Corrigendum: Radiosynthesis and in-vitro identification of a molecular probe 131I-FAPI targeting cancer-associated fibroblasts.

[This corrects the article DOI: 10.3389/fonc.2024.1442601.].

Radiosynthesis and in-vitro identification of a molecular probe 131I-FAPI targeting cancer-associated fibroblasts.

Purpose: Fibroblast activation protein (FAP) is highly expressed in the mesenchyme of most malignant epithelial tumors, while its expression is low in normal tissues. FAP inhibitors (FAPIs) bind specifically to FAP and are used for tumor-targeted diagnosis and therapy. The aim of this study was to radiosynthesize a novel molecular probe 131I-FAPI and evaluate its in-vitro targeting and biological characteristics. Methods: The structurally modified FAPI was labelled with 131I through the chloramine-T method. The radiolabeling rate was then detected by thin-layer chromatography (TLC). The stability of 131I-FAPI was determined at PBS (room temperature) and serum (37°C). Its hydrophilicity was calculated by measuring its lipid-water partition coefficient. Pancreatic cancer PANC-1 cell line and glioma U87 cell line were cultured in vitro. Cell uptake assay was used to show the binding ability of 131I-FAPI. The CCK-8 assay was used to calculate the inhibitory effects of 131I-FAPI at different time points (4h, 8h, 12h, 24h, 48h) after comparing with the 131I and FAPI. The before-and-after-24h scratch areas of the two cells were determined in order to verify the effect of 131I-FAPI on the migration ability of the cells. Results: The radiolabeling rate was (84.9 ± 1.02) %. The radiochemical purity of 131I-FAPI remained over 80% in both 25°C PBS and 37°C serum. The value of the lipid-water partition coefficient was -0.869 ± 0.025, indicating the hydrophilic of the probe. The cellular uptake assay showed that U87 cells had a specific binding capacity for 131I-FAPI. In cell inhibition assays, the inhibitory effect of 131I-FAPI on U87 cells increased with time. The results of cell scratch assay showed that 131I-FAPI had the strongest inhibitory effect on the migratory ability of U87 cells compared with 131I and FAPI (P<0.001). Conclusion: 131I-FAPI was synthesized with good in-vitro stability and hydrophilic properties. It can be specifically bound by U87 cells. The proliferation and migration of U87 cells can be effectively inhibited. 131I-FAPI is promising to become a therapeutic probe.

Synergistic effects of Co-pyrolysis on the immobilization and transformation of lead (Pb), chromium (Cr), nickel (Ni), and fluorine (F) in phosphogypsum-biomass mixtures.

Co-pyrolysis of biomass with phosphogypsum (PG) presents an effective strategy for facilitating the recycling of PG resources. However, it is crucial to note the environmental threats arising from the presence of Pb, Cr, Ni, and F in PG. This study investigated the effect of immobilization and transformation of four elements during co-pyrolysis with biomass and its components. The co-pyrolysis experiments were carried out in a tube furnace with a mixture of PG and corn stover (CS), cellulose (C), lignin (L), glucose (G). Co-pyrolysis occurred at varying temperatures (600 °C, 700 °C, 800 °C, and 900 °C) and different addition ratios (10%, 15%, and 20%). The results indicated that an increase in co-pyrolysis temperature was more conducive to the immobilization and transformation of harmful elements in PG, demonstrating significant efficacy in controlling F. Additionally, the addition of biomass components exerts a significant impact on inhibiting product toxicity, with small molecules such as glucose playing a prominent role in this process. The mechanism underlying the control of harmful elements during co-pyrolysis of PG and biomass was characterized by three main aspects. Firstly, biomass components have the potential to melt-encapsulate the harmful elements in PG, leading to precipitation. Secondly, the pyrolysis gas produced during the co-pyrolysis process contributes to the formation of a rich pore structure in the product. Finally, this process aids in transforming hazardous substances into less harmful forms and stabilizing these elements. The findings of this study are instrumental in optimizing the biomass and PG blend to mitigate the environmental impact of their co-pyrolysis products.

