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1.
Cell ; 187(5): 1127-1144.e21, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38428393

ABSTRACT

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.


Subject(s)
DNA-Directed RNA Polymerases , Plastids , Chloroplasts/metabolism , Cryoelectron Microscopy , DNA-Directed RNA Polymerases/genetics , Nicotiana/genetics , Photosynthesis , Plastids/enzymology
2.
Nature ; 589(7841): 214-219, 2021 01.
Article in English | MEDLINE | ID: mdl-33408416

ABSTRACT

Quantum key distribution (QKD)1,2 has the potential to enable secure communication and information transfer3. In the laboratory, the feasibility of point-to-point QKD is evident from the early proof-of-concept demonstration in the laboratory over 32 centimetres4; this distance was later extended to the 100-kilometre scale5,6 with decoy-state QKD and more recently to the 500-kilometre scale7-10 with measurement-device-independent QKD. Several small-scale QKD networks have also been tested outside the laboratory11-14. However, a global QKD network requires a practically (not just theoretically) secure and reliable QKD network that can be used by a large number of users distributed over a wide area15. Quantum repeaters16,17 could in principle provide a viable option for such a global network, but they cannot be deployed using current technology18. Here we demonstrate an integrated space-to-ground quantum communication network that combines a large-scale fibre network of more than 700 fibre QKD links and two high-speed satellite-to-ground free-space QKD links. Using a trusted relay structure, the fibre network on the ground covers more than 2,000 kilometres, provides practical security against the imperfections of realistic devices, and maintains long-term reliability and stability. The satellite-to-ground QKD achieves an average secret-key rate of 47.8 kilobits per second for a typical satellite pass-more than 40 times higher than achieved previously. Moreover, its channel loss is comparable to that between a geostationary satellite and the ground, making the construction of more versatile and ultralong quantum links via geosynchronous satellites feasible. Finally, by integrating the fibre and free-space QKD links, the QKD network is extended to a remote node more than 2,600 kilometres away, enabling any user in the network to communicate with any other, up to a total distance of 4,600 kilometres.

3.
Plant Cell ; 35(2): 795-807, 2023 02 20.
Article in English | MEDLINE | ID: mdl-36471570

ABSTRACT

Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) performs most of the carbon fixation on Earth. However, plant Rubisco is an intrinsically inefficient enzyme given its low carboxylation rate, representing a major limitation to photosynthesis. Replacing endogenous plant Rubisco with a faster Rubisco is anticipated to enhance crop photosynthesis and productivity. However, the requirement of chaperones for Rubisco expression and assembly has obstructed the efficient production of functional foreign Rubisco in chloroplasts. Here, we report the engineering of a Form 1A Rubisco from the proteobacterium Halothiobacillus neapolitanus in Escherichia coli and tobacco (Nicotiana tabacum) chloroplasts without any cognate chaperones. The native tobacco gene encoding Rubisco large subunit was genetically replaced with H. neapolitanus Rubisco (HnRubisco) large and small subunit genes. We show that HnRubisco subunits can form functional L8S8 hexadecamers in tobacco chloroplasts at high efficiency, accounting for ∼40% of the wild-type tobacco Rubisco content. The chloroplast-expressed HnRubisco displayed a ∼2-fold greater carboxylation rate and supported a similar autotrophic growth rate of transgenic plants to that of wild-type in air supplemented with 1% CO2. This study represents a step toward the engineering of a fast and highly active Rubisco in chloroplasts to improve crop photosynthesis and growth.


