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4.
Adv Sci (Weinh) ; 11(7): e2308171, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38072663

RESUMO

Achieving hemostasis effectively is essential for surgical success and excellent patient outcomes. However, it is challenging to develop hemostatic adhesives that are fast-acting, strongly adherent, long-lasting, and biocompatible for treating hemorrhage. In this study, a sequential crosslinking fibrin glue (SCFG) is developed, of which the first network of the fibrin glue forms in situ within 2 s to act as an initial physical barrier and locks the gelatin methacryloyl precursor for tight construction of the second network to enhance wet adhesion and durability for tissues covered with blood. The sequential crosslinking glue can provide large pressures (≈280 mmHg of burst pressure), makes strong (38 kPa of shear strength) and tough (≈60 J m-2 of interfacial toughness) interfaces with wet tissues, and outperforms commercial hemostatic agents and gelatin methacryloyl. SCFG are demonstrated as an effective and safe sealant to enhance the treatment outcomes of bleeding tissues in rat, rabbit, and pig models. The ultrafast gelation, strong adhesion and durability, excellent compatibility, and easy manufacture of SCFG make it a promising hemostatic adhesive for clinical applications.


Assuntos
Adesivo Tecidual de Fibrina , Hemostáticos , Humanos , Ratos , Suínos , Animais , Coelhos , Adesivo Tecidual de Fibrina/uso terapêutico , Hemostáticos/uso terapêutico , Hemostasia , Adesivos
5.
Medicine (Baltimore) ; 102(43): e35684, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37904447

RESUMO

At present, detailed demographic and clinical data of moyamoya disease (MMD) in the population of Southeast China are lacking. Therefore, this study aimed to evaluate the epidemiological and clinical features of MMD in Southeast China. Our cohort included 170 patients diagnosed with MMD over the preceding 5 years. Clinical characteristics were obtained through a retrospective chart review, while follow-up information and outcomes were obtained through clinical visits and imaging. The median age at symptom onset was 49 years (range 4-73), with a peak in the age distribution observed at 41 to 60 years. The female-to-male ratio was 1.125 (90/80), and the ratio of the ischemic type to the hemorrhagic type was 2.33 (119/50). The most common initial symptom was an ischemic event. The 5-year Kaplan-Meier risk of stroke was 4.9% for all patients treated with surgical revascularization. Of all patients, 83.9% were able to live independently with no significant disability, and 89.8% showed improved cerebral hemodynamics. Our study provided detailed demographic and clinical data on Southeastern Chinese patients with MMD, which was consistent with findings in other parts of China. Raising clinical awareness of MMD in primary hospitals is important to facilitate early diagnosis and timely treatment of MMD patients.


Assuntos
Revascularização Cerebral , Doença de Moyamoya , Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Doença de Moyamoya/diagnóstico , Doença de Moyamoya/epidemiologia , Doença de Moyamoya/cirurgia , Resultado do Tratamento , China/epidemiologia , Revascularização Cerebral/métodos
6.
Chin J Integr Med ; 29(10): 885-894, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37357242

RESUMO

OBJECTIVE: To explore the effect and mechanism of schisandrin B (Sch B) in the treatment of cerebral ischemia in rats. METHODS: The cerebral ischemia models were induced by middle cerebral artery occlusion (MCAO) and reperfusion. Sprague-Dawley rats were divided into 6 groups using a random number table, including sham, MCAO, MCAO+Sch B (50 mg/kg), MCAO+Sch B (100 mg/kg), MCAO+Sch B (100 mg/kg)+LY294002, and MCAO+Sch B (100 mg/kg)+wortmannin groups. The effects of Sch B on pathological indicators, including neurological deficit scores, cerebral infarct volume, and brain edema, were subsequently studied. Tissue apoptosis was identified by terminal transferase-mediated dUTP nick end-labeling (TUNEL) staining. The protein expressions involved in apoptosis, inflammation response and oxidative stress were examined by immunofluorescent staining, biochemical analysis and Western blot analysis, respectively. The effect of Sch B on phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling was also explored. RESULTS: Sch B treatment decreased neurological deficit scores, cerebral water content, and infarct volume in MCAO rats (P<0.05 or P<0.01). Neuronal nuclei and TUNEL staining indicated that Sch B also reduced apoptosis in brain tissues, as well as the Bax/Bcl-2 ratio and caspase-3 expression (P<0.01). Sch B regulated the production of myeloperoxidase, malondialdehyde, nitric oxide and superoxide dismutase, as well as the release of cytokine interleukin (IL)-1 ß and IL-18, in MCAO rats (P<0.05 or P<0.01). Sch B promoted the phosphorylation of PI3K and AKT. Blocking the PI3K/AKT signaling pathway with LY294002 or wortmannin reduced the protective effect of Sch B against cerebral ischemia (P<0.05 or P<0.01). CONCLUSIONS: Sch B reduced apoptosis, inflammatory response, and oxidative stress of MCAO rats by modulating the PI3K/AKT pathway. Sch B had a potential for treating cerebral ischemia.