Can99mTc-MDP-SPECT/CT Differentiate Loosening and Infection After Hip and Knee Replacements?

Background: Prosthetic loosening and infection are still common complications after joint replacement. Over the past few years, single-photon emission computed tomography-computed tomography (SPECT/CT) was widely used and showed unique value based on the combination of anatomic and metabolic information of foci. However, its performance in differentiating between prosthetic loosening and periprosthetic infection after joint replacement is still the focus of clinicians and deserves further investigation. Purpose: This retrospective study was aimed to determine whether bone scintigraphy combined with SPECT/CT still can differentiate prosthetic infection from loosening in patients after joint replacement. The differential efficacy in hip and knee prosthesis was also analyzed. Blood biomarkers for the diagnosis of periprosthetic infection were also evaluated. Patients and methods: Data sets of 74 prosthetic joints (including knees and hips), with suspected prosthetic loosening or infection between 2015 and 2021, were evaluated. Besides the results of nuclear imaging, X-ray images and serum biomarker were also recorded. Telephone follow-up and revision surgery after SPECT/CT were used as a gold standard. The sensitivity and accuracy of different imaging modalities were calculated by Chi-square test. The diagnostic efficacy of imaging methods and serum biomarkers were then analyzed by the area under curve (receiver operating characteristic curves, ROC) in SPSS 26. Results: In all, 47 joints (14 knees and 33 hips) were confirmed as aseptic loosening, while 25 joints (18 knees and 7 hips) were confirmed as infection. The sensitivity and accuracy of SPECT combined with SPECT/CT imaging were the highest (92.86% and 87.84%, respectively). The differential efficacy of bone scintigraphy combined with SPECT/CT imaging was also better than any other single imaging modality. In the analysis of involved prosthesis, prosthetic loosening occurred more in hip prosthesis and knee prosthesis was easily infected (P < 0.05). Finally, the sensitivity of ESR and CRP were 80% and 84%, respectively. Conclusions: Bone scintigraphy with hybrid SPECT/CT remains encouraging in differentiating prosthetic infection from loosening after joint replacement. The diagnostic efficacy of differentiation in hip prosthesis was better than knee. Serum biomarkers cannot be used alone to differentiate prosthetic infection from loosening.

A case of peritoneal Burkitt's lymphoma mimic of peritoneal tuberculosis.

Peritoneal lymphomatosis is a rare presentation of lymphoma that can mimic peritoneal tuberculosis. The computed tomography findings in both conditions include omental caking, thickening, and nodularity. We report the case of a 41-year-old man who presented with intermittent abdominal pain and distension. Abdominal CT initially suggested peritoneal tuberculosis due to the thickening of the peritoneum and greater omentum with multiple nodules. However, 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) images showed diffuse metabolic activity increase in the thickened peritoneum, omentum, and mesentery. An omental biopsy was performed under ultrasonography guidance, and histopathological examination revealed a high-grade Burkitt lymphoma. It is crucial to distinguish peritoneal lymphomatosis from tuberculosis, as the prognosis and management of the two conditions are vastly different.

A novel molecular imaging probe [99mTc]Tc-HYNIC-FAPI targeting cancer-associated fibroblasts.

Fibroblast activation protein (FAP) is higher expressed on cancer-associated fibroblasts (CAFs) in most malignant epithelial neoplasms, which is lower expressed in normal tissues. As a promising small molecular probe, FAP inhibitor (FAPI) shows the specific binding to FAP. This study aimed to explore a novel molecular probe [99mTc]Tc-HYNIC-FAPI targeting CAFs. The in vitro characteristics of the probe were also evaluated. The FAPI targeting FAP was designed, synthesized and conjugated with the chelator 6-hydrazinylnicotinic acid (HYNIC) for radiolabeling with 99mTc. The radiolabeling yield, radiochemical purity and stability were evaluated by Instant thin-layer chromatography (ITLC) and High performance liquid chromatography (HPLC). Lipophilicity was performed by the distribution coefficient test. The binding and migration ability of the probe was assessed using the FAP transfected tumor cell line. The radiolabeling yield of [99mTc]Tc-HYNIC-FAPI was (97.29 ± 0.46) %. The radiochemical purity was more than 90% and kept stable until 6 h. The radioligand was shown as lower lipophilicity, of which logD7.4 value was - 2.38 [Formula: see text] 0.13. In vitro experiments, the results indicated that the probe showed binding properties, and inhibited the migration of tumor cells. The novel [99mTc]Tc-HYNIC-FAPI probe was successfully radiosynthesized and exhibited good radiochemical purity, stability and in vitro binding ability to tumor cells. The [99mTc]Tc-HYNIC-FAPI will be a promising SPECT/CT imaging probe.

