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1.
Cell ; 184(8): 2020-2032.e14, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33861963

RESUMO

Interspecies chimera formation with human pluripotent stem cells (hPSCs) represents a necessary alternative to evaluate hPSC pluripotency in vivo and might constitute a promising strategy for various regenerative medicine applications, including the generation of organs and tissues for transplantation. Studies using mouse and pig embryos suggest that hPSCs do not robustly contribute to chimera formation in species evolutionarily distant to humans. We studied the chimeric competency of human extended pluripotent stem cells (hEPSCs) in cynomolgus monkey (Macaca fascicularis) embryos cultured ex vivo. We demonstrate that hEPSCs survived, proliferated, and generated several peri- and early post-implantation cell lineages inside monkey embryos. We also uncovered signaling events underlying interspecific crosstalk that may help shape the unique developmental trajectories of human and monkey cells within chimeric embryos. These results may help to better understand early human development and primate evolution and develop strategies to improve human chimerism in evolutionarily distant species.


Assuntos
Quimerismo , Embrião de Mamíferos/citologia , Células-Tronco Pluripotentes/citologia , Animais , Blastocisto/citologia , Blastocisto/metabolismo , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Embrião de Mamíferos/metabolismo , Feminino , Humanos , Macaca fascicularis , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/transplante , RNA-Seq , Análise de Célula Única , Transcriptoma
3.
Nature ; 617(7961): 524-528, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37198312

RESUMO

As an atom-efficient strategy for the large-scale interconversion of olefins, heterogeneously catalysed olefin metathesis sees commercial applications in the petrochemical, polymer and speciality chemical industries1. Notably, the thermoneutral and highly selective cross-metathesis of ethylene and 2-butenes1 offers an appealing route for the on-purpose production of propylene to address the C3 shortfall caused by using shale gas as a feedstock in steam crackers2,3. However, key mechanistic details have remained ambiguous for decades, hindering process development and adversely affecting economic viability4 relative to other propylene production technologies2,5. Here, from rigorous kinetic measurements and spectroscopic studies of propylene metathesis over model and industrial WOx/SiO2 catalysts, we identify a hitherto unknown dynamic site renewal and decay cycle, mediated by proton transfers involving proximal Brønsted acidic OH groups, which operates concurrently with the classical Chauvin cycle. We show how this cycle can be manipulated using small quantities of promoter olefins to drastically increase steady-state propylene metathesis rates by up to 30-fold at 250 °C with negligible promoter consumption. The increase in activity and considerable reduction of operating temperature requirements were also observed on MoOx/SiO2 catalysts, showing that this strategy is possibly applicable to other reactions and can address major roadblocks associated with industrial metathesis processes.

4.
Small ; 20(12): e2306991, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939298

RESUMO

The shuttle effect, which causes the loss of active sulfur, passivation of lithium anode, and leads to severe capacity attenuation, is currently the main bottleneck for lithium-sulfur batteries. Recent studies have disclosed that molybdenum compounds possess exceptional advantages as a polar substrate to immobilize and catalyze lithium polysulfide such as high conductivity and strong sulfiphilicity. However, these materials show incomplete contact with sulfur/polysulfides, which causes uneven redox conversion of sulfur and results in poor rate performance. Herein, a new type of 2D nano-channeled molybdenum compounds (2D-MoNx) via the 2D organic-polyoxometalate superstructure for accelerating interfacial polysulfide catalysis toward high-performance lithium-sulfur batteries is reported. The 2D-MoNx shows well-interlinked nano-channels, which increase the reactive interface and contact surface with polysulfides. Therefore, the battery equipped with 2D-MoNx displays a high discharge capacity of 912.7 mAh g-1 at 1 C and the highest capacity retention of 523.7 mAh g-1 after 300 cycles. Even at the rate of 2 C, the capacity retention can be maintained at 526.6 mAh g-1 after 300 cycles. This innovative nano-channel and interfacial design of 2D-MoNx provides new nanostructures to optimize the sulfur redox chemistry and eliminate the shuttle effect of polysulfides.

5.
Mol Pharm ; 21(7): 3407-3415, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822792

RESUMO

Transarterial radioembolization (TARE) is a highly effective localized radionuclide therapy that has been successfully used to treat hepatocellular carcinoma (HCC). Extensive research has been conducted on the use of radioactive microspheres (MSs) in TARE, and the development of ideal radioactive MSs is crucial for clinical trials and patient treatment. This study presents the development of a radioactive MS for TARE of HCC. These MSs, referred to as 177Lu-MS@PLGA, consist of poly(lactic-co-glycolic acid) (PLGA) copolymer and radioactive silica MSs, labeled with 177Lu and then coated with PLGA. It has an extremely high level of radiostability. Cellular experiments have shown that it can cause DNA double-strand breaks, leading to cell death. In vivo radiostability of 177Lu-MS@PLGA is demonstrated by microSPECT/CT imaging. In addition, the antitumor study has shown that TARE of 177Lu-MS@PLGA can effectively restrain tumor growth without harmful side effects. Thus, 177Lu-MS@PLGA exhibits significant potential as a radioactive MS for the treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Embolização Terapêutica , Neoplasias Hepáticas , Lutécio , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Radioisótopos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/radioterapia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Animais , Humanos , Camundongos , Lutécio/química , Radioisótopos/química , Radioisótopos/administração & dosagem , Embolização Terapêutica/métodos , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C , Camundongos Nus , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Angew Chem Int Ed Engl ; 63(25): e202404019, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38622071

RESUMO

Accelerating sulfur conversion catalysis to alleviate the shuttle effect has become a novel paradigm for effective Li-S batteries. Although nitrogen-coordinated metal single-atom (M-N4) catalysts have been investigated, further optimizing its utilization rate and catalytic activities is urgently needed for practical applications. Inspired by the natural alveoli tissue with interconnected structure and well-distributed enzyme catalytic sites on the wall for the simultaneously fast diffusion and in situ catalytic conversion of substrates, here, we proposed the controllable synthesis of bioinspired carbon cathode with interconnected porous structure and asymmetric coordinated V-S1N3 sites for efficient and stable Li-S batteries. The enzyme-mimetic V-S1N3 shows asymmetric electronic distribution and high tunability, therefore enhancing in situ polysulfide conversion activities. Experimental and theoretical results reveal that the high charge asymmetry degree and large atom radius of S in V-S1N3 result in sloping adsorption for polysulfide, thereby exhibiting low thermodynamic energy barriers and long-range stability (0.076 % decay over 600 cycles).

7.
J Am Chem Soc ; 145(23): 12651-12662, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37256723

RESUMO

The olefin metathesis activity of silica-supported molybdenum oxides depends strongly on metal loading and preparation conditions, indicating that the nature and/or amounts of the active sites vary across compositionally similar catalysts. This is illustrated by comparing Mo-based (pre)catalysts prepared by impregnation (2.5-15.6 wt % Mo) and a model material (2.3 wt % Mo) synthesized via surface organometallic chemistry (SOMC). Analyses of FTIR, UV-vis, and Mo K-edge X-ray absorption spectra show that these (pre)catalysts are composed predominantly of similar isolated Mo dioxo sites. However, they exhibit different reaction properties in both liquid and gas-phase olefin metathesis with the SOMC-derived catalyst outperforming a classical catalyst of a similar Mo loading by ×1.5-2.0. Notably, solid-state 95Mo NMR analyses leveraging state-of-the-art high-field (28.2 T) measurement conditions resolve four distinct surface Mo dioxo sites with distributions that depend on the (pre)catalyst preparation methods. The intensity of a specific deshielded 95Mo NMR signal, which is most prominent in the SOMC-derived catalyst, is linked to reducibility and catalytic activity. First-principles calculations show that 95Mo NMR parameters directly manifest the local strain and coordination environment: acute (SiO-Mo(O)2-OSi) angles and low coordination numbers at Mo lead to highly deshielded 95Mo chemical shifts and small quadrupolar coupling constants, respectively. Natural chemical shift analyses relate the 95Mo NMR signature of strained species to low LUMO energies, which is consistent with their high reducibility and corresponding reactivity. The 95Mo chemical shifts of supported Mo dioxo sites are thus linked to their specific electronic structures, providing a powerful descriptor for their propensity toward reduction and formation of active sites.

8.
Eur Spine J ; 32(1): 301-312, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36380008

RESUMO

PURPOSE: Both erector spinae plane block and wound infiltration are used to improve analgesia following spinal fusion surgery. Herein, we compared the analgesic effect of bilateral erector spinae plane block with wound infiltration in this patient population. METHODS: In this randomized trial, 60 patients scheduled for elective open posterior lumbar interbody fusion surgery were randomized to receive either ultrasound-guided bilateral erector spinae plane block before incision (n = 30) or wound infiltration at the end of surgery (n = 30). Both groups received standardized general anesthesia and postoperative analgesia, including patient-controlled analgesia with sufentanil and no background infusion. Opioid consumption and pain intensity were assessed at 2, 6, 12, 24, and 48 h after surgery. The primary outcome was cumulative opioid consumption within 24 h after surgery. RESULTS: All 60 patients were included in the intention-to-treat analysis. The equivalent dose of sufentanil consumption within 24 h was significantly lower in patients given erector spinae plane block (median 11 µg, interquartile range 5-16) than in those given wound infiltration (20 µg, 10 to 43; median difference - 10 µg, 95% CI - 18 to - 3, P = 0.007). The cumulative number of demanded PCA boluses was significantly lower with erector spinae plane block at 6 h (median difference - 2, 95% CI - 3 to 0, P = 0.006), 12 h (- 3, 95% CI - 6 to - 1, P = 0.002), and 24 h (- 5, 95% CI - 8 to - 2, P = 0.005) postoperatively. The proportion given rescue analgesia was also significantly lower in patients given erector spinae plane block group within 48 h (relative risk 0.27, 95% CI 0.07 to 0.96, P = 0.037). There were no statistical differences in pain intensity at any timepoints between groups. No procedure-related adverse events occurred. CONCLUSIONS: Compared with wound infiltration, bilateral ultrasound-guided erector spinae plane block decreases short-term opioid consumption while providing similar analgesia in patients following lumbar spinal fusion surgery. Chinese Clinical Trial Registry: ChiCTR2100053008.


Assuntos
Bloqueio Nervoso , Fusão Vertebral , Humanos , Analgésicos Opioides/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Sufentanil/uso terapêutico , Bloqueio Nervoso/efeitos adversos , Analgesia Controlada pelo Paciente , Ultrassonografia de Intervenção
9.
Ren Fail ; 45(2): 2284842, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37994455

RESUMO

The multiple etiological characteristics of acute kidney injury (AKI) have brought great challenges to its clinical diagnosis and treatment. Renal injury in critically ill patients always indicates hemodynamic injury. The Critical Care UltraSound Guided (CCUSG)-A(KI)BCDE protocol developed by the Chinese Critical Ultrasound Study Group (CCUSG), respectively, includes A(KI) diagnosis and risk assessment and uses B-mode ultrasound, Color doppler ultrasound, spectral Doppler ultrasound, and contrast Enhanced ultrasound to obtain the hemodynamic characteristics of the kidney so that the pathophysiological mechanism of the occurrence and progression of AKI can be captured and the prognosis of AKI can be predicted combined with other clinical information; therefore, the corresponding intervention and treatment strategies can be formulated to achieve targeted, protocolized, and individualized therapy.


Assuntos
Injúria Renal Aguda , Rim , Humanos , Rim/diagnóstico por imagem , Injúria Renal Aguda/diagnóstico por imagem , Injúria Renal Aguda/etiologia , Cuidados Críticos , Hemodinâmica , Estado Terminal , Ultrassonografia de Intervenção/efeitos adversos
10.
BMC Psychiatry ; 22(1): 835, 2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-36581819

RESUMO

BACKGROUND: Subclinical anxiety, depressive and somatic symptoms appear closely related. However, it remains unclear whether somatic symptoms mediate the association between subclinical anxiety and depressive symptoms and what the underlying neuroimaging mechanisms are for the mediating effect. METHODS: Data of healthy participants (n = 466) and participants in remission of major depressive disorder (n = 53) were obtained from the Human Connectome Project. The Achenbach Adult Self-Report was adopted to assess anxiety, depressive and somatic symptoms. All participants completed four runs of resting-state functional magnetic resonance imaging. Mediation analyses were utilized to explore the interactions among these symptoms and their neuroimaging mechanisms. RESULTS: Somatic symptoms partially mediated the association between subclinical anxiety and depressive symptoms in healthy participants (anxiety→somatic→depression: effect: 0.2785, Boot 95% CI: 0.0958-0.3729; depression→somatic→anxiety: effect: 0.0753, Boot 95% CI: 0.0232-0.1314) and participants in remission of MDD (anxiety→somatic→depression: effect: 0.2948, Boot 95% CI: 0.0357-0.7382; depression→somatic→anxiety: effect: 0.0984, Boot 95% CI: 0.0007-0.2438). Resting-state functional connectivity (FC) between the right medial superior frontal gyrus and the left thalamus and somatic symptoms as chain mediators partially mediated the effect of subclinical depressive symptoms on subclinical anxiety symptoms in healthy participants (effect: 0.0020, Boot 95% CI: 0.0003-0.0043). The mean strength of common FCs of subclinical depressive and somatic symptoms, somatic symptoms, and the mean strength of common FCs of subclinical anxiety and somatic symptoms as chain mediators partially mediated the effect of subclinical depressive symptoms on subclinical anxiety symptoms in remission of MDD (effect: 0.0437, Boot 95% CI: 0.0024-0.1190). These common FCs mainly involved the insula, precentral gyri, postcentral gyri and cingulate gyri. Furthermore, FC between the triangular part of the left inferior frontal gyrus and the left postcentral gyrus was positively associated with subclinical anxiety, depressive and somatic symptoms in remission of MDD (FDR-corrected p < 0.01). CONCLUSIONS: Somatic symptoms partially mediate the interaction between subclinical anxiety and depressive symptoms. FCs involving the right medial superior frontal gyrus, left thalamus, triangular part of left inferior frontal gyrus, bilateral insula, precentral gyri, postcentral gyri and cingulate gyri maybe underlie the mediating effect of somatic symptoms.


Assuntos
Conectoma , Transtorno Depressivo Maior , Sintomas Inexplicáveis , Adulto , Humanos , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/diagnóstico por imagem , Depressão/complicações , Depressão/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Ansiedade/complicações , Ansiedade/diagnóstico por imagem , Encéfalo/diagnóstico por imagem
11.
Angew Chem Int Ed Engl ; 61(41): e202208667, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35876718

RESUMO

Single-atom sites (SASs) are commonly stabilized and influenced by neighboring atoms in the host; disclosing the structure-reactivity relationships of SASs in water electrolysis is one of the grand challenges originating from the tremendous wealth of support materials with complex structures. Through a multidisciplinary view of the design principles, synthesis strategies, characterization techniques, and theoretical analysis of structure-performance correlations, this timely Review is dedicated to summarizing the most recent progress in tailoring bond microenvironments on different supports and discussing the reaction pathways and performance advantages of different SAS structures for water electrolysis. The essence and mechanisms of how SAS structures influence electrocatalysis and the critical requirements for future developments are discussed. Finally, the challenges and perspectives are also provided to stimulate the practical, widespread utilization of SAS catalysts in water-splitting electrolyzers.

12.
Bioconjug Chem ; 32(8): 1763-1772, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34260853

RESUMO

Targeted radionuclide therapy (TRT) provides new and safe opportunities for cancer treatment and management with high precision and efficiency. Here we have designed a novel semiconducting polymer nanoparticle (SPN)-based radiopharmaceutical (211At-MeATE-SPN-GIP) for TRT against glucose-dependent insulinotropic polypeptide receptor (GIPR)-positive cancers to further explore the applications of nanoengineered TRT. 211At-MeATE-SPN-GIP was engineered via nanoprecipitation, followed by its functionalization with a glucose-dependent insulinotropic polypeptide (GIP) to target GIPR and deliver 211At for α therapy. The therapeutic effect and biological safety of 211At-MeATE-SPN-GIP were investigated using GIPR-overexpressing human pancreatic cancer CFPAC-1 cells and CFPAC-1-bearing mice. In this work, 211At-MeATE-SPN-GIP was produced with a radiochemical yield of 43% and radiochemical purity of 98%, which exhibited a specifically high uptake in CFPAC-1 cells, inducing cell cycle arrest at the G2/M phase and extensive DNA damage. In the CFPAC-1-bearing tumor model, 211At-MeATE-SPN-GIP exhibited high therapeutic efficiency, with no obvious side effects. The GIPR-specific binding of 211At-MeATE-SPN-GIP combined with effective inhibition of tumor growth and fewer side effects compared to control suggests that 211At-MeATE-SPN-GIP TRT holds great potential as a novel nanoengineered TRT strategy for patients with GIPR-positive cancer.


Assuntos
Astato/química , Nanopartículas/química , Neoplasias/tratamento farmacológico , Neoplasias Pancreáticas/terapia , Polímeros/química , Receptores dos Hormônios Gastrointestinais/metabolismo , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Neoplasias/metabolismo , Neoplasias Experimentais , Ligação Proteica , Radioisótopos , Receptores dos Hormônios Gastrointestinais/genética , Ensaios Antitumorais Modelo de Xenoenxerto
13.
J Nanobiotechnology ; 19(1): 337, 2021 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-34689758

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a devastatingly malignant tumor with a high mortality. However, current strategies to treat PDAC generally have low efficacy and high side-effects, therefore, effective treatment against PDAC remains an urgent need. RESULTS: We report a semiconducting polymer nano-radiopharmaceutical with intrinsic photothermal capability and labeling with therapeutic radioisotope 177Lu (177Lu-SPN-GIP) for combined radio- and photothermal therapy of pancreatic tumor. 177Lu-SPN-GIP endowed good stability at physiological conditions, high cell uptake, and long retention time in tumor site. By virtue of combined radiotherapy (RT) and photothermal therapy (PTT), 177Lu-SPN-GIP exhibited enhanced therapeutic capability to kill cancer cells and xenograft tumor in living mice compared with RT or PTT alone. More importantly, 177Lu-SPN-GIP could suppress the growth of the tumor stem cells and reverse epithelial mesenchymal transition (EMT), which may greatly reduce the occurrence of metastasis. CONCLUSION: Such strategy we developed could improve therapeutic outcomes over traditional RT as it is able to ablate tumor with relatively lower doses of radiopharmaceuticals to reduce its side effects.


Assuntos
Neoplasias Pancreáticas/metabolismo , Fototerapia/métodos , Pontos Quânticos , Compostos Radiofarmacêuticos , Animais , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Polímeros/química , Polímeros/farmacologia , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacologia , Nanomedicina Teranóstica , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Bioconjug Chem ; 31(2): 315-331, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-31765561

RESUMO

Inorganic nanoparticles as a versatile nanoplatform have been broadly applied in the diagnosis and treatment of cancers due to their inherent superior physicochemical properties (including magnetic, thermal, optical, and catalytic performance) and excellent functions (e.g., imaging, targeted delivery, and controlled release of drugs) through surface functional modification or ingredient dopant. However, in practical biological applications, inorganic nanomaterials are relatively difficult to degrade and excrete, which induces a long residence time in living organisms and thus may cause adverse effects, such as inflammation and tissue cysts. Therefore, the development of biodegradable inorganic nanomaterials is of great significance for their biomedical application. This Review will focus on the recent advances of degradable inorganic nanoparticles for cancer theranostics with highlight on the degradation mechanism, aiming to offer an in-depth understanding of degradation behavior and related biomedical applications. Finally, key challenges and guidelines will be discussed to explore biodegradable inorganic nanomaterials with minimized toxicity issues, facilitating their potential clinical translation in cancer diagnosis and treatment.


Assuntos
Nanopartículas/uso terapêutico , Neoplasias/diagnóstico , Neoplasias/terapia , Nanomedicina Teranóstica/métodos , Animais , Materiais Biocompatíveis/análise , Materiais Biocompatíveis/metabolismo , Materiais Biocompatíveis/uso terapêutico , Humanos , Compostos Inorgânicos/análise , Compostos Inorgânicos/metabolismo , Compostos Inorgânicos/uso terapêutico , Nanopartículas/análise , Nanopartículas/metabolismo , Nanopartículas/ultraestrutura
15.
J Cardiothorac Vasc Anesth ; 33(7): 1912-1918, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30442519

RESUMO

OBJECTIVE: Focused cardiac ultrasound (FCU) can provide useful information for the management of shock and acute respiratory distress syndrome. This study aimed to determine whether a 2-day focused cardiac ultrasound training course could enable critical care physicians to interpret ultrasound images in terms of left ventricular ejection fraction (LVEF), ratio of right ventricular end-diastolic area to left ventricular end-diastolic area (R/LVEDA), and septal kinetics. DESIGN: A prospective analysis of an image test score. SETTING: Ultrasound training programs in 7 regions across China. PARTICIPANTS: Two hundred forty-seven critical care physicians. INTERVENTIONS: All participants received a 2-day FCU training, including 4 sessions of basic heart function appraisal, 3 sessions of hands-on practice, and 1 session of image interpretation. MEASUREMENTS AND MAIN RESULTS: The post-training total scores were considerably higher than those of pretraining (75.6% v 58.9%, respectively, p < 0.001). After the course, the trainees obtained considerably higher scores on images with LVEF <30% than on images with LVEF 30% to 54% and LVEF ≥55% (100% v 60.0% and 60.0%, respectively, p < 0.001). The trainees obtained considerably higher scores on images with R/LVEDA >1 than on images with R/LVEDA 0.6 to 1 and R/LVEDA <0.6 (90.0% v 80.0% and 80.0%, p = 0.042 and p < 0.001, respectively). The trainees obtained considerably higher scores on images with paradoxical septal movement (PSM) than on images without PSM (100% v 75.0%, respectively, p < 0.001). CONCLUSION: The physicians' abilities to assess LVEF, RV enlargement, and PSM improved after the training course, and they demonstrated more accurate estimations of the most obviously abnormal images.


Assuntos
Competência Clínica , Ecocardiografia , Septos Cardíacos/fisiologia , Hipertrofia Ventricular Direita/diagnóstico , Médicos , Volume Sistólico , Função Ventricular Esquerda , Adulto , Cuidados Críticos , Feminino , Humanos , Masculino , Estudos Prospectivos
16.
Sensors (Basel) ; 19(7)2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30974747

RESUMO

A problem of tracking surface shape-shifting extended target by using gray scale pixels on optical image is considered. The measurement with amplitude information (AI) is available to the proposed method. The target is regarded as a convex hemispheric object, and the amplitude distribution of the extended target is represented by a solid radial function. The Gaussian process (GP) is applied and the covariance function of GP is modified to fit the convex hemispheric shape. The points to be estimated on the target surface are selected reasonably in the hemispheric space at the azimuth and pitch directions. Analytical representation of the estimated target extent is provided and the recursive process is implemented by the extended Kalman filter (EKF). In order to demonstrate the algorithm's ability of tracking complex shaped targets, a trailing target characterized by two feature parameters is simulated and the two feature parameters are extracted with the estimated points. The simulations verify the validity of the proposed method with compared to classical algorithms.

17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(4): 512-516, 2019 Aug 30.
Artigo em Zh | MEDLINE | ID: mdl-31484614

RESUMO

To study the clinicopathologic characteristics,immunohistochemical features,differential diagnosis,and prognosis of solitary fibrous tumours(SFT)/hemangiopericytomas(HPC)in the maters(meninx). Methods A series of 7 cases previously diagnosed as SFT/HPC at the Department of Pathology,Peking Union Medical College Hospital,during the period from 2008 to 2018 were analyzed for clinical data,histopathology,and immunohistochemical findings.The patients were followed up and the relevant literatures were reviewed. Results These seven patients included two males and 5 females aged 22 to 77 years(mean,49 years).Headache was the most common symptom.The magnetic resonance imaging of SFT/HPC showed irregularly contoured masses and dural tail sign was observed at the periphery of the lesion in 4 cases.The major axis of the tumor ranged from 1.8 cm to 10 cm(mean,4 cm).The tumors were located in the mater in 6 cases and in the spinal meninx in 1 case.The tumors were surgically removed in all cases.Under light microscope,the tumors were formed by long round,oval or spindle cells,with rich branching vascular pattern and varying quantity of collagenous fibers bands in both sparse areas and dense areas.According the WHO classification,2 cases were in WHO grade Ⅰ,2 cases in WHO grade Ⅱ,and 3 cases in WHO grade Ⅲ.Immunohistochemistry of the paraffin-embedded tissues in all cases showed positive immunoreativity for CD34 and vimentin in all seven cases,along with positive signal transducer and activator of transcription 6 in 4 cases,negative epithelial membrane antigen and S-100 in 7 cases,and negative progestational hormone and somatostatin receptor 2 in 6 cases.The Ki-67 index ranged from 1% to 15%.Five patients with follow-up data(including 1 current case)were alive,while 2 patients were lost to follow-up. Conclusions The SFT/HPC are rare in the maters(meninx)and is clinically difficult to be differentiated from other meningioma.The combination of CD34 and signal transducer and activator of transcription 6 helps to diagnose this disease.


Assuntos
Hemangiopericitoma/diagnóstico , Meninges/patologia , Tumores Fibrosos Solitários/diagnóstico , Adulto , Idoso , Antígenos CD34/metabolismo , Diagnóstico Diferencial , Feminino , Hemangiopericitoma/patologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Prognóstico , Fator de Transcrição STAT6/metabolismo , Tumores Fibrosos Solitários/patologia , Adulto Jovem
18.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(6): 815-820, 2019 Dec.
Artigo em Zh | MEDLINE | ID: mdl-31880111

RESUMO

OBJECTIVE: To explore the feasibility and effectiveness of gastric antrum cross-sectional area (CSA) mearsured by bedside ultrasound for predicting early feeding intolerance (FI) in critically ill patients. METHODS: The data were extracted from a multicenter prospective observation study between February 2018 to December 2018. A bivariate logistic regression model was established to identify the correlation between the gastric antrum cross-sectional area (CSA) and the feeding intolerance (FI). Draw the ROC curve to get the best cut-off value. RESULTS: This study comprises 150 patients. The mean age was (58.63±16.45) yr., the average APACHE Ⅱ score was 17.43±6.99. The incidence of FI for three days (72 h-FI%) was 28.0%. The multivariate analysis demonstrated that the Day 2 CSA-right lateral decubitus (RLD) was an independent risk factor for FI-day 2 (P=0.033), Day 3 CSA -RLD was an independent risk factor for FI-day 3 (P=0.016). Patients with day 3 CSA-RLD ≥7.092 cm2 had significantly higher rates of FI (P=0.001). CONCLUSION: Gastric antrum cross-sectional area measured by ultrasound can predict feeding intolerance during early enteral nutrition. When the Day 3 CSA-RLD is greater than 7.092 cm2, the incidence of feeding intolerance is significantly increased.


Assuntos
Estado Terminal , Antro Pilórico , Adulto , Idoso , Nutrição Enteral , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Ultrassonografia
19.
Angew Chem Int Ed Engl ; 58(32): 11088-11096, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31131511

RESUMO

Exogenous FeIII can be used for cancer magnetic resonance (MR) imaging and potentially for cancer treatment by a ferroptosis pathway or photothermal ablation. To achieve this, effective and accurate delivery of FeIII to cancerous sites is critical, requiring a balance of release kinetics of Fe3+ in tumorous and normal tissues. A nanoprobe is described consisting of upconversion luminescence (UCL) nanoparticles as a core and a coordinatively unsaturated FeIII -containing Fe3+ /gallic acid complex as a shell. Owing to the introduction of an unsaturated coordination structure, FeIII in the nanoprobe can be released only in the tumor microenvironment in response to the lightly acidic pH. The multiple UCLs are used for quantitatively visualizing the release of Fe3+ in vivo, whilst the release resultant serves as a photothermal agent. This nanoprobe exhibited ligand-free tumor targeting ability, activatable MR imaging performance, and efficacious therapeutic effects against tumors in vivo.


Assuntos
Antineoplásicos/farmacologia , Compostos Férricos/farmacologia , Corantes Fluorescentes/farmacologia , Imageamento por Ressonância Magnética , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Imagem Óptica , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Compostos Férricos/química , Corantes Fluorescentes/química , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas/química , Tamanho da Partícula , Propriedades de Superfície
20.
Crit Care Med ; 46(8): 1293-1301, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29771700

RESUMO

OBJECTIVES: We investigated whether preexisting kidney function determines if ICU patients may benefit from increased (2.0 g/kg/d) protein intake. DESIGN: Post hoc, hypothesis-generating, subgroup analysis of a multicenter, phase 2, randomized clinical trial. All analyses were conducted by intention to treat and maintained group allocation. Ninety-day mortality was the primary outcome. SETTING: ICUs of 16 hospitals throughout Australia and New Zealand. PATIENTS: Adult critically ill patients expected to remain in the study ICU for longer than 2 days. INTERVENTIONS: Random allocation to receive a daily supplement of up to 100 g of IV amino acids to achieve a total protein intake of 2.0 g/kg/d or standard nutrition care. MEASUREMENTS AND MAIN RESULTS: A total of 474 patients were randomized: 235 to standard care and 239 to IV amino acid supplementation. There was a statistically significant interaction between baseline kidney function and supplementation with study amino acids (p value for interaction = 0.026). Within the subgroup of patients with normal kidney function at randomization, patients who were allocated to receive the study amino acid supplement were less likely to die before study day 90 (covariate-adjusted risk difference, -7.9%; 95% CI, -15.1 to -0.7; p = 0.034). Furthermore, amino acid supplementation significantly increased estimated glomerular filtration rate in these patients (repeated-measures treatment × time interaction p = 0.009). Within the subgroup of patients with baseline kidney dysfunction and/or risk of progression of acute kidney injury, a significant effect of the study intervention on mortality was not found (covariate-adjusted risk difference, -0.6%; 95% CI, -16.2 to 15.2; p = 0.95). CONCLUSIONS: In this post hoc, hypothesis-generating, subgroup analysis, we observed reduced mortality and improved estimated glomerular filtration rate in ICU patients with normal kidney function who were randomly allocated to receive increased protein intake (up to 2.0 g/kg/d). We strongly recommend confirmation of these results in trials with low risk of bias before this treatment is recommended for routine care.


Assuntos
Injúria Renal Aguda/mortalidade , Injúria Renal Aguda/prevenção & controle , Aminoácidos/administração & dosagem , Estado Terminal/mortalidade , Unidades de Terapia Intensiva/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Aminoácidos/uso terapêutico , Austrália , Suplementos Nutricionais , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Nova Zelândia , Insuficiência Renal/tratamento farmacológico , Insuficiência Renal/mortalidade
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