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1.
Nature ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862027

RESUMO

The recent acceleration of commercial, private, and multi-national spaceflight has created an unprecedented level of activity in low Earth orbit (LEO), concomitant with the highest-ever number of crewed missions entering space and preparations for exploration-class (>1 year) missions. Such rapid advancement into space from many new companies, countries, and space-related entities has enabled a"Second Space Age." This new era is also poised to leverage, for the first time, modern tools and methods of molecular biology and precision medicine, thus enabling precision aerospace medicine for the crews. The applications of these biomedical technologies and algorithms are diverse, encompassing multi-omic, single-cell, and spatial biology tools to investigate human and microbial responses to spaceflight. Additionally, they extend to the development of new imaging techniques, real-time cognitive assessments, physiological monitoring, and personalized risk profiles tailored for astronauts. Furthermore, these technologies enable advancements in pharmacogenomics (PGx), as well as the identification of novel spaceflight biomarkers and the development of corresponding countermeasures. In this review, we highlight some of the recent biomedical research from the National Aeronautics and Space Administration (NASA), Japan Aerospace Exploration Agency (JAXA), European Space Agency (ESA), and other space agencies, and also detail the commercial spaceflight sector's (e.g. SpaceX, Blue Origin, Axiom, Sierra Space) entrance into aerospace medicine and space biology, the first aerospace medicine biobank, and the myriad upcoming missions that will utilize these tools to ensure a permanent human presence beyond LEO, venturing out to other planets and moons.

2.
J Neurosci ; 44(14)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38360746

RESUMO

An increasing number of pathogenic variants in presynaptic proteins involved in the synaptic vesicle cycle are being discovered in neurodevelopmental disorders. The clinical features of these synaptic vesicle cycle disorders are diverse, but the most prevalent phenotypes include intellectual disability, epilepsy, movement disorders, cerebral visual impairment, and psychiatric symptoms ( Verhage and Sørensen, 2020; Bonnycastle et al., 2021; John et al., 2021; Melland et al., 2021). Among this growing list of synaptic vesicle cycle disorders, the most frequent is STXBP1 encephalopathy caused by de novo heterozygous pathogenic variants in syntaxin-binding protein 1 (STXBP1, also known as MUNC18-1; Verhage and Sørensen, 2020; John et al., 2021). STXBP1 is an essential protein for presynaptic neurotransmitter release. Its haploinsufficiency is the main disease mechanism and impairs both excitatory and inhibitory neurotransmitter release. However, the disease pathogenesis and cellular origins of the broad spectrum of neurological phenotypes are poorly understood. Here we generate cell type-specific Stxbp1 haploinsufficient male and female mice and show that Stxbp1 haploinsufficiency in GABAergic/glycinergic neurons causes developmental delay, epilepsy, and motor, cognitive, and psychiatric deficits, recapitulating majority of the phenotypes observed in the constitutive Stxbp1 haploinsufficient mice and STXBP1 encephalopathy. In contrast, Stxbp1 haploinsufficiency in glutamatergic neurons results in a small subset of cognitive and seizure phenotypes distinct from those caused by Stxbp1 haploinsufficiency in GABAergic/glycinergic neurons. Thus, the contrasting roles of excitatory and inhibitory signaling reveal GABAergic/glycinergic dysfunction as a key disease mechanism of STXBP1 encephalopathy and suggest the possibility to selectively modulate disease phenotypes by targeting specific neurotransmitter systems.


Assuntos
Encefalopatias , Epilepsia , Transtornos do Neurodesenvolvimento , Animais , Feminino , Masculino , Camundongos , Encefalopatias/genética , Epilepsia/genética , Neurônios GABAérgicos/metabolismo , Proteínas Munc18/genética , Proteínas Munc18/metabolismo , Transtornos do Neurodesenvolvimento/genética , Neurotransmissores
3.
Eur Radiol ; 34(3): 1411-1421, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37646808

