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2.
Cancer Lett ; 587: 216702, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38336288

RESUMO

Resistance to trastuzumab and the poor efficacy of subsequent chemotherapy have become major challenges for HER2-positive gastric cancer (GC). As resistance evolves, tumor cells may acquire a new drug susceptibility profile, profoundly impacting the subsequent treatment selection and patient survival. However, the interplay between trastuzumab and other types of drugs in HER2-positive GC remains elusive. In our study, we utilized resistant cell lines and tissue specimens to map the drug susceptibility profile of trastuzumab-resistant GC, discovering that resistance to trastuzumab induces collateral resistance to commonly used chemotherapeutic agents. Additionally, patients with collateral resistance distinguished by a 13-gene scoring model in HER2-positive GC cohorts are predicted to have a poor prognosis and may be sensitive to cholesterol-lowering drugs. Mechanistically, endosomal cholesterol transport is further confirmed to enrich cholesterol in the plasma membrane, contributing to collateral resistance through the Hedgehog-ABCB1 axis. As a driver for cholesterol, Cdc42 is activated by the formation of the NPC1-TßRI-Cdc42 complex to facilitate endosomal cholesterol transport. We demonstrated that inhibiting Cdc42 activation with ZCL278 reduces cholesterol levels in the plasma membrane and reverses collateral resistance between trastuzumab and chemotherapy in vitro and in vivo. Collectively, our findings verify the phenomena and mechanism of collateral resistance between trastuzumab and chemotherapy, and propose a potential therapeutic target and strategy in the second-line treatment for trastuzumab-resistant HER2-positive GC.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Trastuzumab/farmacologia , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular Tumoral
3.
Genes Dis ; 11(3): 100988, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38292199

RESUMO

Osteosarcoma is a differentiation-deficient disease, and despite the unique advantages and great potential of differentiation therapy, there are only a few known differentiation inducers, and little research has been done on their targets. Cell differentiation is associated with an increase in mitochondrial content and activity. The metabolism of some tumor cells is characterized by impaired oxidative phosphorylation, as well as up-regulation of aerobic glycolysis and pentose phosphate pathways. Leucine-containing zipper and EF-hand transmembrane protein 1 (LETM1) is involved in the maintenance of mitochondrial morphology and is closely associated with tumorigenesis and progression, as well as cancer cell stemness. We found that MG63 and 143B osteosarcoma cells overexpress LETM1 and exhibit abnormalities in mitochondrial structure and function. Knockdown of LETM1 partially restored the mitochondrial structure and function, inhibited the pentose phosphate pathway, promoted oxidative phosphorylation, and led to osteogenic differentiation. It also inhibited spheroid cell formation, proliferation, migration, and invasion in an in vitro model. When LETM1 was knocked down in vivo, there was reduced tumor formation and lung metastasis. These data suggest that mitochondria are aberrant in LETM1-overexpressing osteosarcoma cells, and knockdown of LETM1 partially restores the mitochondrial structure and function, inhibits the pentose phosphate pathway, promotes oxidative phosphorylation, and increases osteogenic differentiation, thereby reducing malignant biological behavior of the cells.

4.
Fish Shellfish Immunol ; 145: 109302, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38128680

RESUMO

Feeding high-fat (HF) diets has been shown to cause hepatic and intestinal impairment in fish species, but the mode of action, especially the pathways involved in the intestine, has not been determined yet. In this study, the effects of resveratrol (RES) supplementation on the intestinal structure, microbial flora, and fat metabolism in red tilapia (Oreochromis niloticus) were determined. The results showed RES maintained the structural integrity of the intestine and significantly increased the number of goblet cells in the midgut. RES significantly induced interferon (IL)-1ß, IL-6, IL-10, and tumor necrosis factor (TNF)-α, serumal and fecal trimetlylamine oxide (TMAO) and lipopolysaccharides (LPS), intestinal acetic acid levels. However, the concentrations of bound bile acids increased in HF-fed red tilapia. Atp5fa1 and Pafah1b3 significantly increased, Pmt and Acss2 significantly decreased, respectively, with RES supplementation, which was alleviated and retained at the same level in the selisistat (EX527) group. While for transcriptome and proteomics results, RES was found to promote fatty acid ß-oxidation and arachidonic acid metabolism associated with the peroxisome proliferator-activated receptor (PPAR) signaling pathway. The next validation experiment showed some genes related to apoptosis and fatty acid metabolism pathways were altered by RES supplementation. Namely, sn6, loc100702698, new_14481, and prkaa1 were upregulated, while ffrs1, ap3s1, and loc100705861 were downregulated. RES significantly increased Planctomycetes and Verrucomicrobia while decreased Moonvirus, Citrobacter, and Pseudomonas. Akkermansia and Fusobacterium significantly increased and Aeromonas significantly decreased. Thus, unsaturated fatty acid biosynthesis significantly increased and carbohydrate/energy metabolism decreased. To conclude, RES enabled the body to complete fatty acid ß-oxidation and arachidonic acid metabolism, whereas the addition of inhibitors increased the expression of the phagosome transcriptome and reduced fatty acid ß-oxidative metabolism.


