Pru p 3-specific IgE affinity is crucial in severe peach-allergy patients.

Background: Peach allergy is common food allergen. Allergen components-specific antibodies of different isotypes in peach-allergy patients are poorly studied. Factors other than Pru p 3-sIgE levels may be related to severe symptoms. Objective: To evaluated peach component-specific-IgE, IgG1, and IgG4 characteristics in individuals with and without peach allergy, and Pru p 3-sIgE affinity in patients with different clinical symptoms. Methods: Fifteen healthy controls and 32 peach-allergy patients were enrolled. sIgE, sIgG1, and sIgG4 to 5 Escherichia coli-expressed peach-allergen components were determined by enzyme-linked immunosorbent assays. Pru p 3-sIgE affinity was measured in Pru p 3-sIgE-positive patients, using immunoadsorbance. Results: Patients were divided into oral allergy syndrome (OAS) and peach-induced anaphylaxis (PIA) groups. Serum Pru p 1-, Pru p 2-, Pru p 3-, Pru p 4-, and Pru p 7-sIgG1s were detected. Pru p 1- and Pru p 2-sIgG1 levels were higher in healthy controls, but Pru p 3-sIgG1 levels were significantly higher in peach-allergy patients. Pru p 1-, Pru p 3-, and Pru p 4-sIgG4-positivity was significantly greater among patients than among controls. Pru p 3 was the predominant allergen in peach-allergy patients. Allergen-sIgG1 and sIgG4 were similar between OAS and PIA patients. Pru p 3-sIgE levels were significantly higher in PIA patients, but Pru p 3-sIgE-positivity was similar in both groups. In Pru p 3-sIgE-positive patients, Pru p 3-sIgE affinity was significantly higher in PIA than OAS patients. Conclusions: Allergen-sIgG1 was associated with allergen exposure. Both Pru p 3-sIgE levels and affinity are key factors in severe peach-allergy patients.

Editorial for the Special Issue on Laser Additive Manufacturing: Design, Materials, Processes, and Applications, 2nd Edition.

Laser-based additive manufacturing (LAM) represents one of the most forward-thinking transformations in how we conceive, design, and bring to life engineered solutions [...].

Prevalence of aeroallergen sensitization in children in Northern China.

OBJECTIVE: This study aimed to analyze the sensitization rate of different aeroallergens in children of different age, sex, and disease groups, describe the changing trend of different aeroallergens in different ages, and analyze the sensitization risk factors for asthma. METHODS: Children (<18 years old) with suspected atopic diseases who visited the Department of Allergy of Children's Hospital Affiliated to Capital Institute of Pediatrics and underwent a skin prick test (SPT) were retrospectively enrolled from January 2019 to November 2021. RESULTS: A total of 5465 patients (3514 boys, 1951 girls; mean age, 7 ± 3 years) were enrolled. Of them, 3703 patients (67.8%) were sensitized to at least one aeroallergen. Before 4 years of age, mold was the most prevalent aeroallergen (103/380 [27.1%]), whereas after 4 years of age, weed pollen was the most prevalent aeroallergen. After 6 years of age, tree pollen became the second most prevalent aeroallergen. After 12 years of age, the sensitization rate of indoor aeroallergens was lower than that of outdoor aeroallergens. Logistic regression showed that sensitization to mold (odds ratio [OR]:1.4, 95% confidence interval (CI): 1.2-1.7, p < 0.001), animal dander (OR: 1.6, 95% CI: 1.4-1.9, p < 0.001), and polysensitization (OR: 1.4, 95% CI: 1.0-1.8, p = 0.038) were potential sensitization risk factors for asthma. CONCLUSIONS: Mold is an important allergen in early life. Different kinds of allergens affect different age groups. Patients who are sensitized to mold or animal dander or experience polysensitization should be carefully monitored for asthma risk.

Serum levels of specific IgE to cow's milk and its components as predictors of anaphylaxis in Chinese children with cow's milk allergy.