Subject(s)
Nicotiana , Ribulose-Bisphosphate Carboxylase , Nicotiana/metabolism , Ribulose-Bisphosphate Carboxylase/genetics , Ribulose-Bisphosphate Carboxylase/metabolism , Photosynthesis/genetics , Chloroplasts/metabolism , Plants, Genetically Modified/metabolism , Carbon Dioxide/metabolism
4.
Plant Cell ; 35(6): 2293-2315, 2023 05 29.
Article in English | MEDLINE | ID: mdl-36929908

ABSTRACT

Terpenoids constitute the largest class of plant primary and secondary metabolites with a broad range of biological and ecological functions. They are synthesized from isopentenyl diphosphate and dimethylallyl diphosphate, which in plastids are condensed by geranylgeranyl diphosphate synthases (GGPPSs) to produce GGPP (C20) for diterpene biosynthesis and by geranyl diphosphate synthases (GPPSs) to form GPP (C10) for monoterpene production. Depending on the plant species, unlike homomeric GGPPSs, GPPSs exist as homo- and heteromers, the latter of which contain catalytically inactive GGPPS-homologous small subunits (SSUs) that can interact with GGPPSs. By combining phylogenetic analysis with functional characterization of GGPPS homologs from a wide range of photosynthetic organisms, we investigated how different GPPS architectures have evolved within the GGPPS protein family. Our results reveal that GGPPS gene family expansion and functional divergence began early in nonvascular plants, and that independent parallel evolutionary processes gave rise to homomeric and heteromeric GPPSs. By site-directed mutagenesis and molecular dynamics simulations, we also discovered that Leu-Val/Val-Ala pairs of amino acid residues were pivotal in the functional divergence of homomeric GPPSs and GGPPSs. Overall, our study elucidated an evolutionary path for the formation of GPPSs with different architectures from GGPPSs and uncovered the molecular mechanisms involved in this differentiation.


Subject(s)
Dimethylallyltranstransferase , Diterpenes , Farnesyltranstransferase/genetics , Farnesyltranstransferase/metabolism , Phylogeny , Dimethylallyltranstransferase/genetics , Dimethylallyltranstransferase/metabolism , Diterpenes/metabolism
5.
J Biol Chem ; 299(7): 104860, 2023 07.
Article in English | MEDLINE | ID: mdl-37236355

ABSTRACT

Among the various components of the protozoan Plasmodium mitochondrial respiratory chain, only Complex III is a validated cellular target for antimalarial drugs. The compound CK-2-68 was developed to specifically target the alternate NADH dehydrogenase of the malaria parasite respiratory chain, but the true target for its antimalarial activity has been controversial. Here, we report the cryo-EM structure of mammalian mitochondrial Complex III bound with CK-2-68 and examine the structure-function relationships of the inhibitor's selective action on Plasmodium. We show that CK-2-68 binds specifically to the quinol oxidation site of Complex III, arresting the motion of the iron-sulfur protein subunit, which suggests an inhibition mechanism similar to that of Pf-type Complex III inhibitors such as atovaquone, stigmatellin, and UHDBT. Our results shed light on the mechanisms of observed resistance conferred by mutations, elucidate the molecular basis of the wide therapeutic window of CK-2-68 for selective action of Plasmodium vs. host cytochrome bc1, and provide guidance for future development of antimalarials targeting Complex III.


Subject(s)
Antimalarials , Plasmodium , Animals , Antimalarials/chemistry , Electron Transport Complex III/metabolism , Plasmodium falciparum/metabolism , Plasmodium/metabolism , Cytochromes/metabolism , Mammals/metabolism
6.
Anal Chem ; 96(39): 15665-15673, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39298294

ABSTRACT

Tumor-derived small extracellular vesicle (sEV) microRNAs (miRNAs) are emerging biomarkers for cancer diagnostics. Conventional sEV miRNA detection methods necessitate the lysis of sEVs, rendering them laborious and time-consuming and potentially leading to damage or loss of miRNAs. Membrane fusion-based in situ detection of sEV miRNAs involves the preparation of probe-loaded vesicles (e.g., liposomes or cellular vesicles), which are typically sophisticated and require specialist equipment. Membrane perforation methods employ chemical treatments that can induce severe miRNA degradation or leaks. Inspired by previous studies that loaded nucleic acids into EVs or cells using hydrophobic tethers for therapeutic applications, herein, we repurposed this strategy by conjugating a hydrophobic tether onto molecular beacons to aid their transportation into sEVs, allowing for in situ detection of miRNAs in a fusion-free and multiplexing manner. This method enables simultaneous detection of multiple miRNA species within serum-derived sEVs for the diagnosis of prostate cancer, breast cancer, and gastric cancer with an accuracy of 83.3%, 81.8%, and 100%, respectively, in a cohort of 66 individuals, indicating that it holds a high application potential in clinical diagnostics.


