Polyene phosphatidylcholine enhances the therapeutic response of oxaliplatin in gastric cancer through Nrf2/HMOX1 mediated ferroptosis

Oxaliplatin (OXA)-based chemotherapy is one of the first-line treatments for advanced gastric cancer. However, the potential risk for chemotherapy-induced hepatic injury can hinder its effectiveness. Polyene phosphatidylcholine (PPC) is often used as a hepatoprotective agent to counter OXA-induced hepatic injury; however, its impact on the antitumour effectiveness of OXA remains uncertain. Our retrospective study examined 98 patients with stage IV gastric cancer to assess the impact of PPC on progression-free survival (PFS) and disease control rate (DCR). Furthermore, in vitro and in vivo assays were conducted to elucidate the combined biological effects of OXA and PPC (OXA+PPC) on gastric cancer. RNA sequencing, luciferase reporter assays, live/dead cell assays, immunofluorescence, and western blotting were used to identify the activated signalling pathways and downstream factors post OXA+PPC treatment. The findings indicated that PPC served as an independent prognostic factor, correlating with prolonged PFS and improved DCR in patients with gastric cancer. The combination of OXA and PPC significantly inhibited tumour cell growth both in vitro and in vivo. RNA sequencing revealed that OXA+PPC treatment amplified reactive oxygen species and ferroptosis signalling pathways. Mechanistically, OXA+PPC upregulated the expression of haem oxygenase-1 by promoting the nuclear migration of nuclear factor erythroid 2-related factor (Nrf2), thereby enhancing its transcriptional activity. Drug-molecule docking analysis demonstrated that PPC competitively bound to the peptide structural domains of both Nrf2 and Kelch-like ECH-associated protein 1 (KEAP1), accounting for the increased translocation of Nrf2. In conclusion, our study reveals the synergistic antitumour potential of PPC and OXA while protecting patients against hepatic injury. This suggests a promising combined treatment approach for patients with advanced gastric cancer.

Aldo-keto reductase-7A2 protects against atorvastatin-induced hepatotoxicity via Nrf2 activation

Atorvastatin (ATO), as a cholesterol-lowering drug, was the world's best-selling drug in the early 2000s. However, ATO overdose-induced liver or muscle injury is a threat to many patients, which restricts its application. Previous studies suggest that ATO overdose is accompanied with ROS accumulation and increased lipid peroxidation, which are the leading causes of ATO-induced liver damage. This study is, therefore, carried out to investigate the roles of anti-oxidant pathways and enzymes in protection against ATO-induced hepatotoxicity. Here we show that in ATO-challenged HepG2 cells, the expression levels of transcription factor NFE2L2/Nrf2 (nuclear factor erythroid 2 p45-related factor 2) are significantly upregulated. When Nrf2 is pharmacologically inhibited or genetically inactivated, ATO-induced cytotoxicity is significantly aggravated. Aldo-keto reductase-7A (AKR7A) enzymes, transcriptionally regulated by Nrf2, are important for bioactivation and biodetoxification. Here, we reveal that in response to ATO exposure, mRNA levels of human AKR7A2 are significantly upregulated in HepG2 cells. Furthermore, knockdown of AKR7A2 exacerbates ATO-induced hepatotoxicity, suggesting that AKR7A2 is essential for cellular adaptive response to ATO-induced cell damage. In addition, overexpression of AKR7A2 in HepG2 cells can significantly mitigate ATO-induced cytotoxicity and this process is Nrf2-dependent. Taken together, these findings indicate that Nrf2-mediated AKR7A2 is responsive to high concentrations of ATO and contributes to protection against ATO-induced hepatotoxicity, making it a good candidate for mitigating ATO-induced side effects.

[Analysis of clinical characteristics and molecular genetics in eighteen patients with 1q21.1 microdeletion syndrome]

OBJECTIVE

To explore the clinical characteristics of 1q21.1 microdeletion by using single nucleotide polymorphism microarrays (SNP array).

METHODS

Eighteen cases of 1q21.1 microdeletion syndrome diagnosed at the Longgang District Maternal and Child Health Care Hospital of Shenzhen City from June 2017 to December 2022 were selected as the study subjects. Clinical data of the patients were collected. Results of chromosomal karyotyping and SNP assay were retrospectively analyzed.

RESULTS

Among the 18 cases with 1q21.1 microdeletions, 13 had a deletion between BP3 and BP4, 4 had a deletion between BP1/BP2 and BP4, whilst 1 had a proximal 1q21.1 deletion (between BP2 and BP3) involving the Thrombocytopenia-absent radius (TAR) region. The deletions had spanned from 360 kb to 3.9 Mb, which encompassed the GJA5, GJA8, CHD1L, RBM8AB and other morbid genes. In three families, the proband child has inherited the same 1q21.1 microdeletion from their parents, whose clinical phenotype was normal or slightly abnormal. The clinical phenotypes of 1q21.1 microdeletion had included cognitive or behavioral deficits in 9 cases (9/18, 50.0%), growth retardation in 8 cases (8/18, 44.4%), craniofacial deformities in 7 cases (7/18, 38.8%), cardiovascular malformations in 5 cases (5/18, 27.8%), and microcephaly in 3 cases (3/18, 16.7%).

CONCLUSION

1q21.1 microdeletion syndrome has incomplete penetrance and varied expression such as intellectual impairment, growth and development delay, and microcephaly, with a wide range of non-specific phenotypes.

Native T1-mapping as a predictor of progressive renal function decline in chronic kidney disease patients

BACKGROUND

To investigate the potential of Native T1-mapping in predicting the prognosis of patients with chronic kidney disease (CKD).

METHODS

We enrolled 119 CKD patients as the study subjects and included 20 healthy volunteers as the control group, with follow-up extending until October 2022. Out of these patients, 63 underwent kidney biopsy measurements, and these patients were categorized into high (25-50%), low (< 25%), and no renal interstitial fibrosis (IF) (0%) groups. The study's endpoint event was the initiation of renal replacement therapy, kidney transplantation, or an increase of over 30% in serum creatinine levels. Cox regression analysis determined factors influencing unfavorable kidney outcomes. We employed Kaplan-Meier analysis to contrast kidney survival rates between the high and low T1 groups. Additionally, receiver-operating characteristic (ROC) curve analysis assessed the predictive accuracy of Native T1-mapping for kidney endpoint events.

RESULTS

T1 values across varying fibrosis degree groups showed statistical significance (F = 4.772, P < 0.05). Multivariate Cox regression pinpointed 24-h urine protein, cystatin C(CysC), hemoglobin(Hb), and T1 as factors tied to the emergence of kidney endpoint events. Kaplan-Meier survival analysis revealed a markedly higher likelihood of kidney endpoint events in the high T1 group compared to the low T1 value group (P < 0.001). The ROC curves for variables (CysC, T1, Hb) tied to kidney endpoint events demonstrated area under the curves(AUCs) of 0.83 (95%CI: 0.75-0.91) for CysC, 0.77 (95%CI: 0.68-0.86) for T1, and 0.73 (95%CI: 0.63-0.83) for Hb. Combining these variables elevated the AUC to 0.88 (95%CI: 0.81-0.94).

CONCLUSION

Native T1-mapping holds promise in facilitating more precise and earlier detection of CKD patients most at risk for end-stage renal disease.

Efficacy and safety of local ablative therapy for patients with NSCLC and coexisting interstitial lung disease

BACKGROUND

The effective therapeutic approach is still an unmet need for patients diagnosed with both lung cancer and interstitial lung disease (ILD). This is primarily due to the possible risk of ILD exacerbation caused by surgery or radiotherapy. The current study aimed to investigate the efficacy and safety of local ablative therapy (LAT) for this specific population.

METHODS

Consecutive patients with non-small cell lung cancer (NSCLC) and ILD who received LAT between January 2018 and August 2022 were enrolled, and propensity score matching (PSM) was utilized to match the non-ILD group. The primary endpoint was recurrence-free survival (RFS), and secondary endpoints included overall survival (OS), adverse events (AEs) and hospital length of stay (HLOS).

RESULTS

The PSM algorithm yielded matched pairs in the ILD group (n = 25) and non-ILD group (n = 72) at a ratio of 1:3. There were no statistically significant differences in RFS (median 16.4 vs. 18 months; HR = 1.452, p = 0.259) and OS (median: not reached vs. 47.9 months; HR = 1.096, p = 0.884) between the two groups. Meanwhile, no acute exacerbation of ILD was observed in the ILD group. However, the incidence of pneumothorax, especially pneumothorax requiring chest tube drainage, was significantly higher (36.0% vs. 11.2%, p = 0.005) among patients with NSCLC and co-existing ILD, which resulted in longer HLOS (p = 0.045).

CONCLUSION

Although ILD was associated with a higher incidence of pneumothorax, the efficacy of LAT for NSCLC patients with ILD was comparable to those without ILD, suggesting that LAT might be a reliable and effective treatment option for this population, particularly in the early stage.

A deep-learning model for intracranial aneurysm detection on CT angiography images in China: a stepwise, multicentre, early-stage clinical validation study

BACKGROUND

Artificial intelligence (AI) models in real-world implementation are scarce. Our study aimed to develop a CT angiography (CTA)-based AI model for intracranial aneurysm detection, assess how it helps clinicians improve diagnostic performance, and validate its application in real-world clinical implementation.

METHODS

We developed a deep-learning model using 16 546 head and neck CTA examination images from 14 517 patients at eight Chinese hospitals. Using an adapted, stepwise implementation and evaluation, 120 certified clinicians from 15 geographically different hospitals were recruited. Initially, the AI model was externally validated with images of 900 digital subtraction angiography-verified CTA cases (examinations) and compared with the performance of 24 clinicians who each viewed 300 of these cases (stage 1). Next, as a further external validation a multi-reader multi-case study enrolled 48 clinicians to individually review 298 digital subtraction angiography-verified CTA cases (stage 2). The clinicians reviewed each CTA examination twice (ie, with and without the AI model), separated by a 4-week washout period. Then, a randomised open-label comparison study enrolled 48 clinicians to assess the acceptance and performance of this AI model (stage 3). Finally, the model was prospectively deployed and validated in 1562 real-world clinical CTA cases.

