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1.
Cell ; 152(5): 1077-90, 2013 Feb 28.
Article in English | MEDLINE | ID: mdl-23434321

ABSTRACT

Malignant peripheral nerve sheath tumors (MPNSTs) are soft tissue sarcomas that arise in connective tissue surrounding peripheral nerves. They occur sporadically in a subset of patients with neurofibromatosis type 1 (NF1). MPNSTs are highly aggressive, therapeutically resistant, and typically fatal. Using comparative transcriptome analysis, we identified CXCR4, a G-protein-coupled receptor, as highly expressed in mouse models of NF1-deficient MPNSTs, but not in nontransformed precursor cells. The chemokine receptor CXCR4 and its ligand, CXCL12, promote MPNST growth by stimulating cyclin D1 expression and cell-cycle progression through PI3-kinase (PI3K) and ß-catenin signaling. Suppression of CXCR4 activity either by shRNA or pharmacological inhibition decreases MPNST cell growth in culture and inhibits tumorigenesis in allografts and in spontaneous genetic mouse models of MPNST. We further demonstrate conservation of these activated molecular pathways in human MPNSTs. Our findings indicate a role for CXCR4 in NF1-associated MPNST development and identify a therapeutic target.


Subject(s)
Autocrine Communication , Chemokine CXCL12/metabolism , Nerve Sheath Neoplasms/metabolism , Nerve Sheath Neoplasms/pathology , Receptors, CXCR4/metabolism , Cell Cycle , Cell Proliferation , Cell Transformation, Neoplastic , Cells, Cultured , Gene Knockdown Techniques , Humans , Neurofibromatosis 1/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction
2.
Mol Cell ; 80(2): 296-310.e6, 2020 10 15.
Article in English | MEDLINE | ID: mdl-32979304

ABSTRACT

Necroptosis induction in vitro often requires caspase-8 (Casp8) inhibition by zVAD because pro-Casp8 cleaves RIP1 to disintegrate the necrosome. It has been unclear how the Casp8 blockade of necroptosis is eliminated naturally. Here, we show that pro-Casp8 within the necrosome can be inactivated by phosphorylation at Thr265 (pC8T265). pC8T265 occurs in vitro in various necroptotic cells and in the cecum of TNF-treated mice. p90 RSK is the kinase of pro-Casp8. It is activated by a mechanism that does not need ERK but PDK1, which is recruited to the RIP1-RIP3-MLKL-containing necrosome. Phosphorylation of pro-Casp8 at Thr265 can substitute for zVAD to permit necroptosis in vitro. pC8T265 mimic T265E knockin mice are embryonic lethal due to unconstrained necroptosis, and the pharmaceutical inhibition of RSK-mediated pC8T265 diminishes TNF-induced cecum damage and lethality in mice by halting necroptosis. Thus, phosphorylation of pro-Casp8 at Thr265 by RSK is an intrinsic mechanism for passing the Casp8 checkpoint of necroptosis.


Subject(s)
3-Phosphoinositide-Dependent Protein Kinases/metabolism , Caspase 8/metabolism , Necroptosis , Ribosomal Protein S6 Kinases, 90-kDa/metabolism , Signal Transduction , Animals , Cecum/injuries , Cecum/pathology , Cell Line , Embryo, Mammalian/metabolism , Embryonic Development/drug effects , Extracellular Signal-Regulated MAP Kinases/metabolism , Humans , Mice, Inbred C57BL , Mutation/genetics , Necroptosis/drug effects , Organ Specificity , Phosphorylation/drug effects , Phosphothreonine/metabolism , Protein Kinases/metabolism , Ribosomal Protein S6 Kinases, 90-kDa/antagonists & inhibitors , Signal Transduction/drug effects , Tumor Necrosis Factor-alpha/pharmacology
3.
Nature ; 580(7803): 386-390, 2020 04.
Article in English | MEDLINE | ID: mdl-32296174

ABSTRACT

The aetiology of inflammatory bowel disease (IBD) is a multifactorial interplay between heredity and environment1,2. Here we report that deficiency in SETDB1, a histone methyltransferase that mediates the trimethylation of histone H3 at lysine 9, participates in the pathogenesis of IBD. We found that levels of SETDB1 are decreased in patients with IBD, and that mice with reduced SETDB1 in intestinal stem cells developed spontaneous terminal ileitis and colitis. SETDB1 safeguards genome stability3, and the loss of SETDB1 in intestinal stem cells released repression of endogenous retroviruses (retrovirus-like elements with long repeats that, in humans, comprise approximately 8% of the genome). Excessive viral mimicry generated by motivated endogenous retroviruses triggered Z-DNA-binding protein 1 (ZBP1)-dependent necroptosis, which irreversibly disrupted homeostasis of the epithelial barrier and promoted bowel inflammation. Genome instability, reactive endogenous retroviruses, upregulation of ZBP1 and necroptosis were all seen in patients with IBD. Pharmaceutical inhibition of RIP3 showed a curative effect in SETDB1-deficient mice, which suggests that targeting necroptosis of intestinal stem cells may represent an approach for the treatment of severe IBD.


Subject(s)
Genomic Instability , Histone-Lysine N-Methyltransferase/metabolism , Inflammatory Bowel Diseases/metabolism , Necroptosis , Stem Cells/metabolism , Animals , Histone-Lysine N-Methyltransferase/genetics , Humans , Inflammatory Bowel Diseases/genetics , Inflammatory Bowel Diseases/pathology , Mice , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism , Stem Cells/cytology
4.
Phys Chem Chem Phys ; 26(14): 10633-10640, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38511282

ABSTRACT

A dual-functional switchable metamaterial absorber (MMA) based on vanadium dioxide (VO2), which achieves flexible switching between broadband absorption and four-band absorption by adjusting the VO2 conductivity, was proposed. The device has a broadband absorption function when VO2 is in the metal phase, and the conductivity is 3 × 105 S m-1. Numerical simulation shows that the absorption rate of the device reaches over 90% in the frequency range of 3.36-6.98 THz. The absorber exhibits polarization insensitivity and wide-angle absorption to transverse electric (TE) and transverse magnetic (TM) waves. When VO2 is in the insulator phase, and the conductivity is 3 × 102 S m-1, the device switches to a narrowband absorber with a band-efficient absorption function. Numerical simulation shows that the device has an absorption rate of 99.7% at 2.39 THz, 98.3% at 2.83 THz, 95.6% at 3.84 THz, and 96.1% at 4.61 THz. It can be used as a sensor with high sensitivity. In addition, to verify the absorption mechanism of the absorber, we introduced impedance matching theory to analyze the device. Finally, the influence of structural parameters on the performance of resonators was investigated. Through the joint action of multi-layer structures, the proposed MMA concentrates broadband and narrowband absorption functions on one device, achieving flexible switching between tasks without changing the structure. The switchable metamaterial absorber designed through simple tuning methods has broad application prospects in stealth technology and thermal emitters. It provides a wide range of ideas for the design of terahertz functional devices.

5.
Anesth Analg ; 138(2): 456-464, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-37874765

ABSTRACT

BACKGROUND: Hypoxia often occurs due to shared airway and anesthetic sedation-induced hypoventilation in patients receiving flexible bronchoscopy (FB) under deep sedation. Previous evidence has shown that supraglottic jet oxygenation and ventilation (SJOV) via Wei nasal jet tube (WNJ) reduces the incidence of hypoxia during FB. This study aimed to investigate the extent to which SJOV via WNJ could decrease the incidence of hypoxia in patients under deep sedation as compared to oxygen supplementation via WNJ alone or nasal catheter (NC) for oxygen supplementation during FB. METHODS: This was a single-center 3-arm randomized controlled trial (RCT). Adult patients scheduled to undergo FB were randomly assigned to 3 groups: NC (oxygen supplementation via NC), low-pressure low-flow (LPLF) (low-pressure oxygen supplementation via WNJ alone), or SJOV (high-pressure oxygen supplementation via WNJ). The primary outcome was hypoxia (defined as peripheral saturation of oxygen [Sp o2 ] <90% lasting more than 5 seconds) during FB. Secondary outcomes included subclinical respiratory depression or severe hypoxia, and rescue interventions specifically performed for hypoxia treatment. Other evaluated outcomes were sore throat, xerostomia, nasal bleeding, and SJOV-related barotraumatic events. RESULTS: One hundred and thirty-two randomized patients were included in 3 interventions (n = 44 in each), and all were included in the final analysis under intention to treat. Hypoxia occurred in 4 of 44 patients (9.1%) allocated to SJOV, compared to 38 of 44 patients (86%) allocated to NC, with a relative risk (RR) for hypoxia, 0.11; 98% confidence interval (CI), 0.02-0.51; P < .001; or to 27 of 44 patients (61%) allocated to LPLF, with RR for hypoxia, 0.15; 95% CI, 0.04-0.61; P < .001, respectively. The percentage of subclinical respiratory depression was also significantly diminished in patients with SJOV (39%) compared with patients with NC (100%) or patients with LPLF (96%), both P < .001. In SJOV, no severe hypoxia event occurred. More remedial interventions for hypoxia were needed in the patients with NC. Higher risk of xerostomia was observed in patients with SJOV. No severe adverse event was observed throughout the study. CONCLUSIONS: SJOV via WNJ effectively reduces the incidence of hypoxia during FB under deep sedation.


Subject(s)
Deep Sedation , Respiratory Insufficiency , Xerostomia , Adult , Humans , Bronchoscopy/adverse effects , Deep Sedation/adverse effects , Hypoxia/diagnosis , Hypoxia/etiology , Hypoxia/prevention & control , Oxygen , Xerostomia/complications
6.
Appl Opt ; 63(9): 2148-2155, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38568566

ABSTRACT

A metalens is a flat lens that can control the phase of light so that dispersed light can be reconcentrated. This study devised a tunable metalens with a switchable focal length based on the phase transition properties of vanadium dioxide (V O 2). The unit structure comprises three layers from bottom to top: gold, polyimide, and two square resonant rings. The metalens can not only transform incident x-polarized waves into y-polarized waves but also achieve beam focusing simultaneously. The designed metalens achieves polarization conversion efficiency at an operating frequency of 0.8 THz. In the insulating state of V O 2, the beam focal point is at L=1914µm; in the metallic state, the wave converges at L=982µm, closely aligning with the predetermined focal length. By controlling external temperature, focal point switching can be achieved, making it highly versatile in practical applications.

7.
Eur Arch Otorhinolaryngol ; 281(4): 1659-1670, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38189965

ABSTRACT

PURPOSE: Clinical presentations encompass respiratory, feeding issues, nasopharyngeal mass, meningitis, CSF leakage, craniofacial anomalies, and endocrine problems. Surgery is the primary treatment, transitioning from frontal craniotomy to endoscopic methods, offering improved outcomes. Yet, more studies are needed. A comprehensive review on trans-sellar trans-sphenoidal encephalocele (TSTSE) is missing. Our study aims to fill this gap, offering a comprehensive perspective for physicians. METHODS: This review adhered to the PRISMA guideline. Eligible studies focused on human subjects, specifically trans-sellar encephaloceles, and provided comprehensive treatment details. English language articles published up to April 11th, 2023, were considered. Two trained researchers conducted article screening using consistent criteria. Data extraction covered various aspects, including clinical presentation, surgical methods, and outcomes, with results presented descriptively in two tables. Due to the rarity of this congenital anomaly, meta-analysis and publication bias assessment were not feasible. Data extraction was independently conducted by two reviewers, with subsequent cross-verification. RESULTS: A total of 36 patients were identified from 14 studies, the most frequently observed clinical presentation was dyspnea (41.67%) and the most frequently observed accompanying anomaly was cleft lip/palate (55.56%). CT and MRI were adopted in nearly all the cases, and trans-nasal approach was the most often used surgical approach (57.14%) with the 'soft material combination' the most commonly used method for cranial base repairment (35.71%). A total of two deaths occurred and diabetes insipidus was the most common perioperative complication which occurred in six surgery patients (21.43%). CONCLUSION: TSTSE predominantly affects males and presents with dyspnea, visual deficits, pituitary insufficiency, and cranial base-related symptoms. Early diagnosis is critical, with advanced imaging playing a key role. Endocrine assessment is vital for hormone management. Surgery offers symptom relief but entails risks, including reported fatalities and complications. The choice between surgery and conservative management requires careful deliberation. The trans-nasal approach is favored for its reduced trauma, yet further research is necessary to validate this preference.


Subject(s)
Encephalocele , Humans , Encephalocele/surgery , Encephalocele/diagnosis , Prognosis , Sella Turcica/surgery , Sella Turcica/diagnostic imaging , Sphenoid Bone/surgery
8.
Bioorg Med Chem ; 94: 117478, 2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37742398

ABSTRACT

A series of pentacyclic triterpene-amino acid derivatives were synthesized and tested for anti-proliferative activity. The results showed that most of the target compounds had good anti-proliferative activity. 2c did not contain protecting groups and hydrochloride, had excellent cytotoxicity, so it had been selected for further study in the mechanism of action in T24 cells. The data from transcriptome sequencing indicated that 2c was found to be closely related to apoptosis and autophagy. Observation of fluorescence staining and analysis from flow cytometry demonstrated that 2c induced apoptosis and cause cell cycle arrest in S/G2 phase in T24 cells. Molecular mechanism studies exhibited that 2c induced apoptosis in the intrinsic and extrinsic pathways. 2c also induced cellular autophagy in T24 cells. Results from Western Blotting showed that 2c could activate JNK pathway and inhibit PI3K/AKT/mTOR pathway. In conclusion, 2c was deserved further investigation in the field of anti-tumor.

9.
Tohoku J Exp Med ; 261(2): 109-116, 2023 Oct 07.
Article in English | MEDLINE | ID: mdl-37407440

ABSTRACT

This study aimed to identify the risk factors associated with puncture site bleeding following percutaneous puncture of the common femoral artery during interventional treatment of cerebrovascular disease (CVD). A retrospective analysis was conducted on 710 patients who underwent interventional treatment for CVD via femoral artery puncture. Among them, 26 individuals (3.66%) experienced bleeding at the femoral artery puncture site. Binary logistic regression analysis was performed to identify risk factors for puncture site bleeding. The impact of salt bag compression on postoperative bleeding was evaluated in patients with intermediate to high bleeding risk scores. The bleeding group showed higher blood pressure, lower platelet counts, longer prothrombin time and activated partial thromboplastin time, as well as a higher prevalence of larger vascular sheath sizes and variations in the timing of anti-coagulant and anti-platelet therapy administration. The bleeding risk score was higher in the bleeding group, indicating its predictive value for bleeding risk. Higher bleeding risk score, unstable blood pressure, repeated puncture, and serious vascular conditions were significant risk factors for puncture site bleeding. Application of salt bag compression for a duration of 2 hours reduced postoperative puncture site bleeding in patients with intermediate to high bleeding risk scores. Our study identified several significant risk factors for puncture site bleeding after cerebral vascular intervention via femoral artery puncture, including the bleeding risk score, blood pressure, repeated puncture, and vascular conditions. Implementing salt bag compression as a preventive measure can help mitigate bleeding complications in these high-risk patients.


Subject(s)
Cardiovascular Diseases , Cerebrovascular Disorders , Humans , Femoral Artery/surgery , Retrospective Studies , Treatment Outcome , Hemorrhage , Punctures/adverse effects , Risk Factors , Cerebrovascular Disorders/complications , Cardiovascular Diseases/complications
10.
BMC Med Educ ; 23(1): 34, 2023 Jan 17.
Article in English | MEDLINE | ID: mdl-36650532

ABSTRACT

OBJECTIVE: To investigate the influence of group counselling on the career planning and career maturity of male nursing students. METHOD: Sixty male nursing students were randomly selected from a specific-level first-class hospital in Hunan Province from July to August 2020 by using the convenience sampling method and were subsequently divided into the control group and the experimental group using the random number table method. The control group received routine pre-job training, including aspects concerning the hospital profile, nurse etiquette, nursing core systems, professional ethics, nursing emergency treatment and career prospects and planning. In the experimental group, career planning group counselling was added after the regular pre-service training (once a week) with each session lasting 2 h for a total of six training sessions. At six weeks and three months after the intervention, the career status evaluation scale and the college students' career maturity scale were used to compare the career planning and career maturity status of the two groups of male nursing students. RESULTS: After six weeks and three months of intervention, all the dimensions and total scores of both the career status evaluation scale and the career maturity scale in the experimental group were superior to those in the control group with statistically significant differences (all P < 0.05). The repeated measures of variance analysis indicated that the differences in the total score for career planning and the four dimensions in terms of intergroup effect, time effect and interaction effect between the two groups were statistically significant (P < 0.05). The intergroup effect, time effect and interaction effect of the total score for vocational maturity, career goal, career confidence, career value, career freedom and career reference of the two groups were statistically significant (P < 0.05), while the time effect of the relative dependency dimension was also statistically significant (P < 0.05). CONCLUSION: Group counselling can significantly improve the career planning and career maturity status of male nursing students and has a certain long-term effect.


Subject(s)
Career Choice , Counseling , Education, Nursing, Baccalaureate , Students, Nursing , Humans , Male , Students, Nursing/psychology
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