Novel postharvest processing strategies for value-added applications of marine algae.

Marine algae are regarded as a promising nutrients resource in future as they can be sustainably cultured without land and high investment. These macroalgae are now widely processed into food and beverages, fertilizers and animal feed. Furthermore, bioactive compounds such as polysaccharides and polyphenols in seaweeds have proven to have antibacterial, antiviral and antifungal properties that can be utilized in cosmeceuticals, nutraceuticals and pharmaceuticals. As a key procedure in seaweed production, the postharvest process not only requires more laboured and energy but also affect the quality of the final product significantly. This article reviewed all current postharvest processes and technologies of seaweed and addressed potential postharvest strategies for seaweed production. © 2021 Society of Chemical Industry.

Increased vascular endothelial growth factor mRNA in endomyocardial biopsies from allografts demonstrating severe acute rejection: a longitudinal study.

Investigation into the contribution of the immune system and inflammatory cascade to acute rejection (AR) and cardiac allograft vasculopathy (CAV) has implicated vascular endothelial growth factor (VEGF). The endomyocardial biopsy (EB) has proved invaluable in the diagnosis of AR, and in providing information concerning the biological processes occurring following transplantation. The association between VEGF and AR and the development of CAV was examined in endomyocardial biopsies (EBs) from a cohort of 76 heart transplant recipients. VEGF mRNA levels were quantified through real time RT-PCR in 712 EBs, obtained at routine intervals during post-operative monitoring. VEGF and leukocyte and endothelial markers were assessed in a subset of biopsies through immunohistochemistry. The results of generalised linear modelling, adjusting for covariates, revealed VEGF mRNA expression was 19% greater during severe AR as compared to no rejection (p=0.007). Immunohistochemical results supported these findings. Mean VEGF mRNA levels were not significant predictors for the development of CAV (p=0.554). However the risk of cardiac related death increased 9-fold for a 1 unit increase in mean VEGF expression (p=0.006). Similarly, a single unit increase in mean AR severity equated to a 10-fold increase in the risk of cardiac related death (p<0.005). Our data suggest that increased VEGF expression is strongly associated with severe AR and cardiac related death.

Fas-induced apoptosis is a feature of progressive diabetic nephropathy in transgenic (mRen-2)27 rats: attenuation with renin-angiotensin blockade.

BACKGROUND AND AIM: Tubular atrophy is a major feature of most renal diseases and is closely associated with the loss of renal function. The present study sought to investigate whether Fas/FasL-induced tubular epithelial cell apoptosis was a feature of experimental diabetic nephropathy. The effects of renoprotective therapy with blockade of the renin-angiotensin (RAS) system were also examined. METHOD: Six-week-old female Ren-2 rats were injected with streptozotocin and maintained diabetic for 12 weeks. Further groups of diabetic rats were treated with the angiotensin-converting enzyme inhibitor, perindopril, for 12 weeks. RESULTS: Widespread apoptosis, identified by using mediated Terminal dUTP nick-end labelling (TUNEL) staining was noted in the tubules of diabetic Ren-2 rats. These changes were associated with an increase in both Fas mRNA and Fas L (ligand) within the tubules (P < 0.01). Treatment of diabetic Ren-2 rats with perindopril (6 mg/kg per day) reduced the apoptosis to control levels and was associated with a reduction in Fas mRNA and Fas L protein (P < 0.05). CONCLUSION: In conclusion, Fas/Fas L-induced tubular apoptosis is a feature of diabetic Ren-2 rats and is attenuated by the blockade of the RAS.

Over-expression of platelet-derived growth factor in human diabetic nephropathy.

BACKGROUND: The pathogenetic mechanisms responsible for progressive renal impairment of diabetic nephropathy are still poorly understood, despite its growing incidence. Increasing evidence suggests that growth factors may contribute to the initiation and progressive fibrosis of diabetic nephropathy. In this study, the gene expression and protein distribution of platelet-derived growth factor-A and -B (PDGF-A and PDGF-B) in human diabetic nephropathy were examined. METHODS: PDGF-A and PDGF-B mRNA levels in surplus renal biopsy tissue from seven patients with overt diabetic nephropathy and six nephrectomy samples were examined using quantitative reverse transcription-polymerase chain reaction (RT-PCR). In addition, each sample was also examined immunohistochemically to quantify and localize peptide expression of each PDGF isoform. RESULTS: Gene expression of PDGF-A and PDGF-B mRNA were increased 22- and 6-fold, respectively, in biopsies from patients with diabetic nephropathy compared with control tissue. Immunostaining also demonstrated increased peptide expression of both PDGF-A and PDGF-B in diabetic nephropathy, with each isoform showing a specific pattern of tissue distribution. CONCLUSIONS: The findings of increased gene and protein expression of PDGF in renal biopsies from patients with diabetic nephropathy imply a potential role for this prosclerotic growth factor in the development of the progressive fibrosis that characterizes human diabetic kidney disease.