Subject(s)
Extracellular Vesicles , MicroRNAs , Humans , Extracellular Vesicles/chemistry , Extracellular Vesicles/metabolism , MicroRNAs/analysis , Female , Male , Biomarkers, Tumor/analysis , Neoplasms/diagnosis , Neoplasms/genetics , Breast Neoplasms/diagnosis , Prostatic Neoplasms/diagnosis
7.
Chembiochem ; 25(13): e202400227, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38700476

ABSTRACT

Biomarkers are crucial physiological and pathological indicators in the host. Over the years, numerous detection methods have been developed for biomarkers, given their significant potential in various biological and biomedical applications. Among these, the detection system based on functionalized DNA origami has emerged as a promising approach due to its precise control over sensing modules, enabling sensitive, specific, and programmable biomarker detection. We summarize the advancements in biomarker detection using functionalized DNA origami, focusing on strategies for DNA origami functionalization, mechanisms of biomarker recognition, and applications in disease diagnosis and monitoring. These applications are organized into sections based on the type of biomarkers - nucleic acids, proteins, small molecules, and ions - and concludes with a discussion on the advantages and challenges associated with using functionalized DNA origami systems for biomarker detection.


Subject(s)
Biomarkers , DNA , DNA/chemistry , DNA/analysis , Biomarkers/analysis , Humans , Biosensing Techniques , Nanostructures/chemistry , Proteins/analysis , Proteins/chemistry , Nucleic Acid Conformation
8.
Phys Rev Lett ; 132(26): 260802, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38996307

ABSTRACT

Twin-field quantum key distribution (TFQKD) overcomes the linear rate-loss limit, which promises a boost of secure key rate over long distance. However, the complexity of eliminating the frequency differences between the independent laser sources hinders its practical application. We analyzed and determined the frequency stability requirements for implementing TFQKD using frequency-stabilized lasers. Based on this analysis, we proposed and demonstrated a simple and practical approach that utilizes the saturated absorption spectroscopy of acetylene as an absolute reference, eliminating the need for fast frequency locking to achieve TFQKD. Adopting the 4-intensity sending-or-not-sending TFQKD protocol, we experimentally demonstrated the TFQKD over 502, 301, and 201 km ultralow-loss optical fiber, respectively. We expect this high-performance scheme will find widespread usage in future intercity and free-space quantum communication networks.

9.
J Med Primatol ; 53(1): e12688, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38083989

ABSTRACT

BACKGROUND: The significantly increasing incidence of type 2 diabetes mellitus (T2DM) over the last few decades triggers the demands of T2DM animal models to explore the pathogenesis, prevention, and therapy of the disease. The altered lipid metabolism may play an important role in the pathogenesis and progression of T2DM. However, the characterization of molecular lipid species in fasting serum related to T2DM cynomolgus monkeys is still underrecognized. METHODS: Untargeted and targeted LC-mass spectrometry (MS)/MS-based lipidomics approaches were applied to characterize and compare the fasting serum lipidomic profiles of T2DM cynomolgus monkeys and the healthy controls. RESULTS: Multivariate analysis revealed that 196 and 64 lipid molecules differentially expressed in serum samples using untargeted and targeted lipidomics as the comparison between the disease group and healthy group, respectively. Furthermore, the comparative analysis of differential serum lipid metabolites obtained by untargeted and targeted lipidomics approaches, four common serum lipid species (phosphatidylcholine [18:0_22:4], lysophosphatidylcholine [14:0], phosphatidylethanolamine [PE] [16:1_18:2], and PE [18:0_22:4]) were identified as potential biomarkers and all of which were found to be downregulated. By analyzing the metabolic pathway, glycerophospholipid metabolism was associated with the pathogenesis of T2DM cynomolgus monkeys. CONCLUSION: The study found that four downregulated serum lipid species could serve as novel potential biomarkers of T2DM cynomolgus monkeys. Glycerophospholipid metabolism was filtered out as the potential therapeutic target pathway of T2DM progression. Our results showed that the identified biomarkers may offer a novel tool for tracking disease progression and response to therapeutic interventions.


