Early Stages Of Implantation Research Articles

Effect of hematoma on early degradation behavior of magnesium after implantation.

The corrosion of magnesium (Mg)-based bioabsorbable implanting devices is influenced by implantation environment which dynamically changes by biological response including wound healing. Understanding the corrosion mechanisms along the healing process is essential for the development of Mg-based devices. In this study, a hematoma model was created in a rat femur to analyze Mg corrosion with hematoma in the early stage of implantation. Pure Mg specimen (99.9%,ϕ1.2 × 6 mm) was implanted in rat femur under either hematoma or non-hematoma conditions. After a designated period of implantation, the specimens were collected and weighed. The insoluble salts formed on the specimen surfaces were analyzed using scanning electron microscopy, energy-dispersive x-ray spectroscopy, and Raman spectroscopy on days 1, 3, and 7. The results indicate that hematomas promote Mg corrosion and change the insoluble salt precipitation. The weight loss of the hematoma group (27.31 ± 5.91 µg mm-2) was significantly larger than that of the non-hematoma group (14.77 ± 3.28 µg mm-2) on day 7. In the non-hematoma group, carbonate and phosphate were detected even on day 1, but the only latter was detected on day 7. In the hematoma group, hydroxide was detected on day 1, followed by the formation of carbonate and phosphate on days 3 and 7. The obtained results suggest the hypoxic and acidic microenvironment in hematomas accelerates the Mg corrosion immediately after implantation, and the subsequent hematoma resorption process leads to the formation of phosphate and carbonate with organic molecules. This study revealed the risk of hematomas as an acceleration factor of the corrosion of Mg-based devices leading to the early implant failure. It is important to consider this risk in the design of Mg-based devices and to optimize surgical procedures controlling hemorrhage at implantation and reducing unexpected bleeding after surgery.

Modified Titanium Implants Satisfy the Demands of Diabetic Osseointegration via Sequential Regulation of Macrophages and Mesenchymal Stem Cells.

The application of titanium (Ti) implants for patients with diabetes mellitus (DM) is still facing a significant challenge due to obstacles such as hyperglycemia, reactive oxygen species (ROS), and chronic inflammation, which hinders osseointegration. To address this issue, a Ti implant with dual functions of regulating polarization of macrophages and facilitating osseointergration is developed via hydrothermal reaction and hydrogel coating. The reactive oxygen species (ROS) and glucose (Glu) responsive hydrogel coating can locally deliver adenosine (ADO) in the early stage of implantation. The controlled release of ADO regulated the phenotype of macrophages, restored oxidative balance, and enhanced mitochondrial function during the early stages of implantation. Subsequently, strontium (Sr) ions will be released to promote osteogenic differentiation and proliferation of mesenchymal stem cells (MSCs), as the hydrogel coating degraded. It eventually leads to bone reconstruction during the late stages, aligning with the biological cascade of bone healing. The modified Ti implants showed effective osteogenesis for bone defects in DM patients, shedding light on the design and biological mechanisms of surface modification. This research offers promising potential for improving the treatment of bone-related complications in diabetic patients.

Contribution of Tregs to the promotion of constructive remodeling after decellularized extracellular matrix material implantation

Host remodeling of decellularized extracellular matrix (dECM) material through the appropriate involvement of immune cells is essential for achieving functional organ/tissue regeneration. As many studies have focused on the role of macrophages, only few have evaluated the role of regulatory T cells (Tregs) in dECM remodeling. In this study, we used a mouse model of traumatic muscle injury to determine the role of Tregs in the constructive remodeling of vascular-derived dECM. According to the results, a certain number of Tregs could be recruited after dECM implantation. Notably, using anti-CD25 to reduce the number of Tregs recruited by the dECM was significantly detrimental to material remodeling based on a significant reduction in the number of M2 macrophages. In addition, collagen and elastic fibers, which maintain the integrity and mechanical properties of the material, rapidly degraded during the early stages of implantation. In contrast, the use of CD28-SA antibodies to increase the number of Tregs recruited by dECM promoted constructive remodeling, resulting in a decreased inflammatory response at the material edge, thinning of the surrounding fibrous connective tissue, uniform infiltration of host cells, and significantly improved tissue remodeling scores. The number of M2 macrophages increased whereas that of M1 macrophages decreased. Moreover, Treg-conditioned medium further enhanced material-induced M2 macrophage polarization in vitro. Overall, Treg is an important cell type that influences constructive remodeling of the dECM. Such findings contribute to the design of next-generation biomaterials to optimize the remodeling and regeneration of dECM materials.

