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1.
Plant J ; 118(1): 90-105, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38113332

RESUMO

Necrotrophic fungal plant pathogens employ cell death-inducing proteins (CDIPs) to facilitate infection. However, the specific CDIPs and their mechanisms in pathogenic processes of Sclerotinia sclerotiorum, a necrotrophic pathogen that causes disease in many economically important crop species, have not yet been clearly defined. This study found that S. sclerotiorum secretes SsXyl2, a glycosyl hydrolase family 11 xylanase, at the late stage of hyphal infection. SsXyl2 targets the apoplast of host plants to induce cell death independent of xylanase activity. Targeted disruption of SsXyl2 leads to serious impairment of virulence, which can be recovered by a catalytically impaired SsXyl2 variant, thus supporting the critical role of cell death-inducing activity of SsXyl2 in establishing successful colonization of S. sclerotiorum. Remarkably, infection by S. sclerotiorum induces the accumulation of Nicotiana benthamiana hypersensitive-induced reaction protein 2 (NbHIR2). NbHIR2 interacts with SsXyl2 at the plasma membrane and promotes its localization to the cell membrane and cell death-inducing activity. Furthermore, gene-edited mutants of NbHIR2 displayed increased resistance to the wild-type strain of S. sclerotiorum, but not to the SsXyl2-deletion strain. Hence, SsXyl2 acts as a CDIP that manipulates host cell physiology by interacting with hypersensitive induced reaction protein to facilitate colonization by S. sclerotiorum. These findings provide valuable insights into the pathogenic mechanisms of CDIPs in necrotrophic pathogens and lead to a more promising approach for breeding resistant crops against S. sclerotiorum.


Assuntos
Ascomicetos , Melhoramento Vegetal , Plantas , Virulência , Nicotiana , Morte Celular , Doenças das Plantas/microbiologia
2.
Sensors (Basel) ; 24(15)2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39124072

RESUMO

Rotation modulation is a technique that relies on the specific rotation of an inertial measurement unit (IMU) to achieve the self-compensation of device errors. Common rotation schemes are classified into two modes: continuous rotation and a rotation-stop combination. Aiming at the problem of the poor modulation of slow-varying errors in the rotation-stop combination mode, a detailed analysis is conducted on the modulation effects of slow-varying errors in three schemes employing different rotation modes. Firstly, a detailed mathematical analysis is performed on the influence of gyro slow-varying drifts on two rotation modes, and the analysis results are validated through simulations. Subsequently, simulation experiments are conducted on three schemes to analyze their modulation effects on the slow-varying errors of inertial devices. The simulation results reveal that the modified dual-axis rotation scheme exhibits superior modulation effects on the slow-varying errors of inertial devices compared to the dual-axis sixteen-position rotation scheme and the multi-axis alternating continuous rotation scheme.

3.
Sensors (Basel) ; 24(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38931505

RESUMO

In order to reduce the position errors of the Global Positioning System/Strapdown Inertial Navigation System (GPS/SINS) integrated navigation system during GPS denial, this paper proposes a method based on the Particle Swarm Optimization-Back Propagation Neural Network (PSO-BPNN) to replace the GPS for positioning. The model relates the position information, velocity information, attitude information output by the SINS, and the navigation time to the position errors between the position information output by the SINS and the actual position information. The performance of the model is compared with the BPNN through an actual ship experiment. The results show that the PSO-BPNN can obviously reduce the position errors in the case of GPS signal denial.

