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1.
Proc Natl Acad Sci U S A ; 120(6): e2217607120, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36730189

RESUMO

The spleen clears altered red blood cells (RBCs) from circulation, contributing to the balance between RBC formation (erythropoiesis) and removal. The splenic RBC retention and elimination occur predominantly in open circulation where RBCs flow through macrophages and inter-endothelial slits (IESs). The mechanisms underlying and interconnecting these processes significantly impact clinical outcomes. In sickle cell disease (SCD), blockage of intrasplenic sickled RBCs is observed in infants splenectomized due to acute splenic sequestration crisis (ASSC). This life-threatening RBC pooling and organ swelling event is plausibly triggered or enhanced by intra-tissular hypoxia. We present an oxygen-mediated spleen-on-a-chip platform for in vitro investigations of the homeostatic balance in the spleen. To demonstrate and validate the benefits of this general microfluidic platform, we focus on SCD and study the effects of hypoxia on splenic RBC retention and elimination. We observe that RBC retention by IESs and RBC-macrophage adhesion are faster in blood samples from SCD patients than those from healthy subjects. This difference is markedly exacerbated under hypoxia. Moreover, the sickled RBCs under hypoxia show distinctly different phagocytosis processes from those non-sickled RBCs under hypoxia or normoxia. We find that reoxygenation significantly alleviates RBC retention at IESs, and leads to rapid unsickling and fragmentation of the ingested sickled RBCs inside macrophages. These results provide unique mechanistic insights into how the spleen maintains its homeostatic balance between splenic RBC retention and elimination, and shed light on how disruptions in this balance could lead to anemia, splenomegaly, and ASSC in SCD and possible clinical manifestations in other hematologic diseases.


Assuntos
Anemia Falciforme , Baço , Humanos , Microfluídica , Eritrócitos , Hipóxia
2.
Proc Natl Acad Sci U S A ; 119(30): e2208211119, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35858452

RESUMO

The dorsal root ganglia-localized voltage-gated sodium (Nav) channel Nav1.8 represents a promising target for developing next-generation analgesics. A prominent characteristic of Nav1.8 is the requirement of more depolarized membrane potential for activation. Here we present the cryogenic electron microscopy structures of human Nav1.8 alone and bound to a selective pore blocker, A-803467, at overall resolutions of 2.7 to 3.2 Å. The first voltage-sensing domain (VSDI) displays three different conformations. Structure-guided mutagenesis identified the extracellular interface between VSDI and the pore domain (PD) to be a determinant for the high-voltage dependence of activation. A-803467 was clearly resolved in the central cavity of the PD, clenching S6IV. Our structure-guided functional characterizations show that two nonligand binding residues, Thr397 on S6I and Gly1406 on S6III, allosterically modulate the channel's sensitivity to A-803467. Comparison of available structures of human Nav channels suggests the extracellular loop region to be a potential site for developing subtype-specific pore-blocking biologics.


Assuntos
Compostos de Anilina , Furanos , Canal de Sódio Disparado por Voltagem NAV1.7 , Bloqueadores do Canal de Sódio Disparado por Voltagem , Regulação Alostérica , Compostos de Anilina/química , Compostos de Anilina/farmacologia , Microscopia Crioeletrônica , Furanos/química , Furanos/farmacologia , Humanos , Potenciais da Membrana , Canal de Sódio Disparado por Voltagem NAV1.7/química , Domínios Proteicos , Bloqueadores do Canal de Sódio Disparado por Voltagem/química , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacologia
3.
J Am Chem Soc ; 146(11): 7868-7874, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38457655

