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Developing ultrasensitive and user-friendly methods for the detection glucose has attracted more and more attention. By virtue of high selectivity and sensitivity, enzyme-based glucose sensor plays a key role in point-of-care sensing technology for detecting glucose concentration. In this study, Amplex Red (AR), as both indicator and mediator, was investigated to detect glucose in presence of glucose oxidase (GOx) enzymes using colorimetric and electrochemical methods. Without using any advanced techniques and sophisticated nanomaterials, 1 µM glucose can be easily detected through simply detecting the solution color with a visual colorimetric method. On the other hand, the electrochemical method can provide much higher sensitivity for the detection of glucose, which achieves a linear range spanning from 20 nM to 3.56 µM with a limit of 7.3 nM (signal-to-noise ratio SNR = 3). It is also found that the presence of other sugars such as fructose, lactose, and maltose have very limited interference effects on the detection of glucose. More importantly, a bare GC electrode was used in all these electrochemical measurements without any electrode surface modification, guaranteeing a simple and fast operation. The analytical platforms for the detection of glucose presented here not only provide simple, fast, and ultrasensitive methods, but also have the potential to advance the sensing technology in the application of other health diagnostic research areas. Amplex Red (AR) was reported as both an indicator and mediator for the sensitive and specific determination of glucose using the colorimetric and electrochemical methods. The detection limit was 1 µM glucose by the visual colorimetric methods. A bare glassy carbon electrode without any functional modification was employed for the detection as low as 20 nM glucose with LOD of 7.3 nm (SNR = 3) in the electrochemical method.
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Glicemia/análise , Colorimetria/métodos , Técnicas Eletroquímicas/métodos , Glucose Oxidase/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Limite de DetecçãoRESUMO
This study aimed to use micro-FTIR with transmission mode to investigate cellulose crystallinity of developing cotton fibers. Compared with ATR-FTIR method, we found that micro-FTIR can obtain more information of cellulose inside of the developing cotton fibers, especially in high wavenumber of 2800-3000 cm-1 region. Combined with curve fitting method, a new IR crystallinity index (CI) method named wax crystallinity index (WCI) was introduced to evaluate the cellulose crystallinity in the development of cotton fibers based on the peak and area ratios of 2900 cm-1/2850 cm-1 and 2900 cm-1/2920 cm-1. The obtained WCI values demonstrated an excellent coefficient of determination with X-ray diffraction (XRD) CI method with the value up to 0.99. This study suggested that micro-FTIR was an effective technique to qualitatively analyze the crystallinity in developing cotton fibers combined with curve fitting method.
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Celulose/análise , Fibra de Algodão/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Cristalização , Difração de Raios XRESUMO
Natural killer (NK) cells accumulate at the maternal-fetal interface in large numbers, but their exact roles in successful pregnancy remain poorly defined. Here, we provide evidence that T(H)17 cells and local inflammation can occur at the maternal-fetal interface during natural allogenic pregnancies. We found that decidual NK cells promote immune tolerance and successful pregnancy by dampening inflammatory T(H)17 cells via IFN-γ secreted by the CD56(bright)CD27(+) NK subset. This NK-cell-mediated regulatory response is lost in patients who experience recurrent spontaneous abortions, which results in a prominent T(H)17 response and extensive local inflammation. This local inflammatory response further affects the regulatory function of NK cells, leading to the eventual loss of maternal-fetal tolerance. Thus, our data identify NK cells as key regulatory cells at the maternal-fetal interface by suppressing T(H)17-mediated local inflammation.
