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1.
ACS Appl Mater Interfaces ; 16(23): 30443-30452, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38815155

ABSTRACT

Optical fiber force sensing has attracted considerable interest in biological, materials science, micromanipulation, and medical applications owing to its compact and cost-efficient configuration. However, the glass fiber has an intrinsic high Young's modulus, resulting in force sensors being generally less sensitive. While hyperelastic polymer materials can be utilized to enhance the force sensitivity, the thermodynamic properties of the polymer may weaken the sensing accuracy and reliability. Herein, we demonstrate ultracompact three-dimensional (3D)-printed multicore fiber (MCF) tip probes for simultaneous measurement of nanoforce and temperature with high sensitivity. The sensor is highly sensitive to force-induced deformation due to the special geometric features of the polymer microcantilever, and the high-temperature sensitivity can be implemented through the poly(dimethylsiloxane) (PDMS) microcavity on the same fiber facet. Moreover, the sensitivities of the fiber interferometers are remarkably enhanced by introducing the optical analogue of the Vernier effect. Such a device exhibits a force sensitivity of 56.35 nm/µN, which is more than 103 times that of all-silica fiber force sensors. The PDMS microcavity provides a temperature sensitivity of 1.447 nm/°C, measuring the local temperature of the probe and compensating for temperature crosstalk of the force detection. The proposed compact MCF-tip sensor can simultaneously measure nanoforce and temperature with high sensitivity, facilitating multiparameter sensing in a restricted space environment and showing the potential in miniaturized all-fiber multiparameter sensors.

2.
Opt Lett ; 49(10): 2765-2768, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38748156

ABSTRACT

In this Letter, a quasi-distributed quartz enhanced photoacoustic spectroscopy (QEPAS) gas sensing system based on hollow waveguide micropores (HWGMP) was reported for the first time, to the best of our knowledge. Three micropores were developed on the HWG to achieve distributed detection units. Three self-designed quartz tuning forks (QTFs) with low resonant frequency of 8.7 kHz were selected as the acoustic wave transducer to improve the detection performance. Compared with micro-nano fiber evanescent wave (FEW) QEPAS, the HWGMP-QEPAS sensor has advantages such as strong anti-interference ability, low loss, and low cost. Acetylene (C2H2) was selected as the target gas to verify the characteristics of the reported sensor. The experimental results showed that the three QTFs almost had the same sensing ability and possessed an excellent linear concentration response to C2H2. The minimum detection limits (MDLs) for the three QTFs were determined as 68.90, 68.31, and 66.62 ppm, respectively. Allan deviation analysis indicated that the system had good long-term stability, and the MDL can be improved below 3 ppm in an average time of 1000 s.

3.
Article in English | MEDLINE | ID: mdl-38781485

ABSTRACT

BACKGROUND AND OBJECTIVES: Lateralization or mobilization of the internal carotid artery (ICA) during a midline approach is required to expose lesions behind or lateral to the ICA. However, there have been no published data regarding the surgical outcomes of the endoscopic endonasal internal carotid transposition technique (EEITT). This study aimed to analyze the relevant surgical anatomy around the ICA and propose a grading scheme of EEITT. METHODS: A retrospective review of patients who underwent EEITT at a single institution was performed. Based on structures that limited the ICA and intraoperative findings, an anatomically surgical grading scheme of EEITT was proposed. RESULTS: Forty-two patients (mean age 45.6 years, 57.1% female patients) were included. Of them, 29 cases (69.0%) were Knosp grade 4 pituitary adenoma, 6 cases (14.3%) were chordoma, 6 cases (14.3%) were meningioma, and a single case (2.4%) was meningeal IgG4-related disease. The EEITT was categorized into Grades 1, 2 and 3, which was used in 24 (57.1%), 12 (28.6%), and 6 (14.3%) cases, respectively. The most common symptom was visual disturbance (45.2%). The gross total resection rate in Grade 1 (79.2%) and Grade 2 (83.3%) was much higher than that in Grade 3 (66.6%). The overall rate of visual function improvement, preoperative cranial nerve (CN) palsy improvement, and postoperative hormonal remission was 89.4%, 85.7%, and 88.9%, respectively. The rate for the following morbidities was cerebrospinal fluid leakage, 2.4%; permanent diabetes insipidus, 4.8%; new transient CN palsy, 9.5%; permanent CN palsy, 4.7%; panhypopituitarism, 7.1%; and ICA injury, 2.4%. CONCLUSION: The EEITT is technically feasible and could be graded according to the extent of disconnection of limiting structures. For complex tumor with parasellar extensions, the distinction into Grades 1, 2, and 3 will be of benefit to clinicians in predicting risks, avoiding complications, and generating tailored individualized surgical strategies.

