Acetate Incorporation Research Articles

Implant dynamics, inner structure, and their impact on drug release of in situ forming implants uncovered through CT imaging

In situ forming implants (ISFIs) composed of biodegradable polymers and biocompatible solvents are generally designed for sustained drug release. In this study, a non-invasive computed tomography (CT) imaging approach is used to achieve real time imaging of ISFIs in vivo and in vitro using leuprolide acetate in situ forming implant as a model drug product. The process of implant formation, inner structure change and their impact on drug release were elucidated. Real-time drug distribution was unveiled by the CT contrast agent, iohexol, where it shows a core-shell structure of the deposition. The incorporation of leuprolide acetate (LA) led to a reduced extent of burst release, prolongated release profile, and extended implant size expansion. LA was found to interact with the solvent and slowed down the polymer phase inversion, thus significantly changed the drug distribution in the implant and reduced the drug release. The implant inner structure identified through SEM, implant size change, and polymer degradation along with the CT real time imaging all consistently support the implant formation differences and their implant on the drug release. Similar patterns of implant size expansion and iohexol distribution in the implants were observed both in vitro and in vivo for the implants with and without LA. The comprehensive understanding of the impact of implant formation on drug release through real time CT imaging facilitates the ISFI product development and evaluation.

Recovery of Soil Microbial Metabolism After Rewetting Depends on Interacting Environmental Conditions and Changes in Functional Groups and Life History Strategies.

Climate change is causing an intensification of soil drying and rewetting events, altering microbial functioning and potentially destabilizing soil organic carbon. After rewetting, changes in microbial community carbon use efficiency (CUE), investment in life history strategies, and fungal to bacterial dominance co-occur. Still, we have yet to generalize what drives these dynamic responses. Here, we collated 123 time series of microbial community growth (G, sum of fungal and bacterial growth, evaluated by leucine and acetate incorporation, respectively) and respiration (R) after rewetting and calculated CUE = G/(G + R). First, we characterized CUE recovery by two metrics: maximum CUE and time to maximum CUE. Second, we translated microbial growth and respiration data into microbial investments in life history strategies (high yield (Y), resource acquisition (A), and stress tolerance (S)). Third, we characterized the temporal change in fungal to bacterial dominance. Finally, the metrics describing the CUE recovery, investment in life history strategies, and fungal to bacterial dominance after rewetting were explained by environmental factors and microbial properties. CUE increased after rewetting as fungal dominance declined, but the maximum CUE was explained by the CUE under moist conditions, rather than specific environmental factors. In contrast, higher soil pH and carbon availability accelerated the decline of microbial investment in stress tolerance and fungal dominance. We conclude that microbial CUE recovery is mostly driven by the shifting microbial community composition and the metabolic capacity of the community, whereas changes in microbial investment in life history strategies and fungal versus bacterial dominance depend on soil pH and carbon availability.

Enhancement of Tricyclazole Analysis Efficiency in Rice Samples Using an Improved QuEChERS and Its Application in Residue: A Study from Unmanned Arial Spraying

Enhancements to the analytical method for the determination of tricyclazole in rice samples have been applied to monitor residues during unmanned aerial spraying. The acetonitrile extraction technique QuEChERS was improved by the incorporation of ethyl acetate and 0.1% formic acid, which significantly elevated the recovery rates. Furthermore, the purification process was refined by integrating both primary–secondary amine (PSA) and C18 in the dSPE method, achieving a substantial improvement in reducing matrix effects (MEs) and increasing recovery efficiency. The optimized method demonstrated an impressive % ME value at −3.1%, with a limit of quantitation (LOQ) established at 0.01 mg/kg, and recovery rates between 94.7 and 95.6% at 0.01, 0.1, and 2 mg/kg. Using two types of adjuvants (stickers) during multi-copter spraying markedly improved the initial tricyclazole deposition on rice panicles, with residue levels initially increasing from 0.35 mg/kg to between 0.68 and 1.60 mg/kg. Residues in hulled rice at harvest (10 days post-application) remained well below the maximum residue limit (MRL) of 0.7 mg/kg, ranging from 0.02 to 0.11 mg/kg, thus affirming the safety and efficacy of adjuvants in residue management.

