Does prior failed shock-wave lithotripsy impact outcomes of ureterorenoscopy? A systematic review and meta-analysis

OBJECTIVE

The study aimed to compare the outcomes of patients undergoing ureterorenoscopy (URS) after failed shock-wave lithotripsy (SWL) (Salvage URS) with those undergoing URS without any history of SWL (Primary URS).

MATERIALS AND METHODS

PubMed, Embase, and CENTRAL databases were searched up to 10th January 2021 for studies comparing outcomes of salvage URS vs. primary URS. Odds ratios (OR) with 95% confidence intervals (CI) were calculated for procedure success and complications. Operating time was summarized using mean difference (MD).

RESULTS

Seven retrospective studies were included. Meta-analysis indicated no statistically significant difference in the success rates of URS between the salvage URS and primary URS groups (OR: 0.83 95% CI: 0.65, 1.06 I2=0% p=0.13). On subgroup analysis, the success rate was significantly reduced in the salvage URS group for renal stones (OR: 0.55 95% CI: 0.34, 0.91 I2=0% p=0.02) but with no difference for ureter stones OR: 0.90 95% CI: 0.67, 1.21 I2=0% p=0.49). Pooled analysis demonstrated a tendency of longer operating time in the salvage URS group as compared to the primary URS group, albeit with a statistically non-significant difference (MD: 8.91 95% CI: -0.56, 18.38 I2=98% p=0.07). Meta-analysis indicated significantly increased complications in the salvage URS group as compared to the primary URS group (OR: 1.83 95% CI: 1.34, 2.49 I2=0% p=0.0001).

CONCLUSIONS

Evidence from retrospective studies suggests that patients undergoing salvage URS for renal stones have significantly lower success rates which is not the case for ureteral stones. There is a non-significant tendency of increased operating times for salvage URS. Complication rates are significantly higher for salvage URS as compared to primary URS. Future studies with propensity-score matching are required to strengthen current conclusions.

[Establishment and application of a nomogram model for prognostic risk prediction in patients with epithelial ovarian cancer]

Objective: To explore the prognostic factors of epithelial ovarian carcinoma (EOC), construct a nomogram model, and evaluate the prognosis of EOC patients. Methods: A retrospective analysis was performed on clinicopathological data of 208 cases of EOC patients who received initial treatment in the First Affiliated Hospital of Army Medical University from August 11, 2016 to July 11, 2018, including age, preoperative ascites, preoperative neoadjuvant chemotherapy, surgical method, pathological type, pathological differentiation degree, surgical pathology stage, preoperative and post-chemotherapy serum cancer antigen 125 (CA₁₂₅) level, human epididymal protein 4 (HE4) level, platelet count and platelet/lymphocyte number ratio (PLR). The univariate and multivariate Cox risk ratio models were used to analyze the related factors affecting progression free survival (PFS) in EOC patients, and the prediction nomogram of PFS in EOC patients was established to evaluate its efficacy in predicting PFS. Results: Univariate analysis showed that preoperative neoadjuvant chemotherapy, pathological type, pathological differentiation degree, surgical pathology stage, serum CA₁₂₅ and HE4 level before operation and after chemotherapy, platelet count and PLR before operation and after chemotherapy were significantly correlated with PFS in EOC patients (all P<0.05). Multivariate analysis showed that surgical pathology stage, preoperative PLR, serum CA₁₂₅ and HE4 level after chemotherapy were independent prognostic factors affecting PFS of EOC patients (all P<0.01). The index coefficient of the prediction model for the prognosis of EOC patients established by this method was 0.749 (95% CI: 0.699-0.798), which had good prediction ability, and could help clinicians to more accurately evaluate the prognosis of EOC patients. Conclusion: The nomogram model constructed based on surgical pathology stage, preoperative PLR, serum CA₁₂₅ and HE4 level after chemotherapy could effectively predict the PFS of EOC patients after initial treatment, could help clinicians to screen high-risk patients, provide individualized treatment, and improve the prognosis of EOC patients.

A non-coding RNA balancing act: miR-346-induced DNA damage is limited by the long non-coding RNA NORAD in prostate cancer

BACKGROUND

miR-346 was identified as an activator of Androgen Receptor (AR) signalling that associates with DNA damage response (DDR)-linked transcripts in prostate cancer (PC). We sought to delineate the impact of miR-346 on DNA damage, and its potential as a therapeutic agent.

METHODS

RNA-IP, RNA-seq, RNA-ISH, DNA fibre assays, in vivo xenograft studies and bioinformatics approaches were used alongside a novel method for amplification-free, single nucleotide-resolution genome-wide mapping of DNA breaks (INDUCE-seq).

RESULTS

miR-346 induces rapid and extensive DNA damage in PC cells - the first report of microRNA-induced DNA damage. Mechanistically, this is achieved through transcriptional hyperactivation, R-loop formation and replication stress, leading to checkpoint activation and cell cycle arrest. miR-346 also interacts with genome-protective lncRNA NORAD to disrupt its interaction with PUM2, leading to PUM2 stabilisation and its increased turnover of DNA damage response (DDR) transcripts. Confirming clinical relevance, NORAD expression and activity strongly correlate with poor PC clinical outcomes and increased DDR in biopsy RNA-seq studies. In contrast, miR-346 is associated with improved PC survival. INDUCE-seq reveals that miR-346-induced DSBs occur preferentially at binding sites of the most highly-transcriptionally active transcription factors in PC cells, including c-Myc, FOXA1, HOXB13, NKX3.1, and importantly, AR, resulting in target transcript downregulation. Further, RNA-seq reveals widespread miR-346 and shNORAD dysregulation of DNA damage, replication and cell cycle processes. NORAD drives target-directed miR decay (TDMD) of miR-346 as a novel genome protection mechanism: NORAD silencing increases mature miR-346 levels by several thousand-fold, and WT but not TDMD-mutant NORAD rescues miR-346-induced DNA damage. Importantly, miR-346 sensitises PC cells to DNA-damaging drugs including PARP inhibitor and chemotherapy, and induces tumour regression as a monotherapy in vivo, indicating that targeting miR-346:NORAD balance is a valid therapeutic strategy.

CONCLUSIONS

A balancing act between miR-346 and NORAD regulates DNA damage and repair in PC. miR-346 may be particularly effective as a therapeutic in the context of decreased NORAD observed in advanced PC, and in transcriptionally-hyperactive cancer cells.

Association between the Lymphocyte-to-C-Reactive Protein Ratio and Survival Outcomes in Cancer Patients with GLIM-Defined Malnutrition: A Multicenter Study

BACKGROUND AND AIMS

This study assessed the prognostic value of LCR in patients with cancer-associated malnutrition (CAM). Systemic inflammatory markers, particularly the lymphocyte-to-C-reactive protein ratio (LCR), are related to the survival of patients with CAM. The present retrospective analysis based on a prospective multicenter cohort study, which involved 1,437 hospitalized patients with CAM.

METHODS

The area under the receiver operating characteristic curve (AUC) of ten inflammatory indicators-LCR, advanced lung cancer inflammation index, neutrophil-to-lymphocyte ratio, prognostic nutritional index, modified Glasgow prognostic score, systemic immune-inflammation index, albumin-to-globulin ratio, LCR score, glucose-to-lymphocyte ratio, and platelet-to-lymphocyte ratio-were constructed. Nutritional status, blood markers, and quality of life (QoL) were evaluated within 48 h of admission. The overall survival (OS) was evaluated from September 1 to December 29, 2021.

RESULTS

A total of 1,431 cancer patients diagnosed with malnutrition based on the Global Leadership Initiative on Malnutrition (GLIM) criteria. Male patients were 62.8% of all, and the mean age was 60.66 years old. The AUC of LCR was higher than that of other inflammatory markers. The restricted cubic spline (RCS) of the Hazard ratios (HRs) showed an inverse L-shaped relationship with LCR. In addition, patients with low LCR had significantly poorer OS than those with high LCR. The addition of LCR to the model increased the predictive ability of 1-year mortality (AUC increase of 0.036), 3-year mortality (AUC increase of 0.038), and 5-year mortality (AUC increase of 0.031).

CONCLUSIONS

Assessing the LCR can help the medical staff identify cancer patients with nutritional deficiency at high risk of oncological outcomes and develop individualized therapeutic strategies.

Synthesis of poly (2,6-diaminopyridine) using a rotating packed bed toward efficient production of polypyrrole-derived electrocatalysts

Synthesis of pyridinic-rich polymer is a key step in obtaining high-performance polypyrrole-derived electrocatalysts for oxygen reduction reaction. A straightforward and controllable synthesis method is highly favored to efficiently manupulate the...

P–412 Low serum hCG levels adjusted for the hCG trigger dose in fresh cycles may be associated with a poor clinical pregnancy rate of FET cycles

Study question

Is there any association between serum human chorionic gonadotropin (hCG) levels after trigger at previous fresh cycles and pregnancy outcomes of frozen-thawed embryo transfer (FET) cycles?

Summary answer

Low adjusted serum hCG level after hCG trigger at fresh cycles is negatively associated with clinical pregnancy rates (CPR) of hormone replacement treatment-FET (HRT-FET). What is known already: Literature showed that low serum hCG levels after the same dose of hCG trigger was associated with reduced pregnancy outcomes of the fresh cycles. However, the relationship between hCG levels after trigger at fresh cycles and pregnancy outcomes of FET cycles remains unknown.

Study design, size, duration

This matched retrospective study was conducted at a Reproductive Medicine Center between 2016 and 2018. Subjects performing HRT-FET cycles, whose previous fresh cycles used a bolus of hCG alone or a bolus of GnRHa combined with hCG for trigger were included. A total of 186 HRT-FET cycles with complete data was included for the final analysis.

Participants/materials, setting, methods

The study population was grouped into women with intramuscular injection of hCG prior to secretory transformation (hCG group, n = 93) and a comparison group (control group, n = 93) of women without hCG addition matched for patients’ age and duration of infertility. At the previous fresh cycles, serum hCG levels were measured 12 hours later after hCG trigger (defined as the “hCG+12 h” timepoint), and were adjusted for doses (defined as adjusted hCG levels). Main results and the role of chance: For patients achieving clinical pregnancy, the adjusted hCG level significantly increased (P &lt; 0.05). Meanwhile, the ROC curve also showed a significantly predictive value of adjusted serum hCG levels at the “hCG+12 h” timepoint for CPR in HRT- FET cycles (AUC=0.626, 95%CI: 0.512–0.740) and the optimal hCG threshold proposed by ROC for CPR was 46.31 mIU/mL with sensitivity of 71.4% and specificity of 56.9%. For all patients, the CPR in hCG group was significantly higher than that in control group (61.3% vs. 44.1%). Furthermore, all cycles were then divided into four groups based on the injection of hCG prior to secretory transformation in HRT-FET cycles and this cut-off value of hCG levels at the “hCG+12 h” timepoint. For patients with adjusted hCG levels ≤46.31 mIU/mL, the CPR was significantly improved in hCG group compared with control group (61.1% vs. 29.3%). But for patients with adjusted hCG levels &gt;46.31 mIU/mL, no statistically significant difference was observed between the hCG and control group (61.4% vs. 55.8%).

Limitations, reasons for caution

Although the results achieved statistically significant, the sample size was relatively small, which limits our ability to draw a definitive conclusion. The reason of the small sample size may be that to reduce the risk of OHSS, doctors would give preference to trigger with GnRH agonist in our center.

Wider implications of the findings: Adjusted serum hCG levels might represent a potential factor to guide adequate support in the subsequent HRT-FET cycles. Meanwhile, for patients with low adjusted serum hCG levels, intramuscular hCG injection prior to secretory transformation may be a good compensation way to rescue pregnancy impair in the subsequent HRT-FET cycles.

Trial registration number

N/A.

Numerical Simulation Study on the Mechanism of Formation of Apical Aneurysm in Hypertrophic Cardiomyopathy With Midventricular Obstruction

Apical aneurysm was observed to be associated with midventricular obstruction (MVO) in hypertrophic cardiomyopathy (HCM). To investigate the genesis of the apical aneurysm, the idealized numerical left ventricular models (finite-element left ventricle models) of the healthy left ventricle, subaortic obstruction, and midventricular obstruction in HCM of left ventricle were created. The mechanical effects in the formation of apical aneurysm were determined by comparing the myofiber stress on the apical wall between these three models (healthy, subaortic obstruction, and midventricular obstruction models). In comparing the subaortic obstruction model and MVO model with HCM, it was found that, at the time of maximum pressure, the maximum value of myofiber stress in MVO model was 75.0% higher than that in the subaortic obstruction model (654.5 kPa vs. 373.9 kPa). The maximum stress on the apex of LV increased 79.9, 69.3, 117.8% than that on the myocardium around the apex in healthy model, subaortic obstruction model, and MVO model, respectively. Our results indicated that high myofiber stress on the apical wall might initiate the formation process of the apical aneurysm.

Bone marrow-derived mesenchymal stem cells inhibit CD8+ T cell immune responses via PD-1/PD-L1 pathway in multiple myeloma

High expression of the inhibitory receptor programmed cell death ligand 1 (PD-L1) on tumor cells and tumor stromal cells have been found to play a key role in tumor immune evasion in several human malignancies. However, the expression of PD-L1 on bone marrow mesenchymal stem cells (BMSCs) and whether the programmed cell death 1 (PD-1)/PD-L1 signal pathway is involved in the BMSCs versus T cell immune response in multiple myeloma (MM) remains poorly defined. In this study, we explored the expression of PD-L1 on BMSCs from newly diagnosed MM (NDMM) patients and the role of PD-1/PD-L1 pathway in BMSC-mediated regulation of CD8⁺ T cells. The data showed that the expression of PD-L1 on BMSCs in NDMM patients was significantly increased compared to that in normal controls (NC) (18·81 ± 1·61 versus 2·78± 0·70%; P < 0·001). Furthermore, the PD-1 expression on CD8⁺ T cells with NDMM patients was significantly higher than that in normal controls (43·22 ± 2·98 versus 20·71 ± 1·08%; P < 0·001). However, there was no significant difference in PD-1 expression of CD4⁺ T cells and natural killer (NK) cells between the NDMM and NC groups. Additionally, the co-culture assays revealed that BMSCs significantly suppressed CD8⁺ T cell function. However, the PD-L1 inhibitor effectively reversed BMSC-mediated suppression in CD8⁺ T cells. We also found that the combination of PD-L1 inhibitor and pomalidomide can further enhance the killing effect of CD8⁺ T cells on MM cells. In summary, our findings demonstrated that BMSCs in patients with MM may induce apoptosis of CD8⁺ T cells through the PD-1/PD-L1 axis and inhibit the release of perforin and granzyme B from CD8⁺ T cells to promote the immune escape of MM.

Lurasidone in adolescents with schizophrenia: Sustained remission and recovery during 2 years of open-label treatment

Introduction

Compared with adult onset, early onset schizophrenia is typically characterized by greater illness severity and less favorable prognosis.

Objectives

To evaluate the proportion of adolescent patients with schizophrenia who achieved sustained remission and recovery during 2 years of treatment with lurasidone.

Methods

Patients aged 13-17 years with a DSM-IV-TR diagnosis of schizophrenia, and a Positive and Negative Symptom Scale (PANSS) total score ≥70 and <120, were randomized to 6 weeks of double-blind (DB), fixed-dose treatment with lurasidone (37 or 74 mg/d) or placebo. Patients who completed 6 weeks of DB treatment were eligible to enroll in a 2-year, open-label (OL), flexible dose extension study of lurasidone (18.5-74 mg/d). Criteria for sustained remission, were the 6-month consensus criteria summarized by Andreasen (Am J Psych 2005;162:441-9). Criteria for sustained recovery consisted of meeting sustained remission criteria with a Children’s Global Assessment Scale (CGAS) score ≥70 for at least 6-months indicating no clinically significant functional impairment.

Results

A total of 271 patients completed the 6-week DB study and entered the extension study, and 186 (68.6%) and 156 (57.6%) completed 52 weeks and 104 weeks of treatment, respectively. During OL treatment with lurasidone, 52.8% met sustained remission criteria, with a Kaplan-Meier (KM) estimate of 64.1 weeks for median time to sustained remission; and 28.8% met sustained recovery criteria, KM estimate of 104.6 weeks for median time to sustained recovery.

Conclusions

For adolescents with schizophrenia, treatment with lurasidone was associated with high rates of sustained remission and sustained recovery over a two-year period.

Disclosure

Employee of Sunovion Pharmaceuticals Inc. The study summarized in this Abstract was supported by funding from Sunovion Pharmaceuticals Inc

Relationship between epidermal growth factor receptor mutations and CT features in patients with lung adenocarcinoma

AIM

The purpose of this study was to investigate the relationship between epidermal growth factor receptor (EGFR) mutation status and computed tomography (CT) features in patients with lung adenocarcinoma.

MATERIALS AND METHODS

A total of 483 patients with lung adenocarcinoma diagnosed between January 2015 and April 2020 were included in this study. All patients underwent a preoperative chest CT, and a total of 31 detailed CT features were quantified. The mutation status of EGFR exon 18-21 was detected by a polymerase chain reaction (PCR)-based amplified refractory mutation system. Student's t and Fisher's exact or chi-square tests were used to compare continuous and categorical variables, respectively. Least absolute shrinkage and selection operator (LASSO) regularisation was used to determine the optimal combination of CT features and clinical characteristics to predict the EGFR mutation status. The model was tested using a validation set consisting of 120 patients.

RESULTS

EGFR mutations were found in 249 (51.6%) of 483 patients with lung adenocarcinoma. Univariate analysis showed that 14 CT features and two clinical characteristics correlated significantly with the EGFR mutation status. Smoking history, long-axis diameter, bubble-like lucency, pleural retraction, thickened bronchovascular bundles, and peripheral emphysema were independent predictors of the EGFR mutation status, according to LASSO regularisation. In the training and verification cohorts, the areas under the curve of the prediction model were 0.766 and 0.745, respectively.

CONCLUSIONS

CT features of patients with lung adenocarcinoma can help predict the EGFR mutation status.

Influence of operator volume on early outcomes of septal myectomy for isolated hypertrophic obstructive cardiomyopathy

Background

Guidelines on the diagnosis and management of hypertrophic cardiomyopathy (HCM) recommend that septal myectomy be performed by experienced operators. However, the impact of operator volume on surgical treatment outcomes for isolated HCM has been poorly investigated.

Methods

From 2002 to 2014, 435 consecutive patients with isolated HCM undergoing myectomy at the Fuwai Hospital were retrospectively enrolled. All 29 surgeons were divided into beginner surgeons (operator volume ≤20) and experienced surgeons (operator volume >20) according to the guidelines for the diagnosis and treatment of HCM. Propensity score matching of patients in the two groups was performed.

Results

Baseline differences included advanced New York Heart Association classification and older age in the experienced surgeon group. After matching, in the beginner surgeon group (107 cases), residual obstruction (18.7% vs. 0.9%, P<0.001) was more common, and the postoperative left ventricular outflow tract pressure gradient (20.7±15.1 vs. 14.3±7.4 mmHg, P<0.001) was higher than that of the experienced surgeon group. In the experienced surgeon group (107 cases), the incidence of mitral valve replacement (1.9% vs. 11.2%, P<0.001) and permanent pacemaker implantation (1.9% vs. 3.7%, P<0.001) was significantly lower than that in the beginner surgeon group. However, there was no difference in procedural mortality (1.9% vs. 1.9%) between the two groups.

Conclusions

Operator volume is an important factor in achieving better obstruction obliteration after septal myectomy in patients with isolated HCM.

Surgical treatment of pulmonary artery sarcoma: a report of 17 cases

Pulmonary artery sarcoma (PAS) is a rare and devastating disease. The diagnosis is often delayed, and optimal treatment remains unclear. The aim of this study is to report our experience in the surgical management of this disease. Between 2000 and 2018, 17 patients underwent operations for PAS at our center. The medical records were retrospectively reviewed to evaluate the clinical characteristics, operative findings, the postoperative outcomes, and the long-term results. The mean age at operation was 46.0 ± 12.4 years (range, 26–79 years), and eight (47.1%) patients were male. Six patients underwent tumor resection alone, whereas the other 11 patients received pulmonary endarterectomy (PEA). There were two perioperative deaths. Follow-up was completed for all patients with a mean duration of 23.5 ± 17.6 months (1–52 months). For all 17 patients, the median postoperative survival was 36 months, and estimated cumulative survival rates at 1, 2, 3, and 4 years were 60.0%, 51.4%, 42.9%, and 21.4%, respectively. The mean survival was 37.0 months after PEA and 14.6 months after tumor resection only (p = 0.046). Patients who had no pulmonary hypertension (PH) postoperatively were associated with improved median survival (48 vs. 5 months, p = 0.023). In conclusion, PAS is often mistaken for chronic pulmonary thromboembolism. The prognosis of this very infrequent disease remains poor. Early detection is essential for prompt and best surgical approach, superior to tumor resection alone, and PEA surgery with PH relieved can provide better chance of survival.

Comparisons of simulation results between passive and active fluid structure interaction models for left ventricle in hypertrophic obstructive cardiomyopathy

BACKGROUND

Patient-specific active fluid-structure interactions (FSI) model is a useful approach to non-invasively investigate the hemodynamics in the heart. However, it takes a lot of effort to obtain the proper external force boundary conditions for active models, which heavily restrained the time-sensitive clinical applications of active computational models.

METHODS

The simulation results of 12 passive FSI models based on 6 patients' pre-operative and post-operative CT images were compared with corresponding active models to investigate the differences in hemodynamics and cardiac mechanics between these models.

RESULTS

In comparing the passive and active models, it was found that there was no significant difference in pressure difference and shear stress on mitral valve leaflet (MVL) at the pre-SAM time point, but a significant difference was found in wall stress on the inner boundary of left ventricle (endocardium). It was also found that pressure difference on the coapted MVL and the shear stress on MVL were significantly decreased after successful surgery in both active and passive models.

CONCLUSION

Our results suggested that the passive models may provide good approximated hemodynamic results at 5% RR interval, which is crucial for analyzing the initiation of systolic anterior motion (SAM). Comparing to active models, the passive models decrease the complexity of the modeling construction and the difficulty of convergence significantly. These findings suggest that, with proper boundary conditions and sufficient clinical data, the passive computational model may be a good substitution model for the active model to perform hemodynamic analysis of the initiation of SAM.

[Study on the state of macrophage infiltration in the progression of non-alcoholic fatty liver disease induced by high-fat diet in mice]

Objective: Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease. Macrophages are an important cell-mediated immune response in the pathogenesis of NAFLD. However, the dynamic changes of intrahepatic infiltration during the pathogenesis of NAFLD remains unclear. Therefore, this study intends to investigate the changes and their correlations with morphological indicators, hepatic histopathological index, and intrahepatic macrophage infiltration in the progression of NAFLD induced by high-fat diet in mice. Methods: C57BL/6J mice were fed with 42% high-fat diet, and the morphological data and liver tissue were obtained at 1, 2, 4, 8 and 12 months, respectively. Hepatic histopathological characteristics were evaluated by HE stain. Immunohistochemical staining was used to detect the number of F4/80 positive cells in liver tissue at different stages to evaluate the degree of intrahepatic macrophage infiltration. Results: (1) The body weight, liver weight, and liver weight/body weight of mice fed with high-fat diet had gradually increased. (2) HE staining results showed that mice fed with high-fat diet had mainly developed simple steatosis within 1 to 2 months. In addition, a balloon-like hepatocyte degeneration and intralobular inflammation had begun to appear at 4 months, indicating that non-alcoholic steatohepatitis had started, and can be seen very clearly at 8 to 12 months. (3) Immunohistochemical staining results suggested that in the simple steatosis stage of NAFLD, the intrahepatic macrophage infiltration was not significant. However, after NAFLD activity score > 3, a large amount of infiltration had appeared and cluster-like changes in the later stage. (4) Correlation analysis results indicated that the degree of macrophage infiltration was not related to the mice morphological indicators (body weight, liver weight and liver weight/body weight) and pathological indicators (percentage of hepatic steatotic change, and degree of hepatocyte ballooning and intralobular inflammation), but was significantly related to the NAFLD activity score. Conclusion: High-fat diet can successfully induce NAFLD in mice and progress to the stage of non-alcoholic steatohepatitis. At the same time, high-fat diet can induce macrophage infiltration in liver tissue of mice and the changing trend of infiltration is related to NAFLD activity score.

Ultrafine- and uniform-grained biodegradable Zn-0.5Mn alloy: Grain refinement mechanism, corrosion behavior, and biocompatibility in vivo

An ultrafine- and uniform-grained Zn-0.5Mn alloy (D3 alloy, stands for deformation rate of 99.5%) is fabricated via multi-pass drawing. The alloy features excellent ductility and elongation properties (up to 245.0% ± 9.0% at room temperature). Zn-0.5Mn alloys are composed of two phases, namely, Zn and MnZn₁₃. The MnZn₁₃ phase confers multiple effects during refinement by inducing and pinning low-angle boundaries within grains. Meanwhile, the presence of these phases along grain boundaries prevents the growth of new refined grains. D3 shows uniform corrosion behaviors in c-SBF solution on account of the even distribution of the MnZn₁₃ phase in its microstructure. Animal implantation experiments indicate that D3 has good biocompatibility; it does not cause damage to bone tissue or other organs. Taking the results together, D3 may be developed into a new type of biodegradable material with remarkable elongation and corrosion properties and satisfactory biocompatibility for medical applications.