Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 56
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-39320964

RESUMO

Terahertz absorbers play a crucial role in terahertz detectors, radar stealth, electromagnetic shielding, and other fields. However, the design and fabrication of flexible terahertz broadband absorbers remain a challenge at present. Here, we demonstrated a terahertz broadband absorber based on a copper composite film (CCF) consisting of a copper foam and an organic silica gel doped with Fe3O4 powder. The CCF can be fabricated by the infiltration method. The influence of the thickness and the pore size of the copper foam and the mass fraction of doped Fe3O4 powder on the absorption bandwidth were investigated. When the thickness of the CCF is 1.5 mm, the pore size of the copper foam is 95 pores per inch (ppi), and the mass fraction of Fe3O4 is 1%; a broadband absorption is achieved in the range of 0.11-3.5 THz. It is noted that the mass fraction of Fe3O4 has a significant impact on the absorption bandwidth. In addition, the thickness of the CCF and the pore size of the copper foam also have an impact on the absorption. The impedance matching theory is introduced to understand the mechanism of broadband absorption. This flexible broadband absorber has potential application in terahertz stealth, shielding, and the sixth-generation (6G) broadband wireless communication in the future.

2.
J Neurointerv Surg ; 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39332900

RESUMO

BACKGROUND: Previous studies have indicated that a subset of patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO) experience spontaneous recanalization (SR), but the prognosis and factors associated with SR in these individuals are not well characterized. METHODS: We conducted a post hoc secondary analysis of the Study of Endovascular Therapy in Acute Anterior Circulation Large Vessel Occlusive Patients with a Large Infarct Core (ANGEL-ASPECT) trial. SR in the medical management group was defined as a modified arterial occlusive lesion (AOL) grade of 2 or 3 on computed tomography angiography (CTA) or magnetic resonance angiography (MRA) at 36 hours (±12 hours). RESULTS: SR was detected in 67 out of 184 patients (36.4%) in the medical management (MM) group. The median age of patients was 67 years (interquartile range (IQR) 58-72), and 48 (71.6%) were male. The adjusted odds ratio (aOR) for 90-day modified Rankin Scale (mRS) score shift toward better outcomes of the MM with SR group vs the MM without SR group was 1.83, with marginally significant difference (95% confidence interval (CI) 0.992 to 3.36; P=0.053). No significant difference was found between the MM with SR group and EVT recanalization group (aOR 1.45; 95% CI 0.86 to 2.43; P=0.16) with similar findings in the inverse probability treatment weighting analysis (OR 0.85; 95% CI 0.49 to 1.48; P=0.57). Multivariable regression analysis showed that hypertension, atherothrombotic stroke and higher clot burden score were factors associated with SR. CONCLUSIONS: SR in medically managed patients with acute large ischemic stroke caused by LVO was associated with good functional outcome. An improved understanding of SR patients may be helpful to develop therapeutic strategy in patients with large infarct due to LVO in anterior circulation. TRIAL REGISTRATION NUMBER: NCT04551664.

3.
J Neurointerv Surg ; 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39209427

RESUMO

BACKGROUND: Cerebral arteriovenous malformation (AVM) is a cerebrovascular disorder posing a risk for intracranial hemorrhage. However, there are few reliable quantitative indices to predict hemorrhage risk accurately. This study aimed to identify potential biomarkers for hemorrhage risk by quantitatively analyzing the hemodynamic and morphological features within the AVM nidus. METHODS: This study included three datasets comprising consecutive patients with untreated AVMs between January 2008 to December 2023. Training and test datasets were used to train and evaluate the model. An independent validation dataset of patients receiving conservative treatment was used to evaluate the model performance in predicting subsequent hemorrhage during follow-up. Hemodynamic and morphological features were quantitatively extracted based on digital subtraction angiography (DSA). Individual models using various machine learning algorithms and an ensemble model were constructed on the training dataset. Model performance was assessed using the confusion matrix-related metrics. RESULTS: This study included 844 patients with AVMs, distributed across the training (n=597), test (n=149), and validation (n=98) datasets. Five hemodynamic and 14 morphological features were quantitatively extracted for each patient. The ensemble model, constructed based on five individual machine-learning models, achieved an area under the curve of 0.880 (0.824-0.937) on the test dataset and 0.864 (0.769-0.959) on the independent validation dataset. CONCLUSION: Quantitative hemodynamic and morphological features extracted from DSA data serve as potential indicators for assessing the rupture risk of AVM. The ensemble model effectively integrated multidimensional features, demonstrating favorable performance in predicting subsequent rupture of AVM.

4.
J Neurosurg ; : 1-10, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39126723

RESUMO

OBJECTIVE: Pipeline embolization device (PED) placement for the treatment of intracranial aneurysms is safe and effective under general anesthesia (GA). However, GA is associated with certain risks, longer procedural time, and higher hospital cost. The authors aimed to compare clinical outcomes and hospital cost between GA and local anesthesia (LA) procedures in patients who underwent PED placement for intracranial aneurysm treatment. METHODS: This retrospective study analyzed the charts of 216 patients with 223 intracranial aneurysms treated using the PED from June 2022 to March 2023. Cases were grouped according to type of anesthesia administered (LA or GA). Propensity score matching (PSM) was used to balance the groups to minimize confounding bias. RESULTS: Eighty-four patients with 88 aneurysms were treated under LA, and 132 patients with 135 aneurysms were treated under GA. The complication rate and modified Rankin Scale score at 6 months were similar in both groups. Procedural time was significantly shorter with LA both before (87.47 ± 22.68 minutes vs 118.90 ± 46.80 minutes, p < 0.001) and after (84.75 ± 16.77 minutes vs 110.02 ± 38.56 minutes, p < 0.001) PSM. LA eliminates the need for postanesthesia recovery. Hospital cost was significantly lower in the LA group both before ($30,820.74 ± $3216.93 vs $32,846.62 ± $4731.50, p = 0.001) and after ($30,127.83 ± $2763.12 vs $33,874.41 ± $3163.56, p = 0.002) PSM. CONCLUSIONS: PED placement under LA can achieve satisfactory outcomes similar to those of PED placement under GA; however, the use of LA reduces procedural time and hospital cost.

5.
Clin Neurol Neurosurg ; 245: 108515, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39178636

RESUMO

BACKGROUND: Cognard type IIa+b dural arteriovenous fistulas (DAVFs) in the lateral sinuses are often complicated with venous sinus obstruction and accompanied by clinical symptoms and a risk of hemorrhage. The purpose of this study was to assess venous sinus stenting as a viable alternative treatment in complex lateral sinus DAVFs and examine its efficacy and safety. METHODS: We retrospectively examined patients diagnosed with type IIa+b DAVF in the transverse or sigmoid sinus with associated venous sinus occlusion who were treated via stent placement between April 2017 and June 2019. RESULTS: Six patients were included in this study. Three patients had DAVFs in both the transverse and sigmoid sinuses, two in the transverse sinus and confluence of sinuses, and one in the transverse sinus. The most common symptoms were headache, dizziness, and limb weakness. At the last follow-up, three patients had significant improvement, and three were asymptomatic. Angiograms performed immediately after the surgery showed restoration of the anterograde venous drainage in all patients. According to the follow-up angiography results, two DAVFs were completely obliterated, and four remained as stable type I DAVFs. Most patients had satisfactory venous sinus drainage, except one who had in-stent stenosis. CONCLUSIONS: Stent placement can restore sinus patency, improve clinical symptoms, and decrease intracranial hemorrhage risk. This approach may be an effective option for treating type IIa+b lateral DAVFs complicated by sinus occlusion.


Assuntos
Malformações Vasculares do Sistema Nervoso Central , Cavidades Cranianas , Stents , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Malformações Vasculares do Sistema Nervoso Central/complicações , Malformações Vasculares do Sistema Nervoso Central/cirurgia , Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Idoso , Estudos Retrospectivos , Cavidades Cranianas/cirurgia , Cavidades Cranianas/diagnóstico por imagem , Adulto , Resultado do Tratamento , Seios Transversos/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Procedimentos Endovasculares/métodos
6.
Mol Plant ; 17(8): 1272-1288, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38956872

RESUMO

The discovery of a wild abortive-type (WA) cytoplasmic male sterile (CMS) line and breeding its restorer line have led to the commercialization of three-line hybrid rice, contributing considerably to global food security. However, the molecular mechanisms underlying fertility abortion and the restoration of CMS-WA lines remain largely elusive. In this study, we cloned a restorer gene, Rf20, following a genome-wide association study analysis of the core parent lines of three-line hybrid rice. We found that Rf20 was present in all core parental lines, but different haplotypes and structural variants of its gene resulted in differences in Rf20 expression levels between sterile and restored lines. Rf20 could restore pollen fertility in the CMS-WA line and was found to be responsible for fertility restoration in some CMS lines under high temperatures. In addition, we found that Rf20 encodes a pentatricopeptide repeat protein that competes with WA352 for binding with COX11. This interaction enhances COX11's function as a scavenger of reactive oxygen species, which in turn restores pollen fertility. Collectively, our study suggests a new action mode for pentatricopeptide repeat proteins in the fertility restoration of CMS lines, providing an essential theoretical basis for breeding robust restorer lines and for overcoming high temperature-induced fertility recovery of some CMS lines.


Assuntos
Oryza , Infertilidade das Plantas , Proteínas de Plantas , Pólen , Oryza/genética , Oryza/fisiologia , Infertilidade das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pólen/genética , Fertilidade/genética , Citoplasma/metabolismo , Citoplasma/genética , Genes de Plantas , Estudo de Associação Genômica Ampla , Regulação da Expressão Gênica de Plantas
7.
Dalton Trans ; 53(13): 5749-5769, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38441123

RESUMO

With the rapidly growing demand for clean energy and energy interconnection, there is an urgent need for rapid and high-capacity energy storage technologies to realize large-scale energy storage, transfer energy, and establish the energy internet. Supercapacitors, which have advantages such as high specific capacitance, fast charging and discharging rates, and long cycle lifetimes, are being widely used in electric vehicles, information technology, aerospace, and other fields. The performance of supercapacitors is crucially dependent on electrode materials. These can be categorized into electric double-layer capacitors and pseudocapacitors, primarily made from carbon and transition metal oxides, respectively. However, effectively monitoring the physicochemical properties of electrode materials during preparation and processing is challenging, which limits the improvement of supercapacitors' performance. Plasma materials preparation technology can effectively affect the materials preparation processing by energetic electrons, ions, free radicals, and multiple effects in plasma, which are easily manipulated by operation parameters. Therefore, plasma material preparation technology is considered a promising method to precisely monitor the physicochemical and electrochemical properties of energy storage materials and has been widely studied. This paper provides an overview of plasma materials preparation mechanisms, and details of the plasma technology application in the preparation of transition metal hybrids, carbon, and composite electrode materials, as well as a comparison with traditional methods. In conclusion, the advantages, challenges, and research directions of plasma materials preparation technology in the field of electrode materials preparation are summarized.