P-442 Genome edition in endometrial stroma cells leading to decreased expression of UDP-glucuronic acid decarboxylase I (UXS1) alters the molecular interactions of the implantation area

Abstract Study question Does UDP-glucuronic acid decarboxylase 1 (UXS1) expression in endometrial stroma cells have a direct effect on the early stages of implantation? Summary answer Decreased expression of UXS1 was found to alter adhesion, invasion, development and function related genes of implantation in 3D cultures in a time dependent manner. What is known already The implantation process is governed by a complex interaction of genes and molecular pathways. Some of those genes are well-defined, however, as fertility problems increase with escalating rates of recurrent implantation failure or abortions, with an effort to reveal those genes that may be more significant than known for implantation RNA-seq analyses are used. UDP-glucuronic acid decarboxylase 1 (UXS1) is an enzyme involved in the detoxification and conversion of UDP-glucuronic acid to UDP-xylose. Loss of UXS1 led to defective glycosylation, increased protein degradation, and decreased overall protein levels, but no direct relation to has been stated before. Study design, size, duration Two different Matrigel based 3D culture systems were constructed with labeled mouse endometrium epithelial cells, stroma cells and blastocysts for 24-72 hours (n = 24). Sorted cells were sequenced for RNA for determination of differentially expressed genes. Of over 4000 genes, a highly expressed one was UXS1 in the endometrial stroma cells, The gene was knocked out via CRISPR/Cas9. The impact of decline of UXS1 in stroma cells on implantation parameters has been evaluated. Participants/materials, setting, methods CB6F1 female mice were superovulated. Blastocysts were obtained, endometrium was used for isolation of epithelial and stroma cells. 3D cultures were constructed for RNA-seq analysis. Three gRNAs were designed for CRISPR/Cas9 experiments. Cultures were constructed with knock out stroma and wild epithelial cells, wild blastocysts. On hours 24 and 72 of culture, gene and protein expression analyses for e-cadherin, MMP9, entactin, LIF; Hoxa10, Wnt4, ESR1, PR, fibronectin have been accomplished. Supported by TUBITAK 118S676. Main results and the role of chance All adherence molecules tested (e-cadherin, entactin, fibronectin) have shown significant increase compared to non targeted (the cell has Cas9, but no gRNA) groups (p < 0.00001). As e-cadherin has decreased detrimentally from 24 to 72 hours, fibronectin has continued to increase. LIF, an important gene for embryo-blastocyst interphase, has increased steeply and then decreased in the long term culture (p < 0.00001). ESR1 and PR (estrogen and progesterone receptors) increased compared to non-targeted groups but they were lower than the control groups with no genome edition (p < 0.01). The invasion gene MMP9 has increased steeply in the first 24 hours, then declined suddenly at hour 72 (p < 0.0001). The developmental genes Wnt4 and Hoxa10 were also affected significantly, as Wnt4 has decreased and Hoxa10 has increased compared to non-targeted groups (p < 0.001, p < 0.0001 respectively), however the expressions did not change from 24 to 72 hours. These findings were mostly supported by the protein expressions depicted by IF staining. The data can be interpreted as UXS1 has some fundamental effects during the implantation process as its decreased expression changes the adhesion and invasion patterns with unexpectedly high and low pattern, and it deteriorates differential expression of LIF during the critical interaction of endometrial cells and the blastocyst. Limitations, reasons for caution - This is a 3D in vitro implantation model constructed with mouse cells, so it cannot reflect in vivo process perfectly. - The genome edition of primary cells can show lower yield than cell lines. - There are numerous parameters of implantation, more tests can always be added. Wider implications of the findings - Data arising from various RNAseq analyses for implantation is accumulating and it is possible to find new genes and their connections and contribution can be revealed. - The new genes tested in vitro can further be re-examined in knock out mouse models or can be scanned in the abortus materials. Trial registration number not applicable

Anti-fouling coating with ROS-Triggered On-Demand regulation of inflammation to favor tissue healing on vascular devices

Unhealthy vascular tissue healing after stenting is primarily triggered by endothelial dysfunction and excessive smooth muscle cell proliferation, which is induced and aggravated by local thrombosis and excessive inflammation. Excessive inflammatory response is closely related to elevated concentrations of reactive oxygen species (ROS). Here, an environment-friendly coating strategy termed “Anti-fouling plus” with inflammatory self-regulation ability was proposed. Upon this, membrane-mimicking copolymer MA(PCLA) served as the antifouling coating, effectively inhibiting coagulation and inflammation during the early stage of implantation. Furthermore, a ROS-responsive prodrug was drawn into the coating to promote tissue healing. A molecular prodrug of thioketal-bearing dexamethasone was engineered to be released in a controlled and responsive manner in response to externally high levels of ROS. The released dexamethasone exhibited highly effective anti-inflammation properties after implantation. The combination of ROS-responsive prodrug and membrane-mimicking antifouling interface strategy intelligently integrated inflammation responsiveness and regulation, which could mediate a gentle vascular microenvironment and thus promote vascular remodeling. In vivo stent implantation studies demonstrated that the proposed “Anti-fouling plus” coating effectively inhibited neointima hyperplasia, modulated the inflammatory response and promoted endothelialization, offering promising surface modification approaches for vascular stents.

Two-electron oxidized polyphenol chemistry-inspired superhydrophilic drug-carrying coatings for the construction of multifunctional nasolacrimal duct stents.

Nasolacrimal duct obstruction due to infection, inflammation, or excessive fibroblast proliferation may result in persistent tearing, intraocular inflammation, or even blindness. In this study, surface engineering techniques are applied to nasolacrimal duct stents for the first time. Based on the functioning of marine mussels, "one-pot" and "stepwise" methods were employed to construct a novel multifunctional superhydrophilic PDA/RAP coating using dopamine and rapamycin. Micron-sized rapamycin crystals combined with nano-sized polydopamine particles form a micro-nano topographical structure. Therefore, acting synergistically with in situ-generated hydrophilic groups (amino, carboxyl, and phenolic hydroxyl), they impart excellent and long-lasting superhydrophilicity to the nasolacrimal duct stent. The PDA/RAP coating effectively maintained the stability of the initial microenvironment during stent implantation by inhibiting the onset of acute inflammation and infection during the early stages of implantation. Meanwhile, the rapamycin crystals, supported by the superhydrophilic platform, exhibited a sustained-release capability that helped them to better exert their anti-inflammatory, antibacterial, and anti-fibroblast proliferative properties, ensuring conducive conditions for the rapid repair of nasolacrimal duct epithelial cells, verified by a series of experiments. In conclusion, the PDA/RAP hydrophilic coating has anti-inflammatory, antifibrotic, antibacterial, and antithrombotic properties, offering a new strategy to address restenosis following clinical nasolacrimal duct stent implantation.

Development and Future Trends of Protective Strategies for Magnesium Alloy Vascular Stents.

Magnesium alloy stents have been extensively studied in the field of biodegradable metal stents due to their exceptional biocompatibility, biodegradability and excellent biomechanical properties. Nevertheless, the specific in vivo service environment causes magnesium alloy stents to degrade rapidly and fail to provide sufficient support for a certain time. Compared to previous reviews, this paper focuses on presenting an overview of the development history, the key issues, mechanistic analysis, traditional protection strategies and new directions and protection strategies for magnesium alloy stents. Alloying, optimizing stent design and preparing coatings have improved the corrosion resistance of magnesium alloy stents. Based on the corrosion mechanism of magnesium alloy stents, as well as their deformation during use and environmental characteristics, we present some novel strategies aimed at reducing the degradation rate of magnesium alloys and enhancing the comprehensive performance of magnesium alloy stents. These strategies include adapting coatings for the deformation of the stents, preparing rapid endothelialization coatings to enhance the service environment of the stents, and constructing coatings with self-healing functions. It is hoped that this review can help readers understand the development of magnesium alloy cardiovascular stents and solve the problems related to magnesium alloy stents in clinical applications at the early implantation stage.

