Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 123
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Anal Chem ; 96(8): 3445-3453, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38364860

RESUMO

Slow-light photonic crystal waveguide (PCW) gas sensors based on infrared absorption spectroscopy play a pivotal role in enhancing the on-chip interaction between light and gas molecules, thereby significantly boosting sensor sensitivity. However, two-dimensional (2D) PCWs are limited by their narrow mode bandwidth and susceptibility to polarization, which restricts their ability for multigas measurement. Due to quasi-TE and quasi-TM mode guiding characteristics in one-dimensional (1D) PCW, a novel slow-light-enhanced polarization division multiplexing infrared absorption spectroscopy was proposed for on-chip wideband multigas detection. The optimized 1D PCW gas sensor experimentally shows an impressive slow-light mode bandwidth exceeding 100 nm (TM, 1500-1550 nm; TE, 1610-1660 nm) with a group index ranging from 4 to 25 for the two polarizations. The achieved bandwidth in the 1D PCW is 2-3 times that of the reported quasi-TE polarized 2D PCWs. By targeting the absorption lines of different gas species, multigas detection can be realized by modulating the lasers and demodulating the absorption signals at different frequencies. As an example, we performed dual-gas measurements with the 1D PCW sensor operating in TE mode at 1.65 µm for methane (CH4) detection and in TM mode at 1.53 µm for acetylene (C2H2) detection. The 1 mm long sensor achieved a remarkable limit of detection (LoD) of 0.055% for CH4 with an averaging time of 17.6 s, while for C2H2, the LoD was 0.18%. This polarization multiplexing sensor shows great potential for on-chip gas measurement because of the slow-light enhancement in the light-gas interaction effect as well as the large slow-light bandwidth for multigas detection.

2.
Int J Obes (Lond) ; 48(7): 913-922, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38374247

RESUMO

BACKGROUND: Asprosin (ASP) is a newly discovered adipokine secreted by white adipose tissue (WAT), which can regulate the homeostasis of glucose and lipid metabolism. However, it is not clear whether it can regulate the browning of WAT and mitophagy during the browning process. Accordingly, this study aims to investigate the effects and possible mechanisms of ASP on the browning of WAT and mitophagy in vivo and in vitro. METHODS: In in vivo experiments, some mouse models were used including adipose tissue ASP-specific deficiency (ASP-/-), high fat diet (HFD)-induced obesity and white adipose browning; in in vitro experiments, some cell models were also established and used, including ASP-deficient 3T3-L1 preadipocyte (ASP-/-) and CL-316243 (CL, 1 µM)-induced browning. Based on these models, the browning of WAT and mitophagy were evaluated by morphology, functionality and molecular markers. RESULTS: Our in vivo data show that adipose tissue-specific deletion of ASP contributes to weight loss in mice; supplementation of ASP inhibits the expressions of browning-related proteins including UCP1, PRDM16 and PGC1ɑ during the cold exposure-induced browning, and promotes the expressions of mitophagy-related proteins including PINK1 and Parkin under the conditions of whether normal diet (ND) or HFD. Similarly, our in vitro data also show that the deletion of ASP in 3T3-L1 cells significantly increases the expressions of the browning-related proteins and decreases the expressions of the mitophagy-related proteins. CONCLUSIONS: These data demonstrate that ASP deletion can facilitate the browning and inhibit mitophagy in WAT. The findings will lay an experimental foundation for the development of new drugs targeting ASP and the clinical treatment of metabolic diseases related to obesity.


Assuntos
Tecido Adiposo Marrom , Tecido Adiposo Branco , Mitofagia , Obesidade , Animais , Camundongos , Mitofagia/fisiologia , Obesidade/metabolismo , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Marrom/metabolismo , Dieta Hiperlipídica , Masculino , Células 3T3-L1 , Camundongos Endogâmicos C57BL , Adipócitos/metabolismo , Modelos Animais de Doenças
3.
Opt Lett ; 49(2): 190-193, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38194525

RESUMO

Compared to the most commonly used on-chip direct absorption spectroscopy (DAS) gas detection technique, the second harmonic (2f) based on-chip wavelength modulation spectroscopy (WMS) proposed by our group has the faculty to suppress noise and improve performance, but the accuracy of 2f WMS is easily affected by optical power variation. A mid-infrared auto-correction on-chip gas sensor based on 2f/1f WMS was proposed for decreasing the influence of the variation of optical power. The limit of detection of methane (CH4) obtained by a chalcogenide waveguide with a length of 10 mm is 0.031%. Compared with the 2f WMS, the maximum relative concentration error of the auto-correction on-chip gas sensor was decreased by ∼5.6 times. The measurement error is ≤2% in a temperature variation range of 30°C. This auto-correction sensor without a complicated manual calibration is helpful to the high accuracy measurement for on-chip integrated gas sensing.