Assuntos
Ciclídeos , Tilápia , Animais , Tilápia/metabolismo , Ciclídeos/metabolismo , Dieta Hiperlipídica , Resveratrol/metabolismo , Metabolismo dos Lipídeos , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/farmacologia , Intestinos , Transdução de Sinais , Ácidos Graxos/metabolismo , Ácidos Araquidônicos/metabolismo , Ácidos Araquidônicos/farmacologia , Dieta , Suplementos Nutricionais , Ração Animal/análise
5.
Neuroepidemiology ; 57(6): 413-422, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37734325

RESUMO

INTRODUCTION: Cerebral small vessel disease (CSVD) is a significant burden of morbidity and mortality among elderly people around the world. Epidemiological data with complete CSVD evaluations and a large sample size in the general population are still limited. METHODS: Community-dwelling residents in Lishui city in China from the cross-sectional survey of the Polyvascular Evaluation for Cognitive Impairment and Vascular Events (PRECISE) study were included in this study from 2017 to 2019. All participants underwent 3 Tesla brain magnetic resonance images to assess CSVD imaging markers. Demographic and risk factor data were collected. The general and age-specific prevalence of lacune, confluent white matter hyperintensity (WMH), moderate-severe enlarged perivascular spaces (EPVS), cerebral microbleed (CMB), and total CSVD score (an ordinal scale from 0 to 4, counting the presence of four imaging markers of CSVD) was evaluated. Associations between vascular risk factors and these markers were analyzed by multivariable logistic regression. RESULTS: A total of 3,063 participants were enrolled. The mean age was 61.2 years and 46.5% were men. The most prevalent CSVD marker was confluent WMH (16.7%), followed by CMB (10.2%), moderate-severe EPVS in the basal ganglia (BG-EPVS) (9.8%), and lacune (5.6%). 30.5% of the participants have at least one of the four markers (total CSVD score ≥1 points). The prevalence of CSVD markers increases as age increases. Age and hypertension were independent risk factors for four CSVD markers and the total CSVD score. CONCLUSIONS: In this Chinese cohort with community-based adults aged 50-75 years, our findings showed a prevalence of 30.5% for CSVD. The most prevalent CSVD marker was confluent WMH, followed by CMB, moderate-severe BG-EPVS, and lacune. The risk factors for CSVD must be strictly screened and controlled in adults living in the community.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Masculino , Idoso , Adulto , Humanos , Pessoa de Meia-Idade , Feminino , Prevalência , Estudos Transversais , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/epidemiologia , Encéfalo , Imageamento por Ressonância Magnética , Fatores de Risco
6.
Neurol Ther ; 12(5): 1745-1758, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37490234