4.
J Neurosurg ; : 1-11, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38669701

ABSTRACT

OBJECTIVE: Tumors located in the retrochiasmatic region with extension to the third ventricle might be difficult to access when the pituitary-chiasmatic corridor is narrow. Similarly, tumor extension into the interpeduncular and retrosellar space poses a major surgical challenge. Pituitary transposition techniques have been developed to gain additional access. However, when preoperative pituitary function is already impaired or the risk of postoperative panhypopituitarism (PH) is considered to be particularly high, removal of the pituitary gland (PG) might be the preferred option to increase the working corridor. The aim of this study was to describe the relevant surgical anatomy, operative steps, and clinical experience with the endoscopic endonasal pituitary sacrifice (EEPS) and transsellar approach. METHODS: This study comprised anatomical dissections to highlight the relevant surgical steps and a retrospective case series reporting clinical characteristics, indications, and outcomes of patients who underwent EEPS. The surgical technique is as follows: both lateral opticocarotid recesses are exposed laterally, the limbus sphenoidale superiorly, and the sellar floor inferiorly. After opening the dura, the PG is detached circumferentially and mobilized off the medial walls of the cavernous sinuses. The descending branches of the superior hypophyseal artery are coagulated, and the stalk is transected. After removal of the PG, drilling of the dorsum sellae and bilateral posterior clinoidectomies are performed to gain access to the hypothalamic region, interpeduncular, and prepontine cisterns. RESULTS: From 2018 to 2023, 11 patients underwent EEPS. The cohort comprised mostly tuberoinfundibular craniopharyngiomas (n = 8, 73%). Seven (64%) patients had partial or complete anterior PG dysfunction preoperatively, while 4 (36%) had preoperative diabetes insipidus. Because of the specific tumor configuration, the chance of preserving endocrine function was estimated to be very low in patients with intact function. The main reasons for pituitary sacrifice were impaired visibility and surgical accessibility to the retrochiasmatic and retrosellar spaces. Gross-total tumor resection was achieved in 10 (91%) patients and near-total resection in 1 (9%) patient. Two (18%) patients experienced a postoperative CSF leak, requiring surgical revision. CONCLUSIONS: When preoperative pituitary function is already impaired or the risk for postoperative PH is considered particularly high, the EEPS and transsellar approach appears to be a feasible surgical option to improve visibility and accessibility to the retrochiasmatic hypothalamic and retrosellar spaces, thus increasing tumor resectability.

5.
Photoacoustics ; 36: 100594, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38375332

ABSTRACT

In this article, a mid-infrared all-fiber light-induced thermoelastic spectroscopy (LITES) sensor based on a hollow-core anti-resonant fiber (HC-ARF) was reported for the first time. The HC-ARF was applied as a light transmission medium and gas chamber. The constructed all-fiber structure has merits of low loss, easy optical alignment, good system stability, reduced sensor size and cost. The mid-infrared transmission structure can be utilized to target the strongest gas absorption lines. The reversely-tapered SM1950 fiber and the HC-ARF were spatially butt-coupled with a V-shaped groove between the two fibers to facilitate gas entry. Carbon monoxide (CO) with an absorption line at 4291.50 cm-1 (2.33 µm) was chosen as the target gas to verify the sensing performance. The experimental results showed that the all-fiber LITES sensor based on HC-ARF had an excellent linear response to CO concentration. Allan deviation analysis indicated that the system had excellent long-term stability. A minimum detection limit (MDL) of 3.85 ppm can be obtained when the average time was 100 s.