4.
Circ Res ; 130(7): 1038-1055, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35196865

RESUMO

BACKGROUND: The transcription factor BACH1 (BTB and CNC homology 1) suppressed endothelial cells (ECs) proliferation and migration and impaired angiogenesis in the ischemic hindlimbs of adult mice. However, the role and underlying mechanisms of BACH1 in atherosclerosis remain unclear. METHODS: Mouse models of atherosclerosis in endothelial cell (EC)-specific-Bach1 knockout mice were used to study the role of BACH1 in the regulation of atherogenesis and the underlying mechanisms. RESULTS: Genetic analyses revealed that coronary artery disease-associated risk variant rs2832227 was associated with BACH1 gene expression in carotid plaques from patients. BACH1 was upregulated in ECs of human and mouse atherosclerotic plaques. Endothelial Bach1 deficiency decreased turbulent blood flow- or western diet-induced atherosclerotic lesions, macrophage content in plaques, expression of endothelial adhesion molecules (ICAM1 [intercellular cell adhesion molecule-1] and VCAM1 [vascular cell adhesion molecule-1]), and reduced plasma TNF-α (tumor necrosis factor-α) and IL-1ß levels in atherosclerotic mice. BACH1 deletion or knockdown inhibited monocyte-endothelial adhesion and reduced oscillatory shear stress or TNF-α-mediated induction of endothelial adhesion molecules and/or proinflammatory cytokines in mouse ECs, human umbilical vein ECs, and human aortic ECs. Mechanistic studies showed that upon oscillatory shear stress or TNF-α stimulation, BACH1 and YAP (yes-associated protein) were induced and translocated into the nucleus in ECs. BACH1 upregulated YAP expression by binding to the YAP promoter. BACH1 formed a complex with YAP inducing the transcription of adhesion molecules. YAP overexpression in ECs counteracted the antiatherosclerotic effect mediated by Bach1-deletion in mice. Rosuvastatin inhibited BACH1 expression by upregulating microRNA let-7a in ECs, and decreased Bach1 expression in the vascular endothelium of hyperlipidemic mice. BACH1 was colocalized with YAP, and the expression of BACH1 was positively correlated with YAP and proinflammatory genes, as well as adhesion molecules in human atherosclerotic plaques. CONCLUSIONS: These data identify BACH1 as a mechanosensor of hemodynamic stress and reveal that the BACH1-YAP transcriptional network is essential to vascular inflammation and atherogenesis. BACH1 shows potential as a novel therapeutic target in atherosclerosis.


Assuntos
Aterosclerose , Placa Aterosclerótica , Animais , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/prevenção & controle , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Placa Aterosclerótica/patologia , Fatores de Transcrição/metabolismo
5.
J Neuroinflammation ; 19(1): 315, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36577999

RESUMO

BACKGROUND: Dysregulated activation of the inflammasome is involved in various human diseases including acute cerebral ischemia, multiple sclerosis and sepsis. Though many inflammasome inhibitors targeting NOD-like receptor protein 3 (NLRP3) have been designed and developed, none of the inhibitors are clinically available. Growing evidence suggests that targeting apoptosis-associated speck-like protein containing a CARD (ASC), the oligomerization of which is the key event for the assembly of inflammasome, may be another promising therapeutic strategy. Lonidamine (LND), a small-molecule inhibitor of glycolysis used as an antineoplastic drug, has been evidenced to have anti-inflammation effects. However, its anti-inflammatory mechanism is still largely unknown. METHODS: Middle cerebral artery occlusion (MCAO), experimental autoimmune encephalomyelitis (EAE) and LPS-induced sepsis mice models were constructed to investigate the therapeutic and anti-inflammasome effects of LND. The inhibition of inflammasome activation and ASC oligomerization by LND was evaluated using western blot (WB), immunofluorescence (IF), quantitative polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay (ELISA) in murine bone marrow-derived macrophages (BMDMs). Direct binding of LND with ASC was assessed using molecular mock docking, surface plasmon resonance (SPR), and drug affinity responsive target stability (DARTS). RESULTS: Here, we find that LND strongly attenuates the inflammatory injury in experimental models of inflammasome-associated diseases including autoimmune disease-multiple sclerosis (MS), ischemic stroke and sepsis. Moreover, LND blocks diverse types of inflammasome activation independent of its known targets including hexokinase 2 (HK2). We further reveal that LND directly binds to the inflammasome ligand ASC and inhibits its oligomerization. CONCLUSIONS: Taken together, our results identify LND as a broad-spectrum inflammasome inhibitor by directly targeting ASC, providing a novel candidate drug for the treatment of inflammasome-driven diseases in clinic.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Sepse , Humanos , Camundongos , Animais , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Encefalomielite Autoimune Experimental/tratamento farmacológico
6.
Plant Cell Rep ; 41(7): 1531-1548, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35507055

RESUMO

KEY MESSAGE: Hydrogen sulfide positively regulates autophagy and the expression of hypoxia response-related genes under submergence to enhance the submergence tolerance of Arabidopsis. Flooding seriously endangers agricultural production, and it is quite necessary to explore the mechanism of plant response to submergence for improving crop yield. Both hydrogen sulfide (H2S) and autophagy are involved in the plant response to submergence. However, the mechanisms by which H2S and autophagy interact and influence submergence tolerance have not been thoroughly elucidated. Here, we reported that exogenous H2S pretreatment increased the level of endogenous H2S and alleviated plant cell death under submergence. And transgenic lines decreased in the level of endogenous H2S, L-cysteine desulfurase 1 (des1) mutant and 35S::GFP-O-acetyl-L-serine(thiol)lyase A1 (OASA1)/des1-#56/#61, were sensitive to submergence, along with the lower transcript levels of hypoxia response genes, LOB DOMAIN 41 (LBD41) and HYPOXIA RESPONSIVE UNKNOWN PROTEIN 43 (HUP43). Submergence induced the formation of autophagosomes, and the autophagy-related (ATG) mutants (atg4a/4b, atg5, atg7) displayed sensitive phenotypes to submergence. Simultaneously, H2S pretreatment repressed the autophagosome producing under normal conditions, but enhanced this process under submergence by regulating the expression of ATG genes. Moreover, the mutation of DES1 aggravated the sensitivity of des1/atg5 to submergence by reducing the formation of autophagosomes under submergence. Taken together, our results demonstrated that H2S alleviated cell death through regulating autophagy and the expression of hypoxia response genes during submergence in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Sulfeto de Hidrogênio , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Autofagia , Morte Celular , Cistationina gama-Liase/genética , Cistationina gama-Liase/metabolismo , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , Hipóxia
7.
J Ultrasound Med ; 41(6): 1497-1507, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34549454

RESUMO

OBJECTIVE: To externally validate the Ovarian-adnexal Reporting and Data System (O-RADS) and evaluate its performance in differentiating benign from malignant adnexal masses (AMs) compared with the Gynecologic Imaging Reporting and Data System (GI-RADS) and Assessment of Different NEoplasias in the adneXa (ADNEX). METHODS: A retrospective analysis was performed on 734 cases from the Second Affiliated Hospital of Fujian Medical University. All patients underwent transvaginal or transabdominal ultrasound examination. Pathological diagnoses were obtained for all the included AMs. O-RADS, GI-RADS, and ADNEX were used to evaluate AMs by two sonologists, and the diagnostic efficacy of the three systems was analyzed and compared using pathology as the gold standard. We used the kappa index to evaluate the inter-reviewer agreement (IRA). RESULTS: A total of 734 AMs, including 564 benign masses, 69 borderline masses, and 101 malignant masses were included in this study. O-RADS (0.88) and GI-RADS (0.90) had lower sensitivity than ADNEX (0.95) (P < .05), and the PPV of O-RADS (0.98) was higher than that of ADNEX (0.96) (P < .05). These three systems showed good IRA. CONCLUSION: O-RADS, GI-RADS, and ADNEX showed little difference in diagnostic performance among resident sonologists. These three systems have their own characteristics and can be selected according to the type of center, access to patients' clinical data, or personal comfort.


Assuntos
Doenças dos Anexos , Neoplasias Ovarianas , Doenças dos Anexos/diagnóstico por imagem , Sistemas de Dados , Feminino , Humanos , Neoplasias Ovarianas/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia/métodos
8.
Mikrochim Acta ; 189(3): 107, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35166943

RESUMO

A near-infrared nitrogen and sulfur co-doped carbon dot (N,S-CD)-based ratiometric fluorescent probe is proposed that is synthesized via hydrothermal approach using glutathione and formamide as precursor for sensing and imaging of Zn2+. The prepared N,S-CDs facilitate binding with Zn2+ owing to N and S atom doping. The ratio (I650/I680) of fluorescence intensity at 650 nm and 680 nm increased with the concentrations of Zn2+ when the excitation wavelength was 415 nm. The linearity range was 0.01 to 1.0 µM Zn2+with a detection limit of 5.0 nM Zn2+. The proposed probe was applied to label-free monitoring of Zn2+ in real samples and fluorescent imaging of Zn2+ in living cells, which confirmed its promising applications.


Assuntos
Corantes Fluorescentes/química , Imagem Óptica , Zinco/análise , Carbono/química , Células Hep G2 , Humanos , Nitrogênio/química , Pontos Quânticos/química , Espectrometria de Fluorescência , Enxofre/química
9.
J Pharmacol Exp Ther ; 373(3): 463-475, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32238453

RESUMO

Leonurine (LEO) is a bioactive small molecular compound that has protective effects on the cardiovascular system and prevents the early progression of atherosclerosis; however, it is not clear whether LEO is effective for plaque stability. A novel mouse atherosclerosis model involving tandem stenosis (TS) of the right carotid artery combined with western diet (WD) feeding was used. Apolipoprotein E gene-deficient mice were fed with a WD and received LEO administration daily for 13 weeks. TS was introduced 6 weeks after the onset of experiments. We found that LEO enhanced plaque stability by increasing fibrous cap thickness and collagen content while decreasing the population of CD68-positive cells. Enhanced plaque stability by LEO was associated with the nitric oxide synthase (NOS)-nitric oxide (NO) system. LEO restored the balance between endothelial NOS(E)- and inducible NOS(iNOS)-derived NO production; suppressed the NF-κB signaling pathway; reduced the level of the inflammatory infiltration in plaque, including cytokine interleukin 6; and downregulated the expression of adhesion molecules. These findings support the distinct role of LEO in plaque stabilization. In vitro studies with oxidized low-density lipoprotein-challenged human umbilical vein endothelial cells revealed that LEO balanced NO production and inhibited NF-κB/P65 nuclear translocation, thus mitigating inflammation. In conclusion, the restored balance of the NOS-NO system and mitigated inflammation contribute to the plaque-stabilizing effect of LEO. SIGNIFICANCE STATEMENT: LEO restored the balance between endothelial NOS and inducible NOS in NO production and inhibited excessive inflammation in atherosclerotic "unstable" and rupture-prone plaques in apolipoprotein E gene-deficient mice. The protective effect of LEO for stabilizing atherosclerotic plaques was due to improved collagen content, increased fibrous cap thickness, and decreased accumulation of macrophages/foam cells. So far, LEO has passed the safety and feasibility test of phase I clinical trial.


Assuntos
Aterosclerose/tratamento farmacológico , Ácido Gálico/análogos & derivados , Inflamação/tratamento farmacológico , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico/metabolismo , Placa Aterosclerótica/tratamento farmacológico , Animais , Aterosclerose/metabolismo , Linhagem Celular , Ácido Gálico/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Placa Aterosclerótica/metabolismo , Transdução de Sinais/efeitos dos fármacos
10.
BMC Musculoskelet Disord ; 21(1): 26, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931772

RESUMO

BACKGROUND: It has been reported that miR-93-5p and long non-coding RNA (lncRNA) Cancer Susceptibility 2 (CASC2) play opposite roles in regulating chondrocyte apoptosis, indicating the possible interaction between them. This study aimed to investigate the interaction between miR-93-5p and lncRNA CASC2 in chondrocyte apoptosis, which plays critical roles in osteoarthritis (OA). METHODS: The interaction between CASC2 and miR-93-5p was analyzed by dual luciferase assay and overexpression experiments. Levels of CASC2 and miR-93-5p in plasma sample from OA patients and healthy controls were measured by RT-qPCR. The roles of CASC2 and miR-93-5p in regulating the apoptosis of chondrocyte induced by LPS were analyzed by cell apoptosis assay. RESULTS: Through bioinformatics analysis we observed the potential interaction between CASC2 and miR-93-5p, which was confirmed by dual luciferase assay. In OA patients, miR-93-5p was downregulated, while CASC2 was upregulated, and they were inversely correlated. LPS treatment led to downregulated miR-93-5p and upregulated CASC2. Overexpression of miR-93-5p led to the downregulated CASC2 in chondrocytes. Under LPS treatment, CASC2 overexpression promoted the apoptosis of chondrocyte. MiR-93-5p overexpression played an opposite role and attenuated the effects of CASC2 overexpression. CONCLUSION: MiR-93-5p was downregulated in OA may inhibit LPS-induced chondrocyte apoptosis by targeting lncRNA CASC2.


Assuntos
Apoptose , Condrócitos/fisiologia , MicroRNAs/metabolismo , Osteoartrite/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Líquido Sinovial/metabolismo
11.
J Neurochem ; 144(2): 186-200, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29205357

RESUMO

Hyperglycolysis, observed within the penumbra zone during brain ischemia, was shown to be detrimental for tissue survival because of lactate accumulation and reactive oxygen species overproduction in clinical and experimental settings. Recently, mounting evidence suggests that glycolytic reprogramming and induced metabolic enzymes can fuel the activation of peripheral immune cells. However, the possible roles and details regarding hyperglycolysis in neuroinflammation during ischemia are relatively poorly understood. Here, we investigated whether overactivated glycolysis could activate microglia and identified the crucial regulators of neuroinflammatory responses in vitro and in vivo. Using BV 2 and primary microglial cultures, we found hyperglycolysis and induction of the key glycolytic enzyme hexokinase 2 (HK2) were essential for microglia-mediated neuroinflammation under hypoxia. Mechanistically, HK2 up-regulation led to accumulated acetyl-coenzyme A, which accounted for the subsequent histone acetylation and transcriptional activation of interleukin (IL)-1ß. The inhibition and selective knockdown of HK2 in vivo significantly protected against ischemic brain injury by suppressing microglial activation and IL-1ß production in male Sprague-Dawley rats subjected to transient middle cerebral artery occlusion (MCAo) surgery. We provide novel insights for HK2 specifically serving as a neuroinflammatory determinant, thus explaining the neurotoxic effect of hyperglycolysis and indicating the possibility of selectively targeting HK2 as a therapeutic strategy in acute ischemic stroke.


Assuntos
Isquemia Encefálica/enzimologia , Isquemia Encefálica/genética , Glicólise/genética , Hexoquinase/genética , Hexoquinase/metabolismo , Ativação de Macrófagos/genética , Microglia/enzimologia , Acidente Vascular Cerebral/enzimologia , Acidente Vascular Cerebral/genética , Acetilcoenzima A/metabolismo , Acetilação , Animais , Indução Enzimática/genética , Hexoquinase/biossíntese , Histonas/metabolismo , Infarto da Artéria Cerebral Média/genética , Infarto da Artéria Cerebral Média/metabolismo , Inflamação/genética , Interleucina-1beta/metabolismo , Masculino , Interferência de RNA , Ratos , Ratos Sprague-Dawley
12.
Artigo em Inglês | MEDLINE | ID: mdl-28473204

RESUMO

Hyperdynamic circulation contributes to the progress of portal hypertension in liver cirrhosis. We investigated the effects of soluble epoxide hydrolase (sEH) inhibition on portal pressure and the myogenic response of mesenteric arteries isolated from cirrhotic rats using the sEH inhibitor t-TUCB (trans-4-{4-[3-(4-trifluoromethoxyphenyl)-ureido]cyclohexyloxy}benzoic acid). Cirrhotic tissues had a higher ratio of epoxyeicosatrienoic acids (EETs) to dihydroxyeicosatrienoic acids (DHETs) following increased CYP2C11 expression, which may be a protective response. In comparison with controls, myogenic responses of mesenteric arteries from cirrhotic rats were attenuated at 80-140mmHg, while inhibition of sEH partly reversed the impaired myogenic constriction at 100-140mmHg and exhibited better feedback of vascular smooth muscle to pressure variation. Inhibition of sEH reduced portal pressure by decreasing endothelial synthesis of nitric oxide. An imbalance between EETs and nitric oxide may account for hyperdynamic circulation. sEH inhibitors may provide a novel approach for treating cirrhosis of the liver.


Assuntos
Inibidores Enzimáticos/farmacologia , Epóxido Hidrolases/antagonistas & inibidores , Epóxido Hidrolases/química , Cirrose Hepática/fisiopatologia , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/fisiopatologia , Pressão na Veia Porta/efeitos dos fármacos , Animais , Benzoatos/farmacologia , Ácidos Graxos Monoinsaturados/metabolismo , Cirrose Hepática/metabolismo , Masculino , Óxido Nítrico/metabolismo , Compostos de Fenilureia/farmacologia , Ratos , Ratos Sprague-Dawley , Solubilidade , Vasoconstrição/efeitos dos fármacos
13.
J Biomed Inform ; 73: 115-124, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28712748

RESUMO

In this paper, we develop a novel formulation for contemporaneous patient risk monitoring by exploiting the emerging data-rich environment in many healthcare applications, where an abundance of longitudinal data that reflect the degeneration of the health condition can be continuously collected. Our objective, and the developed formulation, is fundamentally different from many existing risk score models for different healthcare applications, which mostly focus on predicting the likelihood of a certain outcome at a pre-specified time. Rather, our formulation translates multivariate longitudinal measurements into a contemporaneous health index (CHI) that captures patient condition changes over the course of progression. Another significant feature of our formulation is that, CHI can be estimated with or without label information, different from other risk score models strictly based on supervised learning. To develop this formulation, we focus on the degenerative disease conditions, for which we could utilize the monotonic progression characteristic (either towards disease or recovery) to learn CHI. Such a domain knowledge leads us to a novel learning formulation, and on top of that, we further generalize this formulation with a capacity to incorporate label information if available. We further develop algorithms to mitigate the challenges associated with the nonsmooth convex optimization problem by first identifying its dual reformulation as a constrained smooth optimization problem, and then, using the block coordinate descent algorithm to iteratively solve the optimization with a derived efficient projection at each iteration. Extensive numerical studies are performed on both synthetic datasets and real-world applications on Alzheimer's disease and Surgical Site Infection, which demonstrate the utility and efficacy of the proposed method on degenerative conditions that include a wide range of applications.


Assuntos
Algoritmos , Doença de Alzheimer , Humanos , Medição de Risco
14.
Proc Natl Acad Sci U S A ; 111(42): E4504-12, 2014 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-25288727

RESUMO

Oncolytic virotherapy is a growing treatment modality that uses replicating viruses as selective antineoplastic agents. Safety and efficacy considerations dictate that an ideal oncolytic agent would discriminate between normal and cancer cells on the basis of common genetic abnormalities in human cancers. Here, we identify a naturally occurring alphavirus (M1) as a novel selective killer targeting zinc-finger antiviral protein (ZAP)-deficient cancer cells. In vitro, in vivo, and ex vivo studies showed potent oncolytic efficacy and high tumor tropism of M1. We showed that the selectivity depends on ZAP deficiency by systematic identification. A large-scale multicenter pathology study using tissue microarrays reveals that ZAP is commonly deficient in human cancers, suggesting extensive application prospects for M1. Additionally, M1 killed cancer cells by inducing endoplasmic reticulum stress-mediated apoptosis. Our report provides novel insights into potentially personalized cancer therapy using oncolytic viruses.


Assuntos
Alphavirus/classificação , Neoplasias/terapia , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/classificação , Animais , Apoptose , Caspases/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Retículo Endoplasmático/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Transplante de Neoplasias , Neoplasias/metabolismo , Interferência de RNA , Análise Serial de Tecidos , Dedos de Zinco
15.
Blood ; 123(13): 2094-101, 2014 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-24497537

RESUMO

Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by complement-mediated intravascular hemolysis due to the lack of CD55 and CD59 on affected erythrocytes. The anti-C5 antibody eculizumab has proven clinically effective, but uncontrolled C3 activation due to CD55 absence may result in opsonization of erythrocytes, possibly leading to clinically meaningful extravascular hemolysis. We investigated the effect of the peptidic C3 inhibitor, compstatin Cp40, and its long-acting form (polyethylene glycol [PEG]-Cp40) on hemolysis and opsonization of PNH erythrocytes in an established in vitro system. Both compounds demonstrated dose-dependent inhibition of hemolysis with IC50 ∼4 µM and full inhibition at 6 µM. Protective levels of either Cp40 or PEG-Cp40 also efficiently prevented deposition of C3 fragments on PNH erythrocytes. We further explored the potential of both inhibitors for systemic administration and performed pharmacokinetic evaluation in nonhuman primates. A single intravenous injection of PEG-Cp40 resulted in a prolonged elimination half-life of >5 days but may potentially affect the plasma levels of C3. Despite faster elimination kinetics, saturating inhibitor concentration could be reached with unmodified Cp40 through repetitive subcutaneous administration. In conclusion, peptide inhibitors of C3 activation effectively prevent hemolysis and C3 opsonization of PNH erythrocytes, and are excellent, and potentially cost-effective, candidates for further clinical investigation.


Assuntos
Ativação do Complemento/efeitos dos fármacos , Complemento C3/antagonistas & inibidores , Hemoglobinúria Paroxística/tratamento farmacológico , Peptídeos Cíclicos/uso terapêutico , Animais , Desenho de Fármacos , Eritrócitos/efeitos dos fármacos , Eritrócitos/fisiologia , Meia-Vida , Hemoglobinúria Paroxística/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Macaca fascicularis , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/uso terapêutico , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Polietilenoglicóis/farmacologia , Polietilenoglicóis/uso terapêutico
16.
Analyst ; 141(14): 4488-94, 2016 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-27197565

RESUMO

A novel dual-emitting fluorescence probe is developed for rapid and ultrasensitive detection of Fe(3+). The nanoprobe is prepared by coating CdSe semiconductor quantum dots (SQDs) onto the surface of carbon nanodot (CND) doped TiO2 microspheres. The as-prepared nanoprobe exhibits the corresponding dual emissions at 436 and 596 nm for CNDs and CdSe, respectively, under a single excitation wavelength. The blue fluorescence of the CNDs is insensitive to Fe(3+), whereas the orange emission of the CdSe SQDs is functionalized to be selectively quenched by Fe(3+). The intensity ratio of I436/I596 shows a good linear relationship with the concentration of Fe(3+) in the range of 10(-9) to 10(-5) M. The nanoprobe provides an effective platform for the reliable detection of Fe(3+) with a detection limit as low as 10 nM. Besides, this ratiometric nanosensor exhibits good selectivity for Fe(3+) over other metal ions. The results reveal that the nanoprobe could provide a sensitive sensor for rapid detection of Fe(3+) with high selectivity and sensitivity. Moreover, 293T cells are used as models to achieve a potential application as a probe for monitoring Fe(3+) in cells. Thus, these dual-emitting nanoprobes could work as an alternative to conventional fluorescence probes for biolabeling, sensing and other applications.


Assuntos
Carbono , Ferro/análise , Nanopartículas Metálicas , Pontos Quânticos , Corantes Fluorescentes , Células HEK293 , Humanos , Limite de Detecção , Espectrometria de Fluorescência , Titânio
17.
J Neurosci ; 34(34): 11426-38, 2014 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-25143622

RESUMO

Overstimulation of NMDA-type glutamate receptors is believed to be responsible for neuronal death of the CNS in various disorders, including cerebral and spinal cord ischemia. However, the intrinsic and physiological mechanisms of modulation of these receptors are essentially unknown. Here we report that cholestane-3ß,5α,6ß-triol (triol), a major metabolite of cholesterol, is an endogenous neuroprotectant and protects against neuronal injury both in vitro and in vivo via negative modulation of NMDA receptors. Treatment of cultured neurons with triol protects against glutamate-induced neurotoxicity, and administration of triol significantly decreases neuronal injury after spinal cord ischemia in rabbits and transient focal cerebral ischemia in rats. An inducible elevation of triol is associated with ischemic preconditioning and subsequent neuroprotection in the spinal cord of rabbits. This neuroprotection is effectively abolished by preadministration of a specific inhibitor of triol synthesis. Physiological concentrations of triol attenuate [Ca(2+)]i induced by glutamate and decrease inward NMDA-mediated currents in cultured cortical neurons and HEK-293 cells transiently transfected with NR1/NR2B NMDA receptors. Saturable binding of [(3)H]triol to cerebellar granule neurons and displacement of [(3)H]MK-801 binding to NMDA receptors by triol suggest that direct blockade of NMDA receptors may underlie the neuroprotective properties. Our findings suggest that the naturally occurring oxysterol, the major cholesterol metabolite triol, functions as an endogenous neuroprotectant in vivo, which may provide novel insights into understanding and developing potential therapeutics for disorders in the CNS.


Assuntos
Lesões Encefálicas/prevenção & controle , Colestanóis/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Isquemia do Cordão Espinal/prevenção & controle , Adulto , Animais , Lesões Encefálicas/etiologia , Células Cultivadas , Sistema Nervoso Central/citologia , Colestanóis/sangue , Modelos Animais de Doenças , Maleato de Dizocilpina/farmacocinética , Antagonistas de Aminoácidos Excitatórios/farmacocinética , Feminino , Ácido Glutâmico/farmacologia , Humanos , Infarto da Artéria Cerebral Média/complicações , Masculino , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ligação Proteica/efeitos dos fármacos , Coelhos , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia , Adulto Jovem
18.
Ophthalmology ; 122(4): 787-95, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25556116

RESUMO

PURPOSE: To describe the prevalence and interrelationships of epiretinal membranes (ERMs), vitreomacular traction (VMT), macular cysts, paravascular cysts (PVCs), lamellar macular holes (LMHs), full-thickness macular holes (FTMHs), and visual impairment in a population-based study of older adults. DESIGN: Cross-sectional study. PARTICIPANTS: There were 1913 participants aged 63 to 102 years at the 20-year Beaver Dam Eye Study follow-up examination in 2008-2010, of whom 1540 (2980 eyes) had gradable spectral-domain optical coherence tomography (SD OCT) scans of the macula in at least 1 eye. METHODS: The presence of ERMs and other retinal lesions was determined by standardized grading of macular SD OCT scans and photographs of 3 standard fields. MAIN OUTCOME MEASURES: Epiretinal membranes, VMT, macular cysts, PVCs, LMHs, FTMHs, and visual impairment. RESULTS: By using SD OCT, the prevalence of ERMs (34.1%), VMT (1.6%), macular cysts (5.6%), PVCs (20.0%), LMHs (3.6%), and FTMHs (0.4%) was estimated. The prevalence of macular cysts (P < 0.001), ERMs (P < 0.001), and VMT (P = 0.005) increased with age; the prevalence of PVCs (P = 0.05) decreased with age; and the prevalence of LMHs was not associated with age (P = 0.70). The prevalence of macular cysts, LMHs, and ERMs was higher in eyes with a history of cataract surgery. Macular cysts and ERMs were more common in eyes with retinal diseases, such as proliferative diabetic retinopathy, retinal vein occlusion, and retinal detachment, than in eyes without these conditions. Macular cysts, ERMs, and FTMHs were associated with visual impairment. While adjusting for age and sex, macular cysts (odds ratio [OR], 3.96; P < 0.0001), PVCs (OR, 1.45, P = 0.007), LMHs (OR, 10.62; P < 0.001), VMT (OR, 2.72, P = 0.01), and visual impairment (OR, 3.23; P < 0.001) were more frequent in eyes with ERMs compared with eyes without ERMs. CONCLUSIONS: Epiretinal membranes are associated with macular cysts, PVCs, LMHs, VMT, and visual impairment. Further follow-up will allow better understanding of the natural history of ERMs and VMT and their relationships to the development of macular cysts and LMHs in the aging population.


Assuntos
Membrana Epirretiniana/epidemiologia , Edema Macular/epidemiologia , Doenças Retinianas/epidemiologia , Perfurações Retinianas/epidemiologia , Descolamento do Vítreo/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Membrana Epirretiniana/diagnóstico , Feminino , Humanos , Edema Macular/diagnóstico , Masculino , Pessoa de Meia-Idade , Fotografação , Prevalência , Doenças Retinianas/diagnóstico , Perfurações Retinianas/diagnóstico , Aderências Teciduais , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia , Pessoas com Deficiência Visual/estatística & dados numéricos , Descolamento do Vítreo/diagnóstico , Wisconsin/epidemiologia
19.
Analyst ; 140(16): 5634-9, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26133700

RESUMO

A one-pot sonochemical reaction of Cu(NO3)2 with glutathione (GSH), the latter functioning as a reducing agent and a stabilizing agent, rapidly affords Cu nanoclusters (NCs). The as-prepared GSH-CuNCs possess a small size (∼2.2 ± 0.2 nm), red luminescence with quantum yield (5.3%), and water-dispersibility. Moreover, the fluorescence of the as-prepared GSH-CuNCs is responsive to pH so that the intensity of fluorescence increases rapidly with decreasing pH from 9 to 4. Besides, the GSH-CuNCs would be aggregated by Pb(2+) ions in aqueous solution which results in quenching of the fluorescence. Therefore, such GSH-CuNCs would be excellent candidates as fluorescent probes for the label-free detection of Pb(2+) with the limit of detection at 1.0 nM. Importantly, CAL-27 cells are used as models to achieve potential application as probes for monitoring Pb(2+) in living cells. Thus, these fluorescent CuNCs could work as an alternative to conventional fluorescent probes for biolabeling, sensing and other applications.


Assuntos
Bioensaio/métodos , Cobre/química , Chumbo/análise , Nanopartículas Metálicas/química , Linhagem Celular Tumoral , Glutationa/química , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Microscopia Eletrônica de Transmissão , Sonicação
20.
SAGE Open Med ; 12: 20503121241257190, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38826826

RESUMO

Objective: We explored the differences in deep venous catheterization-associated complications between patients with hematological malignancies after peripherally inserted central catheter placement and such patients after implantable venous access port catheterization. Introduction: peripherally inserted central catheters and implantable venous access ports are the most popular devices used for chemotherapy. However, no study has revealed differences between peripherally inserted central catheters and implantable venous access ports in Chinese patients with hematological malignancies. Methods: The clinical data of 322 patients with hematological malignancies who were treated from January 1, 2020 to December 30, 2021 were included in a retrospective cohort study. Postoperative color Doppler ultrasonography and follow-up results were used to compare the incidence rates of deep venous catheterization -associated complications after peripherally inserted central catheters and implantable venous access ports catheterization. Results: The relative risk of catheter-related complications considering the type of device was 8.3 (95% CI = 3.0-22.8). In addition, chi-square segmentation analysis revealed a significant difference in the complication rate between the internal jugular vein and the basilic vein (χ2 = 22.002, p < 0.0001) and between the subclavian vein and the basilic vein (χ2 = 28.940, p < 0.0001). Conclusion: Implantable venous access ports are safer than peripherally inserted central catheters for Chinese patients with hematological malignancies. The implantation of implantable venous access ports could be firstly considered for systematic anti-cancer treatment.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA