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1.
Hum Mol Genet ; 33(10): 884-893, 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38340456

RESUMEN

Patent ductus arteriosus (PDA) is a common form of congenital heart disease. The MYH6 gene has important effects on cardiovascular growth and development, but the effect of variants in the MYH6 gene promoter on ductus arteriosus is unknown. DNA was extracted from blood samples of 721 subjects (428 patients with isolated and sporadic PDA and 293 healthy controls) and analyzed by sequencing for MYH6 gene promoter region variants. Cellular function experiments with three cell lines (HEK-293, HL-1, and H9C2 cells) and bioinformatics analyses were performed to verify their effects on gene expression. In the MYH6 gene promoter, 11 variants were identified. Four variants were found only in patients with PDA and 2 of them (g.3434G>C and g.4524C>T) were novel. Electrophoretic mobility shift assay showed that the transcription factors bound by the promoter variants were significantly altered in comparison to the wild-type in all three cell lines. Dual luciferase reporter showed that all the 4 variants reduced the transcriptional activity of the MYH6 gene promoter (P < 0.05). Prediction of transcription factors bound by the variants indicated that these variants alter the transcription factor binding sites. These pathological alterations most likely affect the contraction of the smooth muscle of ductus arteriosus, leading to PDA. This study is the first to focus on variants at the promoter region of the MYH6 gene in PDA patients with cellular function tests. Therefore, this study provides new insights to understand the genetic basis and facilitates further studies on the mechanism of PDA formation.


Asunto(s)
Miosinas Cardíacas , Conducto Arterioso Permeable , Cadenas Pesadas de Miosina , Regiones Promotoras Genéticas , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Miosinas Cardíacas/genética , Estudios de Casos y Controles , Línea Celular , Conducto Arterioso Permeable/genética , Conducto Arterioso Permeable/patología , Células HEK293 , Cadenas Pesadas de Miosina/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
2.
Proc Natl Acad Sci U S A ; 119(36): e2205629119, 2022 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-36037365

RESUMEN

Elimination of autoreactive developing B cells is an important mechanism to prevent autoantibody production. However, how B cell receptor (BCR) signaling triggers apoptosis of immature B cells remains poorly understood. We show that BCR stimulation up-regulates the expression of the lysosomal-associated transmembrane protein 5 (LAPTM5), which in turn triggers apoptosis of immature B cells through two pathways. LAPTM5 causes BCR internalization, resulting in decreased phosphorylation of SYK and ERK. In addition, LAPTM5 targets the E3 ubiquitin ligase WWP2 for lysosomal degradation, resulting in the accumulation of its substrate PTEN. Elevated PTEN levels suppress AKT phosphorylation, leading to increased FOXO1 expression and up-regulation of the cell cycle inhibitor p27Kip1 and the proapoptotic molecule BIM. In vivo, LAPTM5 is involved in the elimination of autoreactive B cells and its deficiency exacerbates autoantibody production. Our results reveal a previously unidentified mechanism that contributes to immature B cell apoptosis and B cell tolerance.


Asunto(s)
Apoptosis , Tolerancia Inmunológica , Proteínas de la Membrana , Células Precursoras de Linfocitos B , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Proteína Forkhead Box O1/metabolismo , Humanos , Lisosomas/metabolismo , Proteínas de la Membrana/genética , Fosfohidrolasa PTEN/metabolismo , Células Precursoras de Linfocitos B/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo
3.
EMBO J ; 39(15): e102931, 2020 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-32511795

RESUMEN

Sterile alpha motif and histidine-aspartic acid domain-containing protein 1 (SAMHD1), a dNTP triphosphohydrolase, regulates the levels of cellular dNTPs through their hydrolysis. SAMHD1 protects cells from invading viruses that depend on dNTPs to replicate and is frequently mutated in cancers and Aicardi-Goutières syndrome, a hereditary autoimmune encephalopathy. We discovered that SAMHD1 localizes at the immunoglobulin (Ig) switch region, and serves as a novel DNA repair regulator of Ig class switch recombination (CSR). Depletion of SAMHD1 impaired not only CSR but also IgH/c-Myc translocation. Consistently, we could inhibit these two processes by elevating the cellular nucleotide pool. A high frequency of nucleotide insertion at the break-point junctions is a notable feature in SAMHD1 deficiency during activation-induced cytidine deaminase-mediated genomic instability. Interestingly, CSR induced by staggered but not blunt, double-stranded DNA breaks was impaired by SAMHD1 depletion, which was accompanied by enhanced nucleotide insertions at recombination junctions. We propose that SAMHD1-mediated dNTP balance regulates dNTP-sensitive DNA end-processing enzyme and promotes CSR and aberrant genomic rearrangements by suppressing the insertional DNA repair pathway.


