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1.
Small ; : e2403600, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949410

RESUMO

BiVO4-based photoanode is one of the most promising photoanodes for photoelectrocatalytic water splitting. However, the serious problem of interface charge recombination limits its further development. Here, a Mo:BiVO4/NiOx/CPF-TCzB/NiCoBi photoanode is constructed with double hole transport layer and an energy level gradient to achieve an effective photo-generated holes extraction and accumulation at the surface electrocatalyst. The conjugated polycarbazole framework CPF-TCzB is used as hole transport layer to eliminate the charge recombination center between Mo:BiVO4 and NiCoBi electrocatalyst and realize the extraction and storage of photo-generated hole; NiOx nanoparticles are further inserted between Mo:BiVO4 and CPF-TCzB to form a gradient energy level, eliminating the energy level barrier and optimizing band alignment. As a result, Mo:BiVO4/NiOx/CPF-TCzB/NiCoBi achieves a much higher photocurrent densities of 3.14 mA cm-2 than that of Mo:BiVO4 (0.42 mA cm-2) at 0.6 V versus RHE. This work provides an specific way to adjust the band structure of BiVO4-based photoanodes and realize efficient hole extraction and storage for PEC water splitting.

2.
Clin Interv Aging ; 19: 981-991, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827237

RESUMO

Background: Dexmedetomidine (Dex) may have anti-inflammatory properties and potentially reduce the incidence of postoperative organ injury. Objective: To investigate whether Dex protects pulmonary and renal function via its anti-inflammatory effects in elderly patients undergoing prolonged major hepatobiliary and pancreatic surgery. Design and Setting: Between October 2019 and December 2020, this randomized controlled trial was carried out at a tertiary hospital in Chongqing, China. Patients: 86 patients aged 60-75 who underwent long-duration (> 4 hrs) hepatobiliary and pancreatic surgery without significant comorbidities were enrolled and randomly assigned into two groups at a 1:1 ratio. Interventions: Patients were given either Dex or an equivalent volume of 0.9% saline (Placebo) with a loading dose of 1 µg kg-1 for 10 min, followed by 0.5 µg kg-1 hr-1 for maintenance until the end of surgery. Main Outcome Measures: The changes in serum concentrations of interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) were primary outcomes. Results: At one hour postoperatively, serum IL-6 displayed a nine-fold increase (P<0.05) in the Placebo group. Administration of Dex decreased IL-6 to 278.09 ± 45.43 pg/mL (95% CI: 187.75 to 368.43) compared to the Placebo group (P=0.019; 432.16 ± 45.43 pg/mL, 95% CI: 341.82 to 522.50). However, no significant differences in TNF-α were observed between the two groups. The incidence of postoperative acute kidney injury was twice as high in the Placebo group (9.30%) compared to the Dex group (4.65%), and the incidence of postoperative acute lung injury was 23.26% in the Dex group, lower than that in the Placebo group (30.23%), although there was no statistical significance between the two groups. Conclusion: Dex administration in elderly patients undergoing major hepatobiliary and pancreatic surgery reduces inflammation and potentially protects kidneys and lungs. Registration: Chinese Clinical Trials Registry, identifier: ChiCTR1900024162, on 28 June 2019.


Assuntos
Dexmedetomidina , Interleucina-6 , Complicações Pós-Operatórias , Fator de Necrose Tumoral alfa , Humanos , Dexmedetomidina/administração & dosagem , Dexmedetomidina/farmacologia , Masculino , Feminino , Idoso , Complicações Pós-Operatórias/prevenção & controle , Pessoa de Meia-Idade , Interleucina-6/sangue , Fator de Necrose Tumoral alfa/sangue , Inflamação/prevenção & controle , China , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Método Duplo-Cego , Procedimentos Cirúrgicos do Sistema Biliar/efeitos adversos , Injúria Renal Aguda/prevenção & controle , Injúria Renal Aguda/etiologia
3.
Quant Imaging Med Surg ; 14(6): 3914-3922, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38846312