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Tolerância Imunológica , Células Matadoras Naturais/imunologia , Troca Materno-Fetal/imunologia , Células Th17/imunologia , Aborto Habitual/etiologia , Aborto Habitual/imunologia , Aborto Habitual/patologia , Adulto , Animais , Antígeno CD56/metabolismo , Citocinas/biossíntese , Decídua/imunologia , Decídua/patologia , Feminino , Feto/imunologia , Humanos , Interferon gama/metabolismo , Isoantígenos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Endogâmicos DBA , Camundongos Transgênicos , Gravidez , Primeiro Trimestre da Gravidez/imunologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismoRESUMO
A computational fluid dynamics (CFD) methodology for simulating the combustion process has been validated with experimental results. Three different types of experimental setups were used to validate the CFD model. These setups include an industrial-scale flare setups and two lab-scale flames. The CFD study also involved three different fuels: C3H6/CH/Air/N2, C2H4/O2/Ar and CH4/Air. In the first setup, flare efficiency data from the Texas Commission on Environmental Quality (TCEQ) 2010 field tests were used to validate the CFD model. In the second setup, a McKenna burner with flat flames was simulated. Temperature and mass fractions of important species were compared with the experimental data. Finally, results of an experimental study done at Sandia National Laboratories to generate a lifted jet flame were used for the purpose of validation. The reduced 50 species mechanism, LU 1.1, the realizable k-epsilon turbulence model, and the EDC turbulence-chemistry interaction model were usedfor this work. Flare efficiency, axial profiles of temperature, and mass fractions of various intermediate species obtained in the simulation were compared with experimental data and a good agreement between the profiles was clearly observed. In particular the simulation match with the TCEQ 2010 flare tests has been significantly improved (within 5% of the data) compared to the results reported by Singh et al. in 2012. Validation of the speciated flat flame data supports the view that flares can be a primary source offormaldehyde emission.
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Simulação por Computador , Incêndios , Modelos Teóricos , Ar , Gases , Hidrodinâmica , Indústrias , TemperaturaRESUMO
Among the most frequently diagnosed cancers in developing countries, esophageal squamous cell carcinoma (ESCC) ranks among the top six causes of death. It would be beneficial if a rapid, accurate, and automatic ESCC diagnostic method could be developed to reduce the workload of pathologists and improve the effectiveness of cancer treatments. Using micro-FTIR spectroscopy, this study classified the transformation stages of ESCC tissues. Based on 6,352 raw micro-FTIR spectra, a one-dimensional convolutional neural network (1D-CNN) model was constructed to classify-five stages. Based on the established model, more than 93% accuracy was achieved at each stage, and the accuracy of identifying proliferation, low grade neoplasia, and ESCC cancer groups was achieved 99% for the test dataset. In this proof-of-concept study, the developed method can be applied to other diseases in order to promote the use of FTIR spectroscopy in cancer pathology.
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Carcinoma de Células Escamosas , Aprendizado Profundo , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/patologia , Espectroscopia de Infravermelho com Transformada de Fourier , Redes Neurais de ComputaçãoRESUMO
Quantifying the air-surface exchange of Hg(o) from soils is critical to understanding the cycling of mercury in different environmental compartments. Dynamic flux chambers (DFCs) have been widely employed for Hg(o) flux measurement over soils. However, DFCs of different sizes, shapes, and sampling flow rates yield distinct measured fluxes for a soil substrate under identical environmental conditions. In this study, we performed an integrated modeling, laboratory and field study to design a DFC capable of producing a steady and uniform air flow over a flat surface. The new DFC was fabricated using polycarbonate sheets. The internal velocity field was experimentally verified against model predictions using both theoretical and computational fluid dynamics techniques, suggesting fully developed flow with velocity profiles in excellent agreement with model results. Laboratory flux measurements demonstrated that the new design improves data reproducibility as compared to a conventional DFC, and reproduces the model-predicted flux trend with increasing sampling flow. A mathematical relationship between the sampling flow rate and surface friction velocity, a variable commonly parametrized in atmospheric models, was developed for field application. For the first time, the internal shear property of a DFC can be precisely controlled using the sampling flow rate, and the flux under atmospheric condition can be inferred from the measured flux and surface shear property. The demonstrated methodology potentially bridges the gap in measured fluxes obtained by the DFC method and the micrometeorological methods.
