Iron Status, Thyroid Dysfunction, and Iron Deficiency Anemia: A Two-Sample Mendelian Randomization Study.

INTRODUCTION: Given the clinical association between thyroid dysfunction and iron deficiency anemia (IDA), as well as their shared association with iron status, this study aimed to investigate the causal relationship between iron status and thyroid dysfunction, while also examining the risk of IDA in relation to thyroid dysfunction. METHODS: A two-sample mendelian randomization (MR) study was conducted to identify the causal relationship of iron status on thyroid dysfunction, as well as thyroid dysfunction on IDA. Large-scale European population-based genome-wide association study databases were utilized (Genetics of Iron Status consortium, ThyroidOmics consortium, FinnGen consortium, and UK Biobank). Inverse variance-weighted (IVW) was used as the main analysis. In addition, we used weighted median and MR-Egger to enhance the robustness. Sensitivity analysis was conducted to evaluate the robustness of MR results. RESULTS: The IVW estimates did not reveal any significant causal relationship between serum iron status markers and thyroid dysfunction. However, a significant causal relationship was observed between hypothyroidism and IDA (odds ratio [OR] = 1.101, 95% confidence interval [CI] = 1.048-1.157, p < 0.001). Repeated analyses also demonstrated a similar trend (OR = 1.023, 95% CI = 1.011-1.035, p < 0.001). Sensitivity analysis supported that the MR estimates were robust. CONCLUSION: In our MR study, an upregulation of the hypothyroidism-associated gene was found to be significantly associated with an elevated risk of IDA in the European population. These findings may offer novel therapeutic insights for clinicians managing patients with hypothyroidism, IDA, or their comorbidities.

The role of integrin beta in schizophrenia: a preliminary exploration.

Integrins are transmembrane heterodimeric (αß) receptors that transduce mechanical signals between the extracellular milieu and the cell in a bidirectional manner. Extensive research has shown that the integrin beta (ß) family is widely expressed in the brain and that they control various aspects of brain development and function. Schizophrenia is a relatively common neurological disorder of unknown etiology and has been found to be closely related to neurodevelopment and neurochemicals in neuropathological studies of schizophrenia. Here, we review literature from recent years that shows that schizophrenia involves multiple signaling pathways related to neuronal migration, axon guidance, cell adhesion, and actin cytoskeleton dynamics, and that dysregulation of these processes affects the normal function of neurons and synapses. In fact, alterations in integrin ß structure, expression and signaling for neural circuits, cortex, and synapses are likely to be associated with schizophrenia. We explored several aspects of the possible association between integrin ß and schizophrenia in an attempt to demonstrate the role of integrin ß in schizophrenia, which may help to provide new insights into the study of the pathogenesis and treatment of schizophrenia.

Platelet-derived extracellular vesicles play an important role in platelet transfusion therapy.

Extracellular vesicles (EVs) contain the characteristics of their cell of origin and mediate cell-to-cell communication. Platelet-derived extracellular vesicles (PEVs) not only have procoagulant activity but also contain platelet-derived inflammatory factors (CD40L and mtDNA) that mediate inflammatory responses. Studies have shown that platelets are activated during storage to produce large amounts of PEVs, which may have implications for platelet transfusion therapy. Compared to platelets, PEVs have a longer storage time and greater procoagulant activity, making them an ideal alternative to platelets. This review describes the reasons and mechanisms by which PEVs may have a role in blood transfusion therapy.

What is the context?Platelet transfusion is a treatment that can be effective in preventing bleeding and reducing the amount of bleeding. However, platelet transfusion may cause some unsatisfactory effects for patients, such as adverse transfusion reactions and poor prognosis in cancer patients. These benefits and harms caused by platelet transfusion may be related to PEVs. With the prolongation of storage time during the shelf life of platelets, PEVs were continuously released and the therapeutic effect of platelet components seems to get worse.What is new?This article not only reviews the evidence for PEVs plays a role in blood transfusion therapy but also introduces the mechanism of PEVs in platelet storage lesion and the common methods of isolation and characterization of PEVs.What is the impact?It is necessary to improve the method of isolation and purification of PEVs, to increase the purity of PEVs isolation, and to further demonstrate the potential of PEVs to replace platelets. Further research into the mechanisms by which platelets and PEVs affect the prognosis of cancer patients is required.

Associations of Postoperative Hemoglobin Level and Clinical Outcomes in Patients Undergoing Mitral Valve Surgery.

BACKGROUND: Postoperative hemoglobin could indicate useful information for transfusion practices. The aim of this study was to investigate the association of optimal hemoglobin level and clinical outcomes after mitral valve surgery (MVS). METHODS: This investigation was a multicenter observational cohort study including 1,518 patients undergoing mitral valve surgery from 2016 through 2018. Patients were separated into six predefined groups based on initial postoperative hemoglobin (< 7.5 g/dL, 7.5 - 8.4 g/dL, 8.5 - 9.4 g/dL, 9.5 - 10.4 g/dL, 10.5 - 11.4 g/dL, ≥ 11.5 g/dL). Multivariable regression analysis was used to adjust laboratory results and surgical features of patients to evaluate the relationships between initial hemoglobin after MVS and clinical outcomes. RESULTS: Patients with initial postoperative hemoglobin below 7.5 g/dL had longer length of stays [mean (95% confidence interval [CI]), 1.9 (1.093 - 1.367)] in comparison with the reference group of 9.5 - 10.4 g/dL. Similarly, for those with hemoglobin below 7.5 g/dL, the odds (95% CI) for secondary outcomes included myocardial infraction 11.801 (1.353 - 22.966) and thrombosis 5.113 (1.340 - 9.508). However, for clinical outcomes, there was no significant difference between the five groups with hemoglobin greater than 7.5 g/dL. CONCLUSIONS: In patients after MVS, initial postoperative hemoglobin values below 7.5 g/dL was associated with worse outcomes compared to other values. Given similar outcomes between hemoglobin more than 7.5 g/dL groups, targeting treatment to an initial postoperative hemoglobin value at the lower value may be more desirable.

Platelet supernatant with longer storage inhibits tumor cell growth.

BACKGROUND: Platelet transfusion is an essential supportive treatment for cancer patients. Platelets promote metastasis, but their role in tumor growth remains controversial. This study aimed to explore the impact of apheresis platelet supernatants of different storage periods on tumor cell growth, optimize blood transfusion timing, and provide a reference for reducing the risks of platelet transfusion in cancer patients. METHODS: Eight human tumor cell lines, including HepG2, HuH7, SMMC-7721, HeLa, HCT116, MCF-7, K562, and Jurkat were cultured. After culturing the platelet supernatant of days 0, 3, 5, and 7 with tumor cells, counting kit 8 (CCK-8), scratch assay, and propidium iodide (PI) were used to evaluate cell proliferation, migration, and cell cycle, respectively. Metabolomics analysis was performed to confirm whether differential metabolites produced during platelet storage are involved in the cancer pathway. RESULTS: Platelet supernatants inhibit tumor cell proliferation by blocking the cell cycle at the G0/G1 phase, and their inhibitory effect increases with storage time. However, platelets promote tumor cells to form cytoskeletal connections, thereby promoting migration. Besides, metabonomics analysis of platelet supernatants during different storage periods reveals that upregulated differential metabolites are involved in cancer-related pathways. CONCLUSION: The role of platelets in tumor cells is two-sided, that is, they inhibit proliferation while promoting migration. Therefore, additional in-depth studies on the appropriate timing of platelet transfusion are necessary.

The role of CD38 in HIV infection.

The widely-expressed molecule CD38 is a single-stranded type II transmembrane glycoprotein that is mainly involved in regulating the differentiation and activation state of the cell. CD38 has broad and complex functions, including enzymatic activity, intercellular signal transduction, cell activation, cytokine production, receptor function and adhesion activity, and it plays an important role in the physiological and pathological processes of many diseases. Many studies have shown that CD38 is related to the occurrence and development of HIV infection, and CD38 may regulate its progression through different mechanisms. Therefore, investigating the role of CD38 in HIV infection and the potential signaling pathways that are involved may provide a new perspective on potential treatments for HIV infection. In the present review, the current understanding of the roles CD38 plays in HIV infection are summarized. In addition, the specific role of CD38 in the process of HIV infection of human CD4+ T lymphocytes is also discussed.

Diagnostic and prognostic values of circular RNAs for lung cancer: a meta-analysis.

Circular RNAs (circRNAs) may serve as potential biomarkers for patients with lung cancer. The aim of this meta-analysis was to analyse the diagnostic, prognostic and clinicopathological values of circRNAs in lung cancer patients. A systematic search of PubMed, Embase, Web of Science, Scopus and the Cochrane Library databases was performed for relevant articles from inception to 29 January 2020. Pooled parameters including sensitivity, specificity and area under the curve (AUC) were used to assess the diagnostic performance, HRs and 95% CIs were used to evaluate overall survival (OS) and ORs were used to estimate clinicopathological parameters. 52 studies from 45 articles were enrolled in this study, including 17 on diagnosis and 35 on prognosis. For diagnostic values, circRNAs could discriminate lung cancer patients from the controls, with AUC of 0.83 (95% CI: 0.79 to 0.86), a relatively high sensitivity of 0.77 (95% CI: 0.73 to 0.81) and specificity of 0.75 (95% CI: 0.71 to 0.79). For prognostic significances, overexpression of 23 upregulated circRNAs was relevant to a poor prognosis (OS: HR=2.21, 95% CI: 1.96 to 2.49, p<0.001), and overexpression of 9 downregulated circRNAs was correlated with a favourable prognosis (OS: HR=0.62, 95% CI: 0.53 to 0.73, p<0.001). As for clinicopathological parameters, high expression of 23 upregulated circRNAs was associated with unfavourable clinicopathological features while 9 downregulated circRNAs proved the contrary. In conclusion, this study confirmed that circRNAs might serve as important biomarkers for diagnostic and prognostic values of lung cancer.

[Effect of red blood cell storage duration on the clinical effect of exchange transfusion and internal environment in neonates with hyperbilirubinemia].

OBJECTIVE: To study the effect of red blood cell (RBC) storage duration on the clinical effect of exchange transfusion (ET) and internal environment in neonates with hyperbilirubinemia. METHODS: A retrospective analysis was performed for the clinical data of 135 neonates with hyperbilirubinemia who received ET between January 2015 and August 2018. According to RBC storage duration, the neonates were divided into short-term storage group (RBCs were stored for ≤7 days) with 56 neonates and long-term storage group (RBCs were stored for >7 days) with 79 neonates. The two groups were compared in terms of serum total bilirubin (TBIL) level and the rate of TBIL reduction at 0 and 12 hours after ET, as well as the duration of continued phototherapy and rate of repeated ET. Routine blood test parameters, electrolytes, blood glucose, and blood gas parameters were measured before ET and at 0 hour after ET. RESULTS: At 0 hour after ET, there were no significant differences in the TBIL level and the rate of TBIL reduction between the two groups (P>0.05). At 12 hours after ET, the long-term storage group had a significantly higher TBIL level and a significantly lower rate of TBIL reduction than the short-term storage group (P<0.01). The long-term storage group had a significantly longer duration of continued phototherapy after ET than the short-term storage group (P<0.05). Compared with the short-term storage group, the long-term storage group had significantly higher incidence rates of ET-related complications, including hyponatremia, hyperkalemia, and metabolic acidosis (P<0.05). CONCLUSIONS: The use of RBCs with a storage duration of >7 days in ET for neonates with hyperbilirubinemia does not affect the immediate effect of ET, but these neonates tend to have a poor outcome after continued phototherapy and high risk of hyponatremia, hyperkalemia, and metabolic acidosis.

Neonatal alloimmune thrombocytopenia caused by anti-HPA antibodies in pregnant Chinese women: a study protocol for a multicentre, prospective cohort trial.

BACKGROUND: Neonatal alloimmune thrombocytopenia (NAIT), caused by maternal antibodies raised against alloantigens carried on foetal platelets, is a very common haematological abnormality in newborns worldwide. However, baseline data on NAIT in China are lacking. Therefore, this study seeks to explore the incidence of alloantibody against the human platelet antigen (HPA) in pregnant women and its associations with NAIT in China. METHODS: A multicentre, prospective cohort study design will be used, and 55,497 pregnant women will be recruited for the first screening of the anti-HPA antibody at 12 to 28 weeks of gestational age. Subjects who are positive in the first screening for the anti-HPA antibody will be included in the exposure group. Re-tests of the antibody titre, antigen-specificity and genotyping of HPA and HLA will be conducted during admission. A ratio of 1:1 paired individuals with the same ethnicity and parity but testing negative for the anti-HPA antibody will be randomly selected to be included in the non-exposure group. NAIT will be diagnosed in the newborns on day one of the birth. The HPA of the neonates in the exposure group will also be genotyped by sequencing. Associations of maternal HLA with the occurrence of the anti-HPA antibody and correlation of the severity of NAIT with the titre of the anti-HPA antibody will be further analysed. DISCUSSION: The study is expected to provide baseline data on NAIT in China. Besides, we hope to find out a population who expresses particular HLA molecules has significant higher risk of HPA alloimmunization in Chinese individuals. We also hope to find a Chinese-specific cut-off antibody titre for the prediction of the severity of NAIT and to provide a means to evaluate the necessity of antenatal treatment. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02934906 (date registered: 13.10.2016).

Notch Receptor-Ligand Engagement Maintains Hematopoietic Stem Cell Quiescence and Niche Retention.

Notch is long recognized as a signaling molecule important for stem cell self-renewal and fate determination. Here, we reveal a novel adhesive role of Notch-ligand engagement in hematopoietic stem and progenitor cells (HSPCs). Using mice with conditional loss of O-fucosylglycans on Notch EGF-like repeats important for the binding of Notch ligands, we report that HSPCs with faulty ligand binding ability display enhanced cycling accompanied by increased egress from the marrow, a phenotype mainly attributed to their reduced adhesion to Notch ligand-expressing stromal cells and osteoblastic cells and their altered occupation in osteoblastic niches. Adhesion to Notch ligand-bearing osteoblastic or stromal cells inhibits wild type but not O-fucosylglycan-deficient HSPC cycling, independent of RBP-JK -mediated canonical Notch signaling. Furthermore, Notch-ligand neutralizing antibodies induce RBP-JK -independent HSPC egress and enhanced HSPC mobilization. We, therefore, conclude that Notch receptor-ligand engagement controls HSPC quiescence and retention in the marrow niche that is dependent on O-fucosylglycans on Notch.

Molecular dysfunctions in acute rejection after renal transplantation revealed by integrated analysis of transcription factor, microRNA and long noncoding RNA.

Acute rejection remains a problem in renal transplantation. To further illustrate the mechanism of rejection, we integrated protein array-based proteomics and RNA microarray-based genomics to investigate the transcription factor, microRNA and long noncoding RNA of biopsies of three patients with acute rejections and a control group. 99 transcription factors were identified in acute rejection biopsies compared to normal renal tissue. We correlated transcription factor data with microRNA and long noncoding RNA data sets and reported the expression of 5 transcription factors (AP-1, AP-4, STATx, c-Myc and p53), 12 miRNAs and 32 lncRNAs in acute rejection biopsies. Pathway analysis demonstrated that over-presentation of transcription factor pathway plays a critical role in acute rejection. This is the first study to comprehensively report the acute rejection transcription factor pathway. Integrative analysis of the transcription factor, microRNA and long noncoding RNA provided an expansive view of molecular signaling pathways in acute rejection after renal transplantation.

[Retracted] miR­133b induces chemoresistance of osteosarcoma cells to cisplatin treatment by promoting cell death, migration and invasion.

[This retracts the article DOI: 10.3892/ol.2017.7432.].

[Retracted] miR­34a is downregulated in human osteosarcoma stem­like cells and promotes invasion, tumorigenic ability and self­renewal capacity.

Following the publication of this paper, it was drawn to the Editor's attention by a concerned reader that certain of the Transwell cell invasion assay data shown in Fig. 4B on p. 1635 were strikingly similar to data appearing in different form in other articles written by different authors at different research institutes, which had either already been published or were submitted at around the same time. Owing to the fact that the contentious data in the above article had already been published prior to its submission to Molecular Medicine Reports, the Editor has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused. [Molecular Medicine Reports 15: 1631­1637, 2017; DOI: 10.3892/mmr.2017.6187].

Fully human anti-B7-H3 recombinant antibodies inhibited tumor growth by increasing T cell infiltration.

Mortality due to malignant tumors is one of the major factors affecting the life expectancy of the global population. Therapeutic antibodies are a cutting-edge treatment method for restricting tumor growth. B7-H3 is highly expressed in tumor tissues, but rarely in normal tissues. B7-H3 is closely associated with poor prognosis in patients with tumors. B7-H3 is an important target for antitumor therapy. In this study, the fully human anti-B7H3 single-chain antibodies (scFvs) were isolated and screened from the fully human phage immune library with B7H3 as the target. The antibodies screened from a fully human phage library had low immunogenicity and high affinity, which was more beneficial for clinical application. Leveraging B7-H3 scFvs as a foundation, we constructed two distinct recombinant antibody formats, scFv-Fc and IgG1, characterized by elevated affinity and a prolonged half-life. The results demonstrated that the recombinant antibodies had high specificity and affinity for the B7-H3 antigen and inhibited tumor cell growth by enhancing the ADCC. After treatment with anti-B7H3 recombinant antibody, the number of infiltrating T cells in the tumor increased and the secretion of IFN- γ by infiltrating T cells increased in vivo. Additionally, the use of pleural fluid samples obtained from tumor-afflicted patients revealed the ability of anti-B7-H3 recombinant antibodies to reverse CD8+ T cell exhaustion. In summary, we screened the fully human anti-B7H3 recombinant antibodies with specificity and high affinity that increase immune cell infiltration and IFN-γ secretion, thereby inhibiting tumor cell growth to a certain extent. This finding provides a theoretical basis for the development of therapeutic tumor antibodies and could help promote further development of antibody-based drugs.

Protein O-fucosyltransferase 1 (Pofut1) regulates lymphoid and myeloid homeostasis through modulation of Notch receptor ligand interactions.

Notch signaling is essential for lymphocyte development and is also implicated in myelopoiesis. Notch receptors are modified by O-fucosylation catalyzed by protein O-fucosyltransferase 1 (Pofut1). Fringe enzymes add N-acetylglucosamine to O-fucose and modify Notch signaling by altering the sensitivity of Notch receptors to Notch ligands. To address physiologic functions in hematopoiesis of Notch modified by O-fucose glycans, we examined mice with inducible inactivation of Pofut1 using Mx-Cre. These mice exhibited a reduction in T lymphopoiesis and in the production of marginal-zone B cells, in addition to myeloid hyperplasia. Restoration of Notch1 signaling rescued T lymphopoiesis and the marrow myeloid hyperplasia. After marrow transfer, both cell-autonomous and environmental cues were found to contribute to lymphoid developmental defects and myeloid hyperplasia in Pofut1-deleted mice. Although Pofut1 deficiency slightly decreased cell surface expression of Notch1 and Notch2, it completely abrogated the binding of Notch receptors with Delta-like Notch ligands and suppressed downstream Notch target activation, indicating that O-fucose glycans are critical for efficient Notch-ligand binding that transduce Notch signals. The combined data support a key role for the O-fucose glycans generated by Pofut1 in Notch regulation of hematopoietic homeostasis through modulation of Notch-ligand interactions.

Impacts of cigarette smoking on blood circulation: do we need a new approach to blood donor selection?

Smoking is a major public health problem and is considered the leading cause of preventable death worldwide. Gas-phase smoke carries bioactive substances and toxic compounds, affecting human health and reducing life spans. The negative effects of smoking on red blood cell (RBC) quality include destroying RBCs and increasing carboxy hemoglobin (COHb). Smoking increases the concentrations of heavy metals such as cadmium (Cd) and lead (Pb) in the blood. Moreover, tobacco smoking has been found to be associated with heightened platelet (PLT)-dependent thrombin level which will induce a prothrombotic state. Smoking may affect the blood circulation of donors, and subsequently the blood components, and ultimately the recipients of transfusion. Nevertheless, there are no restrictions on smoking for volunteer blood donor screenings currently. We reviewed the articles about the influence of smoking on smokers' blood circulation as well as the impact of donated blood products on transfusion when these smokers act as blood donors. We aim to attract blood collection centers' attention to strengthen the management of blood donors who smoke, avoiding their use in massive transfusion protocol and susceptible recipients, especially pediatric ones.

Application of tumor-educated platelets as new fluid biopsy markers in various tumors.

The incidence of malignant tumors is increasing year by year. Early detection and diagnosis of malignant tumors can improve the prognosis of patients and prolong their life. Pathological biopsy is the current gold standard for diagnosis, but the results of pathological biopsy are affected by the sampling site and cannot fully reflect the nature of the disease. Moreover, the invasive nature of pathological biopsy limits repeated detection. Liquid biopsies are non-invasive and can be used for early detection and monitoring of tumors, which considered to represent a promising tool. Platelets make themselves to be one of the richest liquid biopsy sources by the capacity to take up proteins and nucleic acids and alter their megakaryocyte-derived transcripts and proteins in response to external signals, which are called tumor-educated platelets (TEPs). In this article, we will review the application of tumor-educated platelets in various malignancies (nasopharyngeal carcinoma, prostate cancer, lung cancer, glioblastoma, colorectal cancer, pancreas cancer, ovarian cancer, sarcoma, breast cancer and hepatocellular carcinoma) and provide theoretical basis for the research of TEPs in tumor diagnosis, monitoring and treatment.

[Effects of Platelet-Rich Plasma on Macrophage Phenotype and Its Influencing Factors].

OBJECTIVE: To evaluate the effects of platelet-rich plasma (PRP) supernatants with different activation methods and storage time on human monocyte-derived macrophages phenotype and explore the possible mechanism. METHODS: Human monocyte-derived macrophages were cultured in vitro with PRP or activated PRP supernatants activated with different activators. The expression of marker molecules on the surface of macrophages was detected by flow cytometry, and the concentration of growth factors in PRP supernatants was detected by ELISA. RESULTS: After 24 h of coculture, the expression level of CD86 in macrophages stimulated by PRP supernatant (thrombin and Cacl2 activated) was significantly higher than that by PRP group (P<0.05), and the expression of CD163 in macrophages was increased by Cacl2 activated PRP supernatant. Compared with different activator groups, the expression of CD163 in macrophages of Cacl2 activated group was significantly higher than that of thrombin and ADP groups (P<0.05). ELISA results showed that the concentrations of FGF (P<0.001) and EGF (P<0.05) in the supernatant of PRP stored at -80 ℃ for more than 20 months and 10-20 months were significantly higher than those in the group stored at less than 10 months after Cacl2 activation, and the expressions of CD86 (P<0.01), CD163 (P<0.001) and CD206 (P<0.001) in macrophages cocultured with the supernatant of the two groups were significantly increased. CONCLUSION: PRP activated by different activators has different effects on the phenotype of macrophages. Meanwhile, the storage time will also affect the growth factor concentration and effect of PRP.

Identification of risk factors for infection after mitral valve surgery through machine learning approaches.

Background: Selecting features related to postoperative infection following cardiac surgery was highly valuable for effective intervention. We used machine learning methods to identify critical perioperative infection-related variables after mitral valve surgery and construct a prediction model. Methods: Participants comprised 1223 patients who underwent cardiac valvular surgery at eight large centers in China. The ninety-one demographic and perioperative parameters were collected. Random forest (RF) and least absolute shrinkage and selection operator (LASSO) techniques were used to identify postoperative infection-related variables; the Venn diagram determined overlapping variables. The following ML methods: random forest (RF), extreme gradient boosting (XGBoost), Support Vector Machine (SVM), Gradient Boosting Decision Tree (GBDT), AdaBoost, Naive Bayesian (NB), Logistic Regression (LogicR), Neural Networks (nnet) and artificial neural network (ANN) were developed to construct the models. We constructed receiver operating characteristic (ROC) curves and the area under the ROC curve (AUC) was calculated to evaluate model performance. Results: We identified 47 and 35 variables with RF and LASSO, respectively. Twenty-one overlapping variables were finally selected for model construction: age, weight, hospital stay, total red blood cell (RBC) and total fresh frozen plasma (FFP) transfusions, New York Heart Association (NYHA) class, preoperative creatinine, left ventricular ejection fraction (LVEF), RBC count, platelet (PLT) count, prothrombin time, intraoperative autologous blood, total output, total input, aortic cross-clamp (ACC) time, postoperative white blood cell (WBC) count, aspartate aminotransferase (AST), alanine aminotransferase (ALT), PLT count, hemoglobin (Hb), and LVEF. The prediction models for infection after mitral valve surgery were established based on these variables, and they all showed excellent discrimination performance in the test set (AUC > 0.79). Conclusions: Key features selected by machine learning methods can accurately predict infection after mitral valve surgery, guiding physicians in taking appropriate preventive measures and diminishing the infection risk.

The role of ClpP in protein expression of Streptococcus pneumoniae.

Previous reports suggest that ClpP proteolytic activity is important not only for cell physiology but also for regulation of virulence properties of Streptococcus pneumoniae (S. pneumoniae). In order to get a more comprehensive picture of the role of ClpP protease on protein expression in S. pneumoniae D39 and how it relates to physiology and virulence, a clpP mutant strain was constructed in S. pneumoniae D39, and global proteome expression was studied by 2-dimensional electrophoresis and matrix-assisted laser desorption-ionization-time of flight mass spectrometry. We report here that clpP deletion affects the expression of proteins which are involved in the general stress response, nucleotide metabolism, energy metabolism, and proteins metabolism. These provide clues for understanding the role of ClpP in the physiology and pathogenesis of pneumococcus.