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Patients with stable coronary artery disease (CAD) are at an increased risk of acute myocardial infarction (AMI), particularly among older individuals. Developing a reliable model to predict AMI occurrence in these patients holds the potential to expedite early diagnosis and intervention. This study is aimed at establishing a circulating amino acid‐assisted model, incorporating amino acid profiles alongside clinical variables, to predict AMI risk. A cohort of 874 CAD patients from two independent centers was analyzed. Plasma amino acid levels were quantified using liquid chromatography tandem mass spectrometry (LC‐MS/MS) employing a targeted metabolomics approach. This methodology incorporated 13C isotope‐labeled internal standards for precise quantification of 27 amino acids. Univariate logistic regression was applied to identify differentially expressed amino acids that distinguished between stable CAD and AMI patients. To assess prediction performance, receiver operating characteristic (ROC) curve and nomogram analyses were utilized. Five amino acids—lysine, methionine, tryptophan, tyrosine, and N6‐trimethyllysine—emerged as potential biomarkers (p < 0.05), exhibiting significant differences in their expression levels across the two centers when comparing stable CAD with AMI patients. For AMI risk prediction, the base model, utilizing 12 clinical variables, achieved areas under the curve (AUC) of 0.7387 in the discovery phase (n = 623) and 0.8205 in the external validation set (n = 251). Notably, the integration of these five amino acids into the prediction model significantly enhanced its performance, increasing the AUC to 0.7651 in the discovery phase (Delong's test, p = 1.43e‐02) and to 0.8958 in the validation set (Delong's test, p = 8.91e‐03). In conclusion, the circulating amino acid‐assisted model effectively enhances the prediction of AMI risk among CAD patients, indicating its potential clinical utility in facilitating early detection and intervention. [ABSTRACT FROM AUTHOR]

Abstract Retroviral transduction involves integrase-dependent linkage of viral and host DNA that leaves an intermediate that requires post-integration repair (PIR). We and others proposed that PIR hijacks the host cell double-strand DNA break (DSB) repair pathways. Nevertheless, the geometry of retroviral DNA integration differs considerably from that of DSB repair and so the precise role of host-cell mechanisms in PIR remains unclear. In the current study, we found that the Nijmegen breakage syndrome 1 protein (NBS1), an early sensor of DSBs, associates with HIV-1 DNA, recruits the ataxia telangiectasia-mutated (ATM) kinase, promotes stable retroviral transduction, mediates efficient integration of viral DNA and blocks integrase-dependent apoptosis that can arise from unrepaired viral-host DNA linkages. Moreover, we demonstrate that the ATM kinase, recruited by NBS1, is itself required for efficient retroviral transduction. Surprisingly, recruitment of the ATR kinase, which in the context of DSB requires both NBS1 and ATM, proceeds independently of these two proteins. A model is proposed emphasizing similarities and differences between PIR and DSB repair. Differences between the pathways may eventually allow strategies to block PIR while still allowing DSB repair.