RESUMO

Background: Limited information exists regarding susceptibility vessel sign (SVS) found beyond 24 hours after stroke onset. This study aimed to compare the presence and quantitative measurements of SVS between the large artery arteriosclerosis (LAA) subtype and the cardioembolism (CE) subtype in patients with subacute stroke. Methods: We retrospectively analyzed stroke survivors with the LAA subtype or the CE subtype who had occlusion or severe stenosis of the responsible intracranial large vessel and who had undergone susceptibility-weighted imaging (SWI) between day 3 and day 14 after stroke onset at Peking University First Hospital from December 2017 to January 2022. Independent reviewers evaluated the presence, location, length, and diameter of SVS. Multivariable logistic regression analysis was used to analyze the relationship between the presence of SVS and stroke subtype. Results: Among 173 stroke survivors, including 133 with the LAA subtype and 40 with the CE subtype, SVS was found in 95 patients. The presence of SVS was higher in the LAA group than in the CE group (59.4% vs. 40.0%; P=0.031), and this difference remained statistically significant in multivariable analysis [odds ratio (OR) =2.199; 95% confidence interval (CI): 1.019-4.745; P=0.045]. The LAA group had a longer SVS than did the CE group (20.7±10.6 vs. 13.8±5.1 mm; P<0.001). Conclusions: In patients with subacute ischemic stroke caused by intracranial large vessel occlusion (LVO) or severe stenosis, the LAA group had a higher incidence and a longer SVS than did the CE group. This suggests that SVS may have potential value in the etiology diagnosis of patients with subacute stroke.

4.
Int Immunopharmacol ; 136: 112361, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38820961

RESUMO

OBJECTIVE: Natural killer (NK) cells are an integral part of the staunch defense line against malignant tumors within the tumor microenvironment. Existing research indicates that miRNAs can influence the development of NK cells by negatively modulating gene expression. In this study, we aim to explore how the miR-17-5p in Hepatocellular Carcinoma (HCC) exosomes regulates the killing function of NK cells towards HCC cells through the transcription factor RNX1. METHODS: The exosomes were isolated from HCC tissues and cell lines, followed by a second generation sequencing to compare differential miRNAs. Verification was performed using qRT-PCR and Western blot methods. The mutual interactions between miR-17-5p and RUNX1, as well as between RUNX1 and NKG2D, were authenticated using techniques like luciferase reporter gene assays, Western blotting, and Chromatin Immunoprecipitation (ChIP). The cytotoxic activity of NK cells towards HCC cells in vitro was measured using methods such as RTCA and ELISPOT. The zebrafish xenotransplantation was utilized to assess the in vivo killing capacity of NK cells against HCC cells. RESULTS: The level of miR-17-5p in exosomes from HCC tissue increased compared to adjacent tissues. We verified that RUNX1 was a target of miR-17-5p and that RUNX1 enhances the transcription of NKG2D. MiR-17-5p was found to downregulate the expression of RUNX1 and NKG2D, subsequently reducing the in vitro and in vivo cytotoxic capabilities of NK cells against HCC cells. CONCLUSIONS: The miR-17-5p found within HCC exosomes can target RUNX1, subsequently attenuating the cytotoxic activity of NK cells.


Assuntos
Carcinoma Hepatocelular , Subunidade alfa 2 de Fator de Ligação ao Core , Exossomos , Regulação Neoplásica da Expressão Gênica , Células Matadoras Naturais , Neoplasias Hepáticas , MicroRNAs , Subfamília K de Receptores Semelhantes a Lectina de Células NK , MicroRNAs/genética , MicroRNAs/metabolismo , Humanos , Exossomos/metabolismo , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Animais , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Linhagem Celular Tumoral , Peixe-Zebra , Regulação para Baixo , Citotoxicidade Imunológica
5.
Exp Cell Res ; 439(1): 114073, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38704079