A systematic analysis of and recommendations for public health events involving brucellosis from 2006 to 2019 in China.

Brucellosis is a severe public health problem in China. However, analysis on related infection events is lacking. We performed a systematic analysis of brucellosis laboratory infection and vaccine infection events from 2006 to 2019 in China based on the published literatures. Our analysis showed that most laboratoryBrucellainfections in hospitals were found in Southern China. The identification and handling of suspected samples ofBrucellainfection without following the recommended biosafety protection was the main risk factor. It is important to strengthen the preventive awareness of clinical laboratory staff and physicians, while highlighting the compulsory handling and identification of suspectedBrucella-infected samples in biosafety facilities and following biosafety practices. However, a severe Brucella infection accident at the Northeast Agricultural University, with 28 positive cases, showed that strengthening the management in teaching experiments of students in the veterinary-related profession is essential. However, cluster S2 vaccine strain infection events caused by vaccination and production were mainly observed in Northern China. Strengthening vaccination skills, personal protection, and improving the biosafety management of vaccine production and implementing regular risk surveillance is mandatory. Our analysis provides helpful clues for control of public health events involving brucellosis, as well as implementing intervention strategies is urgent.

The effect of Huashibaidu formula on the blood oxygen saturation status of severe COVID-19: A retrospective cohort study.

BACKGROUND: Huashibaidu Formula (HSBD) for the COVID-19 treatment has been supported by the China's Diagnosis and Treatment Protocol for Novel Coronavirus Pneumonia. However, it is not clear whether HSBD can improve blood oxygen saturation and when it should be used with conventional therapies. PURPOSE: To access the effect of HSBD combined with conventional treatment on blood oxygen saturation of COVID-19 patients. METHODS: A single-center retrospective cohort study was conducted to collect the confirmed severe COVID-19 patients' information, treated by the National Traditional Chinese Medicine Medical Team at the Jinyintan hospital between January 24 and March 31, 2020. According to whether HSBD was used during hospitalization, participants were separated into the conventional treatment group and the HSBD group (HSBD and conventional treatment). The primary observation indicators included the time for relieving blood oxygen saturation and the improvement ratio of blood oxygen saturation in each group. RESULTS: Of 111 patients with severe COVID-19, 53.2% (59/111) received HSBD, and 46.8% (52/111) only received conventional treatment, respectively. No statistically significant difference was found in image, clinical symptoms, and past medical history between the two groups (p > 0.05). Notably, the median time for relieving blood oxygen saturation in the conventional treatment group was 11 days (IQR, 8-14.25), while that in the HSBD group was only 6 days (IQR, 3.25-10.75), which was significantly shortened by 4.09 days (95%CI, 2.07-6.13; p= 0.0001), compared with the conventional treatment group. After repeated measurement design analysis, the main effect within times (p< 0.001) and the main effect were significantly different under the oxygen saturation dimension between two groups (p= 0.004). However, time and group interaction were observed no significant difference (p= 0.094). After 14 days of treatment, the improvement ratio of the HSBD group over the conventional treatment group was 1.20 (95%CI, 0.89-1.61). CONCLUSION: For severe COVID-19 patients, the HSBD has a tendency to shorten the time for relieving blood oxygen saturation. After taking a course of HSBD, the effect can be more obvious.