3D Printing Drug-Free Scaffold with Triple-Effect Combination Induced by Copper-Doped Layered Double Hydroxides for the Treatment of Bone Defects.

Tissue-engineered poly(l-lactide) (PLLA) scaffolds have been widely used to treat bone defects; however, poor biological activities have always been key challenges for its further application. To address this issue, introducing bioactive drugs or factors is the most commonly used method, but there are often many problems such as high cost, uncontrollable and monotonous drug activity, and poor bioavailability. Here, a drug-free 3D printing PLLA scaffold with a triple-effect combination induced by surface-modified copper-doped layered double hydroxides (Cu-LDHs) is proposed. In the early stage of scaffold implantation, Cu-LDHs exert a photothermal therapy (PTT) effect to generate high temperature to effectively prevent bacterial infection. In the later stage, Cu-LDHs can further have a mild hyperthermia (MHT) effect to stimulate angiogenesis and osteogenic differentiation, demonstrating excellent vascularization and osteogenic activity. More importantly, with the degradation of Cu-LDHs, the released Cu2+ and Mg2+ provide an ion microenvironment effect and further synergize with the MHT effect to stimulate angiogenesis and osteogenic differentiation, thus more effectively promoting the healing of bone tissue. This triple-effect combined scaffold exhibits outstanding antibacterial, osteogenic, and angiogenic activities, as well as the advantages of low cost, convenient procedure, and long-term efficacy, and is expected to provide a promising strategy for clinical repair of bone defects.

Finite element modeling to predict the influence of anatomic variation and implant placement on performance of biological intervertebral disc implants.

Tissue-engineered intervertebral disc (TE-IVD) constructs are an attractive therapy for treating degenerative disc disease and have previously been investigated in vivo in both large and small animal models. The mechanical environment of the spine is notably challenging, in part due to its complex anatomy, and implants may require additional mechanical support to avoid failure in the early stages of implantation. As such, the design of suitable support implants requires rigorous validation. We created a FE model to simulate the behavior of the IVD cages under compression specific to the anatomy of the porcine cervical spine, validated the FE model using an animal model, and predicted the effects of implant location and vertebral angle of the motion segment on implant behavior. Specifically, we tested anatomical positioning of the superior vertebra and placement of the implant. We analyzed corresponding stress and strain distributions. Results demonstrated that the anatomical geometry of the porcine cervical spine led to concentrated stress and strain on the posterior side of the cage. This stress concentration was associated with the location of failure of the cages reported in vivo, despite superior mechanical properties of the implant. Furthermore, placement of the cage was found to have profound effects on migration, while the angle of the superior vertebra affected stress concentration of the cage. This model can be utilized both to inform surgical procedures and provide insight on future cage designs and can be adopted to models without the use of in vivo animal models.

Preparation of cerium-containing nanoporous titanium coatings for osseointegration and their promotion of osteogenic differentiation and anti-inflammatory properties

Conventional implants face many problems, such as failure to form good osseointegration and peri-implantitis in the early stage of implantation. It has been shown that hydroxyapatite (HA) has good osteoconductive ability. Also considering the potential of cerium oxide in osteogenesis and anti-inflammation, we prepared cerium-containing nanoporous HA coatings on the surface of pure titanium using the micro-arc oxidation (MAO) technique. The surface morphology of the coating was observed by scanning electron microscopy (SEM). The mechanical strength of the coating was examined by the ultrasonic oscillator. The elemental composition of the coating was examined by energy spectrum analysis (EDS). The ion release capacity of the cerium-containing coatings was examined by inductively coupled plasma emission spectrometry (ICP-OES). The hydrophilic properties of the coatings were examined by the hydrophilic angle test. In vitro, experiments were performed using rat bone marrow mesenchymal stem cells (BMSCs) and mouse mononuclear macrophages (Raw264.7). The biosafety of the cerium-containing coating was verified by live-dead staining and CCK-8 proliferation assay. The osteogenic and anti-inflammatory ability of the cerium-containing coating was examined by immunofluorescence staining and quantitative polymerase chain reaction (q-PCR). In addition, ion experiments were used to further demonstrate the osteogenic and anti-inflammatory potential of cerium ions. Subsequent animal experiments further demonstrated the osteoinductive potential of the cerium-containing HA coating. In conclusion, our cerium (HA)-containing coatings prepared by micro-arc oxidation on titanium surfaces show excellent osteogenic and anti-inflammatory properties, which are expected to improve the functionality of clinical implants and also lay the foundation for the clinical application of cerium ions.