BACKGROUND: Cow's milk allergy (CMA) is one of the most common food allergies in young children. As improved diagnostic tools, allergic tests are inconsistent and limited in predicting anaphylaxis. OBJECTIVE: To explore risk factors for anaphylaxis and to determine practical cut-offs for allergic tests in predicting anaphylaxis. METHODS: This is a prospective cohort study. Children with IgE-mediated CMA were enrolled and divided into three groups (Group 1: non-anaphylaxis; Group 2: GRADE I anaphylaxis; Group 3: GRADE II-IV anaphylaxis that warranted epinephrine). Prick-to-prick tests (PTPs) using fresh cow's milk (CM) were performed. Serum specific IgE (sIgE) against CM and its components, including casein, alpha-lactalbumin, beta-lactoglobulin, and bovine serum albumin were measured. The 90% and 95% positive predictive value (PPV) decision points for predicting anaphylaxis were determined. Potential predictors of anaphylaxis were evaluated in logistic regression models. RESULTS: This study included 134 CMA patients with a median age of 14.4 months. The sensitization rate to any CM component was 89%. Group 3 was more likely to be sensitized to multiple CM components and have higher sIgE levels. The 95% PPV diagnostic decision points of casein-sIgE in predicting anaphylaxis was 13.0 kUA/L. For GRADE II-IV anaphylaxis, casein-sIgE ≥ 54.9 kUA/L could provide a PPV of 88.9%. The elevated casein-sIgE level (OR 14.0, P=0.025) and complicating respiratory allergic diseases (OR 4.8, P=0.022) were independent risk factors for GRADE II-IV anaphylaxis. CONCLUSION: High casein-sIgE levels are strongly associated with CM anaphylaxis. Detection of casein-sIgE may offer an additional value for the prediction of CM anaphylaxis.

HMGN2 and Histone H1.2: potential targets of a novel probiotic mixture for seasonal allergic rhinitis.

Background: Allergic rhinitis (AR) is a common nasal inflammatory disorder that severely affects an individual's quality of life (QoL) and poses a heavy financial burden. In addition to routine treatments, probiotic intervention has emerged as a promising strategy for preventing and alleviating allergic diseases. The main objective of this study was to determine the effect of a novel multi-strain probiotic mixture on AR symptoms and investigate potential targets underlying the probiotic intervention. Methods: A randomized, double-blind, placebo-controlled clinical study was conducted on AR patients who were allergic to autumnal pollens (n = 31). Placebo or a novel probiotic mixture, composed of Lactobacillus rhamnosus (L. rhamnosus) HN001, L. acidophilus NCFM, Bifidobacterium lactis (B. lactis) Bi-07, L. paracasei LPC-37, and L. reuteri LE16, was administered after 2 months. The therapeutic efficacy was evaluated by a symptom assessment scale. Before and during the pollen season, blood samples were collected, and peripheral blood mononuclear cells (PBMCs) were isolated for further tandem mass tags (TMTs)-based quantitative proteomic analyses. Potential targets and underlying pathological pathways were explored using bioinformatics methods. Results: During the pollen season, the rhinoconjunctivitis symptom score of participants who were administered probiotics (probiotic group, n = 15) was significantly lower than those administered placebo (placebo group, n = 15) (P = 0.037). The proteomic analyses identified 60 differentially expressed proteins (DEPs) in the placebo group, and subsequent enrichment analyses enriched a series of pathways and biological processes, including signaling pathways of inflammation, coagulation cascade, lipid, carbohydrate and amino acid metabolic pathways, and transcription and translation processes. Least Absolute Shrinkage and Selection Operator (LASSO) regression extracted five main elements, namely, GSTO1, ATP2A2, MCM7, PROS1, and TRIM58, as signature proteins. A total of 17 DEPs were identified in the probiotic group, and there was no pathway enriched. Comparison of DEPs in the two groups revealed that the expression levels of the high-mobility group nucleosome-binding domain-containing protein 2 (HMGN2) and Histone H1.2 presented an opposite trend with different interventions. Conclusion: Our data showed that AR symptoms alleviated after treatment with the novel multi-strain probiotic mixture, and the proteomic analyses suggested that HMGN2 and Histone H1.2 might be targets of probiotic intervention for seasonal AR.

Cross-Task Mental Workload Recognition Based on EEG Tensor Representation and Transfer Learning.