Synergetic Optimization of Upper and Lower Surfaces of the SnO2 Electron Transport Layer for High-Performance n-i-p Perovskite Solar Cells.

The SnO2 electron transport layer (ETL) has been recognized as one of the most effective protocols for achieving high-efficiency perovskite solar cells (PSCs). To date, most research has primarily focused on the modification of the upper surface of SnO2 ETL films. The lower surface of the SnO2 film, which directly influences the film formation of solution-processed SnO2, is equally important but receives relatively less attention. Herein, we present a synergetic optimization approach involving the deposition of aluminum oxide (AlOx) via atomic layer deposition (ALD) as a buffer layer and the incorporation of rubidium acetate (RbAc) as an upper surface passivation additive. This process leads to a conformal coating of SnO2 nanoparticles, improved electrical performance, and higher-quality perovskite crystals. As a result, with this composite ETL film, the power conversion efficiency (PCE) reached 22.41 from 20.77%. Further modification with p-butyl iodide (BAI) on the perovskite upper surface increased the champion PCE to 23.32%, with a voltage loss of 0.41 V, ranking among the lowest values for the triple-cation mixed-halide perovskite absorber (1.58 eV). Importantly, the perovskite solar cells remained 87.30% of its initial performance after 14 days of aging and exhibited photostability under long-term UV (254 nm) illumination.

Study on the evolutionary mechanism of shrinkage stress-strain behavior of EVA-modified cement mortar at an early age

Understanding the early deformation characteristics is important to predict early cracks in cementitious materials and to serve structural engineering. Incorporation of polyethylene-vinyl acetate (EVA) dispersible polymer powder can improve the early cracking of cementitious materials. In this paper, the homogeneity, shrinkage stress-strain behavior and the evolutionary mechanism of EVA-modified cement mortar (EMCM) with different polymer-to-cement ratios (p/c) were investigated at an early age. The homogeneity and shrinkage stress-strain behavior of EMCM were characterized by a self-designed test setup. Isothermal calorimetric analysis, scanning electron microscopy and X-ray diffraction were used for the evolutionary mechanism analysis. The results show that the homogeneity of shrinkage of EMCM can be improved by adding EVA and prolonging the mixing time. The shrinkage stress of EMCM can be reduced by 83 % when p/c is 10 % and 15 %. Meanwhile, the elastic modulus of mortar can be reduced by 45 % when the EVA content is 15 %. Isothermal calorimetric analysis and characterization of microscopic properties show that EVA can inhibit both the generation and conversion of C4AH13, as well as the generation of AFt and CH, and retard the hydration of cement mortar. Within 3 h of hydration, the change in shrinkage stress of EMCM is only affected by the amount of AFt generated, while the change in shrinkage strain is affected by both CH and AFt generation, and the correlation with CH is greater. Finally, the interpenetrating network structure between the EVA and the cementitious matrix increases the interaction and bond between them, giving good deformability and thus reducing shrinkage. Therefore, the reduction in shrinkage stress-strain of EMCM is a result of the combined effect of the polymer on delaying cement hydration and increasing internal interaction and bonding.

Acetyl-CoA synthetase 2 contributes to a better prognosis for liver cancer by switching acetate-glucose metabolism

Acetyl-CoA synthetase 2 (ACSS2)-dependent acetate usage has generally been associated with tumorigenesis and increased malignancy in cancers under nutrient-depleted conditions. However, the nutrient usage and metabolic characteristics of the liver differ from those of other organs; therefore, the mechanism of ACSS2-mediated acetate metabolism may also differ in liver cancer. To elucidate the underlying mechanisms of ACSS2 in liver cancer and acetate metabolism, the relationships between patient acetate uptake and metabolic characteristics and between ACSS2 and tumor malignancies were comprehensively studied in vitro, in vivo and in humans. Clinically, we initially found that ACSS2 expression was decreased in liver cancer patients. Moreover, PET-CT imaging confirmed that lower-grade cancer cells take up more 11C-acetate but less 18F-fluorodeoxyglucose (18F-FDG); however, this trend was reversed in higher-grade cancer. Among liver cancer cells, those with high ACSS2 expression avidly absorbed acetate even in a glucose-sufficient environment, whereas those with low ACSS2 expression did not, thereby showing correlations with their respective ACSS2 expression. Metabolomic isotope tracing in vitro and in vivo revealed greater acetate incorporation, greater lipid anabolic metabolism, and less malignancy in high-ACSS2 tumors. Notably, ACSS2 downregulation in liver cancer cells was associated with increased tumor occurrence in vivo. In human patient cohorts, patients in the low-ACSS2 subgroup exhibited reduced anabolism, increased glycolysis/hypoxia, and poorer prognosis. We demonstrated that acetate uptake by ACSS2 in liver cancer is independent of glucose depletion and contributes to lipid anabolic metabolism and reduced malignancy, thereby leading to a better prognosis for liver cancer patients.