Anti-fouling plus: Engineered stent coating with inflammation-regulation capability enables enhanced tissue healing

Coagulation, inflammation, and hyperplasia frequently restrict the effectiveness of cardiovascular stents. It is critical to modify stent surfaces to allow for in situ tissue healing. Interrelated coagulation and inflammation can impede endothelialization and are critical to the long-term performance of cardiovascular implants. This study proposes a relatively bio-inert “Anti-fouling plus” coating that is effective in anti-coagulation and anti-inflammation at the early stage of implantation and provides mild inflammatory responses during tissue remodeling process. The phosphorylcholine (PC)-based polymer PM(PCLA) is reacted onto a polydopamine-treated polylactic acid (PLA) surface. PC-based polymers that mimic cell membranes present remarkable antiinflammation and anticoagulation properties. The composite of epigallocatechin gallate (EGCG) and tempol is loaded on the PM(PCLA) coating to achieve “anti-fouling plus” which can mediate inflammatory responses by scavenging reactive oxygen species. In vitro hemocompatibility and cell tests demonstrate the effectiveness of coatings in inhibiting thrombus and inflammation. Interestingly, this study originally reveals a novel strategy that the anti-fouling plus coating can direct vascular tissue healing on stent via promoted endothelialization and mediated contractile smooth muscle cell phenotype by switching inflammatory cells to a pro-repair phenotype during tissue healing process, even if the coating is relatively bio-inert.

Identifying the Incidence, Predictors, Outcomes, and Prevention of Stent Thrombosis (ST) in Post-percutaneous Coronary Revascularization Patients With Drug-Eluting Stents (DES): A Systematic Review.

Stent thrombosis (ST) is a rare but catastrophic event to happen to a stented coronary artery. The incidence of ST has greatly been reduced after the advent of modern drug-eluting stent (DES) implants, which have become the most preferred treatment option in the stenting category for coronary artery disease (CAD). Although the risk reduction by newer category implant provides substantial benefits, the possibility of thrombosis still exists mostly during the early stage of DES implantation. The development of ST after percutaneous coronary intervention (PCI) can be predicted by multiple factors, but advancements in early diagnostic techniques and modified stent types have greatly reduced the occurrence of this complication. Mortality, which is one of the complications of ST, is primarily influenced by patient-related factors such as incomplete treatment duration of dual antiplatelet therapy (DAPT). The duration of DAPT after DES implantation in patients with acute coronary syndrome (ACS) is determined based on individual characteristics, mainly considered in view of bleeding or ischemia risk. Risk evaluation systems like DAPT/precise-DAPT scores help tailor and personalize the duration of DAPT for each individual patient. This systematic review contains pertinent articles extracted from the PubMed database. We retrieved articles from various study categories, encompassing publications from the period spanning 2014 to 2022. Our analysis highlighted results from studies investigating different aspects contributing to ST development. The most favorable prevention option was the use of customized DAPT intervention based on patient-specific predictable factors. Several complications associated with ST were identified, including recurrent ST, major adverse cardiovascular events (MACE) encompassing all-cause mortality (including cardiac and non-cardiac mortality), cerebrovascular accidents (CVA) or transient ischemic attacks (TIA), hospitalization due to heart failure, and myocardial infarction requiring revascularization. Mortality was also observed as a significant outcome. The umbrella term of ST includes multiple causative factors. Although DES has improved patient survival rates vastly with its usage, careful risk factor assessment and required follow-up, in each individual being stented, further guarantee a more promising reduction in late adverse outcomes.