FINDINGS

The AI model in the internal dataset achieved a patient-level diagnostic sensitivity of 0·957 (95% CI 0·939-0·971) and a higher patient-level diagnostic sensitivity than clinicians (0·943 [0·921-0·961] vs 0·658 [0·644-0·672]; p<0·0001) in the external dataset. In the multi-reader multi-case study, the AI-assisted strategy improved clinicians' diagnostic performance both on a per-patient basis (the area under the receiver operating characteristic curves [AUCs]; 0·795 [0·761-0·830] without AI vs 0·878 [0·850-0·906] with AI; p<0·0001) and a per-aneurysm basis (the area under the weighted alternative free-response receiver operating characteristic curves; 0·765 [0·732-0·799] vs 0·865 [0·839-0·891]; p<0·0001). Reading time decreased with the aid of the AI model (87·5 s vs 82·7 s, p<0·0001). In the randomised open-label comparison study, clinicians in the AI-assisted group had a high acceptance of the AI model (92·6% adoption rate), and a higher AUC when compared with the control group (0·858 [95% CI 0·850-0·866] vs 0·789 [0·780-0·799]; p<0·0001). In the prospective study, the AI model had a 0·51% (8/1570) error rate due to poor-quality CTA images and recognition failure. The model had a high negative predictive value of 0·998 (0·994-1·000) and significantly improved the diagnostic performance of clinicians; AUC improved from 0·787 (95% CI 0·766-0·808) to 0·909 (0·894-0·923; p<0·0001) and patient-level sensitivity improved from 0·590 (0·511-0·666) to 0·825 (0·759-0·880; p<0·0001).

INTERPRETATION

This AI model demonstrated strong clinical potential for intracranial aneurysm detection with improved clinician diagnostic performance, high acceptance, and practical implementation in real-world clinical cases.

FUNDING

National Natural Science Foundation of China.

TRANSLATION

For the Chinese translation of the abstract see Supplementary Materials section.

Optimal response to tislelizumab plus chemotherapy in metastatic triple-negative breast cancer: a case report and literature review

Metastatic triple-negative breast cancer (mTNBC) has the worst prognosis among breast cancer subtypes. Immune checkpoint inhibitors (ICIs) plus chemotherapy have promising survival benefits. Herein, we report a 51-year-old woman whose metastatic lesions were diagnosed as triple-negative subtype and who received tislelizumab plus eribulin treatment and achieved excellent efficacy. To our knowledge, this study is the first attempt to present tislelizumab in combination with eribulin for mTNBC treatment. New treatments resulting in prolonged survival and durable clinical responses would benefit mTNBC patients. Then, we summarize the possible influencing factors of the interaction between tislelizumab and eribulin.

Score Dynamics: Scaling Molecular Dynamics with Picoseconds Time Steps via Conditional Diffusion Model

We propose score dynamics (SD), a general framework for learning accelerated evolution operators with large timesteps from molecular dynamics (MD) simulations. SD is centered around scores or derivatives of the transition log-probability with respect to the dynamical degrees of freedom. The latter play the same role as force fields in MD but are used in denoising diffusion probability models to generate discrete transitions of the dynamical variables in an SD time step, which can be orders of magnitude larger than a typical MD time step. In this work, we construct graph neural network-based SD models of realistic molecular systems that are evolved with 10 ps timesteps. We demonstrate the efficacy of SD with case studies of the alanine dipeptide and short alkanes in aqueous solution. Both equilibrium predictions derived from the stationary distributions of the conditional probability and kinetic predictions for the transition rates and transition paths are in good agreement with MD. Our current SD implementation is about 2 orders of magnitude faster than the MD counterpart for the systems studied in this work. Open challenges and possible future remedies to improve SD are also discussed.

Role of C/EBP Homologous Protein in Vascular Stenosis After Carotid Artery Injury

The study aims to explore the fluctuating expression of C/EBP Homologous Protein (CHOP) following rat carotid artery injury and its central role in vascular stenosis. Using in vivo rat carotid artery injury models and in vitro ischemia and hypoxia cell models employing human aortic endothelial cells (HAECs) and vascular smooth muscle cells (T/G HA-VSMCs), a comprehensive investigative framework was established. Histological analysis confirmed intimal hyperplasia in rat models. CHOP expression in vascular tissues was assessed using Western blot and immunohistochemical staining, and its presence in HAECs and T/G HA-VSMCs was determined through RT-PCR and Western blot. The study evaluated HAEC apoptosis, inflammatory cytokine secretion, cell proliferation, and T/G HA-VSMCs migration through Western blot, ELISA, CCK8, and Transwell migration assays. The rat carotid artery injury model revealed substantial fibrous plaque formation and vascular stenosis, resulting in an increased intimal area and plaque-to-lumen area ratio. Notably, CHOP is markedly elevated in vessels of the carotid artery injury model compared to normal vessels. Atorvastatin effectively mitigated vascular stenosis and suppresses CHOP protein expression. In HAECs, ischemia and hypoxia-induced CHOP upregulation, along with heightened TNFα, IL-6, caspase3, and caspase8 levels, while reducing cell proliferation. Atorvastatin demonstrated a dose-dependent suppression of CHOP expression in HAECs. Downregulation of CHOP or atorvastatin treatment led to reduced IL-6 and TNFα secretion, coupled with augmented cell proliferation. Similarly, ischemia and hypoxia conditions increased CHOP expression in T/G HA-VSMCs, which was concentration-dependently inhibited by atorvastatin. Furthermore, significantly increased MMP-9 and MMP-2 concentrations in the cell culture supernatant correlated with enhanced T/G HA-VSMCs migration. However, interventions targeting CHOP downregulation and atorvastatin usage curtailed MMP-9 and MMP-2 secretion and suppressed cell migration. In conclusion, CHOP plays a crucial role in endothelial injury, proliferation, and VSMCs migration during carotid artery injury, serving as a pivotal regulator in post-injury fibrous plaque formation and vascular remodeling. Statins emerge as protectors of endothelial cells, restraining VSMCs migration by modulating CHOP expression.

The effect of gonadotropin-releasing hormone analog treatment on the endocrine system in central precocious puberty patients: a meta-analysis

OBJECTIVES

Gonadotropin-releasing hormone (GnRHa) is the first choice for the treatment of patients with central precocious puberty (CPP). However, the effects of GnRHa on the endocrine system of CPP patients, including insulin sensitivity, lipid level, thyroid function, bone mineral density (BMD), and testosterone (T) level, are currently contradictory. Therefore, the long-term safety of GnRHa therapy remains controversial.

CONTENT

A systematic literature search was performed using PubMed, Embase, Cochrane Library, and CNKI databases. The changes in HOMA-IR, TG, LDL-C, HDL-C, TSH, FT3, FT4, T, and BMD in CPP patients before and after GnRHa treatment were compared by meta-analysis. As the heterogeneity between studies, we estimated standard deviation mean differences (SMDs) and 95 % confidence intervals (CIs) using a random-effects model. Egger's test was used to assess publication bias.

SUMMARY

A total of 22 studies were included in our meta-analysis. Compared with before GnRHa treatment, there were no statistically significant differences in endocrine indicators including HOMA-IR, TG, LDL-C, HDL-C, TSH, FT4, FT3, T, and BMD of CPP patients treated with GnRHa.

OUTLOOK

Treatment with GnRHa for central precocious puberty will not increase the adverse effect on the endocrine system.

Dynamic contrast-enhanced magnetic resonance imaging in cervical cancer: correlation between quantitative parameters and molecular markers hypoxia-inducible factors-1-alpha, vascular endothelial growth factor, and Ki-67

AIM

To investigate whether dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has the potential to non-invasively detect microenvironmental condition by quantitatively measuring blood perfusion, vessel wall permeability, and vascularity, and to elucidate the possible correlations between DCE-MRI quantitative parameters and the expression level of hypoxia, vascularity, and cell proliferation related molecular biomarkers.

MATERIALS AND METHODS

In this prospective single center clinical study, 58 patients diagnosed with cervical cancer underwent DCE-MRI before anticancer treatment were enrolled. Ktrans, Kep, Ve, and Vp were generated from Extended Toft's model. Then patients conducted colposcopy biopsy within 1 week after DCE-MRI. Pretreatment expression levels of HIF-1α, VEGF and Ki-67 were assessed and scored by immunohistochemistry on colposcopy obtained tumor specimens.

RESULTS

In HIF-1α low-expression group, Ktrans (p=0.031) and Kep (p=0.012) values were significantly higher than the high-expression group. In VEGF high-expression group, Ktrans (p=0.044) and Ve values (p=0.021) were significantly higher than the low-expression group. In Ki-67 high-expression group, Ktrans (p=0.026) and Kep (p=0.033) were significantly higher than the low-expression group. Multiple linear regression analyses and Pearson correlation revealed that Ktrans independently negatively correlated with HIF-1α expression, Ve independently positively correlated with VEGF, and Kep independently positively correlated with Ki-67. The area under the ROC curves of Ktrans for HIF-1α, Ve for VEGF, and Kep for Ki-67 were 0.728, 0.743, 0.730, respectively.

CONCLUSION

Our results suggest that DCE-MRI quantitative parameters could be potentially used as imaging markers for non-invasively detecting microenvironmental hypoxia, vascularity and proliferation in cervical cancer patients.