Asunto(s)
Reparación del ADN , Desoxirribonucleótidos/metabolismo , Cambio de Clase de Inmunoglobulina , Proteína 1 que Contiene Dominios SAM y HD/metabolismo , Línea Celular , Desoxirribonucleótidos/genética , Humanos , Proteína 1 que Contiene Dominios SAM y HD/genética
4.
Funct Integr Genomics ; 24(3): 103, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38913281

RESUMEN

Breast cancer severely affects women health. 70% of breast cancer are estrogen receptor positive. Breast cancer stem cells are a group of tumor with plasticity, causing tumor relapse and metastasis. RUNX3 is a tumor suppressor frequently inactivated in estrogen receptor positive breast cancer. However, the mechanism of how RUNX3 is involved in the regualation of cancer stem cell traits in estrogen receptor positive breast cancer remains elusive. In this study, we utilized cut-tag assay to investigate the binding profile RUNX3 in BT474 and T47D cell, and confirmed EXOSC4 as the bona-fide target of RUNX3; RUNX3 could bind to the promoter are of EXOSC4 to suppress its expression. Furthermore, EXOSC4 could increase the colony formation, cell invasion and mammosphere formation ability of breast cancer cells and upregulate the the expression of SOX2 and ALDH1. Consistent with these findings, EXOSC4 was associated with poorer survival for Luminal B/Her2 breast cancer patiens. At last, we confirmed that EXOSC4 mediated the tumor suppressive role of RUNX3 in breast cancer cells. In conclusion, we demonstrate that RUNX3 directly binds to the promoter region of EXOSC4, leading to the suppression of EXOSC4 expression and exerting a tumor-suppressive effect in estrogen receptor postivive breast cancer cells.


Asunto(s)
Neoplasias de la Mama , Subunidad alfa 3 del Factor de Unión al Sitio Principal , Regiones Promotoras Genéticas , Subunidad alfa 3 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 3 del Factor de Unión al Sitio Principal/metabolismo , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Femenino , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Familia de Aldehído Deshidrogenasa 1/metabolismo , Familia de Aldehído Deshidrogenasa 1/genética , Factores de Transcripción SOXB1/metabolismo , Factores de Transcripción SOXB1/genética , Retinal-Deshidrogenasa/metabolismo , Retinal-Deshidrogenasa/genética , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología
5.
J Clin Immunol ; 44(6): 131, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775840

RESUMEN

RHOH, an atypical small GTPase predominantly expressed in hematopoietic cells, plays a vital role in immune function. A deficiency in RHOH has been linked to epidermodysplasia verruciformis, lung disease, Burkitt lymphoma and T cell defects. Here, we report a novel germline homozygous RHOH c.245G > A (p.Cys82Tyr) variant in a 21-year-old male suffering from recurrent, invasive, opportunistic infections affecting the lungs, eyes, and brain. His sister also succumbed to a lung infection during early adulthood. The patient exhibited a persistent decrease in CD4+ T, B, and NK cell counts, and hypoimmunoglobulinemia. The patient's T cell showed impaired activation upon in vitro TCR stimulation. In Jurkat T cells transduced with RHOHC82Y, a similar reduction in activation marker CD69 up-regulation was observed. Furthermore, the C82Y variant showed reduced RHOH protein expression and impaired interaction with the TCR signaling molecule ZAP70. Together, these data suggest that the newly identified autosomal-recessive RHOH variant is associated with T cell dysfunction and recurrent opportunistic infections, functioning as a hypomorph by disrupting ZAP70-mediated TCR signaling.