Investigation of zinc-silver alloys as biodegradable metals for orthopedic applications

Biodegradable zinc (Zn) alloys are promising implant materials to restore bone defects in orthopedics. Adding silver (Ag) to Zn not only enhances its mechanical properties but also improves its antibacterial properties. However, the regular pattern of Ag composition on the properties of Zn-xAg alloys remains unclear. In this paper, Zn-Ag alloys with different Ag contents ranging from 0.5 to 6.0% were prepared by casting process and were systematically investigated both in vitro and in vivo. Mechanical tests suggest that the increase of Ag content enhanced the yield strength (YS), ultimate tensile strength (UTS), Vickers hardness, and elongation. Compared with pure Zn, the maximum YS, UTS, Vickers hardness, and elongation were achieved at Zn-6Ag, which were increased by 267%, 295%, 115%, and 172%, respectively. The degradation rate increased and the antibacterial properties were enhanced accordingly. All 25% and most 50% extracts of Zn-Ag alloys significantly promoted the proliferation of MC3T3-E1 cells, except for 50% Zn-6Ag extracts showing cytotoxicity. In the rat femoral condyle model, Zn-2Ag and Zn-4Ag alloys exhibited enhanced osteogenic performance at the early stage of implantation compared with pure Zn. Zn-Ag alloys (especially Zn-2Ag and Zn-4Ag) are identified as promising bone repair materials.

Degradation behavior of ZE21C magnesium alloy suture anchors and their effect on ligament-bone junction repair.

Current materials comprising suture anchors used to reconstruct ligament-bone junctions still have limitation in biocompatibility, degradability or mechanical properties. Magnesium alloys are potential bone implant materials, and Mg2+ has been shown to promote ligament-bone healing. Here, we used Mg-2 wt.% Zn-0.5wt.% Y-1wt.% Nd-0.5wt.% Zr (ZE21C) alloy and Ti6Al4V (TC4) alloy to prepare suture anchors to reconstruct the patellar ligament-tibia in SD rats. We studied the degradation behavior of the ZE21C suture anchor via in vitro and in vivo experiments and assessed its reparative effect on the ligament-bone junction. In vitro, the ZE21C suture anchor degraded gradually, and calcium and phosphorus products accumulated on its surface during degradation. In vivo, the ZE21C suture anchor could maintain its mechanical integrity within 12 weeks of implantation in rats. The tail of the ZE21C suture anchor in high stress concentration degraded rapidly during the early implantation stage (0-4weeks), while bone healing accelerated the degradation of the anchor head in the late implantation stage (4-12weeks). Radiological, histological, and biomechanical assays indicated that the ZE21C suture anchor promoted bone healing above the suture anchor and fibrocartilaginous interface regeneration in the ligament-bone junction, leading to better biomechanical strength than the TC4 group. Hence, this study provides a basis for further research on the clinical application of degradable magnesium alloy suture anchors.

LncRNA CLRN1-AS1 reduces adhesion ability of human trophoblasts via CXCL10/CXCL11

IntroductionTrophoblast cells play an important role in embryo recognition and localization, as well as placental development during embryo implantation. Dysfunction of trophoblastic cells causes pathological changes that lead to insufficient recognition, positioning, and adhesion during embryo implantation, ultimately leading to embryo development has stopped. MethodsHigh-throughput sequencing was used to identify differentially expressed the mRNA and lncRNA in the villi tissue of pregnant women diagnosed with embryo cessation. In vitro implantation cell models, characteristic analysis, and bio information analysis confirmed that CLRN1-AS1 affected the adhesion function of trophoblast cells by influencing the chemokines CXCL10/CXCL11. ResultsHigh throughput sequencing technology was used to identify 438 differentially expressed mRNAs and 41 lncRNAs. The three lncRNAs, namely CLRN1-AS1, USP27X-AS1, and AC104809.4, were screened by the mRNA-lncRNA network. In vitro implantation model suggested that all three lncRNAs could affect the adhesion between trophoblast cells, among which CLRN1-AS1 had the most significant effect. Characteristic analysis and correlation analysis showed that CLRN1-AS1 was closely related to the expression of six adhesion-related genes, LAMA1, FGL2, ITGB2, FBN1, EMP2, and PODN. Cell experiments and re-sequencing confirmed that CLRN1-AS1 could affect the adhesion ability of trophoblast cells to the extracellular matrix, and its process was related to the chemokine CXCL10/CXCL11. DiscussionThese results constructed the network of mRNA-lncRNA and enrichment when embryonic development has stopped and found CLRN1-AS1 highly correlated to failure of embryo implantation, and revealed that CLRN1-AS1 modulates the adhesion ability of trophoblast cells to the extracellular matrix via the chemokines CXCL10/CXCL11 during the early stage of embryo implantation.