RESUMO

Determining the appropriate source of antigens for optimal antigen presentation to T cells is a major challenge in designing dendritic cell (DC) -based therapeutic strategies against hepatocellular carcinoma (HCC). Tumor-derived exosomes (Tex) express a wide range of tumor antigens, making them a promising source of antigens for DC vaccines. As reported, the exosomes secreted by tumor cells can inhibit the antitumor function of immune cells. In this study, we transfected hepatocellular carcinoma cells with Rab27a to enhance the yield of exosomes, which were characterized using transmission electron microscopy and Western blot analysis. We found that Tex secreted by overexpressing Rab27a Hepatocellular carcinoma cell lines pulsed DC is beneficial for the differentiation and maturation of DCs but inhibits the secretion of the IL-12 cytokine. Consequently, we developed a complementary immunotherapy approach by using Tex as an antigen loaded onto DCs, in combination with the cytokine IL-12 to induce antigen-specific cytotoxic T lymphocytes (CTLs). The results indicated that the combination of DC-Tex and IL-12 was more effective in stimulating T lymphocyte proliferation, releasing IFN-γ, and enhancing cytotoxicity compared to using exosomes or IL-12 alone. Additionally, the inclusion of IL-12 also compensated for the reduced IL-2 secretion by DCs caused by Tex. Moreover, in a BALB/c nude mice model of hepatocellular carcinoma, CTLs induced by DC-Tex combined with IL-12 maximized the tumor-specific T-cell immune effect and suppressed tumor growth. Thus, Tex provides a novel and promising source of antigens, with cytokines compensating for the shortcomings of Tex as a tumor antigen. This work helps to clarify the role of exosomes in tumor immunotherapy and may offer a safe and effective prospective strategy for the clinical application of exosome-based cellular immunotherapy.


Assuntos
Carcinoma Hepatocelular , Células Dendríticas , Exossomos , Interleucina-12 , Neoplasias Hepáticas , Proteínas rab27 de Ligação ao GTP , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Exossomos/metabolismo , Animais , Interleucina-12/metabolismo , Interleucina-12/genética , Proteínas rab27 de Ligação ao GTP/metabolismo , Proteínas rab27 de Ligação ao GTP/genética , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Camundongos , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Humanos , Linhagem Celular Tumoral , Proliferação de Células , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Camundongos Endogâmicos BALB C , Imunoterapia/métodos
6.
Front Microbiol ; 15: 1384991, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800755

RESUMO

Introduction: Rapid identification of infected individuals through viral RNA or antigen detection followed by effective personal isolation is usually the most effective way to prevent the spread of a newly emerging virus. Large-scale detection involves mass specimen collection and transportation. For biosafety reasons, denaturing viral transport medium has been extensively used during the SARS-CoV-2 pandemic. However, the high concentrations of guanidinium isothiocyanate (GITC) in such media have raised issues around sufficient GITC supply and laboratory safety. Moreover, there is a lack of denaturing transport media compatible with SARS-CoV-2 RNA and antigen detection. Methods: Here, we tested whether supplementing media containing low concentrations of GITC with ammonium sulfate (AS) would affect the throat-swab detection of SARS-CoV-2 or a viral inactivation assay targeting coronavirus and other enveloped and non-enveloped viruses. The effect of adding AS to the media on RNA stability and its compatibility with SARS-CoV-2 antigen detection were also tested. Results and discussion: We found that adding AS to the denaturing transport media reduced the need for high levels of GITC, improved SARS-COV-2 RNA detection without compromising virus inactivation, and enabled the denaturing transport media compatible with SARS-CoV-2 antigen detection.