Chinese Medicine Formula Huashibaidu Granule Early Treatment for Mild COVID-19 Patients: An Unblinded, Cluster-Randomized Clinical Trial.

Background: Previous research suggested that Chinese Medicine (CM) Formula Huashibaidu granule might shorten the disease course in coronavirus disease 2019 (COVID-19) patients. This research aimed to investigate the early treatment effect of Huashibaidu granule in well-managed patients with mild COVID-19. Methods: An unblinded cluster-randomized clinical trial was conducted at the Dongxihu FangCang hospital. Two cabins were randomly allocated to a CM or control group, with 204 mild COVID-19 participants in each cabin. All participants received conventional treatment over a 7 day period, while the ones in CM group were additionally given Huashibaidu granule 10 g twice daily. Participants were followed up to their clinical endpoint. The primary outcome was worsening symptoms before the clinical endpoint. The secondary outcomes were cure and discharge before the clinical endpoint and alleviation of composite symptoms after the 7 days of treatment. Results: All 408 participants were followed up to their clinical endpoint and included in statistical analysis. Baseline characteristics were comparable between the two groups (P > 0.05). The number of worsening patients in the CM group was 5 (2.5%), and that in the control group was 16 (7.8%) with a significant difference between groups (P = 0.014). Eight foreseeable mild adverse events occurred without statistical difference between groups (P = 0.151). Conclusion: Seven days of early treatment with Huashibaidu granule reduced the likelihood of worsening symptoms in patients with mild COVID-19. Our study supports Huashibaidu granule as an active option for early treatment of mild COVID-19 in similar well-managed medical environments. Clinical Trial Registration:www.chictr.org.cn/showproj.aspx?proj=49408, identifier: ChiCTR2000029763.

Tojapride Reverses Esophageal Epithelial Inflammatory Responses on Reflux Esophagitis Model Rats.

OBJECTIVE: To investigate the mechanism of Tojapride, a Chinese herbal formula extract, on strengthening the barrier function of esophageal epithelium in rats with reflux esophagitis (RE). METHODS: Ten out of 85 SD rats were randomly selected as the sham group (n10), and 75 rats were developed a reflux esophagitis model (RE) by the esophageal and duodenal side-to-side anastomosis. Fifty successful modeling rats were divided into different medicated groups through a random number table including the model, low-, medium-, and high-dose of Tojapride as well as omeprazole groups (n10). Three doses of Tojapride [5.73, 11.46, 22.92 g/(kg•d)] and omeprazole [4.17 mg/(kg•d)] were administrated intragastrically twice daily for 3 weeks. And the rats in the sham and model groups were administered 10 mL/kg distilled water. Gastric fluid was collected and the supernatant was kept to measure for volume, pH value and acidity. Esophageal tissues were isolated to monitor the morphological changes through hematoxylin-eosin (HE) staining, and esophageal epithelial ultrastructure was observed by transmission electron microscopy. The expressions of nuclear factor kappa-light-chain-enhancer of activated B cells p65 (NF-KBp65), κB kinase beta (IKKß), occludin, and zonula occludens-1 (ZO-1) in the esophageal tissues were measured by immunohistochemistry and Western blot, respectively. RESULTS: The gastric pH value in the model group was significantly lower than the sham group (P<0.05). Compared with the model group, gastric pH value in the omeprazole and medium-dose of Tojapride groups were significantly higher (P<0.05). A large area of ulceration was found on the esophageal mucosa from the model rats, while varying degrees of congestion and partially visible erosion was observed in the remaining groups. Remarkable increase in cell gap width and decrease in desmosome count was seen in RE rats and the effect was reversed by Tojapride treatment. Compared with the sham group, the IKKß levels were significantly higher in the model group (P<0.05). However, the IKKß levels were down-regulated after treatment by all doses of Tojapride (P<0.01 or P<0.05). The occluding and ZO-1 levels decreased in the model group compared with the sham group (Ps0.01 or Ps0.05), while both indices were significantly up-regulated in the Tojapride-treated groups (P<0.01 or P<0.05). CONCLUSIONS: Tojapride could improve the pathological conditions of esophageal epithelium in RE rats. The underlying mechanisms may involve in down-regulating the IKKß expression and elevating ZO-1 and occludin expression, thereby alleviating the inflammation of the esophagus and strengthening the barrier function of the esophageal epithelium.