Asunto(s)
Homocigoto , Infecciones Oportunistas , Humanos , Masculino , Adulto Joven , Células Jurkat , Activación de Linfocitos/genética , Infecciones Oportunistas/genética , Infecciones Oportunistas/inmunología , Linaje , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Recurrencia , Linfocitos T/inmunología , Proteína Tirosina Quinasa ZAP-70/genética , Proteína Tirosina Quinasa ZAP-70/metabolismo
6.
Nat Mater ; 22(4): 489-494, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36959503

RESUMEN

Pressure-induced magnetic phase transitions are attracting interest as a means to detect superconducting behaviour at high pressures in diamond anvil cells, but determining the local magnetic properties of samples is a challenge due to the small volumes of sample chambers. Optically detected magnetic resonance of nitrogen vacancy centres in diamond has recently been used for the in situ detection of pressure-induced phase transitions. However, owing to their four orientation axes and temperature-dependent zero-field splitting, interpreting these optically detected magnetic resonance spectra remains challenging. Here we study the optical and spin properties of implanted silicon vacancy defects in 4H-silicon carbide that exhibit single-axis and temperature-independent zero-field splitting. Using this technique, we observe the magnetic phase transition of Nd2Fe14B at about 7 GPa and map the critical temperature-pressure phase diagram of the superconductor YBa2Cu3O6.6. These results highlight the potential of silicon vacancy-based quantum sensors for in situ magnetic detection at high pressures.

7.
Magn Reson Med ; 91(4): 1512-1527, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38098305

RESUMEN

PURPOSE: Guanidinium CEST is sensitive to metabolic changes and pH variation in ischemia, and it can offer advantages over conventional pH-sensitive amide proton transfer (APT) imaging by providing hyperintense contrast in stroke lesions. However, quantifying guanidinium CEST is challenging due to multiple overlapping components and a close frequency offset from water. This study aims to evaluate the applicability of a new rapid and model-free CEST quantification method using double saturation power, termed DSP-CEST, for isolating the guanidinium CEST effect from confounding factors in ischemia. To further reduce acquisition time, the DSP-CEST was combined with a quasi-steady state (QUASS) CEST technique to process non-steady-state CEST signals. METHODS: The specificity and accuracy of the DSP-CEST method in quantifying the guanidinium CEST effect were assessed by comparing simulated CEST signals with/without the contribution from confounding factors. The feasibility of this method for quantifying guanidinium CEST was evaluated in a rat model of global ischemia induced by cardiac arrest and compared to a conventional multiple-pool Lorentzian fit method. RESULTS: The DSP-CEST method was successful in removing all confounding components and quantifying the guanidinium CEST signal increase in ischemia. This suggests that the DSP-CEST has the potential to provide hyperintense contrast in stroke lesions. Additionally, the DSP-CEST was shown to be a rapid method that does not require the acquisition of the entire or a portion of the CEST Z-spectrum that is required in conventional model-based fitting approaches. CONCLUSION: This study highlights the potential of DSP-CEST as a valuable tool for rapid and specific detection of viable tissues.


Asunto(s)
Encéfalo , Accidente Cerebrovascular , Ratas , Animales , Encéfalo/metabolismo , Imagen por Resonancia Magnética/métodos , Guanidina/metabolismo , Roedores , Isquemia/diagnóstico por imagen , Isquemia/metabolismo , Amidas/metabolismo
8.
Magn Reson Med ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38767321

RESUMEN

PURPOSE: To improve the spatial resolution and repeatability of a non-contrast MRI technique for simultaneous time resolved 3D angiography and perfusion imaging by developing an efficient 3D cone trajectory design. METHODS: A novel parameterized 3D cone trajectory design incorporating the 3D golden angle was integrated into 4D combined angiography and perfusion using radial imaging and arterial spin labeling (CAPRIA) to achieve higher spatial resolution and sampling efficiency for both dynamic angiography and perfusion imaging with flexible spatiotemporal resolution. Numerical simulations and physical phantom scanning were used to optimize the cone design. Eight healthy volunteers were scanned to compare the original radial trajectory in 4D CAPRIA with our newly designed cone trajectory. A locally low rank reconstruction method was used to leverage the complementary k-space sampling across time. RESULTS: The improved sampling in the periphery of k-space obtained with the optimized 3D cone trajectory resulted in improved spatial resolution compared with the radial trajectory in phantom scans. Improved vessel sharpness and perfusion visualization were also achieved in vivo. Less dephasing was observed in the angiograms because of the short TE of our cone trajectory and the improved k-space sampling efficiency also resulted in higher repeatability compared to the original radial approach. CONCLUSION: The proposed 3D cone trajectory combined with 3D golden angle ordering resulted in improved spatial resolution and image quality for both angiography and perfusion imaging and could potentially benefit other applications that require an efficient sampling scheme with flexible spatial and temporal resolution.

