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1.
APL Bioeng ; 8(2): 021505, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38841690

RESUMO

The myotendinous junction (MTJ) is the interface connecting skeletal muscle and tendon tissues. This specialized region represents the bridge that facilitates the transmission of contractile forces from muscle to tendon, and ultimately the skeletal system for the creation of movement. MTJs are, therefore, subject to high stress concentrations, rendering them susceptible to severe, life-altering injuries. Despite the scarcity of knowledge obtained from MTJ formation during embryogenesis, several attempts have been made to engineer this complex interfacial tissue. These attempts, however, fail to achieve the level of maturity and mechanical complexity required for in vivo transplantation. This review summarizes the strategies taken to engineer the MTJ, with an emphasis on how transitioning from static to mechanically inducive dynamic cultures may assist in achieving myotendinous maturity.

2.
Heliyon ; 9(6): e16413, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37484377

RESUMO

Knowledge of the dynamics of vegetation phenology is essential for the understanding of vegetation-climate interactions. Although the interest in phenology study is growing, vegetation phenology in Africa received far less attention compared to the Northern Hemisphere. Africa straddles the northern and southern hemispheres, and the climate has a clear latitudinal gradient, which facilitates the study of the interaction between phenology and climate. In this study, the latitudinal and longitudinal gradients and temporal trends of start of growing season (SOS), peak of growing season (POS), and end of growing season (EOS) were examined using long-term satellite dataset during 1982-2015. The latitudinal variations in these phenology metrics were larger in the northern than those in the southern Africa, especially from 6°N northwards to 16°N. The latitudinal variations in southern Africa had no clear patterns due to the more complex climate systems. For the longitudinal variation, the temporal trends in POS and EOS exhibited a gradient-decreasing rate in northern Africa. Over the period from 1982 to 2015, the overall trends of the phenology in Africa were 'later SOS', 'later POS', and 'later EOS'. The faster rate of delay in EOS than in SOS resulted in a prolonged length of growing season (LOS) with 0.50 days/year on average in northern Africa, while a slower rate of delay in EOS than in SOS resulted in a shorter LOS with -0.12 days/year in southern Africa. The prolonged LOS in northern Africa contributes to the increase in the yearly-averaged Normalized Difference Vegetation Index (NDVI) from 1982 to 2000. Nevertheless, the NDVI appeared to have reached saturation around the 2000s, although the LOS was still extending after 2000s. Overall, the findings of this study provide an overall view of the spatial and temporal patterns of land surface phenology in the African continent, and a necessary component for future studies on the response of phenology to climate.

3.
Insect Biochem Mol Biol ; 140: 103701, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34890799

RESUMO

Insect cuticular hydrocarbons (CHCs) have dual functions as physical barrier and chemical signals. The last step of CHC biosynthesis is known to be catalyzed by cytochrome P450 CYP4G in a number of insects. Until recently, studies on CYP4Gs in the context of functional evolution are rare. In this study, we analyzed sequence similarity and temporal-spatial expression patterns of the five CYP4G genes in the cotton bollworm Helicoverpa armigera, an important agricultural pest and also typical representative of lepidopteran insects. Moreover, the CRISPR/Cas9-induced knockout was used to clarify the roles of the five CYP4Gs in CHC biosynthesis. Temporal-spatial expression patterns revealed that CYP4G8 was highly expressed at all developmental stages and in most tissues examined. Larvae with CYP4G8 knocked out could not produce methyl-branched CHCs and failed to pupate, while larvae with the other four CYP4G genes knocked out (4G1-type-KO) showed no significant changes in their CHC profiles, weight gain and survival. Comparative transcriptomics revealed that knocking out CYP4G8 affected the global gene expression in larvae, especially down-regulated the expression of genes in the fatty acid biosynthetic pathway, while no significant change in 4G1-type-KO transcriptome was observed. These findings indicate that the five members of the CYP4G subfamily have undergone functional divergence: CYP4G8 maintains the essential function in CHC biosynthesis, while the function of the other four CYP4G genes remains unclear. Intriguingly, CYP4G8 has evolved to be a P450 enzyme responsible for the synthesis of larval methyl-branched hydrocarbons. The observation that CYP4G8 knockout is lethal strongly suggest that CYP4G8 may serve as a candidate target for the development of insecticidal agents for the control of cotton bollworms.