6.
Micromachines (Basel) ; 15(1)2024 Jan 07.
Article in English | MEDLINE | ID: mdl-38258227

ABSTRACT

We optimized and fabricated an ultra-bend-resistant 4-core simplex cable (SXC) employing 4-core multicore fiber (MCF) suitable for short-reach dense spatial division multiplexing (DSDM) optical transmission in the O-band. The characteristics of transmission loss, macro-bending and cross-talk (XT) between adjacent cores after cabling were firstly clarified. By introducing the trapezoid index and optimizing the cabling process, the maximum values of added XT of 1.17 dB/km due to 10 loops with a bending radius of 6 mm imposed over the 4-core SXC and a macro-bending loss of 0.37 dB/10 turns were, respectively, achieved.P Then, the optical transmission with low bit error rate (BER) was presented using a 100GBASE-LR4 transceiver over the 1.2 km long 4-core SXC. The excellent bending resistance of the 4-core SXC may pave the way for a reduction in space pressure and increase in access density on short-reach optical interconnect (OI) based on DSDM.

7.
Opt Lett ; 48(11): 2821-2824, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37262219

ABSTRACT

The nanobore fiber (NBF) is a promising nanoscale optofluidic platform due to its long nanochannel and unique optical properties. However, so far, the applications of NBF have been based only on its original fiber geometry without any extra functionalities, in contrast with various telecom fiber devices, which may limit its wide applications. Here, we provide the first, to the best of our knowledge, demonstration of NBF-based fiber Bragg gratings (FBGs) introduced by either the femtosecond (fs) laser direct writing technique or the ultraviolet (UV) laser phase mask technique. Moreover, the FBG fabricated via the UV laser was optimized, achieving a high reflectivity of 96.89% and simultaneously preserving the open nanochannel. The NBF-based FBGs were characterized in terms of temperature variation and the infiltration of different liquids, and they showed high potential for nanofluidic applications.

8.
Opt Lett ; 48(5): 1120-1123, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36857228

ABSTRACT

The Fresnel reflection of a splice from the air-silica interface between a hollow-core fiber (HCF) and a solid-core conventional fiber will increase the splicing loss and also cause possible instability of transmission. Here, for the first time, we develop a novel approach to fusion splicing an antireflection-coated (AR-coated) conventional fiber and an antiresonant HCF, which was generally claimed to be impossible because of the heat-induced damage of the coating, and achieve state-of-the-art ultralow fusion splicing loss less than 0.3 dB and a low return loss less than -28 dB by optimizing the splicing procedures and parameters. Our new fusion splicing approach will benefit the wide application of HCFs in telecoms, laser technologies, gyroscopes, and fiber gas cells.

9.
Front Immunol ; 14: 1103592, 2023.
Article in English | MEDLINE | ID: mdl-36999040

ABSTRACT

Atherosclerosis (AS) is a chronic inflammatory disease, involving a pathological process of endothelial dysfunction, lipid deposition, plaque rupture, and arterial occlusion, and is one of the leading causes of death in the world population. The progression of AS is closely associated with several inflammatory diseases, among which periodontitis has been shown to increase the risk of AS. Porphyromonas gingivalis (P. gingivalis), presenting in large numbers in subgingival plaque biofilms, is the "dominant flora" in periodontitis, and its multiple virulence factors are important in stimulating host immunity. Therefore, it is significant to elucidate the potential mechanism and association between P. gingivalis and AS to prevent and treat AS. By summarizing the existing studies, we found that P. gingivalis promotes the progression of AS through multiple immune pathways. P. gingivalis can escape host immune clearance and, in various forms, circulate with blood and lymph and colonize arterial vessel walls, directly inducing local inflammation in blood vessels. It also induces the production of systemic inflammatory mediators and autoimmune antibodies, disrupts the serum lipid profile, and thus promotes the progression of AS. In this paper, we summarize the recent evidence (including clinical studies and animal studies) on the correlation between P. gingivalis and AS, and describe the specific immune mechanisms by which P. gingivalis promotes AS progression from three aspects (immune escape, blood circulation, and lymphatic circulation), providing new insights into the prevention and treatment of AS by suppressing periodontal pathogenic bacteria.


Subject(s)
Atherosclerosis , Periodontitis , Animals , Porphyromonas gingivalis , Periodontitis/microbiology , Inflammation , Lipids
10.
Mol Neurobiol ; 60(5): 2801-2818, 2023 May.
Article in English | MEDLINE | ID: mdl-36732429

ABSTRACT

Extracellular vesicle (EV)-encapsulated circRNAs have the potential role in affecting brain disorders. However, the role of circ_0000075 in cerebral ischemic injury remains unclear. Here, we tried to investigate the mechanism of bone marrow mesenchymal stem cell (BMSC)-derived EVs carrying circ_0000075 in the control of cerebral ischemic injury. Initially, a mouse model with cerebral ischemic injury was induced by middle cerebral artery occlusion (MCAO), followed by the determination of circ_0000075 expression. Then, neurons were isolated and subjected to oxygen-glucose deprivation/reperfusion. BMSCs were isolated for extraction of EVs. The correlation among circ_0000075, microRNA (miR)-218-5p, and Smad ubiquitination regulatory factor 2 (SMURF2) was detected with their roles in cerebral ischemic injury analyzed in vivo and in vitro. circ_0000075 was down-regulated in MCAO mice and engineered RVG-EVs were internalized by neurons to up-regulate circ_0000075 expression. Treatment of RVG-circ_0000075-EVs reduced brain tissue damage, increased neuronal count, and significantly curtailed apoptosis rate, suppressing cerebral ischemic injury in vitro and in vivo. miR-218-5p was targeted by circ_0000075 in neurons, which promoted SMURF2 expression. A negative correlation between SMURF2 and transcriptional regulator Yin Yang 1 (YY1) was identified. In vitro experiments further proved that circ_ 00,000 75 could down-regulate the expression of YY1 through SMURF2, and finally relieving cerebral ischemic injury. Collectively, engineered EVs delivered circ_0000075 into brain tissues and increased circ_0000075 expression, which down-regulated miR-218-5p and up-regulated SMURF2, thus alleviating cerebral ischemic injury.


Subject(s)
Brain Injuries , Extracellular Vesicles , Mesenchymal Stem Cells , MicroRNAs , Animals , Mice , Ubiquitin-Protein Ligases/genetics , MicroRNAs/genetics
11.
Neurosurgery ; 92(1): 213-222, 2023 01 01.
Article in English | MEDLINE | ID: mdl-36519865

ABSTRACT

BACKGROUND: Understanding the growth pathway of Knosp grade 4 pituitary adenoma (KG4PA) has a direct impact on surgical planning and safety for tumor eviction. OBJECTIVE: To analyze the different characteristics between KG4PAs with a focus on the tumor growth pathway and its relationship to the cavernous segment of internal carotid artery. METHODS: Clinical data from 129 patients with KG4PAs who underwent endoscopic endonasal surgery were retrospectively reviewed. A subclassification scheme was proposed based on the tumor growth pathway and its relevant features. The clinical connotation of the subclassification on surgical outcomes was also analyzed. RESULTS: The KG4PAs were classified into 3 types based on the tumor growth pathway and its relevant features: groups A, B, and AB. The gross total resection rate in group A (51.2%) was much lower than that in group B (87.5%) and AB (87%) with a significant difference between the 3 groups ( P = .0004). The overall rate of visual function improvement, preoperative cranial nerve (CN) palsy improvement, and postoperative hormonal remission was 85.1%, 83.3%, and 85.7%, respectively. The rate of transient CN palsy, permanent CN palsy, permanent diabetes insipidus, panhypopituitarism, CSF leakage, and internal carotid artery injury was 7.8%, 3.9%, 4.7%, 2.3%, 1.5%, and 0.7%, respectively. CONCLUSION: The subclassification strengthens our understanding of KG4PAs on tumor growth corridors and topographic relations of tumor and cavernous segment of internal carotid artery. Furthermore, the distinction into groups 4A, 4B, and 4AB is of benefits for selecting approaches, predicting risk and avoiding complications, and generating more tailored individualized surgical strategies for KG4PAs with better outcomes.


Subject(s)
Adenoma , Natural Orifice Endoscopic Surgery , Pituitary Neoplasms , Humans , Pituitary Neoplasms/surgery , Pituitary Neoplasms/pathology , Retrospective Studies , Adenoma/surgery , Adenoma/pathology , Paralysis , Treatment Outcome
12.
Opt Express ; 30(11): 18044-18053, 2022 May 23.
Article in English | MEDLINE | ID: mdl-36221612

ABSTRACT

Hybrid optical fibers have been widely investigated in different architectures to build integrated fiber photonic devices and achieve various applications. Here we proposed and fabricated hybrid microfiber waveguides with self-growing polymer nanofilms on the surfaces of microfibers triggered by evanescent field of light for the first time. We have demonstrated the polymer nanofilm of ∼50 nm can be grown on the microfiber with length up to 15 mm. In addition, the roughness of nanofilm can be optimized by controlling the triggering laser power and exposure duration, and the total transmission loss of the fabricated hybrid microfiber is less than 2 dB within a wide wavelength range. The hybrid polymer nanofilm microfiber waveguides have been characterized and their relative humidity (RH) responses have also been tested, indicating a potential for RH sensing. Our fabrication method may also be extended to construct the hybrid microfibers with different functional photopolymer materials.