7.
Neuropharmacology ; 237: 109603, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37236529

RESUMO

Liraglutide has been recently discovered to penetrate the blood-brain barrier to exert neuroprotective effects. However, relevant mechanisms of the protective effects of liraglutide on ischaemic stroke remain to be elucidated. This study examined the mechanism of GLP-1R in regulating the protective effect of liraglutide against ischaemic stroke. Middle cerebral artery occlusion (MCAO) male Sprague-Dawley rat model with/without GLP-1R or Nrf2 knockdown was established and subjected to liraglutide treatment. Then neurological deficit and brain oedema of rats was evaluated and brain tissues were subjected to TTC, Nissl, TUNEL and immunofluorescence staining. Rat primary microglial cells firstly underwent lipopolysaccharide (LPS) treatment, then GLP-1R or Nrf2 knockdown treatment, and finally Liraglutide treatment to research the NLRP3 activation. As a result, Liraglutide protected rats' brain tissues after MCAO, which attenuated brain oedema, infarct volume, neurological deficit score, neuronal apoptosis and Iba1 expression but enhanced live neurons. However, GLP-1R knockdown abrogated these protective effects of liraglutide on MCAO rats. According to in vitro experiments, Liraglutide promoted M2 polarisation, activated Nrf2 and inhibited NLRP3 activation in LPS-induced microglial cells, but GLP-1R or Nrf2 knockdown reversed these effects of Liraglutide on LPS-induced microglial cells. Further, Nrf2 knockdown counteracted the protection of liraglutide on MCAO rats, whereas sulforaphane (agonist of Nrf2) counteracted the effect of Nrf2 knockdown on liraglutide-treated MCAO rats. Collectively, GLP-1R knockdown abrogated the protection of liraglutide on MCAO rats by activating NLRP3 via inactivating Nrf2.


Assuntos
Edema Encefálico , Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Ratos , Animais , Liraglutida/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Edema Encefálico/tratamento farmacológico , Lipopolissacarídeos/farmacologia , Ratos Sprague-Dawley , Acidente Vascular Cerebral/tratamento farmacológico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo
8.
Neurosurg Rev ; 46(1): 64, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36877325

RESUMO

To explore the utility of transcranial Doppler (TCD) findings when assessing bypass patency in patients with Moyamoya disease (MMD). Computed tomography angiography (CTA) and TCD sonography (TCDS) were performed before and after surgery to evaluate bypass patency. The peak systolic flow velocity (PSV) of the superficial temporal artery (STA) and the pulsatility index (PI) were compared between the groups that achieved patency and not, and receiver operating characteristic (ROC) curve analyses were used to define the TCDS criteria revealing patency. This study included 35 hemispheres (15 women; mean age 47 years) with Moyamoya disease who underwent STA-middle carotid artery bypass in our institution between January 2022 and October 2022. The PSV first increased on postoperative days 4-5 and then decreased on postoperative days 6-7 and 7-8. Patients with transient neurological diseases (TNDs), compared to those without, evidenced a significantly lower PSV value (P < 0.05). Compared with the non-patency group, the PSV was higher (P < 0.001) in the patency group. The cutoff values reflecting patency with good sensitivity and specificity were PSV > 49.00; PSV ratio (postoperative/preoperative) > 1.218; PSV ratio (operation side/contralateral side) > 1.082; and PSV ratio (adjusted) > 1.202. In the patency group, the PSV and PI significantly increased (P < 0.001) and decreased (P < 0.001) respectively. Bypass patency can be noninvasively and accurately evaluated via TCDS, affording an objective basis for assessment of the effect of revascularization surgery on patients with MMD.


Assuntos
Angiografia por Tomografia Computadorizada , Doença de Moyamoya , Humanos , Feminino , Pessoa de Meia-Idade , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Ultrassonografia Doppler Transcraniana , Angiografia
9.
Small ; 18(52): e2204951, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36333122