Assuntos
Sistema Enzimático do Citocromo P-450 , Hidrocarbonetos/metabolismo , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Insetos/metabolismo , Larva/metabolismo , Mariposas/metabolismo , Transcriptoma
4.
Data Brief ; 39: 107600, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34901341

RESUMO

Recent advances in leaf fluorescence measurements and canopy proximal remote sensing currently enable the non-destructive collection of rich diurnal and seasonal time series, which are required for monitoring vegetation function at the temporal and spatial scales relevant to the natural dynamics of photosynthesis. Remote sensing assessments of vegetation function have traditionally used actively excited foliar chlorophyll fluorescence measurements, canopy optical reflectance data and vegetation indices (VIs), and only recently passive solar induced chlorophyll fluorescence (SIF) measurements. In general, reflectance data are more sensitive to the seasonal variations in canopy chlorophyll content and foliar biomass, while fluorescence observations more closely relate to the dynamic changes in plant photosynthetic function. With this dataset we link leaf level actively excited chlorophyll fluorescence, canopy proximal reflectance and SIF, with eddy covariance measurements of gross ecosystem productivity (GEP). The dataset was collected during the 2017 growing season on maize, using three automated systems (i.e., Monitoring Pulse-Amplitude-Modulation fluorimeter, Moni-PAM; Fluorescence Box, FloX; and from eddy covariance tower). The data were quality checked, filtered and collated to a common 30 minutes timestep. We derived vegetation indices related to canopy functioning (e.g., Photochemical Reflectance Index, PRI; Normalized Difference Vegetation Index, NDVI; Chlorophyll Red-edge, Clre) to investigate how SIF and VIs can be coupled for monitoring vegetation photosynthesis. The raw datasets and the filtered and collated data are provided to enable new processing and analyses.

5.
Remote Sens Environ ; 264: 112609, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34602655

RESUMO

Remote sensing-based measurements of solar-induced chlorophyll fluorescence (SIF) are useful for assessing plant functioning at different spatial and temporal scales. SIF is the most direct measure of photosynthesis and is therefore considered important to advance capacity for the monitoring of gross primary production (GPP) while it has also been suggested that its yield facilitates the early detection of vegetation stress. However, due to the influence of different confounding effects, the apparent SIF signal measured at canopy level differs from the fluorescence emitted at leaf level, which makes its physiological interpretation challenging. One of these effects is the scattering of SIF emitted from leaves on its way through the canopy. The escape fraction ( f esc ) describes the scattering of SIF within the canopy and corresponds to the ratio of apparent SIF at canopy level to SIF at leaf level. In the present study, the fluorescence correction vegetation index (FCVI) was used to determine f esc of far-red SIF for three structurally different crops (sugar beet, winter wheat, and fruit trees) from a diurnal data set recorded by the airborne imaging spectrometer HyPlant. This unique data set, for the first time, allowed a joint analysis of spatial and temporal dynamics of structural effects and thus the downscaling of far-red SIF from canopy ( SIF 760 canopy ) to leaf level ( SIF 760 leaf ). For a homogeneous crop such as winter wheat, it seems to be sufficient to determine f esc once a day to reliably scale SIF760 from canopy to leaf level. In contrast, for more complex canopies such as fruit trees, calculating f esc for each observation time throughout the day is strongly recommended. The compensation for structural effects, in combination with normalizing SIF760 to remove the effect of incoming radiation, further allowed the estimation of SIF emission efficiency ( ε SIF ) at leaf level, a parameter directly related to the diurnal variations of plant photosynthetic efficiency.

6.
Cell Physiol Biochem ; 39(2): 521-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27383764

RESUMO

BACKGROUND/AIMS: To evaluate the prognostic significance of monocytes and monocytic myeloid-derived suppressor cells (M-MDSCs) for patients with diffuse large B-cell lymphoma (DLBCL) under R-CHOP chemotherapy. METHODS: Flow cytometry (FCM) was applied to measure M-MDSCs (CD14+ HLA-DRlow/- M-MDSCs). RESULTS: Analysis of 144 patients with DLBCL under R-CHOP treatment showed that the 5-year overall survival rate was 61.09% (95% CI: 43.72%-72.56%) and the average survival time of patients with monocytes (%) ≥ 8% was shorter than those with monocytes (%) < 8% (P = 0.0036). Further stratified analysis suggested that the average survival time of patients with monocytes (%) ≥ 8% was shorter than patients with monocytes (%) < 8% in the moderate outcome group (R-IPI = 1, 2) (P = 0.0168) and in the poorest outcome group (R-IPI > 2) (P = 0.0397), meanwhile, there was no significant difference in survival of patients with monocytes (%) ≥ 8% compared to patients with monocytes (%) < 8% in the best outcome group (R-IPI = 0) (P = 0.3106). Both of monocytes (%) and M-MDSCs were decreased in different R-IPI groups after 4-course of R-CHOP chemotherapy (P < 0.05). CONCLUSION: Our results indicated that monocytes (%) and M-MDSCs combined with R-IPI may be a simple and efficient immunological index to evaluate prognosis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Monócitos/efeitos dos fármacos , Células Supressoras Mieloides/efeitos dos fármacos , Adulto , Idoso , Anticorpos Monoclonais Murinos/administração & dosagem , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Citometria de Fluxo , Humanos , Estimativa de Kaplan-Meier , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Células Supressoras Mieloides/metabolismo , Prednisona/administração & dosagem , Prognóstico , Indução de Remissão , Resultado do Tratamento , Vincristina/administração & dosagem , Adulto Jovem
7.
Sensors (Basel) ; 16(4)2016 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-27058542