RESUMO

Sulfate crystals are often criticized for their low birefringence. The small anisotropic SO4 group is becoming the biggest bottleneck hindering the application of sulfates in optical functional materials. In this study, we report a new method to significantly enhance the birefringence of sulfates. The title compound increases the birefringence recording of sulfates to 0.542@546 nm, which is significantly larger than that of the commercial birefringent crystal of TiO2 (0.306@546.1 nm). At the infrared wavelength, the birefringence of Hg4(Te2O5)(SO4) can be up to 0.400@1064 nm, which is also much larger than the infrared birefringent crystal of YVO4 (0.209@1064 nm). In addition, it also has a wide transparency range, high thermal stability, and excellent environmental stability, making it a potential birefringent material. Hg4(Te2O5)(SO4) features a novel two-dimensional layered structure composed of [Hg4(Te2O5)]2+ layers separated by isolated (SO4)2- tetrahedra. This compound was designed by introducing a highly selective cation in a tellurite sulfate system. The low valence low coordination cations connect with tellurite groups only, making the sulfate isolated in the structure. The steric repulsive action of the isolated SO4 tetrahedra may regulate the linear and lone pair groups arranged in a way that favors large birefringence. This method can be proven by theoretical calculations. PAWED studies showed that the large birefringence originated from the synergistic effect of (Hg2O2)2-, (Te2O5)2-, and (SO4)2- units, with a contribution ratio of 42.17, 37.92, and 19.88%, respectively. Our work breaks the limitation of low birefringence in sulfates and opens up new possibilities for their application as birefringent crystals.

4.
Inorg Chem ; 63(9): 4011-4016, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38363859

RESUMO

Exploring new material systems is a highly significant task in the field of inorganic chemistry. A new mixed-valent selenium compound, Hg3Se(SeO3)(SO4), was successfully synthesized through in situ reactions. This compound exhibits a novel three-dimensional structure composed of Hg3Se(SO4) layers bridged by SeO3 trigonal pyramids. It is the first structure containing (SeO3)2-, (SO4)2-, and Se2- simultaneously. In addition, Hg3Se(SeO3)(SO4) possesses a wide bandgap (3.5 eV), moderate birefringence (Cal:0.064@546 nm, Exp:0.069@546 nm), a high laser-induced damage threshold (23.35 MW cm-2), and a wide transmittance window (0.28-6.6 µm). Our work demonstrates that mixed-valent (+4, -2) selenite selenide can be potential optical materials for the mid-infrared region.

5.
Inorg Chem ; 63(13): 6067-6074, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38489513

RESUMO

The first examples of alkali metal selenite sulfates, namely, Na8(SeO3)(SO4)3 (1), Na2(H2SeO3)(SO4) (2), and K4(H2SeO3)(HSO4)2(SO4) (3), were successfully synthesized by hydrothermal reactions. Their structures display three different zero-dimensional configurations composed of isolated sulfate tetrahedra and selenite groups separated by alkali metals. Na8(SeO3)(SO4)3 (1) features a noncentrosymmetric structure, while Na2(H2SeO3)(SO4) (2) and K4(H2SeO3)(HSO4)2(SO4) (3) are centrosymmetric. Powder second-harmonic-generation measurements revealed that Na8(SeO3)(SO4)3 (1) shows a phase-matchable SHG intensity about 1.2 times that of KDP. UV-vis-NIR diffuse reflectance spectroscopic analysis indicated that Na8(SeO3)(SO4)3 (1) has a short UV cutoff edge and a large optical band gap, which makes it a possible UV nonlinear optical material. Theoretical calculations revealed that the birefringence of Na8(SeO3)(SO4)3 (1) is 0.041 at 532 nm, which is suitable for phase-matching condition. This work provides a good experimental foundation for the exploration of new UV nonlinear crystals in an alkali metal selenite sulfate system.