Acetate ion-intercalated NiCo-LDH with quasi-theoretical capacitance for high energy/power density aqueous supercapacitors

One-step solvothermal method is used to produce Ni0.7Co0.3-LDH intercalated with acetate. The incorporation of Co and acetate regulates pore size distribution and heterogeneous electron configuration, facilitating ion diffusion and redox activity.

Fabrication of polycaprolactone electrospun fibres with retinyl acetate for antioxidant delivery in a ROS-mimicking environment.

Background: Increased cancer rates denote that one in two people will be diagnosed with cancer in their lifetime. Over 60% of cancer patients receive radiotherapy, either as a stand-alone treatment or in combination with other treatments such as chemotherapy and surgery. Whilst radiotherapy is effective in destroying cancer cells, it also causes subsequent damage to healthy cells and surrounding tissue due to alterations in the tumor microenvironment and an increase in reactive oxygen species (ROS). This can cause extensive damage that impairs tissue function, and the likelihood of tissue regeneration and restoration of function is significantly reduced as new healthy cells cannot survive in the damaged environment. In the treatment of head and neck cancers, radiotherapy can cause salivary gland dysfunction. This significantly impairs the patient's quality of life and there is currently no cure, only palliative treatment options. Tissue engineering approaches are used to mimic the microenvironment of the tissue and can mediate the damaged microenvironment via bioactive compounds, to support the delivery, survival, and proliferation of new, healthy cells into the damaged environment. Methods: In this study, retinyl acetate, a derivative of vitamin A, was successfully incorporated into electrospun polycaprolactone fibres. Results: SEM images and characterization analyses showed that all scaffolds produced had similar characteristics, including fiber morphology and scaffold wettability. The vitamin scaffolds were shown to exert an antioxidant effect through scavenging activity of both DPPH and hydroxyl radicals in vitro. Critically, the antioxidant scaffolds supported the growth of human submandibular gland cells and significantly upregulated the expression of GPx1, an antioxidant enzyme, when cultured under both normal conditions and under a simulated oxidative stress environment. Discussion: These results suggest that incorporation of retinyl acetate into electrospun fibres has may mediate the damaged microenvironment post cancer radiation therapy.

Investigating A Multi-Domain Polyketide Synthase in Amphidinium carterae.

Dinoflagellates are unicellular organisms that are implicated in harmful algal blooms (HABs) caused by potent toxins that are produced through polyketide synthase (PKS) pathways. However, the exact mechanisms of toxin synthesis are unknown due to a lack of genomic segregation of fat, toxins, and other PKS-based pathways. To better understand the underlying mechanisms, the actions and expression of the PKS proteins were investigated using the toxic dinoflagellate Amphidinium carterae as a model. Cerulenin, a known ketosynthase inhibitor, was shown to reduce acetate incorporation into all fat classes with the toxins amphidinol and sulpho-amphidinol. The mass spectrometry analysis of cerulenin-reacted synthetic peptides derived from ketosynthase domains of A. carterae multimodular PKS transcripts demonstrated a strong covalent bond that could be localized using collision-induced dissociation. One multi-modular PKS sequence present in all dinoflagellates surveyed to date was found to lack an AT domain in toxin-producing species, indicating trans-acting domains, and was shown by Western blotting to be post-transcriptionally processed. These results demonstrate how toxin synthesis in dinoflagellates can be differentiated from fat synthesis despite common underlying pathway.

Unraveling the Cancer Metabolism: Fasting Reset, Ketogenic Diet? and Therapeutic Strategies

Cancer cells harness a mechanism known as ketolysis to generate energy, a process that involves the enzymes SCOT and ACAT1, instrumental in the creation of a crucial molecule named acetyl-CoA. This molecule plays a vital role in cellular energy production. Interestingly, cancer cells are capable of alternative methods for generating acetyl-CoA, such as the incorporation of external acetate. Although restraining the function of SCOT and ACAT1 may decelerate cancerous growth, it could potentially impede the tumor cells’ ability to produce necessary new membranes for their survival.

Long-term hypoxia exposure impairs metabolic pathways of de novo lipogenesis in young mouse adipocytes

Introduction: Obstructive sleep apnea syndrome, manifested by tissue hypoxia, is causally linked with the development of metabolic diseases such as Type 2 diabetes. Although there is convincing epidemiological evidence, molecular mechanisms mediating the adverse metabolic effects remain unclear. Hypoxia may play an important role and modulate metabolic pathways in young adipocytes including the utilization of glucose and acetate or the activation of the reverse tricarboxylic acid cycle (rTCA) leading to increase de novo lipogenesis and excessive fat accumulation. The aim of this study was to investigate the impact of long-term hypoxia on important pathways of de novo lipogenesis in mouse early and late adipocytes. Hypothesis: Hypoxia affects the utilization of carbon sources for de novo lipogenesis differently in early and late adipocytes. Methods: Mouse 3T3-L1 cells were differentiated into adipocytes for 7 days - early adipocytes (EA) or 14 days - late adipocytes (LA). The cells were cultured in gas-permeable cultureware allowing exposure to sustained oxygen levels of 21% O 2 or 4% O 2 . [ 13 C-5]-glutamine (2.5mM) was added to culture media for 7 and 14 days to assess 13 C incorporation to newly synthesized lipids via rTCA and [ 13 C-1]-glutamine (2.5mM) was added to media for 24h to assess 13 C incorporation to rTCA metabolites. The 13 C incorporation studies were analyzed via gas chromatography-mass spectrometry. The contribution of glucose and acetate to de novo lipogenesis was assessed using [ 14 C]-glucose and [ 14 C]-acetate (both 0.2 μCi) provided in culture media for 2h at the end of experiments. Subsequently, radioactivity in extracted lipids was measured via scintillation counter. Statistical significance was assessed by 2-way ANOVA followed by Tukey's test. Data are presented as means ± SD, N=9. Data Hypoxia had no effect on lipid accumulation in EA, lipid accumulation in LA was increased by 134,41% vs control. The 13 C incorporation to lipids was increased in EA by 42,2% vs control and by 13,33% vs LA. The 13 C incorporation in citrate was increased by 8,71%, in malate by 9,58% in EA vs control, in LA the incorporation remained unchanged. The [ 14 C]-glucose incorporation to lipids was elevated in EA vs control by 209,98% and EA vs LA by 60,02%. The [ 14 C]-acetate incorporation to lipids was increased in EA by 198,43% vs control and decreased by 45,13% vs LA. Differences are statistically significant (p <0.05). Summary: The effect of hypoxia on lipid accumulation was observed at the late stages of adipocyte maturation. However, in EA hypoxia initially stimulated the activation of rTCA to partially contribute to de novo lipogenesis and significantly increased 14 C-glucose incorporation. In LA the rTCA and 14 C-glucose incorporation were reduced to the control level and the contribution of acetate was increased. Conclusion: Hypoxia modified metabolic pathways in maturating adipocytes leading to increased de novo lipogenesis and thus hypertrophic mature adipocytes. Project was supported by Grant Agency of the Charles University project GAUK 294822 and by grant AZV project NU21-01-00259 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Pathway to the Polyvinyl‐Acetate‐Assisted PEDOT:PSS as a Dopant‐Free Hole Transporting Material in Planar Heterojunction Perovskite Solar Cells

To achieve world's burgeoning appetite in obtaining high‐energy conversion efficiency, not only perovskite semiconductor but also hole transporting material (HTM) takes a significant role as a game changer. The dopant of conventional organic HTM induces side effects of degradation, and inorganic HTM reacts or penetrates with the underlying perovskite layer. Considering those issues, poly(3,4‐ethylenedioxythiophene:poly(styrene sulfonate) (PEDOT:PSS) as an alternative HTM has been explored in the field of perovskite solar cells with its outstanding hole transporting property. Herein, incorporation of polyvinyl acetate (PVAc) in PEDOT:PSS paves the way to wide applications in device structural perspective, as to say, in n–i–p structure. The presence of the ester group in PVAc donates the bonding site to the perovskite layer, which improves the adhesion, resulting in enhanced charge transport ability as well as device stability. PVAc‐treated PEDOT:PSS device exhibited 20% higher power conversion efficiency (PCE) than the PVAc‐free device and retained 80% of initial PCE after 1000 h under extreme conditions (AM 1.5G and 60 °C).

