MODELING OF EXTRUSION PROCESS USING RESPONSE SURFACE METHODOLOGY AND ARTIFICIAL NEURAL NETWORKS

Artificial neural networks are a powerful tool for modeling of extrusion processing of food materials. Wheat flour and wheat– black soybean blend (95:5) were extruded in a single screw Brabender extruder with varying temperature (120 and 140 oC), dry basis moisture content (18 and 20%) and screw speed (156, 168, 180, 192 and 204 rpm). The specific mechanical energy, water absorption index, water solubility index, expansion ratio and sensory characteristics (crispness, hardness, appearance and overall acceptability) were measured. Well expanded products could be obtained from wheat flour as well as the blend of wheat– black soybean. The results showed that artificial neural network (ANN) models performed better than the response surface methodology (RSM) models in describing the extrusion process and characteristics of the extruded product in terms of specific mechanical energy requirement, expansion ratio, water absorption index, water solubility index as well the sensory characteristics. The ANN models were better than RSM models both in case of the individual as well as the pooled data of wheat flour and wheat- black soybean extrusion

Characterisation of fibroblast-like synoviocytes from a murine model of joint inflammation

INTRODUCTION: Fibroblast-like synoviocytes (FLS) play a central role in defining the stromal environment in inflammatory joint diseases. Despite a growing use of FLS isolated from murine inflammatory models, a detailed characterisation of these cells has not been performed. METHODS: In this study, FLS were isolated from inflamed joints of mice expressing both the T cell receptor transgene KRN and the MHC class II molecule Ag7 (K/BxN mice) and their purity in culture determined by immunofluorescence and real-time reverse transcription polymerase chain reaction (real-time RT-PCR). Basal expression of proinflammatory genes was determined by real-time RT-PCR. Secreted interleukin 6 (IL-6) was measured by enzyme-linked immunosorbent assay (ELISA), and its regulation by tumor necrosis factor-alpha (TNF-α and corticosterone (the major glucocorticoid in rodents) measured relative to other mesenchymal cell populations. RESULTS: Purity of FLS culture was identified by positive expression of fibronectin, prolyl 4-hydroxylase, cluster of differentiation 90.2 (CD90.2) and 248 (CD248) in greater than 98% of the population. Cultured FLS were able to migrate and invade through matrigel, a process enhanced in the presence of TNF-α. FLS isolated from K/BxN mice possessed significantly greater basal expression of the inflammatory markers IL-6, chemokine ligand 2 (CCL-2) and vascular cell adhesion molecule 1 (VCAM-1) when compared to FLS isolated from non-inflamed tissue (IL-6, 3.6 fold; CCL-2, 11.2 fold; VCAM-1, 9 fold; P < 0.05). This elevated expression was abrogated in the presence of corticosterone at 100 nmol/l. TNF-α significantly increased expression of all inflammatory markers to a much greater degree in K/BxN FLS relative to other mesenchymal cell lines (K/BxN; IL-6, 40.8 fold; CCL-2, 1343.2 fold; VCAM-1, 17.8 fold; ICAM-1, 13.8 fold; P < 0.05), with secreted IL-6 mirroring these results (K/BxN; con, 169 ± 29.7 versus TNF-α, 923 ± 378.8 pg/ml/1 × 10(5 )cells; P < 0.05). Dose response experiments confirmed effective concentrations between 10 and 100 nmol/l for corticosterone and 1 and 10 ng/ml for TNF-α, whilst inflammatory gene expression in FLS was shown to be stable between passages four and seven. CONCLUSIONS: This study has established a well characterised set of key inflammatory genes for in vitro FLS culture, isolated from K/BxN mice and non-inflamed wild-type controls. Their response to both pro- and anti-inflammatory signalling has been assessed and shown to strongly resemble that which is seen in human FLS culture. Additionally, this study provides guidelines for the effective characterisation, duration and treatment of murine FLS culture

The Role of Glucocorticoid Receptor in Mature Osteoblasts and Osteocytes in Bone Modelling and Bone Remodelling