13.
Sci Adv ; 8(40): eabn9783, 2022 Oct 07.
Article in English | MEDLINE | ID: mdl-36206336

ABSTRACT

Quantum autoencoders serve as efficient means for quantum data compression. Here, we propose and demonstrate their use to reduce resource costs for quantum teleportation of subspaces in high-dimensional systems. We use a quantum autoencoder in a compress-teleport-decompress manner and report the first demonstration with qutrits using an integrated photonic platform for future scalability. The key strategy is to compress the dimensionality of input states by erasing redundant information and recover the initial states after chip-to-chip teleportation. Unsupervised machine learning is applied to train the on-chip autoencoder, enabling the compression and teleportation of any state from a high-dimensional subspace. Unknown states are decompressed at a high fidelity (~0.971), obtaining a total teleportation fidelity of ~0.894. Subspace encodings hold great potential as they support enhanced noise robustness and increased coherence. Laying the groundwork for machine learning techniques in quantum systems, our scheme opens previously unidentified paths toward high-dimensional quantum computing and networking.

14.
Micromachines (Basel) ; 13(10)2022 Oct 19.
Article in English | MEDLINE | ID: mdl-36296127

ABSTRACT

An optimized multi-step index (MSI) 2-LP-mode fiber is proposed and fabricated with low propagation loss of 0.179 dB/km, low intermodal crosstalk and excellent bend resistance. We experimentally clarified the characteristics of backward Brillouin scattering (BBS) and forward Brillouin scattering (FBS) induced by radial acoustic modes (R0,m) in the fabricated MSI 2-LP-mode fiber, respectively. Via the use of this two-mode fiber, we demonstrated a novel discriminative measurement method of temperature and acoustic impedance based on BBS and FBS, achieving improved experimental measurement uncertainties of 0.2 °C and 0.019 kg/(s·mm2) for optoacoustic chemical sensing. The low propagation loss of the sensing fiber and the new measurement method based on both BBS and FBS may pave the way for long-distance and high spatial resolution distributed fiber sensors.

15.
World Neurosurg ; 165: e128-e136, 2022 09.
Article in English | MEDLINE | ID: mdl-35680084

ABSTRACT

OBJECTIVES: We aimed to predict hematoma expansion in intracerebral hemorrhage (ICH) patients by using the deep learning technique. METHODS: We retrospectively collected data from ICH patients treated between May 2015 and May 2019. Head computed tomography (CT) scans were performed at admission, and 6 hours, 24 hours, and 72 hours after admission. CT scans were mandatory when neurologic deficits occurred. Univariate and multivariate analyses were conducted to illustrate the association between clinical variables and hematoma expansion. Convolutional neural network (CNN) was adopted to predict hematoma expansion based on brain CT slices. In addition, 5 machine learning methods, including support vector machine, multi-layer perceptron, naive Bayes, decision tree, and random forest, were also performed to predict hematoma expansion based on clinical variables for comparisons. RESULTS: A total of 223 patients were included. It was revealed that patients' older age (odds ratio [95% confidence interval]: 1.783 [1.417-1.924]), cerebral hemorrhage and breaking into the ventricle (2.524 [1.291-1.778]), coagulopathy (2.341 [1.677-3.454]), and baseline National Institutes of Health Stroke Scale (1.545 [1.132-3.203]) and Glasgow Coma Scale scores (0.782 [0.432-0.918]) independently associated with hematoma expanding. After 4-5 epochs, the CNN framework was well trained. The average sensitivity, specificity, and accuracy of CNN prediction are 0.9197, 0.8837, and 0.9058, respectively. Compared with 5 machine learning methods based on clinical variables, CNN can also achieve better performance. CONCLUSIONS: More than 90% of hematomas with or without expansion can be precisely classified by deep learning technology within this study, which is better than other methods based on clinical variables only. Deep learning technology could favorably predict hematoma expansion from non-contrast CT scan images.


