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1.
Chem Asian J ; : e202400515, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899858

RESUMO

Two hydroxy rich hypercrosslinked POPs, namely Ph/Tt-POP have been developed by facile one-pot condensation polymerization strategy. The high surface areas of both the Ph/Tt-POP (1057 and 893 m2g-1, respectively), and the heteroatom functionality in the POP framework instigated us to explore our material for CO2 adsorption study. The CO2 uptake capacities in Ph/Tt-POP are found to be 2.45 and 2.2 mmol g-1, at 273 K respectively. in-situ static 13C NMR experiment shows that CO2 molecules in Tt-POP appear to be less mobile than those in Ph-POP which probably due to the presence of triazine functional groups along with high abundant -OH groups in the Tt-POP framework. An in-depth study of the CO2 adsorption mechanism by density functional theory (DFT) calculations also shows that CO2 adsorption at the cages formed by two benzyl rings represents the most stable interaction and CO2 molecule is more favorably adsorbed on the Ph-POP with the more negative interaction energies values compared to that of Tt-POP. Non-covalent interaction (NCI) plot revealed that CO2 molecule is adsorbed more on the Ph-POP than Tt-POP, which can be explained by hydrogen bond formation in case of Tt-POP repeating units turning aside CO2 molecule to interact with the Ph component.

2.
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
3.
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.

4.
Cancers (Basel) ; 15(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37509336

RESUMO

Patients with breast cancer undergoing chemotherapy are susceptible to prolonged and severe neutropenia. Multiple biosimilars of long-acting granulocyte colony-stimulating factors (LA-G-CSFs) have been newly developed to prevent this disease. Nonetheless, which LA-G-CSF regimen has the optimal balance of efficacy and safety remains controversial. Moreover, there is a lack of evidence supporting clinical decisions on LA-G-CSF dose escalation in poor conditions. PubMed, Embase, Cochrane Library, Web of Science, and several Chinese databases were searched (December 2022) to collect randomized controlled trials (RCTs) about LA-G-CSFs preventing chemotherapy-induced neutropenia in breast cancer patients. No restrictions were imposed on language. A Bayesian network meta-analysis was performed. We assessed the incidence of severe neutropenia (SN) and febrile neutropenia (FN), the duration of SN (DSN), and the absolute neutrophil account recovery time (ANCrt) for efficacy, while the incidence of severe adverse events (SAE) was assessed for safety. The study was registered in PROSPERO (CRD42022361606). A total of 33 RCTs were included. Our network meta-analysis demonstrated that lipegfilgrastim 6 mg and eflapegrastim 13.2 mg outperformed other LA-G-CSFs with high efficacy rates and few safety concerns (SUCRA of lipegfilgrastim 6 mg: ANC rt 95.2%, FN 97.4%; eflapegrastim 13.2 mg: FN 87%, SN 89.3%). Additionally, 3.6 mg, 4.5 mg, 6 mg, and 13.2 mg dosages all performed significantly better than 1.8 mg in reducing the duration of SN (3.6 mg: DSN, SMD -0.68 [-1.13, -0.22; moderate]; 4.5 mg: -0.87 [-1.57, -0.17; low]; 6 mg: -0.89 [-1.49, -0.29; moderate]; 13.2 mg: -1.02 [1.63, -0.41; high]). Increasing the dosage from the guideline-recommended 6 mg to 13.2 mg can reduce both the duration and incidence of SN (SMD -0.13 [-0.24 to -0.03], RR 0.65 [0.43 to 0.96], respectively), with no significant difference in SAE. For patients with breast cancer, lipegfilgrastim 6 mg and eflapegrastim 13.2 mg might be the most effective regimen among LA-G-CSFs. Higher doses of LA-G-CSF may enhance efficacy without causing additional SAEs.

5.
J Diabetes ; 15(10): 853-865, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37329140

RESUMO

BACKGROUND: Arterial stiffness contributes to additional cardiovascular risks in diabetic patients by triggering the loss of vascular and myocardial compliance and promoting endothelial dysfunction. Thus, prevention of arterial stiffness is a public health priority, and the identification of potential biomarkers may provide benefits for early prevention. This study investigates the relationships between serum laboratory tests and pulse wave velocity (PWV) tests. We also investigated the associations between PWV and all-cause mortality. METHODS: We examined a panel of 33 blood biomarkers among diabetic populations in the Atherosclerosis Risk in Communities Study. The carotid-femoral (cfPWV) and femoral-ankle PWV (faPWV) were measured using an automated cardiovascular screening device. The aortic-femoral arterial stiffness gradient (afSG) was calculated as faPWV divided by cfPWV. Biomarker levels were log-transformed and correlated with PWV. Cox proportional hazard models were employed for survival analysis. RESULTS: Among 1079 diabetic patients, biomarkers including high-density lipoprotein cholesterol, glycated hemoglobin, high-sensitivity troponin T, cystatin C, creatinine, and albuminuria were significantly correlated with afSG (R = 0.078, -0.193, -0.155, -0.153, -0.116, and -0.137, respectively) and cfPWV (R = -0.068, 0.175, 0.128, 0.066, 0.202, and 0.062, respectively). Compared with the lowest tertile of afSG, the risk of all-cause mortality was lower in the highest tertile (hazard ratio 0.543; 95% confidence interval 0.328-0.900). CONCLUSION: Certain biomarkers related to blood glucose monitoring, myocardial injury, and renal function significantly correlated with PWV, suggesting that these putative risk factors are likely to be important atherosclerosis mechanisms in diabetic patients. AfSG may be an independent predictor of mortality among diabetic populations.

6.
J Neurol ; 270(10): 4939-4948, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37356023

RESUMO

OBJECTIVE: To quantitatively evaluate cerebral small vessel disease (CSVD) in brain magnetic resonance imaging (MRI) and its correlation with disease burden and markers in Fabry disease, a rare X-linked lysosomal storage disease. METHODS: We collected brain MRI data from seventy-one Chinese patients with Fabry disease. CSVD was evaluated using an age-related white matter change rating scale, Fazekas scale, enlarged perivascular spaces grading scale, lacunar infarction scale, Microbleed Anatomical Rating Scale, global cortical atrophy scale, and small-vessel disease score. Factors associated with MRI lesions, including sex, clinical subtype, disease severity, disease burden, genotype, and biomarkers, were also analyzed. RESULTS: Of 71 patients, 16 (22.5%) experienced ischemic stroke. The incidences of lacunar infarctions, white matter hyperintensities, and cerebral microbleeds were 55%, 62%, and 33%, respectively. The abnormal MRI group had later disease onset, longer disease duration, and a higher Mainz Severity Score Index (p < 0.05) than the normal MRI group. Patients with more severe clinical phenotypes also had higher CVSD-related scores. Sex and GLA mutational type were not closely associated with brain MRI lesions. Of the disease markers, the Mainz Severity Score Index and plasma globotriaosylsphingosine (Lyso-Gb3) were closely correlated with the majority of the MRI scores, whereas α-galactosidase A activity was not. CONCLUSION: Brain MRI revealed progressive lacunar infarctions, white matter hyperintensities, and decreased brain volume in patients with Fabry disease. Brain MRI lesions were closely related to onset-age; disease duration, severity, burden; and plasma Lyso-Gb3. However, they were not associated with sex, α-galactosidase A activity, or GLA mutation type.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Doença de Fabry , Acidente Vascular Cerebral Lacunar , Humanos , Doença de Fabry/diagnóstico por imagem , Acidente Vascular Cerebral Lacunar/diagnóstico por imagem , Acidente Vascular Cerebral Lacunar/etiologia , alfa-Galactosidase/genética , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/complicações , Imageamento por Ressonância Magnética/métodos , Biomarcadores , Efeitos Psicossociais da Doença
7.
Int J Behav Nutr Phys Act ; 20(1): 59, 2023 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-37198574