9.
Ann Surg Oncol ; 31(2): 838-846, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37919448

RESUMEN

BACKGROUND: This study updated 3-year analyses to further characterize the impact of docetaxel, cisplatin, and fluorouracil (TPF) chemotherapy followed by surgery. METHODS: This study was a single-center phase 2 clinical trial. Patients with a diagnosis of borderline resectable esophageal squamous cell carcinoma (BR-ESCC) because of the primary tumor or bulky lymph node that potentially invaded adjacent organs were eligible. The treatment started with TPF chemotherapy followed by surgery if the cancer was resectable, or by concurrent chemoradiation if it was unresectable. This updated report presents the 3-year overall survival (OS) and progression-free survival (PFS) rates. RESULTS: Surgery was performed for 27 patients (57.4%), and R0 resection was confirmed in 25 patients (53.2%). Pathologic complete response was confirmed in four patients (8.5%). The median follow-up time for the surviving patients was 44.8 months (range, 3.4-74.6 months). The median OS for all the patients was 41.9 months (95% confidence interval [CI], 18.6-65.3 months), with a median PFS of 38.7 months (95% CI, 23.5-53.9 months). The 3-year survival rate for all the patients was 54.4%. The 3-year survival rate for the R0 patients was 65.4%. CONCLUSION: Long-term follow-up evaluation confirmed that TPF followed by surgery is feasible and promising in terms of survival for BR-ESCC patients. Trial Registration ClinicalTrials.gov identifer: NCT02976909.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Cisplatino , Neoplasias Esofágicas/tratamiento farmacológico , Quimioterapia de Inducción , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/patología , Taxoides , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Paclitaxel , Fluorouracilo
10.
J Nutr ; 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38763264

RESUMEN

BACKGROUND: Laying hens undergo intensive metabolism and are vulnerable to cardiac insults. Previous research demonstrated overt heart disorders of broiler chickens induced by dietary Se deficiency. OBJECTIVES: This study aimed to reveal effects and mechanism of dietary Se insufficiency on cardiac injuries of egg-type chicks in their early life. METHODS: White Leghorn chicks (0-d-old, female) were fed a corn-soy, Se-insufficient basal diet (BD, 0.05 mg Se/kg; n = 11) or the BD supplemented with 0.3 mg Se/kg (as sodium selenite; n = 8) for 35 d. Cardiac tissues were collected at the end of study for histology and to determine its relationship with heart Se contents, selenoprotein expression profiles, antioxidant and inflammatory status, and the Toll-like receptor 4/extracellular signal-regulated kinases/p38 map kinase/c-Jun N-terminal kinase (TLR4/ERK/P38/JNK) pathway. RESULTS: Compared with those fed 0.35 mg Se/kg, chicks fed BD had significantly lower body weights and average daily gain, and 28% lower heart Se, and developed cardiac mononuclear inflammatory cell infiltration, along with elevated (P < 0.05) serum concentrations of creatine kinase, aldolase, and interleukin-1 (IL-1). The BD decreased (P < 0.05) body weight and heart glutathione contents and expression of selenoproteins but increased (P < 0.05) heart concentrations of malondialdehyde and reactive oxygen species. These changes were associated with increased (P < 0.05) mRNA and/or protein concentrations of cyclooxygenases, lipoxygenase-12, cytokines (IL-1ß), nuclear factor (NF) κB subunit, chemokines, and receptors (CCL20, CXCR1, and CXCLI2) and increased (P < 0.1) TLR4/ERK /P38/JNK in the heart of Se-insufficient chicks. CONCLUSIONS: Dietary Se insufficiency induces infiltration of mononuclear inflammatory cells in the heart of egg-type chicks. This cardiac injury was mediated by decreased functional expressions of selenoproteins, which resulted in apparent elevated oxidative stress and subsequent activations of the TLR4 pathway and NF κB.

11.
J Magn Reson Imaging ; 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38236785

RESUMEN

BACKGROUND: Quantitative in-situ pH mapping of gliomas is important for therapeutic interventions, given its significant association with tumor progression, invasion, and metastasis. Although chemical exchange saturation transfer (CEST) offers a noninvasive way for pH imaging based on the pH-dependent exchange rate (ksw ), the reliable quantification of ksw in glioma remains constrained due to technical challenges. PURPOSE: To quantify the pH of gliomas by measuring the proton exchange rate through optimized omega plot analysis. STUDY TYPE: Prospective. PHANTOMS/ANIMAL MODEL/SUBJECTS: Creatine and murine brain lysates phantoms, six rats with glioma xenograft model, and three patients with World Health Organization grade 2-4 gliomas. FIELD STRENGTH/SEQUENCE: 11.7 T, 7.0 T, CEST imaging, T2 -weighted (T2 W) imaging, and T1 -mapping. ASSESSMENT: Omega plot analysis, quasi-steady-state (QUASS) analysis, multi-pool Lorentzian fitting, amine and amide concentration-independent detection, pH enhanced method with the combination of amide and guanidyl (pHenh ), and magnetization transfer ratio (MTR) were utilized for pH metric quantification. The clinical outcomes were determined through radiologic follow-up and histopathological analysis. STATISTICAL TESTS: Mann-Whitney U test was performed to compare glioma with normal tissue, and Pearson's correlation analysis was used to assess the relationship between ksw and other parameters. RESULTS: In vitro experiments reveal that the determined ksw at 2 ppm increases exponentially with pH (creatine phantoms: ksw = 106 + 0.147 × 10(pH-4.198) ; lysates: ksw = 185.1 + 0.101 × 10(pH-3.914) ). Omega plot analysis exhibits a linear correlation between 1/MTRRex and 1/ω1 2 in the glioma xenografts (R2 > 0.98) and glioma patients (R2 > 0.99). The exchange rate in the rat glioma decreases compared to the contralateral normal tissue (349.46 ± 30.40 s-1 vs. 403.54 ± 51.01 s-1 , P = 0.025), while keeping independence from changes in concentration (r = 0.5037, P = 0.095). Similar pattern was observed in human data. DATA CONCLUSION: Utilizing QUASS-based, spillover-, and MT-corrected omega plot analysis for the measurement of exchange rates, offers a feasible method for quantifying pH within glioma. LEVEL OF EVIDENCE: NA TECHNICAL EFFICACY: Stage 1.

12.
Cell Commun Signal ; 22(1): 164, 2024 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448900

RESUMEN

Pancreatic neuroendocrine tumors (PanNETs), though uncommon, have a high likelihood of spreading to other body parts. Previously, the genetic diversity and evolutionary patterns in metastatic PanNETs were not well understood. To investigate this, we performed multiregion sampling whole-exome sequencing (MRS-WES) on samples from 10 patients who had not received prior treatment for metastatic PanNETs. This included 29 primary tumor samples, 31 lymph node metastases, and 15 liver metastases. We used the MSK-MET dataset for survival analysis and validation of our findings. Our research indicates that mutations in the MEN1/DAXX genes might trigger the early stages of PanNET development. We categorized the patients based on the presence (MEN1/DAXXmut, n = 7) or absence (MEN1/DAXXwild, n = 3) of these mutations. Notable differences were observed between the two groups in terms of genetic alterations and clinically relevant mutations, confirmed using the MSK-MET dataset. Notably, patients with mutations in MEN1/DAXX/ATRX genes had a significantly longer median overall survival compared to those without these mutations (median not reached vs. 43.63 months, p = 0.047). Multiplex immunohistochemistry (mIHC) analysis showed a more prominent immunosuppressive environment in metastatic tumors, especially in patients with MEN1/DAXX mutations. These findings imply that MEN1/DAXX mutations lead PanNETs through a unique evolutionary path. The disease's progression pattern indicates that PanNETs can spread early, even before clinical detection, highlighting the importance of identifying biomarkers related to metastasis to guide personalized treatment strategies.


Asunto(s)
Neoplasias Hepáticas , Tumores Neuroendocrinos , Neoplasias Pancreáticas , Humanos , Secuenciación del Exoma , Tumores Neuroendocrinos/genética , Genómica , Neoplasias Hepáticas/genética , Neoplasias Pancreáticas/genética , Microambiente Tumoral
13.
BMC Anesthesiol ; 24(1): 121, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38539078

RESUMEN

INTRODUCTION: Postoperative nausea and vomiting (PONV) is one of the most common adverse events following orthognathic surgery. It's a distressing feeling for patients and continues to be the cause of postoperative complications such as bleeding, delayed healing, and wound infection. This scoping review aims to identify effective PONV prophylaxis strategies during orthognathic surgery that have emerged in the past 15 years. METHODS: We searched Pubmed, Cochrane Controlled Register of Trials, and Embase from 2008 to May 2023. Studies meeting the following criteria were eligible for inclusion: (1) recruited patients undergo any orthognathic surgery; (2) evaluated any pharmacologic or non-pharmacologic method to prevent PONV. Studies meeting the following criteria were excluded: (1) case series, review papers, or retrospective studies; (2) did not report our prespecified outcomes. RESULTS: Twenty-one studies were included in this review. Pharmacological methods for PONV prevention include ondansetron and dexamethasone (3 studies), peripheral nerve block technique (4 studies), dexmedetomidine (1 study), pregabalin (2 studies), nefopam (2 studies), remifentanil (1 study), propofol (2 studies), and penehyclidine (1 study). Non-pharmacologic methods include capsicum plaster (1 study), throat packs (2 studies) and gastric aspiration (2 studies). CONCLUSIONS: Based on current evidence, we conclude that prophylactic antiemetics like dexamethasone, ondansetron, and penehyclidine are the first defense against PONV. Multimodal analgesia with nerve block techniques and non-opioid analgesics should be considered due to their notable opioid-sparing and PONV preventive effect. For the non-pharmacological methods, throat packs are not recommended for routine use because of their poor effect and serious complications. More prospective RCTs are required to confirm whether gastric aspiration can prevent PONV effectively for patients undergoing orthognathic surgery.


Asunto(s)
Antieméticos , Cirugía Ortognática , Humanos , Náusea y Vómito Posoperatorios/prevención & control , Náusea y Vómito Posoperatorios/tratamiento farmacológico , Ondansetrón/uso terapéutico , Estudios Prospectivos , Estudios Retrospectivos , Antieméticos/uso terapéutico , Dexametasona/uso terapéutico
14.
Skeletal Radiol ; 53(5): 881-890, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37935923

RESUMEN

PURPOSE: To investigate the feasibility and application of a novel imaging technique, a three-dimensional dual adiabatic inversion recovery prepared ultrashort echo time (3D DIR-UTE) sequence, for high contrast assessment of cartilaginous endplate (CEP) imaging with head-to-head comparisons between other UTE imaging techniques. METHOD: The DIR-UTE sequence employs two narrow-band adiabatic full passage (AFP) pulses to suppress signals from long T2 water (e.g., nucleus pulposus (NP)) and bone marrow fat (BMF) independently, followed by multispoke UTE acquisition to detect signals from the CEP with short T2 relaxation times. The DIR-UTE sequence, in addition to three other UTE sequences namely, an IR-prepared and fat-saturated UTE (IR-FS-UTE), a T1-weighted and fat-saturated UTE sequence (T1w-FS-UTE), and a fat-saturated UTE (FS-UTE) was used for MR imaging on a 3 T scanner to image six asymptomatic volunteers, six patients with low back pain, as well as a human cadaveric specimen. The contrast-to-noise ratio of the CEP relative to the adjacent structures-specifically the NP and BMF-was then compared from the acquired images across the different UTE sequences. RESULTS: For asymptomatic volunteers, the DIR-UTE sequence showed significantly higher contrast-to-noise ratio values between the CEP and BMF (CNRCEP-BMF) (19.9 ± 3.0) and between the CEP and NP (CNRCEP-NP) (23.1 ± 1.7) compared to IR-FS-UTE (CNRCEP-BMF: 17.3 ± 1.2 and CNRCEP-NP: 19.1 ± 1.8), T1w-FS-UTE (CNRCEP-BMF: 9.0 ± 2.7 and CNRCEP-NP: 10.4 ± 3.5), and FS-UTE (CNRCEP-BMF: 7.7 ± 2.2 and CNRCEP-NP: 5.8 ± 2.4) for asymptomatic volunteers (all P-values < 0.001). For the spine sample and patients with low back pain, the DIR-UTE technique detected abnormalities such as irregularities and focal defects in the CEP regions. CONCLUSION: The 3D DIR-UTE sequence is able to provide high-contrast volumetric CEP imaging for human spines on a clinical 3 T scanner.