Prenatal diagnosis, pregnancy determination and follow up of sex chromosome aneuploidy screened by non-invasive prenatal testing from 122 453 unselected singleton pregnancies: A retrospective analysis of 7-year experience

The phenotype of SCA patients are diversities, make prenatal counseling and parental decision-making following the prenatal diagnosis of SCA more complicated and challenging. NIPT has higher sensitivity and specificity in screening trisomy 21 syndrome, but the effectiveness of NIPT in detecting SCA is still controversial. This study is a large-scale retrospective cohort of positive SCA screened from unselected singleton pregnancies by non-invasive prenatal testing (NIPT) from a single prenatal center of a tertiary hospital. Clinical information, indications, diagnostic results, ultrasound findings, pregnancy determinations, and follow-up were reviewed and analyzed. 596 cases of SCA positive were screened out of 122 453, giving a positive detection rate of 0.49%. 510 cases (85.6%) conducted with amniocentesis to detect fetal chromosome, of which 236 were confirmed as true positive of SCA with PPV of 46.3% (236/510). Of the 236 cases confirmed as true positive SCA, 114 cases (48.3%)chose to terminate the pregnancy (93.0%, 65.3%, 15.4% and 10.9% for 45,X, 47,XXY, 47,XXX and 47,XYY, respectively), 122 cases (51.7%) elected to continue the pregnancy. In conclusions, NIPT as a first-tier routine method for screening autosomal aneuploidies, also could play an important role in screening SCA. Low-risk pregnant women are the main indication for the detection of SCA as NIPT test provides to non-selective population. For 47,XXX and 47,XYY with mild phenotype, couples would like to continue the pregnancy. But for 45,X and 47,XXY, parents apt to terminate pregnancy no matter ultrasound abnormalities were found or not.

Efficacy and safety of rifampicin-based triple therapy for non-puerperal mastitis: A single-arm, open-label, prospective clinical trial

OBJECTIVES

To assess the efficacy and safety of rifampicin-based triple therapy (rifampicin, isoniazid, and ethambutol) for treating NPM.

METHODS

This single-center, single-arm, prospective clinical trial was conducted at the Second Hospital of Shandong University (Jinan, China). Patients with pathologically diagnosed granulomatous lobular mastitis and periductal mastitis received triple drugs, i.e., rifampicin (450 mg/day), isoniazid (300 mg/day), and ethambutol (15 mg/kg/day), until complete response or the investigator decided to discontinue treatment. The primary endpoint was the complete response rate (CRR) assessed by the investigator. The secondary endpoints included the overall remission rate (ORR), recurrence rate (RR), and safety.

RESULTS

A total of 218 patients were enrolled in the study between January 1, 2013 and October 31, 2020. With a median follow-up time of 48 months, the CRR and the ORR were 78.44% and 94.04%, respectively. While 13 patients (5.96%) demonstrated no response and 19 relapsed (8.72%). Adverse events (AEs) were not common. The most common AEs during treatment were liver dysfunction (1.83%), gastrointestinal reactions (1.83%), fatigue (1.83%), erythema (1.38%), and menstrual disorders (0.92%).

CONCLUSION

Rifampicin, isoniazid, and ethambutol demonstrated promising response rates with acceptable safety profiles in patients with NPM. Further confirmatory trial is warranted in the future.

TRIAL REGISTRATION

The study was approved by the Ethics Committee of the Second Hospital of Shandong University and retrospectively registered at the China Clinical Trial Registration Center (registration number: ChiCTR2100049591).

Effects of collagen-based coating with chitosan and ε-polylysine on sensory, texture, and biochemical changes of refrigerated Nemipterus virgatus fillets

In order to evaluate the effects of chitosan, ε-polylysine, and collagen on the preservation properties of refrigerated Nemipterus virgatus, samples were tested with different treatments for 10 days, namely chitosan, ε-polylysine and collagen (CH + ε-PL + CA), chitosan and ε-polylysine (CH + ε-PL), chitosan and collagen (CH + CA), ε-polylysine and collagen (ε-PL + CA), and the uncoated sample (CK). The results demonstrated that the bio-coating exhibited better preservation effects. The CH + ε-PL + CA, CH + ε-PL, CH + CA, ε-PL + CA treatments could significantly inhibit bacterial growth and retard the increase of total volatile base nitrogen (TVB-N), 2-thiobarbituric acid (TBA), K-value, and total viable counts (TVC) in N. virgatus fillets. The pH of all samples decreased and reached its lowest value on day 6, then increased significantly at the end of the experiment (p < .05). Water-holding capacity (WHC) of all the groups decreased continuously throughout storage, and CK reached 66.03% on day 6, which is significantly lower than CH + ε-PL + CA, CH + ε-PL, CH + CA, and ε-PL + CA (p < .05). On the contrary, the sensory scores of CH + ε-PL + CA, CH + ε-PL, CH + CA, and ε-PL + CA were significantly higher than the control, and the score of CH + ε-PL + CA (p < .05) was the best among all the groups. In terms of texture, CH + PL + CA also showed less cell shrinkage and tighter muscle fiber arrangement compared to other treatments. To sum up, the CH + PL + CA bio-coating proved to be a promising method for maintaining the storage quality of N. virgatus under refrigerated storage conditions.

Cryo-EM structures of the plant plastid-encoded RNA polymerase

Chloroplasts are green plastids in the cytoplasm of eukaryotic algae and plants responsible for photosynthesis. The plastid-encoded RNA polymerase (PEP) plays an essential role during chloroplast biogenesis from proplastids and functions as the predominant RNA polymerase in mature chloroplasts. The PEP-centered transcription apparatus comprises a bacterial-origin PEP core and more than a dozen eukaryotic-origin PEP-associated proteins (PAPs) encoded in the nucleus. Here, we determined the cryo-EM structures of Nicotiana tabacum (tobacco) PEP-PAP apoenzyme and PEP-PAP transcription elongation complexes at near-atomic resolutions. Our data show the PEP core adopts a typical fold as bacterial RNAP. Fifteen PAPs bind at the periphery of the PEP core, facilitate assembling the PEP-PAP supercomplex, protect the complex from oxidation damage, and likely couple gene transcription with RNA processing. Our results report the high-resolution architecture of the chloroplast transcription apparatus and provide the structural basis for the mechanistic and functional study of transcription regulation in chloroplasts.

Magnesium Transporter MgtA revealed as a Dimeric P-type ATPase

Magnesium (Mg2+) uptake systems are present in all domains of life given the vital role of this ion. Bacteria acquire Mg2+ via conserved Mg2+ channels and transporters. The transporters are required for growth when Mg2+ is limiting or during bacterial pathogenesis, but, despite their significance, there are no known structures for these transporters. Here we report the first structure of the Mg2+ transporter MgtA solved by single particle cryo-electron microscopy (cryo-EM). Using mild membrane extraction, we obtained high resolution structures of both a homodimeric form (2.9 Å), the first for a P-type ATPase, and a monomeric form (3.6 Å). Each monomer unit of MgtA displays a structural architecture that is similar to other P-type ATPases with a transmembrane domain and two soluble domains. The dimer interface consists of contacts between residues in adjacent soluble nucleotide binding and phosphotransfer regions of the haloacid dehalogenase (HAD) domain. We suggest oligomerization is a conserved structural feature of the diverse family of P-type ATPase transporters. The ATP binding site and conformational dynamics upon nucleotide binding to MgtA were characterized using a combination of cryo-EM, molecular dynamics simulations, hydrogen-deuterium exchange mass spectrometry, and mutagenesis. Our structure also revealed a Mg2+ ion in the transmembrane segments, which, when combined with sequence conservation and mutagenesis studies, allowed us to propose a model for Mg2+ transport across the lipid bilayer. Finally, our work revealed the N-terminal domain structure and cytoplasmic Mg2+ binding sites, which have implications for related P-type ATPases defective in human disease.

An advanced machine learning method for simultaneous breast cancer risk prediction and risk ranking in Chinese population: A prospective cohort and modeling study

BACKGROUND

Breast cancer (BC) risk-stratification tools for Asian women that are highly accurate and can provide improved interpretation ability are lacking. We aimed to develop risk-stratification models to predict long- and short-term BC risk among Chinese women and to simultaneously rank potential non-experimental risk factors.

METHODS

The Breast Cancer Cohort Study in Chinese Women, a large ongoing prospective dynamic cohort study, includes 122,058 women aged 25-70 years from the eastern part of China. We developed multiple machine-learning risk prediction models using parametric models (penalized logistic regression, bootstrap, and ensemble learning), which were the short-term ensemble penalized logistic regression (EPLR) risk prediction model and the ensemble penalized long-term (EPLT) risk prediction model to estimate BC risk. The models were assessed based on calibration and discrimination, and following this assessment, they were externally validated in new study participants from 2017 to 2020.

RESULTS

The AUC values of the short-term EPLR risk prediction model were 0.800 for the internal validation and 0.751 for the external validation set. For the long-term EPLT risk prediction model, the area under the receiver operating characteristic curve was 0.692 and 0.760 in internal and external validations, respectively. The net reclassification improvement index of the EPLT relative to the Gail and the Han Chinese Breast Cancer Prediction Model (HCBCP) models for external validation was 0.193 and 0.233, respectively, indicating that the EPLT model has higher classification accuracy.

CONCLUSIONS

We developed the EPLR and EPLT models to screen populations with a high risk of developing BC. These can serve as useful tools to aid in risk-stratified screening and BC prevention.

Ultrasonic microbubbles promote mesenchymal stem cell homing to the fibrotic liver via upregulation of CXCR4 expression

OBJECTIVE

To investigate the mechanism of ultrasound microbubbles (UTMB) promoting stem cells homing to fibrotic liver.

METHODS

Bone marrow derived mesenchymal stem cells (BMSCs) were divided into 5 groups with or without ultrasound microbubbles and continuously irradiated with ultrasound conditions of frequency 1 MHZ and output power 0.6 W/cm2 for different times, and then injected into a mouse model of liver fibrosis through the tail vein with or without ultrasound microbubbles, with sound intensity. The effect of ultrasound microbubbles on MSC expression of CXC chemokine receptor 4 (CXCR4) and homing fibrotic liver was evaluated by flow cytometry (FCM), western blot (WB) and immunohistochemistry (IHC) analysis.

RESULTS

The level of CXCR4 expression was significantly higher in the ultrasound microbubble group than in the non-intervention group (P < 0.05), and the number of MSC and the rate of CXCR4 receptor positivity in the ultrasound microbubble-treated liver tissues were significantly higher than in the non-intervention group (P < 0.01).

CONCLUSION

Ultrasonic microbubbles can promote the expression of CXCR4 on the surface of MSCs, thus improving the homing rate of MSCs in fibrotic liver.