P-544 Biochemical markers as a predictor of clinical pregnancy on day 6 after embryo transfer

Abstract Study question Is it possible to predict clinical pregnancy using Machine Learning models on day 6 after embryo transfer to an acceptable degree of certainty? Summary answer Using selected biochemical markers it is possible to build a machine learning model to predict clinical pregnancy. What is known already Human chorionic gonadotropin (β-hCG) is considered the main early predictor of pregnancy. Due to the fact that the highest percentage of spontaneous abortions occurs in the first trimester predicting clinical pregnancy outcomes at the early stages of pregnancy is particularly difficult. The level of B-hcg measured at the early stages of implantation and the dynamics of its increase can help predict clinical pregnancy and predict its further development. However, the specific cut-off points at which pregnancy can be determined vary from study to study, and a different factor is often suggested to increase the certainty of β-hCG-based predictions. Study design, size, duration 1474 single frozen embryo transfers (1205 patients between 23 and 47 years of age), January 2019 -December 2022 were used for data modelling and statistical testing. The dataset consisted of endocrinal markers:β-hCG, PRG (progesterone), E (estradiol) measured on the 6th day after ET and other practitioner-chosen data: age, PGD results, embryo quality status, RIF or RPL history, embryo maturation days as well as pregnancy outcomes. Exclusion criteria were: PRG > 50ng/ml, β-hCG >70 mIU/ml. Participants/materials, setting, methods A machine learning model for predicting clinical pregnancy was trained using the gradient boosting technique. The model used 100 decision trees with 8 leaves, maximal depth of 2 nodes and a learning rate of 0.1. The performance of the model was measured using the accuracy score metric and area under ROC (AUC). Feature importance was based on Shapley values. Additional analysis was performed using statistical testing using a two-sided Student’s t-test. Main results and the role of chance A Machine Learning naive model employed chosen variables to predict clinical pregnancy. The most important variables turned out to be the serum level of β-hCG and PRG on day 6 after embryo-transfer. The final model, limited to those variables, performs with an accuracy of around 83 % (accuracy score = 0.834), the area under ROC (AUC) was 0.927. Based on Shapley values, β-hCG followed by PRG are the most relevant for the model’s predictions. Low PRG concentrations increased the chances of clinical pregnancy. The findings were confirmed by additional statistical analysis. Observations were divided into two groups for which the cut-off point was the level of PRG of 24 ng/ml – the median for the whole group. The probability of clinical pregnancy is higher in the group where the serum PRG is below 24 ng/ml even if β-hCG levels are the same. A statistically significant difference between these groups regarding β-hCG (P value < 0.001) was noticed. In order for serum β-hCG to be used as a more accurate clinical pregnancy predictor its level should be interpreted in the context of PRG serum levels. Limitations, reasons for caution Since in the dataset, only data regarding frozen embryo transfers were included, fresh ETs need to be explored further. The model was based on endocrinal markers as measured on day six after ET hence it cannot be used to interpret those markers as measured on any other date. Wider implications of the findings In order to most accurately inform patients regarding the possible outcomes of embryo-transfers, practitioners should not limit themselves to monitoring β-hCG serum levels but also include PRG as an important prognostic of clinical pregnancy. Trial registration number Not Applicable

Mg‐CS/HA Microscaffolds Display Excellent Biodegradability and Controlled Release of Si and Mg Bioactive Ions to Synergistically Promote Vascularized Bone Regeneration

AbstractFor bone defect repair, it is critical to utilize biomaterials with pro‐angiogenic properties to enhance osteogenesis. Hydroxyapatite (HA)‐based materials widely used in clinical applications have shown much potential for bone repair. However, their predominant calcium phosphate (CaP) composition and poor biodegradability limit their angiogenic potential and hence osteogenic efficiency of HA‐based materials. Here, a magnesium ion‐doped calcium silicate/HA composite microscaffold (Mg‐CS/HA) is fabricated to enhance angiogenesis and osteogenic efficiency for bone repair. Incorporation of CS improved the biodegradability of the Mg‐CS/HA microscaffold, which could simultaneously release Si and Mg bioactive ions during the early stage of implantation, synergistically enhancing angiogenesis and osteogenic efficiency. In co‐culture systems, the synergistic effects of Si and Mg ions promote the “osteogenesis‐angiogenesis coupling effect.” In vivo, the Mg‐CS/HA microscaffold could significantly promote reconstruction of the vascular network and bone regeneration. This study thus provides a new strategy for coordinated release of bioactive ions to achieve synergistic effects on vascularized bone regeneration by HA‐based bone implant materials.