6.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33762307

RESUMO

Understanding the mechanics of blood flow is necessary for developing insights into mechanisms of physiology and vascular diseases in microcirculation. Given the limitations of technologies available for assessing in vivo flow fields, in vitro methods based on traditional microfluidic platforms have been developed to mimic physiological conditions. However, existing methods lack the capability to provide accurate assessment of these flow fields, particularly in vessels with complex geometries. Conventional approaches to quantify flow fields rely either on analyzing only visual images or on enforcing underlying physics without considering visualization data, which could compromise accuracy of predictions. Here, we present artificial-intelligence velocimetry (AIV) to quantify velocity and stress fields of blood flow by integrating the imaging data with underlying physics using physics-informed neural networks. We demonstrate the capability of AIV by quantifying hemodynamics in microchannels designed to mimic saccular-shaped microaneurysms (microaneurysm-on-a-chip, or MAOAC), which signify common manifestations of diabetic retinopathy, a leading cause of vision loss from blood-vessel damage in the retina in diabetic patients. We show that AIV can, without any a priori knowledge of the inlet and outlet boundary conditions, infer the two-dimensional (2D) flow fields from a sequence of 2D images of blood flow in MAOAC, but also can infer three-dimensional (3D) flow fields using only 2D images, thanks to the encoded physics laws. AIV provides a unique paradigm that seamlessly integrates images, experimental data, and underlying physics using neural networks to automatically analyze experimental data and infer key hemodynamic indicators that assess vascular injury.


Assuntos
Inteligência Artificial , Velocidade do Fluxo Sanguíneo , Retinopatia Diabética/diagnóstico , Imageamento Tridimensional/métodos , Dispositivos Lab-On-A-Chip , Microaneurisma/diagnóstico , Vasos Retinianos/fisiopatologia , Reologia/métodos , Simulação por Computador , Retinopatia Diabética/fisiopatologia , Hemodinâmica , Humanos , Microaneurisma/fisiopatologia , Técnicas Analíticas Microfluídicas , Fluxo Sanguíneo Regional
7.
Proc Natl Acad Sci U S A ; 118(7)2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33531347

RESUMO

Cell-cell adhesions are often subjected to mechanical strains of different rates and magnitudes in normal tissue function. However, the rate-dependent mechanical behavior of individual cell-cell adhesions has not been fully characterized due to the lack of proper experimental techniques and therefore remains elusive. This is particularly true under large strain conditions, which may potentially lead to cell-cell adhesion dissociation and ultimately tissue fracture. In this study, we designed and fabricated a single-cell adhesion micro tensile tester (SCAµTT) using two-photon polymerization and performed displacement-controlled tensile tests of individual pairs of adherent epithelial cells with a mature cell-cell adhesion. Straining the cytoskeleton-cell adhesion complex system reveals a passive shear-thinning viscoelastic behavior and a rate-dependent active stress-relaxation mechanism mediated by cytoskeleton growth. Under low strain rates, stress relaxation mediated by the cytoskeleton can effectively relax junctional stress buildup and prevent adhesion bond rupture. Cadherin bond dissociation also exhibits rate-dependent strengthening, in which increased strain rate results in elevated stress levels at which cadherin bonds fail. This bond dissociation becomes a synchronized catastrophic event that leads to junction fracture at high strain rates. Even at high strain rates, a single cell-cell junction displays a remarkable tensile strength to sustain a strain as much as 200% before complete junction rupture. Collectively, the platform and the biophysical understandings in this study are expected to build a foundation for the mechanistic investigation of the adaptive viscoelasticity of the cell-cell junction.


Assuntos
Junções Intercelulares/metabolismo , Estresse Mecânico , Caderinas/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Citoesqueleto/metabolismo , Elasticidade , Humanos , Junções Intercelulares/química , Viscosidade
8.
Eur Arch Otorhinolaryngol ; 281(3): 1425-1434, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37995006

RESUMO

OBJECTIVE: To analyze the interrelation between radiation dose and radiation-induced nasopharyngeal ulcer (RINU) in locoregional recurrent nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT). METHODS: Clinical data were collected from 363 patients with locoregional recurrent NPC who received re-irradiated with definitive IMRT from 2009 to 2017. Twenty-nine patients were diagnosed with RINU. Univariate and multivariate analyses were used to re-evaluate the first and second radiotherapy plans and to identify predictive dosimetric factors. RESULTS: All dosimetric parameters were notably associated with the progression to RINU (p < 0.01) using paired samples Wilcoxon signed rank tests. Multivariate analysis showed that EQD2_ [Formula: see text]D80 (dose for 80 percent volume of the unilateral nasopharynx lesion) was an independent prognostic factor for RINU (p = 0.001). The area under the ROC curve for EQD2_ [Formula: see text]D80 was 0.846 (p < 0.001), and the cutoff point of 137.035 Gy could potentially be the dose tolerance of the nasopharyngeal mucosa. CONCLUSIONS: The sum of equivalent dose in 2 Gy fractions (EQD2) in the overlapping volumes between initial and re-irradiated nasopharyngeal mucosal tissue can be effective in predicting the hazard of developing RINU in NPC patients undergoing radical re­irradiation with IMRT and we propose a EQD2_ [Formula: see text]D80 threshold of 137.035 Gy for the nasopharynx.


Assuntos
Neoplasias Nasofaríngeas , Lesões por Radiação , Radiodermite , Radioterapia de Intensidade Modulada , Reirradiação , Humanos , Carcinoma Nasofaríngeo/radioterapia , Radioterapia de Intensidade Modulada/efeitos adversos , Neoplasias Nasofaríngeas/patologia , Úlcera/etiologia , Dosagem Radioterapêutica , Lesões por Radiação/etiologia , Estudos Retrospectivos , Nasofaringe/patologia , Radiodermite/etiologia
9.
J Am Chem Soc ; 145(44): 24416-24424, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37881867

RESUMO

An unusual O/F ordered d0 transition metal fluoroantimonite, namely, K2SbMoO2F7, has been created by the cationic size effect of alkali metals. It features the largest birefringence of 0.220@550 nm among inorganic antimonites with a halogen element, which is an order of magnitude larger than the disordered A2SbMoO2F7 (A = Rb, Cs). These three new compounds exhibit two different structures, although all of the structures were made of [SbMoO2F7]2- chains formed by SbF5 square pyramids and MoO2F4 octahedrons. A transparent single crystal of K2SbMoO2F7 with dimensions of 7.0 × 5.0 × 1.0 mm3 has been successfully grown by the aqueous solution volatilization method. The UV-vis-MIR transmission spectrum showed that K2SbMoO2F7 can display excellent transmittance in the range of 0.5-5.0 µm and 6.0-9.8 µm, indicating its application potential as a birefringent material in the mid infrared band. This work offers a fresh approach to the design and synthesis of mid infrared birefringent materials.

10.
Cell Mol Neurobiol ; 43(5): 1957-1974, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36006573

RESUMO

After restoration of spontaneous circulation (ROSC) following cardiac arrest, complements can be activated and excessive autophagy can contribute to the brain ischemia-reperfusion (I/R) injury. Mild hypothermia (HT) protects against brain I/R injury after ROSC, but the mechanisms have not been fully elucidated. Here, we found that HT significantly inhibited the increases in serum NSE, S100ß, and C5a, as well as neurologic deficit scores, TUNEL-positive cells, and autophagic vacuoles in the pig brain cortex after ROSC. The C5a receptor 1 (C5aR1) mRNA and the C5a, C5aR1, Beclin 1, LC3-II, and cleaved caspase-3 proteins were significantly increased, but the P62 protein and the PI3K/Akt/mTOR pathway-related proteins were significantly reduced in pigs after ROSC or neuronal oxygen-glucose deprivation/reoxygenation. HT could significantly attenuate the above changes in NT-treated neurons. Furthermore, C5a treatment induced autophagy and apoptosis and reduced the PI3K/Akt/mTOR pathway-related proteins in cultured neurons, which could be reversed by C5aR1 antagonist PMX205. Our findings demonstrated that C5a could bind to C5aR1 to induce neuronal autophagy during the brain I/R injury, which was associated with the inhibited PI3K/Akt/mTOR pathway. HT could inhibit C5a-induced neuronal autophagy by regulating the C5a-C5aR1 interaction and the PI3K/Akt/mTOR pathway, which might be one of the neuroprotective mechanisms underlying I/R injury. The C5a receptor 1 (C5aR1) mRNA and the C5a, C5aR1, Beclin 1, LC3-II, and cleaved caspase-3 proteins were significantly increased, but the P62 protein and the PI3K/Akt/mTOR pathway-related proteins were significantly reduced in pigs after ROSC or neuronal oxygen-glucose deprivation/reoxygenation. Mild hypothermia (HT) could significantly attenuate the above changes in NT-treated neurons. Furthermore, C5a treatment induced autophagy and apoptosis and reduced the PI3K/Akt/mTOR pathway-related proteins in cultured neurons, which could be reversed by C5aR1 antagonist PMX205. Proposed mechanism by which HT protects against brain I/R injury by repressing C5a-C5aR1-induced excessive autophagy. Complement activation in response to brain I/R injury generates C5a that can interact with C5aR1 to inactivate mTOR, probably through the PI3K-AKT pathway, which can finally lead to autophagy activation. The excessively activated autophagy ultimately contributes to cell apoptosis and brain injury. HT may alleviate complement activation and then reduce C5a-induced autophagy to protect against brain I/R injury. HT, mild hypothermia; I/R, ischemia reperfusion.


Assuntos
Parada Cardíaca , Hipotermia , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Animais , Suínos , Caspase 3/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Hipotermia/metabolismo , Proteína Beclina-1/metabolismo , Receptor da Anafilatoxina C5a/metabolismo , Fármacos Neuroprotetores/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Encéfalo/metabolismo , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/metabolismo , Oxigênio/metabolismo , Parada Cardíaca/metabolismo , Parada Cardíaca/terapia , Autofagia , RNA Mensageiro/metabolismo , Glucose/metabolismo
11.
Inorg Chem ; 62(22): 8494-8499, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37222710

RESUMO

The exploration of novel inorganic tellurites is significant because of their promising applications in nonlinear-optical materials and birefringent materials. Herein, three new aluminum/gallium tellurites, namely, NaAl(Te4O10) (1), AgAl(Te4O10) (2), and K2Ga2(HTe6O16)(HTeO3) (3), have been successfully obtained by mild hydrothermal reactions. The isostructural compounds 1 and 2 contain the Te3O8 trimer, while compound 3 contains an unprecedented Te6O16 hexamer. Notably, all three compounds exhibit large birefringence values of over 0.1 at 532 nm, which are currently the largest reported birefringence values among tellurium(IV) oxides without additional anionic groups.

12.
Cryobiology ; 110: 49-55, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36509162

RESUMO

The outcome of cardiac arrest is worse when there is fever after spontaneous circulation is restored (ROSC). The purpose of this study was to investigate the mechanism of post-ROSC cardiac dysfunction after hyperthermia treatment and the effects of temperature control. Twenty-four male Bama minipigs were randomized into 3 groups (8 per group): CPR + controlled normothermia (CN), CPR + hyperthermia (HT), and CPR + therapeutic mild hypothermia (TMH). Defibrillation was given to pigs with ventricular fibrillation after 8 min of untreated fibrillation. Subsequently, these animals received the post-ROSC treatments of hyperthermia (38 °C), controlled normothermia (37 °C) or hypothermia (33 °C) according to the groups. Hemodynamic parameters, left ventricular ejection fraction, blood samples and myocardial tissues were assessed. At 24 h after the post-ROSC treatments, the pigs treated with hyperthermia showed increments in heart rate and plasma cardiac troponin I, and decreases in mean arterial pressure, cardiac index, and left ventricular ejection fraction, compared to those with the controlled normothermia pigs. However, the deterioration of the above parameters can be attenuated by TMH. The pigs in the TMH group also had a reduced percentage of apoptotic cardiomyocytes, an increased anti-apoptotic Bcl-2/Bax ratio and a decreased caspase-3 activity in myocardium, as compared with both controlled normothermia and hyperthermia pigs. In conclusion, hyperthermia is associated with a worse myocardial dysfunction. TMH improves hyperthermia-induced myocardial dysfunction by attenuating apoptosis in a porcine model of cardiac arrest.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca , Hipertermia Induzida , Hipotermia Induzida , Hipotermia , Suínos , Animais , Masculino , Volume Sistólico , Hipotermia/terapia , Temperatura , Porco Miniatura , Função Ventricular Esquerda , Criopreservação/métodos
13.
Appl Opt ; 62(25): 6680-6688, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37706800

RESUMO

In recent years, biomimetic polarization navigation has become a research hotspot in navigation fields because of its autonomy and concealment. Existing point-source polarization navigation sensors mainly use a logarithmic amplifier as the arithmetic unit to obtain polarization information. However, these sensors suffer from zero drift and low detection accuracy, which limits their application range. To address the above issues, a polarization navigation sensor based on a differential amplifier is designed as the operational unit. Based on the change of the arithmetic unit of the polarization signal, the algorithm for calculating the heading angle of the sensor is improved. The results of the orientation experiments with the designed sensor in clear weather indicate that the orientation error is ±1.243∘, and the standard deviation is 0.351°. The polarization navigation sensor can extract polarized light information and calculate the heading without accumulation of errors over time accurately and achieves good real-time performance.

14.
Sensors (Basel) ; 23(13)2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37447698

RESUMO

A polarized light sensor is applied to the front-end detection of a biomimetic polarized light navigation system, which is an important part of analyzing the atmospheric polarization mode and realizing biomimetic polarized light navigation, having received extensive attention in recent years. In this paper, biomimetic polarized light navigation in nature, the mechanism of polarized light navigation, point source sensor, imaging sensor, and a sensor based on micro nano machining technology are compared and analyzed, which provides a basis for the optimal selection of different polarized light sensors. The comparison results show that the point source sensor can be divided into basic point source sensor with simple structure and a point source sensor applied to integrated navigation. The imaging sensor can be divided into a simple time-sharing imaging sensor, a real-time amplitude splitting sensor that can detect images of multi-directional polarization angles, a real-time aperture splitting sensor that uses a light field camera, and a real-time focal plane light splitting sensor with high integration. In recent years, with the development of micro and nano machining technology, polarized light sensors are developing towards miniaturization and integration. In view of this, this paper also summarizes the latest progress of polarized light sensors based on micro and nano machining technology. Finally, this paper summarizes the possible future prospects and current challenges of polarized light sensor design, providing a reference for the feasibility selection of different polarized light sensors.


Assuntos
Biomimética , Refração Ocular
15.
Angew Chem Int Ed Engl ; 62(17): e202301420, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-36847469

RESUMO

It is a great challenge to develop UV nonlinear optical (NLO) material due to the demanding conditions of strong second harmonic generation (SHG) intensity and wide band gap. The first ultraviolet NLO selenite material, Y3 F(SeO3 )4 , has been obtained by control of the fluorine content in a centrosymmetric CaYF(SeO3 )2 . The two new compounds represent similar 3D structures composed of 3D yttrium open frameworks strengthened by selenite groups. CaYF(SeO3 )2 has a large birefringence (0.138@532 nm and 0.127@1064 nm) and a wide optical band gap (5.06 eV). The non-centrosymmetric Y3 F(SeO3 )4 can exhibit strong SHG intensity (5.5×KDP@1064 nm), wide band gap (5.03 eV), short UV cut-off edge (204 nm) and high thermal stability (690 °C). So, Y3 F(SeO3 )4 is a new UV NLO material with excellent comprehensive properties. Our work shows that it is an effective method to develop new UV NLO selenite material by fluorination control of the centrosymmetric compounds.

16.
Small ; 18(6): e2104470, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34984816

RESUMO

Extracellular vesicles (EVs) are recognized as next generation diagnostic biomarkers due to their disease-specific biomolecular cargoes and importance in cell-cell communications. A major bottleneck in EV sample preparation is the inefficient and laborious isolation of nanoscale EVs (≈50-200 nm) from endogenous proteins in biological samples. Herein, a unique microfluidic platform is reported for EV-protein fractionation based on the principle of size exclusion chromatography (SEC). Using a novel rapid (≈20 min) replica molding technique, a fritless microfluidic SEC device (µSEC) is fabricated using thiol-ene polymer (UV glue NOA81, Young's modulus ≈1 GPa) for high pressure (up to 6 bar) sample processing. Controlled on-chip nanoliter sample plug injection (600 nL) using a modified T-junction injector is first demonstrated with rapid flow switching response time (<1.5 s). Device performance is validated using fluorescent nanoparticles (50 nm), albumin, and breast cancer cells (MCF-7)-derived EVs. As a proof-of-concept for clinical applications, EVs are directly isolated from undiluted human platelet-poor plasma using µSEC and show distinct elution profiles between EVs and proteins based on nanoparticle particle analysis (NTA), Western blot and flow cytometry analysis. Overall, the optically transparent µSEC can be readily automated and integrated with EV detection assays for EVs manufacturing and clinical diagnostics.


Assuntos
Vesículas Extracelulares , Microfluídica , Proteínas Sanguíneas/metabolismo , Cromatografia em Gel , Vesículas Extracelulares/metabolismo , Humanos , Plasma
17.
Acc Chem Res ; 54(12): 2775-2783, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34043910

RESUMO

ConspectusSecond-harmonic-generation (SHG) causes the frequency doubling of light, which is very useful for generating high-energy lasers with specific wavelengths. Noncentrosymmetry (NCS) is the first requirement for an SHG process because the SHG coefficient is zero (χ2 = 0) in all centrosymmetric structures. At this stage, developing novel NCS crystals is a crucial scientific topic. Assembling polar units in an addictive fashion can facilely form NCS crystals with outstanding SHG performance. In this way, our group has obtained many different NCS crystals with extremely large SHG intensities (>5 × KDP or 1 × KTP). In this Account, we first provide a brief review of the development of SHG materials and concisely highlight the features of the excellent SHG materials. Then, we present four facile and rational molecular design strategies: (1) Traditional BO33--based crystals feature short absorption edges but usually suffer from relatively weak SHG performance (<5 × KDP). The combination of two types of pure π-conjugated anions (BO33- and NO3-) in a parallel fashion in the same compound has afforded a metal borate nitrate with a strong SHG effect. (2) To overcome the problems of the weak SHG effect and small birefringence in the less anisotropic QO4-based compounds, highly polarizable cations such as Hg2+ and Bi3+ are introduced into these systems, which greatly enhances both SHG effects and birefringence. (3) Iodate anions can be condensed into polynuclear iodate anions with a higher density of I5+ per unit cell, hence polyiodate anions can serve as excellent SHG-active groups. We developed a novel synthesis method for hydrothermal reactions under a phosphoric acid medium and obtained a series of metal polyiodates with strong SHG effects. In addition, as the number of iodate groups increases, the structural configuration of the polyiodate anion changes from linear to bent. (4) We introduce the concept of aliovalent substitution which features site-to-site atomic displacement at the structural level. Such aliovalent substitution led to new materials that have the same chemical stoichiometries or structural features as their parent compounds. Thus, aliovalent substitution can provide more experimental opportunities and afford new high-performance SHG materials. The introduction of a fluoride anion and the replacement of metal cations in the MO6 octahedron can result in new metal iodates with balanced properties including a large SHG effect, a wide band gap, and a high laser-induced damage threshold (LIDT) value. Finally, we briefly discuss several problems associated with the studies of SHG materials and give some prospects for SHG materials in the future.

18.
BMC Cancer ; 22(1): 1083, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36271328

RESUMO

BACKGROUND: To review our long-term clinical experience, analyze the failure patterns, and give suggestions for target volume delineation of carcinoma showing thymus-like differentiation (CASTLE) treated with intensity-modulated radiotherapy (IMRT). METHODS: From April 2008 to May 2019, 30 patients with CASTLE treated by postoperative or radical IMRT in our center were retrospectively reviewed. A total dose of 56-60 Gy in 28-30 fractions was prescribed to patients without residual disease and 66 Gy in 33 fractions for patients with residual or unresectable disease. Survival rates were calculated using the Kaplan-Meier method. Treatment-related toxicities were graded by National Cancer Institute Common Toxicity Criteria (NCI-CTC) version 4.0. RESULTS: Among the 30 patients, 12 (40%) received partial resection or biopsy. Lateral lymph node metastasis was observed in 7 (23.3%) patients. During follow-up, regional lymph node recurrence occurred in 2 patients and distant metastasis in 5 patients. With a median follow-up time of 63.5 months, the 5-year local recurrence-free survival (LRFS), regional recurrence-free survival (RRFS), distant metastasis-free survival (DMFS), overall survival (OS) and progression-free survival (PFS) rates were 100, 88.9, 78.9, 93.1 and 78.9%, respectively. For patients with no lateral neck node metastasis, prophylactic radiotherapy for lateral neck nodal regions failed to improve RRFS (p = 0.381) and OS (p = 0.153). CONCLUSION: Distant metastasis was the major failure pattern for CASTLE after surgery and IMRT. For patients with no lateral neck node metastasis, the omission of irradiation for lateral neck nodal regions seems to be safe and feasible.


Assuntos
Carcinoma , Radioterapia de Intensidade Modulada , Humanos , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Carcinoma/patologia , Planejamento da Radioterapia Assistida por Computador/métodos , Metástase Linfática/radioterapia
19.
Inorg Chem ; 61(12): 4801-4805, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35285612

RESUMO

The first examples of zirconium fluoroantimonites, namely, K3ZrF4(SbF4)(SbF5) and K8(ZrF6)(Sb2Zr2F20), have been successfully synthesized by facial hydrothermal reactions. K3ZrF4(SbF4)(SbF5) features a unique 1D (ZrSb2F13)3- double-chain structure, while K8(ZrF6)(Sb2Zr2F20) displays a special 0D construction composed of Zr2Sb2F20 tetranuclear clusters and isolated ZrF6 octahedra. The two fluorides can exhibit a broad transparency range with almost no absorption peaks from ultraviolet to near-IR. For K8(ZrF6)(Sb2Zr2F20), a phase transformation was found before decomposition. The band structures, density of states, and linear-optical properties for the title compounds were also obtained.

20.
Inorg Chem ; 61(5): 2686-2694, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35068146

RESUMO

A new phase-matchable nonlinear-optical material, Na3Ti3O3(SeO3)4F, has been achieved by a facile hydrothermal reaction. The anionic skeleton displays a honeycombed 3D structure with Ti6Se6 12-member polyhedral ring tunnels along the c axis. Na3Ti3O3(SeO3)4F presents a strong second-harmonic-generation (SHG) response of about 6 × KDP, which is twice that of its isostructural Ag compound. Interestingly, the band gap of Na3Ti3O3(SeO3)4F is also broader than that of the isomorph. Also, the powder laser-induced damage threshold of Na3Ti3O3(SeO3)4F is even 5.5 times larger than that of Ag3Ti3O3(SeO3)4F. Theoretical calculations revealed that the fully filled Ag 4d and empty Ag 5s states have made the difference in the band gap and SHG response of the two isostructural compounds. Our work has provided a practical way of improving the SHG efficiency and band gap simultaneously, which is usually considered to be a pair of negatively correlated parameters.

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