Endogenous glucocorticoids (GCs) are known for their role in maintaining glucose homeostasis. GCs are also essential for several biological functions including metabolic, immunologic and cardiovascular functions. Previous research have shown that the targeted overexpression of 11β-HSD type 2 enzyme resulting in the abrogation of endogenous GC signalling in osteoblasts at the pre-receptor level, is associated with impaired bone acquisition in mice. This study examined the skeletal phenotype of mice with glucocorticoid receptor (GR) deletion in mature osteoblasts and osteocytes, during bone remodelling and modelling. Mature osteoblast and osteocyte specific GR knock-out mice (obGRKO) were generated by crossing GRflox/flox mice with a transgenic mouse line expressing cre recombinase under the control of a type I collagen (Col2.3) truncated rat promoter. At 12-weeks (bone remodelling) and 3-weeks (bone modelling) of age, vertebrae and tibiae from male and female obGRKO mice and their Cre-negative GRflox/flox wildtype (WT) littermates were harvested and examined to observe the effects of the knockout gene. In bone remodelling there was a significant decrease in vertebral bone volume across both male and female obGRKO mice, compared to WT. This was largely due to a reduction in trabecular number, and a corresponding increase in trabecular separation in obGRKO mice. Interestingly, the trabecular bone parameters in the tibia were similar between obGRKO and WT mice, during bone remodelling. Results also revealed that the low vertebral bone mass in obGRKO mice was associated with a significant increase in osteoclast number and surface when compared with WT. In addition, no differences was observed in molecular or bone turnover markers between obGRKO and WT. However, the deletion of GR in osteoblasts/osteocytes during bone modelling demonstrated no apparent effect on the skeleton in postnatal mice. These results indicate that endogenous GC signalling in osteoblasts via the GR pathway is crucial for the accrual and maintenance of vertebral trabecular bone mass, during bone remodelling. Furthermore, GC signalling may have a role in osteoblast-mediated bone resorption specifically in vertebral trabecular bone

Deletion of Mesenchymal Glucocorticoid Receptor Attenuates Embryonic Lung Development and Abdominal Wall Closure

<div><p>As a member of the nuclear hormone receptor superfamily of ligand-activated transcription factors, the glucocorticoid receptor (GR) is essential for normal embryonic development. To date, the role of mesenchymal glucocorticoid signaling during development has not been fully elucidated. In the present study, we investigated the role of the GR during embryogenesis specifically in mesenchymal tissues. To this aim, we crossed GRflox mice with Dermo1-Cre mice to generate GR^Dermo1 mice, where the GR gene was deleted within mesenchymal cells. Compared to their wild type littermates, GR^Dermo1 mice displayed severe pulmonary atelectasis, defects in abdominal wall formation resulting in intestinal herniation, abnormal extracellular matrix synthesis in connective tissues and high postnatal lethality. Lungs of GR^Dermo1 mice failed to progress from the canalicular to saccular stage, as evidenced by the presence of immature air sacs, thickened interstitial mesenchyme and an underdeveloped vascular network between E17.5 and E18.5. Furthermore, myofibroblasts and vascular smooth muscle cells, although present in normal numbers in GR^Dermo1 animals, were characterized by significantly reduced elastin synthesis, whilst epithelial lining cells of the immature saccules were poorly differentiated. A marked reduction in normal elastin and collagen deposits were also observed in connective tissues adjacent to the umbilical hernia. This study demonstrates that eliminating the GR in cells of the mesenchymal lineage results in marked effects on interstitial fibroblast function, including a significant decrease in elastin synthesis. This results in lung atelectasis and postnatal lethality, as well as additional and hitherto unrecognized developmental defects in abdominal wall formation. In addition, altered glucocorticoid signaling in the mesenchyme attenuates normal lung epithelial differentiation.</p></div

Are In Vitro Human Blood–Brain–Tumor-Barriers Suitable Replacements for In Vivo Models of Brain Permeability for Novel Therapeutics?

Background: High grade gliomas (HGG) are incapacitating and prematurely fatal diseases. To overcome the poor prognosis, novel therapies must overcome the selective and restricted permeability of the blood–brain barrier (BBB). This study critically evaluated whether in vitro human normal BBB and tumor BBB (BBTB) are suitable alternatives to “gold standard” in vivo models to determine brain permeability. Methods: A systematic review utilizing the PRISMA guidelines used English and full-text articles from the past 5 years in the PubMed, Embase, Medline and Scopus databases. Experimental studies employing human cell lines were included. Results: Of 1335 articles, the search identified 24 articles for evaluation after duplicates were removed. Eight in vitro and five in vivo models were identified with the advantages and disadvantages compared within and between models, and against patient clinical data where available. The greatest in vitro barrier integrity and stability, comparable to in vivo and clinical permeability data, were achieved in the presence of all cell types of the neurovascular unit: endothelial cells, astrocytes/glioma cells, pericytes and neurons. Conclusions: In vitro co-culture BBB models utilizing stem cell-derived or primary cells are a suitable proxy for brain permeability studies in order to reduce animal use in medical research