The accurate evaluation of mental workload of operators in human machine systems is of great significance in ensuring the safety of operators and the correct execution of tasks. However, the effectiveness of EEG based cross-task mental workload evaluation are still unsatisfactory because of the different EEG response patterns in different tasks, which hindered its generalization in real scenario severely. To solve this problem, this paper proposed a feature construction method based on EEG tensor representation and transfer learning, which was verified in various task conditions. Specifically, four working memory load tasks with different types of information were designed firstly. The EEG signals of participants were collected synchronously during task execution. Then, the wavelet transform method was used to perform time-frequency analysis of multi-channel EEG signals, and three-way EEG tensor (time-frequency-channel) features were constructed. EEG tensor features from different tasks were transferred based on the criteria of feature distribution alignment and class-wise discrimination criteria. Finally, the support vector machine was used to construct a 3-class mental workload recognition model. Results showed that compared with the classical feature extraction methods, the proposed method can achieve higher accuracy in both within-task and cross-task mental workload evaluation (91.1% for within-task and 81.3% for cross-task). These results demonstrated that the EEG tensor representation and transfer learning method is feasible and effective for cross-task mental workload evaluation, which can provide theoretical basis and application reference for future researches.

Eosinophilic gastroenteritis: Pathogenesis, diagnosis, and treatment.

ABSTRACT: Eosinophilic gastroenteritis (EGE) is a gastrointestinal disorder of unclear etiology that is characterized by eosinophilic infiltration of the stomach and small intestine, and consists of mucosal, muscular, and serosal subtypes. Eosinophilic infiltration of the gastrointestinal tract is a fundamental histopathological characteristic of EGE and is driven by several T-helper type 2 (Th2)-dependent cytokines and induced by food allergy. Due to the lack of a diagnostic gold standard, EGE has a high rate of delayed diagnosis or misdiagnosis. However, several new diagnostic strategies have been developed, such as novel genetic biomarkers and imaging tests. Although dietary therapy and corticosteroids remain the common choices for EGE treatment, recent decades have seen the emergence of novel treatment alternatives, such as biologics that target particular molecules involved in the pathogenic process. Preliminary investigations and clinical trials have demonstrated the efficacy of biologics and provided additional insights for the era of refractory or corticosteroid-dependent EGE biologics.

Sox2ot /miR-9 /Cthrc1 Promote Proliferation and Migration of Schwann Cells Following Nerve Injury.

The effects of traditional treatments for peripheral nerve injury (PNI) are not ideal, which has prompted the identification of new therapeutic strategies. As unique glial cells in the peripheral nervous system, Schwann cells (SCs) play an important role in the repair of PNI. Recent studies have demonstrated that long noncoding RNAs (lncRNAs) are involved in the regulation of nerve repair after PNI. In this study, we used microarray technology to detect mRNA and lncRNA expression profiles at different time points after PNI and identified lncRNA Sox2ot-miR-9-Cthrc1 as a competitive endogenous RNA (ceRNA) for further investigation. Expression of lncRNA Sox2ot was increased after PNI, and overexpression of Sox2ot promoted SCs migration and proliferation. Mechanistic analyses confirmed that Sox2ot can regulate the expression of Cthrc1 through competitive adsorption of miR-9 in SCs, ultimately affecting SCs migration and proliferation. Our findings reveal the key role of lncRNA Sox2ot in nerve regeneration and provide a new direction for PNI treatment.

The efficacy of a novel smart watch on medicine adherence and symptom control of allergic rhinitis patients: Pilot study.