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Mercúrio/química , Poluentes do Solo/química , ArRESUMO
Fourier transform infrared (FTIR) spectroscopy, as a platform technology for cancer detection, must be up to the challenge of clinical transformation. To this end, detection of esophageal squamous cell carcinoma (ESCC) was hereby explored using serum and plasma scrape-coated on barium fluoride (BaF2) disk by transmission FTIR method, and the classification model was built using six multivariate statistical analyses, including support vector machine (SVM), principal component linear discriminant analysis (PC-LDA), decision tree (DT), k-nearest neighbor (KNN) classification, ensemble algorithms (EA) and partial least squares for discriminant analysis (PLS-DA). All statistical analyses methods demonstrated that late-stage cancer could be well classified from healthy people employing either serum or plasma with different anticoagulants. Resulting PC-LDA model differentiated late-stage cancer from normal group with an accuracy of 99.26%, a sensitivity of 98.53%, and a specificity of 100%. The accuracy and sensitivity reached 97.08% and 91.43%, respectively for early-stage cancer discrimination from normal group. This pilot exploration demonstrated that transmission FTIR provided a rapid, cost effective and sensitive method for ESCC diagnosis using either serum or plasma.
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Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Fotoquimioterapia , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Neoplasias Esofágicas/diagnóstico , Fármacos Fotossensibilizantes , Fotoquimioterapia/métodos , Carcinoma de Células Escamosas do Esôfago/diagnóstico , Análise Discriminante , Análise de Componente Principal , Análise dos Mínimos Quadrados , Máquina de Vetores de SuporteRESUMO
We herein report a novel, reliable and inexpensive method for detecting esophageal cancer using blood plasma resonance Raman spectroscopy combined with multivariate analysis methods. The blood plasma samples were divided into late stage cancer group (n = 164), early stage cancer group (n = 35) and normal group (n = 135) based on clinical pathological diagnosis. Using a specially designed quartz capillary tube as sample holder, we obtained higher quality resonance Raman spectra of blood plasma than existing method. The study demonstrated that the carotenoids levels in blood plasma were reduced in esophageal cancer patients. The area under the receiver operating characteristic curve (and 95% confidence interval) calculated by wavenumber selection and principal component analysis combined with linear discriminant analysis (PC-LDA) algorithm were 0.894 (0.858-0.929), 0.901 (0.841-0.960) and 0.871 (0.799-0.942) for differentiating late cancer from normal, late cancer from early cancer, and early cancer from normal respectively. The contribution from the two carotenoids wavenumber regions of 1155 and 1515 cm-1 were more than 84.2%. The results show that the plasma carotenoids could be a potential biomarker for screening esophageal cancer using resonance Raman spectroscopy combined with wavenumber selection and PC-LDA algorithms.
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Neoplasias Esofágicas , Análise Espectral Raman , Análise Discriminante , Neoplasias Esofágicas/diagnóstico , Humanos , Análise Multivariada , Plasma , Análise de Componente PrincipalRESUMO
Background Ischaemia-reperfusion injury is considered an inevitable component of organ transplantation, compromising organ quality and outcomes. Although several treatments have been proposed, none has avoided graft ischaemia and its detrimental consequences. Methods Ischaemia-free liver transplantation (IFLT) comprises surgical techniques enabling continuous oxygenated blood supply to the liver of brain-dead donor during procurement, preservation, and implantation using normothermic machine perfusion technology. In this non-randomised study, 38 donor livers were transplanted using IFLT and compared to 130 conventional liver transplants (CLT). Findings Two recipients (5â¢3%) in the IFLT group experienced early allograft dysfunction, compared to 50â¢0% in patients receiving conventional transplants (absolute risk difference, 44â¢8%; 95% confidence interval, 33â¢6-55â¢9%). Recipients of IFLT had significantly reduced median (IQR) peak aspartate aminotransferase levels within the first week compared to CLT recipients (365, 238-697 vs 1445, 791-3244 U/L, p<0â¢001); likewise, median total bilirubin levels on day 7 were significantly lower (2â¢34, 1â¢39-4â¢09 mg/dL) in the IFLT group than in the CLT group (5â¢10, 1â¢90-11â¢65 mg/dL) (p<0â¢001). Moreover, IFLT recipients had a shorter median intensive care unit stay (1â¢48, 0â¢75-2â¢00 vs 1â¢81, 1â¢00-4â¢58 days, p=0â¢006). Both one-month recipient (97â¢4% vs 90â¢8%, p=0â¢302) and graft survival (97.4% vs 90â¢0%, p=0â¢195) were better for IFLT than CLT, albeit differences were not statistically significant. Subgroup analysis showed that the extended criteria donor livers transplanted using the IFLT technique yielded faster post-transplant recovery than did the standard criteria donor livers transplanted using the conventional approach. Interpretation IFLT provides a novel approach that may improve outcomes, and allow the successful utilisation of extended criteria livers. Funding This study was funded by National Natural Science Foundation of China, Guangdong Provincial Key Laboratory Construction Projection on Organ Donation and Transplant Immunology, and Guangdong Provincial international Cooperation Base of Science and Technology. Panel: Research in context.