8.
Stroke ; 55(5): 1339-1348, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38511314

RESUMO

BACKGROUND: Evaluating rupture risk in cerebral arteriovenous malformations currently lacks quantitative hemodynamic and angioarchitectural features necessary for predicting subsequent hemorrhage. We aimed to derive rupture-related hemodynamic and angioarchitectural features of arteriovenous malformations and construct an ensemble model for predicting subsequent hemorrhage. METHODS: This retrospective study included 3 data sets, as follows: training and test data sets comprising consecutive patients with untreated cerebral arteriovenous malformations who were admitted from January 2015 to June 2022 and a validation data set comprising patients with unruptured arteriovenous malformations who received conservative treatment between January 2009 and December 2014. We extracted rupture-related features and developed logistic regression (clinical features), decision tree (hemodynamic features), and support vector machine (angioarchitectural features) models. These 3 models were combined into an ensemble model using a weighted soft-voting strategy. The performance of the models in discriminating ruptured arteriovenous malformations and predicting subsequent hemorrhage was evaluated with confusion matrix-related metrics in the test and validation data sets. RESULTS: A total of 896 patients (mean±SD age, 28±14 years; 404 women) were evaluated, with 632, 158, and 106 patients in the training, test, and validation data sets, respectively. From the training set, 9 clinical, 10 hemodynamic, and 2912 pixel-based angioarchitectural features were extracted. A logistic regression model was built using 4 selected clinical features (age, nidus size, location, and venous aneurysm), whereas a decision-tree model was constructed from 4 hemodynamic features (outflow time, stasis index, cerebral blood flow, and outflow volume ratio). A support vector machine model was designed using 5 pixel-based angioarchitectural features. In the validation data set, the accuracy, sensitivity, specificity, and area under the curve of the ensemble model for predicting subsequent hemorrhages were 0.840, 0.889, 0.823, and 0.911, respectively. CONCLUSIONS: The ensemble model incorporating clinical, hemodynamic, and angioarchitectural features showed favorable performance in predicting subsequent hemorrhage of cerebral arteriovenous malformations.

9.
Mol Breed ; 44(3): 17, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38371313

RESUMO

Heading date is one of the important agronomic traits that affects rice yield. In this study, we cloned a new rice B3 family gene, OsL1, which regulates rice heading date. Importantly, osl1-1 and osl1-2, two different types of mutants of OsL1 were created using the gene editing technology CRISPR/Cas9 system and exhibited 4 days earlier heading date than that of the wild type under short-day conditions. Subsequently, the plants overexpressing OsL1, OE-OsL1, showed a 2-day later heading date than the wild type in Changsha and a 5-day later heading date in Lingshui, but there was no significant difference in other yield traits. Moreover, the results of subcellular localization study indicated that OsL1 protein was located in the nucleus and the expression pattern analysis showed that OsL1 gene was expressed in rice roots, stems, leaves, and panicles, and the expression level was higher at the root and weak green panicle. In addition, the OsL1 gene was mainly expressed at night time under short-light conditions. The transcriptomic analysis indicated that OsL1 might be involved in the Hd1-Hd3a pathway function. Together, our results revealed that the cloning and functional analysis of OsL1 can provide new strategy for molecular design breeding of rice with suitable fertility period. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01444-1.

10.
Nano Lett ; 23(23): 11051-11056, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38088140

RESUMO

Terahertz (THz) field enhancement has significant applications in high-resolution imaging, next-generation wireless communications, and networking. In this work, we experimentally demonstrate a graphene metasurface for THz field enhancement that is based on the intervalley scattering theory. Each meta-atom of the metasurface is composed of one split-ring resonator (SRR) embedded in one graphene patch. The experimental results show that, by electrically adjusting the conductivity of the graphene patch, the THz field through the entire sample is enhanced by 23 times and the transmission amplitude at 0.47 THz decreases 8.4 dB. Moreover, the maximum phase difference at 0.43 THz reaches 88°. The experiment shows good agreement with simulation. This study paves a way for exploring THz-matter interactions and nonlinear optics.

11.
J Neurointerv Surg ; 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38050150

RESUMO

BACKGROUND: Angioplasty and/or stenting is a rescue therapy for mechanical thrombectomy (MT) in acute intracranial large vessel occlusion. This study was undertaken to determine whether rescue angioplasty and/or stenting improves the outcome after MT and to investigate whether outcomes differ by subgroup of rescue indication. METHODS: We performed propensity score matching (PSM) with data from a prospective multicenter registry of patients with acute large vessel occlusion receiving endovascular treatment. Patients were divided into the MT alone group and the MT with rescue therapy group. The primary outcome was functional independence (modified Rankin Scale score of 0-2) at 90 days. PSM was also performed in the failed MT (modified Thrombolysis In Cerebral Infarction (mTICI) 0-2a) and the residual severe stenosis (mTICI 2b-3) subgroups, respectively. RESULTS: 326 patients of mean±SD age 62.7±12.0 years (90 women, 27.6%) were matched from 1274 patients. In the matched cohort, functional independence at 90 days was higher in the rescue therapy group than in the MT alone group (44.2% vs 29.5%; OR 1.90, 95% CI 1.18 to 3.06, P=0.008). In the failed MT subgroup with 66 matched pairs, more patients had functional independence in the rescue therapy group than in the MT alone group (39.0% vs 17.0%; OR 3.12, 95% CI 1.29 to 7.59, P=0.01). In the residual stenosis subgroup with 63 matched pairs, functional independence rates were similar in the rescue therapy and the MT alone groups (51.6% vs 55.7%; OR 0.85, 95% CI 0.42 to 1.72, P=0.65). CONCLUSION: Rescue angioplasty and/or stenting could improve the clinical outcome in patients with acute large vessel occlusion with failed MT, while no benefit was seen in those with residual severe stenosis but substantial reperfusion.

12.
Appl Opt ; 62(33): 8905-8910, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38038036

RESUMO

We propose a polarization insensitive, flexible ultra-broadband terahertz (THz) metamaterial absorber. It consists of a chromium composite resonator on the top, a polyimide (PI) dielectric layer in the middle, and a chromium substrate. The simulation results show that the absorption achieves more than 90% ultra-wideband absorption in the range of 1.92-4.34 THz. The broadband absorption is produced by the combination of electric dipole resonance and magnetic resonance, as well as impedance matching with free space. Due to the rotational symmetry of the unit structure, the absorber is insensitive to polarization of the THz wave and has a larger range of incident angles. The total thickness of the absorber is only 13.4 µm, showing highly flexible and excellent high-temperature resistance characteristics. Therefore, it has potential applications in THz wave stealth and electromagnetic shielding.

13.
Front Neurol ; 14: 1174245, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37654429

RESUMO

Background: Patients with untreated cerebral arteriovenous malformations (AVMs) are at risk of intracerebral hemorrhage. However, treatment to prevent AVM hemorrhage carries risks. Objective: This study aimed to analyze the AVM nidus-related hemodynamic features and identify the risk factors for subsequent hemorrhage. Methods: We retrospectively identified patients with untreated AVMs who were assessed at our institution between March 2010 and March 2021. Patients with ≥6 months of treatment-free and hemorrhage-free follow-up after diagnosed by digital subtraction angiography were included in subsequent examinations. The hemodynamic features were extracted from five contrast flow-related parameter maps. The Kaplan-Meier analyses and Cox proportional hazards regression models were used to find the potential risk factors for subsequent hemorrhage. Results: Overall, 104 patients with a mean follow-up duration of 3.37 years (median, 2.42 years; range, 6-117 months) were included in study, and the annual risk of rupture was 3.7%. Previous rupture (hazard ratio [HR], 4.89; 95% confidence interval [CI], 1.16-20.72), deep AVM location (HR, 4.02; 95% CI, 1.01-15.99), higher cerebral blood volume (HR, 3.35; 95% CI, 1.15-9.74) in the nidus, and higher stasis index (HR, 1.54; 95% CI, 1.06-2.24) in the nidus were associated with subsequent hemorrhage in untreated AVMs. Conclusion: Higher cerebral blood volume and stasis index in the nidus suggest increased blood inflow and stagnant blood drainage. The combination of these factors may cause subsequent hemorrhage of AVMs.

