Model Karakteristik Self Excited Vibrations Aliran Fluida Akibat Perubahan Konstanta Elastis Tube

Analisis eksperimental pada penelitian ini dilakukan untuk memperoleh karakteristik self excited vibrations secara aktual. Karakteristik self excited vibrations hanya dapat diamati pada kondisi kritis yang mempunyai nilai pinch ratio tertentu. Pengambilan data dengan alat ukur getaran (vibrations meter) untuk mengukur karakteristik getaran yang terjadi berupa frekwensi, amplitudo dan analisis FFT (Fast Fourier Transform). Perubahan konstanta elastis selang menghasilkan frekwensi getaran pada rentang 5,83 Hz – 10,00 Hz. Sedangkan amplitudo getaran yang dihasilkan menurun dengan berkurangnya kecepatan aliran yaitu pada rentang 0,30 mm – 1,95 mm. Pengaruh Perubahan konstanta elastis selang juga dapat dinyatakan dengan parameter indeks kecepatan (S). Indeks kecepatan yang dihasilkan pada selang dengan konstanta K3 menghasilkan rentang S3 = 2,61 – 3,37, K2 menghasilkan rentang S2 = 2,69 – 3,51, dan K1 menghasilkan rentang S1 = 2,82 – 3,71. Selain itu penurunan pinch ratio (be) menyebabkan indeks kecepatannya juga menurun karena kekakuan sistem akan meningkat akibat meningkatnya tekanan fluida. Parameter lain yang menunjukkan pengaruh konstanta elastis selang adalah bilangan Womersley (α) dan angka Strouhal (St). Pada selang dengan konstanta K3 menghasilkan rentang angka Strouhal St3 = 0,30 – 0,38, K2 menghasilkan St2 = 0,29 – 0,37, dan K1 menghasilkan St1 = 0,27 – 0,35. Selain itu pada selang dengan konstanta K3 menghasilkan rentang α3 = 65,35 – 68,38, K2 menghasilkan α2 = 64,07 – 67,24, dan K1 menghasilkan α1 = 62,26 – 65,69. Kesimpulan yang diperoleh dari penelitian ini adalah parameter bilangan Womersley (α) dan angka Strouhal (St) meningkat dengan bertambahnya konstanta elastis selang dan kekakuan sistem. Sedangkan indeks kecepatan (S) menurun dengan meningkatnya konstanta elastis selang

Adipose Tissue: Understanding the Heterogeneity of Stem Cells for Regenerative Medicine

Adipose-derived stem cells (ASCs) have been increasingly used as a versatile source of mesenchymal stem cells (MSCs) for diverse clinical investigations. However, their applications often become complicated due to heterogeneity arising from various factors. Cellular heterogeneity can occur due to: (i) nomenclature and criteria for definition; (ii) adipose tissue depots (e.g., subcutaneous fat, visceral fat) from which ASCs are isolated; (iii) donor and inter-subject variation (age, body mass index, gender, and disease state); (iv) species difference; and (v) study design (in vivo versus in vitro) and tools used (e.g., antibody isolation and culture conditions). There are also actual differences in resident cell types that exhibit ASC/MSC characteristics. Multilineage-differentiating stress-enduring (Muse) cells and dedifferentiated fat (DFAT) cells have been reported as an alternative or derivative source of ASCs for application in regenerative medicine. In this review, we discuss these factors that contribute to the heterogeneity of human ASCs in detail, and what should be taken into consideration for overcoming challenges associated with such heterogeneity in the clinical use of ASCs. Attempts to understand, define, and standardize cellular heterogeneity are important in supporting therapeutic strategies and regulatory considerations for the use of ASCs

Retinoic acid is abundantly detected in different depots of adipose tissue by sers

Retinoic acid (RA) is essential for early developmental processes and stem cell differentiation, but less is known about its contributions to adult tissues and stem cells including adipose tissue. We previously demonstrated that many genes involved in RA synthesis and downstream pathway are differentially expressed in adipose-derived stem cells (ASCs) from visceral fat compared to those from subcutaneous fat, leading to changes in their early adipogenic functions. In order to study potential contributions of RA in adipose tissue, we measured tissue RA levels using a technique based on surface-enhanced Raman spectroscopy (SERS). The data indicate heretofore underappreciated abundance of endogenous RA in mouse adipose tissue compared to other tissues and dynamic changes of RA concentrations after high fat diet feeding. Our results lay the foundation for further investigation on the functional role of RA in adipose tissue development and metabolism

Retinoic acid is abundantly detected in different depots of adipose tissue by sers

Retinoic acid (RA) is essential for early developmental processes and stem cell differentiation, but less is known about its contributions to adult tissues and stem cells including adipose tissue. We previously demonstrated that many genes involved in RA synthesis and downstream pathway are differentially expressed in adipose-derived stem cells (ASCs) from visceral fat compared to those from subcutaneous fat, leading to changes in their early adipogenic functions. In order to study potential contributions of RA in adipose tissue, we measured tissue RA levels using a technique based on surface-enhanced Raman spectroscopy (SERS). The data indicate heretofore underappreciated abundance of endogenous RA in mouse adipose tissue compared to other tissues and dynamic changes of RA concentrations after high fat diet feeding. Our results lay the foundation for further investigation on the functional role of RA in adipose tissue development and metabolism

Retinoic acid is abundantly detected in different depots of adipose tissue by sers

Retinoic acid (RA) is essential for early developmental processes and stem cell differentiation, but less is known about its contributions to adult tissues and stem cells including adipose tissue. We previously demonstrated that many genes involved in RA synthesis and downstream pathway are differentially expressed in adipose-derived stem cells (ASCs) from visceral fat compared to those from subcutaneous fat, leading to changes in their early adipogenic functions. In order to study potential contributions of RA in adipose tissue, we measured tissue RA levels using a technique based on surface-enhanced Raman spectroscopy (SERS). The data indicate heretofore underappreciated abundance of endogenous RA in mouse adipose tissue compared to other tissues and dynamic changes of RA concentrations after high fat diet feeding. Our results lay the foundation for further investigation on the functional role of RA in adipose tissue development and metabolism

Trxlp, a thioredoxin-like effector from Edwardsiella piscicida inhibits cellular redox signaling and nuclear translocation of NF-kappa B

10.1016/j.ijbiomac.2020.01.114INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES14889-10

Suppression of adipogenesis by pathogenic seipin mutant is associated with inflammatory response.

BACKGROUND: While pathogenic mutations in BSCL2/Seipin cause congenital generalized lipodystrophy, the underlying mechanism is largely unknown. In this study, we investigated whether and how the pathogenic missense A212P mutation of Seipin (Seipin-A212P) inhibits adipogenesis. METHODOLOGY/RESULTS: We analyzed gene expression and lipid accumulation in stable 3T3-L1 cell lines expressing wild type (3T3-WT), non-lipodystrophic mutants N88S (3T3-N88S) and S90L (3T3-S90L), or lipodystrophic mutant A212P Seipin (3T3-A212P). When treated with adipogenic cocktail, 3T3-WT, 3T3-N88S and 3T3-S90L cells exhibited proper differentiation into mature adipocytes, indistinguishable from control 3T3-L1 cells. In contrast, adipogenesis was significantly impaired in 3T3-A212P cells. The defective adipogenesis in 3T3-A212P cells could be partially rescued by either PPARγ agonist or PPARγ overexpression. Gene expression profiling by microarray revealed that inhibition of adipogenesis was associated with activation of inflammatory genes including IL-6 and iNOS. We further demonstrated that Seipin-A212P expression at pre-differentiation stages significantly activated inflammatory responses by using an inducible expression system. The inflammation-associated inhibition of adipogenesis could be rescued by treatment with anti-inflammatory agents. CONCLUSIONS: These results suggest that pathogenic Seipin-A212P inhibits adipogenesis and the inhibition is associated with activation of inflammatory pathways at pre-differentiation stages. Use of anti-inflammatory drugs may be a potential strategy for the treatment of lipodystrophy

Diffuse optical spectroscopy and imaging to detect and quantify adipose tissue browning

Adipose (fat) tissue is a complex metabolic organ that is highly active and essential. In contrast to white adipose tissue (WAT), brown adipose tissue (BAT) is deemed metabolically beneficial because of its ability to burn calories through heat production. The conversion of WAT-resident adipocytes to "beige" or "brown-like" adipocytes has recently attracted attention. However, it typically takes a few days to analyze and confirm this browning of WAT through conventional molecular, biochemical, or histological methods. Moreover, accurate quantification of the overall browning process is not possible by any of these methods. In this context, we report the novel application of diffuse reflectance spectroscopy (DRS) and multispectral imaging (MSI) to detect and quantify the browning process in mice. We successfully demonstrated the time-dependent increase in browning of WAT, following its induction through beta-adrenergic agonist injections. The results from these optical techniques were confirmed with those of standard molecular and biochemical assays, which measure gene and protein expression levels of UCP1 and PGC-1 alpha, as well as with histological examinations. We envision that the reported optical methods can be developed into a fast, real time, cost effective and easy to implement imaging approach for quantification of the browning process in adipose tissue

Comparative Study of Adipose-Derived Stem Cells From Abdomen and Breast

Background: Abdominal tissue enriched with adipose-derived stem cells (ASCs) is often used in cell-assisted lipotransfer procedures for breast reconstruction. However, as the tissue microenvironment and stem cell niche play important roles in defining the characteristics of the resident cells, it is hypothesized that the stem cell population present in the donor abdominal tissue has dissimilar properties as compared with the cells in the recipient breast tissue, which may ultimately affect the long-term success of the graft. Methods: Adipose-derived stem cells were isolated from breast and abdominal fat tissues and characterized for mesenchymal-specific cell surface markers, and their population doubling, colony-forming capabilities, and proliferative properties were compared. The multilineage potential of both cell populations was also investigated. Results: Adipose-derived stem cells from both tissue sites were found to possess similar marker expression and multilineage differentiation potential. However, breast fat–derived ASCs were observed to have a higher self-renewal capability and an unstable population doubling as compared with abdominal fat-derived ASCs. Gene expression studies revealed that the breast fat–derived ASCs were predisposed to the osteogenic lineage and the abdominal fat–derived ASCs to the adipogenic lineage. Conclusions: Cells derived from both fat tissues possess different characteristics in terms of their growth kinetics and predisposition to the osteolineages and adipolineages. In particular, ASCs from the abdominal tissue appear to contribute to adipose tissue turnover, whereas ASCs from breast tissue, if used for cell-assisted fat grafting, may potentially be responsible for complications in fat grafting, such as oil cysts, calcifications, fat necrosis, and tumors.Accepted versio