers to transcription and causing changes in the topology of circular templates that also reduced transcription.