14.
Opt Lett ; 48(18): 4781-4784, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37707901

RESUMO

Slow light devices have significant applications in memory, switching, and quantum optics. However, the design and fabrication of slow light devices with large tunable group delay are still challenging. Here, a graphene-based slow light device that can electrically modulate the group delay of terahertz (THz) waves is proposed and experimentally demonstrated. The unit cell of the device consists of a U-shaped metal resonator and an Ω-shaped metal resonator, with three graphene ribbons embedded between the two resonators. Under electrical stimuli, a relatively high amplitude modulation depth of 74% is achieved and the maximum transmission amplitude is as high as 0.7 at the transmission peak of 0.6 THz. Most importantly, the maximum group delay variation reaches 5 ps at 0.76 THz and the maximum group delay amplitude is as high as 8.8 ps. The experiment shows good agreement with simulation. This study paves a new way for developing novel switchable nanophotonic devices and slow light devices.

15.
Front Aging Neurosci ; 15: 1029515, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143689

RESUMO

Background and objectives: Regarding the anti-inflammatory effect, methylprednisolone is a candidate to prevent patients with unruptured intracranial aneurysms (UIAs) from postoperative bleeding (PB) after flow diverter (FD) treatment. This study aimed to investigate whether methylprednisolone is related to a lower incidence of PB after FD treatment for UIAs. Methods: This study retrospectively reviewed UIA patients receiving FD treatment between October 2015 and July 2021. All patients were observed until 72 h after FD treatment. The patients receiving methylprednisolone (80 mg, bid, for at least 24 h) were considered as standard methylprednisolone treatment (SMT) users, otherwise as non-SMT users. The primary endpoint indicated the occurrence of PB, including subarachnoid hemorrhage, intracerebral hemorrhage, and ventricular bleeding, within 72 h after FD treatment. This study compared the incidence of PB between SMT users and non-SMT users and investigated the protective effect of SMT on PB after FD treatment using the Cox regression model. Finally, after controlling the potential factors related to PB, we performed subgroup analysis to further confirm the protective effect of SMT on PB. Results: This study finally included 262 UIA patients receiving FD treatment. PB occurred in 11 patients (4.2%), and 116 patients (44.3%) received SMT postoperatively. The median time from the end of surgery to PB was 12.3 h (range: 0.5-48.0 h). SMT users had a lower incidence of PB comparing with non-SMT users (1/116, 0.9% vs. 10/146, 6.8%, respectively; p = 0.017). The multivariate Cox analysis demonstrated that SMT users (HR, 0.12 [95%CI, 0.02-0.94], p = 0.044) had a lower risk of PB postoperatively. After controlling the potential factors related to PB (i.e., gender, irregular shape, surgical methods [FD and FD + coil] and UIA sizes), the patients receiving SMT still had a lower cumulative incidence of PB, comparing with patients receiving non-SMT (all p < 0.05). Conclusion: SMT was correlated with the lower incidence of PB for patients receiving FD treatment and may be a potential method to prevent PB after the FD treatment.

16.
Front Neurol ; 14: 1118980, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37006480

RESUMO

Objective: Although alcohol flushing syndrome (AFS) has been associated with various diseases, its association with intracranial aneurysm rupture (IAR) is unclear. We aimed to examine this association in the Chinese Han population. Methods: We retrospectively reviewed Chinese Han patients with intracranial aneurysms who were evaluated and treated at our institution between January 2020 and December 2021. AFS was determined using a semi-structured telephone interview. Clinical data and aneurysm characteristics were assessed. Univariate and multivariate logistic regression were conducted to determine independent factors associated with aneurysmal rupture. Results: A total of 1,170 patients with 1,059 unruptured and 236 ruptured aneurysms were included. The incidence of aneurysm rupture was significantly higher in patients without AFS (p < 0.001). Meanwhile, there was a significantly difference between the AFS and non-AFS group in habitual alcohol consumption (10.5 vs. 27.2%, p < 0.001). In the univariate analyses, AFS [odds ratio (OR) 0.49; 95% confidence interval (CI), 0.34-0.72] was significantly associated with IAR. In the multivariate analysis, AFS was an independent predictor of IAR (OR 0.50; 95%, CI, 0.35-0.71). Multivariate analysis revealed that AFS was an independent predictor of IAR in both habitual (OR 0.11; 95% CI, 0.03-0.45) and non-habitual drinkers (OR 0.69; 95% CI, 0.49-0.96). Conclusion: Alcohol flushing syndrome may be a novel clinical marker to assess the risk of IAR. The association between AFS and IAR exists independently of alcohol consumption. Further single nucleotide polymorphism testing and molecular biology studies are warranted.