8.
Front Cell Dev Biol ; 12: 1313610, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481526

RESUMO

Background: Patients with Triple-negative breast cancer (TNBC) face a poor prognosis and limited therapeutic options. Current data on eribulin usage to treat TNBC is scarce. Therefore, we sought to compare the feasibility and tolerability of eribulin-based regimens with other chemotherapy regimens in patients with TNBC. Method: This retrospective study was conducted at Fujian Medical University Cancer Hospital and included 159 patients with TNBC enrolled between October 2011 and January 2023. Patients underwent treatment with eribulin-based and other chemotherapy regimens. The study's primary endpoints were progression-free survival (PFS) and overall survival (OS), while its secondary endpoint was objective response rate (ORR), disease control rate (DCR), and safety. Tumour response was assessed using RECIST V.1.1 criteria. Results: Of the 159 participants in the study, 42 individuals (26.4%) received treatment with eribulin, whereas 117 participants (73.6%) were administered alternative chemotherapy regimens, which included nab-paclitaxel-based therapy (n = 45) and platinum-based therapy (n = 51). The follow-up period for all patients ended on 31 December 2022, and the median follow-up time was 18.3 months (range:0.7-27.5). Following propensity score matching (PSM), eribulin-based treatment resulted in longer median progression-free survival compared to platinum-based (hazard ratio (HR) = 0.41, p = 0.006), nab-paclitaxel-based (hazard ratio = 0.36, p = 0.001) and other chemotherapy (HR = 0.39, p < 0.001). Also, eribulin induced a remarkable prolongation of the median overall survival duration in all three comparative groups. The group receiving eribulin treatment showed significantly reduced incidences of any grade of anaemia, peripheral neuropathy, nausea and vomiting, and hair loss compared to other chemotherapy groups. Conclusion: For the salvage treatment of advanced TNBC, treatment with eribulin produced longer median PFS and OS than other chemotherapy regimens, with a well-tolerated safety profile. Therefore, further investigation of eribulin-based treatment in larger randomized trials for patients with advanced TNBC is warranted.

9.
BMC Neurol ; 24(1): 64, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360588

RESUMO

BACKGROUND: Vast economic and healthcare status discrepancies exist among regions in China, contributing to different treatment patterns. This study was aimed to investigate the current status of pharmacotherapy for acute ischemic stroke (AIS) and outcomes in China and explore the geographic variation in stroke care. METHODS: This study was a multicenter prospective registry study, which collected the data of patients with AIS from 80 hospitals in 46 cities in 2015-2017 across China. Poor functional outcome defined as a modified Rankin Scale score of 3-6 was assessed at 3 and 12 months. Multivariate logistic regression was used. RESULTS: Among 9973 eligible patients, the number of receiving intravenous thrombolysis (IVT), antiplatelet agents, anticoagulants, statin and human urinary kallidinogenase was 429 (4.3%), 9363 (93.9%), 1063 (10.7%), 6828 (74.7%) and 5112 (51.2%), respectively. Multivariable analysis showed IVT use in northeastern was significantly more frequent than in eastern region (OR = 3.17, 95% CI, 2.53-3.99), while the antiplatelets agents use were less frequent (OR = 0.46, 95%CI: 0.38-0.57). The proportions of poor outcomes at 3 and 12 months were 20.7% and 15.8%, respectively. Multivariate analysis showed AIS patients from northeastern and central region had significantly lower risk of poor outcome at month 3 and 12 than those from eastern region (all P < 0.05). CONCLUSIONS: There was a low IVT use and a high antiplatelet agent and statin use for AIS in China. The pharmacotherapy and prognosis of AIS had variation by geographic region. TRIAL REGISTRATION: This study was registered with ClinicalTrials.gov (NCT02470624).


Assuntos
Isquemia Encefálica , Inibidores de Hidroximetilglutaril-CoA Redutases , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/epidemiologia , Fibrinolíticos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , AVC Isquêmico/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/epidemiologia , Terapia Trombolítica , Resultado do Tratamento , Estudos Prospectivos
10.
J Hazard Mater ; 465: 133317, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38218031

RESUMO

Antibiotics affect bacterial community structure and functions in soil. However, the response and adaptation of root-associated bacterial communities to antibiotic stress remains poorly understood. Here, rhizobox experiments were conducted with maize (Zea mays L.) upon exposure to antibiotics ciprofloxacin or tetracycline. High-throughput sequencing analysis of bacterial community and quantitative PCR analysis of nitrogen cycling genes show that ciprofloxacin and tetracycline significantly shift bacterial community structure in bulk soil, whereas plant host may mitigate the disturbances of antibiotics on bacterial communities in root-associated niches (i.e., rhizosphere and rhizoplane) through the community stabilization. Deterministic assembly, microbial interaction, and keystone species (e.g., Rhizobium and Massilia) of root-associated bacterial communities benefit the community stability compared with those in bulk soil. Meanwhile, the rhizosphere increases antibiotic dissipation, potentially reducing the impacts of antibiotics on root-associated bacterial communities. Furthermore, rhizospheric effects deriving from root exudates alleviate the impacts of antibiotics on the nitrogen cycle (i.e., nitrification, organic nitrogen conversion and denitrification) as confirmed by functional gene quantification, which is largely attributed to the bacterial community stability in rhizosphere. The present study enhances the understanding on the response and adaptation of root-associated bacterial community to antibiotic pollution.


