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We have developed a hollow fiber bioreactor-based production system for manufacturing large quantities of extracellular vesicles (EVs) containing exosomes from adult human adipose-derived stromal/stem cells (ASCs). By manipulating the cellular bioreactor environment, we have found that we can alter ASC EV production, secretion, and surface protein composition. The aims of this chapter are to describe the methodology for culturing and tuning of adipose ASCs in a bioreactor, along with the collection and isolation of the EVs containing exosomes demonstrating increased HSP70 content., (© 2024. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

A home-made silica-based silver ion solid-phase extraction (Ag+-SPE) system for the fractionation and subsequent gas chromatographic analysis of trans fatty acids in human adipose tissue is developed and examined. Analytical characteristics of the home-made Ag+-SPE column were compared with those of the commercial Discovery Ag-Ion SPE column and it was demonstrated that the both columns can be applied for the fractionation of fatty acid methyl esters. [ABSTRACT FROM AUTHOR]

Silver ion solid-phase extraction is suggested for the analysis of trans fatty acids in human adipose. Acid catalyzed esterification of the fatty acids protocol using boron trifluoride-methanol complex as a catalyst was used. Silica based Ag+-SPE conditions are presented. A mixture of dichloromethane and hexane with the content of dichloromethane increasing from 5 to 100% was used as an eluent. The presented method allows eliminating from the trans chromatographic zone about 75% of cis isomers of fatty acid methyl esters, thus enabling to determine trace contents of trans fatty acids in the samples containing big amounts of dominant saturated, monounsaturated and polyunsaturated fatty acids. [ABSTRACT FROM AUTHOR]

Designing degradable hydrogels is complicated by the structural and temporal complexities of the gel and evolving tissue. A major challenge is to create scaffolds with sufficient mechanical properties to restore initial function while simultaneously controlling temporal changes in the gel structure to facilitate tissue formation. Poly(ethylene glycol) was used in this work, to form biodegradable poly(ethylene glycol)-based hydrogels with hydrolyzable poly-l-lactide segments in the backbone. Non-degradable poly(ethylene glycol) was also introduced in the formulation to obtain control of the degradation profile that encompasses cell growth and new tissue formation. The dependence on polymer composition was observed by higher degradation profiles and decreased mechanical properties as the content of degradable segments was increased in the formulation. Based on in vitro tests, no toxicity of extracts or biomaterial in direct contact with human adipose tissue stem cells was observed, and the ultraviolet light treatment did not affect the proliferation capacity of the cells. [ABSTRACT FROM AUTHOR]

Twenty five human breast adipose tissue samples were collected in Porto Alegre, Brazil during 2004–2005 and analyzed for polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs). ΣPBDE concentrations (sum of tri- to hepta-BDEs) ranged from 0.19 to 132 ng/g lipid with a median of 1.51 ng/g lipid. These concentrations are 3- to 100-times lower than those reported from other countries, with the exception of Japan, probably reflecting lower usage of PBDE-containing products or lower exposures to these chemicals. The predominant congener was BDE-47, followed by BDEs 99, 183, 153 and 100. One individual in the dataset had about 70-times higher PBDE concentrations than the rest of the participants. ΣPCB (sum of PCBs 118, 138, 153, 180) ranged from 30 to 339 ng/g lipid, with a median of 51 ng/g lipid. No age dependency was found for PBDEs (r =−0.800–0.374, p >0.05) or PCB 180 (r =0.278, p >0.05). On the other hand, PCBs 118, 138 and 153 did show age dependency (r =0.410–0.458, p <0.05). This is the first study to report levels of PBDEs in human breast adipose from Brazil. [Copyright &y& Elsevier]

Abstract: Polychlorinated biphenyls (PCBs) were monitored in Belgian human adipose tissue samples from deceased individuals (n=100). Their mean age was 52, ranging from 2 to 91 years. There were 57 men and 43 women. Other known variables were date of autopsy and place of residence. No information about diet or occupation was available. The seven marker congeners PCB 28, 52, 101, 118, 138, 153 and 180 were analysed in the samples with a GC–MS/MS method validated according to Commission Decision 2002/657/EC. Extracted fat was cleaned-up over a glass column filled with n-hexane, acid silica, deactivated alumina and anhydrous sodium sulfate. The whole procedure was subjected to a rigorous quality control programme with retention times, ion chromatograms and intensity ratios of the monitored product ions as identification criteria. The total PCB concentration ranged between 10 and 1640ngg−1 fat, with a mean value of 658ngg−1 fat. In the age groups of 0–9 (n=1), 10–19 (n=4), 20–29 (n=11), 30–39 (n=13), 40–49 (n=15), 50–59 (n=14), 60–69 (n=14), 70–79 (n=20), 80–89 (n=6) and 90–99 (n=2), the mean total PCB concentrations were 10, 134, 253, 445, 557, 687, 807, 962, 959, and 1191ngg−1 fat, respectively. So, there was an increase of PCB body burden with age. For the male subjects (n=57; mean age of 53) the mean total PCB concentration was 633ngg−1 fat. For the female subjects (n=43; mean age of 52) it was 690ngg−1 fat. There was no significant sex-related difference in the concentrations of marker PCBs. [Copyright &y& Elsevier]