Mechanisms and targeted reversion/prevention of hepatic fibrosis caused by the non-hereditary toxicity of benzo(a)pyrene

The effect of long term exposure to low concentrations of environmental pollutants on hepatic disorders is a major public health concern worldwide. Polycyclic aromatic hydrocarbons (PAHs) are a class of persistent organic pollutants. In recent years, an increasing number of studies have focused on the deleterious effects of low concentrations of PAHs in the initiation or exacerbation of the progression of chronic liver disease. However, the underlying molecular mechanisms and effective intervention methods remain unclear. Here, we found that in hepatocytes, a low concentration of benzo(a)pyrene (B[a]P, an indicator of PAHs) chronic exposure continuously activated 14-3-3η via an epigenetic accumulation of DNA demethylation. As a "switch like" factor, 14-3-3η activated its downstream PI3K/Akt signal, which in turn promoted vascular endothelial growth factor (VEGF) production and secretion. As the characteristic fibrogenic paracrine factor regulated by B[a]P/14-3-3η, VEGF significantly induced the neovascularization and activation of hepatic stellate cells, leading to the development of hepatic fibrosis. Importantly, targeted 14-3-3η by using its specific inhibitor invented by our lab could prevent B[a]P-induced hepatic fibrosis, and could even reverse existent hepatic fibrosis caused by B[a]P. The present study not only revealed novel mechanisms, but also proposed an innovative approach for the targeted reversion/prevention of the harmful effects of exposure to PAHs on chronic liver disease.

[Study of the effects of dietary patterns on glycemic control in community type 2 diabetic mellitus patients]

Objective: To understand the impact of diet on glycemic control in community-managed patients with type 2 diabetes mellitus (T2DM) and provide evidence for implementing prevention strategies and measures for diabetes patients. Methods: Eight communities were randomly selected from Changshu and Wuhan in 2015, and T2DM patients managed in the community were selected to conduct questionnaire surveys, physical measurements, and blood glucose testing. Factor analysis was used to obtain dietary patterns. A binary logistic regression model was used to analyze the factors affecting glycemic control. Results: Finally, 1 818 T2DM patients were included, and the control rate of FPG was 57.59% (95%CI: 55.30%-59.86%), and the control rate of 2 h postprandial blood glucose (2 h PBG) was 24.90% (95%CI: 22.93%- 26.91%). Five dietary patterns were obtained by factor analysis: animal food pattern, fruit-aquatic products-potato patterns, vegetable-grain pattern, egg-milk-bean pattern, and oil-salt patterns. No-conditional multivariate logistic regression analysis showed that after adjusting for confounding factors, the reduced probability of FPG control was related to animal food pattern (OR=0.71, 95%CI: 0.52-0.98) and fruit-aquatic products-potato patterns (OR=0.71, 95%CI: 0.51-0.97). The decrease in the 2 h PBG control probability was related to fruit-aquatic products-potato patterns (OR=0.60, 95%CI: 0.40-0.90). The increased probability of FPG and 2 h postprandial glucose control were both related to vegetable-grain pattern (OR=1.41, 95%CI: 1.03-1.94; OR=1.68, 95%CI: 1.13-2.51) and egg-milk-bean pattern (OR=1.75, 95%CI: 1.25-2.46; OR=1.56, 95%CI: 1.00-2.42). Compared with the Q4 group of egg-milk-bean pattern, the FPG control rate of the combination of "fruit-aquatic products-potato pattern (Q4 group), vegetable-grain pattern (Q2 group), egg-milk-bean pattern (Q3 group)" was higher (OR=6.79, 95%CI: 1.15-40.23, P=0.035). Compared with the Q4 group of vegetable-grain pattern, the combination of "fruit-aquatic products-potato pattern (Q4 group), vegetable-grain pattern (Q3 group), egg-milk-bean pattern (Q2 group), oil-salt pattern (Q2 group)" had higher control rate of 2 h PBG (OR=12.78, 95%CI: 1.26-130.05, P=0.031). Conclusions: A proper combination of dietary patterns and dietary patterns are more conducive to the control of FPG and 2 h PBG in T2DM patients managed in the communities of Wuhan and Changshu. Patient nutrition education should be strengthened, and the food-matching ability of patients should be improved.

Bone marrow mesenchymal stem cell-derived exosomes promote osteoblast proliferation, migration and inhibit apoptosis by regulating KLF3-AS1/miR-338-3p

AIM

This study aimed to investigate the effect and mechanism of bone marrow mesenchymal stem cell-derived exosomes on osteoblast function.

METHODS

The expression of KLF3-AS1 and miR-338-3p in serum of fracture patients was detected by qRT-PCR. Exosomes from BMSCs were isolated by ultrafast centrifugation. MC3T3-E1 cells were cultured in vitro as experimental cells. Intracellular gene expression was regulated by transfection of si-KLF3-AS1 or miR-338-3p inhibitors. MTT assay, Transwell assay and flow cytometry were used to evaluate cell viability, migration, and apoptosis. The luciferase reporter gene was used to verify the targeting relationship between KLF3-AS1 and miR-338-3p. Bioinformatics analysis was used to identify the basic functions and possible enrichment pathways of miR-338-3p target genes.

RESULTS

The expressions of KLF3-AS1 and miR-338-3p in the serum of fracture patients were down-regulated and up-regulated, respectively. The expression of KLF3-AS1 was increased in MC3T3-E1 cells cultured with BMSCs-Exo, while the viability and migration ability of MC3T3-E1 cells were enhanced, and the apoptosis ability was weakened. Further analysis revealed miR-338-3p was the target gene of KLF3-AS1. The expression of miR-338-3p was downregulated in MC3T3-E1 cells cultured with BMSCs-Exo. Inhibition of miR-338-3p in MC3T3-E1 cells enhanced the viability and migration ability of MC3T3-E1 cells when cultured with BMSCs-Exo, while suppressing apoptosis. Bioinformatics analysis demonstrated that the target genes of miR-338-3p were predominantly localized at the axon's initiation site, involved in biological processes such as development and growth regulation, and mainly enriched in MAPK and ErbB signaling pathways.

CONCLUSION

In vitro, BMSCs-Exo exhibits the capacity to enhance proliferation and migration while inhibiting apoptosis of MC3T3-E1 cells, potentially achieved through modulation of KLF3-AS1 and miR-338-3p expression in MC3T3-E1 cells.

Polymer-extracted structure of the mechanosensitive channel MscS reveals the role of protein-lipid interactions in the gating cycle

Membrane protein structure determination is not only technically challenging but is further complicated by the removal or displacement of lipids, which can result in non-native conformations or a strong preference for certain states at the exclusion of others. This is especially applicable to mechanosensitive channels (MSC's) that evolved to gate in response to subtle changes in membrane tension transmitted through the lipid bilayer. E. coli MscS, a model bacterial system, is an ancestral member of the large family of MSCs found across all phyla of walled organisms. As a tension sensor, MscS is very sensitive and highly adaptive; it readily opens under super-threshold tension and closes under no tension, but under lower tensions, it slowly inactivates and can only recover when tension is released. However, existing cryo-EM structures do not explain the entire functional gating cycle of open, closed, and inactivated states. A central question in the field has been the assignment of the frequently observed non-conductive conformation to either a closed or inactivated state. Here, we present a 3 Å MscS structure in native nanodiscs obtained with Glyco-DIBMA polymer extraction, eliminating the lipid removal step that is common to all previous structures. Besides the protein in the non-conductive conformation, we observe well-resolved densities of four endogenous phospholipid molecules intercalating between the lipid-facing and pore-lining helices in preferred orientations. Mutations of positively charged residues coordinating these lipids inhibit MscS inactivation, whereas removal of a negative charge near the lipid-filled crevice increases inactivation. The functional data allows us to assign this class of structures to the inactivated state. This structure reveals preserved lipids in their native locations, and the functional effects of their destabilization illustrate a novel inactivation mechanism based on an uncoupling of the peripheral tension-sensing helices from the gate.

The relationship between inflammatory cytokines and in-hospital complications of acute pancreatitis

OBJECTIVE

Acute necrotic collection (ANC), acute peripancreatic fluid collection (APFC), pleural effusion, and ascites are common early complications of acute pancreatitis. This study aimed to investigate the relationship between 12 serum cytokines and the early complications and severity of acute pancreatitis (AP).

METHODS

We retrospectively analyzed the clinical data of 307 patients with AP, and divided them into severe group and mild-to-moderate group according to the revised Atlanta classification. Propensity score matching was used to control for confounding factors. Binary logistic regression analysis was used to explore the relationship between cytokine levels and early complications of AP.

RESULTS

Serum levels of interleukin (IL)-1β, IL-5, IL-6, IL-8, IL-10, IL-17, and tumor necrosis factor-α were significantly higher in the severe acute pancreatitis (SAP) group than in the non-SAP group (p < .05). After adjusting for confounding factors, the upper quartiles of IL-6, IL-8, and IL-10 were associated with an increased risk of ANC compared with those in the lowest quartile (IL-6: quartile 3, odds ratio [OR] = 3.99, 95% confidence interval [CI] = 1.95-8.16; IL-8: quartile 4, OR = 2.47, 95% CI = 1.27-4.84; IL-10: quartile 2, OR = 2.22, 95% CI = 1.09-4.56). APFC was associated with high serum levels of IL-6 (quartile 3, OR = 1.32, 95% CI = 1.02-1.72), pleural effusions were associated with high serum levels of IL-1β, IL-6, IL-8, and IL-10 (IL-1β: quartile 4, OR = 2.36, 95% CI = 1.21-4.58; IL-6: quartile 3, OR = 4.67, 95% CI = 2.27-9.61; IL-8: quartile 3, OR = 2.95, 95% CI = 1.51-5.79; IL-10: quartile 4, OR = 3.20, 95% CI = 1.61-6.36), and high serum levels of IL-6 and IL-10 were associated with an increased risk of ascites (IL-6: quartile 3, OR = 3.01, 95% CI = 1.42-6.37; IL-10: quartile 3, OR = 2.57, 95% CI = 1.23-5.37).