Background: Allergic rhinitis (AR) is a common allergic airway disorder that is often poorly managed. There is an urgent need to enhance medication adherence in order to improve treatment outcomes in patients with AR. The efficacy of wearable smart watches in improving medication adherence is currently unclear. Objectives: This study aimed to evaluate the efficacy of a novel smart watch in improving medication adherence and symptom control in patients with AR. The reliability of self-reported medication use was also investigated. Methods: This randomized, open-label, parallel controlled, pilot study enrolled adult patients with AR caused by cypress pollen. Patients were randomized in a 1:2 ratio to an intervention group and control group. Smart watches were only distributed to patients in the intervention group. During the cypress pollen season, all patients were required to take oral antihistamines daily and use nasal corticosteroids and antihistamine eye drops as needed. Daily AR symptom scores and medication usage were recorded in both groups. The smart watch was able to identify medication-taking behaviors of patients via artificial intelligence (AI) and relay this information to physicians, who sent short message service reminders to patients who forgot to take oral antihistamines for more than 2 days. Results: During the pollen season, the adherence rate to oral antihistamines in the intervention group (n = 17) was significantly higher than that in the control group (n = 38) (63.3% ± 28.5% versus 43.2% ± 30.2%, P = 0.02). The daily symptom score of the intervention group was lower than that of the control group (2.4 ± 1.1 versus 3.9 ± 1.0, P < 0.001). There was no significant difference in the on-demand medication score between the 2 groups (1.3 ± 0.4 versus 1.5 ± 0.5, P = 0.13). The consistency rate between self-reported nasal corticosteroid usage and the gold standard (ie, human observation of medication usage in the videos recorded by the smart watch) was 20.0% (0%, 53.7%), and the consistency rate between self-reported antihistamine eye drop usage and the gold standard was 24.3% (2.1%, 67.1%). Conclusions: This pilot study showed that the application of smart watches in patients with AR was associated with improved medication adherence and symptom control. Furthermore, the reliability of self-reported medication usage was limited.

Boundary-Sensitive Loss Function With Location Constraint for Hard Region Segmentation.

In computer-aided diagnosis and treatment planning, accurate segmentation of medical images plays an essential role, especially for some hard regions including boundaries, small objects and background interference. However, existing segmentation loss functions including distribution-, region- and boundary-based losses cannot achieve satisfactory performances on these hard regions. In this paper, a boundary-sensitive loss function with location constraint is proposed for hard region segmentation in medical images, which provides three advantages: i) our Boundary-Sensitive loss (BS-loss) can automatically pay more attention to the hard-to-segment boundaries (e.g., thin structures and blurred boundaries), thus obtaining finer object boundaries; ii) BS-loss also can adjust its attention to small objects during training to segment them more accurately; and iii) our location constraint can alleviate the negative impact of the background interference, through the distribution matching of pixels between prediction and Ground Truth (GT) along each axis. By resorting to the proposed BS-loss and location constraint, the hard regions in both foreground and background are considered. Experimental results on three public datasets demonstrate the superiority of our method. Specifically, compared to the second-best method tested in this study, our method improves performance on hard regions in terms of Dice similarity coefficient (DSC) and 95% Hausdorff distance (95%HD) of up to 4.17% and 73% respectively. In addition, it also achieves the best overall segmentation performance. Hence, we can conclude that our method can accurately segment these hard regions and improve the overall segmentation performance in medical images.

Diagnostic accuracy and safety of Dermatophagoides pteronyssinus extracts used for skin prick test.

BACKGROUND: Dermatophagoides pteronyssinus is a common allergen causing allergic diseases in China. The aim of this study was to evaluate the efficacy and safety of D. pteronyssinus extracts produced by Peking Union Medical College Hospital (PUMCH) for the skin prick test (SPT) in the diagnosis of D. pteronyssinus allergy. METHODS: A total of 910 subjects with allergic diseases were prescribed D. pteronyssinus SPT and specific sIgE (sIgE) test among the Outpatients of Department of Allergy, PUMCH from August 10, 2015 to August 30, 2017. Receiver operating characteristic curve (ROC) analysis was performed according to the results of D. pteronyssinus-sIgE detection. The accuracy of D. pteronyssinus extracts used for SPT in the diagnosis of D. pteronyssinus allergy was evaluated under different cutoff values. Adverse events after SPT were recorded to evaluate safety. RESULTS: There were 796 and 618 subjects in the full analysis set (FAS) and the per protocol set (PPS), respectively. The areas under the curve of FAS and PPS were 0.871 and 0.873, respectively. According to the ROC of PPS, the optimal and 95% specificity diagnostic cutoff values of D. pteronyssinus SPT mean wheal diameter were 3.25 and 3.75 mm, respectively. No adverse events occurred. CONCLUSION: The extracts of D. pteronyssinus for SPT were simple, highly accurate, and safe and should be considered for recommendation in the clinical diagnosis of D. pteronyssinus allergy.

Upregulated antimicrobial immune response mediated by neutrophils in the development from allergic rhinitis to asthma.

Background: Allergic rhinitis (AR) and asthma are closely related, and AR is regarded as an important risk factor for the onset of asthma. However, the pathogenesis of the development of asthma from AR is still undefined. Objective: The aim of this study was to investigate the mechanisms underlying the development of asthma from AR by comparing the transcriptome features of patients with AR with and without asthma. Methods: Patients with AR with or without asthma caused by weed pollen who presented to the Allergy Clinic of Peking Union Medical College Hospital were recruited for this study. Peripheral blood samples of all the patients were collected during the weed pollen season (September) when the patients had allergic symptoms and outside the pollen season (November) when the patients had no symptoms. Transcriptomic analysis was conducted, and the differentially expressed genes (DEGs) and enriched immune pathways between the patients with AR with asthma (AR-asthma group) and those without asthma (AR group) were identified. In addition, the expression levels of some pivotal differentially expressed RNAs were quantified using quantitative polymerase chain reaction (PCR). Results: During the weed pollen season, the immune-related Gene Ontology (GO) terms with P value < 0.05, enriched by the upregulated genes in the AR-asthma group compared to the AR group included antifungal humoral response, neutrophil-mediated killing of bacterium, antibacterial humoral response, antimicrobial humoral immune response mediated by antimicrobial peptides, and regulation of the T cell receptor signaling pathway. The immune-related GO terms with P values <0.05 enriched by downregulated genes were positive regulation of natural killer cell-mediated cytotoxicity, microglial cell activation, natural killer cell activation, and leukocyte-mediated cytotoxicity. The GO term of antimicrobial humoral immune response mediated by antimicrobial peptides was upregulated both during and outside the pollen season, and the upregulated expression of three DEGs (LTF, PF4, and ELANE) included in this term was verified through quantitative PCR. Conclusions: The activation of the antimicrobial immune response mediated by neutrophils and the depression of cytotoxicity mediated by natural killer cells may play roles in the progression from AR to asthma.

Birch Pollen Allergens.

Birch belongs to the order Fagales and the family Betulaceae. Birch pollen is one of the most important airborne inhaled allergens in the north temperate zone, leading to allergic rhinitis, asthma and pollen-related food allergy. The sensitization rate to birch pollen is about 8-16% in the general population and 7-57% in patients seen at various allergy centers. Seven birch pollen allergens have been recognized by the International Allergen Nomenclature Sub-committee, with Bet v 1 as the sole major allergen. Component-resolved diagnostics can help to discriminate broad cross-reactivity and false-positive diagnoses of pollen allergy caused by specific IgE to pan-allergens such as Bet v 2, 4 or Bet v 7 from true birch allergy represented by the major allergen Bet v 1-specific IgE. Patients with allergic symptoms to birch pollen showed significantly higher serum anti-Bet v 1 IgE concentrations than asymptomatic individuals with birch sensitization. A higher level of IgE to Bet v 1 also predicted oral allergy syndrome after the ingestion of Rosaceae fruits, nuts, or Apiaceae vegetables, which have cross-reactive homologous allergens with birch allergens. Bet v 1 is one of the first allergens developed using recombinant technology. Many forms of genetically modified Bet v 1 hypo-allergens have been developed and have shown benefit in animal models or even clinical trials of allergen immunotherapy.

Chinese Guideline on Allergen Immunotherapy for Allergic Rhinitis: The 2022 Update.

In the last few decades, there has been a progressive increase in the prevalence of allergic rhinitis (AR) in China, where it now affects approximately 250 million people. AR prevention and treatment include allergen avoidance, pharmacotherapy, allergen immunotherapy (AIT), and patient education, among which AIT is the only curative intervention. AIT targets the disease etiology and may potentially modify the immune system as well as induce allergen-specific immune tolerance in patients with AR. In 2017, a team of experts from the Chinese Society of Allergy (CSA) and the Chinese Allergic Rhinitis Collaborative Research Group (C2AR2G) produced the first English version of Chinese AIT guidelines for AR. Since then, there has been considerable progress in basic research of and clinical practice for AIT, especially regarding the role of follicular regulatory T (TFR) cells in the pathogenesis of AR and the use of allergen-specific immunoglobulin E (sIgE) in nasal secretions for the diagnosis of AR. Additionally, potential biomarkers, including TFR cells, sIgG4, and sIgE, have been used to monitor the incidence and progression of AR. Moreover, there has been a novel understanding of AIT during the coronavirus disease 2019 pandemic. Hence, there was an urgent need to update the AIT guideline for AR by a team of experts from CSA and C2AR2G. This document aims to serve as professional reference material on AIT for AR treatment in China, thus improving the development of AIT across the world.