RESUMO

OBJECTIVES: This study evaluated the collateral map's ability to predict lesion growth and penumbra after acute anterior circulation ischemic strokes. METHODS: This was a retrospective analysis of selected data from a prospectively collected database. The lesion growth ratio was the ratio of the follow-up lesion volume to the baseline lesion volume on diffusion-weighted imaging (DWI). The time-to-maximum (Tmax)/DWI ratio was the ratio of the baseline Tmax > 6 s volume to the baseline lesion volume. The collateral ratio was the ratio of the hypoperfused lesion volume of the phase_FU (phase with the hypoperfused lesions most approximate to the follow-up DWI lesion) to the hypoperfused lesion volume of the phase_baseline of the collateral map. Multiple logistic regression analyses were conducted to identify independent predictors of lesion growth. The concordance correlation coefficients of Tmax/DWI ratio and collateral ratio for lesion growth ratio were analyzed. RESULTS: Fifty-two patients, including twenty-six males (mean age, 74 years), were included. Intermediate (OR, 1234.5; p < 0.001) and poor collateral perfusion grades (OR, 664.7; p = 0.006) were independently associated with lesion growth. Phase_FUs were immediately preceded phases of the phase_baselines in intermediate or poor collateral perfusion grades. The concordance correlation coefficients of the Tmax/DWI ratio and collateral ratio for the lesion growth ratio were 0.28 (95% CI, 0.17-0.38) and 0.88 (95% CI, 0.82-0.92), respectively. CONCLUSION: Precise prediction of lesion growth and penumbra can be possible using collateral maps, allowing for personalized application of recanalization treatments. Further studies are needed to generalize the findings of this study. CLINICAL RELEVANCE STATEMENT: Precise prediction of lesion growth and penumbra can be possible using collateral maps, allowing for personalized application of recanalization treatments. KEY POINTS: • Cell viability in cerebral ischemia due to proximal arterial steno-occlusion mainly depends on the collateral circulation. • The collateral map shows salvageable brain extent, which can survive by recanalization treatments after acute anterior circulation ischemic stroke. • Precise estimation of salvageable brain makes it possible to make patient-specific treatment decision.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Humanos , Idoso , AVC Isquêmico/complicações , AVC Isquêmico/patologia , Estudos Retrospectivos , Isquemia Encefálica/complicações , Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Circulação Colateral , Circulação Cerebrovascular
4.
Inorg Chem ; 62(24): 9563-9577, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37270704

RESUMO

Compounds with ordered and interconnected channels have versatile multifunctional applications in technological fields. In this work, we report the intrinsic- and Eu3+-activated luminescence in NbAlO4 with a wide channel structure. NbAlO4 is an n-type semiconductor with an indirect allowed transition and a band-gap energy of 3.26 eV. The conduction band and valence band are composed of Nb 3d and O 2p states, respectively. Unlike the common niobate oxide Nb2O5, NbAlO4 exhibits efficient self-activated luminescence with good thermal stability even at room temperature. The AlO4 tetrahedron effectively blocks the transfer/dispersion of excitation energy between NbO6 chains in NbAlO4, allowing for effective self-activated luminescence from NbO6 activation centers. Moreover, Eu3+-doped NbAlO4 displayed a bright red luminescence of 5D0 → 7F2 transition at 610 nm. The site-selective excitation and luminescence of Eu3+ ions in a spectroscopic probe were utilized to investigate the doping mechanism. It is evidenced that Eu3+ is doped in the structure channel in NbAlO4 lattices, not in the normal cation sites of Nb5+ or Al3+. The experimental findings are valuable in developing new luminescent materials and improving the understanding of the material's channel structure.

5.
Int J Mol Sci ; 25(1)2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38203694

RESUMO

We synthesized novel polyelectrolytes based on naphthalene diimide with quaternary amine featuring hydroxyl groups at the side chain, along with different counteranions (PF-NDIN-Br-OH and PF-NDIN-I-OH) for polymer solar cell (PSC) application as the interlayer. The polyelectrolytes establish a beneficial interface dipole through the ionic moieties and synergistic effects arising from the hydroxyl groups located at the side chain. Incorporating polyelectrolytes as the cathode interlayer resulted in an enhancement of the power conversion efficiency (PCE). The PCE of the device with PF-NDIN-Br-OH increased from 8.96% to 9.51% compared to the ZnO-only device. The best PCE was obtained with the device based on PF-NDIN-I-OH, up to 9.59% resulting from the Jsc enhancement. This outcome implies a correlation between the performance of the device and the synergistic effects observed in polyelectrolytes containing hydroxyl groups in the side chain, along with larger anions when employed in PSCs.


Assuntos
Imidas , Naftalenos , Polímeros , Polieletrólitos , Eletrodos
6.
Int J Mol Sci ; 24(13)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37446313

RESUMO

Mechanical unloading during microgravity causes skeletal muscle atrophy and impairs mitochondrial energetics. The elevated production of reactive oxygen species (ROS) by mitochondria and Nox2, coupled with impairment of stress protection (e.g., SIRT1, antioxidant enzymes), contribute to atrophy. We tested the hypothesis that the SIRT1 activator, SRT2104 would rescue unloading-induced mitochondrial dysfunction. Mitochondrial function in rat gastrocnemius and soleus muscles were evaluated under three conditions (10 days): ambulatory control (CON), hindlimb unloaded (HU), and hindlimb-unloaded-treated with SRT2104 (SIRT). Oxidative phosphorylation, electron transfer capacities, H2O2 production, and oxidative and antioxidant enzymes were quantified using high-resolution respirometry and colorimetry. In the gastrocnemius, (1) integrative (per mg tissue) proton LEAK was lesser in SIRT than in HU or CON; (2) intrinsic (relative to citrate synthase) maximal noncoupled electron transfer capacity (ECI+II) was lesser, while complex I-supported oxidative phosphorylation to ECI+II was greater in HU than CON; (3) the contribution of LEAK to ECI+II was greatest, but cytochrome c oxidase activity was lowest in HU. In both muscles, H2O2 production and concentration was greatest in SIRT, as was gastrocnemius superoxide dismutase activity. In the soleus, H2O2 concentration was greater in HU compared to CON. These results indicate that SRT2104 preserves mitochondrial function in unloaded skeletal muscle, suggesting its potential to support healthy muscle cells in microgravity by promoting necessary energy production in mitochondria.


Assuntos
Antioxidantes , Sirtuína 1 , Ratos , Animais , Antioxidantes/farmacologia , Sirtuína 1/metabolismo , Peróxido de Hidrogênio/metabolismo , Estresse Oxidativo , Músculo Esquelético/metabolismo , Oxirredução , Atrofia Muscular/metabolismo , Mitocôndrias/metabolismo , Membro Posterior/metabolismo , Biologia
7.
Int J Mol Sci ; 24(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36613965

RESUMO

A series of medium bandgap polymer donors, named poly(1-(5-(4,8-bis(5-(2-ethylhexyl)-4-fluorothiophen-2-yl)benzo [1,2-b:4,5-b']dithiophen-2-yl)thiophen-2-yl)-5-((4,5-dihexylthiophen-2-yl)methylene)-3-(thiophen-2-yl)-4H-cyclopenta[c]thiophene-4,6(5H)-dione) (IND-T-BDTF), poly(1-(5-(4,8-bis(5-(2-ethylhexyl)-4-fluorothiophen-2-yl)benzo [1,2-b:4,5-b']dithiophen-2-yl)-4-hexylthiophen-2-yl)-5-((4,5-dihexylthiophen-2-yl)methylene)-3-(4-hexylthiophen-2-yl)-4H-cyclopenta[c]thiophene-4,6(5H)-dione (IND-HT-BDTF), and poly(1-(5-(4,8-bis(5-(2-ethylhexyl)-4-fluorothiophen-2-yl)benzo [1,2-b:4,5-b']dithiophen-2-yl)-6-octylthieno [3,2-b]thiophen-2-yl)-5-((4,5-dihexylthiophen-2-yl)methylene)-3-(6-octylthieno [3,2-b]thiophen-2-yl)-4H-cyclopenta[c]thiophene-4,6(5H)-dione (IND-OTT-BDTF), are developed for non-fullerene acceptors (NFAs) polymer solar cells (PSCs). Three polymers consist of donor-acceptor building block, where the electron-donating fluorinated benzodithiophene (BDTF) unit is linked to the electron-accepting 4H-cyclopenta[c]thiophene-4,6(5H)-dione (IND) derivative via thiophene (T) or thieno [3,2-b]thiopene (TT) bridges. The absorption range of the polymer donors based on IND in this study shows 400~800 nm, which complimenting the absorption of Y6BO (600~1000 nm). The PSC's performances are also significantly impacted by the π-bridges. NFAs inverted type PSCs based on polymer donors and Y6BO acceptor are fabricated. The power conversion efficiency (PCE) of the device based on IND-OTT-BDTF reaches up to 11.69% among all polymers with a short circuit current of 26.37 mA/cm2, an open circuit voltage of 0.79 V, and a fill factor of 56.2%, respectively. This study provides fundamental information on the invention of new polymer donors for NFA-based PSCs.


Assuntos
Fulerenos , Energia Solar , Polímeros/química , Fulerenos/química , Fontes de Energia Elétrica , Tiofenos/química
8.
Anal Chem ; 93(37): 12594-12601, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34491717

RESUMO

Organic carbonate electrolytes are widely used materials for lithium-ion batteries. However, detailed solvation structures and solvent coordination numbers (CNs) of lithium cations in such solutions have not been accurately described nor determined yet. Because transmission-type IR spectroscopy is not of use for measuring the carbonyl stretch modes of electrolytes due to their absorption saturation problem, we here show that simple spacer-free thin cell IR spectroscopy can provide quantitative information on the number of solvating carbonate molecules around each lithium ion. We could estimate the solvent (carbonate) CNs of lithium ions in dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, propylene carbonate, and butylene carbonate over a wide range of lithium salt concentrations accurately, and they are compared with the previous results obtained with attenuated total reflection IR spectroscopy technique. We anticipate that our spacer-free thin cell approach will potentially be used to investigate the solvation dynamics, chemical exchange process, and vibrational energy transfers between solvating carbonate molecules in lithium salt electrolytes when combined with time-resolved IR spectroscopy.


Assuntos
Eletrólitos , Lítio , Carbonatos , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Soft Matter ; 17(13): 3700-3708, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33683277

RESUMO

A concentration gradient in an aqueous solution is a promising source of energy that can be converted into electrical energy by an ion-exchange polymer membrane. In concentration-gradient energy harvesters, ion transport through nanoporous channels is an emerging approach to enhance the energy conversion efficiency. Since massive but selective ion transport could be realized through nanochannels, the theoretical calculations predicted that nanoporous membranes can extract significantly larger energy than the conventional non-structured membranes. In this regard, scientists in the field have attempted to produce nanoporous membranes on a macroscopic scale based on 1D, 2D, and 3D materials. However, the fabrication of nanoporous membranes is often accompanied by technical difficulties, which entails high production cost, low throughput, and poor scalability. In this study, we took advantage of the self-segregating properties of block copolymers (BCPs) to address these issues. In particular, the non-solvent-induced phase separation method has been utilized to produce three-dimensionally interconnected nanopores within BCP membranes. In addition, the neutral BCP nanopores' surface was modified with positive charges to allow selective diffusion of anions in concentration-gradient cells. By mounting the porous BCP membranes between two aqueous solutions with different concentrations, we studied the BCP-membrane-mediated energy-harvesting performance.

10.
Neuroradiology ; 63(9): 1471-1479, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33533948

RESUMO

PURPOSE: To evaluate the role of collateral and permeability imaging derived from dynamic contrast material-enhanced magnetic resonance angiography to predict PH 2 hemorrhagic transformation in acute ischemic stroke. METHODS: The secondary analysis of a published data from participants with acute ischemic stroke. The multiphase collateral map and permeability imaging were generated by using dynamic signals from dynamic contrast material-enhanced magnetic resonance angiography obtained at admission. To identify independent predictors of PH 2 hemorrhagic transformation, age, sex, risk factors, baseline National Institutes of Health Stoke Scale (NIHSS) score, baseline DWI lesion volume, collateral-perfusion status, mode of treatment, and successful early reperfusion were evaluated with multiple logistic regression analyses and the significance of permeability imaging in prediction of PH 2 hemorrhagic transformation was evaluated by subgroup analysis. RESULTS: In 115 participants, including 70 males (mean (SD) age, 69 (12) years), PH 2 hemorrhagic transformation occurred in 6 participants with very poor collateral-perfusion status (MAC 0). MAC 0 (OR, 0.06; 95% CI, 0.01, 0.74; P = .03) was independently associated with PH 2 hemorrhagic transformation. In 22 participants with MAC 0, the permeable signal on Kep permeability imaging was the only significant characteristic associated with PH 2 hemorrhagic transformation (P = .009). The specificity of Kep permeability imaging was 93.8% (95% confidence interval: 69.8, 99.8) in predicting PH 2 hemorrhagic transformation. CONCLUSION: Individual-based prediction of PH 2 hemorrhagic transformation in patients with acute ischemic stroke may be possible with multiphase collateral map and permeability imaging derived from dynamic contrast material-enhanced magnetic resonance angiography.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Idoso , Isquemia Encefálica/diagnóstico por imagem , Meios de Contraste , Humanos , Angiografia por Ressonância Magnética , Masculino , Permeabilidade , Projetos Piloto , Acidente Vascular Cerebral/diagnóstico por imagem
11.
Pers Individ Dif ; 183: 111127, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36569789

RESUMO

The pathogen stress hypothesis posits that pathogen-related threats influence regional and individual differences in collectivism since behavioral practices associated with collectivism limit the spread of infectious diseases. In support of the hypothesis, previous research demonstrates the association between individualism/collectivism and pathogen stress based on historical records or experimental manipulation. However, it is still unclear whether individuals would indeed value collectivism during the outbreak of infectious diseases. Thus, we investigated the concurrent effects of pathogen-related stress on the endorsement of individualism/collectivism by examining 9322 Koreans for 14 weeks of the COVID-19 pandemic. The results revealed that the level of collectivism among respondents were higher after than before the COVID-19 outbreak. Moreover, the average level of collectivism on a given day showed a significant association with the number of confirmed COVID-19 cases on the same day during the outbreak. Interestingly, individualism did not significantly change for the same period.

12.
Molecules ; 26(4)2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33672046

RESUMO

Substituted N-phenyl cinnamamide derivatives were designed and synthesized to confirm activation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathway by the electronic effect on beta-position of Michael acceptor according to introducing the R1 and R2 group. Compounds were screened using the Nrf2/antioxidant response element (ARE)-driven luciferase reporter assay. Compound 1g showed desirable luciferase activity in HepG2 cells without cell toxicity. mRNA and protein expression of Nrf2/ARE target genes such as NAD(P)H quinone oxidoreductase 1, hemeoxygenase-1, and glutamate-cysteine ligase catalytic subunit (GCLC) were upregulated by compound 1g in a concentration-dependent manner. Treatment with 1g resulted in increased endogenous antioxidant glutathione, showing strong correlation with enhanced GCLC expression for synthesis of glutathione. In addition, tert-butyl hydroperoxide (t-BHP)-generated reactive oxygen species were significantly removed by 1g, and the results of a cell survival assay in a t-BHP-induced oxidative cell injury model showed a cytoprotective effect of 1g in a concentration dependent manner. In conclusion, the novel compound 1g can be utilized as an Nrf2/ARE activator in antioxidative therapy.


Assuntos
Cinamatos/farmacologia , Citoproteção/efeitos dos fármacos , Glutationa/biossíntese , Hepatócitos/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Elementos de Resposta Antioxidante/genética , Ácidos Carboxílicos/química , Ácidos Carboxílicos/farmacologia , Morte Celular/efeitos dos fármacos , Cinamatos/química , Glutationa/metabolismo , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Humanos , Luciferases/metabolismo , Fator 2 Relacionado a NF-E2/agonistas , Substâncias Protetoras/farmacologia , terc-Butil Hidroperóxido
13.
Small ; 16(48): e2003865, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33150725

RESUMO

Solution-processed Cu(In,Ga)(S,Se)2  (CIGS) has a great potential for the production of large-area photovoltaic devices at low cost. However, CIGS solar cells processed from solution exhibit relatively lower performance compared to vacuum-processed devices because of a lack of proper composition distribution, which is mainly instigated by the limited Se uptake during chalcogenization. In this work, a unique potassium treatment method is utilized to improve the selenium uptake judiciously, enhancing grain sizes and forming a wider bandgap minimum region. Careful engineering of the bandgap grading structure also results in an enlarged space charge region, which is favorable for electron-hole separation and efficient charge carrier collection. Besides, this device processing approach has led to a linearly increasing electron diffusion length and carrier lifetime with increasing the grain size of the CIGS film, which is a critical achievement for enhancing photocurrent yield. Overall, 15% of power conversion efficiency is achieved in solar cells processed from environmentally benign solutions. This approach offers critical insights for precise device design and processing rules for solution-processed CIGS solar cells.

14.
Pharmacol Res ; 161: 105146, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32814173

RESUMO

Neovascular age-related macular degeneration (nAMD) is a common cause of irreversible vision loss in the elderly. Anti-vascular endothelial growth factor has been effective in treating pathological ocular neovascularization, but it has limitations including the need for repeated intraocular injections for the maintenance of therapeutic effects in most patients and poor or non-response to this agent in some patients. in vitro cellular studies were conducted using retinal pigment epithelial cell lines (ARPE-19 and hTERT-RPE1), human umbilical vein endothelial cells (HUVECs), and human umbilical vein smooth muscle cells (HUVSMCs). in vivo efficacy of ilimaquinone (IQ) was tested in laser-induced choroidal neovascularization mouse and rabbit models. Tissue distribution study was performed in male C57BL6/J mice. IQ, 4,9-friedodrimane-type sesquiterpenoid isolated from the marine sponge, repressed the expression of angiogenic/inflammatory factors and restored the expression of E-cadherin in retinal pigment epithelial cells by inhibiting the Wnt/ß-catenin pathway. In addition, it selectively inhibited proliferation and tube formation of HUVECs by activating the p53 pathway. Topical and intraperitoneal administration of IQ significantly reduced choroidal neovascularization in rabbits and mice with laser-induced choroidal neovascularization. Notably, IQ by the oral route of exposure was highly permeable to the eyes and suppressed abnormal vascular leakage by downregulation of ß-catenin and stabilization of p53 in vivo. Our findings demonstrate that IQ functions through regulation of p53 and Wnt/ß-catenin pathways with conceivable advantages over existing cytokine-targeted anti-angiogenic therapies.


Assuntos
Inibidores da Angiogênese/farmacologia , Neovascularização de Coroide/prevenção & controle , Degeneração Macular/prevenção & controle , Quinonas/farmacologia , Neovascularização Retiniana/prevenção & controle , Vasos Retinianos/efeitos dos fármacos , Sesquiterpenos/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismo , Animais , Linhagem Celular , Neovascularização de Coroide/metabolismo , Neovascularização de Coroide/patologia , Modelos Animais de Doenças , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Degeneração Macular/metabolismo , Degeneração Macular/patologia , Masculino , Camundongos Endogâmicos C57BL , Coelhos , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia , Vasos Retinianos/metabolismo , Vasos Retinianos/patologia
15.
Nat Mater ; 17(3): 253-260, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29403053

RESUMO

Although it is known that molecular interactions govern morphology formation and purity of mixed domains of conjugated polymer donors and small-molecule acceptors, and thus largely control the achievable performance of organic solar cells, quantifying interaction-function relations has remained elusive. Here, we first determine the temperature-dependent effective amorphous-amorphous interaction parameter, χaa(T), by mapping out the phase diagram of a model amorphous polymer:fullerene material system. We then establish a quantitative 'constant-kink-saturation' relation between χaa and the fill factor in organic solar cells that is verified in detail in a model system and delineated across numerous high- and low-performing materials systems, including fullerene and non-fullerene acceptors. Our experimental and computational data reveal that a high fill factor is obtained only when χaa is large enough to lead to strong phase separation. Our work outlines a basis for using various miscibility tests and future simulation methods that will significantly reduce or eliminate trial-and-error approaches to material synthesis and device fabrication of functional semiconducting blends and organic blends in general.

16.
BMC Cancer ; 19(1): 936, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601188

RESUMO

BACKGROUND: The phosphoinositol 3-kinase (PI3K) pathway is associated with poor prognosis of hematologic malignancies, providing a strong rationale for the use of PI3K inhibitors in the treatment of malignant lymphoma. However, development of resistance limits the use of PI3K inhibitors in lymphoma patients. METHODS: We established copanlisib (pan-PI3K inhibitor)-resistant B-cell lymphoma and duvelisib (PI3Kδ and -γ inhibitor)-resistant T-cell lymphoma cell lines. The cytokine array and the phospho-kinase array were used to identify up-regulated proteins in the resistant cells. Cytokine expression and phospho-kinase levels were examined by ELISA and Western blot analysis, respectively. Cell proliferation capabilities were measured by using CCK-8 kit and colony formation assay. The effects of inhibitors on apoptosis were detected using an Annexin V-FITC Apoptosis Detection Kit and a flow cytometry system. The underlying mechanisms were studied by transfecting recombinant plasmids or siRNA into lymphoma cell lines. Cells were transiently transfected using the Amaxa electroporation system. We evaluated the effects of PI3K inhibitor alone and in combination with JAK inhibitor (BSK805) on lymphoma proliferation and signaling pathway activation. RESULTS: Cytokine arrays revealed upregulation of interleukin (IL)-6 in both copanlisib- and duvelisib-resistant cell lines. Phosphorylated STAT5, AKT, p70S6K and MAPK were increased in copanlisib-resistant B-cell lymphoma cells, whereas phosphorylated STAT3 and NF-κB were increased in duvelisib-resistant T cell lymphoma cells. Conversely, depletion of IL-6 sensitized both resistant cell lines, and led to downregulation of phosphorylated STAT3 and STAT5 in copanlisib- and duvelisib-resistant cells, respectively. Moreover, combined treatment with a JAK inhibitor (BSK805) and a PI3K inhibitor circumvented the acquired resistance to PI3K inhibitors in lymphoma, and concurrent inhibition of the activated pathways produced combined effects. CONCLUSIONS: IL-6-induced STAT3 or STAT5 activation is a critical mechanism underlying PI3K inhibitor resistance in lymphoma, supporting the utility of IL-6 as an effective biomarker to predict therapeutic response to PI3K inhibitors.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Interleucina-6/metabolismo , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/metabolismo , Linfoma de Células T/tratamento farmacológico , Linfoma de Células T/metabolismo , Terapia de Alvo Molecular/métodos , Fosfatidilinositol 3-Quinases/metabolismo , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Interleucina-6/genética , Isoquinolinas/farmacologia , Inibidores de Janus Quinases/farmacologia , Linfoma de Células B/patologia , Linfoma de Células T/patologia , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Purinas/farmacologia , Pirimidinas/farmacologia , Quinazolinas/farmacologia , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT5/metabolismo , Transfecção , Proteínas Supressoras de Tumor/metabolismo
17.
Eur Radiol ; 29(10): 5539-5548, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30877463

RESUMO

OBJECTIVES: To test if adding permeability measurement to perfusion obtained from dynamic susceptibility contrast MRI (DSC-MRI) improves diagnostic performance in the differentiation of primary central nervous system lymphoma (PCNSL) from glioblastoma. MATERIALS AND METHODS: DSC-MRI was acquired in 145 patients with pathologically proven glioblastoma (n = 89) or PCNSL (n = 56). The permeability metrics of contrast agent extraction fraction (Ex), apparent permeability (Ka), and leakage-corrected perfusion of normalized cerebral blood volume (nCBVres) and cerebral blood flow (nCBFres) were derived from a tissue residue function. For comparison purposes, the leakage-corrected normalized CBV (nCBV) and relative permeability constant (K2) were also obtained using the established Weisskoff-Boxerman leakage correction method. The area under the receiver operating characteristics curve (AUC) and cross-validation were used to compare the diagnostic performance of the single DSC-MRI parameters with the performance obtained with the addition of permeability metrics. RESULTS: PCNSL demonstrated significantly higher permeability (Ex, p < .001) and lower perfusion (nCBVres, nCBFres, and nCBV, all p < .001) than glioblastoma. The combination of Ex and nCBVres showed the highest performance (AUC, 0.96; 95% confidence interval, 0.92-0.99) for differentiating PCNSL from glioblastoma, which was a significant improvement over the single perfusion (nCBV: AUC, 0.84; nCBVres: AUC, 0.84; nCBFres: AUC, 0.82; all p < .001) or Ex (AUC, 0.80; p < .001) parameters. CONCLUSIONS: Analysis of the combined permeability and perfusion metrics obtained from a single DSC-MRI acquisition improves the diagnostic value for differentiating PCNSL from glioblastoma in comparison with single-parameter nCBV analysis. KEY POINTS: • Permeability measurement can be calculated from DSC-MRI with a tissue residue function-based leakage correction. • Adding Exto CBV aids in the differentiation of PCNSL from glioblastoma. • CBV and Exmeasurements from DSC-MRI were highly reproducible.


Assuntos
Neoplasias do Sistema Nervoso Central/diagnóstico por imagem , Glioblastoma/diagnóstico por imagem , Linfoma não Hodgkin/diagnóstico por imagem , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/fisiopatologia , Neoplasias do Sistema Nervoso Central/fisiopatologia , Volume Sanguíneo Cerebral/fisiologia , Circulação Cerebrovascular/fisiologia , Meios de Contraste , Diagnóstico Diferencial , Feminino , Glioblastoma/fisiopatologia , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Linfoma não Hodgkin/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Perfusão , Permeabilidade , Curva ROC , Estudos Retrospectivos
18.
Glia ; 66(9): 1972-1987, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30043530

RESUMO

Spinocerebellar ataxia type 1 (SCA1) is a fatal, dominantly inherited neurodegenerative disease caused by the expansion of CAG repeats in the Ataxin-1 (ATXN1) gene. SCA1 is characterized by balance and coordination deficits due to the predominant loss of Purkinje neurons in the cerebellum. We previously demonstrated that cerebellar astrogliosis beings during the early stages of SCA1, prior to onset of motor deficits and loss of Purkinje neurons. We communicate here that cerebellar astrogliosis contributes to SCA1 pathogenesis in a biphasic, stage of disease dependent manner. We modulated astrogliosis by selectively reducing pro-inflammatory transcriptional regulator nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) signaling in astroglia via a Cre-lox mouse genetic approach. Our results indicate that inhibition of astroglial NF-κB signaling, prior to motor deficit onset, exacerbates disease severity. This is suggestive of a neuroprotective role mediated by astroglia during early stage SCA1. In contrast, inhibition of astroglial NF-κB signaling during late stage of disease ameliorated motor deficits, indicating a potentially harmful role of astroglia late in SCA1. These results indicate that astrogliosis may have a critical and dual role in disease. If so, our results imply that anti-inflammatory astroglia-based therapeutic approaches may need to consider disease progression to achieve therapeutic efficacy.


Assuntos
Astrócitos/fisiologia , Gliose/fisiopatologia , Ataxias Espinocerebelares/fisiopatologia , Animais , Astrócitos/patologia , Ataxina-1/genética , Ataxina-1/metabolismo , Cerebelo/patologia , Cerebelo/fisiopatologia , Modelos Animais de Doenças , Progressão da Doença , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/patologia , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/patologia , Microglia/fisiologia , Atividade Motora/fisiologia , NF-kappa B/metabolismo , Neurônios/patologia , Neurônios/fisiologia , Neuroproteção/fisiologia , Distribuição Aleatória , Ataxias Espinocerebelares/patologia
19.
Macromol Rapid Commun ; : e1800260, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29974539

RESUMO

A series of quinoxaline-based conjugated polymers, in which the electron-donating benzodithiophene (BDT) unit is linked to the electron-accepting 6,7-difluorinated quinoxaline (DFQ) derivatives by a thiophene bridge, is synthesized. To investigate their effects on the intrinsic properties of polymers, strong electron-withdrawing trifluoromethyl (CF3 ) groups were incorporated into the meta-position of the phenyl ring at the 2,3-positions of the DFQ unit of the reference polymer, labelled PEhB-FQx, to yield the target polymer PEhB-FQxCF3. In addition, the 2-ethylhexyloxy substituents on the BDT donor in PEhB-FQxCF3 are changed to the more planar 2-ethylhexyl thiophene units to produce another target polymer PThB-FQxCF3. Owing to the significant contributions of the CF3 moiety, PEhB-FQxCF3 exhibits quite discernible optical and electrochemical properties along with significant enhancement in photovoltaic performances compared to the reference polymer PEhB-FQx. Furthermore, the incorporation of the alkylthienyl side chains on the BDT moiety confers on the resultant PThB-FQxCF3 to possess the maximum power conversion efficiency of 7.26% with an open circuit voltage of 0.88 V, short-circuit current density of 12.20 mA cm-2 , and fill factor of 67.80%.

20.
Aesthet Surg J ; 38(5): 529-537, 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29300913

RESUMO

BACKGROUND: Calf contouring continues to be popular among Northeast Asians. Calf hypertrophy and distorted leg contours are stressful to many women. Several calf reduction techniques such as a selective neurectomy or calf muscle resection have been attempted, but have inconsistent results. OBJECTIVES: This study was designed to demonstrate improved outcomes when combining a selective neurectomy with simultaneous liposuction. METHODS: A total of 780 patients with hypertrophic calves underwent calf reduction from January 2002 to December 2010. Of these, 193 patients were treated by selective neurectomy with simultaneous liposuction. Calf hypertrophy with a circumference below 34 cm was defined as mild, calves with a circumference of 34 to 38 cm were defined as moderate, and a calf circumference above 38 cm was defined as severe. In all groups, patients whose pinch test was above 2 cm underwent a simultaneous liposuction. RESULTS: Twenty-eight cases (14.5%) were defined as mild, 72 (37.3%) were moderate, and 93 (48.2%) were severe. Over an average of 8.7 months of postoperative follow up, the reduction in calf circumference averaged 3.7 cm in the mild group (11.1%), 4.0 cm in the moderate group (10.7 %), and 4.3 cm in the severe group (10.7%). Overall, 97.5% of patients were satisfied with the results. There were no severe complications including functional problem of lower extremity reported. CONCLUSIONS: The shape, type, and fat distribution of the hypertrophic calves were considered in our patient analysis. A selective neurectomy with liposuction was performed on 193 patients. This technique allowed for a successful calf reduction and improved the patient's aesthetic satisfaction without any reported functional complications.


Assuntos
Denervação/métodos , Perna (Membro)/cirurgia , Lipectomia/métodos , Músculo Esquelético/cirurgia , Satisfação do Paciente , Adulto , Animais , Povo Asiático , Estética , Feminino , Humanos , Hipertrofia/cirurgia , Perna (Membro)/inervação , Perna (Membro)/patologia , Pessoa de Meia-Idade , Músculo Esquelético/inervação , Músculo Esquelético/patologia , Resultado do Tratamento
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