4.
Environ Geochem Health ; 46(10): 383, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39167286

RESUMO

Traditional cement solidifying or stabilizing heavy metal-contaminated sites often face issues like alkalinity loss, cracking, and poor long-term performance. Therefore, bentonite-supported nano-zero-valent iron (B-nZVI) was introduced to optimize the remediation effect of cement in this paper. The effects of B-nZVI, ordinary Portland cement (OPC), and B-nZVI + OPC on the chemical stability of heavy metals and the physical strength of lead-contaminated soil were compared using semi-dynamic leaching methods, BCR tests, unconfined strength analysis, and micro-assisted analysis. Results demonstrated that the addition of B-nZVI effectively enhanced the remediation efficacy of OPC on lead-contaminated soil. The combination of B-nZVI and OPC exhibited a synergistic repair effect, offering superior physical strength and chemical stability for lead remediation. B-nZVI facilitated the adsorption and enrichment of Pb2+, thereby reducing oxidizable lead and enhancing short-term stabilization. Meanwhile, OPC precipitation and silicate gelling stabilized exchangeable lead into the residual form, necessitating repeated hydration gelling. Additionally, B-nZVI's sealing effect via water absorption delayed the leaching of exchangeable lead, thereby reducing lead migration. Even with only 1% B-nZVI added to the 12% OPC base, the leaching amount of Pb2+ decreased significantly from 67.6 to 6.59 mg/kg after 7 d of curing. The unconfined strength of contaminated soil treated with the composite solidifying agent for 7 d was 12.87% higher than that of OPC alone, and for 28 d, it was 36.48% higher. This optimization scheme presents a promising approach for effective and sustainable remediation of heavy metal-contaminated sites.


Assuntos
Materiais de Construção , Recuperação e Remediação Ambiental , Ferro , Chumbo , Poluentes do Solo , Poluentes do Solo/química , Chumbo/química , Recuperação e Remediação Ambiental/métodos , Ferro/química , Bentonita/química , Metais Pesados/química , Adsorção
5.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(2): 328-334, 2024 Apr 25.
Artigo em Zh | MEDLINE | ID: mdl-38686414

RESUMO

Superficial cartilage defect is an important factor that causes osteoarthritis. Therefore, it is very important to investigate the influence of superficial cartilage defects on its surface morphology and mechanical properties. In this study, the knee joint cartilage samples of adult pig were prepared, which were treated by enzymolysis with chymotrypsin and physical removal with electric friction pen, respectively. Normal cartilage and surface treated cartilage were divided into five groups: control group (normal cartilage group), chymotrypsin immersion group, chymotrypsin wiping group, removal 10% group with electric friction pen, and removal 20% group with electric friction pen. The surface morphology and structure of five groups of samples were characterized by laser spectrum confocal microscopy and environmental field scanning electron microscopy, and the mechanical properties of each group of samples were evaluated by tensile tests. The results show that the surface arithmetic mean height and fracture strength of the control group were the smallest, and the fracture strain was the largest. The surface arithmetic mean height and fracture strength of the removal 20% group with electric friction pen were the largest, and the fracture strain was the smallest. The surface arithmetic mean height, fracture strength and fracture strain values of the other three groups were all between the above two groups, but the surface arithmetic mean height and fracture strength of the removal 10% group with electric friction pen, the chymotrypsin wiping group and the chymotrypsin soaking group decreased successively, and the fracture strain increased successively. In addition, we carried out a study on the elastic modulus of different groups, and the results showed that the elastic modulus of the control group was the smallest, and the elastic modulus of the removal 20% group with electric friction pen was the largest. The above study revealed that the defect of the superficial area of cartilage changed its surface morphology and structure, and reduced its mechanical properties. The research results are of great significance for the prevention and repair of cartilage injury.


Assuntos
Cartilagem Articular , Animais , Suínos , Cartilagem Articular/fisiologia , Propriedades de Superfície , Fenômenos Biomecânicos , Articulação do Joelho/fisiologia , Estresse Mecânico , Resistência à Tração , Quimotripsina/metabolismo , Microscopia Eletrônica de Varredura
6.
Angew Chem Int Ed Engl ; 62(1): e202215594, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36342503

RESUMO

The effect of proton transfer on water oxidation has hardly been measurably established in heterogeneous electrocatalysts. Herein, two isomorphous manganese phosphates (NH4 MnPO4 ⋅ H2 O and KMnPO4 ⋅ H2 O) were designed to form an ideal platform to study the effect of proton transfer on water oxidation. The hydrogen-bonding network in NH4 MnPO4 ⋅ H2 O has been proven to be solely responsible for its better activity. The differences of the proton transfer kinetics in the two materials indicate a fast proton hopping transfer process with a low activation energy in NH4 MnPO4 ⋅ H2 O. In addition, the hydrogen-bonding network can effectively promote the proton transfer between adjacent Mn sites and further stabilize the MnIII -OH intermediates. The faster proton transfer results in a higher proportion of zeroth-order in [H+ ] for OER. Thus, proton transfer-affected electrocatalytic water oxidation has been measurably observed to bring detailed insights into the mechanism of water oxidation.

7.
Angew Chem Int Ed Engl ; 61(24): e202201104, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35355376

RESUMO

Integrating molecular catalysts into designed frameworks often enables improved catalysis. Compared with porphyrin-based frameworks, metal-corrole-based frameworks have been rarely developed, although monomeric metal corroles are usually more efficient than porphyrin counterparts for the electrocatalytic oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). We herein report on metal-corrole-based porous organic polymers (POPs) as ORR and OER electrocatalysts. M-POPs (M=Mn, Fe, Co, Cu) were synthesized by coupling metal 10-phenyl-5,15-(4-iodophenyl)corrole with tetrakis(4-ethynylphenyl)methane. Compared with metal corrole monomers, M-POPs displayed significantly enhanced catalytic activity and stability. Co-POP outperformed other M-POPs by achieving four-electron ORR with a half-wave potential of 0.87 V vs. RHE and reaching 10 mA cm-2 OER current density at 340 mV overpotential. This work is unparalleled to develop and explore metal-corrole-based POPs as electrocatalysts.

8.
Inf Process Manag ; 58(5): 102610, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36567974

RESUMO

During the outbreak of the new Coronavirus (2019-nCoV) in 2020, the spread of fake news has caused serious social panic. Fake news often uses multimedia information such as text and image to mislead readers, spreading and expanding its influence. One of the most important problems in fake news detection based on multimodal data is to extract the general features as well as to fuse the intrinsic characteristics of the fake news, such as mismatch of image and text and image tampering. This paper proposes a Multimodal Consistency Neural Network (MCNN) that considers the consistency of multimodal data and captures the overall characteristics of social media information. Our method consists of five subnetworks: the text feature extraction module, the visual semantic feature extraction module, the visual tampering feature extraction module, the similarity measurement module, and the multimodal fusion module. The text feature extraction module and the visual semantic feature extraction module are responsible for extracting the semantic features of text and vision and mapping them to the same space for a common representation of cross-modal features. The visual tampering feature extraction module is responsible for extracting visual physical and tamper features. The similarity measurement module can directly measure the similarity of multimodal data for the problem of mismatching of image and text. We assess the constructed method in terms of four datasets commonly used for fake news detection. The accuracy of the detection is improved clearly compared to the best available methods.

9.
Am J Transplant ; 20(4): 967-976, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31710417

RESUMO

Ex vivo lung perfusion (EVLP) with pharmacological reconditioning may increase donor lung utilization for transplantation (LTx). 3-Aminobenzamide (3-AB), an inhibitor of poly(ADP-ribose) polymerase (PARP), reduces ex vivo lung injury in rat lungs damaged by warm ischemia (WI). Here we determined the effects of 3-AB reconditioning on graft outcome after LTx. Three groups of donor lungs were studied: Control (Ctrl): 1 hour WI + 3 hours cold ischemia (CI) + LTx; EVLP: 1 hour WI + 3 hours EVLP + LTx; EVLP + 3-AB: 1 hour WI + 3 hours EVLP + 3-AB (1 mg. mL-1 ) + LTx. Two hours after LTx, we determined lung graft compliance, edema, histology, neutrophil counts in bronchoalveolar lavage (BAL), mRNA levels of adhesion molecules within the graft, as well as concentrations of interleukin-6 and 10 (IL-6, IL-10) in BAL and plasma. 3-AB reconditioning during EVLP improved compliance and reduced lung edema, neutrophil infiltration, and the expression of adhesion molecules within the transplanted lungs. 3-AB also attenuated the IL-6/IL-10 ratio in BAL and plasma, supporting an improved balance between pro- and anti-inflammatory mediators. Thus, 3-AB reconditioning during EVLP of rat lung grafts damaged by WI markedly reduces inflammation, edema, and physiological deterioration after LTx, supporting the use of PARP inhibitors for the rehabilitation of damaged lungs during EVLP.


Assuntos
Circulação Extracorpórea , Transplante de Pulmão , Animais , Benzamidas , Pulmão , Transplante de Pulmão/efeitos adversos , Perfusão , Ratos
10.
Heart Surg Forum ; 23(1): E053-E057, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32118543

RESUMO

BACKGROUND: The modified Blalock-Taussig shunt (MBTS) is used to palliate patients with restrictive pulmonary blood flow in complex cardiac anomalies. We describe the immediate and follow-up results of patients with MBTS in our center. METHODS: Patients who received MBTS (excluding those with hypoplastic left heart syndrome) from May 2008 to December 2018 were retrospectively identified. Hospital records were evaluated to determine patient demographics, diagnoses, and perioperative data. Patients were followed up by echocardiograph to evaluate the patency of the graft until stage II procedure or death. RESULTS: MBTS was performed in 25 patients by 2 surgeons; 16% were neonates, and 60% had pulmonary atresia and 24% tetralogy of Fallot. The patients' median age was 2.6 months (range 0.2 to 372), and median weight was 5.3 kg (range 1.9 to 45). Preoperative oxygen saturation (SaO2) was 68.7% ± 7.8%. Forty-eight percent of patients received a 3.5-mm graft, and 20% received a concomitant pulmonary arterioplasty with cardiopulmonary bypass. Postoperative SaO2 was 83.2% ± 3.6%, significantly different from preoperative SaO2 (P < .05). Follow-up duration was 1.2 years (range 0.3 to 7.8), with no graft blockage. Three patients died in hospital from cardiorespiratory decompensation after MBTS with concomitant pulmonary arterioplasty. The median age of patients receiving a stage II procedure was 1 year (range 0.4 to 17.4). Actuarial 1-year survival was 79.7% (95% confidence interval 53.1% to 92.2%). CONCLUSION: MBTS continues to be valuable for palliation of complicated cyanotic congenital heart disease, yet mortality was considerable with concomitant pulmonary arterioplasty. With effective coagulation, the patency rate of grafts was high.


Assuntos
Procedimento de Blalock-Taussig/métodos , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/cirurgia , Circulação Pulmonar , Adolescente , Adulto , Procedimento de Blalock-Taussig/efeitos adversos , Procedimentos Cirúrgicos Cardíacos , Criança , Pré-Escolar , Ecocardiografia , Feminino , Cardiopatias Congênitas/diagnóstico por imagem , Humanos , Lactente , Masculino , Oxigênio/sangue , Cuidados Paliativos , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
11.
Plant Dis ; 104(4): 1201-1206, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32065567

RESUMO

Sclerotinia sclerotiorum is one of the most devastating fungal plant pathogens of oilseed Brassica and is distributed worldwide. In particular, Sclerotinia stem rot has always been a serious threat to rapeseed production in Chongqing City, China. In this study, simple sequence repeat (SSR) markers and mycelial compatibility groups (MCGs) were used to characterize the population structure of 90 geographic isolates of S. sclerotiorum collected from rapeseed in nine counties of Chongqing. A total of 52 microsatellite haplotypes were identified, and a few haplotypes were found with high frequency. Gene diversity ranged from 0.1570 to 0.4700 in nine populations. A constructed unweighted pair group with arithmetic mean dendrogram based on Nei genetic distance and a STRUCTURE analysis revealed that the genetic composition of the isolates collected in the five counties located in western Chongqing are different from those collected in the two eastern counties, suggesting that breed lines should be cultivated in both the western and eastern regions to effectively evaluate resistance levels. A total of 47 MCGs were identified, and 72% of the MCGs was represented by single isolates. Seven of 13 MCGs that included at least two isolates contained isolates from only one county. SSR haplotypes were not correlated with MCGs. A subset of 34 isolates were inoculated on rapeseed stems, and the aggressiveness showed variation. This research revealed the population genetic structure and aggressiveness of this pathogen in Chongqing, and the results will help to develop disease management and resistance screening strategies.


Assuntos
Ascomicetos , Brassica napus , Brassica rapa , China , Doenças das Plantas
12.
BMC Surg ; 20(1): 17, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31952492

RESUMO

BACKGROUND: Iatrogenic aortic stenosis is a serious complication and potentially fatal due to erosion of the aortic wall. Timely management is necessary to prevent complications. CASE PRESENTATION: A 2-year-old boy underwent surgery to remove part of an Amplatzer occluder after patent ductus arteriosus (PDA) device embolization in the thoracic aorta. He exhibited moderate to severe obstruction with erosion of the intimal layer of the aorta caused by the device, part of which was retrieved surgically with restructuring of the thoracic aorta segment and occluder remnant. The patient's postoperative course was uneventful. CONCLUSIONS: When possible, retrieving only part of an embolized device can be advocated because it reduces the risk of aortic and pulmonary artery damage.


Assuntos
Coartação Aórtica/cirurgia , Permeabilidade do Canal Arterial/cirurgia , Dispositivo para Oclusão Septal , Aorta/cirurgia , Aorta Torácica/cirurgia , Pré-Escolar , Remoção de Dispositivo , Humanos , Doença Iatrogênica , Masculino
13.
Bull Environ Contam Toxicol ; 105(2): 237-243, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32651610

RESUMO

We assessed the effects of carbon dioxide (CO2) and decabromodiphenyl ether (BDE-209, 0, 3 and 30 mg/kg) on rice (Oryza sativa L. cv. Wuyunjing) in field free-air CO2 enrichment system. Rice at elevated (580 ppm) CO2 had increased net photosynthetic rate, intercellular CO2 concentration, shoot biomass, yield and phosphorus content in grains. However, there were no significant changes in such parameters observed on rice at elevated CO2 combined with BDE-209 (3 and 30 mg/kg). Elevated CO2 alone had no significant effects on sugar or starch content in rice grains, whereas its combination with BDE-209 (3 mg/kg) significantly decreased grain sugar and starch content. In conclusion, rice reared in soil polluted by BDE-209 under elevated CO2 modulates the effects in grain feature.


Assuntos
Dióxido de Carbono/toxicidade , Éteres Difenil Halogenados/toxicidade , Oryza/efeitos dos fármacos , Poluentes do Solo/toxicidade , Biomassa , Dióxido de Carbono/análise , China , Mudança Climática , Grão Comestível/química , Grão Comestível/efeitos dos fármacos , Éteres Difenil Halogenados/análise , Oryza/química , Fotossíntese/efeitos dos fármacos , Solo/química , Poluentes do Solo/análise
14.
Am J Emerg Med ; 37(7): 1346-1352, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31029521

RESUMO

BACKGROUND: We aimed to analyse the association between high-level growth-differentiation factor-15 (GDF-15) and mortality, recurrent MI and heart failure compared to low-level GDF-15 in patients with acute coronary syndrome (ACS). METHODS: PubMed and EMBASE were searched from their commencement to December 2017 for qualified studies that evaluated the associations between GDF-15 and ACS. Risk ratios were synthesized with random effect meta-analysis. Publication bias and sensitivity analyses were also conducted. RESULTS: A total of thirteen studies and 43,547 participants were analyzed systematically in our meta-analysis. Our study showed a significant association between GDF-15 values and mortality (p = 0.000, RR = 6.75, 95% CI = 5.81-7.84) and recurrent MI (p = 0.000, RR = 1.95, 95% CI = 1.72-2.21) in the overall analyses. Subgroup analyses revealed similar results. However, there was evidence of heterogeneity in the study of heart failure, whose overall RR was 6.66, with an I2 of 87.3%. CONCLUSION: There was a significant association between high-level GDF-15 and mortality, recurrent MI in patients with ACS. We need more data to research the risk stratification of heart failure in ACS patients in the future.


Assuntos
Síndrome Coronariana Aguda/sangue , Fator 15 de Diferenciação de Crescimento/sangue , Insuficiência Cardíaca/sangue , Infarto do Miocárdio/sangue , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/mortalidade , Biomarcadores/sangue , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/mortalidade , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Recidiva
15.
J Therm Biol ; 84: 323-330, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31466770

RESUMO

Local heat can accelerate the blood circulation and induce the vasodilatation. Investigators reported that local heat causes an increase in skin blood flow consisting of two phases. The first is solely sensory neural, and the second is nitric oxide mediated. However, the mechanism underlying the skin blood flow response to local heating are complex and poorly understood. The mechanisms behind these two phases are deduced to be linked by flow-mediated dilation. In this study, the variation of the blood flow and the blood vessel diameter are monitored during local heating. According to the dynamic blood flow, the theoretical model of flow mediated dilation involving the key agents production and transportation was first used to study vasodilatation process during heating, and the variations of blood vessel was obtained. Finally, accurate distributions of the nitric oxide, calcium and myosin concentrations in the arterial wall were found during autoregulation. We evaluated the time course of the blood vessel changing and verified the fact that the second increase in blood flow is the result of flow dilation mediation. The effects of dilation of blood vessel were also analyzed.


Assuntos
Temperatura Alta , Modelos Biológicos , Fenômenos Fisiológicos da Pele , Pele/irrigação sanguínea , Vasodilatação , Animais , Vasos Sanguíneos/fisiologia , Simulação por Computador , Camundongos , Camundongos Nus , Fluxo Sanguíneo Regional
16.
Inorg Chem ; 57(17): 10511-10517, 2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-30118221

RESUMO

Unexpected Sc/Ln codoped rare earth metal-organic frameworks (RE-MOFs) molecular alloys (MAs) based on an oxalic acid ligands were obtained. Calcination of the RE-MOFs MAs gave the corresponding codoped rare earth oxides a strong and nearly pure red color upconversion luminescence. It allows the resulting lanthanide ion (Ln3+) doped upconversion materials a wide range of applications from optical communications to disease diagnosis. Moreover, the pyrolysis RE-MOFs MAs precursor has demonstrated to be an effective preparation method for a uniform Ln-doped Sc2O3 system.

17.
Cryobiology ; 81: 81-87, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29448018

RESUMO

Intracellular ice formation (IIF) is the major cause of death in cells subjected to freezing. The occurrence of intracellular ice prevents the penetration of light into the camera and makes the image dark. Therefore, the gray-level variation can reflect the IIF. However, cell deformation is accompanied with IIF, especially for larger cells. It is necessary to account this entire phenomenon together in a single method. In this paper, the normalized parameter C defined by the gray-level variation depending on the displacement was defined to reflect the gray-level change of each pixel point in the region of interest of the image. The process of IIF of onion epidermal cells and 293T cells was analyzed by this method.


Assuntos
Microscopia Crioeletrônica/métodos , Criopreservação/métodos , Células Epiteliais/ultraestrutura , Congelamento , Processamento de Imagem Assistida por Computador/métodos , Células HEK293 , Humanos , Gelo , Cebolas , Gravação em Vídeo
19.
Lasers Surg Med ; 47(4): 323-30, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25639847

RESUMO

BACKGROUND: The pre-conditioning of tumor vessels by low-dose photodynamic therapy (L-PDT) was shown to enhance the distribution of chemotherapy in different tumor types. However, how light dose affects drug distribution and tumor response is unknown. Here we determined the effect of L-PDT fluence on vascular transport in human mesothelioma xenografts. The best L-PDT conditions regarding drug transport were then combined with Lipoplatin(®) to determine tumor response. METHODS: Nude mice bearing dorsal skinfold chambers were implanted with H-Meso1 cells. Tumors were treated by Visudyne(®) -mediated photodynamic therapy with 100 mW/cm(2) fluence rate and a variable fluence (5, 10, 30, and 50 J/cm(2) ). FITC-Dextran (FITC-D) distribution was assessed in real time in tumor and normal tissues. Tumor response was then determined with best L-PDT conditions combined to Lipoplatin(®) and compared to controls in luciferase expressing H-Meso1 tumors by size and whole body bioluminescence assessment (n = 7/group). RESULTS: Tumor uptake of FITC-D following L-PDT was significantly enhanced by 10-fold in the 10 J/cm(2) but not in the 5, 30, and 50 J/cm(2) groups compared to controls. Normal surrounding tissue uptake of FITC-D following L-PDT was significantly enhanced in the 30 J/cm(2) and 50 J/cm(2) groups compared to controls. Altogether, the FITC-D tumor to normal tissue ratio was significantly higher in the 10 J/cm(2) group compared others. Tumor growth was significantly delayed in animals treated by 10 J/cm2-L-PDT combined to Lipoplatin(®) compared to controls. CONCLUSIONS: Fluence of L-PDT is critical for the optimal distribution and effect of subsequently administered chemotherapy. These findings have an importance for the clinical translation of the vascular L-PDT concept in the clinics.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Mesotelioma/terapia , Fotoquimioterapia , Animais , Linhagem Celular Tumoral , Dextranos/farmacocinética , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/farmacocinética , Corantes Fluorescentes/farmacocinética , Humanos , Mesotelioma/patologia , Camundongos Nus , Microscopia , Terapia Neoadjuvante , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Verteporfina , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Mediators Inflamm ; 2015: 412319, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25705092

RESUMO

Extracorporeal circulation (ECC) is necessary for conventional cardiac surgery and life support, but it often triggers systemic inflammation that can significantly damage tissue. Studies of ECC have been limited to large animals because of the complexity of the surgical procedures involved, which has hampered detailed understanding of ECC-induced injury. Here we describe a minimally invasive mouse model of ECC that may allow more extensive mechanistic studies. The right carotid artery and external jugular vein of anesthetized adult male C57BL/6 mice were cannulated to allow blood flow through a 1/32-inch external tube. All animals (n = 20) survived 30 min ECC and subsequent 60 min observation. Blood analysis after ECC showed significant increases in levels of tumor necrosis factor α, interleukin-6, and neutrophil elastase in plasma, lung, and renal tissues, as well as increases in plasma creatinine and cystatin C and decreases in the oxygenation index. Histopathology showed that ECC induced the expected lung inflammation, which included alveolar congestion, hemorrhage, neutrophil infiltration, and alveolar wall thickening; in renal tissue, ECC induced intracytoplasmic vacuolization, acute tubular necrosis, and epithelial swelling. Our results suggest that this novel, minimally invasive mouse model can recapitulate many of the clinical features of ECC-induced systemic inflammatory response and organ injury.


Assuntos
Circulação Extracorpórea , Animais , Creatinina/sangue , Cistatina C/sangue , Interleucina-6/metabolismo , Elastase de Leucócito/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Pneumonia/sangue , Pneumonia/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
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