RESUMO

Photodynamic therapy (PDT) has been showing great potential in cancer treatment. However, the efficacy of PDT is always limited by the intrinsic hypoxic tumor microenvironment (TME) and the low accumulation efficiency of photosensitizers in tumors. To address the issue, a multifunctional hollow multilayer nanoplatform (H-MnO2 @TPyP@Bro) comprising manganese dioxide, porphyrin (TPyP) and bromelain (Bro), is developed for enhanced photodynamic therapy. MnO2 catalyzes the intracellular hydrogen peroxide (H2 O2 ) to produce oxygen (O2 ), reversing the hypoxic TME in vivo. The generated O2 is converted into singlet oxygen (1 O2 ) by the TPyP shell under near-infrared light, which can inhibit tumor proliferation. Meanwhile, the Bro can digest collagen in the extracellular matrix around the tumor, and can promote the accumulation of H-MnO2 @TPyP@Bro in the deeper tumor tissue, further improving the therapeutic effect of PDT. In addition, MnO2 can react with the overexpressed glutathione in TME to release Mn2+ . Consequently, Mn2+ not only induces chemo-dynamic therapy based on Fenton reaction by converting H2 O2 into hydroxyl radicals, but also activates the Mn2+ -based magnetic resonance imaging. Therefore, the developed H-MnO2 @TPyP@Bro nanoplatform can effectively modulate the unfavorable TME and overcome the limitations of conventional PDT for cancer diagnostic and therapeutic.


Assuntos
Neoplasias , Fotoquimioterapia , Porfirinas , Humanos , Fotoquimioterapia/métodos , Compostos de Manganês , Porfirinas/farmacologia , Porfirinas/uso terapêutico , Bromelaínas/farmacologia , Bromelaínas/uso terapêutico , Óxidos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Oxigênio/farmacologia , Neoplasias/terapia , Peróxido de Hidrogênio/farmacologia , Microambiente Tumoral
10.
Opt Lett ; 47(17): 4584-4587, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36048710

RESUMO

Bridging multi-mode fibers and Mamyshev regenerators holds promise for pulse energy scaling in fiber lasers. However, initialization of a multi-mode Mamyshev oscillator remains a practical challenge. Here we report self-starting spatiotemporal mode-locking (STML) in a multi-mode Mamyshev oscillator without active assistance. The first initialized mode-locking is unstable, but stable STML can be attained by increasing the filter separation. Simulations verify the capability of reaching self-starting STML using Mamyshev regenerators and unveil the effect of filter separation on the self-starting ability.

11.
Chin J Integr Med ; 28(7): 594-602, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35015222

RESUMO

OBJECTIVE: To determine whether Schisandrin B (Sch B) attenuates early brain injury (EBI) in rats with subarachnoid hemorrhage (SAH). METHODS: Sprague-Dawley rats were divided into sham (sham operation), SAH, SAH+vehicle, and SAH+Sch B groups using a random number table. Rats underwent SAH by endovascular perforation and received Sch B (100 mg/kg) or normal saline after 2 and 12 h of SAH. SAH grading, neurological scores, brain water content, Evan's blue extravasation, and terminal transferase-mediated dUTP nick end-labeling (TUNEL) staining were carried out 24 h after SAH. Immunofluorescent staining was performed to detect the expressions of ionized calcium binding adapter molecule 1 (Iba-1) and myeloperoxidase (MPO) in the rat brain, while the expressions of B-cell lymphoma 2 (Bcl-2), Bax, Caspase-3, nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3), apoptosis-associated specklike protein containing the caspase-1 activator domain (ASC), Caspase-1, interleukin (IL)-1ß, and IL-18 in the rat brains were detected by Western blot. RESULTS: Compared with the SAH group, Sch B significantly improved the neurological function, reduced brain water content, Evan's blue content, and apoptotic cells number in the brain of rats (P<0.05 or P<0.01). Moreover, Sch B decreased SAH-induced expressions of Iba-1 and MPO (P<0.01). SAH caused the elevated expressions of Bax, Caspase-3, NLRP3, ASC, Caspase-1, IL-1ß, and IL-18 in the rat brain (P<0.01), all of which were inhibited by Sch B (P<0.01). In addition, Sch B increased the Bcl-2 expression (P<0.01). CONCLUSION: Sch B attenuated SAH-induced EBI, which might be associated with the inhibition of neuroinflammation, neuronal apoptosis, and the NLRP3 inflammatory signaling pathway.


Assuntos
Lesões Encefálicas , Hemorragia Subaracnóidea , Animais , Apoptose , Encéfalo/patologia , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/patologia , Caspase 3/metabolismo , Ciclo-Octanos , Azul Evans , Inflamassomos/metabolismo , Interleucina-18/metabolismo , Lignanas , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Compostos Policíclicos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/tratamento farmacológico , Água , Proteína X Associada a bcl-2/metabolismo
12.
FASEB J ; 36(1): e22075, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34919285

RESUMO

Long non-coding RNAs (lncRNAs) regulate neurological damage in cerebral ischemia-reperfusion injury (CIRI). This study aimed to investigate the biological roles of lncRNA CEBPA-AS1 in CIRI. Middle cerebral artery occlusion and ischemia-reperfusion injury (MCAO/IR) rat model and oxygen-glucose deprivation and reoxygenation (OGD/R) cell lines were generated; the expression of CEBPA-AS1 was evaluated by qRT-PCR. The effects of CEBPA-AS1 on cell apoptosis and nerve damage were examined. The downstream microRNA (miRNA) and mRNA of CEBPA-AS1 were predicted and verified. We found that overexpression of CEBPA-AS1 could attenuate MCAO/IR-induced nerve damage and neuronal apoptosis in the rat model. Knockdown of CEBPA-AS1 aggravated cell apoptosis and enhanced the production of LDH and MDA in the OGD/R cells. Upon examining the molecular mechanisms, we found that CEBPA-AS1 stimulated APPL1 expression by combining with miR-340-5p, thereby regulating the APPL1/LKB1/AMPK pathway. In the rescue experiments, CEBPA-AS1 overexpression was found to attenuate OGD/R-induced cell apoptosis and MCAO/IR induced nerve damage, while miR-340-5p reversed these effects of CEBPA-AS1. In conclusion, CEBPA-AS1 could decrease CIRI by sponging miR-340-5, regulating the APPL1/LKB1/AMPK pathway.


Assuntos
Quinases Proteína-Quinases Ativadas por AMP/biossíntese , Proteínas Quinases Ativadas por AMP/biossíntese , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Transtornos Cerebrovasculares/metabolismo , MicroRNAs/biossíntese , Proteínas do Tecido Nervoso/biossíntese , RNA Longo não Codificante/biossíntese , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais , Quinases Proteína-Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Apoptose , Transtornos Cerebrovasculares/genética , Transtornos Cerebrovasculares/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica , MicroRNAs/genética , Proteínas do Tecido Nervoso/genética , RNA Longo não Codificante/genética , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia
13.
Materials (Basel) ; 14(12)2021 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-34199204

RESUMO

With the increase of cement output, the demand for cement expansion agents increases, and composite expansion agents have become the development trend. The purpose of this study is to study the microscopic change process and expansion effect of calcium oxide and magnesium oxide double expansion agents. After calcination at different temperatures, the change process of microscopic morphology of calcined products was observed. Through calcining dolomite at 900 °C, the mixture D900 of calcium oxide and magnesium oxide was obtained. To prepare mixed cement, 10 wt %, 20 wt %, and 30 wt % of D900 were added into cement to prepare mixed cement. At the same time, the compressive strength, deformation, and porosity of mixed cement were measured. The results show that adding D900 improves the expansion rate of early cement paste and reduces the compressive strength. After 120 days, the compressive strength of 20 wt % cement paste is higher than that of blank cement paste, and the porosity of 20 wt % cement paste is the lowest among the three mixed cements. This shows that 20 wt % is a more suitable substitute.

14.
Phys Rev Lett ; 126(9): 093901, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33750164

RESUMO

Dissipative nonlinear wave dynamics have been investigated extensively in mode-locked lasers with single transverse mode, whereas there are few studies related to three-dimensional nonlinear dynamics within lasers. Recently, spatiotemporal mode locking (STML) was proposed in lasers with small modal (i.e., transverse-mode) dispersion, which has been considered to be critical for achieving STML in those cavities because the small dispersion can be easily balanced. Here, we demonstrate that STML can also be achieved in multimode lasers with much larger modal dispersion, where we find that the intracavity saturable absorber plays an important role for counteracting the large modal dispersion. Furthermore, we observe a new STML phenomenon of passive nonlinear autoselection of single-mode mode locking, resulting from the interaction between spatiotemporal saturable absorption and spatial gain competition. Our work significantly broadens the design possibilities for useful STML lasers thus making them much more accessible for applications, and extends the explorable parameter space of the novel dissipative spatiotemporal nonlinear dynamics that can be achieved in these lasers.

15.
Opt Express ; 27(8): 11435-11446, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31052987

RESUMO

Experimental observations of spatiotemporal mode-locked multiple-soliton, including harmonic mode locking and multiple pulses, in multimode fiber (MMF) lasers are reported. Numerical simulations are conducted to investigate the nonlinear dynamics of multi-pulsing. The influences of cavity parameters on the spatiotemporal outputs are analyzed by simulations, which agree with the experimental observations qualitatively. This work would contribute to understanding the complex spatiotemporal nonlinear dynamics in MMF lasers.

16.
Opt Express ; 26(13): 16147-16154, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30119451

RESUMO

We demonstrate a novel and compact FBG interrogation system for multiplexed static strain sensing with a free running mode-locked fiber laser. Multiplexed FBG array in cascading are interrogated by coherent dual-comb pulses generated from a single fiber laser. Dual-comb spectroscopy is achieved with the fiber laser to precisely detect the strain-induced spectral shifts of the FBG sensors. Multi-point strain measurements are performed to characterize the proposed system, where a large dynamic range of 520 µÎµ with 0.5 µÎµ resolution is achieved.

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