A real-world retrospective study of safety, efficacy, compliance and cost of combination treatment with rush immunotherapy plus one dose of pretreatment anti-IgE in Chinese children with respiratory allergies.

Background: The efficacy of allergen immunotherapy (AIT) in treating pediatric allergy has been clearly demonstrated, however, many patients hesitate to initiate AIT due to weekly hospital visits during the 3-4 months up-dosing phase. Meanwhile, rush immunotherapy (RIT) shortens the duration of the up-dosing phase to 7 days. However, considering that patients receiving RIT are exposed to the allergens during a much shorter period of time and thus may be at a greater risk of systemic reactions, RIT is currently underused, especially in children. This study investigated the utility of combination treatment with RIT plus 1 dose of pretreatment anti-IgE in children with respiratory allergies. Methods: In this retrospective study, we reviewed records of children with allergic rhinitis (AR) and/or allergic asthma (AA) sensitized to dust mite allergens receiving RIT+1 dose of pretreatment anti-IgE (the RIT group) or conventional immunotherapy (the CIT group) at our hospital from January 2020 to March 2021. Data such as visual analogue scale (VAS) scores, comprehensive symptom and medication score (CSMS), allergy blood test results, adverse reactions, compliance and cost were collected and analyzed. Results: 40 patients in the RIT group and 81 patients in the CIT group were included in this study. Both treatments were well tolerated and patients in the 2 treatment groups had comparable local and systemic reactions. Compared to CIT, RIT + anti-IgE combination led to significantly faster symptomatic improvement as demonstrated by significantly decreased VAS and CSMS starting as early as 1 month after AIT initiation (P<0.05). Nobody dropped out in the RIT group during the 1 year follow-up, while 11 out of 81 patients in the CIT group dropped out (loss rate 13.5%). Thus, the RIT group had a significantly higher compliance rate than the CIT group (P<0.05). Finally, the 2 treatment regimens had comparable cost per patient per injection (P> 0.05). Conclusions: RIT + 1 dose of pretreatment anti-IgE combination has practical advantages over CIT, including comparable safety, better compliance, and probably a faster onset of clinical efficacy at no additional cost, so it can be an useful regimen for the treatment of Chinese children with respiratory allergies.

The protective effects of nesfatin-1 in neurological dysfunction after spinal cord injury by inhibiting neuroinflammation.

AIMS: Spinal cord injury (SCI) is one of the most severe neurological diseases. However, there is still no effective treatment for it. Nesfatin, a precursor neuropeptide derived from nucleobindin 2 (NUCB2), has displayed a wide range of protective effects in different types of cells and tissue. However, the effects of nesfatin-1 in SCI have not been reported before. MATERIALS AND METHODS: A SCI model was established. The behavior of mice was assessed using the Basso, Beattie, and Bresnahan (BBB) assessment. RESULTS: Here, we report that the administration of nesfatin-1 improved neurological recovery in SCI mice by increasing BBB scores, reducing lesion area volume and spinal cord water content. Also, nesfatin-1 ameliorated oxidative stress by reducing reactive oxygen species (ROS) levels and increasing superoxide dismutase (SOD) activity. We also found that nesfatin-1 prevented neuronal apoptosis in SCI mice by reducing caspase 3 activity and the expression of Bax, as well as increasing B-cell lymphoma-2 (Bcl-2). Additionally, nesfatin-1 reduced the levels of interleukin 6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α). Nesfatin-1 also promoted microglia towards M2 polarization by increasing the marker CD206 but reducing CD16. Importantly, nesfatin-1 enhanced the phosphorylation of signal transducer and activator of transcription 1 (STAT1) but reduced the expression levels of toll-like receptor 4 (TLR4) and phosphorylated nuclear factor kappa-B p65 (p-NF-κB p65). CONCLUSION: Our findings imply that nesfatin-1 exerts neuroprotective actions in SCI by promoting the activation of M2 microglia, and its underlying mechanisms might be related to the activation of STAT1 and inhibition of the TLR4/NF-κB signaling pathway.