RESUMO

Significant research progress has recently been made in estimating fluorescence in the oxygen absorption bands, however, quantitative retrieval of fluorescence data is still affected by factors such as atmospheric effects. In this paper, top-of-atmosphere (TOA) radiance is generated by the MODTRAN 4 and SCOPE models. Based on simulated data, sensitivity analysis is conducted to assess the sensitivities of four indicators-depth_absorption_band, depth_nofs-depth_withfs, radiance and Fs/radiance-to atmospheric parameters (sun zenith angle (SZA), sensor height, elevation, visibility (VIS) and water content) in the oxygen absorption bands. The results indicate that the SZA and sensor height are the most sensitive parameters and that variations in these two parameters result in large variations calculated as the variation value/the base value in the oxygen absorption depth in the O2-A and O2-B bands (111.4% and 77.1% in the O2-A band; and 27.5% and 32.6% in the O2-B band, respectively). A comparison of fluorescence retrieval using three methods (Damm method, Braun method and DOAS) and SCOPE Fs indicates that the Damm method yields good results and that atmospheric correction can improve the accuracy of fluorescence retrieval. Damm method is the improved 3FLD method but considering atmospheric effects. Finally, hyperspectral airborne images combined with other parameters (SZA, VIS and water content) are exploited to estimate fluorescence using the Damm method and 3FLD method. The retrieval fluorescence is compared with the field measured fluorescence, yielding good results (R² = 0.91 for Damm vs. SCOPE SIF; R² = 0.65 for 3FLD vs. SCOPE SIF). Five types of vegetation, including ailanthus, elm, mountain peach, willow and Chinese ash, exhibit consistent associations between the retrieved fluorescence and field measured fluorescence.

8.
Br J Pharmacol ; 171(24): 5845-57, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25164592

RESUMO

BACKGROUND AND PURPOSE: The transporter, multidrug resistance protein 1 (MRP1, ABCC1), plays a critical role in the development of multidrug resistance (MDR). Ibrutinib is an inhibitor of Bruton's tyrosine kinase. Here we investigated the reversal effect of ibrutinib on MRP1-mediated MDR. EXPERIMENTAL APPROACH: Cytotoxicity was determined by MTT assay. The expression of protein was detected by Western blot. RT-PCR and Q-PCR were performed to detect the expression of MRP1 mRNA. The intracellular accumulation and efflux of substrates for MRP1 were measured by scintillation counter and flow cytometry. HEK293/MRP1 cell xenografts in nude mice were established to study the effects of ibrutinib in vivo. KEY RESULTS: Ibrutinib significantly enhanced the cytotoxicity of MRP1 substrates in HEK293/MRP1 and HL60/Adr cells overexpressing MRP1. Furthermore, ibrutinib increased the accumulation of substrates in these MRP1-overexpressing cells by inhibiting the drug efflux function of MRP1. However, mRNA and protein expression of MRP1 remained unaltered after treatment with ibrutinib in MRP1-overexpressing cells. In vivo, ibrutinib enhanced the efficacy of vincristine to inhibit the growth of HEK293/MRP1 tumour xenografts in nude mice. Importantly, ibrutinib also enhances the cytotoxicity of vincristine in primary cultures of leukaemia blasts, derived from patients. CONCLUSIONS AND IMPLICATIONS: Our results indicated that ibrutinib significantly increased the efficacy of the chemotherapeutic agents which were MRP1 substrates, in MRP1-overexpressing cells, in vitro, in vivo and ex vivo. These findings will lead to further studies on the effects of a combination of ibrutinib with chemotherapeutic agents in cancer patients overexpressing MRP1.