An Observational Comparative Study of the Impact of Accidental Pneumoperitoneum in Understanding the Learning Curve for Totally Extraperitoneal and Extended Totally Extraperitoneal Inguinal Hernia Repair.

Abdominal wall hernia repair is among the fundamental procedures in general surgical practice. Subsequent to the advent of minimally invasive repair, there have been efforts to find the most reliable technique, with easily reproducible results that can be practiced by surgeons worldwide. From an analytical point of view, this study aimed to highlight the advantages and disadvantages of two techniques. A total of 60 participants were divided into two groups of 30 patients: the totally extraperitoneal (TEP) and the extended TEP (eTEP) hernia repair groups. Covariates and outcomes were analyzed using the chi-square and Mann-Whitney U tests. The study was carried out at a tertiary postgraduate teaching hospital in the western zone of Maharashtra, Pune, India, by a single surgeon. The operative procedures were as per standard surgical practice for both groups.The study was conducted to understand types of difficulties observed in the early implantation stages and the learning curve of these procedures. Ten percent of the procedures in the TEP group and 6.7% of procedures in the eTEP group required Veress needle use to manage accidental pneumoperitoneum (P=0.64). The mean operative time in the eTEP group was significantly shorter than that of the TEP group (P=0.031). Compared with the TEP approach, eTEP repair is associated with shorter operative times, owing to a shorter learning curve, a wider-angle view, a wider range of motion for instrument manipulation, and an ergonomically superior operative experience.

Regulation of hypoxic stress and oxidative stress in bone grafting: Current trends and future perspectives

Tissue engineering aims to offer large-scale replacement of damaged organs using implants with the combination of cells, growth factors and scaffolds. However, the intra/peri‑implant region is exposed to severe hypoxic stress and oxidative stress during the early stage of implantation with bone graft materials, which endangers the survival, proliferation and differentiation of seed cells within the implants as well as the host cells surrounding the implants. If the bone graft material could spontaneously and intelligently regulate the hypoxic stress and oxidative stress to a moderate level, it will facilitate the vascularization of the implants and the rapid regeneration of the bone tissue. In this review, we will first introduce the signaling pathways of cellular response under hypoxic stress and oxidative stress, then present the classical material designs and examples in response to hypoxic stress and oxidative stress. And finally, we will address the important role of epigenetic mechanisms in the regulation of hypoxic stress and oxidative stress and describe the potential applications and prospective smart bone graft materials based on novel epigenetic factors against hypoxic stress and oxidative stress in bone repair. The main content of this review is summarized in the following graphical abstract.

The therapeutic effects and optimal timing of granulocyte colony stimulating factor intrauterine administration during IVF-ET

Most of embryos fail to produce live offspring during In Vitro Fertilization-Embryo Transfer (IVF-ET) procedure. There is a dearth of research activity addressing this problem despite the significant population of women suffering from repeated implantation failure after transfer of high-quality of embryos. As a clinically accessible option, granulocyte colony stimulating factor (G-CSF) is often used for the treatment to improve the rates of embryo implantation. However, there are currently no evidence-based standardized protocol for the clinical use of G-CSF. G-CSF was administered into one side of mouse uterine horns and saline was infused into the other side of horns as a control. Intrauterine G-CSF administration showed maximal effects 24 h after administration in enhancing endometrial receptivity and subsequent increase of angiogenesis by demonstrating elevated integrin β3 and OPN and reduced cytotoxicity of NK cells. Furthermore, G-CSF administration 24 h prior to embryo transfer promoted the stability of attached embryos at the early stage of implantation in vitro. Our findings suggest as new consensus criteria providing a potential therapeutic strategy of the clinical use of G-CSF to achieve maximal effects of IVF-ET for patients who are suffering from repeated implantation failure with the problems with endometrial receptivity.