Efficacy and safety of Chinese herbal medicine versus Lopinavir-Ritonavir in adult patients with coronavirus disease 2019: A non-randomized controlled trial.

BACKGROUND: Treatments for coronavirus disease 2019 (COVID-19) are limited by suboptimal efficacy. METHODS: From January 30, 2020 to March 23, 2020, we conducted a non-randomised controlled trial, in which all adult patients with laboratory-confirmed COVID-19 were assigned to three groups non-randomly and given supportive treatments: Group A, Lopinavir-Ritonavir; Group B, Huashi Baidu Formula (a Chinese medicineformula made by the China Academy of Chinese Medical Sciences to treat COVID-19, which is now in the clinical trial period) and Lopinavir-Ritonavir; and Group C, Huashi Baidu Formula. The use of antibiotics, antiviruses, and corticosteroids was permitted in Group A and B. Traditional Chinese medicine injections were permitted in Group C. The primary outcomes were clinical remission time (interval from admission to the first time the patient tested negatively for novel coronavirus or an obvious improvement was observed from chest CT) and clinical remission rate (number of patients whose clinical time was within 16 days/total number of patients). RESULTS: A total of 60 adult patients with COVID-19 were enrolled at sites in Wuhan, China, and the sample size of each group was 20. In Groups A, B and C, the clinical remission rates were 95.0%%(19/20), 100.0%%(20/20) and 100.0%%(20/20), respectively. Compared with Groups A and B, the clinical remission time of Group C was significantly shorter (5.9 days vs. 10.8 days, p < 0.05; 5.9 days vs. 9.7 days, p < 0.05). There was no significant difference among Groups A, B, and C in terms of the time taken to be released from quarantine. The clinical biochemical indicators and safety indexes showed no significant differences among the three groups. CONCLUSIONS: Our findings suggest that Lopinavir-Ritonavir has some efficacy in the treatment of COVID-19, and the Huashi Baidu Formula might enhance this effect to an extent. In addition, superiority was displayed in the treatment of COVID-19 through a combination of the Huashi Baidu Formula and traditional Chinese medicine injection. In future, well-designed prospective double-blinded randomised control trials are required to confirm our findings.

Association between early treatment with Qingfei Paidu decoction and favorable clinical outcomes in patients with COVID-19: A retrospective multicenter cohort study.

The coronavirus disease 2019 (COVID-19) epidemic has been almost controlled in China under a series of policies, including "early diagnosis and early treatment". This study aimed to explore the association between early treatment with Qingfei Paidu decoction (QFPDD) and favorable clinical outcomes. In this retrospective multicenter study, we included 782 patients (males, 56 %; median age 46) with confirmed COVID-19 from 54 hospitals in nine provinces of China, who were divided into four groups according to the treatment initiation time from the first date of onset of symptoms to the date of starting treatment with QFPDD. The primary outcome was time to recovery; days of viral shedding, duration of hospital stay, and course of the disease were also analyzed. Compared with treatment initiated after 3 weeks, early treatment with QFPDD after less than 1 week, 1-2 weeks, or 2-3 weeks had a higher likelihood of recovery, with adjusted hazard ratio (HR) (95 % confidence interval [CI]) of 3.81 (2.65-5.48), 2.63 (1.86-3.73), and 1.92 (1.34-2.75), respectively. The median course of the disease decreased from 34 days to 24 days, 21 days, and 18 days when treatment was administered early by a week (P < 0.0001). Treatment within a week was related to a decrease by 1-4 days in the median duration of hospital stay compared with late treatment (P<0.0001). In conclusion, early treatment with QFPDD may serve as an effective strategy in controlling the epidemic, as early treatment with QFPDD was associated with favorable outcomes, including faster recovery, shorter time to viral shedding, and a shorter duration of hospital stay. However, further multicenter, prospective studies with a larger sample size should be conducted to confirm the benefits of early treatment with QFPDD.