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This study aimed to determine whether mesenchymal stem cells (MSCs) derived from umbilical cord blood (UCB) would promote cutaneous wound healing. MSCs from human UCB were isolated and identified. The characteristics of the isolated MSCs' growth and proliferation were assayed in vitro. The MSCs labeled with 5-bromodeoxyuridine (BrdU) were applied on fresh cutaneous mice wounds. The healing rates were surveyed. The distribution and the differentiation into keratinocytes of the labeled MSCs in the wound tissue were checked by immunohistochemistry staining. The isolated MSCs could grow and proliferate well in vitro. The isolated MSCs from UCB could be labeled by 5-bromodeoxyuridine successfully. The MSCs derived from UCB could enhance the healing of mice skin defect wounds, and it was found that the implanted MSCs could differentiate into keratinocyte in the wound tissue. It was demonstrated that MSCs from UCB can be isolated and proliferated successfully. The local administration of MSCs derived from UCB improves skin defect wound healing in mice.
Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Transplante de Células-Tronco Mesenquimais/métodos , Pele/lesões , Cicatrização , Ferimentos e Lesões/cirurgia , Animais , Diferenciação Celular , Células Cultivadas , Modelos Animais de Doenças , Epiderme/patologia , Feminino , Citometria de Fluxo , Seguimentos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pele/patologia , Resultado do Tratamento , Ferimentos e Lesões/patologiaRESUMO
BACKGROUND AND AIMS: Liver injury induced by concanavalin A (Con A) is often used as a model to study the pathophysiology of immune mediated liver injury. Rapamycin (Rapa) is an effective immunosuppressant widely used for preventing immune activation and transplant rejection. However, the effect of Rapa on liver injury caused by Con A has not been carefully examined. In the present study, we examined the effect of Rapa on liver injury caused by Con A. METHODS: Mice received intraperitoneal Rapa injection before Con A intravenous administration. The liver injury was examined by measuring serum transaminase and pathology, and the level of cytokines was detected by enzyme linked immunosorbent assay (ELISA). RESULTS: In the present study, we examined the effect of Rapa on liver injury after Con A injection in mice. We found that the treatment of mice with Rapa protected the liver from Con A-induced injury. Pretreatment with Rapa dramatically ameliorated Con A-induced mortality. This protection was associated with reduced transaminase levels in the blood and further confirmed by liver histology. ELISA showed that Rapa suppressed pro-inflammatory cytokines IFN-gamma and TNF-alpha production as compared with the untreated controls. Furthermore, intrahepatic lymphocyte proliferation was significantly inhibited. CONCLUSION: These findings suggested that Rapa has the therapeutic potential for treatment of immune-mediated liver injury in the clinic.
Assuntos
Imunossupressores/farmacologia , Hepatopatias/prevenção & controle , Fígado/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Sirolimo/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas , Concanavalina A , Citoproteção , Modelos Animais de Doenças , Regulação para Baixo , Ensaio de Imunoadsorção Enzimática , Imunossupressores/administração & dosagem , Mediadores da Inflamação/sangue , Injeções Intraperitoneais , Interferon gama/sangue , Interleucina-4/sangue , Fígado/imunologia , Fígado/patologia , Hepatopatias/imunologia , Hepatopatias/patologia , Linfócitos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sirolimo/administração & dosagem , Fatores de Tempo , Transaminases/sangue , Fator de Necrose Tumoral alfa/sangueRESUMO
To evaluate the influence of transition metal substituents on the characteristics of CH3NH3PbI3/TiO2, we investigated the geometrical and electronic properties of transition metal-substituted CH3NH3PbI3/TiO2 by first-principles calculations. The results suggested that the substitution of Ti4+ at the five-fold coordinated (Ti5c) sites by transition metals is energetically favored. The substituted interface has enhanced visible light sensitivity and photoelectrocatalytic activity by reducing the transition energies. The transition metal substitution can effectively tune the band gap of the interface, which significantly improves the photo-reactivity. The substituted systems are expected to be more efficient in separating the photo-generated electrons-holes and active in the visible spectrum.
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Background: Ischemia-reperfusion injury (IRI) has been considered an inevitable event in organ transplantation since the first successful kidney transplant was performed in 1954. To avoid IRI, we have established a novel procedure called ischemia-free organ transplantation. Here, we describe the first case of ischemia-free kidney transplantation (IFKT). Materials and Methods: The kidney graft was donated by a 19-year-old brain-dead donor. The recipient was a 47-year-old man with end-stage diabetic nephropathy. The graft was procured, preserved, and implanted without cessation of blood supply using normothermic machine perfusion. Results: The graft appearance, perfusion flow, and urine production suggested that the kidney was functioning well-during the whole procedure. The creatinine dropped rapidly to normal range within 3 days post-transplantation. The levels of serum renal injury markers were low post-transplantation. No rejection or vascular or infectious complications occurred. The patient had an uneventful recovery. Conclusion: This paper marks the first case of IFKT in humans. This innovation may offer a unique solution to optimizing transplant outcomes in kidney transplantation.
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To evaluate the antibacterial effect of multivalent silver ion carried by zirconium phosphate (ZP-Ag) both in vitro and in an experimental rat burn wound compared with that of sulfadiazine silver (SD-Ag). Firstly, the minimal inhibition concentration and the minimal bactericidal concentration of ZP-Ag to three different strains of bacteria (Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli) were compared with those of SD-Ag in vitro. Following this dressings containing the same mass of ZP-Ag or SD-Ag were applied to wounds in a rat burn model and their antimicrobial activity assayed. The inflammatory response of the wounds managed with the two kinds of dressings was compared. Both the minimal inhibition concentration and minimal bactericidal concentration of ZP-Ag to S. aureus, P. aeruginosa, and E. coli were two to four times lower than those of SD-Ag. In vivo ZP-Ag had a more effective antibacterial action inhibiting the growth of the above three bacterial strains under burn scar, compared with dressings made from the same mass of SD-Ag. Moreover, the antibacterial effect was unchanged after the ZP-Ag dressings were washed 20 times, while it dramatically decreased after the dressings with SD-Ag were washed 20 times. When covered by either regular or washed ZP-Ag dressings, the wounds showed integrity with no visible inflammatory reaction. However, various extents of inflammatory reactions on or around the wounds covered with regular SD-Ag dressing were observed. This study showed that dressings with ZP-Ag had a prominent and relative long-term antibacterial effect. ZP-Ag dressings could be an effective, low-cost management option for burn wounds.
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Anti-Infecciosos Locais/administração & dosagem , Bandagens , Queimaduras/terapia , Sulfadiazina de Prata/administração & dosagem , Prata/administração & dosagem , Zircônio/administração & dosagem , Animais , Terapia Combinada , Modelos Animais de Doenças , Íons/administração & dosagem , Ratos , Ratos WistarRESUMO
Emissions from flares constitute unburned hydrocarbons, carbon monoxide (CO), soot, and other partially burned and altered hydrocarbons along with carbon dioxide (CO2) and water. Soot or visible smoke is of particular concern for flare operators/regulatory agencies. The goal of the study is to develop a computational fluid dynamics (CFD) model capable of predicting flare combustion efficiency (CE) and soot emission. Since detailed combustion mechanisms are too complicated for (CFD) application, a 50-species reduced mechanism, LU 3.0.1, was developed. LU 3.0.1 is capable of handling C4 hydrocarbons and soot precursor species (C2H2, C2H4, C6H6). The new reduced mechanism LU 3.0.1 was first validated against experimental performance indicators: laminar flame speed, adiabatic flame temperature, and ignition delay. Further, CFD simulations using LU 3.0.1 were run to predict soot emission and CE of air-assisted flare tests conducted in 2010 in Tulsa, Oklahoma, using ANSYS Fluent software. Results of non-premixed probability density function (PDF) model and eddy dissipation concept (EDC) model are discussed. It is also noteworthy that when used in conjunction with the EDC turbulence-chemistry model, LU 3.0.1 can reasonably predict volatile organic compound (VOC) emissions as well. IMPLICATIONS: A reduced combustion mechanism containing 50 C1-C4 species and soot precursors has been developed and validated against experimental data. The combustion mechanism is then employed in the computational fluid dynamics (CFD) of modeling of soot emission and combustion efficiency (CE) of controlled flares for which experimental soot and CE data are available. The validated CFD modeling tools are useful for oil, gas, and chemical industries to comply with U.S. Environmental Protection Agency's (EPA) mandate to achieve smokeless flaring with a high CE.
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Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Hidrocarbonetos/análise , Hidrodinâmica , Modelos Químicos , Fuligem/análise , Incêndios , Temperatura , Compostos Orgânicos Voláteis/análiseRESUMO
Transplant rejection, like tolerance, is a T cell-dependent event. There is compelling evidence to suggest that induction of transplant tolerance is an actively learned process in which T cells need to engage with the alloantigens in order to learn to tolerate the allograft. A family of cytokines whose receptors use the same IL-2 receptor gammac chain (also called the common gammac) plays an important role in regulating multiple aspects of the allograft response (i.e. rejection vs. tolerance). It is undeniable that gammac cytokines can drive clonal expansion and effector maturation of alloreactive T cells, and therefore, targeting such cytokines or their receptor components remains an attractive way of blocking transplant rejection. However, we just started to appreciate that gammac cytokines also regulate the acquisition of transplant tolerance via programming activated T cells for apoptotic cell death and via guiding the evolution of regulatory T cells. Thus, understanding precisely the role of gammac cytokines in regulating T cell homeostasis and T cell regulation is critically important in the induction of transplant tolerance.
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Citocinas/imunologia , Receptores de Interleucina-2/imunologia , Tolerância ao Transplante/imunologia , Animais , Apoptose/imunologia , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Humanos , Ativação Linfocitária/imunologia , Linfócitos T/imunologia , Transplante HomólogoRESUMO
In this essay, three novel nonlinear optical (NLO) azo-materials containing indole and sulfonyl based chromophores were studied in-depth by using Fourier transform (FT) IR, FT-Raman spectra and density functional theory (DFT). The scaled theoretical results were shown to be in good agreement with the experimental data. In addition, the computed (1)H nuclear magnetic resonance (NMR) and UV-vis absorption wavelengths were also discussed compared with experimental data. The large ß values calculated by the DFT methods showed that the studied molecules were good NLO materials, and the molecule which owned a larger substituent group on the indole chromophore moieties had a larger value. Furthermore, simultaneous infrared and Raman activity suggested that intramolecular charges might transfer through the conjugated framework from the electronic donor group to electronic acceptor group. The HOMO-LUMO gap analysis and molecular electrostatic potential (MEP) maps also supported this viewpoint.