RESUMO

INTRODUCTION: Similar white matter hyperintensities (WMH) burden may have varied cognitive outcomes in patients with cerebral small vessel disease (CSVD). This study aimed to evaluate whether blood-brain barrier (BBB) permeability is associated with cognitive impairment (CI) heterogeneity in patients with WMH. METHODS: We recruited 51 participants with WMH. We evaluated WMH burden using the Fazekas scale and WMH volume on structural magnetic resonance imaging (MRI), and assessed BBB permeability using dynamic contrast-enhanced (DCE)-MRI. We used permeability-surface area product (PS) from the Patlak model to represent BBB permeability. All patients underwent Mini-Mental State Examination (MMSE), Boston Naming Test (BNT) and animal verbal fluency test (VFT) for cognitive assessment. We divided patients into CI and non-CI groups based on their MMSE scores (< 27 or ≥ 27) and used multiple linear regression models to investigate the associations between MRI parameters and cognitive function. RESULTS: Patients in the two groups did not differ in Fazekas scores and WMH volume. However, patients in the CI group showed significantly higher PS in the WMH regions than those in non-CI group (1.89 × 10-3 versus 1.00 × 10-3, p = 0.032 in periventricular WMH [PVWMH]; 1.27 × 10-3 versus 0.74 × 10-3, p = 0.043 in deep WMH [DWMH]), indicating the breakdown of BBB in the CI group. In all patients with WMH, increased BBB permeability in PVWMH and DWMH was significantly associated with lower cognitive and language function after adjustment for age, education level (EL) and intracranial volume (ICV). In the CI group, this correlation remained significant. WMH volume was not associated with cognitive performance in either all patients or those with CI. CONCLUSION: BBB impairment might be a more sensitive indicator for cognitive and language dysfunction than WMH volume in patients with WMH and possibly explains the heterogeneity of cognitive performance in patients with similar WMH burden.

7.
Biochem Pharmacol ; 214: 115666, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37391086

RESUMO

The dysregulation of Wnt/ß-catenin signaling pathway is closely related to tumorigenesis, metastasis and cancer stem cell maintenance. Salinomycin is a polyether ionophore antibiotic that selectively eliminates cancer stem cells by inhibiting the Wnt/ß-catenin signal pathway. Salinomycin selectively target cancer stem cells, but the toxicity limits its further use. In this study, we explore the anti-tumor mechanism of one most active salinomycin C20-O-alkyl oximederivative SAL-98 and found that SAL-98 exerts 10 times higher anti-tumor and anti-CSCs activities compared with salinomycin, which induces cell cycle arrest, ER stress and mitochondria dysfunction and inhibits Wnt/ß-catenin signal pathway in vitro with high efficacy. Moreover, SAL-98 shows good anti-metastasis effect in vivo. In addition, SAL-98 demonstrates same anti-tumor activities as salinomycin with less 5 times concentration in vivo, the ER stress, autophagy and anti-CSCs effects were also confirmed in vivo. Mechanistically, SAL-98 inhibits the Wnt/ß-catenin signaling pathway associated with CHOP expression induced by ER stress, the induced CHOP disrupts the ß-catenin/TCF4 complex and represses the Wnt targeted genes. This study provides an alternative strategy for rational drug development to target Wnt/ß-catenin signaling pathway.


Assuntos
Via de Sinalização Wnt , beta Catenina , beta Catenina/metabolismo , Proliferação de Células , Linhagem Celular Tumoral , Células-Tronco Neoplásicas
8.
Front Immunol ; 14: 1338918, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38288125

RESUMO

Inflammatory bowel disease (IBD), characterized primarily by gastrointestinal inflammation, predominantly manifests as Crohn's disease (CD) and ulcerative colitis (UC). It is acknowledged that Inflammation plays a significant role in cancer development and patients with IBD have an increased risk of various cancers. The progression from inflammation to carcinogenesis in IBD is a result of the interplay between immune cells, gut microbiota, and carcinogenic signaling pathways in epithelial cells. Long-term chronic inflammation can lead to the accumulation of mutations in epithelial cells and the abnormal activation of carcinogenic signaling pathways. Furthermore, Immune cells play a pivotal role in both the acute and chronic phases of IBD, contributing to the transformation from inflammation to tumorigenesis. And patients with IBD frequently exhibit dysbiosis of the intestinal microbiome. Disruption of the gut microbiota and subsequent immune dysregulation are central to the pathogenesis of both IBD and colitis associated colorectal cancer (CAC). The proactive management of inflammation combined with regular endoscopic and tumor screenings represents the most direct and effective strategy to prevent the IBD-associated cancer.


Assuntos
Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Neoplasias , Humanos , Doenças Inflamatórias Intestinais/complicações , Inflamação/complicações , Transdução de Sinais
9.
Artigo em Inglês | MEDLINE | ID: mdl-35820615

RESUMO

Resveratrol (RES), as a polyphenol natural plant extract, mainly accumulates in the root of Polygonum cuspidatum, which can alleviate liver injury in mammals. Our study aims to explore the effects and potential mechanism of RES on lipid metabolism of red tilapia, and the effects of RES on liver structure, fat synthesis and metabolism of red tilapia were determined. The present study designed four groups named as 8 % fat (8%CK), 10 % fat (10 % HF), 10 % HF + RES and 10 % HF + RES + EX527 (selisistat). The liver tissues of red tilapia were collected at 3 (3 W), 6 (6 W) and 9 (9 W) weeks for parameter determination. Compared to the normal diet group, the hepatocyte of tilapia showed nuclear shift and vacuoles of different sizes when fed a high-fat diet. Meanwhile, the high-fat diet increased the contents of LDL, TC and TG significantly at 6 W, and significantly decreased the content of NAD+ at 9 W. Compared to the high-fat group, the nuclei of tilapia fed with RES were increased and visible, the degree of steatosis and the number of vacuoles were both reduced. At 3/6/9 W, RES significantly decreased the contents of LDL, TG and TMAO, and significantly increased the content of NAD+. A total of 1416 genes were up-regulated and 1928 genes were down-regulated in the group with added RES when compared to the 10 % HF group. The pathways related to lipid metabolism including PPAR signaling pathway have been enriched. Interestingly, the expressions of sirt1, pparα, fabp7 and cpt1b genes were up-regulated in RES diet group, while the expressions of pparγ, me1, scd and lpl genes were down-regulated. After the addition of an inhibitor (EX527), the above indexes showed an opposite trend when compared to the group with added RES. The overall results showed that the high-fat diet could cause fatty liver lesions in the liver of red tilapia, and RES could activate the sirt1 gene, regulate the PPARα/γ pathway and related genes, and thus regulate liver fat synthesis and metabolism leading to the alleviation of damage to liver tissue.


Assuntos
Ciclídeos , Tilápia , Animais , Ciclídeos/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Mamíferos/metabolismo , NAD/metabolismo , PPAR alfa/metabolismo , Resveratrol/farmacologia , Sirtuína 1/genética , Sirtuína 1/metabolismo
10.
Stroke ; 53(1): 29-33, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34847709

RESUMO

BACKGROUND AND PURPOSE: Cerebral small vessel disease-a major cause of stroke and dementia-is associated with cerebrovascular dysfunction. We investigated whether short-term isosorbide mononitrate (ISMN) and cilostazol, alone or in combination, improved magnetic resonance imaging-measured cerebrovascular function in patients with lacunar ischemic stroke. METHODS: Participants were randomized to ISMN alone, cilostazol alone, both ISMN and cilostazol, or no medication. Participants underwent structural, cerebrovascular reactivity (to 6% carbon dioxide) and phase-contrast pulsatility magnetic resonance imaging at baseline and after 8 weeks of medication. RESULTS: Of 27 participants (mean age, 68±7.7; 44% female), 22 completed cerebrovascular reactivity and pulsatility imaging with complete datasets. White matter cerebrovascular reactivity increased in the ISMN (ß=0.021%/mm Hg [95% CI, 0.003-0.040]) and cilostazol (ß=0.035%/mm Hg [95% CI, 0.014-0.056]) monotherapy groups and in those taking any versus no medication (ß=0.021%/mm Hg [95% CI, 0.005-0.037]). CONCLUSIONS: While limited by small sample size, we demonstrate that measuring cerebrovascular function with magnetic resonance imaging is feasible in clinical trials and that ISMN and cilostazol may improve cerebrovascular function. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02481323. URL: www.isrctn.com; Unique identifier: ISRCTN12580546. URL: www.clinicaltrialsregister.eu; Unique identifier: EudraCT 2015-001953-33.


Assuntos
Doenças de Pequenos Vasos Cerebrais/tratamento farmacológico , Cilostazol/uso terapêutico , Hemodinâmica/efeitos dos fármacos , Dinitrato de Isossorbida/análogos & derivados , Lipoproteínas/uso terapêutico , Vasodilatadores/uso terapêutico , Idoso , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/fisiopatologia , Cilostazol/farmacologia , Feminino , Hemodinâmica/fisiologia , Humanos , Dinitrato de Isossorbida/farmacologia , Dinitrato de Isossorbida/uso terapêutico , Lipoproteínas/farmacologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Vasodilatadores/farmacologia
11.
Cancer Immunol Res ; 10(2): 182-199, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34933913

RESUMO

Metastatic microsatellite-stable (MSS) colorectal cancer rarely responds to immune checkpoint inhibitors (ICI). Metabolism heterogeneity in the tumor microenvironment (TME) presents obstacles to antitumor immune response. Combining transcriptome (The Cancer Genome Atlas MSS colorectal cancer, n = 383) and digital pathology (n = 96) analysis, we demonstrated a stroma metabolism-immune excluded subtype with poor prognosis in MSS colorectal cancer, which could be attributed to interaction between chondroitin-6-sulfate (C-6-S) metabolites and M2 macrophages, forming the "exclusion barrier" in the invasive margin. Furthermore, C-6-S derived from cancer-associated fibroblasts promoted co-nuclear translocation of pSTAT3 and GLI1, activating the JAK/STAT3 and Hedgehog pathways. In vivo experiments with C-6-S-targeted strategies decreased M2 macrophages and reprogrammed the immunosuppressive TME, leading to enhanced response to anti-PD-1 in MSS colorectal cancer. Therefore, C-6-S-induced immune exclusion represents an "immunometabolic checkpoint" that can be exploited for the application of combination strategies in MSS colorectal cancer ICI treatment.


Assuntos
Sulfatos de Condroitina , Neoplasias Colorretais , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Proteínas Hedgehog/genética , Humanos , Repetições de Microssatélites , Sulfatos , Microambiente Tumoral
12.
Front Physiol ; 12: 644837, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149442

RESUMO

BACKGROUND: Cerebrovascular reactivity (CVR) measures blood flow change in response to a vasoactive stimulus. Impairment is associated with several neurological conditions and can be measured using blood oxygen level-dependent (BOLD) magnetic resonance imaging (MRI). Field strength affects the BOLD signal, but the effect on CVR is unquantified in patient populations. METHODS: We recruited patients with minor ischemic stroke and assessed CVR magnitude and delay time at 3 and 1.5 Tesla using BOLD MRI during a hypercapnic challenge. We assessed subcortical gray (GM) and white matter (WM) differences using Wilcoxon signed rank tests and scatterplots. Additionally, we explored associations with demographic factors, WM hyperintensity burden, and small vessel disease score. RESULTS: Eighteen of twenty patients provided usable data. At 3T vs. 1.5T: mean CVR magnitude showed less variance (WM 3T: 0.062 ± 0.018%/mmHg, range 0.035, 0.093; 1.5T: 0.057 ± 0.024%/mmHg, range 0.016, 0.094) but was not systematically higher (Wilcoxon signal rank tests, WM: r = -0.33, confidence interval (CI): -0.013, 0.003, p = 0.167); delay showed similar variance (WM 3T: 40 ± 12 s, range: 12, 56; 1.5T: 31 ± 13 s, range 6, 50) and was shorter in GM (r = 0.33, CI: -2, 9, p = 0.164) and longer in WM (r = -0.59, CI: -16, -2, p = 0.010). Patients with higher disease severity tended to have lower CVR at 1.5 and 3T. CONCLUSION: Mean CVR magnitude at 3T was similar to 1.5T but showed less variance. GM/WM delay differences may be affected by low signal-to-noise ratio among other factors. Although 3T may reduce variance in CVR magnitude, CVR is readily assessable at 1.5T and reveals comparable associations and trends with disease severity.

13.
Front Neurol ; 12: 647848, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017302

RESUMO

Cerebral small vessel disease (SVD) is a major contributor to stroke and dementia, characterized by white matter hyperintensities (WMH) on neuroimaging. WMH are associated with reduced cerebral blood flow (CBF) cross-sectionally, though longitudinal associations remain unclear. We updated a 2016 systematic review, identifying 30 new studies, 27 cross-sectional (n = 2,956) and 3 longitudinal (n = 440). Cross-sectionally, 10/27 new studies (n = 1,019) included sufficient data for meta-analysis, which we meta-analyzed with 24 previously reported studies (n = 1,161), total 34 (n = 2,180). Our meta-analysis showed that patients with lower CBF had worse WMH burden (mean global CBF: standardized mean difference (SMD): -0.45, 95% confidence interval (CI): -0.64, -0.27). Longitudinally, associations between baseline CBF and WMH progression varied: the largest study (5 years, n = 252) found no associations, while another small study (4.5 years, n = 52) found that low CBF in the periventricular WMH penumbra predicted WMH progression. We could not meta-analyse longitudinal studies due to different statistical and methodological approaches. We found that CBF was lower in WMH than in normal-appearing white matter in an additional meta-analysis (5 cross-sectional studies; n = 295; SMD: -1.51, 95% CI: -1.94, -1.07). These findings highlight that relationships between resting CBF and WMH are complex. Further longitudinal studies analyzing regional CBF and subsequent WMH change are required to determine the role of CBF in SVD progression.

14.
Neurology ; 94(21): e2258-e2269, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32366534

RESUMO

OBJECTIVE: To investigate cerebrovascular reactivity (CVR), blood flow, vascular and CSF pulsatility, and their independent relationship with cerebral small vessel disease (SVD) features in patients with minor ischemic stroke and MRI evidence of SVD. METHODS: We recruited patients with minor ischemic stroke and assessed CVR using blood oxygen level-dependent MRI during a hypercapnic challenge, cerebral blood flow (CBF), vascular and CSF pulsatility using phase-contrast MRI, and structural magnetic resonance brain imaging to quantify white matter hyperintensities (WMHs) and perivascular spaces (PVSs). We used multiple regression to identify parameters associated with SVD features, controlling for patient characteristics. RESULTS: Fifty-three of 60 patients completed the study with a full data set (age 68.0% ± 8.8 years, 74% male, 75% hypertensive). After controlling for age, sex, and systolic blood pressure, lower white matter CVR was associated with higher WMH volume (-0.01%/mm Hg per log10 increase in WMH volume, p = 0.02), basal ganglia PVS (-0.01%/mm Hg per point increase in the PVS score, p = 0.02), and higher venous pulsatility (superior sagittal sinus -0.03%/mm Hg, p = 0.02, per unit increase in the pulsatility index) but not with CBF (p = 0.58). Lower foramen magnum CSF stroke volume was associated with worse white matter CVR (0.04%/mm Hg per mL increase in stroke volume, p = 0.04) and more severe basal ganglia PVS (p = 0.09). CONCLUSIONS: Lower CVR, higher venous pulsatility, and lower foramen magnum CSF stroke volume indicate that dynamic vascular dysfunctions underpin PVS dysfunction and WMH development. Further exploration of microvascular dysfunction and CSF dynamics may uncover new mechanisms and intervention targets to reduce SVD lesion development, cognitive decline, and stroke.


Assuntos
Encéfalo/irrigação sanguínea , Doenças de Pequenos Vasos Cerebrais/fisiopatologia , Circulação Cerebrovascular/fisiologia , Hemodinâmica/fisiologia , Idoso , Encéfalo/patologia , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/patologia , Líquido Cefalorraquidiano/fisiologia , Feminino , Sistema Glinfático/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia , Substância Branca/patologia
15.
Mater Sci Eng C Mater Biol Appl ; 112: 110894, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32409049

RESUMO

A novel Nb/NiTi superelastic composite with a shell-core structure was designed and fabricated to achieve a combination of biocompatibility and superelasticity (large recoverable strain ε accompanied by high critical stress for inducing martensitic transformation σSIM). The good biocompatibility is mainly attributed to the outer non-cytotoxic Nb shell that prevents inner NiTi core from direct contact with cells. Meanwhile, the inner NiTi core endows the composite with superelasticity through a fully reversible stress-induced martensitic transformation between B2 parent phase and B19' martensite. These results might shed some light on design and development of novel superelastic composites for biomedical applications.


Assuntos
Materiais Biocompatíveis/química , Níquel/química , Nióbio/química , Titânio/química , Animais , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ligas Dentárias/química , Ligas Dentárias/farmacologia , Elasticidade , Camundongos , Resistência à Tração , Raios Ultravioleta
16.
J Cereb Blood Flow Metab ; 40(1): 85-99, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30295558

RESUMO

Cerebral small vessel disease (SVD) contributes to 25% of ischemic strokes and 45% of dementias. We aimed to investigate the role of cerebral blood flow (CBF) and intracranial pulsatility in SVD. We scanned 60 patients with minor ischemic stroke, representing a range of white matter hyperintensities (WMH). We rated WMH and perivascular spaces (PVS) using semi-quantitative scales and measured WMH volume. We measured flow and pulsatility in the main cerebral vessels and cerebrospinal fluid (CSF) using phase-contrast MRI. We investigated the association between flow, pulsatility and SVD features. In 56/60 patients (40 male, 67.8±8.3 years) with complete data, median WMH volume was 10.7 mL (range 1.4-75.0 mL), representing median 0.77% (0.11-5.17%) of intracranial volume. Greater pulsatility index (PI) in venous sinuses was associated with larger WMH volume (e.g. superior sagittal sinus, ß = 1.29, P < 0.01) and more basal ganglia PVS (e.g. odds ratio = 1.38, 95% confidence interval 1.06, 1.79, per 0.1 increase in superior sagittal sinus PI) independently of age, sex and blood pressure. CSF pulsatility and CBF were not associated with SVD features. Our results support a close association of SVD features with increased intracranial pulsatility rather than with low global CBF, and provide potential targets for mechanistic research, treatment and prevention of SVD.