A Review of Spatter in Laser Powder Bed Fusion Additive Manufacturing: In Situ Detection, Generation, Effects, and Countermeasures.

Spatter is an inherent, unpreventable, and undesired phenomenon in laser powder bed fusion (L-PBF) additive manufacturing. Spatter behavior has an intrinsic correlation with the forming quality in L-PBF because it leads to metallurgical defects and the degradation of mechanical properties. This impact becomes more severe in the fabrication of large-sized parts during the multi-laser L-PBF process. Therefore, investigations of spatter generation and countermeasures have become more urgent. Although much research has provided insights into the melt pool, microstructure, and mechanical property, reviews of spatter in L-PBF are still limited. This work reviews the literature on the in situ detection, generation, effects, and countermeasures of spatter in L-PBF. It is expected to pave the way towards a novel generation of highly efficient and intelligent L-PBF systems.

Artificial neural network for cytocompatibility and antibacterial enhancement induced by femtosecond laser micro/nano structures.

The failure of orthopedic and dental implants is mainly caused by biomaterial-associated infections and poor osseointegration. Surface modification of biomedical materials plays a significant role in enhancing osseointegration and anti-bacterial infection. In this work, a non-linear relationship between the micro/nano surface structures and the femtosecond laser processing parameters was successfully established based on an artificial neural network. Then a controllable functional surface with silver nanoparticles (AgNPs) to was produced to improve the cytocompatibility and antibacterial properties of biomedical titanium alloy. The surface topography, wettability, and Ag+ release were carefully investigated. The effects of these characteristics on antibacterial activity and cytocompatibilty were also evaluated. Results show that the prepared surface is hydrophobic, which can prevent the burst release of Ag+ in the initial stage. The prepared surface also shows both good cytocompatibility toward the murine calvarial preosteoblasts MC3T3-E1 cells (derived from Mus musculus (mouse) calvaria) and good antibacterial effects against Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria, which is caused by the combined effect of appropriate micro/nano-structured feature and reasonable Ag+ release rate. We do not only clarify the antibacterial mechanism but also demonstrate the possibility of balancing the antibacterial and osteointegration-promoting properties by micro/nano-structures. The reported method offers an effective strategy for the patterned surface modification of implants.

Allergic Reactions After the Administration of COVID-19 Vaccines.

Background: Data on allergic reactions after the administration of coronavirus disease (COVID-19) vaccines are limited. Our aim is to analyze reports of allergic reactions after COVID-19 vaccine administration. Methods: The Vaccine Adverse Event Reporting System database was searched for reported allergic reactions after the administration of any of the COVID-19 vaccines from December 2020 to June 2021. After data mapping, the demographic and clinical characteristics of the reported cases were analyzed. Potential factors associated with anaphylaxis were evaluated using multivariable logistic regression models. Results: In total, 14,611 cases were reported. Most cases of allergic reactions comprised women (84.6%) and occurred after the first dose of the vaccine (63.6%). Patients who experienced anaphylaxis were younger (mean age 45.11 ± 5.6 vs. 47.01 ± 6.3 years, P < 0.001) and had a higher prevalence of a history of allergies, allergic rhinitis, asthma, and anaphylaxis than those who did not (P < 0.05). A history of allergies (odds ratio (OR) 1.632, 95% confidence interval (CI) 1.467-1.816, P < 0.001), asthma (OR 1.908, 95%CI 1.677-2.172, P < 0.001), and anaphylaxis (OR 7.164, 95%CI 3.504-14.646, P < 0.001) were potential risk factors for anaphylaxis. Among the 8,232 patients with reported outcomes, 16 died. Conclusions: Female predominance in allergic reaction cases after the receipt of COVID-19 vaccines was observed. Previous histories of allergies, asthma, or anaphylaxis were risk factors for anaphylaxis post-vaccination. People with these risk factors should be monitored more strictly after COVID-19 vaccination.