Microbiological, thermal and mechanical performance of cellulose acetate films with geranyl acetate

The present work concerns to investigate the microbiological, thermal and mechanical behavior of cellulose acetate films obtained with addition of 0.5 % (v/v) and 1.0 % (v/v) of geranyl acetate by the casting technique. The antimicrobial activities of the polymeric films were assessed against Staphylococcus aureus and Escherichia coli bacteria and against Aspergillus flavus fungal. The achieved results show that the films presented antibacterial and antifungal activities. Moreover, the incorporation of the geranyl acetate in the polymeric films was confirmed by FTIR and TGA technique, while DSC analysis pointed out the compatibility between the geranyl acetate and cellulose acetate. The addition of the geranyl acetate did not modify the mechanical behavior of the cellulose acetate films concerning stiffness and tensile strength. These results suggest that this new material is promising for future applications in biomedical devices and food packaging.

Overexpression of UCP3 decreases mitochondrial efficiency in mouse skeletal muscle in vivo.

Uncoupling protein-3 (UCP3) is a mitochondrial transmembrane protein highly expressed in the muscle that has been implicated in regulating the efficiency of mitochondrial oxidative phosphorylation. Increasing UCP3 expression in skeletal muscle enhances proton leak across the inner mitochondrial membrane and increases oxygen consumption in isolated mitochondria, but its precise function in vivo has yet to be fully elucidated. To examine whether muscle-specific overexpression of UCP3 modulates muscle mitochondrial oxidation in vivo, rates of ATP synthesis were assessed by 31 P magnetic resonance spectroscopy (MRS), and rates of mitochondrial oxidative metabolism were measured by assessing the rate of [2-13 C]acetate incorporation into muscle [4-13 C]-, [3-13 C]-glutamate, and [4-13 C]-glutamine by high-resolution 13 C/1 H MRS. Using this approach, we found that the overexpression of UCP3 in skeletal muscle was accompanied by increased muscle mitochondrial inefficiency in vivo as reflected by a 42% reduction in the ratio of ATP synthesis to mitochondrial oxidation.

Incorporation of zero-valent silver and polyvinyl acetate on the surface matrix of carbon nanotubes for the adsorption of mercury and chromium from industrial wastewater

Herein, zero-valent silver (Ag0) and polyvinyl acetate (PVAc) was ultrasonically incorporated into the surface matrix of MWCNTs to produce a multifunctional MWCNTs-Ag0/PVAc nanocomposite. The MWCNTs, MWCNTs-Ag0 and MWCNTs-Ag0/PVAc were characterized for the thermal stability, crystallographic structure and morphology using thermogravimetric analysis (TGA), X-ray diffraction (XRD) and high resolution scanning electron microscopy (HRSEM). Industrial wastewater containing Hg(II) and Cr(VI) ions were treated using the fabricated MWCNTs-Ag0/PVAc at different adsorption parameters such as pH, adsorbent mass, adsorption time and temperature. The characterization result obtained indicated successful incorporation of the Ag0 and PVAc to the surface matrix of MWCNTs-Ag0/PVAc. The materials were thermally stable and the crystalline peaks/patterns of the incorporated materials were evident on the MWCNTs-Ag0/PVAc. The adsorption study revealed maximum adsorption capacity of 249 mg/g and 237 mg/g for the Hg(II) and Cr(VI) by MWCNTs-Ag0/PVAc at the pH (6 for Hg(II) and 3 for Cr(VI)), adsorbent mass (40 mg), adsorption time (60 min) and temperature (30 °C). The experimental data effectively fitted the Langmuir isotherm and pseudo-second order kinetic, respectively. Finally, MWCNTs-Ag0/PVAc showed remarkable performance as a suitable adsorbent for heavy metals removal from industrial wastewater.

Antimicrobial cellulose acetate films by incorporation of geranyl acetate for active food packaging application

The development of new antimicrobial polymeric materials is in prominence due to its versatility of applications, especially for the manufacture of active packaging food. Cellulose acetate is an example of polymeric material used to this purpose, due to its characteristics of biodegradability and easy processing, in addition its natural origin and no toxicity. Geranyl acetate is an ester derived from geraniol, which has good antimicrobial properties and good thermal stability, which makes it interesting to be applied as an antimicrobial agent, avoiding the trivial and often problematic metallic nanoparticles and also volatile essential oils. In this work, antibacterial and antifungal cellulose acetate films were obtained through the incorporation of geranyl acetate ester (in concentrations of 0.5 and 1.0% v/v), by using the casting technique. This new material was tested against gram-positive and gram-negative bacteria and fungi. Results showed that it is possible to obtain antibacterial and antifungal cellulose acetate films with the incorporation of geranyl acetate ester, with excellent antibacterial activity against gram-positive and gram-negative bacteria and good antifungal activity.

Investigation into the reaction of reactive dyes with carboxylate salts and the application of carboxylate‐modified reactive dyes to cotton

AbstractInk‐jet printing of cellulosic fabrics with reactive dyes typically requires that the fabric is pretreated with alkali, prior to printing, to facilitate efficient fixation of the dye. In this paper we evaluate the use of sodium formate and other carboxylate salts as a neutral (pH 6.5) pretreatment process. The thickened, prepared‐for‐print pad liquor contained at least 50 gdm−3 of the selected carboxylate salt and was applied to the cotton fabrics by a pad‐dry procedure. The fabric was then ink‐jet printed with reactive dye inks, followed by standard steaming and washing‐off processes. The pH of the carboxylate salt pretreatment was 6.5 and the aqueous extracts from the print fabrics at the end of the steaming process remained at pH 6.5. It was observed that even at pH 6.5, in the presence of selected carboxylates, significant reactive dye fixation could be achieved on a cotton substrate, whereas in the absence of the carboxylate, very little or even zero fixation was achieved. Infrared and capillary electrophoresis analyses of model reactions of reactive dyes with the carboxylate salts indicated that reactive ester residues were formed, and which subsequently promoted reaction with the cellulosic substrates. In addition to improving reactive dye fixation in ink‐jet printing, the carboxylate‐modified dyes were also demonstrated to improve long‐liquor dyeing properties on cotton substrates. As an extension of this carboxylate‐based printing process, the incorporation of lithium acetate (100 gdm−3) into the ink formulation was further studied and it was demonstrated that the necessity for a preparative pretreatment process could be eliminated.

Evidence for functional G-coupled protein receptors 43 and 120 in subcutaneous and intramuscular adipose tissue of Angus crossbred steers.

We conducted 3 independent experiments to demonstrate functional G-coupled protein receptor 43 (GPR43) and GPR120 in bovine intramuscular (i.m.) and subcutaneous (s.c.) adipose tissues. We hypothesized that media volatile fatty acids and long-chain fatty acids would affect cAMP-activated protein kinase-alpha (AMPKα) protein expression and cAMP concentrations differently in i.m. and s.c. adipose tissue. Experiment 1: oleic acid (18:1n-9) decreased phosphorylated AMPKα protein (p-AMPKα) and the p-AMPKα/AMPKα protein ratio in i.m. preadipocytes, increased the p-AMPKα/AMPKα protein ratio in bovine satellite cells, and had no effect in s.c. preadipocytes. Experment 2: ex vivo explants from the 5th to 8th longissimus thoracic rib muscle section of Angus crossbred steers were cultured 48 hr in media containing 0.25 µM ciglitizone, 5 mM glucose, and 5 mM acetate, in the absence or the presence of 100 µM oleic acid. Oleic acid increased acetate incorporation into fatty acids and GPR43 gene expression in i.m. adipose tissue (P < 0.05), but oleic acid had no effect on fatty acid synthesis or GPR43 expression in s.c. adipose tissue. Experiment 3: fresh s.c. and i.m. adipose tissue from the 5th to 8th longissimus thoracic rib muscle section of Angus crossbred steers was transferred immediately to 6-well culture plates containing 3 mL of KHB/Hepes/5 mM glucose. Samples were preincubated with 0.5 mM theophylline plus 10 μM forskolin for 30 min, after which increasing concentrations of acetate or propionate (0, 10-3, 10-2.3, and 10-3 M) in the absence or the presence of 100 μM oleic acid or 100 µM palmitic acid (16:0) were added to the incubation media. Acetate had no effect on forskolin-stimulated cAMP production in s.c. adipose tissue but decreased cAMP in i.m. adipose tissue (P < 0.05); this indicates a functional GPR43 receptor in i.m. adipose tissue. The combination of 10-2 M acetate and oleic acid decrease cAMP production in s.c. adipose tissue, consistent with GPR120 receptor activity, but oleic acid and palmitic acid attenuated the depression of cAMP production caused by acetate in i.m. adipose tissue. Palmitic acid depressed cAMP production in s.c. adipose tissue, and increased cAMP production in i.m. adipose tissue (P < 0.05). Propionate had no effect on cAMP production in s.c. or i.m. adipose tissue. These results provide evidence for functional GPR43 receptors in i.m. adipose tissue and GPR120 receptors in s.c. adipose tissue, both of which would suppress lipolysis.

Antimicrobial properties of chitosan and galactomannan composite coatings and physical properties of films made thereof

The aim of this study was to produce antimicrobial coatings and films based on the mixture of chitosan and galactomannan from Adenanthera pavonina L., with the incorporation of sodium acetate. The antimicrobial activity of the coatings was evaluated against L. monocytogenes, S. aureus, P. aeruginosa and S. enteritidis. Then the films produced, based on the coating formulations, were characterized in terms of water vapour permeability (WVP), oxygen (O2) and carbon dioxide (CO2) permeability, moisture content (MC), water solubility (S), tensile strength (TS), elongation at break (EB), elastic modulus (EM), opacity and color. The composite coatings with Chi were effective against Gram-negative and Gram-positive bacteria. Films Chi presented the low water solubility and high values of component b*, which indicates the predominance of yellowish coloration and the highest TS values. Films of Chi-Gal-NaA present lower values of S, MC, WVP and EB and is the film presenting the higher value of EM. While for the films of Gal-NaA there was a reduction of the O2 permeability and an increase of CO2 permeability. Chi in combination with NaA can be used in the development of antimicrobial coatings and films for food applications, therefore contributing to food preservation and shelf-life extension.

Eficácia e segurança do acetato de abiraterona para o tratamento de pacientes com câncer de próstata metastático resistente à castração e refratários à quimioterapia

Tecnologia: O acetato de abiraterona, medicamento apresentado na forma de comprimido, é um inibidor potente e irreversível da enzima que estimula a síntese de hormônios masculinos (andrógenos), os quais são responsáveis pelo crescimento e evolução do câncer de próstata. Indicação: O acetato de abiraterona é indicado para o tratamento de pacientes com câncer de próstata metastático resistente à castração. Pergunta: O acetato de abiraterona é eficaz e seguro para o tratamento de pacientes com câncer de próstata metastático resistente à castração e refratários à quimioterapia? Métodos: Para responder à pergunta PICO, as estratégias estruturadas de busca foram utilizadas nas seguintes bases de dados: Medline (via Pubmed), Cochrane Library, NICE EvidenceSearche Epistemonikos. Resultados: Foram identificadas 40 publicações, sendo que, após a avaliação dos textos recuperados, um artigo de revisão sistemática foi incluído nesta nota técnica. Conclusão: O acetato de abiraterona mostrou-se eficaz e seguro para o tratamento de pacientes com quadro de adenocarcinoma de próstata metastático resistente à castração e refratários à quimioterapia. Os dados científicos disponíveis demonstraram que o medicamento em questão relacionou-se à menor incidência de novas lesões tumorais, melhora da qualidade de vida, aumento da sobrevida global sem aumentar de maneira significativa a taxa de eventos adversos em comparação com o tratamento placebo. A evidência científica analisada de alta qualidade metodológica suporta a incorporação do acetato de abiraterona na lista de medicamentos padronizados da instituição.