Assuntos
Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirazóis/farmacologia , Pirimidinas/farmacologia , RNA Mensageiro/efeitos dos fármacos , Adenina/análogos & derivados , Tirosina Quinase da Agamaglobulinemia , Animais , Antineoplásicos/farmacologia , Células HEK293 , Células HL-60 , Humanos , Técnicas In Vitro , Camundongos , Camundongos Nus , Piperidinas , RNA Mensageiro/metabolismo , Vincristina/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(9): 2451-4, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24369651

RESUMO

Dataset simulated with FluorMOD and images of wheat in heading stage taken by a ground-based hyperspectral imaging system with 3.3 nm spectral resolution and 0. 71-0. 74 nm spectral sampling interval were used test the feasibility and accuracy of three FLD methods (named FLD, 3FLD and iFLD). The results show that when spectral resolution is 3.3 nm, solar-induced chlorophyll fluorescence could be extracted effectively in O2-A band (around 760 nm) instead of O2-B band (around 687 nm). As to the extraction results of data with noises, both FLD and 3FLD are stabler than iFLD method. The results of FLD tend to be higher than true value.


Assuntos
Clorofila/análise , Espectrometria de Fluorescência , Triticum/química , Fluorescência , Folhas de Planta , Luz Solar
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(11): 3101-5, 2013 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-24555390

RESUMO

The solar-induced chlorophyll fluorescence (ChlF) has a close relationship with photosynthetic and is considered as a probe of plant photosynthetic activity. In this study, an airborne fluorescence detecting system was constructed by using a hyperspectral imager on board an unmanned airship. Both Fraunhofer Line Discriminator (FLD) and 3FLD used to extract ChlF require the incident solar irradiance, which is always difficult to receive at airborne level. Alternative FLD (aFLD) can overcome the problem by selecting non-fluorescent emitter in the image. However, aFLD is based on the assumption that reflectance is identical around the Fraunhofer line, which is not realistic. A new method, a3FLD, is proposed, which assumes that reflectance varies linearly with the wavelength around Fraunhofer line. The result of simulated data shows that ChlF retrieval error of a3FLD is significantly lower than that of aFLD when vegetation reflectance varies near the Fraunhofer line. The results of hyperspectral remote sensing data with the airborne fluorescence detecting system show that the relative values of retrieved ChlF of 5 kinds of plants extracted by both aFLD and a3FLD are consistent with vegetation growth stage and the ground-level ChlF. The ChlF values of aFLD are about 15% greater than a3FLD. In addition, using aFLD, some non-fluorescent objects have considerable ChlF value, while a3FLD can effectively overcome the problem.


Assuntos
Clorofila/análise , Monitoramento Ambiental , Plantas , Tecnologia de Sensoriamento Remoto/instrumentação , Tecnologia de Sensoriamento Remoto/métodos , Fluorescência , Fotossíntese , Espectrometria de Fluorescência
11.
Clin Invest Med ; 33(5): E290-7, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20926035

RESUMO

PURPOSE: Metabolic syndrome (MS) and type 2 diabetes mellitus (T2DM) are complex diseases affected by both dietary intake and genetic background. Whether N-5, 10-methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism, high-sensitivity C-reactive protein (hs-CRP) and dietary components folate and vitamin B12 are associated with MS in Asian has not been determined. METHODS: We hypothesized that MTHFR gene C677T, folate, vitamin B12 and hs-CRP are associated with MS and factors related to MS in northern Han Chinese. To test this hypothesis, MTHFR C677T gene polymorphism was determined by PCR-RFLP, serum insulin, folate and vitamin B12 levels by radioimmunoassay, and hs-CRP by immunoturbidimetry in newly diagnosed T2DM patients with MS (118) and without MS (40), and in 55 healthy subjects. RESULTS: Results indicated that MS-associated T2DM accounts for 75% of newly diagnosed T2DM in Han Chinese. Serum hs-CRP was higher and serum vitamin B12 was lower in subjects with TT genotype in comparison with those with CC or CT genotypes. Total T frequency was significantly higher in MS-associated T2DM patients (45.3%) compared to 26.3% in non-MS-associated T2DM patients. MTHFR C677T gene polymorphism and vitamin B12 levels were associated with MS-associated T2DM. CONCLUSION: MTHFR C677T gene polymorphism may contribute to insulin resistance in Han Chinese with MS by increasing hs-CRP and decreasing vitamin B12, and consequently play an important role in development of MS-associated T2DM.


Assuntos
Proteína C-Reativa/metabolismo , Predisposição Genética para Doença/genética , Resistência à Insulina/genética , Síndrome Metabólica/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo Genético/genética , Vitamina B 12/sangue , Idoso , Povo Asiático , Feminino , Ácido Fólico/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Radioimunoensaio
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