Subject(s)
Diabetes Mellitus, Type 2 , Animals , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/metabolism , Lipidomics/methods , Macaca fascicularis , Biomarkers , Lipids , Glycerophospholipids
10.
AJR Am J Roentgenol ; 223(2): e2431283, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38809121

ABSTRACT

BACKGROUND. The presence of a ground-glass opacity (GGO) component is a favorable prognostic factor in non-small cell lung cancer (NSCLC), although the prognostic impact of a very small GGO component remains poorly investigated. OBJECTIVE. The purpose of this article is to investigate the impact of a minor (≤ 10%) GGO component on the prognosis of clinical stage I NSCLC in comparison with pure-solid nodules. METHODS. This retrospective study included 382 patients (mean age, 60.8 years; 210 men, 172 women) who underwent surgical resection between January 1, 2015, and December 31, 2015, for clinical stage I NSCLC appearing on preoperative chest CT as a nodule with a consolidation-to-tumor ratio (CTR) of 0.9 to 1.0. Two radiologists independently assigned nodules to groups as either minor GGO (CTR, ≥ 0.9 and < 1.0) or pure solid (CTR = 1.0). Recurrence-free survival (RFS) and cancer-specific survival (CSS) were assessed by Kaplan-Meier curves and compared between groups using log-rank tests. Cox proportional hazards models were used to assess associations with outcomes. RESULTS. The two radiologists agreed for all nodules' classification into the minor-GGO (n = 106) or pure-solid (n = 276) groups. The mean CTR of the minor-GGO group was 0.93 ± 0.02 (SD) (range, 0.90-0.97). Minor-GGO nodules, in comparison with pure-solid nodules, showed greater solid-component diameter (2.68 vs 2.16 cm; p < .001) and total nodule diameter (2.89 vs 2.16 cm; p < .001). The minor-GGO group, in comparison with the pure-solid group, showed lower frequencies of visceral pleural invasion (6.6% vs 17.0%, p = .009) and pathologic lymph node involvement (4.7% vs 20.3%, p < .001), and EGFR mutation (71.6% vs 39.9%; p < .001). The minor-GGO group, in comparison with the pure-solid group, showed better 5-year RFS (83.4% vs 55.0%; p < .001) and higher frequency of better 5-year CSS (92.4% vs 76.4%, p = .004). In multivariable analysis adjusting for patient, imaging, pathologic, and genetic factors, a minor-GGO component was independently associated with a decreased likelihood of recurrence (HR = 0.37, p = .001) but not with the likelihood of CSS. CONCLUSION. Among patients with clinical stage I NSCLC, cancers with a minor-GGO component were associated with a better prognosis versus those with a pure-solid appearance. CLINICAL IMPACT. Radiologists encountering predominantly solid nodules on CT should carefully assess images for even a minor-GGO component given the favorable prognosis.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Neoplasm Staging , Tomography, X-Ray Computed , Humans , Male , Female , Middle Aged , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/pathology , Lung Neoplasms/surgery , Carcinoma, Non-Small-Cell Lung/diagnostic imaging , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/surgery , Retrospective Studies , Tomography, X-Ray Computed/methods , Aged , Prognosis , Adult , Aged, 80 and over
11.
J Chem Inf Model ; 64(16): 6369-6376, 2024 Aug 26.
Article in English | MEDLINE | ID: mdl-39183596

ABSTRACT

Accurate identification of ice phases is essential for understanding various physicochemical phenomena. However, such classification for structures simulated with molecular dynamics is complicated by the complex symmetries of ice polymorphs and thermal fluctuations. For this purpose, both traditional order parameters and data-driven machine learning approaches have been employed, but they often rely on expert intuition, specific geometric information, or large training data sets. In this work, we present an unsupervised phase classification framework that combines a score-based denoiser model with a subsequent model-free classification method to accurately identify ice phases. The denoiser model is trained on perturbed synthetic data of ideal reference structures, eliminating the need for large data sets and labeling efforts. The classification step utilizes the smooth overlap of atomic position (SOAP) descriptors as the atomic fingerprint, ensuring Euclidean symmetries and transferability to various structural systems. Our approach achieves a remarkable 100% accuracy in distinguishing ice phases of test trajectories using only seven ideal reference structures of ice phases as model inputs. This demonstrates the generalizability of the score-based denoiser model in facilitating phase identification for complex molecular systems. The proposed classification strategy can be broadly applied to investigate structural evolution and phase identification for a wide range of materials, offering new insights into the fundamental understanding of water and other complex systems.


Subject(s)
Ice , Molecular Dynamics Simulation , Machine Learning , Phase Transition
12.
Int J Clin Pharmacol Ther ; 62(10): 486-496, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39078055

ABSTRACT

OBJECTIVE: This study aimed to analyze the pharmacokinetic (PK) characteristics, safety, and bioequivalence (BE) of a test (T) preparation of a nifedipine controlled-release tablet and the reference (R) drug (Adalat GTIS) in Chinese study participants in the context of fasting and postprandial states. MATERIALS AND METHODS: An open-label, single-center, randomized, single-dose, two-period study was designed including two separate arms, one with administration under fasting conditions and one with administration under postprandial conditions (high-fat, high-calorie breakfast). After oral administration, the nifedipine concentrations in plasma were quantitatively analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) at regular intervals. Primary PK parameters, including the area under the concentration curve from 0 to infinity (AUC0-∞), the area under the concentration profile from 0 to the last measurable concentration time (AUC0-t), and maximal measured plasma concentration (Cmax) were log-transformed with BE limits of 80 - 125% to evaluate BE. All adverse events (AEs) were wholly supervised. RESULTS: The PK profiles of the T and R formulations were comparable to each other under both fasting and postprandial conditions. The 90% confidence intervals (CIs) of the AUC0-∞, AUC0-t, and Cmax were 92.69 - 106.06%, 93.32 - 107.05%, and 99.53 - 116.71%, respectively, under the fasting state. The 90% CIs of the AUC0-∞, AUC0-t, and Cmax were 105.05 - 117.40%, 105.43 - 117.82%, and 102.66 - 116.30%, respectively, in the postprandial arm. 47 cases of drug-associated AEs were noted in the entire research. CONCLUSION: Under both the fasting and postprandial states, the two nifedipine controlled-release formulations were bioequivalent and safe in healthy Chinese subjects.


Subject(s)
Calcium Channel Blockers , Delayed-Action Preparations , Nifedipine , Postprandial Period , Adult , Female , Humans , Male , Young Adult , Administration, Oral , Area Under Curve , Asian People , Calcium Channel Blockers/blood , Calcium Channel Blockers/pharmacokinetics , China , Chromatography, Liquid , Fasting , Food-Drug Interactions , Healthy Volunteers , Nifedipine/blood , Nifedipine/pharmacokinetics , Tablets , Tandem Mass Spectrometry , Therapeutic Equivalency
13.
Langenbecks Arch Surg ; 409(1): 169, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38822914