Subject(s)
Deep Learning , Bayes Theorem , Brain , Cerebral Hemorrhage/complications , Cerebral Hemorrhage/diagnostic imaging , Disease Progression , Hematoma/complications , Hematoma/diagnostic imaging , Humans , Retrospective Studies
16.
Front Oncol ; 12: 847250, 2022.
Article in English | MEDLINE | ID: mdl-35719989

ABSTRACT

Objective: The surgical management of lesions involving the lateral area of the suprasellar region, including the lateral aspect of the planum sphenoidale and the tight junction region of the optic canal (OC), anterior clinoid process (ACP), and internal carotid artery (ICA) and its dural rings, is extremely challenging. Here, these regions, namely, the "parasuprasellar" area, are described from the endonasal perspective. Moreover, the authors introduce two novels endoscopic endonasal supraoptic (EESO) and endoscopic endonasal infraoptic (EEIO) approaches to access the parasuprasellar area. Methods: Surgical simulation of the EESO and EEIO approaches to the parasuprasellar area was conducted in 5 silicon-injected specimens. The same techniques were applied in 12 patients with lesions involving the parasuprasellar area. Results: The EESO approach provided excellent surgical access to the lateral region of the planum sphenoidale, which corresponds to the orbital gyrus of the frontal lobe. With stepwise bone (OC, optic strut and ACP) removal, dissociation of the ophthalmic artery (OA) and optic nerve (ON), the EEIO approach enables access to the lateral region of the supraclinoidal ICA. These approaches can be used independently or in combination, but are more often employed as a complement to the endoscopic endonasal midline and transcavernous approaches. In clinical application, the EESO and EEIO approaches were successfully performed in 12 patients harboring tumors as well as multiple aneurysms involving the parasuprasellar area. Gross total and subtotal tumor resection were achieved in 9 patients and 1 patient, respectively. For two patients with multiple aneurysms, the lesions were clipped selectively according to location and size. Visual acuity improved in 7 patients, remained stable in 4, and deteriorated in only 1. No postoperative intracranial infection or ICA injury occurred in this series. Conclusions: The EESO and EEIO approaches offer original treatment options for well-selected lesions involving the parasuprasellar area. They can be combined with the endoscopic endonasal midline and transcavernous approaches to remove extensive pathologies involving the intrasellar, suprasellar, sphenoid, and cavernous sinuses and even the bifurcation of the ICA. This work for the first time pushes the boundary of the endoscopic endonasal approach lateral to the supraclinoidal ICA and ON.

17.
Opt Express ; 30(5): 8317-8329, 2022 Feb 28.
Article in English | MEDLINE | ID: mdl-35299575

ABSTRACT

Optofluidic microlenses are one of the crucial components in many miniature lab-on-chip systems. However, many optofluidic microlenses are fabricated through complex micromachining and tuned by high-precision actuators. We propose a kind of tunable optofluidic microbubble lens that is made by the fuse-and-blow method with a fiber fusion splicer. The optical focusing properties of the microlens can be tuned by changing the refractive index of the liquid inside. The focal spot size is 2.8 µm and the focal length is 13.7 µm, which are better than those of other tunable optofluidic microlenses. The imaging capability of the optofluidic microbubble lens is demonstrated under a resolution test target and the imaging resolution can reach 1 µm. The results indicate that the optofluidic microbubble lens possesses good focusing properties and imaging capability for many applications, such as cell counting, optical trapping, spatial light coupling, beam shaping and imaging.


Subject(s)
Lenses , Microfluidic Analytical Techniques , Cell Count , Microbubbles , Refractometry
18.
Lab Invest ; 102(7): 691-701, 2022 07.
Article in English | MEDLINE | ID: mdl-35013529