Development of Rapid Advice Guidelines for the Treatment of Coronavirus Disease 2019 with Traditional Chinese Medicine.

The worldwide spread of the 2019 novel coronavirus has become a profound threat to human health. As the use of medication without established effectiveness may result in adverse health consequences, the development of evidence-based guidelines is of critical importance for the clinical management of coronavirus disease (COVID-19). This research presents methods used to develop rapid advice guidelines on treating COVID-19 with traditional Chinese medicine (TCM). We have followed the basic approach for developing WHO rapid guidelines, including preparing, developing, disseminating and updating each process. Compared with general guidelines, this rapid advice guideline is unique in formulating the body of evidence, as the available evidence for the treatment of COVID-19 with TCM is from either indirect or observational studies, clinical first-hand data together with expert experience in patients with COVID-19. Therefore, our search of evidence not only focuses on clinical studies of treating COVID-19 with TCM but also of similar diseases, such as pneumonia and influenza. Grading of recommendations assessment, development and evaluation (GRADE) methodology was adopted to rate the quality of evidence and distinguish the strength of recommendations. The overall certainty of the evidence is graded as either high, moderate, low or very low, and to give either "strong" or "weak" recommendations of each TCM therapy. The output of this paper will produce the guideline on TCM for COVID-19 and will also provide some ideas for evidence collection and synthesis in the future development of rapid guidelines for COVID-19 in TCM as well as other areas.

Sealing the Pores of PEO Coating with Mg-Al Layered Double Hydroxide: Enhanced Corrosion Resistance, Cytocompatibility and Drug Delivery Ability.

In recent years, magnesium (Mg) alloys show a promising application in clinic as degradable biomaterials. Nevertheless, the poor corrosion resistance of Mg alloys is the main obstacle to their clinical application. Here we successfully seal the pores of plasma electrolytic oxidation (PEO) coating on AZ31 with Mg-Al layered double hydroxide (LDH) via hydrothermal treatment. PEO/LDH composite coating possess a two layer structure, an inner layer made up of PEO coating (~5 µm) and an outer layer of Mg-Al LDH (~2 µm). Electrochemical and hydrogen evolution tests suggest preferable corrosion resistance of the PEO/LDH coating. Cytotoxicity, cell adhesion, live/dead staining and proliferation data of rat bone marrow stem cells (rBMSCs) demonstrate that PEO/LDH coating remarkably enhance the cytocompatibility of the substrate, indicating a potential application in orthopedic surgeries. In addition, hemolysis rate (HR) test shows that the HR value of PEO/LDH coating is 1.10 ± 0.47%, fulfilling the request of clinical application. More importantly, the structure of Mg-Al LDH on the top of PEO coating shows excellent drug delivery ability.

The Effect of Tong-Xie-Yao-Fang on Intestinal Mucosal Mast Cells in Postinfectious Irritable Bowel Syndrome Rats.

Objective. To investigate the effects of Tong-Xie-Yao-Fang (TXYF) on intestinal mucosal mast cells in rats with postinfectious irritable bowel syndrome (PI-IBS). Design. PI-IBS rat models were established using a multistimulation paradigm. Then, rats were treated with TXYF intragastrically at doses of 2.5, 5.0, and 10.0 g·kg-1·d-1 for 14 days, respectively. Intestinal sensitivity was assessed based on abdominal withdrawal reflex (AWR) scores and fecal water content (FWC). Mast cell counts and the immunofluorescence of tryptase and c-Fos in intestinal mucosa were measured; and serum IL-1ß, TNF-α, and histamine levels were determined. Results. AWR reactivity and FWC which were significantly increased could be observed in PI-IBS rats. Remarkably increased mast cell activation ratio in intestinal mucosa, together with increased serum TNF-α and histamine levels, could also be seen in PI-IBS rats; furthermore, PI-IBS-induced changes in mast cell activation and level of serum TNF-α and histamine could be reversed by TXYF treatment. Meanwhile, tryptase and c-Fos expression were also downregulated. Conclusion. TXYF improves PI-IBS symptoms by alleviating behavioral hyperalgesia and antidiarrhea, the underlying mechanism of which involves the inhibitory effects of TXYF on activating mucosal mast cells, downregulating tryptase and c-Fos expression, and reducing serum TNF-α and histamine levels.

Mn-containing titanium surface with favorable osteogenic and antimicrobial functions synthesized by PIII&D.

Reasonable incorporation of manganese into titanium is believed to be able to enhance the osteogenic and antibacterial activities of orthopedic implants. However, it is still a challenge to compromise Mn-induced cytotoxicity and better develop its biocompatibility and antimicrobial ability. To pinpoint this issue, a stable Mn ion release platform was created on Ti using plasma immersion ion implantation and deposition (PIII&D) technique. Compared with as-etched titanium, as a result, promoted antibacterial abilities against gram-negative bacteria species and enhanced osteogenic-related gene expressions on rBMMSC were observed on Mn-containing sample. Meanwhile, the Mn-containing samples showed no obvious cytotoxicity. Our results here provide insight to be better understanding the relationships between additives-induced biological performance and the dose, state, and stability of the doped element.

Enhanced Corrosion Resistance and Biocompatibility of Magnesium Alloy by Mg-Al-Layered Double Hydroxide.

Magnesium (Mg) and its alloys have been suggested as revolutionary biodegradable materials. However, fast degradation hinders its clinic application. To improve the corrosion resistance and biocompatibility of Mg-Nd-Zn-Zr alloy (JDBM), magnesium-aluminum-layered double hydroxide (Mg-Al LDH) was successfully introduced into Mg(OH)2 coating by hydrothermal treatment. The anions in the interlayer of Mg-Al LDH can be replaced by chloride ions, resulting in a relatively low chloride ion concentration near the surface of the coating. The favorable corrosion resistance of the coating was proved by polarization curves and hydrogen collection test. The Mg-Al LDH significantly promoted cell adhesion, migration and proliferation in vitro. In addition, the coating almost fulfilled the request of the clinical application in the hemolysis ratio test. Finally, in vivo results indicated that the coating offered the greatest long-lasting protection from corrosion and triggered the mildest inflammation comparing to the pure Mg(OH)2 coatings and untreated magnesium alloy. Mg(OH)2 coating containing Mg-Al LDH in the present study shows a promising application in improving anticorrosion and biocompatibility of Mg alloys, and might act as a platform for a further modification of Mg alloys ascribed to its special layer structure.

Antibacterial activity and cytocompatibility of titanium oxide coating modified by iron ion implantation.

In this work, zero valent iron nanoparticles (Fezero-NPs) and iron oxide nanoparticles (Feox-NPs) were synthesized at the subsurface and surface regions of titanium oxide coatings (TOCs) by plasma immersion ion implantation. This novel Fe-NPs/TOC system showed negligible iron releasing, great electron storage capability and excellent cytocompatibility in vitro. Importantly, the system showed selective antibacterial ability which can kill Staphylococcus aureus under dark conditions but has no obvious antibacterial effect against Escherichia coli. Owing to a bipolar Schottky barrier between Fezero-NPs/TOC and Fezero-NPs/Feox-NPs, electrons could be captured by the Fezero-NPs bounded at the subsurface region of the coating. This electron storage capability of the Fe-NPs/TOC system induced extracellular electron transportation and accumulation of adequate valence-band holes (h(+)) at the external side, which caused oxidation damage to S. aureus cells in the dark. No obvious biocide effect against E. coli resulted from lack of electron transfer ability between E. coli and substrate materials. This work may open up a novel and controlled strategy to design coatings of implants with antibacterial ability and cytocompatibility for medical applications.