Metabolomics offers a noninvasive methodology to identify metabolic markers for pathogenesis and diagnosis of diseases. This work aimed to characterize circulating metabolic signatures of benign thyroid nodule (BTN) and papillary thyroid carcinoma (PTC) via serum‐plasma matched metabolomics. A cohort of 1,540 serum‐plasma matched samples and 114 tissues were obtained from healthy volunteers, BTN and PTC patients enrolled from 6 independent centers. Untargeted metabolomics was determined by liquid chromatography‐quadrupole time‐of‐flight mass spectrometric and multivariate statistical analyses. The use of serum‐plasma matched samples afforded a broad‐scope detection of 1,570 metabolic features. Metabolic phenotypes revealed significant pattern differences for healthy versus BTN and healthy versus PTC. Perturbed metabolic pathways related mainly to amino acid and lipid metabolism. It is worth noting that, BTN and PTC showed no significant differences but rather overlap in circulating metabolic signatures, and this observation was replicated in all study centers. For differential diagnosis of healthy versus thyroid nodules (BTN + PTC), a panel of 6 metabolic markers, namely myo‐inositol, α‐N‐phenylacetyl‐L‐glutamine, proline betaine, L‐glutamic acid, LysoPC(18:0) and LysoPC(18:1) provided area under the curve of 97.68% in the discovery phase and predictive accuracies of 84.78–98.18% in the 4 validation centers. Taken together, serum‐plasma matched metabolomics showed significant differences in circulating metabolites for healthy versus nodules but not for BTN versus PTC. Our results highlight the true metabolic nature of thyroid nodules, and potentially decrease overtreatment that exposes patients to unnecessary risks. What's new? When thyroid nodules are classified "indeterminate," is it better to wait and see, or take out the thyroid? Usually, doctors remove the thyroid, resulting in a lifetime of levothyroxine replacement, yet most often the nodules are not cancerous. Here, the authors investigated whether metabolic profile could give a more accurate prediction of whether a thyroid nodule is cancerous. They tested healthy patients, those with benign nodules, and those with papillary thyroid carcinoma. Healthy patients showed distinct differences from those with benign nodules and those with carcinomas, while significant overlap was observed between circulating metabolites from BTN and PTC patients. [ABSTRACT FROM AUTHOR]

Three new lupane-triterpenoids (1–3) along with six known compounds (4–9) were isolated from the ethanolic extract of whole plant of Potentilla discolor Bunge. The structures of Compounds 1–3 were established by extensive 1D and 2D NMR together with other spectrum analysis, indicating that their C-27 positions were highly oxygenated, which were rarely found in nature. Their in vitro anti-proliferative activities against HepG-2, MCF-7 and T-84 cell lines were evaluated by Cell Counting Kit-8 (CCK-8) assay, and the results showed different activities for three cell lines with IC50 values ranging from 17.84 to 40.64 μM. In addition, the results from Hoechst 33258 and AO/EB staining as well as annexinV-FITC assays exhibited Compound 1 caused a markedly increased HepG-2 cellular apoptosis in a dose-dependent manner. The further mechanisms of Compound 1-induced cellular apoptosis were confirmed that 1 induced the production of ROS and the alteration of pro- and anti-apoptotic proteins, which led to the dysfunction of mitochondria and activation of caspase-9 and caspase-3 and finally caused cellular apoptosis. These results would be useful in search for new potential antitumor agents and for developing semisynthetic lupane-triterpenoid derivatives with high antitumor activity. [ABSTRACT FROM AUTHOR]

The annealing behaviour of 400 keV Er ions at a fluence of 2×1015 cm-2 implanted into silicon-on-insulator (SOI) samples is investigated by Rutherford backscattering spectrometry of 2.1 MeV He2+ ions with a multiple scattering model. It is found that the damage close to the SOI surface is almost removed after being annealed in O2 and N2 atmospheres, successively, at 900 °C, and that only a small number of the Er atoms segregated to the surface of the SOI sample, whereas a large number of Er atoms diffused to a deeper position because of the affinity of Er for oxygen. For the SOI sample co-implanted with Er and O ions, there is no evident outdiffusion of Er atoms to the SOI surface after being annealed in N2 atmosphere at 900 °C. [ABSTRACT FROM AUTHOR]

We investigated the effect of spin-orbit coupling on magnetoresistance in nonmagnetic organic semiconductors. A Lorentz-type magnetoresistance is obtained from spin-orbit coupling-dependent spin precession under the condition of a space-charge-limited current. The magnetoresistance depends on the initial spin orientation of the electron with respect to the hole in electron-hole pairs, and the increasing spin-orbit coupling slows down the change in magnetoresistance with magnetic field. The field dependence, the sign and the saturation value of the magnetoresistance are composite effects of recombination and dissociation rate constants of singlet and triplet electron-hole pairs. The simulated magnetoresistance shows good consistency with the experimental results. [ABSTRACT FROM AUTHOR]