Assuntos
Doenças de Pequenos Vasos Cerebrais/fisiopatologia , Circulação Cerebrovascular , Fluxo Pulsátil , Idoso , Gânglios da Base/irrigação sanguínea , Cavidades Cranianas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Seio Sagital Superior
17.
EClinicalMedicine ; 11: 34-43, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31317131

RESUMO

BACKGROUND: Lacunar stroke, a frequent clinical manifestation of small vessel disease (SVD), differs pathologically from other ischaemic stroke subtypes and has no specific long-term secondary prevention. Licenced drugs, isosorbide mononitrate (ISMN) and cilostazol, have relevant actions to prevent SVD progression. METHODS: We recruited independent patients with clinically confirmed lacunar ischaemic stroke without cognitive impairment to a prospective randomised clinical trial, LACunar Intervention-1 (LACI-1). We randomised patients using a central web-based system, 1:1:1:1 with minimisation, to masked ISMN 25 mg bd, cilostazol 100 mg bd, both ISMN and cilostazol started immediately, or both with start delayed. We escalated doses to target over two weeks, sustained for eight weeks. Primary outcome was the proportion achieving target dose. Secondary outcomes included symptoms, safety (haemorrhage, recurrent vascular events), cognition, haematology, vascular function, and neuroimaging. LACI-1 was powered (80%, alpha 0.05) to detect 35% (90% versus 55%) difference between the proportion reaching target dose on one versus both drugs at 55 patients. Registration ISRCTN12580546. FINDINGS: LACI-1 enrolled 57 participants between March 2016 and August 2017: 18 (32%) females, mean age 66 (SD 11, range 40-85) years, onset-randomisation 203 (range 6-920) days. Most achieved full (64%) or over half (87%) dose, with no difference between cilostazol vs ISMN, single vs dual drugs. Headache and palpitations increased initially then declined similarly with dual versus single drugs. There was no between-group difference in BP, pulse-wave velocity, haemoglobin or platelet function, but pulse rate was higher (mean difference, MD, 6.4, 95%CI 1.2-11.7, p = 0.02), platelet count higher (MD 35.7, 95%CI 2.8, 68.7, p = 0.03) and white matter hyperintensities reduced more (Chi-square p = 0.007) with cilostazol versus no cilostazol. INTERPRETATION: Cilostazol and ISMN are well tolerated when the dose is escalated, without safety concerns, in patients with lacunar stroke. Larger trials with longer term follow-up are justified. FUNDING: Alzheimer's Society (AS-PG-14-033).

18.
Oncotarget ; 10(35): 3267-3275, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31143372

RESUMO

The global outputs of annual publication in long non-coding RNAs (lncRNAs) and chemotherapeutic resistance research exponentially increased from 2 in 2008 to 176 in 2017. Using Java application CiteSpace V and VOSviewer, this study assessed the publication model of lncRNAs and chemoresistance by bibliometric analysis. Totally, 2883 authors contributed 528 publications of lncRNAs and chemoresistance in 215 academic journals in the recent decade (2008-2018). Oncotarget in the 215 academic journals published the highest number of publications (60). China had the highest number of publication outputs (358). The leading institute was Nanjing Medical University. Wang Y was the most influential author (13 counts). Gupta RA had the most cited documents (87 counts). "Gene expression" and "poor prognosis" were identified as the hotspots. "Cancer stem cell", "HOTAIR" and "UCA1" were the frontiers of the fields in recent years. The increase of publications on lncRNAs and chemotherapeutic resistance will continue in the next years. HOTAIR and UCA1 with multiple roles in drug resistance may offer big opportunities for targeted chemoresistance in cancer therapy. These results may help us discover and explain the possible underlying laws of the subject.

