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141.
Tissue engineering is a promising option for cartilage repair. However, several hurdles still need to be overcome to develop functional tissue constructs suitable for implantation. One of the most common challenges is the general low capacity of chondrocytes to synthesize cartilage-specific extracellular matrix (ECM). While different approaches have been explored to improve the biosynthetic response of chondrocytes, several studies have demonstrated that the nutritional environment (e.g., glucose concentration and media volume) can have a profound effect on ECM synthesis. Thus, the purpose of this study was to optimize the formulation of cell culture media to upregulate the accumulation of cartilaginous ECM constituents (i.e., proteoglycans and collagen) by chondrocytes in 3D culture. Using response surface methodology, four different media factors (basal media, media volume, glucose, and glutamine) were first screened to determine optimal media formulations. Constructs were then cultured under candidate optimal media formulations for 4 weeks and analyzed for their biochemical and structural properties. Interestingly, the maximal accumulation of proteoglycans and collagen appeared to be elicited by different media formulations. Most notably, proteoglycan accumulation was favored by high volume, low glucose-containing DMEM/F12 (1:1) media whereas collagen accumulation was favored by high volume, high glucose-containing F12 media. While high glutamine-containing media elicited increased DNA content, glutamine concentration had no apparent effect on ECM accumulation. Therefore, optimizing the nutritional environment during chondrocyte culture appears to be a promising, straight-forward approach to improve cartilaginous tissue formation. Future work will investigate the combined effects of the nutritional environment and external stimuli.  相似文献   
142.
The tomato (Solanum lycopersicum L.) is one of the world’s most important vegetable crops. Still, phytopathogenic bacteria affect the yield and quality of tomato cultivation, like Agrobacterium tumefeciens (At), Clavibacter michiganensis subsp. michiganensis (Cmm), Pseudomonas syringae pv. tomato (Pst), Ralstonia solanacearum (Rs), and Xanthomonas axonopodis (Xa). Synthetic chemical products are used mostly on disease plant control, but overuse generates resistance to bacterial control. This study aimed to evaluate the in vitro antibacterial activity of the ethanolic extract of Moringa oleifera Lam. leaves against At, Cmm, Pst, Rs, and Xa, as well as information about this plant species’ chemical composition. Antibacterial activity against pathogens observed by microplate technique, phytochemical screening, and FTIR analysis revealed different bio-active compounds on ethanolic extracts with antibacterial activity. The growth inhibition rate ranged between 0.08% and 99.94%. The inhibitory concentration, IC50, required to inhibit 50% of At, Cmm, Pst, Rs, and Xa bacterial growth, was 276.67, 350.48, 277.85, 351.49, and 283.22 mg/L, respectively. Inhibition of phytopathogen bacteria’s growth increased as the concentrations of the extract also increased. Moringa oleifera extract can be recommended as a potent bio-bactericide.  相似文献   
143.
Glycoconjugate Journal - Two recent papers ( https://doi.org/10.1016/j.cell.2021.04.023 and https://doi.org/10.1038/s41586-021-03566-4 ) extend the definition of glycoconjugates to new classes of...  相似文献   
144.
Glycoconjugate Journal - Neisseria meningitidis is a major cause of bacterial meningitidis worldwide. Children less than five years and adolescents are particularly affected. Nearly all invasive...  相似文献   
145.
Neurochemical Research - Gamma-decanolactone (GD) has been shown to reduce epileptic behavior in different models, inflammatory decreasing, oxidative stress, and genotoxic parameters. This study...  相似文献   
146.
In this work, two synthetic aurones revealed moderate schistosomicidal potential in in vitro and in vivo assays. Aurones ( 1 ) and ( 2 ) promoted changes in tegument integrity and motor activity, leading to death of adult Schistosoma mansoni worms in in vitro assays. When administered orally (two doses of 50 mg/kg) in experimentally infected animals, synthetic aurones ( 1 ) and ( 2 ) promoted reductions of 56.20 % and 57.61 % of the parasite load and stimulated the displacement towards the liver of the remaining adult worms. The oogram analysis revealed that the treatment with both aurones interferes with the egg development kinetics in the intestinal tissue. Seeking an action target for compounds ( 1 ) and ( 2 ), the connection with NTPDases enzymes, recognized as important therapeutic targets for S. mansoni, was evaluated. Molecular docking studies have shown promising results. The dataset reveals the anthelmintic character of these compounds, which can be used in the development of new therapies for schistosomiasis.  相似文献   
147.
148.
Brain differential morphogenesis in females is one of the major phenotypic manifestations of caste development in honey bees. Brain diphenism appears at the fourth larval phase as a result of the differential feeding regime developing females are submitted during early phases of larval development. Here, we used a forward genetics approach to test the early brain molecular response to differential feeding leading to the brain diphenism observed at later developmental phases. Using RNA sequencing analysis, we identified 53 differentially expressed genes (DEGs) between the brains of queens and workers at the third larval phase. Since miRNAs have been suggested to play a role in caste differentiation after horizontal and vertical transmission, we tested their potential participation in regulating the DEGs. The miRNA-mRNA interaction network, including the DEGs and the royal- and worker-jelly enriched miRNA populations, revealed a subset of miRNAs potentially involved in regulating the expression of DEGs. The interaction of miR-34, miR-210, and miR-317 with Takeout, Neurotrophin-1, Forked, and Masquerade genes was experimentally confirmed using a luciferase reporter system. Taken together, our results reconstruct the regulatory network that governs the development of the early brain diphenism in honey bees.  相似文献   
149.
BackgroundHigh tumor infiltrating lymphocytes (TILs) density was previously shown to be associated with favorable prognosis for patients with colon cancer (CC). However, the impact of TILs on overall survival (OS) of stage II CC patients who received adjuvant chemotherapy (ADJ) or not (no-ADJ) is unknown. We assessed the prognostic value of CD3+ TILs in stage II CC patients according to whether they had ADJ or not.MethodsPatients treated with curative surgery for stage II CC (2002–2013) were selected from the Santa Maria alle Scotte Hospital registry. TILs at the invasive front, center of tumor, and stroma were determined by immunohistochemistry and manually quantified as the rate of TILs/total tissue areas. High TILs (H-TILs) was defined as >20%. Patients were categorized as high or low TILs (L-TILs) and ADJ or no-ADJ.ResultsOf the 678 patients included, 137 (20%) received ADJ and 541 (80%) did not. The distribution of the 4 groups were: 16% (L-TIL/ADJ), 64% (L-TIL/no-ADJ), 5% (H-TIL/ADJ), 15% (H-TIL/no-ADJ). Compared to H-TILs/no-ADJ, ADJ patients showed a significantly increased OS (P<.01) regardless of the TILs rate whereas L-TILs/no-ADJ had significantly decreased OS and higher risk of death (HR=1.41; 95% CI, 1.06–1.88; P<.0001). On multivariable analysis, the unfavorable prognostic value of L-TILs (vs. H-TILs) for no-ADJ patients was confirmed (HR=1.36; 95% CI 1.02, 1.82; P=.0373).ConclusionLow CD3+ TILs rate was associated with shorter OS in those with stage II colon cancer who did not receive adjuvant therapy. Low CD3+ TILs could be considered an additional risk factor for still ADJ-untreated stage II CC patients, which could facilitate clinical decision making.  相似文献   
150.
Point 1: Stereo‐video camera systems (SVCSs) are a promising tool to remotely measure body size of wild animals without the need for animal handling. Here, we assessed the accuracy of SVCSs for measuring straight carapace length (SCL) of sea turtles.Point 2: To achieve this, we hand captured and measured 63 juvenile, subadult, and adult sea turtles across three species: greens, Chelonia mydas (n = 52); loggerheads, Caretta caretta (n = 8); and Kemp''s ridley, Lepidochelys kempii (n = 3) in the waters off Eleuthera, The Bahamas and Crystal River, Florida, USA, between May and November 2019. Upon release, we filmed these individuals with the SVCS. We performed photogrammetric analysis to extract stereo SCL measurements (eSCL), which were then compared to the (manual) capture measurements (mSCL).Point 3: mSCL ranged from 25.9 to 89.2 cm, while eSCL ranged from 24.7 to 91.4 cm. Mean percent bias of eSCL ranged from −0.61% (±0.11 SE) to −4.46% (±0.31 SE) across all species and locations. We statistically analyzed potential drivers of measurement error, including distance of the turtle to the SVCS, turtle angle, image quality, turtle size, capture location, and species.Point 4: Using a linear mixed effects model, we found that the distance between the turtle and the SVCS was the primary factor influencing measurement error. Our research suggests that stereo‐video technology enables high‐quality measurements of sea turtle body size collected in situ without the need for hand‐capturing individuals. This study contributes to the growing knowledge base that SVCS are accurate for body size measurements independent of taxonomic clade.  相似文献   
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