ABSTRACT

INTRODUCTION: Tracheoesophageal fistula (TEF) especially malignant TEF (mTEF) is an uncommon yet critical medical condition necessitating immediate intervention. This life-threatening condition frequently manifests in critically ill patients who are dependent on prolonged mechanical ventilation and are unsuitable candidates for thoracotomy due to their compromised health status. The Management of these mTEF patients remain a significant challenge.This study aimed to evaluate the safety and efficacy of using a cardiac septal occluder for the closure of mTEF. METHODS: 8 patients with mTEF underwent closure surgery using atrial/ventricular septal defect (ASD/VSD) septal occluders at the Respiratory Department of HuBei Yichang Central People's Hospital from 2021 to 2023. The procedure involved percutaneous placement of the occluder through the fistula to achieve closure. RESULTS: The placement of the cardiac septal occluder was successfully achieved with ease and efficiency in all patients. The study demonstrated that the use of cardiac septal occluder therapy in patients with mTEF can alleviate symptoms, improve quality of life, and enhance survival rates, with no significant complications observed. Furthermore, the study provided comprehensive details on surgical indications, preoperative evaluation and diagnosis, selection of occluder, methods of occlusion, and postoperative care. CONCLUSIONS: The application of cardiac septal occluder in the treatment of mTEF is a safe and effective palliative treatment. This approach may be particularly beneficial for patients with a high risk of complications and mortality associated with traditional surgical interventions.


Subject(s)
Palliative Care , Septal Occluder Device , Tracheoesophageal Fistula , Adult , Aged , Female , Humans , Male , Middle Aged , Minimally Invasive Surgical Procedures/methods , Palliative Care/methods , Quality of Life , Retrospective Studies , Tracheoesophageal Fistula/surgery , Tracheoesophageal Fistula/etiology , Treatment Outcome
14.
BMC Nephrol ; 25(1): 121, 2024 Apr 04.
Article in English | MEDLINE | ID: mdl-38575883

ABSTRACT

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.


Subject(s)
Kidney Failure, Chronic , Renal Insufficiency, Chronic , Humans , Kidney , Prognosis , Glomerular Filtration Rate , Fibrosis , Hemoglobins , Predictive Value of Tests
15.
J Ultrasound Med ; 43(2): 293-303, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37876335

ABSTRACT

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.


Subject(s)
Breast Neoplasms , Lymphadenopathy , Sentinel Lymph Node , Humans , Female , Sentinel Lymph Node/diagnostic imaging , Sentinel Lymph Node/pathology , Breast Neoplasms/pathology , Sentinel Lymph Node Biopsy , Lymph Nodes/diagnostic imaging , Lymph Nodes/pathology , Lymphatic Metastasis/diagnostic imaging , Lymphatic Metastasis/pathology , Lymphadenopathy/pathology , Axilla/pathology
16.
BMC Musculoskelet Disord ; 25(1): 122, 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38336637

ABSTRACT

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.


Subject(s)
Biological Phenomena , Exosomes , Mesenchymal Stem Cells , MicroRNAs , RNA, Long Noncoding , Humans , Apoptosis/genetics , Cell Proliferation/genetics , Exosomes/genetics , Exosomes/metabolism , Kruppel-Like Transcription Factors/genetics , Kruppel-Like Transcription Factors/metabolism , Mesenchymal Stem Cells/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Osteoblasts/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism
17.
Biochem Genet ; 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38526708

ABSTRACT

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.

18.
Arch Gynecol Obstet ; 2024 Oct 21.
Article in English | MEDLINE | ID: mdl-39433644

ABSTRACT

OBJECTIVE: Analyze the ultrasound findings, single-nucleotide polymorphism array (SNP-array) results, and pregnancy outcomes of fetuses with 17q12 deletions and duplications in the second and third trimesters. Explore the prenatal ultrasound characteristics and pregnancy outcomes of these fetuses. METHODS: Retrospective data were collected for 16 fetuses diagnosed with 17q12 deletion and seven fetuses with 17q12 duplication through SNP-array during prenatal diagnosis at a single Chinese tertiary medical center from January 2017 to December 2023. Maternal demographics, ultrasound findings of the fetuses, SNP-array results, pregnancy outcomes, and follow-up information were reviewed and analyzed. Peripheral blood from the parents was extracted to determine whether the CNVs in the fetuses were inherited or de novo. RESULTS: The copy-number variation (CNV) sizes ranged from 1.39 to 1.94 Mb in cases of 17q12 deletion and from 1.42 to 1.91 Mb in cases of 17q12 duplication. These CNVs included 15 OMIM genes, such as HNF1B, LHX1, and ACACA. In fetuses with a 17q12 deletion, the primary manifestation was renal abnormalities (93.8%, 15/16). Of these, 13 cases (81.3%, 13/16) exhibited bilateral or unilateral hyperechogenic kidneys, and 12 cases (75%, 12/16) had multicystic hyperechogenic kidneys. Two cases (12.5%, 2/16) showed multiple organ structural abnormalities. In fetuses with a 17q12 duplication, four cases (57.1%, 4/7) revealed cardiovascular system abnormalities, including tetralogy of fallot, pulmonary artery stenosis, ventricular septal defect, and tricuspid regurgitation. Two cases (28.6%, 2/7) presented with upper gastrointestinal obstruction. Additionally, one case was particularly unique, characterized by multiple structural malformations, such as ventricular septal defect, microcephaly, cleft lip, and palate. Nine cases opted for pregnancy termination, and 14 chose to continue the pregnancy. Two cases underwent surgical treatment after birth for upper gastrointestinal obstruction, and the prognosis was good. Among the 10 cases of 17q12 deletion, six cases showed consistent prenatal ultrasound findings and postnatal clinical features. Four cases were found to have discrepancies with prenatal ultrasound findings; while the renal ultrasound phenotype appeared normal during the last follow-up, two of these cases were subsequently diagnosed with neuropsychiatric phenotypes. CONCLUSION: Our study expanded the clinical phenotype spectrum of fetuses with 17q12 deletion and duplication, and conducted a preliminary evaluation of prenatal ultrasound findings and postnatal clinical phenotypes in follow-up cases. We further demonstrated a high correlation between fetuses with 17q12 deletion and hyperechogenic, multicystic kidneys. The primary manifestations in fetuses with 17q12 duplication are likely cardiovascular system malformations, which also exhibit a broad spectrum of phenotypic features.

19.
Nano Lett ; 23(11): 4983-4990, 2023 Jun 14.
Article in English | MEDLINE | ID: mdl-37212654

ABSTRACT

To achieve better properties of van der Waals (vdW) devices, vdW heterointerfaces with substrates such as hexagonal boron nitride (h-BN) were introduced to alleviate adverse substrate effects. However, the premature dielectric breakdown and its scale limitation make wider application of h-BN substrates challenging. Here we report a fluoride-based substrate that substantially improves optoelectronic and transport properties of dichalcogenide devices, with enhancement factors comparable to those of h-BN. A model system of wafer-scale fluoride calcium (CaF2) ultrathin films with the preferable growth direction along [111] is prepared by the magnetron sputtering method. Results show that the constructed SnS2/CaF2 and WS2/CaF2 devices exhibit 1 order of magnitude higher than devices based on the SiO2 substrate in electronic mobility and photoresponsivity. Theoretical calculations reveal that devices based on fluoride substrates are immune from the Coulomb impurity scattering by forming quasi-vdW interfaces, exhibiting great potential for high responsivity and mobility of photogenerated carriers in 2D vdW devices.

20.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(4): 480-485, 2024 Apr 10.
Article in Zh | MEDLINE | ID: mdl-38565516

ABSTRACT

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.


Subject(s)
Abnormalities, Multiple , Intellectual Disability , Megalencephaly , Microcephaly , Child , Humans , Microcephaly/genetics , Retrospective Studies , Chromosome Deletion , Phenotype , Molecular Biology , Intellectual Disability/genetics , DNA Helicases/genetics , DNA-Binding Proteins/genetics , Chromosomes, Human, Pair 1
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