19.
Int J Stroke ; 13(2): 195-206, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28933655

RESUMO

Background Impaired autoregulation may contribute to the pathogenesis of cerebral small vessel disease. Reliable protocols for measuring microvascular reactivity are required to test this hypothesis and for providing secondary endpoints in clinical trials. Aims To develop and assess a protocol for acquisition and processing of cerebrovascular reactivity by MRI, in subcortical tissue of patients with small vessel disease and minor stroke. Methods We recruited 15 healthy volunteers, testing paradigms using 1- and 3-min 6% CO2 challenges with repeat scanning, and 15 patients with history of minor stroke. We developed a protocol to measure cerebrovascular reactivity and delay times, assessing tolerability and reproducibility in grey and white matter areas. Results The 3-min paradigm yielded more reproducible data than the 1-min paradigm (CV respectively: 7.9-15.4% and 11.7-70.2% for cerebrovascular reactivity in grey matter), and was less reproducible in white matter (16.1-24.4% and 27.5-141.0%). Tolerability was similar for the two paradigms, but mean cerebrovascular reactivity and cerebrovascular reactivity delay were significantly higher for the 3-min paradigm in most regions. Patient tolerability was high with no evidence of greater failure rate (1/15 patients vs. 2/15 volunteers withdrew at the first visit). Grey matter cerebrovascular reactivity was lower in patients than in volunteers (0.110-0.234 vs. 0.172-0.313%/mmHg; p < 0.05 in 6/8 regions), as was the white matter cerebrovascular reactivity delay (16.2-43.9 vs. 31.1-47.9 s; p < 0.05 in 4/8 regions). Conclusions An effective and well-tolerated protocol for measurement of cerebrovascular reactivity was developed for use in ongoing and future trials to investigate small vessel disease pathophysiology and to measure treatment effects.


Assuntos
Doenças de Pequenos Vasos Cerebrais/diagnóstico , Imageamento por Ressonância Magnética/métodos , Microvasos/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico , Substância Branca/diagnóstico por imagem , Adulto , Circulação Cerebrovascular , Feminino , Substância Cinzenta/irrigação sanguínea , Substância Cinzenta/diagnóstico por imagem , Voluntários Saudáveis , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Microvasos/patologia , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Substância Branca/irrigação sanguínea , Adulto Jovem
20.
Int J Stroke ; 13(5): 530-538, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28906205

RESUMO

Rationale The pathophysiology of most lacunar stroke, a form of small vessel disease, is thought to differ from large artery atherothrombo- or cardio-embolic stroke. Licensed drugs, isosorbide mononitrate and cilostazol, have promising mechanisms of action to support their testing to prevent stroke recurrence, cognitive impairment, or radiological progression after lacunar stroke. Aim LACI-1 will assess the tolerability, safety, and efficacy, by dose, of isosorbide mononitrate and cilostazol, alone and in combination, in patients with ischemic lacunar stroke. Sample size A sample of 60 provides 80+% power (significance 0.05) to detect a difference of 35% (90% versus 55%) between those reaching target dose on one versus both drugs. Methods and design LACI-1 is a phase IIa partial factorial, dose-escalation, prospective, randomized, open label, blinded endpoint trial. Participants are randomized to isosorbide mononitrate and/or cilostazol for 11 weeks with dose escalation to target as tolerated in two centers (Edinburgh, Nottingham). At three visits, tolerability, safety, blood pressure, pulse wave velocity, and platelet function are assessed, plus magnetic resonance imaging to assess cerebrovascular reactivity in a subgroup. Study outcomes Primary: proportion of patients completing study achieving target maximum dose. Secondary symptoms whilst taking medications; safety (hemorrhage, recurrent vascular events, falls); blood pressure, platelet function, arterial stiffness, and cerebrovascular reactivity. Discussion This study will inform the design of a larger phase III trial of isosorbide mononitrate and cilostazol in lacunar stroke, whilst providing data on the drugs' effects on vascular and platelet function. Trial registration ISRCTN (ISRCTN12580546) and EudraCT (2015-001953-33).


Assuntos
Cilostazol/uso terapêutico , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/prevenção & controle , Demência/prevenção & controle , Dinitrato de Isossorbida/análogos & derivados , Vasodilatadores/uso terapêutico , Fatores Etários , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/tratamento farmacológico , Demência/etiologia , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Dinitrato de Isossorbida/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Índice de Gravidade de Doença , Resultado do Tratamento , Reino Unido
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