As a classic herbal prescription, Huanglian Jiedu Decoction (HLJDD) exhibits positive effects against cardiac dysfunction. However, its cardioprotective effects and potential mechanism(s) of action still need to be systematically investigated. This study aimed to reveal the underlying therapeutic mechanism of HLJDD on transverse aortic constriction (TAC)-induced pathological cardiac hypertrophy and remodeling. TAC-induced cardiac hypertrophy and remodeling mice model was established to evaluate the therapeutic effects of HLJDD. Serum untargeted metabolomics and lipidomic profiling were performed using ultra-performance liquid chromatography quadrupole-time-of-flight mass spectrometry coupled with multivariate statistical analyses. Oral administration of HLJDD (2.5 g/kg/day, 5.0 g/kg/day) significantly improved the heart morphology, enhanced the heart function, and alleviated the accumulation of fibrosis in the interstitial space and the infiltration of inflammatory cells in TAC-stimulated mice. Serum untargeted metabolomics analysis showed that significant alterations were observed in metabolic signatures between the TAC-model and sham group. Principal component analysis and orthogonal partial least-squares discriminant analysis screened 59 differential metabolic features and 13 metabolites were identified. The disturbed metabolic pathways in TAC group mainly related to lipid metabolism. Further serum lipidomic profiling showed that most lipids including cholesterol esters, ceramides, glycerides, fatty acids and phospholipids were decreased in TAC group and these alterations were reversed after HLJDD intervention. HLJDD alleviates TAC-induced pathological cardiac hypertrophy and remodeling, and its potential therapeutic mechanism involves the regulation of lipid metabolism. Image 1 [ABSTRACT FROM AUTHOR]

Aim: To compare the efficacy of vitrectomy combined with air or silicone oil in the treatment of idiopathic macular hole (IMH)., Methods: According to the results of high-definition optical coherence tomography (HD-OCT), 75 cases (75 eyes) of IMH in stage II-IV (Gass stage) in the General Hospital of Chinese PLA from January 2017 to December 2019 were collected for this retrospective study. The best corrected visual acuity (BCVA) and minimum diameter of IMH (MMHD) were measured. Eyes underwent vitrectomy combined with internal limiting membrane peeling operation, and were divided into disinfection air group (30 eyes) and silicone oil group (45 eyes) according to the intraocular tamponade. For MMHD≤400 µm (MMHD1), there were 23 eyes in air group and 16 eyes in silicone oil group. For MMHD2>400 µm (MMHD2), there were 7 eyes in air group and 29 eyes in silicone oil group. One month after surgery, the closure rates of IMH and BCVA were compared and analyzed. According to HD-OCT, the closure shape was graded with A (bridge closure) and B (good closure)., Results: The closure rates of air group and silicone oil group were 86.67% and 95.56% respectively with no significant difference ( P >0.05); For MMHD1, those of air group and silicone oil group were 95.65% and 100% respectively with no significant difference ( P >0.05); For MMHD2, those of air group and silicone oil group were 57.14% and 93.10% respectively, and those of the silicone oil group were higher than the air group ( P <0.05). There was no significant difference in the closure shape grade between MMHD1 air group and silicone oil group ( P >0.05). The proportion of Grade B in MMHD2 silicone oil group was higher than that in the air group ( P <0.05). BCVA of each group after operation was better than that before operation, and there was no significant difference between air group and silicone oil group. While among them, MMHD1 air group was better than silicone oil group ( P <0.05), and there was no significant difference between MMHD2 air group and silicone oil group ( P >0.05)., Conclusion: For smaller IMH (≤400 µm), the efficacy of vitrectomy combined with air should be considered better than silicone oil; for larger IMH (>400 µm), the efficacy of silicone oil may be better than air., (International Journal of Ophthalmology Press.)

APOBEC3G (A3G), a member of cytidine deaminase family, has potent anti-human immunodeficiency virus type 1 (HIV-1) activity. It has been demonstrated that alpha interferon (IFN-alpha) can significantly enhance the expression of A3G in human primary resting CD4(+) T-cells, macrophages and primary hepatocytes, subsequently decreasing their viral susceptibility. Plasmacytoid dendritic cells (pDCs) are key effectors in innate host immunity, mediating adaptive immune responses and stimulating IFN-alpha production in reaction to various stimuli. In this report, we demonstrate that IFN-alpha, either exogenously added to- or endogenously secreted by pDCs, can enhance the expression of A3G and its family members such as A3A, A3C and A3F. We have also shown that IFN-alpha can inhibit HIV-1 expression in pDCs. This inhibitory effect could be countered by addition of an A3G-specific short interfering RNA, indicating that IFN-alpha-induced A3G plays a key role in mediating pDCs response to HIV-1. Given the central role played by pDCs in orchestrating the IFN-alpha/A3G intercellular network and intracellular signal pathway, our data indicate that pDCs themselves are also protected by an IFN-alpha/A3G-mediated innate immunity barrier from HIV-1 infection.

The interferon (IFN) system, including various IFNs and IFN-inducible gene products, is well known for its potent innate immunity against wide-range viruses. Recently, a family of cytidine deaminases, functioning as another innate immunity against retroviral infection, has been identified. However, its regulation remains largely unknown. In this report, we demonstrate that through a regular IFN-alpha/beta signal transduction pathway, IFN-alpha can significantly enhance the expression of apolipoprotein B mRNA-editing enzyme-catalytic polypeptide-like 3G (APOBEC3G) in human primary resting but not activated CD4 T cells and the amounts of APOBEC3G associated with a low molecular mass. Interestingly, short-time treatments of newly infected resting CD4 T cells with IFN-alpha will significantly inactivate human immunodeficiency virus type 1 (HIV-1) at its early stage. This inhibition can be counteracted by APOBEC3G-specific short interfering RNA, indicating that IFN-alpha-induced APOBEC3G plays a key role in mediating this anti-HIV-1 process. Our data suggest that APOBEC3G is also a member of the IFN system, at least in resting CD4 T cells. Given that the IFN-alpha/APOBEC3G pathway has potent anti-HIV-1 capability in resting CD4 T cells, augmentation of this innate immunity barrier could prevent residual HIV-1 replication in its native reservoir in the post-highly active antiretroviral therapy era.

Dendritic cells (DCs) are potent antigen-presenting cells, and their physiological localization in tissues that interact with the external environment is important as a first barrier against pathogens such as human immunodeficiency virus type I (HIV-1). Several models have been proposed to explain the possible role of DCs as a reservoir for HIV-1 in patients on virally suppressive highly active antiretroviral therapy (HAART). However, the low yield of cell isolates has made this evaluation a difficult task. The present study analyzes whether peripheral blood DCs from HIV-1-infected individuals on virally suppressive HAART, with plasma HIV-1 RNA levels of less than 50 copies/ml, carry either HIV-1 provirus and/or HIV-1 virions. Peripheral blood DCs were isolated from a cohort of 10 HIV-1-seropositive men taking suppressive HAART. In five patients, plasmacytoid and myeloid dendritic cells were isolated to attempt to identify their respective roles in HIV-1 residual disease. Viral out-growth assays were performed in vitro, as well as gag and R/U5 polymerase chain reaction (PCR) amplification of viral RNA and DNA, respectively, from DC and peripheral blood mononuclear cell (PBMC) extracts. Fluorescence activated cell-sorting (FACS) data revealed cellular yields from 85.90 to 95.18%, of relatively pure DCs isolated from patients' PBMCs. Although HIV-1 RNA gag and DNA RU/5 were detected in all PBMC samples isolated from the patients, proviral DNA and viral RNA forms were not detected in any of the DC isolates. In addition, no replication-competent virus was demonstrated in DC coculture assays, while virus was isolated from each patients' CD8+ T-lymphocyte-depleted PBMC cocultures. Furthermore, HIV-1 gag proviral DNA was not detected in either plasmacytoid or myeloid DC subfractions. The current study suggests that in HIV-1-infected individuals treated with suppressive HAART, peripheral blood DCs do not carry HIV-1 proviral DNA or viral particles attached to their surface. These populations of peripheral blood DCs are likely not a major HIV-1 reservoir in patients on HAART with clinically undetectable plasma viral RNA.