CONCLUSION

Serum cytokine levels, including IL-1β, IL-6, IL-8, and IL-10 may be associated with the occurrence of early complications of AP. In daily clinical practice, IL-6 may be the most worthwhile cytokine to be detected.

The Value of Percutaneous Contrast-Enhanced Ultrasound in Sentinel Lymph Node Identification, Metastatic Status and Burden Diagnosis in Early Breast Cancer

OBJECTIVE

The aim of this study was to evaluate the value of percutaneous contrast-enhanced ultrasound (PCEUS) in the identification and characterization of sentinel lymph node (SLN).

METHODS

A total of 102 breast cancer patients were collected and underwent preoperative PCEUS, which was used to identify SLN and lymphatic drainage. SLNs were classified into 4 enhancement patterns, including 6 subtypes: homogeneous (I), featured inhomogeneous (II) including inhomogeneous hypoenhancement (IIa) and annular or semi-annular enhancement (IIb), focal filling defect (III) including filling defect area < 50% (IIIa) and filling defect area ≥ 50% (IIIb), and no enhancement (IV). The enhancement patterns of SLNs were compared with the final pathological diagnosis.

RESULTS

The identification rate of SLNs using PCEUS was 100% (102/102); the rate of identification of LCs was 100% (102/102), and the coincidence rate was 98.0% (100/102). Four lymphatic drainage patterns (LDPs) including 5 subtypes were found: single LC/single SLN(74.5%), multiple LCs/ single SLN (13.7%) including 2 subtypes:2 LCs/1 SLN and 3 LCs/1 SLN, single LC/multiple SLNs (7.8%), and multiple LCs/multiple SLNs (3.9%). A total of 86.3% (44/51) of patients without axillary metastasis could be safely selected for types I, IIa, and IIb, while the axillary metastasis rates of types III and IV were 74.4% and 87.5%, respectively (P < .001). Compared with grayscale US, the PCEUS significant improvement in diagnosing metastatic SLNs (.794 versus .579, P < .001). For the SLN metastatic burden, Types I, IIa, IIb, and IIIa had ≤2 SLNs metastases, with a pathological coincidence rate of (64/67, 95.5%), and types IIIb and IV had >2 SLNs metastases, with a pathological coincidence rate of (25/35, 71.4%) (P < .001). The AUC of PCEUS for the diagnosis of SLN metastatic status and burden was .794 and .879, respectively (P < .001).

CONCLUSION

PCEUS has a high identification rate for SLN and has good potential for diagnosing SLN metastatic status and burden by enhancement patterns.

Can pluripotent/multipotent stem cells reverse Parkinson's disease progression?

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by continuous and selective degeneration or death of dopamine neurons in the midbrain, leading to dysfunction of the nigrostriatal neural circuits. Current clinical treatments for PD include drug treatment and surgery, which provide short-term relief of symptoms but are associated with many side effects and cannot reverse the progression of PD. Pluripotent/multipotent stem cells possess a self-renewal capacity and the potential to differentiate into dopaminergic neurons. Transplantation of pluripotent/multipotent stem cells or dopaminergic neurons derived from these cells is a promising strategy for the complete repair of damaged neural circuits in PD. This article reviews and summarizes the current preclinical/clinical treatments for PD, their efficacies, and the advantages/disadvantages of various stem cells, including pluripotent and multipotent stem cells, to provide a detailed overview of how these cells can be applied in the treatment of PD, as well as the challenges and bottlenecks that need to be overcome in future translational studies.

The influence of tactical formation on physical and technical performance across playing positions in the Chinese super league

This study aimed to investigate the impact of tactical formations on the physical and technical performance of professional football players in the Chinese Super League (CSL). A sample of 800 games from the 2015-2021 CSL was analyzed, and players' physical (total distance covered, distance covered while ball in play, number of sprints, sprint distance, and high/middle/low-speed running) and technical (gain/loss of possession, ball retention percentage, challenges, challenge success percentage, passes, and pass success percentage) performance was assessed across six team formations: 3-5-2 (n = 137), 4-3-3 (n = 77), 4-2-3-1 (n = 391), 4-4-2 (n = 257), 3-4-3 (n = 41), and 4-1-4-1 (n = 107). Linear mixed models were used to assess variations in performance indicators across positions and formations. The results demonstrated that central defenders traveled significantly more total and low-speed running distances in the 3-5-2 formation than in the 4-2-3-1 formation (ES range: 0.33-0.34, p < 0.01). Fullbacks in the 3-5-2 formation demonstrated more high-speed running than did those in the 4-4-2 formation (ES = 0.27, p = 0.04). The central midfielders exhibited significantly more sprints and longer sprint distances in the 4-2-3-1 formation than in the 4-4-2 formation (ES range: 0.2-0.24, p < 0.01). Regarding technical performance, central defenders displayed significantly greater ball retention percentages, passes, and pass success rates in the 3-4-3 than in the 3-5-2 formations (ES range: 0.58-0.65, p < 0.01). Moreover, fullbacks and central midfielders executed markedly more passes with superior pass success rates in 4-back formations than in 3-5-2 formations (ES range: 0.2-0.53, p < 0.01). These findings can help coaches and academic staff understand the physical and technical requirements of various positions in various tactical formations, thus optimizing the training process.

Targeting focal adhesion kinase boosts immune response in KRAS/LKB1 co-mutated lung adenocarcinoma via remodeling the tumor microenvironment

BACKGROUND

KRAS mutation is one of the most common oncogenic drivers in NSCLC, however, the response to immunotherapy is heterogeneous owing to the distinct co-occurring genomic alterations. KRAS/LKB1 co-mutated lung adenocarcinoma displays poor response to PD-1 blockade whereas the mechanism remains undetermined.

METHODS

We explored the specific characteristics of tumor microenvironment (TME) in KL tumors using syngeneic KRASG12DLKB1-/- (KL) and KRASG12DTP53-/- (KP) lung cancer mouse models. The impact of focal adhesion kinase (FAK) inhibitor on KL lung tumors was investigated in vitro and in vivo through evaluation of both KL cell lines and KL lung cancer mouse models.

RESULTS

We identified KL tumors as "immune-cold" tumors with excessive extracellular matrix (ECM) collagen deposition that formed a physical barrier to block the infiltration of CD8+T cells. Mechanistically, abundant activated cancer-associated fibroblasts (CAFs) resulted from FAK activation contributed to the formation of the unique TME of KL tumors. FAK inhibition with a small molecular inhibitor could remodel the TME by inhibiting CAFs activation, decreasing collagen deposition and further facilitating the infiltration of anti-tumor immune cells, including CD8+ T cells, DC cells and M1-like macrophages into tumors, hence, converting "immune-cold" KL tumors into "immune-hot" tumors. The combined FAK inhibitor and PD-1 blockade therapy synergistically retarded primary and metastatic tumor growth of KL tumors.

CONCLUSIONS

Our study identified FAK as a promising intervention target for KL tumors and provided basis for the combination of FAK inhibitor with PD-1 blockade in the management of KL lung cancers.

The influence of H2O or/and O2 introduction during the low-temperature gas-phase sulfation of organic COS + CS2 on the conversion and deposition of sulfur-containing species in the sulfated CeO2-OS catalyst for NH3-SCR

Herein, the typical components of blast furnace gas, including H2O and O2, were introduced to improve the NH3-SCR activity of the sulfated CeO2-OS catalyst during the gas-phase sulfation of organic COS + CS2 at 50 °C. The characterization results demonstrate that the introduction of O2 or H2O during gas-phase sulfation enhances the conversion of organic COS + CS2 on a cubic fluorite CeO2 surface and reduces the formation of sulfur and sulfates in the catalyst, but decreases the BET surface area and pore volume of the sulfated CeO2-OS catalyst. However, the introduction of O2 or H2O during the gas-phase sulfation increases the molar ratios of Ce3+/(Ce3+ + Ce4+) and Oβ/(Oα + Oβ + Oγ) on the sulfated CeO2-OS catalyst surface, thus promoting the formation of surface oxygen vacancies and chemisorbed oxygen, and these properties of the catalyst are further enhanced by the co-existence of O2 and H2O. Furthermore, the reduction of sulfates formed under the action of O2 or H2O decreases the weak acid sites of the sulfated CeO2-OS catalyst, but the few and highly dispersive sulfates present stronger reducibility, and the proportion of medium-strong acid sites of the catalyst increases. These factors help to improve the NH3-SCR activity of the sulfated CeO2-OS catalyst. Thus, there exists a synergistic effect of H2O and O2 introduction during gas-phase sulfation on the physical-chemical properties and catalytic performance of the sulfated CeO2-OS catalyst by organic COS + CS2 at 50 °C.

Genomic and transcriptomic analysis of breast cancer identifies novel signatures associated with response to neoadjuvant chemotherapy

BACKGROUND

Neoadjuvant chemotherapy (NAC) has become a standard treatment strategy for breast cancer (BC). However, owing to the high heterogeneity of these tumors, it is unclear which patient population most likely benefit from NAC. Multi-omics offer an improved approach to uncovering genomic and transcriptomic changes before and after NAC in BC and to identifying molecular features associated with NAC sensitivity.

METHODS

We performed whole-exome and RNA sequencing on 233 samples (including matched pre- and post-treatment tumors) from 50 BC patients with rigorously defined responses to NAC and analyzed changes in the multi-omics landscape. Molecular features associated with NAC response were identified and validated in a larger internal, and two external validation cohorts, as well as in vitro experiments.

RESULTS

The most frequently altered genes were TP53, TTN, and MUC16 in both pre- and post-treatment tumors. In comparison with pre-treatment tumors, there was a significant decrease in C > A transversion mutations in post-treatment tumors (P = 0.020). NAC significantly decreased the mutation rate (P = 0.006) of the DNA repair pathway and gene expression levels (FDR = 0.007) in this pathway. NAC also significantly changed the expression level of immune checkpoint genes and the abundance of tumor-infiltrating immune and stroma cells, including B cells, activated dendritic cells, γδT cells, M2 macrophages and endothelial cells. Furthermore, there was a higher rate of C > T substitutions in NAC nonresponsive tumors than responsive ones, especially when the substitution site was flanked by C and G. Importantly, there was a unique amplified region at 8p11.23 (containing ADGRA2 and ADRB3) and a deleted region at 3p13 (harboring FOXP1) in NAC nonresponsive and responsive tumors, respectively. Particularly, the CDKAL1 missense variant P409L (p.Pro409Leu, c.1226C > T) decreased BC cell sensitivity to docetaxel, and ADGRA2 or ADRB3 gene amplifications were associated with worse NAC response and poor prognosis in BC patients.

CONCLUSIONS

Our study has revealed genomic and transcriptomic landscape changes following NAC in BC, and identified novel biomarkers (CDKAL1P409L, ADGRA2 and ADRB3) underlying chemotherapy resistance and poor prognosis, which could guide the development of personalized treatments for BC.

Si-Wu-Tang attenuates liver fibrosis via regulating lncRNA H19-dependent pathways involving cytoskeleton remodeling and ECM deposition

Liver fibrosis is a dynamic wound-healing response characterized by the agglutination of the extracellular matrix (ECM). Si-Wu-Tang (SWT), a traditional Chinese medicine (TCM) formula, is known for treating gynecological diseases and liver fibrosis. Our previous studies demonstrated that long non-coding RNA H19 (H19) was markedly upregulated in fibrotic livers while its deficiency markedly reversed fibrogenesis. However, the mechanisms by which SWT influences H19 remain unclear. Thus, we established a bile duct ligation (BDL)-induced liver fibrosis model to evaluate the hepatoprotective effects of SWT on various cells in the liver. Our results showed that SWT markedly improved ECM deposition and bile duct reactions in the liver. Notably, SWT relieved liver fibrosis by regulating the transcription of genes involved in the cytoskeleton remodeling, primarily in hepatic stellate cells (HSCs), and influencing cytoskeleton-related angiogenesis and hepatocellular injury. This modulation collectively led to reduced ECM deposition. Through extensive bioinformatics analyses, we determined that H19 acted as a miRNA sponge and mainly inhibited miR-200, miR-211, and let7b, thereby regulating the above cellular regulatory pathways. Meanwhile, SWT reversed H19-related miRNAs and signaling pathways, diminishing ECM deposition and liver fibrosis. However, these protective effects of SWT were diminished with the overexpression of H19 in vivo. In conclusion, our study elucidates the underlying mechanisms of SWT from the perspective of H19-related signal networks and proposes a potential SWT-based therapeutic strategy for the treatment of liver fibrosis.

The mortality and years of life lost for community-acquired pneumonia before and during COVID-19 pandemic in China

Background

Community-acquired pneumonia (CAP) is a leading cause of mortality worldwide, but disease burden of CAP is not clear so far. We aim to explore the spatial and temporal trends of mortality and years of life lost (YLL) due to CAP during 2013-2021 in mainland China, especially the mortality changes before and during COVID-19 pandemic due to COVID-19 related non-pharmaceutical interventions (NPIs).

Methods

We used data from the National Mortality Surveillance System to estimate the age-standardized rates of death and YLL of CAP at national and provincial level in China during 2013-2021. Monthly and provincial NPIs data were obtained from Oxford COVID-19 Government Response Tracker. The Average annual percentage change (AAPC) and mortality reduction were estimated by log-linear regression and interrupted time series, respectively.

Findings

In China, most CAP that caused deaths had no clear etiology, and bacterial pneumonia and viral pneumonia were the leading 2 causes among CAP deaths with determined etiology before and during COVID-19 pandemic. The age-standardized CAP mortality rate decreased from 11.18 per 100,000 in 2013 to 8.76 per 100,000 in 2019, and to 5.74 per 100,000 in 2021 (AAPC -4.51% vs -7.89%). Trends were similar in age-standardized rate of YLL. Both rates declined more for viral pneumonia, compared with bacterial pneumonia. After adjusting for NPIs at provincial level after 2020, the NPIs for COVID-19 was associated with significant reductions in CAP mortality (-0.34 per 100,000, -0.41 to -0.27; p < 0.0001), and provinces that economically developed and conducted strict regular NPIs against COVID-19 contributed the most reduction.

Interpretation

We observed a decreasing trend of age-standardized CAP mortality from 2013 to 2019, and a dramatical reduction during COVID-19 pandemic, especially for viral pneumonia. Our study provided the evidence for the effectiveness of regular NPIs on the significant reductions in CAP mortality.

Funding

This work has been supported by Beijing Municipal Science and Technology Project Z191100006619101, Chinese Academy of Medical Sciences (CAMS) Innovation Fund for Medical Sciences (CIFMS 2021-I2M-1-048), CAMS Institute of Respiratory Medicine Grant for Young Scholars (2023-ZF-8) and the New Cornerstone Science Foundation.

A Dataset and Model for the Visual Quality Assessment of Inversely Tone-Mapped HDR Videos

To enhance the viewer experience of standard dynamic range (SDR) video content on high dynamic range (HDR) displays, inverse tone mapping (ITM) is employed. Objective visual quality assessment (VQA) models are needed for effective evaluation of ITM algorithms. However, there is a lack of specialized VQA models for assessing the visual quality of inversely tone-mapped HDR videos (ITM-HDR-Videos). This paper addresses both an algorithmic and a dataset gap by introducing a novel SDR referenced HDR (SD-R-HD) VQA model tailored for ITM-HDR-Videos, along with the first public dataset specifically constructed for this purpose. The innovations of the SD-R-HD VQA model include 1) utilizing available SDR video as a reference signal, 2) extracting features that characterize standard ITM operations such as global mapping and local compensation, and 3) directly modeling interframe inconsistencies introduced by ITM operations. The newly created ITM-HDR-VQA dataset comprises 200 ITM-HDR-Videos annotated with mean opinion scores, gathered over 320 man-hours of psychovisual experiments. Experimental results demonstrate that the SD-R-HD VQA model significantly outperforms existing state-of-the-art VQA models.

Engineering RsDddA as mitochondrial base editor with wide target compatibility and enhanced activity

Double-stranded DNA-specific cytidine deaminase (DddA) base editors hold great promise for applications in bio-medical research, medicine, and biotechnology. Strict sequence preference on spacing region presents a challenge for DddA editors to reach their full potential. To overcome this sequence-context constraint, we analyzed a protein dataset and identified a novel DddAtox homolog from Ruminococcus sp. AF17-6 (RsDddA). We engineered RsDddA for mitochondrial base editing in a mammalian cell line and demonstrated RsDddA-derived cytosine base editors (RsDdCBE) offered a broadened NC sequence compatibility and exhibited robust editing efficiency. Moreover, our results suggest the average frequencies of mitochondrial genome-wide off-target editing arising from RsDdCBE are comparable to canonical DdCBE and its variants.

Efficacy and safety of anti-CD38 monoclonal antibodies in patients with relapsed/refractory multiple myeloma: a systematic review and meta-analysis with trial sequential analysis of randomized controlled trials

Objectives

The current study aims to evaluate the safety and efficacy of anti-CD38 monoclonal antibodies (mAbs) among patients with relapsed/refractory multiple myeloma (RRMM) through meta-analysis.

Methods

As of June 2023, we searched PubMed, Web of Science, Embase and the Cochrane Library. Randomized controlled trials (RCTs) which compared the clinical outcomes of anti-CD38 mAbs plus immunomodulatory drugs (IMiDs) or proteasome inhibitors (PIs) plus dexamethasone and IMiDs (or PIs) and dexamethasone alone for RRMM patients were included. Efficacy outcomes were mainly evaluated with progression-free survival (PFS) and overall survival (OS). The safety was analyzed with hematologic and nonhematologic treatment-emergent adverse events (TEAEs). All results were pooled using hazard ratio (HR), relative risk (RR), and their 95% confidence interval (CI) and prediction interval (PI).

Results

This meta-analysis included 11 RCTs in total. Compared with IMiDs (or PIs) and dexamethasone alone, anti-CD38 mAbs in combination with IMiDs (or PIs) and dexamethasone significantly prolonged PFS (HR: 0.552, 95% CI = 0.461 to 0.659, 95% PI = 0.318 to 0.957) and OS (HR: 0.737, 95% CI = 0.657 to 0.827, 95% PI = 0.626 to 0.868) in patients with RRMM. Additionally, RRMM patients receiving anti-CD38 mAbs in combination with IMiDs (or PIs) and dexamethasone achieved higher rates of overall response (RR: 1.281, 95% CI = 1.144 to 1.434, 95% PI = 0.883 to 1.859), complete response or better (RR: 2.602, 95% CI = 1.977 to 3.424, 95% PI = 1.203 to 5.628), very good partial response (VGPR) or better (RR: 1.886, 95% CI = 1.532 to 2.322, 95% PI = 0.953 to 3.731), and minimum residual disease (MRD)-negative (RR: 4.147, 95% CI = 2.588 to 6.644, 95% PI = 1.056 to 16.283) than those receiving IMiDs (or PIs) and dexamethasone alone. For TEAEs, the rates of hematologic and nonhematologic TEAEs, including thrombocytopenia, neutropenia, upper respiratory tract infection (URTI), pneumonia, bronchitis, dyspnea, diarrhea, pyrexia, back pain, arthralgia, fatigue, insomnia, and hypertension, were higher in the anti-CD38 mAbs in combination with IMiDs (or PIs) and dexamethasone group than in the IMiDs (or PIs) and dexamethasone group.

Conclusion

Our study showed that anti-CD38 mAbs in combination with IMiDs (or PIs) and dexamethasone improved PFS and OS, and achieved higher rates of overall response, complete response or better, VGPR or better, and MRD-negative, as well as higher rates of thrombocytopenia, neutropenia, URTI, pneumonia, bronchitis, dyspnea, diarrhea, pyrexia, back pain, arthralgia, fatigue, insomnia, and hypertension in RRMM patients.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023431071.

Air bronchogram on chest CT in radiological pure-solid appearance lung cancer: Correlation analysis with genetic pathological features and survival outcomes

PURPOSE

To investigate the correlation of air bronchogram sign with clinicopathological characteristics and prognosis in patients with clinical stage (c-stage) I non-small cell lung cancer (NSCLC) with radiological pure-solid appearance.

METHOD

We retrospectively evaluated 276 patients with pure-solid c-stage I NSCLC and assessed the correlation between the air bronchogram and clinicopathological characteristics. A Cox proportional hazards model was performed to identify the effect of air bronchogram and clinicopathological variables on oncological outcomes. Recurrence-free survival (RFS) and overall survival (OS) were calculated by Kaplan-Meier curves and were compared using log-rank tests.

RESULTS

Presence of air bronchogram was associated with a well differentiated degree (P =.026), higher incidence of EGFR mutation (P <.001) and lower recurrence(P =.021). Kaplan-Meier survival curves showed that air bronchogram group was associated with favorable RFS(67.0% vs. 50.2%; P =.015). A multivariable analysis revealed that air bronchogram and EGFR mutation were independent significant prognostic factors associated with RFS (hazard ratio [HR] = 0.495, 95% confidence interval [CI]: 0.322-0.761, P =.001; HR = 1.625, 95% CI: 1.074-2.457, P =.021; respectively), but not with OS. Additionally, we found that pathological lymph node metastasis was identified as an independent prognostic factor associated with poor RFS and OS(HR = 2.808, 95% CI: 1.913-4.123, P <.001 for RFS; HR = 1.983, 95% CI: 1.185-3.318, P =.009 for OS).

CONCLUSIONS

Presence of air bronchogram was associated with well differentiated degree, higher incidence of EGFR mutation and had additional positive prognostic value for RFS in c-stage I NSCLC with a radiological pure-solid appearance.

LncRNA H19-EZH2 interaction promotes liver fibrosis via reprogramming H3K27me3 profiles

Liver fibrosis is a wound-healing process characterized by excess formation of extracellular matrix (ECM) from activated hepatic stellate cells (HSCs). Previous studies show that both EZH2, an epigenetic regulator that catalyzes lysine 27 trimethylation on histone 3 (H3K27me3), and long non-coding RNA H19 are highly correlated with fibrogenesis. In the current study, we investigated the underlying mechanisms. Various models of liver fibrosis including Mdr2-/-, bile duct ligation (BDL) and CCl4 mice were adapted. We found that EZH2 was markedly upregulated and correlated with H19 and fibrotic markers expression in these models. Administration of EZH2 inhibitor 3-DZNeP caused significant protective effects in these models. Furthermore, treatment with 3-DZNeP or GSK126 significantly inhibited primary HSC activation and proliferation in TGF-β-treated HSCs and H19-overexpreesing LX2 cells in vivo. Using RNA-pull down assay combined with RNA immunoprecipitation, we demonstrated that H19 could directly bind to EZH2. Integrated analysis of RNA-sequencing (RNA-seq) and chromatin immunoprecipitation sequencing (ChIP-seq) further revealed that H19 regulated the reprogramming of EZH2-mediated H3K27me3 profiles, which epigenetically promoted several pathways favoring HSCs activation and proliferation, including epithelial-mesenchymal transition and Wnt/β-catenin signaling. In conclusion, highly expressed H19 in chronic liver diseases promotes fibrogenesis by reprogramming EZH2-mediated epigenetic regulation of HSCs activation. Targeting the H19-EZH2 interaction may serve as a novel therapeutic approach for liver fibrosis.

The effectiveness of needle aspiration versus traditional incision and drainage in the treatment of breast abscess: a meta-analysis

BACKGROUND

Breast abscess is a common and intractable clinical condition and the use of needle aspiration (NA) or incision and drainage (ID) in treatment is controversial. This meta-analysis aimed to systematically compare the clinical effectiveness of NA and ID in treating breast abscesses.

METHODS

The Web of Science, ScienceDirect, PubMed, Cochrane Library, EMBASE, China National Knowledge Infrastructure, and Wanfang Data were searched for randomized controlled trials (RCTs) published from inception to January 7, 2022. The ROB-2 tool assessed risk of bias; the GRADE methodology rated certainty in outcomes; and Stata 16.0 performed data analyses.

RESULTS

Nine RCTs were included, including 703 patients. The results showed there was no significant difference in cure rate between the two groups (relative risk [RR] = 0.96, 95% confidence interval [CI] [0.86, 1.07]; p = .469), and after subgroup analysis, we found that it was not related to the use of ultrasound guidance or not. There was no significant difference in the recurrence rate (RR = 0.68, 95% CI [0.35, 1.30]; p = .241). Furthermore, the NA group was associated with shorter healing time (weighted mean differences = -11.02, 95% CI [-15.14, -6.90]; p < .001), lower incidence of breast fistula (RR = 0.21, 95% CI [0.06, 0.72]; p = .013), lower interrupted breastfeeding rate (RR = 0.28, 95% CI [0.20, 0.39]; p < .001), and higher satisfaction rate of appearance (RR = 1.51, 95% CI [1.03-2.21]; p = .035).

CONCLUSION

NA has better advantages in terms of healing time, avoidance of breast fistula, continuous breastfeeding, and patient satisfaction. Although NA and ID have similar cure and recurrence rates, NA, with or without ultrasound guidance, could be used as a first-line treatment for breast abscesses. Patients with large volumes, multicompartmental abscesses, or those who have been ineffective against multiple NA, should be considered for ID.KEY MESSAGESBreast abscess is a common and intractable clinical condition in general surgery.Compared with ID for breast abscesses, NA has better advantages in terms of healing time, avoidance of breast fistula, continuous breastfeeding, and patient satisfaction and could be used as a first-line treatment for breast abscesses.Patients with large volumes, multicompartmental abscesses, or those who have been ineffective against multiple NA, should be considered for ID.

H3K27 acetylation activated-CD109 evokes 5-fluorouracil resistance in gastric cancer via the JNK/MAPK signaling pathway

Drug resistance is a considerable obstacle to gastric cancer (GC) treatment. The current work aimed to elucidate the functional mechanism of CD109 in 5-fluorouracil (5-FU) resistance in GC. In this study, we demonstrated that CD109 was extremely heightened in 5-FU-resistant GC cells. CD109 deficiency lessened the IC50 value, impaired cell viability and metastatic capability, and induced cell apoptosis after 5-FU treatment in cells. In addition, we found that PAX5 bound p300 increased the enrichment of H3K27ac at the promoter region of the CD109 gene, which resulted in the upregulation of CD109 in GC. Moreover, we also revealed that CD109 triggered 5-FU resistance via activating the JNK/MAPK signaling. Blockage of JNK/MAPK signaling using JNK inhibitor, SP600125, abolished CD109 upregulation-induced changes of IC50 values, cell viability, metastasis and apoptosis in NCI-N87/5-FU and SNU-1/5-FU cells. Importantly, CD109 silencing enhanced the therapeutic efficacy of 5-FU, leading to reduced tumor growth in vivo. In conclusion, our results unveiled that H3K27 acetylation activated-CD109 enhanced 5-FU resistance of GC cells via modulating the JNK/MAPK signaling pathway, which might provide an attractive therapeutic target for GC.

Recent advances and applications of laser-based imaging techniques in food crops and products: a critical review

To meet the growing demand for food quality and safety, there is a pressing need for fast and visible techniques to monitor the food crop and product production processing, and to understand the chemical changes that occur during these processes. Herein, the fundamental principles, instruments, and characteristics of three major laser-based imaging techniques (LBITs), namely, laser-induced breakdown spectroscopy, Raman spectroscopy, and laser ablation-inductively coupled plasma-mass spectrometry, are introduced. Additionally, the advances, challenges, and prospects for the application of LBITs in food crops and products are discussed. In recent years, LBITs have played a crucial role in mapping primary metabolites, secondary metabolites, nanoparticles, toxic metals, and mineral elements in food crops, as well as visualizing food adulteration, composition changes, pesticide residue, microbial contamination, and elements in food products. However, LBITs are still facing challenges in achieving accurate and sensitive quantification of compositions due to the complex sample matrix and minimal laser sampling quantity. Thus, further research is required to develop comprehensive data processing strategies and signal enhancement methods. With the continued development of imaging methods and equipment, LBITs have the potential to further explore chemical distribution mechanisms and ensure the safety and quality of food crops and products.

Integrative risk assessment method via combining geostatistical analysis, random forest, and receptor models for potentially toxic elements in selenium-rich soil

Revealing the spatial features and source of associated potentially toxic elements (PTEs) is crucial for the safe use of selenium (Se)-rich soils. An integrative risk assessment (GRRRA) approach based on geostatistical analysis (GA), random forest (RF), and receptor models (RMs) was first established to investigate the spatial distribution, sources, and potential ecological risks (PER) of PTEs in 982 soils from Ziyang City, a typical natural Se-rich area in China. RF combined with multiple RMs supported the source apportionment derived from the RMs and provided accurate results for source identification. Then, quantified source contributions were introduced into the risk assessment. Eighty-three percent of the samples contain Cd at a high PER level in local Se-rich soils. GA based on spatial interpolation and spatial autocorrelation showed that soil PTEs have distinct spatial characteristics, and high values are primarily distributed in this research areas. Absolute principal component score/multiple line regression (APCS/MLR) is more suitable than positive matrix factorization (PMF) for source apportionment in this study. RF combined with RMs more accurately and scientifically extracted four sources of soil PTEs: parent material (48.91%), mining (17.93%), agriculture (8.54%), and atmospheric deposition (24.63%). Monte Carlo simulation (MCS) demonstrates a 47.73% probability of a non-negligible risk (RI > 150) caused by parent material and 3.6% from industrial sources, respectively. Parent material (64.20%, RI = 229.56) and mining (16.49%, RI = 58.96) sources contribute to the highest PER of PTEs. In conclusion, the GRRRA method can comprehensively analyze the distribution and sources of soil PTEs and effectively quantify the source contribution to PER, thus providing the theoretical foundation for the secure utilization of Se-rich soils and environmental management and decision making.

Cryo-EM structures of human magnesium channel MRS2 reveal gating and regulatory mechanisms

Magnesium ions (Mg2+) play an essential role in cellular physiology. In mitochondria, protein and ATP synthesis and various metabolic pathways are directly regulated by Mg2+. MRS2, a magnesium channel located in the inner mitochondrial membrane, mediates the influx of Mg2+ into the mitochondrial matrix and regulates Mg2+ homeostasis. Knockdown of MRS2 in human cells leads to reduced uptake of Mg2+ into mitochondria and disruption of the mitochondrial metabolism. Despite the importance of MRS2, the Mg2+ translocation and regulation mechanisms of MRS2 are still unclear. Here, using cryo-EM we report the structures of human MRS2 in the presence and absence of Mg2+ at 2.8 Å and 3.3 Å, respectively. From the homo-pentameric structures, we identify R332 and M336 as major gating residues, which are then tested using mutagenesis and two cellular divalent ion uptake assays. A network of hydrogen bonds is found connecting the gating residue R332 to the soluble domain, potentially regulating the gate. Two Mg2+-binding sites are identified in the MRS2 soluble domain, distinct from the two sites previously reported in CorA, a homolog of MRS2 in prokaryotes. Altogether, this study provides the molecular basis for understanding the Mg2+ translocation and regulatory mechanisms of MRS2.

Magnetic-field-induced splitting of Rydberg Electromagnetically Induced Transparency and Autler-Townes spectra in 87Rb vapor cell

We theoretically and experimentally investigate the Rydberg electromagnetically induced transparency (EIT) and Autler-Townes (AT) splitting of 87Rb vapor under the combined influence of a magnetic field and a microwave field. In the presence of static magnetic field, the effect of the microwave field leads to the dressing and splitting of each mF state, resulting in multiple spectral peaks in the EIT-AT spectrum. A simplified analytical formula was developed to explain the EIT-AT spectrum in a static magnetic field, and the theoretical calculations agree qualitatively with experimental results. The Rydberg atom microwave electric field sensor performance was enhanced by making use of the splitting interval between the two maximum absolute mF states separated by the static magnetic field, which was attributed to the stronger Clebsch-Gordon coefficients between the extreme mF states and the frequency detuning of the microwave electric field under the static magnetic field. The traceable measurement limit of weak electric field by EIT-AT splitting method was extended by an order of magnitude, which is promising for precise microwave electric field measurement.

Early C-reactive Protein Kinetics Predict Response to Immune Checkpoint Blockade in Unresectable Hepatocellular Carcinoma

Purpose

In recent years, a new therapeutic approach, known as immune checkpoint blockade (ICB), has been proposed as approach to improve outcomes in patients with intermediate stage (Barcelona Clinic Liver Cancer, BCLC B) or advanced stage (BCLC C) hepatocellular carcinoma (HCC). Unfortunately, only a select patients can benefit from ICB. Hence, biomarkers that can predict the success and survival of treatment are still necessary.

Patients and Methods

Between 2018 to 2021, 132 patients received ICB treatment for intermediate or advanced stage HCC. Based on the early kinetics of C-reactive protein (CRP), the patients were classified into three groups. The study endpoints were progression-free survival (PFS) and overall survival (OS).

Results

Our findings support the predictive power of early CRP kinetics in determining immunotherapy response for intermediate or advanced HCC. Objective response rates (ORR) were found in 41.2% of CRP flare-responders, 13.3% of CRP responders, and 3.5% of CRP non-responders (p<0.001). Disease control rates (DCR) in the three groups were substantially different (p<0.001). The improved PFS and OS were strongly correlated with the early kinetics of CRP. Compared to CRP non-responders, CRP responders, especially CRP flare-responders, had significantly longer PFS (median PFS: CRP flare-responders: 11.6 months vs CRP responders: 5.2 months vs CRP non-responders: 2.3 months, p<0.001).

Conclusion

The CRP flare response robustly predicts the immunotherapy response and outcomes in patients with HCC. Early CRP kinetics may be an inexpensive, easily implemented and non-invasive biomarker to anticipate response to ICB therapy in intermediate or advanced HCC, with the potential to optimize treatment monitoring.

Glutamate secretion by embryonic stem cells as an autocrine signal to promote proliferation

Glutamate, the major excitatory neurotransmitter in the central nervous system, has also been found to play a role in embryonic stem (ES) cells. However, the exact mechanism and function of glutamatergic signaling in ES cells remain poorly understood. In this study, we identified a glutamatergic transmission circuit in ES cells that operates through an autocrine mechanism and regulates cell proliferation. We performed biological analyses to identify the key components involved in glutamate biosynthesis, packaging for secretion, reaction, and reuptake in ES cells, including glutaminase, vesicular glutamate transporter, glutamate N-methyl-D-aspartate (NMDA) receptor, and cell membrane excitatory amino-acid transporter (EAAT). We directly quantified the released glutamate signal using microdialysis-high performance liquid chromatography-tandem mass spectrometry (MD-HPLC-MS-MS). Pharmacological inhibition of endogenous glutamate release and the resulting tonic activation of NMDA receptors significantly affected ES cell proliferation, suggesting that ES cells establish a glutamatergic autocrine niche via releasing and responding to the transmitter for their own regulation.

Inhibiting autophagy to boost antitumor immunity with tetramethylpyrazine-loaded and PD-L1-targeting liposomal nanoparticles

Cancer immunotherapy has been recognized as a revolutionary breakthrough and has yielded impressive results. However, a major challenge facing immunotherapy is its limited efficacy, which may be largely due to the inadequate infiltration of immune cells into the tumor microenvironment (TME). Autophagy inhibition has been identified to enhance the recruitment of immune cells into the tumor by upregulating the expression and secretion of chemokines. Here, we verified a novel autophagy inhibitor tetramethylpyrazine (TMP) from natural products using a mCherry-GFP-LC3 probe-based autophagy flux reporter system. We then devised a liposomal system capable of co-delivering DOX and TMP using the thin-film dispersion method and modified the liposome with PD-L1 binding peptide JY4 (DOX-TMP-JY4LIPO). We found that DOX-TMP-JY4LIPO exhibited potent antitumor efficacy in vitro. In addition, DOX-TMP-JY4LIPO could effectively inhibit the autophagic flux to enhance the recruitment of immune cells into the tumor by upregulating CCL5 and CXCL10. The liposome exhibited favorable biocompatibility and safety while facilitating the accumulation of therapeutic drugs in tumors. DOX-TMP-JY4LIPO significantly inhibited tumor growth in LLC xenograft mice, accompanied by increased granzymes- and perforin-mediated cytotoxic immune responses. Our findings demonstrate that the TMP-loaded and PD-L1-targeting liposomal nanoparticles can significantly boost antitumor immunity by inhibiting autophagy, suggesting a novel natural product-based nanomedicine for immunotherapy.

Structure-function analyses reveal key molecular determinants of HIV-1 CRF01_AE resistance to the entry inhibitor temsavir

The HIV-1 entry inhibitor temsavir prevents the viral receptor CD4 (cluster of differentiation 4) from interacting with the envelope glycoprotein (Env) and blocks its conformational changes. To do this, temsavir relies on the presence of a residue with small side chain at position 375 in Env and is unable to neutralize viral strains like CRF01_AE carrying His375. Here we investigate the mechanism of temsavir resistance and show that residue 375 is not the sole determinant of resistance. At least six additional residues within the gp120 inner domain layers, including five distant from the drug-binding pocket, contribute to resistance. A detailed structure-function analysis using engineered viruses and soluble trimer variants reveals that the molecular basis of resistance is mediated by crosstalk between His375 and the inner domain layers. Furthermore, our data confirm that temsavir can adjust its binding mode to accommodate changes in Env conformation, a property that likely contributes to its broad antiviral activity.

Developing mitochondrial base editors with diverse context compatibility and high fidelity via saturated spacer library

DddA-derived cytosine base editors (DdCBEs) greatly facilitated the basic and therapeutic research of mitochondrial DNA mutation diseases. Here we devise a saturated spacer library and successfully identify seven DddA homologs by performing high-throughput sequencing based screen. DddAs of Streptomyces sp. BK438 and Lachnospiraceae bacterium sunii NSJ-8 display high deaminase activity with a strong GC context preference, and DddA of Ruminococcus sp. AF17-6 is highly compatible to AC context. We also find that different split sites result in wide divergence on off-target activity and context preference of DdCBEs derived from these DddA homologs. Additionally, we demonstrate the orthogonality between DddA and DddIA, and successfully minimize the nuclear off-target editing by co-expressing corresponding nuclear-localized DddIA. The current study presents a comprehensive and unbiased strategy for screening and characterizing dsDNA cytidine deaminases, and expands the toolbox for mtDNA editing, providing additional insights for optimizing dsDNA base editors.

Exploration of Solid Solutions and the Strengthening of Aluminum Substrates by Alloying Atoms: Machine Learning Accelerated Density Functional Theory Calculations

In this paper, we studied the effects of a series of alloying atoms on the stability and micromechanical properties of aluminum alloy using a machine learning accelerated first-principles approach. In our preliminary work, high-throughput first-principles calculations were explored and the solution energy and theoretical stress of atomically doped aluminum substrates were extracted as basic data. By comparing five different algorithms, we found that the Catboost model had the lowest RMSE (0.24) and lowest MAPE (6.34), and this was used as the final prediction model to predict the solid solution strengthening of the aluminum matrix by the elements. Calculations show that alloying atoms such as K, Na, Y and Tl are difficult to dissolve in the aluminum matrix, whereas alloy atoms like Sc, Cu, B, Zr, Ni, Ti, Nb, V, Cr, Mn, Mo, and W exerted a strengthening influence. Theoretical studies on solid solutions and the strengthening effect of various alloy atoms in an aluminum matrix can offer theoretical guidance for the subsequent selection of suitable alloy elements. The theoretical investigation of alloy atoms in an aluminum matrix unveils the fundamental aspects of the solution strengthening effect, contributing significantly to the expedited development of new aluminum alloys.