Asunto(s)
Dolor de la Región Lumbar , Humanos , Huesos , Imagen por Resonancia Magnética/métodos , Cartílago , Fantasmas de Imagen , Imagenología Tridimensional/métodos
15.
Mikrochim Acta ; 191(5): 254, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38594554

RESUMEN

A fluorescent multichannel sensor array has been established based on three carbon dots derived from Tibetan medicine waste for rapid quantification and discrimination of six heavy metal ions. Due to the chelation between metal ions and carbon dots (CDs), this fluorescence "turn off" mode sensing array can quantify six metal ions as low as "µM" level. Moreover, the six heavy metal ions display varying quenching effects on these three CDs owing to diverse chelating abilities between each other, producing differential fluorescent signals for three sensing channels, which can be plotted as specific fingerprints and converted into intuitive identification profiles via principal component analysis (PCA) and hierarchical cluster analysis (HCA) technologies to accurately distinguish Cu2+, Fe3+, Mn2+, Ag+, Ce4+, and Ni2+ with the minimum differentiated concentration of 5 µM. Valuably, this sensing array unveils good sensitivity, exceptional selectivity, ideal stability, and excellent anti-interference ability for both mixed standards and actual samples. Our contribution provides a novel approach for simultaneous determination of multiple heavy metal ions in environmental samples, and it will inspire the development of other advanced optical sensing array for simultaneous quantification and discrimination of multiple targets.

16.
Sensors (Basel) ; 24(8)2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38676169

RESUMEN

Accurate and reliable pose estimation of boom-type roadheaders is the key to the forming quality of the tunneling face in coal mines, which is of great importance to improve tunneling efficiency and ensure the safety of coal mine production. The multi-laser-beam target-based visual localization method is an effective way to realize accurate and reliable pose estimation of a roadheader body. However, the complex background interference in coal mines brings great challenges to the stable and accurate segmentation and extraction of laser beam features, which has become the main problem faced by the long-distance visual positioning method of underground equipment. In this paper, a semantic segmentation network for underground laser beams in coal mines, RCEAU-Net, is proposed based on U-Net. The network introduces residual connections in the convolution of the encoder and decoder parts, which effectively fuses the underlying feature information and improves the gradient circulation performance of the network. At the same time, by introducing cascade multi-scale convolution in the skipping connection section, which compensates for the lack of contextual semantic information in U-Net and improves the segmentation effect of the network model on tiny laser beams at long distance. Finally, the introduction of an efficient multi-scale attention module with cross-spatial learning in the encoder enhances the feature extraction capability of the network. Furthermore, the laser beam target dataset (LBTD) is constructed based on laser beam target images collected from several coal mines, and the proposed RCEAU-Net model is then tested and verified. The experimental results show that, compared with the original U-Net, RCEAU-Net can ensure the real-time performance of laser beam segmentation while increasing the Accuracy by 0.19%, Precision by 2.53%, Recall by 22.01%, and Intersection and Union Ratio by 8.48%, which can meet the requirements of multi-laser-beam feature segmentation and extraction under complex backgrounds in coal mines, so as to further ensure the accuracy and stability of long-distance visual positioning for boom-type roadheaders and ensure the safe production in the working face.

17.
Nano Lett ; 23(10): 4334-4343, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37155148

RESUMEN

Optically addressable spin defects in silicon carbide (SiC) have emerged as attractable platforms for various quantum technologies. However, the low photon count rate significantly limits their applications. We strongly enhanced the brightness by 7 times and spin-control strength by 14 times of single divacancy defects in 4H-SiC membranes using a surface plasmon generated by gold film coplanar waveguides. The mechanism of the plasmonic-enhanced effect is further studied by tuning the distance between single defects and the surface of the gold film. A three-energy-level model is used to determine the corresponding transition rates consistent with the enhanced brightness of single defects. Lifetime measurements also verified the coupling between defects and surface plasmons. Our scheme is low-cost, without complicated microfabrication and delicate structures, which is applicable for other spin defects in different materials. This work would promote developing spin-defect-based quantum applications in mature SiC materials.

18.
Neuroimage ; 277: 120231, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37330025

RESUMEN

Estimating structural connectivity from diffusion-weighted magnetic resonance imaging is a challenging task, partly due to the presence of false-positive connections and the misestimation of connection weights. Building on previous efforts, the MICCAI-CDMRI Diffusion-Simulated Connectivity (DiSCo) challenge was carried out to evaluate state-of-the-art connectivity methods using novel large-scale numerical phantoms. The diffusion signal for the phantoms was obtained from Monte Carlo simulations. The results of the challenge suggest that methods selected by the 14 teams participating in the challenge can provide high correlations between estimated and ground-truth connectivity weights, in complex numerical environments. Additionally, the methods used by the participating teams were able to accurately identify the binary connectivity of the numerical dataset. However, specific false positive and false negative connections were consistently estimated across all methods. Although the challenge dataset doesn't capture the complexity of a real brain, it provided unique data with known macrostructure and microstructure ground-truth properties to facilitate the development of connectivity estimation methods.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Procesamiento de Imagen Asistido por Computador , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen de Difusión por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Método de Montecarlo , Fantasmas de Imagen
19.
N Engl J Med ; 382(18): 1708-1720, 2020 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-32109013