ABSTRACT

Gliomas are the most common primary intracranial tumor, accounting for more than 70% of brain malignancies. Studies indicate that highly upregulated in liver cancer (HULC), a long noncoding RNA (lncRNA), functions as an oncogene in gliomas. However, the underlying mechanism of HULC in gliomas remains under-studied and was subsequently investigated in the current study. Brain tissues were clinically collected from 50 patients with glioblastoma (GBM) and 35 patients with acute craniocerebral injury, followed by immunohistochemical detection of the expression patterns of Forkhead box M1 (FOXM1), anterior gradient 2 (AGR2), and hypoxia-inducible factor-1α (HIF-1α). After flow cytometry-based sorting of the CD133+ glioma stem cells (GSCs) from the U251 cell line, the obtained cells were subjected to lentivirus infection. Afterwards, the proliferation, stemness, and apoptosis of GSCs were evaluated using sphere formation, immunofluorescence, and flow cytometry assays, respectively. In addition, the interactions among HULC, FOXM1, AGR2, and HIF-1α were identified using RNA immunoprecipitation (RIP), RNA pull-down, Chromatin immunoprecipitation (ChIP), IP, and dual luciferase reporter assays. Last, the specific effects were validated in vivo. HULC was upregulated in GBM tissues and GSCs, which may promote the progression of glioma. On the other hand, silencing of HULC reduced the stemness, inhibited the proliferation, and promoted the apoptosis and differentiation of GSCs. In addition, HULC further stabilized FOXM1 expression in GSCs through ubiquitination, while FOXM1 activated AGR2 transcription to promote HIF-1α expression. Moreover, HULC promoted the glycolysis and stemness of GSCs through its regulation of the FOXM1/AGR2/HIF-1α axis, consequently exacerbating the occurrence and development of glioma. The findings obtained in our study indicate that HULC stabilizes the FOXM1 protein by ubiquitination to upregulate the expression of AGR2 and HIF-1α, which further promote the glycolysis of and maintain the stemness of GSCs, to enhance the tumorigenicity of GSCs, highlighting a novel therapeutic target for glioma.


Subject(s)
Brain Neoplasms , Glioblastoma , Glioma , Neoplastic Stem Cells , RNA, Long Noncoding , Brain Neoplasms/genetics , Cell Line, Tumor , Cell Proliferation/genetics , Forkhead Box Protein M1/genetics , Forkhead Box Protein M1/metabolism , Gene Expression Regulation, Neoplastic , Glioblastoma/genetics , Glioma/genetics , Glycolysis , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Mucoproteins/genetics , Mucoproteins/metabolism , Oncogene Proteins/genetics , Oncogene Proteins/metabolism , RNA, Long Noncoding/genetics
19.
Neurosurg Rev ; 45(2): 1111-1122, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34647222

ABSTRACT

Ventriculoatrial shunts are the most common second-line procedure for cases in which ventriculoperitoneal shunts are unsuitable. Shunting-associated thrombosis is a potentially life-threatening complication after ventriculoatrial shunt insertion. The overall prevalence of this complication is still controversial because of substantial differences in the numbers found in studies using clinical data and in those analyzing postmortem findings. The etiology of thrombosis may be multifactorial, including shunt catheter itself, contents of cerebrospinal fluid, shunt infection, and genetic disorder. The clinical presentation can vary widely, ranging from asymptomatic to a life-threatening condition. Timely recognition of thromboembolic lesions is critical for treatment. However, early diagnosis and management is still challenging because of a relatively long asymptomatic latency and lack of clear guideline recommendations. The purpose of this review is to provide an overview of ventriculoatrial shunt thrombosis, especially to focus on its etiopathogenesis, diagnosis, treatment, and prevention.


Subject(s)
Hydrocephalus , Thromboembolism , Thrombosis , Cerebrospinal Fluid Shunts/adverse effects , Humans , Hydrocephalus/complications , Hydrocephalus/surgery , Thrombosis/etiology , Ventriculoperitoneal Shunt/adverse effects , Ventriculoperitoneal Shunt/methods
20.
Opt Lett ; 46(24): 6112-6115, 2021 Dec 15.
Article in English | MEDLINE | ID: mdl-34913930

ABSTRACT

Multicore fibers (MCFs) offer a fascinating solution to the need to increase the fiber density and thus meet the exponentially growing demand for capacity in optical communication networks. Despite overwhelming research into MCFs, the desire for a general fusion splicing scheme between dissimilar MCFs remains unanswered. Here, we propose a tapering technique to reshape MCFs that includes both reverse-tapering and down-tapering schemes and can be exploited to tailor the core-to-core spacing and modify the modal property of MCFs. By matching both the spacing and the mode field diameter, we demonstrated a low-loss (0.18 ± 0.10 dB) and low-crosstalk (-68 ± 3 dB) fusion splice between two spacing-mismatched MCFs with a spacing difference of up to 26 µm. The proposed novel schemes are also suitable for splicing between MCFs with slightly different spacings and can provide a unique perspective for fabricating MCF devices and boosting various MCF applications.

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