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Compostos Azo/química , Indóis/química , Ácidos Sulfínicos/química , Modelos Moleculares , Dinâmica não Linear , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral RamanRESUMO
The regulatory activities of mouse CD4(+)Foxp3(+) T cells on various immune cells, including NK cells, have been well documented. Under some conditions, conventional CD4(+)Foxp3(-) T cells in the periphery are able to acquire inhibitory function on other T cells, but their roles in controlling innate immune cells are poorly defined. As a potential cellular therapy for cancer, ex vivo activated CD4(+)Foxp3(-) effector T cells are often infused back in vivo to suppress tumor growth and metastasis. Whether such activated T cells could affect NK-cell control of tumorigenesis is unclear. In the present study, we found that mitogen-activated CD4(+)Foxp3(-) T cells exhibited potent suppressor function on NK-cell proliferation and cytotoxicity in vitro, and notably facilitated B16 melanoma metastasis in vivo. Suppression of NK cells by activated CD4(+)Foxp3(-) T cells is cell-cell contact dependent and is mediated by Qa-1:NKG2A interaction, as administration of antibodies blocking either Qa-1 or NKG2A could completely reverse this suppression, and significantly inhibited otherwise facilitated melanoma metastasis. Moreover, activated CD4(+)Foxp3(-) cells from Qa-1 knockout mice completely lost the suppressor activity on NK cells, and failed to facilitate melanoma metastasis when transferred in vivo. Taken together, our findings indicate that innate anti-tumor response is counter regulated by the activation of adaptive immunity, a phenomenon we term as "activation-induced inhibition". Thus, the regulatory role of activated CD4(+)Foxp3(-) T cells in NK-cell activity must be taken into consideration in the future design of cancer therapies.
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Linfócitos T CD4-Positivos/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Células Matadoras Naturais/imunologia , Metástase Neoplásica , Animais , Anticorpos/farmacologia , Linfócitos T CD4-Positivos/imunologia , Linhagem Celular Tumoral , Proliferação de Células , Fatores de Transcrição Forkhead/genética , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Terapia de Imunossupressão , Células Matadoras Naturais/citologia , Células Matadoras Naturais/efeitos dos fármacos , Ativação Linfocitária , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Camundongos Knockout , Camundongos Nus , Camundongos SCID , Subfamília C de Receptores Semelhantes a Lectina de Células NK/imunologia , Subfamília C de Receptores Semelhantes a Lectina de Células NK/metabolismo , Transplante HomólogoRESUMO
In this work, four-second order nonlinear optical (NLO) azobenzene-containing materials are studied in-depth by using vibrational spectra and density functional theory (DFT). The Fourier transform infrared (FT-IR) spectra and FT-Raman spectra are recorded in the range of 50-4000 and 100-3600cm(-1), respectively. Meanwhile, the DFT computations are performed at B3LYP/6-31G (d, p) level to derive equilibrium geometry, vibrational wavenumbers and intensities, and first hyperpolarizability, and the scaled theoretical wavenumbers are also shown to be in good agreement with experimental data. The calculated results show that these four azobenzene-containing compounds are good materials and the compound with nitro substituent groups possesses a larger first molecular hyperpolarizability (ß) value. Moreover, the simultaneous infrared and Raman activation of R1 group and CC stretching suggest that the charge transfer interaction might occur between the R1 group and phenyl ring, and the HOMO-LUMO gap analysis also supports this viewpoint.
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Compostos Azo/química , Modelos Teóricos , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Modelos Moleculares , Estrutura Molecular , Teoria Quântica , VibraçãoRESUMO
PURPOSE: To improve the accuracy of blood loss estimation during extensive escharectomy and auto-microskin grafting on extremities in adult male major burn patients. METHOD: All adult male major burn patients admitted to our center who underwent extensive escharectomy and auto-microskin graft on extremities for more than 10% TBSA during the period 1 January 2008 to 31 December 2009 were involved in this study. The blood loss during the operation was estimated by the surgeons or calculated according to the changes in hemoglobin levels. RESULTS: The average burn and escharectomy areas for the 64 burn patients included in the study were 74.16 ± 16.96% and 30.27 ± 15.63% TBSA respectively. The auto-microskin donor area was 3.81% TBSA. The volumes of intra-operative calculated and estimated blood losses and transfused blood during the operation were 0.47 ml/cm2, 0.13 ml/cm2 and 0.20 ml/cm2 surgical area 77.29 ml, 20.51 ml and 32.83 ml per 1% TBSA), respectively. Within two weeks after injury surgical blood loss appeared to be greater the later the operation was carried out. Within the first week after injury the mean proportional blood loss was increased with area excised. CONCLUSION: In this study the average calculated blood loss for the operation of extensive escharectomy and microskin graft in adult male major burn patient was 0.47 ml/cm2 (77.29 ml per 1% TBSA). This result will help us to predict expected blood loss more accurately.