RESUMEN

BACKGROUND: Since December 2019, when coronavirus disease 2019 (Covid-19) emerged in Wuhan city and rapidly spread throughout China, data have been needed on the clinical characteristics of the affected patients. METHODS: We extracted data regarding 1099 patients with laboratory-confirmed Covid-19 from 552 hospitals in 30 provinces, autonomous regions, and municipalities in mainland China through January 29, 2020. The primary composite end point was admission to an intensive care unit (ICU), the use of mechanical ventilation, or death. RESULTS: The median age of the patients was 47 years; 41.9% of the patients were female. The primary composite end point occurred in 67 patients (6.1%), including 5.0% who were admitted to the ICU, 2.3% who underwent invasive mechanical ventilation, and 1.4% who died. Only 1.9% of the patients had a history of direct contact with wildlife. Among nonresidents of Wuhan, 72.3% had contact with residents of Wuhan, including 31.3% who had visited the city. The most common symptoms were fever (43.8% on admission and 88.7% during hospitalization) and cough (67.8%). Diarrhea was uncommon (3.8%). The median incubation period was 4 days (interquartile range, 2 to 7). On admission, ground-glass opacity was the most common radiologic finding on chest computed tomography (CT) (56.4%). No radiographic or CT abnormality was found in 157 of 877 patients (17.9%) with nonsevere disease and in 5 of 173 patients (2.9%) with severe disease. Lymphocytopenia was present in 83.2% of the patients on admission. CONCLUSIONS: During the first 2 months of the current outbreak, Covid-19 spread rapidly throughout China and caused varying degrees of illness. Patients often presented without fever, and many did not have abnormal radiologic findings. (Funded by the National Health Commission of China and others.).


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus , Brotes de Enfermedades , Pandemias , Neumonía Viral , Adolescente , Adulto , Anciano , COVID-19 , Niño , China/epidemiología , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/terapia , Femenino , Fiebre/etiología , Humanos , Masculino , Persona de Mediana Edad , Gravedad del Paciente , Neumonía Viral/complicaciones , Neumonía Viral/diagnóstico , Neumonía Viral/epidemiología , Neumonía Viral/terapia , SARS-CoV-2 , Adulto Joven
20.
Magn Reson Med ; 89(1): 299-307, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36089834

RESUMEN

PURPOSE: Chemical exchange saturation transfer (CEST) MRI is promising for detecting dilute metabolites and microenvironment properties, which has been increasingly adopted in imaging disorders such as acute stroke and cancer. However, in vivo CEST MRI quantification remains challenging because routine asymmetry analysis (MTRasym ) or Lorentzian decoupling measures a combined effect of the labile proton concentration and its exchange rate. Therefore, our study aimed to quantify amide proton concentration and exchange rate independently in a cardiac arrest-induced global ischemia rat model. METHODS: The amide proton CEST (APT) effect was decoupled from tissue water, macromolecular magnetization transfer, nuclear Overhauser enhancement, guanidinium, and amine protons using the image downsampling expedited adaptive least-squares (IDEAL) fitting algorithm on Z-spectra obtained under multiple RF saturation power levels, before and after global ischemia. Omega plot analysis was applied to determine amide proton concentration and exchange rate simultaneously. RESULTS: Global ischemia induces a significant APT signal drop from intact tissue. Using the modified omega plot analysis, we found that the amide proton exchange rate decreased from 29.6 ± 5.6 to 12.1 ± 1.3 s-1 (P < 0.001), whereas the amide proton concentration showed little change (0.241 ± 0.035% vs. 0.202 ± 0.034%, P = 0.074) following global ischemia. CONCLUSION: Our study determined the labile proton concentration and exchange rate underlying the in vivo APT MRI. The significant change in the exchange rate, but not the concentration of amide proton demonstrated that the pH effect dominates the APT contrast during tissue ischemia.


Asunto(s)
Imagen por Resonancia Magnética , Protones , Animales , Ratas , Imagen por Resonancia Magnética/métodos , Concentración de Iones de Hidrógeno , Amidas/metabolismo , Isquemia
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