RESUMO

BACKGROUND: Research on the association of physical activity and sedentary time with dementia is accumulating, though elusive, and the interaction effects of the two remain unclear. We analysed the joint associations of accelerometer-measured physical activity and sedentary time with risk of incident dementia (all-cause dementia, Alzheimer's disease and vascular dementia). METHODS: A total of 90,320 individuals from the UK Biobank were included. Accelerometer-measured total volume of physical activity (TPA) and sedentary time were measured at baseline and dichotomised by median (low TPA [< 27 milli-gravity (milli-g)], high TPA [≥ 27 milli-g]; low sedentary time [< 10.7 h/day], high sedentary time [≥ 10.7 h/day]). Cox proportional hazards models were used to evaluate the joint associations with incident dementia on both additive and multiplicative scales. RESULTS: During a median follow-up of 6.9 years, 501 cases of all-cause dementia were identified. Higher TPA was associated with a lower risk of all-cause dementia, Alzheimer's disease and vascular dementia; the multivariate adjusted hazard ratios (HRs) (95% CI) per 10 milli-g increase were 0.63 (0.55-0.71), 0.74 (0.60-0.90) and 0.69 (0.51-0.93), respectively. Sedentary time was only found to be linked to all-cause dementia, and the HR for high sedentary time was 1.03 (1.01-1.06) compared with that for low sedentary time. No additive and multiplicative relationship of TPA and sedentary time to incident dementia was found (all P values > 0.05). CONCLUSION: Higher TPA level was related to a lower risk of incident dementia irrespective of sedentary time, which highlighted the implication of promoting physical activity participation to counteract the potential detrimental effect of sedentary time on dementia.


Assuntos
Doença de Alzheimer , Demência Vascular , Humanos , Estudos de Coortes , Doença de Alzheimer/epidemiologia , Comportamento Sedentário , Bancos de Espécimes Biológicos , Estudos Prospectivos , Exercício Físico , Acelerometria , Reino Unido/epidemiologia , Fatores de Risco
8.
Front Nutr ; 10: 1284985, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38188879

RESUMO

Background and aims: Hypercholesterolemia has been identified as risk factor for severe acute pancreatitis (AP). We aimed to identify the common differentially expressed genes (DEGs) between a high-cholesterol diet and AP. Methods: We retrived gene expression profiles from the GEO database. DEGs were assessed using GEO2R. For AP hub genes, we conducted functional enrichment analysis and protein-protein interaction (PPI) analysis. GeneMANIA and correlation analysis were employed to predict potential DEG mechanisms. Validation was done across various healthy human tissues, pancreatic adenocarcinoma, peripheral blood in AP patients, and Sprague-Dawley rats with AP. Results: The gene "Fabp5" emerged as the sole common DEG shared by a high-cholesterol diet and AP. Using the 12 topological analysis methods in PPI network analysis, Rela, Actb, Cdh1, and Vcl were identified as hub DEGs. GeneMANIA revealed 77.6% physical interactions among Fabp5, TLR4, and Rela, while genetic correlation analysis indicated moderate associations among them. Peripheral blood analysis yielded area under the ROC curve (AUC) values of 0.71, 0.63, 0.74, 0.64, and 0.91 for Fabp5, TLR4, Actb, Cdh1 genes, and artificial neural network (ANN) model respectively, in predicting severe AP. In vivo immunohistochemical analysis demonstrated higher Fabp5 expression in the hyperlipidemia-associated AP group compared to the AP and control groups. Conclusion: Fabp5 emerged as the common DEG connecting a high-cholesterol diet and AP. Rela was highlighted as a crucial hub gene in AP. Genetic interactions were observed among Fabp5, TLR4, and Rela. An ANN model consisting of Fabp5, TLR4, Actb, and Cdh1 was helpful in predicting severe AP.

9.
Front Immunol ; 13: 862757, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35967294

RESUMO

VISTA (PD-1H) is an immune regulatory molecule considered part of the next wave of immuno-oncology targets. VISTA is an immunoglobulin (Ig) superfamily cell surface molecule mainly expressed on myeloid cells, and to some extent on NK cells and T cells. In previous preclinical studies, some VISTA-targeting antibodies provided immune inhibitory signals, while other antibodies triggered immune stimulatory signals. Importantly, for therapeutic antibodies, the isotype backbone can have a strong impact on antibody function. To elucidate the mode of action of immune stimulatory anti-VISTA antibodies, we studied three different anti-human VISTA antibody clones, each on three different IgG isotypes currently used for therapeutic antibodies: unaltered IgG1 (IgG1-WT), IgG1-KO (IgG1-LL234,235AA-variant with reduced Fc-effector function), and IgG4-Pro (IgG4- S228P-variant with stabilized hinge region). Antibody functionality was analysed in mixed leukocyte reaction (MLR) of human peripheral blood mononuclear cells (PBMCs), as a model system for ongoing immune reactions, on unstimulated human PBMCs, as a model system for a resting immune system, and also on acute myeloid leukemia (AML) patient samples to evaluate anti-VISTA antibody effects on primary tumor material. The functions of three anti-human VISTA antibodies were determined by their IgG isotype backbones. An MLR of healthy donor PBMCs was effectively augmented by anti-VISTA-IgG4-Pro and anti-VISTA-IgG1-WT antibodies, as indicated by increased levels of cytokines, T cell activation markers and T cell proliferation. However, in a culture of unstimulated PBMCs of single healthy donors, only anti-VISTA-IgG1-WT antibodies increased the activation marker HLA-DR on resting myeloid cells, and chemokine levels. Interestingly, interactions with different Fc-receptors were required for these effects, namely CD64 for augmentation of MLR, and CD16 for activation of resting myeloid cells. Furthermore, anti-VISTA-IgG1-KO antibodies had nearly no impact in any model system. Similarly, in AML patient samples, anti-VISTA-antibody on IgG4-Pro backbone, but not on IgG1-KO backbone, increased interactions, as a novel readout of activity, between immune cells and CD34+ AML cancer cells. In conclusion, the immune stimulatory effects of antagonistic anti-VISTA antibodies are defined by the antibody isotype and interaction with different Fc-gamma-receptors, highlighting the importance of understanding these interactions when designing immune stimulatory antibody therapeutics for immuno-oncology applications.


Assuntos
Antígenos B7/imunologia , Neoplasias , Receptores Fc , Humanos , Imunoglobulina G , Leucócitos Mononucleares , Receptores de IgG
10.
Diagnostics (Basel) ; 12(7)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35885587

RESUMO

In addition to Pseudomonas aeruginosa, other organisms including Staphylococcus aureus have been reported to have associations with ecthyma gangrenosum (EG). There are very limited reports of Staphylococcus aureus EG causing systemic symptoms in an immunocompetent child. We present the case of an atopic child with transient neutropenia developing characteristic skin lesions of EG. Culture of the skin wounds yielded methicillin-susceptible Staphylococcus aureus (MSSA), and incisional biopsy of the skin lesions revealed aggregates of Gram-positive cocci at the subepidermal area and necrotic vasculitis but without perivascular bacterial invasion. In the literature review, seven cases of Staphylococcus aureus EG were reported, and only two were pediatric cases. From this case, we emphasize the importance of early culturing for microorganisms in cases presenting with EG. When toxin-mediated systemic symptoms accompany EG-like skin lesions, MSSA should be considered in an atopic child with transient neutropenia.

11.
Front Mol Neurosci ; 15: 808209, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35677584

RESUMO

The relationship between body mass index (BMI) and cognitive impairment remains controversial, especially in older people. This study aims to confirm the association of phenotypic and genetic obesity with cognitive impairment and the benefits of adhering to a healthy lifestyle. This prospective study included 10,798 participants (aged ≥ 50 years) with normal cognitive function from the Health and Retirement Study in the United States. Participants were divided into low (lowest quintile), intermediate (quintiles 2-4), and high (highest quintile) groups according to their polygenic risk score (PRS) for BMI. The risk of cognitive impairment was estimated using Cox proportional hazard models. Higher PRS for BMI was associated with an increased risk, whereas phenotypic obesity was related to a decreased risk of cognitive impairment. Never smoking, moderate drinking, and active physical activity were considered favourable and associated with a lower risk of cognitive impairment compared with current smoking, never drinking, and inactive, respectively. A favourable lifestyle was associated with a low risk of cognitive impairment, even in subjects with low BMI and high PRS for BMI. This study suggest that regardless of obesity status, including phenotypic and genetic, adhering to a favourable lifestyle is beneficial to cognitive function.

13.
Chem ; 7(11): 3085-3098, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34825106

RESUMO

The trade-off between selectivity and adsorption capacity with porous materials is a major roadblock to reducing the energy footprint of gas separation technologies. To address this matter, we report herein a systematic crystal engineering study of C2H2 removal from CO2 in a family of hybrid ultramicroporous materials (HUMs). The HUMs are composed of the same organic linker ligand, 4-(3,5-dimethyl-1H-pyrazol-4-yl)pyridine, pypz, three inorganic pillar ligands, and two metal cations, thereby affording six isostructural pcu topology HUMs. All six HUMs exhibited strong binding sites for C2H2 and weaker affinity for CO2. The tuning of pore size and chemistry enabled by crystal engineering resulted in benchmark C2H2/CO2 separation performance. Fixed-bed dynamic column breakthrough experiments for an equimolar (v/v = 1:1) C2H2/CO2 binary gas mixture revealed that one sorbent, SIFSIX-21-Ni, was the first C2H2 selective sorbent that combines exceptional separation selectivity (27.7) with high adsorption capacity (4 mmol·g-1).

14.
Front Neurol ; 12: 727304, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650508

RESUMO

Background and Purpose: There is limited information on symptomatic intracranial hemorrhage (sICH) in stroke patients without thrombolysis. This study aimed to evaluate the risk factors of sICH and the association between sICH and the prognosis at 3 and 12 months in acute ischemic stroke patients without thrombolysis. Methods: Data originated from the Chinese Acute Ischemic Stroke Treatment Outcome Registry. Univariate analysis and multivariate logistic regression were used to screen the risk factors of sICH. Multivariable logistic regression models were used to assess the association of sICH with poor outcome and all-cause mortality. Results: Totally, 9,484 patients were included, of which 69 (0.73%) had sICH. Atrial fibrillation (odds ratio [OR], 3.682; 95% confidence interval [CI], 1.945-6.971; p < 0.001), history of tumors (OR, 2.956; 95% CI, 1.115-7.593; p = 0.024), and the National Institutes of Health Stroke Scale (NIHSS) score on admission ([6-15: OR, 2.344; 95% CI, 1.365-4.024; p = 0.002] [>15: OR, 4.731; 95% CI, 1.648-13.583; p = 0.004]) were independently associated with sICH. After adjustment of the confounders, patients with sICH had a higher risk of poor outcome (OR, 1.983; 95% CI, 1.117-3.521; p = 0.018) at 3 months and that of all-cause mortality at 3 (OR, 6.135; 95% CI, 2.328-16.169; p < 0.001) and 12 months (OR, 3.720; 95% CI, 1.513-9.148; p = 0.004). Conclusion: sICH occurred in 0.73% of acute ischemic stroke patients without thrombolysis and was associated with a worse prognosis at 3 and 12 months. Atrial fibrillation, history of tumors, and NIHSS score at admission were independent risk factors of sICH.

15.
J Cereb Blood Flow Metab ; 41(10): 2656-2675, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33899559

RESUMO

Chronic cerebral hypoperfusion, a major vascular contributor to vascular cognitive impairment and dementia, can exacerbate small vessel pathology. Connexin43, the most abundant gap junction protein in brain tissue, has been found to be critically involved in the pathological changes of vascular cognitive impairment and dementia caused by chronic cerebral hypoperfusion. However, the precise mechanisms underpinning its role are unclear. We established a mouse model via bilateral common carotid arteries stenosis on connexin43 heterozygous male mice and demonstrated that connexin43 improves brain blood flow recovery by mediating reparative angiogenesis under chronic cerebral hypoperfusion, which subsequently reduces the characteristic pathologies of vascular cognitive impairment and dementia including white matter lesions and irreversible neuronal injury. We additionally found that connexin43 mediates hypoxia inducible factor-1α expression and then activates the PKA signaling pathway to regulate vascular endothelial growth factor-induced angiogenesis. All the above findings were replicated in bEnd.3 cells treated with 375 µM CoCl2in vitro. These results suggest that connexin 43 could be instrumental in developing potential therapies for vascular cognitive impairment and dementia caused by chronic cerebral hypoperfusion.


Assuntos
Disfunção Cognitiva/fisiopatologia , Conexina 43/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Animais , Doença Crônica , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Transdução de Sinais
16.
Ann Palliat Med ; 10(7): 8371-8377, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33894705

RESUMO

There are many causes of bilateral thalamic lesions, but few cases of dural arteriovenous fistula (DAVF) associated with such lesions have been reported previously. Here, we describe an adult man with reversible rapid progressive dementia (RPD) in whom bilateral thalamic lesions were caused by a DAVF that had six supply arteries and drained into both the venous sinus and cortical veins. A 53-year-old man presented with memory decline and abnormal behavior. Head computed tomography (CT) revealed insignificant low density in the bilateral thalami and high density in the right occipital lobe. Brain magnetic resonance imaging showed hyperintensities in the thalami on T2-weighted images. Magnetic resonance venogram revealed no sign of the straight sinus, but multiple tortuous vessels in the cistern of the vein of Galen. Digital subtraction angiography revealed DAVFs near the tentorium cerebelli draining into the vein of Galen, which caused the vasogenic oedema of the thalami. The patient was then treated by transarterial embolization of the feeders. He gradually recovered after the surgery. RPD with bithalamic lesions caused by DAVF is rare but reversible. Therefore, the early recognition and intervention of DAVFs is crucial for the good prognosis of patients so that fistulas can be embolized in time.


Assuntos
Malformações Vasculares do Sistema Nervoso Central , Demência , Embolização Terapêutica , Adulto , Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Malformações Vasculares do Sistema Nervoso Central/terapia , Dura-Máter , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
17.
J Phys Chem B ; 124(44): 9773-9784, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33089692

RESUMO

Stabilizing G-quadruplex (G4) structures formed in the c-MYC oncogene promoter represents a fundamental strategy for cancer therapy. However, most G4 stabilizers lack selectivity over various G4s in the genomes. By investigating the binding characteristics of a conjugated imidazole/carbazole (IZCZ-3) molecule with the G4s of c-MYC, c-KIT, and telomere through molecular docking and molecular dynamics simulations, the present study demonstrates that though the binding affinities between IZCZ-3 and the monomeric G4s are inconsistent with the experimental data, the dimeric c-MYC and c-KIT G4s can be targeted by IZCZ-3 through forming concomitant π-π stacking interactions with the intermolecular assembly producing significant contributions to the binding affinity. In the intermolecular dimeric G4-IZCZ-3 binding complexes, IZCZ-3 prefers the c-MYC G4 that has two exposed G-tetrads per monomer over the single G-tetrad-exposed c-KIT G4 by creating more aggregation effects. Taking the aggregation effects into account, the binding affinity order of IZCZ-3 follows c-MYC G4 > c-KIT G4 > telomeric G4, agreeing well with the experimental observation. Thus, the selectivity of IZCZ-3 for c-MYC G4 probably comes from its role in stabilizing the sandwichlike intermolecular aggregates, providing a framework for the development of selective stabilizers targeting c-MYC G4.


Assuntos
Quadruplex G , Simulação de Dinâmica Molecular , Ligantes , Simulação de Acoplamento Molecular , Telômero/genética
18.
Biosci Rep ; 40(9)2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32830858

RESUMO

BACKGROUND: Sphingolipids mainly consist of ceramides (Cer), sphingomyelins (SM) and glycosphingolipids. Sphingolipids are related with coronary heart disease and metabolic disease, but there're few studies about cerebrovascular disease. The purpose was to detect sphingolipids in plasma of patients with large artery atherosclerosis (LAA) cerebrovascular disease and cerebral small vessel disease (CSVD) to explore the similarities and differences of pathogenesis of the two subtypes. METHODS: 20 patients with LAA cerebrovascular disease, 20 patients with age-related CSVD, 10 patients with Fabry disease and 14 controls were enrolled from October 2017 to January 2019. Ultra-high performance liquid chromatography-quadruple-time-of-flight mass spectrometry/mass spectrometry was used to determine sphingolipids. Univariate combined with multivariate analysis was used for comparison. Receiver operating characteristic curves were used to determine sensitivities and specificities. RESULTS: 276 sphingolipids were detected, including 39 Cer, 3 ceramide phosphates, 72 glycosphingolipids and 162 SM. (1) Cer (d36:3), Cer (d34:2), Cer (d38:6), Cer (d36:4) and Cer (d16:0/18:1) were increased in LAA; SM (d34:1), Cer (d34:2), Cer (d36:4), Cer (d16:0/18:1), Cer (d38:6), Cer (d36:3) and Cer (d32:0) were increased in age-related CSVD. (2) Cer (d36:4) and SM (d34:1) were increased in age-related CSVD compared with LAA. (3) Total trihexosyl ceramides were increased in Fabry group compared with control (P<0.05); SM (d34:1) was increased in Fabry group. CONCLUSIONS: Ceramides are increased in both LAA and age-related CSVD, which may be related to similar risk factors and pathophysiological process of arteriosclerosis; SM is increased in both age-related CSVD and Fabry disease, suggesting that increased SM may be associated with CSVD. Glycosphingolipids, trihexosylceramides in particular, are increased in Fabry disease.


Assuntos
Doenças de Pequenos Vasos Cerebrais/sangue , Arteriosclerose Intracraniana/sangue , Esfingolipídeos/sangue , Adulto , Idoso , Estudos de Casos e Controles , Ceramidas/sangue , Doença de Fabry/sangue , Feminino , Humanos , Lipidômica , Masculino , Pessoa de Meia-Idade , Esfingomielinas/sangue
19.
World Neurosurg ; 141: 327-330, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32593767

RESUMO

BACKGROUND: Extraventricular neurocytoma (EVN) is a rare neurocytoma occurring in the brain parenchyma outside the ventricular system that shares similar biological behaviors and histopathologic characteristics with central neurocytoma. Reports of EVN localized in the brainstem and cerebellum are relatively uncommon. In addition, few cases with radiotherapy as the only treatment have been reported and their outcomes were unclear. CASE DESCRIPTION: We report a case of pathologically confirmed EVN of the brainstem and cerebellum in a 43-year-old male who presented with unprovoked nausea and dizziness. The patient received radiotherapy only and showed a favorable outcome during the 2-year follow-up period. CONCLUSIONS: These results suggest that patients with EVN who are treated with radiotherapy without surgery may have a favorable prognosis.


Assuntos
Neoplasias Encefálicas/radioterapia , Cerebelo/cirurgia , Neurocitoma/radioterapia , Adulto , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patologia , Cerebelo/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Neurocitoma/diagnóstico , Radioterapia (Especialidade)/métodos , Resultado do Tratamento
20.
Biochem Biophys Res Commun ; 523(4): 887-893, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-31955887

RESUMO

pH-sensitive polyethylene glycol-conjugated urokinase nanogels (PEG-UK) is a new form of urokinase (UK) nanogels that could release UK at certain pH values. In our former study, we demonstrated that the pH value in the infarcted brain significantly declined to the level that could trigger the delivery of UK from PEG-UK. Thrombolysis is recommended as the first choice for ischemic stroke within the time window. However, it is common for the patients to miss the thrombolysis time window, which is one of the major causes of bad prognosis from ischemic stroke. It remains promising for seeking therapeutic approaches for ischemic stroke by investigating potential protective reagents delivered out of the usually thrombolysis time window. In this study, the protective effect of administration of PEG-UK outside the usual time window and the underlying mechanisms were investigated. PEG-UK was administrated 2 h and a half after ischemic stroke Delayed administration of PEG-UK significantly ameliorated the severity of neurological deficits of permanent middle cerebral occlusion (pMCAO) rats and reduced the infiltration of inflammatory cells and the concentration of interleukin 1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) in the brain tissues. The content of water and the leakage of Evans Blue (EB) in the PEG-UK group were also decreased. Maintenance of the expression of platelet-derived growth factor-C (PDGF-C) and inhibition of the upregulation of metalloproteinase proteins, low-density lipoprotein receptor-related protein (LRP), nuclear factor κB (NF-κB) p65 and cyclooxygenase-2 (Cox-2) were observed through western blotting and realtime PCR in the PEG-UK group. Besides, delayed administration of PEG-UK attenuated the up regulation of Caspase8 and Caspase9 and the cleavage of Caspase3 and poly (ADP-ribose) polymerase 1 (PARP1) in ischemic lesion sites. Moreover, PEG-UK treatment also inhibited the upregulation and phosphorylation of N-methyl-D-aspartic acid receptors (NMDARs), which has been revealed to play a vital role in mediating excito-neurotoxicity in ischemic stroke. In conclusion, through the inhibition of LRP/NF-κB/Cox-2 pathway, the Caspase cascade and activation of NMDARs, administration of PEG-UK outside the usual time window could still exert protective effects in pMCAO rats through the maintenance of the integrity of BBB and the inhibition of apoptosis and excito-neurotoxicity.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Nanogéis/química , Fármacos Neuroprotetores/uso terapêutico , Polietilenoglicóis/química , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Isquemia Encefálica/complicações , Caspases/metabolismo , Ciclo-Oxigenase 2/metabolismo , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Infarto da Artéria Cerebral Média/patologia , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Masculino , Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/metabolismo , Fármacos Neuroprotetores/farmacologia , Neurotoxinas/toxicidade , Fosforilação/efeitos dos fármacos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo , Transdução de Sinais/efeitos dos fármacos , Acidente Vascular Cerebral/complicações , Fatores de Tempo , Ativador de Plasminogênio Tipo Uroquinase/administração & dosagem , Ativador de Plasminogênio Tipo Uroquinase/farmacologia
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