Assuntos
Antibacterianos , Bactérias , Bactérias/genética , Zea mays/microbiologia , Solo , Tetraciclina , Ciprofloxacina , Nitrogênio , Microbiologia do Solo , Rizosfera , Raízes de Plantas/microbiologia
11.
BMC Cancer ; 24(1): 39, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182995

RESUMO

PURPOSE: This investigation sought to examine the efficacy and safety of low-dose apatinib used alongside chemotherapy in the clinical management of patients with metastatic triple-negative breast cancer (TNBC) within a real-world setting, whilst comparing the outcomes with those treated solely with chemotherapy. METHODS: This case series study analyzed clinical data and treatment outcomes of 163 patients with metastatic TNBC who underwent rescue treatment at the Medical Oncology Department of Clinical Oncology, Fujian Cancer Hospital, School of Fujian Medical University, China, between October 2011 and January 2023. All the patients underwent rescue treatment with either chemotherapy alone or apatinib (250 mg/day) combined with chemotherapy. The study's primary outcome was progression-free survival (PFS), whereas the secondary outcomes included overall survival (OS), objective response rate (ORR), disease control rate (DCR), and safety profiles. RESULTS: The study was designed to compare two groups [1]. Out of the 163 TNBC patients who participated in the study, 107 individuals (65.6%) received treatment based on chemotherapy, whereas 56 patients (34.4%) were given treatment based on a combination of low-dose apatinib (250 mg/day) and other treatments, including chemotherapy. After propensity score matching (PSM), the objective response rate (ORR) and disease control rate (DCR) of patients with advanced triple-negative breast cancer (TNBC) who received apatinib-based treatment were 50.0 and 90.0%, respectively, while they were 6.7 and 20.0%, respectively, for the chemotherapy-based group (P < 0.001). The group that received apatinib-based treatment showed superior results in both PFS and OS compared to the group that received chemotherapy. The median PFS and OS for the apatinib-based group were 7.8 and 20.3 months, respectively, while they were only 2.2 months and 9.0 months, respectively, for the chemotherapy-based group (P < 0.001) [2]. Patients who were administered combo therapies, including PD-1 inhibitors, were excluded. In total, 97 patients received chemotherapy alone, while 34 patients were treated with apatinib in combination with chemotherapy. After propensity score matching (PSM), the ORR and DCR for the total group who received combo therapies were 44.4 and 81.5%, respectively, while they were 11.1 and 22.2%, respectively, for the chemotherapy alone group (P < 0.001). The group receiving both apatinib and chemotherapy displayed notable advantages over the group solely receiving chemotherapy in regards to PFS and OS for the entirety of the population. The PFS was found to be 7.8 months in comparison to 2.1 months (P < 0.001) and the OS was 21.1 months in contrast to 9.0 months (P < 0.001). Apatinib combined with chemotherapy induced grade 3/4 hematological toxicities, including neutropenia (8.8%) and thrombocytopenia (2.9%). Additionally, non-hematological toxicities were commonly observed, such as Hand-foot syndrome (35.3%), proteinuria (26.5%), hypertension (61.8%), higher alanine aminotransferase levels (26.5%), and fatigue (35.3%). The most frequent non-hematological grade 3/4 toxicities were Hand-foot syndrome (2.9%) and hypertension (5.9%). The study did not report any fatal adverse effects. CONCLUSIONS: The combination of low-dose apatinib with chemotherapy has proven to be more effective than chemotherapy alone in treating metastatic triple-negative breast cancer (TNBC). Additionally, the occurrence of grade 3/4 non-hematologic toxicities was significantly lower compared to the recommended dose of apatinib.


Assuntos
Síndrome Mão-Pé , Hipertensão , Leucopenia , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Protocolos Clínicos
12.
Neurocrit Care ; 40(1): 225-236, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37208490

RESUMO

BACKGROUND: Iron overload plays an important role in hydrocephalus development following intraventricular hemorrhage (IVH). Aquaporin 4 (AQP4) participates in the balance of cerebrospinal fluid secretion and absorption. The current study investigated the role of AQP4 in the formation of hydrocephalus caused by iron overload after IVH. METHODS: There were three parts to this study. First, Sprague-Dawley rats received an intraventricular injection of 100 µl autologous blood or saline control. Second, rats had IVH and were treated with deferoxamine (DFX), an iron chelator, or vehicle. Third, rats had IVH and were treated with 2-(nicotinamide)-1,3,4-thiadiazole (TGN-020), a specific AQP4 inhibitor, or vehicle. Rats underwent T2-weighted and T2* gradient-echo magnetic resonance imaging to assess lateral ventricular volume and intraventricular iron deposition at 7, 14, and 28 days after intraventricular injection and were then euthanized. Real-time quantitative polymerase chain reaction, western blot analysis, and immunofluorescence analyses were conducted on the rat brains to evaluate the expression of AQP4 at different time points. Hematoxylin and eosin-stained brain sections were obtained to assess the ventricular wall damage on day 28. RESULTS: Intraventricular injection of autologous blood caused a significant ventricular dilatation, iron deposition, and ventricular wall damage. There was increased AQP4 mRNA and protein expression in the periventricular tissue in IVH rats through day 7 to day 28. The DFX treatment group had a lower lateral ventricular volume and less intraventricular iron deposition and ventricular wall damage than the vehicle-treated group after IVH. The expression of AQP4 protein in periventricular tissue was also inhibited by DFX on days 14 and 28 after IVH. The use of TGN-020 attenuated hydrocephalus development after IVH and inhibited the expression of AQP4 protein in the periventricular tissue between day 14 and day 28 without a significant effect on intraventricular iron deposition or ventricular wall damage. CONCLUSIONS: AQP4 located in the periventricular area mediated the effect of iron overload on hydrocephalus after IVH.


Assuntos
Hidrocefalia , Sobrecarga de Ferro , Niacinamida , Tiadiazóis , Animais , Ratos , Aquaporina 4/uso terapêutico , Hemorragia Cerebral/tratamento farmacológico , Hidrocefalia/etiologia , Injeções Intraventriculares , Ferro/metabolismo , Sobrecarga de Ferro/complicações , Niacinamida/análogos & derivados , Ratos Sprague-Dawley
13.
J Opt Soc Am A Opt Image Sci Vis ; 40(12): 2187-2196, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38086027

RESUMO

To improve the performance of underwater wireless optical communication (UWOC) systems, we propose a relay-assisted UWOC system model based on adaptive optics (AO). The closed expressions of the scintillation index, composite channel probability density function, and outage probability of the Gaussian beam before and after AO compensation are derived using the extended Rytov theory and Meijer G-function. The performance variation of an UWOC system with different parameters is analyzed by simulation. The results show that AO correction can compensate for the distorted wavefront and significantly reduce the intensity fluctuation at the receiving end. The proposed system can efficiently alleviate channel fading, improving the outage probability performance of the UWOC system.

14.
Molecules ; 28(23)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38067497

RESUMO

Owing to high efficacy and safety, natural medicines have found their way into the field of cancer therapy over the past few decades. However, the effective ingredients of natural medicines have shortcomings of poor solubility and low bioavailability. Nanoparticles can not only solve the problems above but also have outstanding targeting ability. Targeting preparations can be classified into three levels, which are target tissues, cells, and organelles. On the premise of clarifying the therapeutic purpose of drugs, one or more targeting methods can be selected to achieve more accurate drug delivery and consequently to improve the anti-tumor effects of drugs and reduce toxicity and side effects. The aim of this review is to summarize the research status of natural medicines' nano-preparations in tumor-targeting therapies to provide some references for further accurate and effective cancer treatments.


Assuntos
Nanopartículas , Neoplasias , Humanos , Nanotecnologia , Preparações Farmacêuticas , Sistemas de Liberação de Medicamentos , Disponibilidade Biológica , Neoplasias/tratamento farmacológico , Neoplasias/patologia
15.
Quant Imaging Med Surg ; 13(10): 6854-6862, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37869347

RESUMO

Background: Intraventricular hemorrhage (IVH) after intracerebral hemorrhage (ICH) is a strong independent predictor of poor outcomes. Although the location and volume of ICH are associated with IVH, our knowledge concerning the mechanism of IVH after ICH is still limited. This study aimed to investigate the relationship between hematoma morphology and IVH in patients with supratentorial deep ICH. Methods: We retrospectively analyzed adult patients (aged ≥18 years) with spontaneous supratentorial deep ICH who underwent computed tomography (CT) within 48 h after ICH symptom onset in Peking University First Hospital between January 2017 and August 2022. We collected the clinical and imaging data of the patients and assessed hematoma morphology using several quantitative radiological parameters including hematoma volume, sphericity index, A/B ratio (A: the largest area of hematoma; B: the largest diameter 90° to A on the same slice), and our newly proposed largest diameter-midline angle (LMA). Multivariable logistic regression analysis was used to analyze the relationship between these parameters and the presence of IVH on the initial CT scan. Results: Among 114 patients with spontaneous supratentorial deep ICH, 41 (36.0%) had IVH. In patients with IVH, the sphericity index was lower than that in individuals without IVH, while the LMA was larger. Multivariate logistic regression analysis showed that sphericity index [0.1-unit odds ratio (OR) =0.252; 95% CI: 0.089-0.709; P=0.009] and the LMA (10-unit OR =1.281; 95% CI: 1.007-1.630; P=0.04) were independently associated with the presence of IVH in patients with supratentorial deep ICH. Univariate analyses showed that hematoma volume, A/B ratio, sphericity index, and the LMA were significantly associated with poor outcomes at discharge. Conclusions: Two quantitative parameters of hematoma morphology, sphericity index and the LMA, were significantly associated with the presence of IVH in patients with supratentorial deep ICH. Further prospective studies with larger sample sizes are needed to validate our results.

16.
JAMA Neurol ; 80(10): 1115-1116, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37669057

RESUMO

This case report describes epilepsy in a 50-year-old patient with brain herniation into the arachnoid granulation.

17.
Nat Commun ; 14(1): 5722, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37714854

RESUMO

Circular RNAs have been extensively studied in eukaryotes, but their presence and/or biological functionality in bacteria are unclear. Here, we show that a regulatory noncoding RNA (DucS) exists in both linear and circular conformation in Bacillus altitudinis. The linear forms promote B. altitudinis tolerance to H2O2 stress, partly through increased translation of a stress-responsive gene, htrA. The 3' end sequences of the linear forms are crucial for RNA circularization, and formation of circular forms can decrease the levels of the regulatory linear cognates. Bioinformatic analysis of available RNA-seq datasets from 30 bacterial species revealed multiple circular RNA candidates, distinct from DucS, for all the examined species. Experiments testing for the presence of selected circular RNA candidates in four species successfully validated 7 out of 9 candidates from B. altitudinis and 4 out of 5 candidates from Bacillus paralicheniformis; However, none of the candidates tested for Bacillus subtilis and Escherichia coli were detected. Our work identifies a dual-conformation regulatory RNA in B. altitutidinis, and indicates that circular RNAs exist in diverse bacteria. However, circularization of specific RNAs does not seem to be conserved across species, and the circularization mechanisms and biological functionality of the circular forms remain unclear.


Assuntos
Peróxido de Hidrogênio , RNA Circular , RNA Circular/genética , Peróxido de Hidrogênio/toxicidade , RNA não Traduzido/genética , Estresse Oxidativo/genética , RNA , Escherichia coli
18.
Environ Monit Assess ; 195(9): 1029, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37558900

RESUMO

The disturbance characteristics and driving factors of human activity intensity in national parks are important factors affecting environmental change in ecological function areas. In-depth analysis of these must be the basis of improving the ecological environment in northwest China. This study selected data related to human activities from 2000 to 2020 to analyze the comprehensive impact of human interference on national park development and found that the NDVI (Normalized Difference Vegetation Index) of Qilian Mountain National Park showed an increasing trend and that the NPP (net primary productivity) showed spatial distribution characteristics of decreasing from east to west during the study period. This showed that human interference in and around the national park was changing significantly and that the high value area was gradually shifting southward. In the first decade, economic and social development was slow; related industries such as industry, tourism, and modern agriculture were not introduced on a large scale; and the ecological environment was in relatively good condition, with relatively weak human interference. However, in the second decade, human interference was prominent, with deeper ecological damage, but rapid economic development. Infrastructure development, population urbanization, and traditional production and living practices were the main factors driving changes in human interference. The Chinese government's proposed green building policy will further reduce the ecological impact of human activities while ensuring economic development. Building upon this, the present paper puts forth a "zero-disturbance" framework for national parks, aiming to offer recommendations for the future development of such parks.


Assuntos
Ecossistema , Parques Recreativos , Humanos , Monitoramento Ambiental , Conservação dos Recursos Naturais , China
19.
IEEE Trans Pattern Anal Mach Intell ; 45(12): 15912-15929, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37494162

RESUMO

Contrastive learning, which aims to capture general representation from unlabeled images to initialize the medical analysis models, has been proven effective in alleviating the high demand for expensive annotations. Current methods mainly focus on instance-wise comparisons to learn the global discriminative features, however, pretermitting the local details to distinguish tiny anatomical structures, lesions, and tissues. To address this challenge, in this paper, we propose a general unsupervised representation learning framework, named local discrimination (LD), to learn local discriminative features for medical images by closely embedding semantically similar pixels and identifying regions of similar structures across different images. Specifically, this model is equipped with an embedding module for pixel-wise embedding and a clustering module for generating segmentation. And these two modules are unified by optimizing our novel region discrimination loss function in a mutually beneficial mechanism, which enables our model to reflect structure information as well as measure pixel-wise and region-wise similarity. Furthermore, based on LD, we propose a center-sensitive one-shot landmark localization algorithm and a shape-guided cross-modality segmentation model to foster the generalizability of our model. When transferred to downstream tasks, the learned representation by our method shows a better generalization, outperforming representation from 18 state-of-the-art (SOTA) methods and winning 9 out of all 12 downstream tasks. Especially for the challenging lesion segmentation tasks, the proposed method achieves significantly better performance.


Assuntos
Algoritmos , Aprendizado de Máquina não Supervisionado , Análise por Conglomerados , Processamento de Imagem Assistida por Computador
20.
IEEE Trans Pattern Anal Mach Intell ; 45(11): 13796-13813, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37494163

RESUMO

Text-to-SQL is the task of converting a natural language utterance plus the corresponding database schema into a SQL program. The inputs naturally form a heterogeneous graph while the output SQL can be transduced into an abstract syntax tree (AST). Traditional encoder-decoder models ignore higher-order semantics in heterogeneous graph encoding and introduce permutation biases during AST construction, thus incapable of exploiting the refined structure knowledge precisely. In this work, we propose a generic heterogeneous graph to abstract syntax tree (HG2AST) framework to integrate dedicated structure knowledge into statistics-based models. On the encoder side, we leverage a line graph enhanced encoder (LGESQL) to iteratively update both node and edge features through dual graph message passing and aggregation. On the decoder side, a grammar-based decoder first constructs the equivalent SQL AST and then transforms it into the desired SQL via post-processing. To avoid over-fitting permutation biases, we propose a golden tree-oriented learning (GTL) algorithm to adaptively control the expanding order of AST nodes. The graph encoder and tree decoder are combined into a unified framework through two auxiliary modules. Extensive experiments on various text-to-SQL datasets, including single/multi-table, single/cross-domain, and multilingual settings, demonstrate the superiority and broad applicability.

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