18.
Nat Commun ; 14(1): 1305, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36894566

RESUMO

Intrahepatic cholestasis of pregnancy (ICP) is a female pregnancy-specific disorder that is characterized by increased serum bile acid and adverse fetal outcomes. The aetiology and mechanism of ICP are poorly understood; thus, existing therapies have been largely empiric. Here we show that the gut microbiome differed significantly between individuals with ICP and healthy pregnant women, and that colonization with gut microbiome from ICP patients was sufficient to induce cholestasis in mice. The gut microbiomes of ICP patients were primarily characterized by Bacteroides fragilis (B. fragilis), and B. fragilis was able to promote ICP by inhibiting FXR signaling via its BSH activity to modulate bile acid metabolism. B. fragilis-mediated FXR signaling inhibition was responsible for excessive bile acid synthesis and interrupted hepatic bile excretion to ultimately promote the initiation of ICP. We propose that modulation of the gut microbiota-bile acid-FXR axis may be of value for ICP treatment.


Assuntos
Colestase Intra-Hepática , Microbioma Gastrointestinal , Complicações na Gravidez , Feminino , Gravidez , Humanos , Animais , Camundongos , Complicações na Gravidez/metabolismo , Ácidos e Sais Biliares
19.
Materials (Basel) ; 16(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36984352

RESUMO

The impact response of a composite structure consisting of a metal-packaged ceramic interlayer and an ultra-high molecular weight polyethylene (UHMWPE) laminate has been studied through a ballistic test and numerical simulation. The studied structure exhibits 50% higher anti-penetration performance than the traditional ceramic/metal structure with the same areal density. The metal-packaged ceramic interlayer and the UHMWPE laminate are key components in resisting the penetration. By using a metal frame to impose three-dimensional constraints on ceramic tiles, the metal-packaged ceramic interlayer can limit the crushing of the ceramic and contain the broken ceramic fragment to improve the erosion of the projectile. The large deformation of UHMWPE laminate absorbs a large amount of energy from the projectile. By decreasing the amplitude of the shock wave and changing the distribution of the impact load in the structure, the projectile has longer residence time on the interlayer. The anti-penetration performance shows within 10% variation when the impact position is varied. Due to the asymmetric deformation and high elastic recovery ability of the UHMWPE laminate, the projectile trajectory deflection is increased, and the broken ceramic fragments are restrained, thereby mitigating after-effect damage caused by the projectile after penetrating the structure.

20.
Appl Opt ; 62(4): 1103-1108, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36821170

RESUMO

Actively controlling the phase of a terahertz (THz) wave is of great significance for beaming, tunable focusing, and holography. We present a THz phase modulator based on an electrically triggered vanadium dioxide (V O 2) reconfigurable metasurface. The unit cell of the device consists of two split-ring resonators embedded with a V O 2 ribbon. By electrically triggering the insulator-to-metal transition of V O 2, the resonance mode and resonance intensity of the unit cell can be dynamically controlled. The simulation results show that the structure can achieve a phase shift of about 360° in the range of 1.03-1.13 THz, and the reflection amplitude can reach 80%. The device has potential applications in THz imaging, radar, broadband wireless communications, and array phase control.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA